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1

National Spherical Torus Experiment Upgrade Status and Plans*  

E-Print Network [OSTI]

fusion nuclear environment of copious neutrons to develop an experimental database on: ­ Nuclear is unique challenge for ST-based Fusion Nuclear Science Facility · NSTX-U goals: ­ Generate ~0.3-0.4MA fullNational Spherical Torus Experiment Upgrade ­ Status and Plans* J. Menard, PPPL For the NSTX-U Team

2

Implementation of BN Control in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

We have designed and constructed a system for control of the normalized B in the National Spherical Torus Experiment [M. Ono, et al., Nuclear Fusion 40, 557 (2000)]. A PID operator is applied to the difference between the present value of B N (from realtime equilibrium reconstruction) and a time-dependent request, in order to calculate the required injected power. This injected power request is then turned into modulations of the neutral beams. The details of this algorithm are described, including the techniques used to develop the appropriate control gains. Example uses of the system are shown

Gerhardt, S; Bell, M G; Cropper, M; Gates, D A; Koleman, E; Lawson, J; Marsala, B; Menard, J E; Mueller, D

2012-09-15T23:59:59.000Z

3

Divertor Heat Flux Mitigation in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

Steady-state handling of divertor heat flux is a critical issue for both ITER and spherical torus-based devices with compact high power density divertors. Significant reduction of heat flux to the divertor plate has been achieved simultaneously with favorable core and pedestal confinement and stability properties in a highly-shaped lower single null configuration in the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 2000] using high magnetic flux expansion at the divertor strike point and the radiative divertor technique. A partial detachment of the outer strike point was achieved with divertor deuterium injection leading to peak flux reduction from 4-6 MW m{sup -2} to 0.5-2 MW m{sup -2} in small-ELM 0.8-1.0 MA, 4-6 MW neutral beam injection-heated H-mode discharges. A self-consistent picture of outer strike point partial detachment was evident from divertor heat flux profiles and recombination, particle flux and neutral pressure measurements. Analytic scrape-off layer parallel transport models were used for interpretation of NSTX detachment experiments. The modeling showed that the observed peak heat flux reduction and detachment are possible with high radiated power and momentum loss fractions, achievable with divertor gas injection, and nearly impossible to achieve with main electron density, divertor neutral density or recombination increases alone.

Soukhanovskii, V A; Maingi, R; Gates, D A; Menard, J E; Paul, S F; Raman, R; Roquemore, A L; Bell, M G; Bell, R E; Boedo, J A; Bush, C E; Kaita, R; Kugel, H W; LeBlanc, B P; Mueller, D

2008-08-04T23:59:59.000Z

4

National Spherical Torus Experiment (NSTX) and Planned Research  

SciTech Connect (OSTI)

The U.S. fusion energy sciences program began in 1996 to increase emphasis on confinement concept innovation. The NSTX [1,2] is being built at PPPL as a national fusion science research facility in response to this emphasis. NSTX is to test fusion science principles of the Spherical Torus (ST) plasmas, which include: (1) High plasma pressure in low magnetic field for high fusion power density, (2) Good energy confinement is a small-size plasma, (3) Nearly fully self-driven (bootstrap) plasma current, (4) Dispersed heat and particle fluxes, and (5) Plasma startup without complicated inboard solenoid magnet. These properties of the ST plasma, if verified, would lead to possible future fusion devices of high fusion performance, small size, feasible power handling, and improved economy. The design of NSTX is depicted in Fig.1. The device is designed to study plasmas with major radius up to 85 cm, minor radius up to 68 cm, elongation up to 2, with flexibility in forming double-null, single-null, and inboard limited plasmas. The nominal operation calls for a toroidal field of 0.3 T for 5 s at the major radius, and a plasma current at 1 MA with q {approximately} 10 at edge. It features a compact center stack containing the inner legs of the toroidal field coils, a full size solenoid capable of delivering 0.6 Wb induction, inboard vacuum vessel, and composite carbon tiles. The center stack can be replaced without disturbing the main device, diagnostics, and auxiliary systems. The vessel will be covered fully with graphite tiles and can be baked to 350 C. Other wall conditioning techniques are also planned.

Kaye, S.; Neumeyer, C.; Ono, M.; Peng, M.

1999-11-13T23:59:59.000Z

5

Strike Point Control for the National Spherical Torus Experiment (NSTX)  

SciTech Connect (OSTI)

This paper presents the first control algorithm for the inner and outer strike point position for a Spherical Torus (ST) fusion experiment and the performance analysis of the controller. A liquid lithium divertor (LLD) will be installed on NSTX which is believed to provide better pumping than lithium coatings on carbon PFCs. The shape of the plasma dictates the pumping rate of the lithium by channeling the plasma to LLD, where strike point location is the most important shape parameter. Simulations show that the density reduction depends on the proximity of strike point to LLD. Experiments were performed to study the dynamics of the strike point, design a new controller to change the location of the strike point to desired location and stabilize it. The most effective PF coils in changing inner and outer strike points were identified using equilibrium code. The PF coil inputs were changed in a step fashion between various set points and the step response of the strike point position was obtained. From the analysis of the step responses, PID controllers for the strike points were obtained and the controller was tuned experimentally for better performance. The strike controller was extended to include the outer-strike point on the inner plate to accommodate the desired low outer-strike points for the experiment with the aim of achieving "snowflake" divertor configuration in NSTX.

Kolemen, E.; Gates, D. A.; Rowley, C. W.; Kasdin, N. J.; Kallman, J.; Gerhardt, S.; Soukhanovskii, V.; Mueller, D.

2010-07-09T23:59:59.000Z

6

Overview of Results from the National Spherical Torus Experiment (NSTX)  

SciTech Connect (OSTI)

The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high {beta} operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies confirm the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance l{sub i} {approx} 0.4 with strong shaping ({kappa} {approx} 2.7, {delta} {approx} 0.8) with {beta}{sub N} approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction f{sub NI} {approx} 71%. Instabilities driven by super-Alfvenic ions are an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvenic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. RWM/RFA feedback combined with n = 3 error field control was used on NSTX to maintain plasma rotation with {beta} above the no-wall limit. The impact of n > 1 error fields on stability is a important result for ITER. Other highlights are: results of lithium coating experiments, momentum confinement studies, scrape-off layer width scaling, demonstration of divertor heat load mitigation in strongly shaped plasmas, and coupling of CHI plasmas to OH ramp-up. These results advance the ST towards next step fusion energy devices such as NHTX and ST-CTF.

Gates, D; Ahn, J; Allain, J; Andre, R; Bastasz, R; Bell, M; Bell, R; Belova, E; Berkery, J; Betti, R; Bialek, J; Biewer, T; Bigelow, T; Bitter, M; Boedo, J; Bonoli, P; Bozzer, A; Brennan, D; Breslau, J; Brower, D; Bush, C; Canik, J; Caravelli, G; Carter, M; Caughman, J; Chang, C; Choe, W; Crocker, N; Darrow, D; Delgado-Aparicio, L; Diem, S; D'Ippolito, D; Domier, C; Dorland, W; Efthimion, P; Ejiri, A; Ershov, N; Evans, T; Feibush, E; Fenstermacher, M; Ferron, J; Finkenthal, M; Foley, J; Frazin, R; Fredrickson, E; Fu, G; Funaba, H; Gerhardt, S; Glasser, A; Gorelenkov, N; Grisham, L; Hahm, T; Harvey, R; Hassanein, A; Heidbrink, W; Hill, K; Hillesheim, J; Hillis, D; Hirooka, Y; Hosea, J; Hu, B; Humphreys, D; Idehara, T; Indireshkumar, K; Ishida, A; Jaeger, F; Jarboe, T; Jardin, S; Jaworski, M; Ji, H; Jung, H; Kaita, R; Kallman, J; Katsuro-Hopkins, O; Kawahata, K; Kawamori, E; Kaye, S; Kessel, C; Kim, J; Kimura, H; Kolemen, E; Krasheninnikov, S; Krstic, P; Ku, S; Kubota, S; Kugel, H; La Haye, R; Lao, L; LeBlanc, B; Lee, W; Lee, K; Leuer, J; Levinton, F; Liang, Y; Liu, D; Luhmann, N; Maingi, R; Majeski, R; Manickam, J; Mansfield, D; Maqueda, R; Mazzucato, E; McCune, D; McGeehan, B; McKee, G; Medley, S; Menard, J; Menon, M; Meyer, H; Mikkelsen, D; Miloshevsky, G; Mitarai, O; Mueller, D; Mueller, S; Munsat, T; Myra, J; Nagayama, Y; Nelson, B; Nguyen, X; Nishino, N; Nishiura, M; Nygren, R; Ono, M; Osborne, T; Pacella, D; Park, H; Park, J; Paul, S; Peebles, W; Penaflor, B; Peng, M; Phillips, C; Pigarov, A; Podesta, M; Preinhaelter, J; Ram, A; Raman, R; Rasmussen, D; Redd, A; Reimerdes, H; Rewoldt, G; Ross, P; Rowley, C; Ruskov, E; Russell, D; Ruzic, D; Ryan, P; Sabbagh, S; Schaffer, M; Schuster, E; Scott, S; Shaing, K; Sharpe, P; Shevchenko, V; Shinohara, K; Sizyuk, V; Skinner, C; Smirnov, A; Smith, D; Smith, S; Snyder, P; Soloman, W; Sontag, A; Soukhanovskii, V; Stoltzfus-Dueck, T; Stotler, D; Strait, T; Stratton, B; Stutman, D; Takahashi, R; Takase, Y; Tamura, N; Tang, X; Taylor, G; Taylor, C; Ticos, C; Tritz, K; Tsarouhas, D; Turrnbull, A; Tynan, G; Ulrickson, M; Umansky, M; Urban, J; Utergberg, E; Walker, M; Wampler, W; Wang, J; Wang, W; Weland, A

2009-01-05T23:59:59.000Z

7

National Spherical Torus Experiment (NSTX) | Princeton Plasma Physics Lab  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn Cyber Security Nuclear ForensicsScienceScience

8

Spherical torus fusion reactor  

DOE Patents [OSTI]

A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

Peng, Yueng-Kay M. (Oak Ridge, TN)

1989-01-01T23:59:59.000Z

9

Modification Of The Electron Energy Distribution Function During Lithium Experiments On The National Spherical Torus Experiment  

SciTech Connect (OSTI)

The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX.

Jaworski, M A; Gray, T K; Kaita, R; Kallman, J; Kugel, H; LeBlanc, B; McLean, A; Sabbagh, S A; Soukanovskii, V; Stotler, D P

2011-06-03T23:59:59.000Z

10

Direct X-B mode conversion for high-? national spherical torus experiment in nonlinear regime  

SciTech Connect (OSTI)

Electron Bernstein wave (EBW) can be effective for heating and driving currents in spherical tokamak plasmas. Power can be coupled to EBW via mode conversion of the extraordinary (X) mode wave. The most common and successful approach to study the conditions for optimized mode conversion to EBW was evaluated analytically and numerically using a cold plasma model and an approximate kinetic model. The major drawback in using radio frequency waves was the lack of continuous wave sources at very high frequencies (above the electron plasma frequency), which has been addressed. A future milestone is to approach high power regime, where the nonlinear effects become significant, exceeding the limits of validity for present linear theory. Therefore, one appropriate tool would be particle in cell (PIC) simulation. The PIC method retains most of the nonlinear physics without approximations. In this work, we study the direct X-B mode conversion process stages using PIC method for incident wave frequency f{sub 0}?=?15?GHz, and maximum amplitude E{sub 0}?=?10{sup 5?}V/m in the national spherical torus experiment (NSTX). The modelling shows a considerable reduction in X-B mode conversion efficiency, C{sub modelling}?=?0.43, due to the presence of nonlinearities. Comparison of system properties to the linear state reveals predominant nonlinear effects; EBW wavelength and group velocity in comparison with linear regime exhibit an increment around ?36% and 17%, respectively.

Ali Asgarian, M., E-mail: maliasgarian@ph.iut.ac.ir, E-mail: maa@msu.edu [Physics Department, Isfahan University of Technology, Isfahan 84156 (Iran, Islamic Republic of); Department of Electrical and Computer Engineering, Michigan State University, Michigan 48824-1226 (United States); Parvazian, A.; Abbasi, M. [Physics Department, Isfahan University of Technology, Isfahan 84156 (Iran, Islamic Republic of); Verboncoeur, J. P. [Department of Electrical and Computer Engineering, Michigan State University, Michigan 48824-1226 (United States)

2014-09-15T23:59:59.000Z

11

An Overview of Recent Results from the National Spherical Torus Experiment  

E-Print Network [OSTI]

Hopkins U Los Alamos NL Lawrence Livermore NL Lodestar MIT Nova Photonics, Inc. New York U Old Dominion U U Hiroshima U Hyogo U Kyoto U Kyushu U Kyushu Tokai U NIFS Niigata U U Tokyo JAEA Hebrew U Ioffe, Garching ASCR, Czech Rep U Quebec Supported by #12;Bell / NIFS seminar / 080916 2 "Spherical Torus" Extends

Princeton Plasma Physics Laboratory

12

Fast ion absorption of the high harmonic fast wave in the National Spherical Torus Experiment a...  

E-Print Network [OSTI]

the high harmonic fast wave #HHFW# and energetic particles in a spherical torus #ST# #Ref. 1# is a new, Princeton, New Jersey 08543 R. W. Harvey CompX, Del Mar, California 92014 T. K. Mau University of California, Columbia University, New York, New York 10027 J. Egedal Plasma Science and Fusion Center, Massachusetts

Egedal, Jan

13

Dynamical Evolution of Pedestal Parameters in ELMy H-mode in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

Characterizations of the pedestal parameter dynamics throughout the edge localized modes(ELM) cycles are performed on the National Spherical Torus Experiment (NSTX, [M. Ono et al., Nucl. Fusion 40, 557 (2000)]). A clear buildup of the pedestal height is observed between ELMs for three di erent plasma currents, which tends to saturate prior to the onset of ELM at low and medium plasma current. Similarly, the pedestal width increases with no clear evidence of saturation during an ELM cycle. The maximum pedestal gradient increases as a function of plasma current, reaches a nominal value after the ELM crash, and remains constant until the end of the ELM cycle. The pedestal height just prior to the onset of ELM is shown to increase quadratically with plasma current. The pedestal width ? is proportional to the square-root of the poloidal ? at the top of the pedestal. Coherent density uctuations strongly increasing at the plasma edge are observed to be maximum after the ELM crash and to decay during the rest of the ELM cycle. Finally, the pedestal parameters evolution during the ELM cycle as well as the scaling with Ip of the pedestal pressure prior to the onset ELM are found to be qualitatively consistent with the peeling ballooning theory.

Diallo, A; Kubota, S; Sontag, A; Osborne, T; Podesta, M; Bell, R E; LeBlanc, B P; Menard, J

2011-07-27T23:59:59.000Z

14

Physics Design of a 28 GHz Electron Heating System for the National Spherical Torus Experiment Upgrade  

SciTech Connect (OSTI)

A megawatt-level, 28 GHz electron heating system is being designed to support non-inductive (NI) plasma current (I{sub p}) start-up and local heating and current drive (CD) in H-mode discharges in the National Spherical Torus Experiment Upgrade (NSTX-U). The development of fully NI I{sub p} start-up and ramp-up is an important goal of the NSTX-U research program. 28 GHz electron cyclotron (EC) heating is predicted to rapidly increase the central electron temperature (T{sub e}(0)) of low density NI plasmas generated by Coaxial Helicity Injection (CHI). The increased T{sub e}(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. Also 28 GHz electron Bernstein wave (EBW) heating and CD can be used during the I{sub p} flat top in NSTX-U discharges when the plasma is overdense. Ray tracing and Fokker-Planck numerical simulation codes have been used to model EC and EBW heating and CD in NSTX-U. This paper presents a pre-conceptual design for the 28 GHz heating system and some of the results from the numerical simulations.

none,

2013-07-09T23:59:59.000Z

15

Physics design of a 28 GHz electron heating system for the National Spherical Torus experiment upgrade  

SciTech Connect (OSTI)

A megawatt-level, 28 GHz electron heating system is being designed to support non-inductive (NI) plasma current (I{sub p}) start-up and local heating and current drive (CD) in H-mode discharges in the National Spherical Torus Experiment Upgrade (NSTX-U). The development of fully NI I{sub p} start-up and ramp-up is an important goal of the NSTXU research program. 28 GHz electron cyclotron (EC) heating is predicted to rapidly increase the central electron temperature (T{sub e}(0)) of low density NI plasmas generated by Coaxial Helicity Injection (CHI). The increased T{sub e}(0) will significantly reduce the I{sub p} decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. Also 28 GHz electron Bernstein wave (EBW) heating and CD can be used during the I{sub p} flat top in NSTX-U discharges when the plasma is overdense. Ray tracing and Fokker-Planck numerical simulation codes have been used to model EC and EBW heating and CD in NSTX-U. This paper presents a pre-conceptual design for the 28 GHz heating system and some of the results from the numerical simulations.

Taylor, G.; Bertelli, N.; Ellis, R. A.; Gerhardt, S. P.; Hosea, J. C.; Poli, F. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Harvey, R. W. [CompX, Del Mar, California 92014 (United States); Raman, R. [University of Washington, Seattle, Washington 98195 (United States); Smirnov, A. P. [M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2014-02-12T23:59:59.000Z

16

Intermittent Divertor Filaments in the National Spherical Torus Experiment and Their Relation to Midplane Blobs  

SciTech Connect (OSTI)

While intermittent filamentary structures, also known as blobs, are routinely seen in the low-field-side scrape-off layer of the National Spherical Torus Experiment (NSTX) (Ono et al 2000 Nucl. Fusion 40 557), fine structured filaments are also seen on the lower divertor target plates of NSTX. These filaments, not associated with edge localized modes, correspond to the interaction of the turbulent blobs seen near the midplane with the divertor plasma facing components. The fluctuation level of the neutral lithium light observed at the divertor, and the skewness and kurtosis of its probability distribution function, is similar to that of midplane blobs seen in D?; e.g. increasing with increasing radii outside the outer strike point (OSP) (separatrix). In addition, their toroidal and radial movement agrees with the typical movement of midplane blobs. Furthermore, with the appropriate magnetic topology, i.e. mapping between the portion of the target plates being observed into the field of view of the midplane gas puff imaging diagnostic, very good correlation is observed between the blobs and the divertor filaments. The correlation between divertor plate filaments and midplane blobs is lost close to the OSP. This latter observation is consistent with the existence of magnetic shear disconnection due to the lower X-point, as proposed by Cohen and Ryutov (1997 Nucl. Fusion 37 621).

R.J. Maqueda, D.P. Stotler and the NSTX Team.

2010-05-19T23:59:59.000Z

17

A Megawatt-level 28z GHz Heating System For The National Spherical Torus Experiment Upgrade  

SciTech Connect (OSTI)

The National Spherical Torus Experiment Upgrade (NSTX-U) will operate at axial toroidal fields of < 1 T and plasma currents, Ip < 2 MA. The development of non-inductive (NI) plasmas is a major long-term research goal for NSTX-U. Time dependent numerical simulations of 28 GHz electron cyclotron (EC) heating of low density NI start-up plasmas generated by Coaxial Helicity Injection (CHI) in NSTX-U predict a significant and rapid increase of the central electron temperature (Te(0)) before the plasma becomes overdense. The increased Te(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. A megawatt-level, 28 GHz electron heating system is planned for heating NI start-up plasmas in NSTX-U. In addition to EC heating of CHI start-up discharges, this system will be used for electron Bernstein wave (EBW) plasma start-up, and eventually for EBW heating and current drive during the Ip flattop.

Taylor, Gary [PPPL

2014-04-01T23:59:59.000Z

18

Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment  

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

This paper describes techniques for measuring halo currents, and their associated toroidal peaking, in the National Spherical Torus Experiments [M. Ono, et. al, Nuclear Fusion 40, 557 (2000)]. The measurements are based on three techniques: (i) measurement of the toroidal field created by the poloidal halo current, either with segmented Rogowski coils or discrete toroidal field sensors, (ii) the direct measurement of halo currents into specially instrument tiles, and (iii) small Rogowski coils placed on the mechanical supports of in-vessel components. For the segmented Rogowski coils and discrete toroidal field detectors, it is shown that the toroidal peaking factor inferred from the data is significantly less than the peaking factor of the underlying halo current distribution, and a simple model is developed to relate the two. For the array of discrete toroidal field detectors and small Rogowski sensors, the compensation steps that are used to isolate the halo current signal are described. The electrical and mechanical design of compact under-tile resistive shunts and mini-Rogowski coils is described. Example data from the various systems is shown.

Gerhardt, S. P. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Fredrickson, E. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Guttadora, L. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Kaita, R. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Kugel, H. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Menard, J. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Takahashi, H. [Princeton Fusion Research LLC, Princeton, NJ (United States)

2011-10-06T23:59:59.000Z

19

Spherical torus fusion reactor  

DOE Patents [OSTI]

The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

Martin Peng, Y.K.M.

1985-10-03T23:59:59.000Z

20

Plasma Response to Lithium-Coated Plasma-Facing Components in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

Experiments in the National Spherical Torus Experiment (NSTX) have shown beneficial effects on the performance of divertor plasmas as a result of applying lithium coatings on the graphite and carbonfiber- composite plasma-facing components. These coatings have mostly been applied by a pair of lithium evaporators mounted at the top of the vacuum vessel which inject collimated streams of lithium vapor towards the lower divertor. In NBI-heated, deuterium H-mode plasmas run immediately after the application of lithium, performance modifications included decreases in the plasma density, particularly in the edge, and inductive flux consumption, and increases in the electron and ion temperatures and the energy confinement time. Reductions in the number and amplitude of ELMs were observed, including complete ELM suppression for periods up to 1.2 s, apparently as a result of altering the stability of the edge. However, in the plasmas where ELMs were suppressed, there was a significant secular increase in the effective ion charge Zeff and the radiated power as a result of increases in the carbon and medium-Z metallic impurities, although not of lithium itself which remained at a very low level in the plasma core, <0.1%. The impurity buildup could be inhibited by repetitively triggering ELMs with the application of brief pulses of an n = 3 radial field perturbation. The reduction in the edge density by lithium also inhibited parasitic losses through the scrape-off layer of ICRF power coupled to the plasma, enabling the waves to heat electrons in the core of H-mode plasmas produced by NBI. Lithium has also been introduced by injecting a stream of chemically stabilized, fine lithium powder directly into the scrape-off layer of NBI-heated plasmas. The lithium was ionized in the SOL and appeared to flow along the magnetic field to the divertor plates. This method of coating produced similar effects to the evaporated lithium but at lower amounts.

M.G. Bell, H.W. Kugel, R. Kaita, L.E. Zakharov, H. Schneider, B.P. LeBlanc, D. Mansfield, R.E. Bell, R. Maingi, S. Ding, S.M. Kaye, S.F. Paul, S.P. Gerhardt, J.M. Canik, J.C. Hosea, G. Taylor and the NSTX Research Team

2009-08-20T23:59:59.000Z

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21

Recent Progress on Spherical Torus Research  

SciTech Connect (OSTI)

The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A = R0/a) reduced to A ~ 1.5, well below the normal tokamak operating range of A ? 2.5. As the aspect ratio is reduced, the ideal tokamak beta ? (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as ? ~ 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural elongation ?, which makes its plasma shape appear spherical, the ST configuration can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to its longer term goal of attractive fusion energy power source. Since the start of the two megaampere class ST facilities in 2000, National Spherical Torus Experiment (NSTX) in the US and Mega Ampere Spherical Tokamak (MAST) in UK, active ST research has been conducted worldwide. More than sixteen ST research facilities operating during this period have achieved remarkable advances in all of fusion science areas, involving fundamental fusion energy science as well as innovation. These results suggest exciting future prospects for ST research both near term and longer term. The present paper reviews the scientific progress made by the worldwide ST research community during this new mega-ampere-ST era.

Ono, Masayuki [PPPL; Kaita, Robert [PPPL

2014-01-01T23:59:59.000Z

22

Efficient Coupling of Thermal Electron Bernstein Waves to the Ordinary Electromagnetic Mode on the National Spherical Torus Experiment (NSTX)  

SciTech Connect (OSTI)

Efficient coupling of thermal electron Bernstein waves (EBW) to ordinary mode (Omode) electromagnetic radiation has been measured in plasmas heated by energetic neutral beams and high harmonic fast waves in the National Spherical Torus Experiment (NSTX) [M. Ono, S. Kaye, M. Peng, et al., Proceedings 17th IAEA Fusion Energy Conference (IAEA, Vienna, Austria, 1999), Vol.3, p. 1135]. The EBW to electromagnetic mode coupling efficiency was measured to be 0.8 {+-} 0.2, compared to a numerical EBW modeling prediction of 0.65. The observation of efficient EBW coupling to O-mode, in relatively good agreement with numerical modeling, is a necessary prerequisite for implementing a proposed high power EBW current drive system on NSTX.

G. Taylor; P.C. Efthimion; B.P. LeBlanc; M.D. Carter; J.B. Caughman; J.B. Wilgen; J. Preinhaelter; R.W. Harvey; S.A. Sabbagh

2005-02-02T23:59:59.000Z

23

Reduced model prediction of electron temperature profiles in microtearing-dominated National Spherical Torus eXperiment plasmas  

SciTech Connect (OSTI)

A representative H-mode discharge from the National Spherical Torus eXperiment is studied in detail to utilize it as a basis for a time-evolving prediction of the electron temperature profile using an appropriate reduced transport model. The time evolution of characteristic plasma variables such as ?{sub e},??{sub e}{sup ?}, the MHD ? parameter, and the gradient scale lengths of T{sub e}, T{sub i}, and n{sub e} were examined as a prelude to performing linear gyrokinetic calculations to determine the fastest growing micro instability at various times and locations throughout the discharge. The inferences from the parameter evolutions and the linear stability calculations were consistent. Early in the discharge, when ?{sub e} and ?{sub e}{sup ?} were relatively low, ballooning parity modes were dominant. As time progressed and both ?{sub e} and ?{sub e}{sup ?} increased, microtearing became the dominant low-k{sub ?} mode, especially in the outer half of the plasma. There are instances in time and radius, however, where other modes, at higher-k{sub ?}, may, in addition to microtearing, be important for driving electron transport. Given these results, the Rebut-Lallia-Watkins (RLW) electron thermal diffusivity model, which is based on microtearing-induced transport, was used to predict the time-evolving electron temperature across most of the profile. The results indicate that RLW does a good job of predicting T{sub e} for times and locations where microtearing was determined to be important, but not as well when microtearing was predicted to be stable or subdominant.

Kaye, S. M., E-mail: skaye@pppl.gov; Guttenfelder, W.; Bell, R. E.; Gerhardt, S. P.; LeBlanc, B. P.; Maingi, R. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2014-08-15T23:59:59.000Z

24

A feasibility study for the spherical torus experiment  

SciTech Connect (OSTI)

Oak Ridge National Laboratory (ORNL) proposes to build the Spherical Torus Experiment (STX), a very low aspect ratio toroidal confinement device. This proposal concentrates on tokamak operation of the experiment; however, it can in principle be operated as a pinch or reversed-field pinch as well. As a tokamak, the spherical torus confines a plasma that is characterized by high toroidal beta, low poloidal beta, large natural elongation, high plasma current for a given edge q, and strong paramagnetism. These features combine to offer the possibility of a compact, low-field fusion device. The figure below shows that when compared to a conventional tokamak the spherical torus represents a major change in geometry. The primary goals of the experiment will be to demonstrate a capability for high beta (20%) in the first stability regime, to extend our knowledge of tokamak confinement scaling, and to test oscillating-field current drive. The experiment will operate in the high-beta, collisionless regime, which is achieved in STX at low temperatures because of the geometry. At a minimum, operation of STX will help to resolve fundamental questions regarding the scaling of beta and confinement in tokamaks. Complete success in this program would have a significant impact on toroidal fusion research in that it would demonstrate solutions to the problems of beta and steady-state operation in the tokamak. The proposed device has a major radius of 0.45 m, a toroidai field of 0.5 T, a plasma current of 900 kA, and heating by neutral beam injection. We estimate 30 months for design, construction, and assembly. The budget estimate, including contingency and escalation, is $6.8 million.

Lazarus, E [Oak Ridge National Laboratory (ORNL); Peng, Yueng Kay Martin [ORNL

1985-10-01T23:59:59.000Z

25

Flow and shear behavior in the edge and scrape-off layer of L-mode plasmas in National Spherical Torus Experiment  

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

Fluctuations in the edge and scrape-off layer (SOL) of L-mode plasmas in the National Spherical Torus Experiment (NSTX) [S. M. Kaye et al.,Phys. Plasmas 8, 1977 (2001)] as observed by the gas puff imaging (GPI) diagnostic are studied. Calculation of local, time resolved velocity maps using the Hybrid Optical Flow and Pattern Matching Velocimetry (HOP-V) code enables analysis of turbulent flow and shear behavior. Periodic reversals in the direction of the poloidal flow near the separatrix are observed. Also, poloidal velocities and their radial shearing rate are found to be well correlated with the fraction of D? light contained in the SOL, which acts as a measure of turbulent bursts. The spectra of GPI intensity and poloidal velocity both have a strong feature near 3 kHz, which appears to correspond with turbulent bursts. This mode exhibits a poloidal structure with poloidal wavenumber of 7.7 m-1 for GPI intensity and 3.4 m-1 for poloidal velocity, and the poloidal velocity fluctuations near 3 kHz remain coherent over length scales in excess of the turbulent scales. Furthermore, recent SOL Turbulence (SOLT) simulations find a parameter regime that exhibits periodic bursty transport and shares many qualitative similarities with the experimental data. Strong correlations between the shearing rate and the turbulent bursts are observed for time periods of ~ 2 ms, but the relationship is complicated by several factors. Finally, measurements of the radial profiles of the Reynolds shear stresses are reported. These radial profiles exhibit many similarities for several shots, and a region with positive radial gradient is seen to be coincident with local flow shear.

Sechrest, Y. [Univ. of Colorado, Boulder, CO (United States); Munsat, T. [Univ. of Colorado, Boulder, CO (United States); DIppolito, D. A. [Lodestar Research Corp., Boulder, CO (United States); Maqueda, R. J. [Princeton Plasma Physics Lab., NJ (United States); Myra, J. R. [Lodestar Research Corp., Boulder, CO (United States); Russell, D. [Lodestar Research Corp., Boulder, CO (United States); Zweben, S. J. [Princeton Plasma Physics Lab., NJ (United States)

2011-01-10T23:59:59.000Z

26

Electron Bernstein waves in spherical torus plasmas  

SciTech Connect (OSTI)

Propagation and absorption of the electron Bernstein waves (EBWs) in spherical tokamaks (STs) have been intensively discussed in recent years because the EBWs coupled with an externally launched electromagnetic beam seem to be the only opportunity for microwave plasma heating and current drive in the electron cyclotron (EC) frequency range in the STs. The whole problem of the electron Bernstein heating and current drive (EBWHCD) in spherical plasmas is naturally divided into three major parts: coupling of incident electromagnetic waves (EMWs) to the EBWs near the upper hybrid resonance (UHR) surface, propagation and absorption of the EBWs in the plasma interior and generation of noninductive current driven by the EBWs. The present paper is a brief survey of the most important theoretical and numerical results on the issue of EBWs.

Saveliev, A. N. [A.F.Ioffe Physico-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation)

2006-11-30T23:59:59.000Z

27

Modeling of Spherical Torus Plasmas for Liquid Lithium Wall Experiments  

SciTech Connect (OSTI)

Liquid metal walls have the potential to solve first-wall problems for fusion reactors, such as heat load and erosion of dry walls, neutron damage and activation, and tritium inventory and breeding. In the near term, such walls can serve as the basis for schemes to stabilize magnetohydrodynamic (MHD) modes. Furthermore, the low recycling characteristics of lithium walls can be used for particle control. Liquid lithium experiments have already begun in the Current Drive eXperiment-Upgrade (CDX-U). Plasmas limited with a toroidally localized limiter have been investigated, and experiments with a fully toroidal lithium limiter are in progress. A liquid surface module (LSM) has been proposed for the National Spherical Torus Experiment (NSTX). In this larger ST, plasma currents are in excess of 1 MA and a typical discharge radius is about 68 cm. The primary motivation for the LSM is particle control, and options for mounting it on the horizontal midplane or in the divertor region are under consideration. A key consideration is the magnitude of the eddy currents at the location of a liquid lithium surface. During plasma start up and disruptions, the force due to such currents and the magnetic field can force a conducting liquid off of the surface behind it. The Tokamak Simulation Code (TSC) has been used to estimate the magnitude of this effect. This program is a two dimensional, time dependent, free boundary simulation code that solves the MHD equations for an axisymmetric toroidal plasma. From calculations that match actual ST equilibria, the eddy current densities can be determined at the locations of the liquid lithium. Initial results have shown that the effects could be significant, and ways of explicitly treating toroidally local structures are under investigation.

R. Kaita; S. Jardin; B. Jones; C. Kessel; R. Majeski; J. Spaleta; R. Woolley; L. Zakharo; B. Nelson; M. Ulrickson

2002-01-29T23:59:59.000Z

28

Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U  

E-Print Network [OSTI]

- 1 - Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U R. KAITA of this concept, key liquid lithium-plasma interaction questions are being addressed in the CDX-U device[2 (PPPL) is a spherical torus (ST) dedicated to the exploration of liquid lithium as a potential solution

California at Los Angeles, University of

29

An Inexpensive Ohmic Transformer Firing Circuit for the CDXU Spherical Torus  

E-Print Network [OSTI]

1 An Inexpensive Ohmic Transformer Firing Circuit for the CDX­U Spherical Torus T. Munsat, R designed and modeled a simple, efficient circuit for delivering power to the CDX­U ohmic transformer, spherical tori) have traditionally driven plasma current by using the transformer action of a centrally

30

An Inexpensive Ohmic Transformer Firing Circuit for the CDX-U Spherical Torus  

E-Print Network [OSTI]

1 An Inexpensive Ohmic Transformer Firing Circuit for the CDX-U Spherical Torus T. Munsat, R designed and modeled a simple, efficient circuit for delivering power to the CDX-U ohmic transformer, spherical tori) have traditionally driven plasma current by using the transformer action of a centrally

31

National Spherical Torus Experiment NSTX UPGRADE PROJECT  

E-Print Network [OSTI]

test plans, and operating procedures relevant to the safe conduct of operations. It will also include not be applicable. PPPL uses ESHD 5008 (PPPL Environment, Safety & Health Manual) Section 11 ("Operations Hazard) Guiding Principle for Operations Authorization of experimental projects. The PPPL approval process

Princeton Plasma Physics Laboratory

32

Supported by National Spherical Torus Experiment  

E-Print Network [OSTI]

-Materials Interactions, Advanced Physics, Nuclear Component Testing Burning Plasma Physics ST offers compact geometry / ITER Operations Passive plates Blanket modules Port Control Coils Control Coils ITER vessel ITER plasma

33

Advanced tokamak reactors based on the spherical torus (ATR/ST). Preliminary design considerations  

SciTech Connect (OSTI)

Preliminary design results relating to an advanced magnetic fusion reactor concept based on the high-beta, low-aspect-ratio, spherical-torus tokamak are summarized. The concept includes resistive (demountable) toroidal-field coils, magnetic-divertor impurity control, oscillating-field current drive, and a flowing liquid-metal breeding blanket. Results of parametric tradeoff studies, plasma engineering modeling, fusion-power-core mechanical design, neutronics analyses, and blanket thermalhydraulics studies are described. The approach, models, and interim results described here provide a basis for a more detailed design. Key issues quantified for the spherical-torus reactor center on the need for an efficient drive for this high-current (approx.40 MA) device as well as the economic desirability to increase the net electrical power from the nominal 500-MWe(net) value adopted for the baseline system. Although a direct extension of present tokamak scaling, the stablity and transport of this high-beta (approx.0.3) plasma is a key unknown that is resoluble only by experiment. The spherical torus generally provides a route to improved tokamak reactors as measured by considerably simplified coil technology in a configuration that allows a realistic magnetic divertor design, both leading to increased mass power density and reduced cost.

Miller, R.L.; Krakowski, R.A.; Bathke, C.G.; Copenhaver, C.; Schnurr, N.M.; Engelhardt, A.G.; Seed, T.J.; Zubrin, R.M.

1986-06-01T23:59:59.000Z

34

First Observation Of ELM Pacing With Vertical Jogs In A Spherical Torus  

SciTech Connect (OSTI)

Experiments in a number of conventional aspect ratio tokamaks have been successful in pacing edge localized modes (ELMs) by rapid vertical jogging of the plasma. This paper demonstrates the first pacing of ELMs in a spherical torus plasma. Applied 30 Hz vertical jogs synchronized the ELMs with the upward motion of the plasma. 45 Hz jogs also lead to an increase in the ELM frequency, though the synchronization of the ELMs and jogs was unclear. A reduction in the ELM energy was observed at the higher driven ELM frequencies. __________________________________________________

Gerhardt, S P; Canik, J M; Maingi, R; Bell, R; Gates, d; Goldston, R; Hawryluk, R; Le Blanc, B P; Menard, J; Sontag, A C; Sabbagh, S

2010-07-15T23:59:59.000Z

35

Measured improvement of global magnetohydrodynamic mode stability at high-beta, and in reduced collisionality spherical torus plasmas  

SciTech Connect (OSTI)

Global mode stability is studied in high-? National Spherical Torus Experiment (NSTX) plasmas to avoid disruptions. Dedicated experiments in NSTX using low frequency active magnetohydrodynamic spectroscopy of applied rotating n?=?1 magnetic fields revealed key dependencies of stability on plasma parameters. Observations from previous NSTX resistive wall mode (RWM) active control experiments and the wider NSTX disruption database indicated that the highest ?{sub N} plasmas were not the least stable. Significantly, here, stability was measured to increase at ?{sub N}?l{sub i} higher than the point where disruptions were found. This favorable behavior is shown to correlate with kinetic stability rotational resonances, and an experimentally determined range of measured E??B frequency with improved stability is identified. Stable plasmas appear to benefit further from reduced collisionality, in agreement with expectation from kinetic RWM stabilization theory, but low collisionality plasmas are also susceptible to sudden instability when kinetic profiles change.

Berkery, J. W.; Sabbagh, S. A.; Balbaky, A. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Bell, R. E.; Diallo, A.; Gerhardt, S. P.; LeBlanc, B. P.; Manickam, J.; Menard, J. E.; Podest, M. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Betti, R. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

2014-05-15T23:59:59.000Z

36

Surface Treatment of a Lithium Limiter for Spherical Torus Plasma Experiments  

SciTech Connect (OSTI)

The concept of a flowing lithium first wall for a fusion reactor may lead to a significant advance in reactor design, since it could virtually eliminate the concerns with power density and erosion, tritium retention, and cooling associated with solid walls. As part of investigations to determine the feasibility of this approach, plasma interaction questions in a toroidal plasma geometry are being addressed in the Current Drive eXperiment-Upgrade (CDX-U) spherical torus (ST). The first experiments involved a toroidally local lithium limiter (L3). Measurements of pumpout rates indicated that deuterium pumping was greater for the L3 compared to conventional boron carbide limiters. The difference in the pumpout rates between the two limiter types decreased with plasma exposure, but argon glow discharge cleaning was able to restore the pumping effectiveness of the L3. At no point, however, was the extremely low recycling regime reported in previous lithium experiments achieved. This may be due to the much larger lithium surfaces that were exposed to the plasma in the earlier work. The possibility will be studied in the next set of CDX-U experiments, which are to be conducted with a large area, fully toroidal lithium limiter.

Kaita, R.; Majeski, R.; Doerner, R.; Antar, G.; Timberlake, J.; Spaleta, J.; Hoffman, D.; Jones, B.; Munsat, T.; Kugel, H.; Taylor, G.; Stutman, D.; Soukhanovskii, V.; Maingi, R.; Molesa, S.; Efthimion, P.; Menard, J.; Finkenthal, M.; Luckhardt, S.

2001-03-20T23:59:59.000Z

37

Spherical Torus Plasma Interactions with Large-area Liquid Lithium Surfaces in CDX-U  

SciTech Connect (OSTI)

The Current Drive Experiment-Upgrade (CDX-U) device at the Princeton Plasma Physics Laboratory (PPPL) is a spherical torus (ST) dedicated to the exploration of liquid lithium as a potential solution to reactor first-wall problems such as heat load and erosion, neutron damage and activation, and tritium inventory and breeding. Initial lithium limiter experiments were conducted with a toroidally-local liquid lithium rail limiter (L3) from the University of California at San Diego. Spectroscopic measurements showed a clear reduction of impurities in plasmas with the L3, compared to discharges with a boron carbide limiter. The evidence for a reduction in recycling was less apparent, however. This may be attributable to the relatively small area in contact with the plasma, and the presence of high-recycling surfaces elsewhere in the vacuum chamber. This conclusion was tested in subsequent experiments with a fully toroidal lithium limiter that was installed above the floor of the vacuum vessel. The new limiter covered over ten times the area of the L3 facing the plasma. Experiments with the toroidal lithium limiter have recently begun. This paper describes the conditioning required to prepare the lithium surface for plasma operations, and effect of the toroidal liquid lithium limiter on discharge performance.

R. Kaita; R. Majeski; M. Boaz; P. Efthimion; B. Jones; D. Hoffman; H. Kugel; J. Menard; T. Munsat; A. Post-Zwicker; V. Soukhanovskii; J. Spaleta; G. Taylor; J. Timberlake; R. Woolley; L. Zakharov; M. Finkenthal; D. Stutman; G. Antar; R. Doerner; S. Luckhardt; R. Maingi; M. Maiorano; S. Smith

2002-01-18T23:59:59.000Z

38

National Spherical Torus Experiment (NSTX) Construction, Commissioning, and Initial Operations  

E-Print Network [OSTI]

Poloidal Field (PF) coils, thermal insulation, and a center stack casing which forms the inner wall vacuum insulator assemblies which permit the use of Coaxial Helicity Injection (CHI) as one of the means, 5 sec Coaxial Helicity Injection (CHI) 50kA injection @ 1kV Neutral Beam Injection Upgrade (NBI) 5

39

National Spherical Torus Experiment (NSTX) Construction, Commissioning, and Initial Operations  

E-Print Network [OSTI]

cylinder, a pair of inner Poloidal Field (PF) coils, thermal insulation, and a center stack casing which of the machine via ceramic insulator assemblies which permit the use of Coaxial Helicity Injection (CHI) as one, 5 sec Coaxial Helicity Injection (CHI) 50kA injection @ 1kV Neutral Beam Injection Upgrade (NBI) 5

40

National Spherical Torus Experiment (NSTX) Power Supply Real Time Controller  

E-Print Network [OSTI]

derivatives. II. POWER SUPPLIES & CIRCUITS TO BE CONTROLLED A. Power Supplies NSTX utilizes the PPPL "Power Supply Sections" (PSS) which are electrically isolated from each other but subject to the same "Firing PSS by phase controlling the thyristor firing pulses in accordance with a Control Word received

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41

National Spherical Torus Experiment (NSTX) Power Supply Real Time Controller  

E-Print Network [OSTI]

systems according to pre­programmed current derivatives. II. POWER SUPPLIES & CIRCUITS TO BE CONTROLLED isolated from each other but subject to the same "Firing Generator" (FG). Each PSS Magnets Power Supply

42

National Spherical Torus Experiment-Upgrade SAFETY ASSESSMENT DOCUMENT  

E-Print Network [OSTI]

-00 Revision 6 DECEMBER 2014 Prepared by: _______________________ Jerry Levine Head, PPPL ESH&S Reviewed by Chair, PPPL ES&H Executive Board #12;#12;NSTX-U SAFETY ASSESSMENT DOCUMENT (SAD) Table of Contents 1

Princeton Plasma Physics Laboratory

43

National Spherical Torus Experiment NSTX CENTER STACK UPGRADE  

E-Print Network [OSTI]

Analysis (FMEA) 14 2.6.3 Structural Design Criteria 15 2.7 Material Selection 15 2.8 General Electrical

Princeton Plasma Physics Laboratory

44

R t f N l C t T ti Di i GReport of Nuclear Component Testing Discussion Group National Spherical Torus ProgramNational Spherical Torus Program  

E-Print Network [OSTI]

Office of Science R t f N l C t T ti Di i GReport of Nuclear Component Testing Discussion Group nuclear technology, SG1 leader UCLA DOE contact: Eckstrand, Steve, OFES #12;Nuclear Component Testing (NCT) aims to complement ITER mission and fill many DEMO R&D gaps · Mission of the Nuclear Component Testing

45

Parametric Dependence Of Fast-ion Transport Events On The National Spherical Torus Experiment  

SciTech Connect (OSTI)

Neutral-beam heated tokamak plasmas commonly have more than one third of the plasma kinetic energy in the non-thermal energetic beam ion population. This population of fast ions heats the plasma, provides some of the current drive, and can affect the stability (positively or negatively) of magnetohydrodynamic instabilities. This population of energetic ions is not in thermodynamic equilibrium, thus there is free-energy available to drive instabilities, which may lead to redistribution of the fast ion population. Understanding under what conditions beam-driven instabilities arise, and the extent of the resulting perturbation to the fast ion population, is important for predicting and eventually demonstrating non-inductive current ramp-up and sustainment in NSTX-U, as well as the performance of future fusion plasma experiments such as ITER. This paper presents an empirical approach towards characterizing the stability boundaries for some common energetic-ion-driven instabilities seen on NSTX.

Fredrickson, Erik; Gorelenkov, N. N.; Podesta, M.; Gerhardt, S. P.; Bell, R. E.; Diallo, A.; LeBlanc, B. [Princeton Plasma Physics Lab., NJ (United States)] [Princeton Plasma Physics Lab., NJ (United States); Bortolon, A. [Univ. of Tennessee, Knoxville, TN (United States)] [Univ. of Tennessee, Knoxville, TN (United States)

2014-03-31T23:59:59.000Z

46

Advances in High-harmonic Fast Wave Physics in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

Improved core high-harmonic fast wave (HHFW) heating at longer wavelengths and during start-up and plasma current ramp-up, has now been obtained by lowering the edge density with lithium wall conditioning, thereby moving the critical density for perpendicular fast-wave propagation away from the vessel wall. Lithium conditioning allowed significant HHFW core electron heating of deuterium neutral beam injection (NBI) fuelled H-mode plasmas to be observed for the first time. Large edge localized modes were observed immediately after the termination of rf power. Visible and infrared camera images show that fast wave interactions can deposit considerable rf energy on the outboard divertor. HHFW-generated parametric decay instabilities were observed to heat ions in the plasma edge and may be the cause for a measured drag on edge toroidal rotation during HHFW heating. A significant enhancement in neutron rate and fast-ion profile were measured in NBI-fuelled plasmas when HHFW heating was applied. __________________________________________________

Taylor, G; Hosea, J C; LeBlanc, B P; Phillips, C K; Podesta, M; Valeo, E J; Wilson, J R; Ahn, J -W; Chen, G; Green, D L; Jaeger, E F; Maingi, R; Ryan, P M; Wilgen, J B; Heidbrink, W W; Liu, D; Bonoli, P T; Brecht, T; Choi, M

2009-12-01T23:59:59.000Z

47

Physics Design Requirements for the National Spherical Torus Experiment Liquid Lithium Divertor  

SciTech Connect (OSTI)

Recent NSTX high power divertor experiments have shown significant and recurring benefits of solid lithium coatings on PFC's to the performance of divertor plasmas in both L- and H- mode confinement regimes heated by high-power neutral beams. The next step in this work is installation of a liquid lithium divertor (LLD) to achieve density control for inductionless current drive capability (e.g., about a 15-25% ne decrease from present highest non-inductionless fraction discharges which often evolve toward the density limit, ne/nGW~1), to enable ne scan capability (x2) in the H-mode, to test the ability to operate at significantly lower density for future ST-CTF reactor designs (e.g., ne/nGW = 0.25), and eventually to investigate high heat-flux power handling (10 MW/m2) with longpulse discharges (>1.5s). The first step (LLD-1) physics design encompasses the desired plasma requirements, the experimental capabilities and conditions, power handling, radial location, pumping capability, operating temperature, lithium filling, MHD forces, and diagnostics for control and characterization.

Kugel, W.; Bell, M.; Berzak,L.; Brooks, A.; Ellis, R.; Gerhardt, S.; Harjes, H.; Kaita, R.; Kallman, J.; Maingi, R.; Majeski, R.; Mansfield, D.; Menard, J.; Nygren,R. E.; Soukhanovskii, V.; Stotler, D.; Wakeland, P.; Zakharov L. E.

2008-09-26T23:59:59.000Z

48

National Spherical Torus Experiment (NSTX) | U.S. DOE Office of Science  

Office of Science (SC) Website

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman, 1960 The ErnestLouisMichael J.| U.S.Nathaniel

49

Fast ion absorption of the high harmonic fast wave in the National Spherical Torus Experimenta...  

E-Print Network [OSTI]

, Princeton, New Jersey 08543 R. W. Harvey CompX, Del Mar, California 92014 T. K. Mau University of California, Columbia University, New York, New York 10027 J. Egedal Plasma Science and Fusion Center, Massachusetts on Energetic Particles in Magnetic Confinement Systems, 2000, p. 109 and CONBEAM J. Egedal et al., Phys

Egedal, Jan

50

H-mode threshold and dynamics in the National Spherical Torus Experimenta...  

E-Print Network [OSTI]

prominent ``ears'' which can be sustained for many energy confinement times, E , in the absence of ELMs Laboratory, Los Alamos, New Mexico 87545 6 Columbia University, New York, New York 10027 7 Johns Hopkins toroidal field at the geometric radius, due to the reduced pressure peaking factor and improved energy con

California at San Diego, University of

51

Closeout Report for theCloseout Report for the National Spherical Torus  

E-Print Network [OSTI]

in recommendations to improve techniques for soldering cooling tubes in the TF conductor to prevent flux from techniques (e.

Princeton Plasma Physics Laboratory

52

DOEIEA-1108 ENVIRONMENTAL ASSESSMENT THE NATIONAL SPHERICAL TOKAMAK...  

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

as the existing Tokamak Fusion Test Reactor, TFTR, or the proposed International Thermonuclear Experimental Reactor, ITER) and operate at high plasma pressures, spherical...

53

Scientific Opportunities and Challenges in the Upgraded National Spherical  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmitted forHighlights Nuclear Physics (NP)Data Movement enabledTorus

54

Liquid Lithium Divertor and Scrape-Off-Layer Interactions on the National Spherical Torus Experiment: 2010 ? 2013 Progress Report  

SciTech Connect (OSTI)

The implementation of the liquid Lithium Divertor (LLD) in NSTX presented a unique opportunity in plasma-material interactions studies. A high density Langmuir Probe (HDLP) array utilizing a dense pack of triple Langmuir probes was built at PPPL and the electronics designed and built by UIUC. It was shown that the HDLP array could be used to characterize the modification of the EEDF during lithium experiments on NSTX as well as characterize the transient particle loads during lithium experiments as a means to study ELMs. With NSTX being upgraded and a new divertor being installed, the HDLP array will not be used in NSTX-U. However UIUC is currently helping to develop two new systems for depositing lithium into NSTX-U, a Liquid Lithium Pellet Dripper (LLPD) for use with the granular injector for ELM mitigation and control studies as well as an Upward-Facing Lithium Evaporator (U-LITER) based on a flash evaporation system using an electron beam. Currently UIUC has Daniel Andruczyk Stationed at PPPL and is developing these systems as well as being involved in preparing the Materials Analysis Particle Probe (MAPP) for use in LTX and NSTX-U. To date the MAPP preparations have been completed. New sample holders were designed by UIUC?s Research Engineer at PPPL and manufactured at PPPL and installed. MAPP is currently being used on LTX to do calibration and initial studies. The LLPD has demonstrated that it can produce pellets. There is still some adjustments needed to control the frequency and particle size. Equipment for the U-LITER has arrived and initial test are being made of the electron beam and design of the U-LITER in progress. It is expected to have these ready for the first run campaign of NSTX-U.

None

2013-08-27T23:59:59.000Z

55

Continuous Improvement of H-Mode Discharge Performance with Progressively Increasing Lithium Coatings in the National Spherical Torus Experiment  

E-Print Network [OSTI]

-wall interactions. Recently, there is growing use of lithium coatings, in particular, to control edge recyclingContinuous Improvement of H-Mode Discharge Performance with Progressively Increasing Lithium September 2011) Lithium wall coatings have been shown to reduce recycling, improve energy confinement

Princeton Plasma Physics Laboratory

56

Experimental studies on fast-ion transport by Alfvn wave avalanches on the National Spherical Torus Experimenta...  

E-Print Network [OSTI]

disagreement suggests that nonlinearities may compromise a direct comparison between experiment and linear for reactors such as ITER, where alpha particles originate from fusion reac- tions with an energy of 3.5 Me the behavior of a fusion reactor. Waves in the Alfvén frequency range are well known for their potential

Heidbrink, William W.

57

Experimental studies on fast-ion transport by Alfven wave avalanches on the National Spherical Torus Experiment  

E-Print Network [OSTI]

-linearities may compromise a direct comparison between experiment and theory. PACS numbers: I. INTRODUCTION a linear magneto-hydrodynamics stability code. The comparison with experimental data suggests that non or neutral beams (NB), may open new avenues to control the behavior of a fusion reactor. Paper GI1 1, Bull

Princeton Plasma Physics Laboratory

58

Spherical Torus (Spherical Tokamak) on the Path to Fusion Energy  

E-Print Network [OSTI]

USBPO-ITPA activities in preparation for burning plasma research in ITER using physics breadth provided and benefits from USBPO-ITPA in preparing for burning plasma research on ITER "Locked mode" threshold n

59

Science and Technology of the 10-MA Spherical Tori  

SciTech Connect (OSTI)

The Spherical Torus (ST) configuration has recently emerged as an example of confinement concept innovation that enables attractive steps in the development of fusion energy. The scientific potential for the ST has been indicated by recent encouraging results from START,2 CDX-U, and HIT. The scientific principles for the D-fueled ST will soon be tested by NSTX (National Spherical Torus Experiment3) in the U.S. and MAST (Mega-Amp Spherical Tokamak4) in the U.K. at the level of l-2 MA in plasma current. More recently, interest has grown in the U.S. in the possibility of near-term ST fusion burn devices at the level of 10 MA in plasma current. The missions for these devices would be to test burning plasma performance in a small, pulsed D-T-fueled ST (i.e., DTST) and to develop fusion energy technologies in a small steady state ST-based Volume Neutron Source (VNS). This paper reports the results of analysis of the key science and technology issues for these devices.

Peng, Y-K.M.

1999-11-14T23:59:59.000Z

60

Characteristics of Energy Transport of Li-conditioned and non-Li-conditioned Plasmas in the National Spherical Torus Experiment (NSTX)  

SciTech Connect (OSTI)

The transport properties of NSTX plasmas obtained during the 2008 experimental cam- paign have been studied and are reported here. Transport trends and dependences have been isolated, and it is found that both electron and ion energy transport coefficients have strong dependences on local values of n?T, which in turn is strongly dependent on local current density profile. Without identifying this dependence, it is difficult to identify others, such as the dependence of transport coefficients on Bp (or q), Ip and Pheat. In addition, a comparison between discharges with and without Lithium wall conditioning has been made. While the trends in the two sets of data are similar, the thermal transport loss, especially in the electron channel, is found to strongly depend on the amount of Lithium deposited, decreasing by up to 50% of its no-Lithium value.

Ding, S.; Kaye, S. M.; Bell, R. E.; Kaita, R.; Kugel, H.; LeBlanc, B. P.; Paul, S.; Wan, B.

2009-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Thermal Fluid Multiphysics Optimization of Spherical Tokamak  

SciTech Connect (OSTI)

An experimental Fusion Nuclear Science Facility (FNSF) is required that will create the environment that simultaneously achieves high energy neutrons and high ion fluence necessary in order to bridge the gaps from ITER to the realization of a fusion nuclear power plant. One concept for achieving this is a high duty cycle spherical torus. This study will focus on thermal modeling of the spherical torus centerpost using computational fluid dynamics to effectively model the thermal transfer of the cooling fluid to the centerpost. The design of the fluid channels is optimized in order to minimize the temperature in the centerpost. Results indicate the feasibility of water cooling for a long-pulse spherical torus FNSF.

Lumsdaine, Arnold [ORNL; Tipton, Joseph B [ORNL; Peng, Yueng Kay Martin [ORNL

2012-01-01T23:59:59.000Z

62

Physics Basis for a Spherical Torus Power Plant  

E-Print Network [OSTI]

exhaust and plasma operating regime. Overall systems optimization leads to a choice of aspect ratio A = 1 #12; 1 Introduction The most signi#12;cant di#11;erence between the ARIES-ST optimization presently under consideration and other advanced tokamak reactor concepts studied recently, such as ARIES-RS [1

63

3D TORUS V1.0  

Energy Science and Technology Software Center (OSTI)

002440MLTPL00 3D Torus Routing Engine Module for OFA OpenSM v. 1.0 http://www.openfabrics.org/git?p=sashak/management.git;a=sum

64

Initial Data for General Relativity Containing a Marginally Outer Trapped Torus  

E-Print Network [OSTI]

Asymptotically flat, time-symmetric, axially symmetric and conformally flat initial data for vacuum general relativity are studied numerically on $R^3$ with the interior of a standard torus cut out. By the choice of boundary condition the torus is marginally outer trapped, and thus a surface of minimal area. Apart from pure scaling the standard tori are parameterized by a radius $a\\in [0,1]$, where $a=0$ corresponds to the limit where the boundary torus degenerates to a circle and $a=1$ to a torus that touches the axis of symmetry. Noting that these tori are the orbits of a $U(1)\\times U(1)$ conformal isometry allows for a simple scheme to solve the constraint, involving numerical solution of only ordinary differential equations.The tori are unstable minimal surfaces (i.e. only saddle points of the area functional) and thus can not be apparent horizons, but are always surrounded by an apparent horizon of spherical topology, which is analyzed in the context of the hoop conjecture and isoperimetric inequality for black holes.

Sascha Husa

1996-06-15T23:59:59.000Z

65

A note on geodesic foliations on the torus Pierre Mounoud  

E-Print Network [OSTI]

A note on geodesic foliations on the torus Pierre Mounoud R´esum´e : Nous ´etudions les propri´et´es de leur feuilletages orthogonaux. Abstract: We look at geodesic foliations on the Lorentzian torus with leaves of different kind. We prove that they do not exist if the torus is geodesically

Mounoud, Pierre

66

Nanoparticle shape reconstruction by solving the direct and inverse small-angle scattering problems for a unit potential localized inside a torus  

SciTech Connect (OSTI)

The simplest doubly connected surface of revolution (torus) is used as an example to demonstrate the possibility of stable reconstruction a three-dimensional homogeneous body defined by a unit potential U(r) using a spherically averaged small-angle scattering (SAS) curve I(s). Annealing Monte Carlo simulations are performed without using prior information about nanoparticle shape and size. Exact and approximate expressions are obtained for the form factor of a torus. It is shown graphically that the exact and approximate SAS form-factor curves agree for an experimentally accessible scattering region. Examples are given.

Amarantov, S. V. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)], E-mail: amarantov_s@mail.ru

2009-04-15T23:59:59.000Z

67

FY 2005 Miniature Spherical Retroreflectors Final Report  

SciTech Connect (OSTI)

Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniature spherical retroreflectors using the unique optical and material properties of chalcogenide glass to reduce both performance limiting spherical and chromatic aberrations. The optimized optical performance will provide efficient signal retroreflection that enables a broad range of remote detection scenarios for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications. Miniature spherical retroreflectors can be developed to aid in the detection of signatures of nuclear proliferation or other chemical vapor or radiation signatures. Miniature spherical retroreflectors are not only well suited to traditional bistatic LIDAR methods for chemical plume detection and identification, but could enable remote detection of difficult semi-volatile chemical materials or low level radiation sources.

Anheier, Norman C.; Bernacki, Bruce E.; Johnson, Bradley R.; Riley, Brian J.; Sliger, William A.

2005-12-01T23:59:59.000Z

68

Electrodynamic spherical harmonic  

E-Print Network [OSTI]

Electrodynamic spherical harmonic is a second rank tensor in three-dimensional space. It allows to separate the radial and angle variables in vector solutions of Maxwell's equations. Using the orthonormalization for electrodynamic spherical harmonic, a boundary problem on a sphere can be easily solved.

Andrey Novitsky

2008-03-28T23:59:59.000Z

69

Spherical neutron generator  

DOE Patents [OSTI]

A spherical neutron generator is formed with a small spherical target and a spherical shell RF-driven plasma ion source surrounding the target. A deuterium (or deuterium and tritium) ion plasma is produced by RF excitation in the plasma ion source using an RF antenna. The plasma generation region is a spherical shell between an outer chamber and an inner extraction electrode. A spherical neutron generating target is at the center of the chamber and is biased negatively with respect to the extraction electrode which contains many holes. Ions passing through the holes in the extraction electrode are focused onto the target which produces neutrons by D-D or D-T reactions.

Leung, Ka-Ngo

2006-11-21T23:59:59.000Z

70

Minimal Liouville Gravity on the Torus via Matrix Models  

E-Print Network [OSTI]

In this paper we use recent results on resonance relations between the matrix models and the minimal Liouville gravity to compute the torus correlation numbers in (3,p) minimal Liouville gravity. Namely, we calculate the torus generating partition function of the (3,p) matrix models and use it to obtain the one- and two-point correlation numbers in the minimal Liouville gravity.

Lev Spodyneiko

2014-07-14T23:59:59.000Z

71

Arithmetic functions in torus and tree networks  

DOE Patents [OSTI]

Methods and systems for performing arithmetic functions. In accordance with a first aspect of the invention, methods and apparatus are provided, working in conjunction of software algorithms and hardware implementation of class network routing, to achieve a very significant reduction in the time required for global arithmetic operation on the torus. Therefore, it leads to greater scalability of applications running on large parallel machines. The invention involves three steps in improving the efficiency and accuracy of global operations: (1) Ensuring, when necessary, that all the nodes do the global operation on the data in the same order and so obtain a unique answer, independent of roundoff error; (2) Using the topology of the torus to minimize the number of hops and the bidirectional capabilities of the network to reduce the number of time steps in the data transfer operation to an absolute minimum; and (3) Using class function routing to reduce latency in the data transfer. With the method of this invention, every single element is injected into the network only once and it will be stored and forwarded without any further software overhead. In accordance with a second aspect of the invention, methods and systems are provided to efficiently implement global arithmetic operations on a network that supports the global combining operations. The latency of doing such global operations are greatly reduced by using these methods.

Bhanot, Gyan (Princeton, NJ); Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Vranas, Pavlos M. (Bedford Hills, NY)

2007-12-25T23:59:59.000Z

72

A Novel Demountable TF Joint Design for Low Aspect Ratio Spherical Torus Tokamaks  

SciTech Connect (OSTI)

A novel shaped design for the radial conductors and demountable electrical joints connecting inner and outer legs of copper TF system conductors in low aspect ratio tokamaks is described and analysis results are presented. Specially shaped designs can optimize profiles of electrical current density, magnetic force, heating, and mechanical stress.

Robert D. Woolley

2009-06-11T23:59:59.000Z

73

A Novel Demountable TF Joint Design for Low Aspect Ratio Spherical Torus Tokamaks  

SciTech Connect (OSTI)

A novel shaped design for the radial conductors and demountable electrical joints connecting inner and outer legs of copper TF system conductors in low aspect ratio tokamaks is described and analysis results are presented. Specially shaped designs can optimize profiles of electrical current density, magnetic force, heating, and mechanical stress.

R.D. Woolley

2009-05-29T23:59:59.000Z

74

Effects of Large Area Liquid Lithium Limiters on Spherical Torus Plasmas  

SciTech Connect (OSTI)

Use of a large-area liquid lithium surface as a first wall has significantly improved the plasma performance in the Current Drive Experiment-Upgrade (CDX-U) at the Princeton Plasma Physics Laboratory. Previous CDX-U experiments with a partially-covered toroidal lithium limiter tray have shown a decrease in impurities and the recycling of hydrogenic species. Improvements in loading techniques have permitted nearly full coverage of the tray surface with liquid lithium. Under these conditions, there was a large drop in the loop voltage needed to sustain the plasma current. The data are consistent with simulations that indicate more stable plasmas having broader current profiles, higher temperatures, and lowered impurities with liquid lithium walls. As further evidence for reduced recycling with a liquid lithium limiter, the gas puffing had to be increased by up to a factor of eight for the same plasma density achieved with an empty toroidal tray limiter.

R. Kaita; R. Majeski; M. Boaz; P. Efthimion; G. Gettelfinger; T. Gray; D. Hoffman; S. Jardin; H. Kugel; P. Marfuta; T. Munsat; C. Neumeyer; S. Raftopoulos; V. Soukhanovskii; J. Spaleta; G. Taylor; J. Timberlake; R. Woolley; L. Zakharov; M. Finkenthal; D. Stutman; L. Delgado-Aparicio; R.P. Seraydarian; G. Antar; R. Doerner; S. Luckhardt; M. Baldwin; R.W. Conn; R. Maingi; M. Menon; R. Causey; D. Buchenauer; M. Ulrickson; B. Jones; D. Rodgers

2004-06-07T23:59:59.000Z

75

An Inexpensive Ohmic Transformer Firing Circuit for the CDX-U Spherical Torus  

SciTech Connect (OSTI)

We have designed and modeled a simple, efficient circuit for delivering power to the CDX-U ohmic transformer solenoid. Inexpensive electrolytic capacitors are used to provide the bulk of the stored energy. One small high-voltage oil-filled capacitor bank is used in the ignitron-based circuit. Several design objectives are met, including the production of a solenoid current waveform well suited to the breakdown and ohmic current-drive of a tokamak plasma, making efficient use of the available loop volt-seconds. The electrolytic capacitors are protected from reverse-bias conditions, and the ohmic solenoid is protected from voltages above 1 kV, well within the voltage rating, under normal operation and any forseeable fault conditions.

R. Majeski; T. Munsat

1999-10-01T23:59:59.000Z

76

Spherical waves r Legendre polynomials  

E-Print Network [OSTI]

1 Impedance · Spherical waves r er e e Impedance · Legendre polynomials P0(x) = 1 P1(x) = x P2(x · Spherical waves ­ Spherical Hankel functions hn (2)(kr)=jn(kr)-iyn(kr) Impedance · Spherical waves Order: 0 1 4 Circumferential And azimuthal: 0,0 1,1 3,2 #12;3 Impedance · Spherical waves ­ Arbitrary

Berlin,Technische Universität

77

Fermions in spherical field theory  

E-Print Network [OSTI]

We derive the spherical field formalism for fermions. We find that the spherical field method is free from certain difficulties which complicate lattice calculations, such as fermion doubling, missing axial anomalies, and computational problems regarding internal fermion loops.

Dean Lee

1999-01-07T23:59:59.000Z

78

Hollow spherical shell manufacture  

DOE Patents [OSTI]

A process for making a hollow spherical shell of silicate glass composition in which an aqueous suspension of silicate glass particles and an immiscible liquid blowing agent is placed within the hollow spherical cavity of a porous mold. The mold is spun to reduce effective gravity to zero and to center the blowing agent, while being heated so as to vaporize the immiscible liquid and urge the water carrier of the aqueous suspension to migrate into the body of the mold, leaving a green shell compact deposited around the mold cavity. The green shell compact is then removed from the cavity, and is sintered for a time and a temperature sufficient to form a silicate glass shell of substantially homogeneous composition and uniform geometry.

O'Holleran, Thomas P. (Belleville, MI)

1991-01-01T23:59:59.000Z

79

Hollow spherical shell manufacture  

DOE Patents [OSTI]

A process is disclosed for making a hollow spherical shell of silicate glass composition in which an aqueous suspension of silicate glass particles and an immiscible liquid blowing agent is placed within the hollow spherical cavity of a porous mold. The mold is spun to reduce effective gravity to zero and to center the blowing agent, while being heated so as to vaporize the immiscible liquid and urge the water carrier of the aqueous suspension to migrate into the body of the mold, leaving a green shell compact deposited around the mold cavity. The green shell compact is then removed from the cavity, and is sintered for a time and a temperature sufficient to form a silicate glass shell of substantially homogeneous composition and uniform geometry. 3 figures.

O'Holleran, T.P.

1991-11-26T23:59:59.000Z

80

Nostos - Spherical TPCs  

E-Print Network [OSTI]

A new concept, the spherical TPC, presents unique advantages when low energy neutrinos are to be detected. Some of the applications are: a) observation of the e oscillation when emitted by a tritium source ( = 14 keV) in a 10 m radius sphere. This project, baptized NOSTOS, intends to give the mixing angle 13, the Weinberg angle and a much lower limit (energy (pp - 7Be) solar neutrinos.

Gorodetzky, P

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Efficient Subtorus Processor Allocation in a Multi-Dimensional Torus  

SciTech Connect (OSTI)

Processor allocation in a mesh or torus connected multicomputer system with up to three dimensions is a hard problem that has received some research attention in the past decade. With the recent deployment of multicomputer systems with a torus topology of dimensions higher than three, which are used to solve complex problems arising in scientific computing, it becomes imminent to study the problem of allocating processors of the configuration of a torus in a multi-dimensional torus connected system. In this paper, we first define the concept of a semitorus. We present two partition schemes, the Equal Partition (EP) and the Non-Equal Partition (NEP), that partition a multi-dimensional semitorus into a set of sub-semitori. We then propose two processor allocation algorithms based on these partition schemes. We evaluate our algorithms by incorporating them in commonly used FCFS and backfilling scheduling policies and conducting simulation using workload traces from the Parallel Workloads Archive. Specifically, our simulation experiments compare four algorithm combinations, FCFS/EP, FCFS/NEP, backfilling/EP, and backfilling/NEP, for two existing multi-dimensional torus connected systems. The simulation results show that our algorithms (especially the backfilling/NEP combination) are capable of producing schedules with system utilization and mean job bounded slowdowns comparable to those in a fully connected multicomputer.

Weizhen Mao; Jie Chen; William Watson

2005-11-30T23:59:59.000Z

82

CHARGED TORI IN SPHERICAL GRAVITATIONAL AND DIPOLAR MAGNETIC FIELDS  

SciTech Connect (OSTI)

A Newtonian model of non-conductive, charged, perfect fluid tori orbiting in combined spherical gravitational and dipolar magnetic fields is presented and stationary, axisymmetric toroidal structures are analyzed. Matter in such tori exhibits a purely circulatory motion and the resulting convection carries charges into permanent rotation around the symmetry axis. As a main result, we demonstrate the possible existence of off-equatorial charged tori and equatorial tori with cusps that also enable outflows of matter from the torus in the Newtonian regime. These phenomena qualitatively represent a new consequence of the interplay between gravity and electromagnetism. From an astrophysical point of view, our investigation can provide insight into processes that determine the vertical structure of dusty tori surrounding accretion disks.

Slany, P.; Kovar, J.; Stuchlik, Z. [Institute of Physics, Faculty of Philosophy and Science, Silesian University in Opava Bezrucovo nam. 13, CZ-746 01 Opava (Czech Republic)] [Institute of Physics, Faculty of Philosophy and Science, Silesian University in Opava Bezrucovo nam. 13, CZ-746 01 Opava (Czech Republic); Karas, V., E-mail: petr.slany@fpf.slu.cz [Astronomical Institute, Academy of Sciences, Bocni II, Prague CZ-141 31 (Czech Republic)

2013-03-01T23:59:59.000Z

83

E-Print Network 3.0 - advanced studies torus Sample Search Results  

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

mention of future work in Section 6. 2 Torus Network Model In this study, the simulation model... focused the strong scaling study on a 16-million-node torus and then the 1-...

84

Introduction to spherical field theory  

E-Print Network [OSTI]

Spherical field theory is a new non-perturbative method for studying quantum field theories. It uses the spherical partial wave expansion to reduce a general d-dimensional Euclidean field theory into a set of coupled one-dimensional systems. The coupled one-dimensional systems are then converted to partial differential equations and solved numerically. We demonstrate the methods of spherical field theory by analyzing Euclidean phi^4 theory in two dimensions.

Dean Lee

1998-11-12T23:59:59.000Z

85

ccsd-00003224,version1-4Nov2004 Clifton-Pohl torus and geodesic completeness  

E-Print Network [OSTI]

ccsd-00003224,version1-4Nov2004 Clifton-Pohl torus and geodesic completeness by a 'complex' point generalization of the idea of completeness guarantee geodesic completeness of Clifton- Pohl torus; we explicitely compute all of its geodesics. Keywords: Clifton-Pohl torus, geodesic completeness, holomorphic metric

Paris-Sud XI, Université de

86

Nonlinear spherical Alfven waves  

E-Print Network [OSTI]

We present an one-dimensional numerical study of Alfven waves propagating along a radial magnetic field. Neglecting losses, any spherical Alfven wave, no matter how small its initial amplitude is, becomes nonlinear at sufficiently large radii. From previous simulations of Alfven waves in plane parallel atmospheres we did expect the waves to steepen and produce current sheets in the nonlinear regime, which was confirmed by our new calculations. On the other hand we did find that even the least nonlinear waves were damped out almost completely before 10 solar radii. A damping of that kind is required by models of Alfven wave-driven winds from old low-mass stars as these winds are mainly accelerated within a few stellar radii.

Ulf Torkelsson; G. Christopher Boynton

1997-09-23T23:59:59.000Z

87

Torus-Margo Pits Help Conifers Compete with Angiosperms  

E-Print Network [OSTI]

. The reduction in resistivity achieved by the torus-margo pit membrane is equivalent to a 7.7-fold increase the number of times water must flow through high-resistance pits that link conduits end-to-end. Accordingly, the tracheid-based wood of conifers should have much higher flow resistance per length (resistivity) than

Hacke, Uwe

88

UCID-20974 Spherical Explosions  

Office of Scientific and Technical Information (OSTI)

be those of the Laboratory. Work prrformed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. 7 ' ....

89

Spherical Casimir pistons  

E-Print Network [OSTI]

A piston is introduced into a spherical lune Casimir cavity turning it into two adjacent lunes separated by the (hemispherical) piston. On the basis of zeta function regularisation, the vacuum energy of the arrangement is finite for conformal propagation in space-time. For even spheres this energy is independent of the angle of the lune. For odd dimensions it is shown that for all Neumann, or all Dirichlet, boundary conditions the piston is attracted or repelled by the nearest wall if d=3,7,... or if d=1,5,..., respectively. For hybrid N-D conditions these requirements are switched. If a mass is added, divergences arise which render the model suspect. The analysis, however, is relatively straightforward and involves the Barnes zeta function. The extension to finite temperatures is made and it is shown that for the 3,7,... series of odd spheres, the repulsion by the walls continues but that, above a certain temperature, the free energy acquires two minima symmetrically placed about the mid point.

J. S. Dowker

2011-02-23T23:59:59.000Z

90

UCID-20974 Spherical Explosions  

Office of Scientific and Technical Information (OSTI)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation InInformation In closing, an National Carbon Capture Center at ,i ThisEnergy

91

METRIC CHARACTERIZATIONS OF SPHERICAL AND EUCLIDEAN BUILDINGS  

E-Print Network [OSTI]

BUILDINGS Ruth Charney and Alexander Lytchak 0 of spaces satisfying CAT-inequalities are spherical and Euclidean buildings which come equipped with a natural piecewise spherical or Euclidean metric. Buildings also satisfy other nice metric properties

Charney, Ruth

92

MODELING RESULTS FROM CESIUM ION EXCHANGE PROCESSING WITH SPHERICAL RESINS  

SciTech Connect (OSTI)

Ion exchange modeling was conducted at the Savannah River National Laboratory to compare the performance of two organic resins in support of Small Column Ion Exchange (SCIX). In-tank ion exchange (IX) columns are being considered for cesium removal at Hanford and the Savannah River Site (SRS). The spherical forms of resorcinol formaldehyde ion exchange resin (sRF) as well as a hypothetical spherical SuperLig{reg_sign} 644 (SL644) are evaluated for decontamination of dissolved saltcake wastes (supernates). Both SuperLig{reg_sign} and resorcinol formaldehyde resin beds can exhibit hydraulic problems in their granular (nonspherical) forms. SRS waste is generally lower in potassium and organic components than Hanford waste. Using VERSE-LC Version 7.8 along with the cesium Freundlich/Langmuir isotherms to simulate the waste decontamination in ion exchange columns, spherical SL644 was found to reduce column cycling by 50% for high-potassium supernates, but sRF performed equally well for the lowest-potassium feeds. Reduced cycling results in reduction of nitric acid (resin elution) and sodium addition (resin regeneration), therefore, significantly reducing life-cycle operational costs. These findings motivate the development of a spherical form of SL644. This work demonstrates the versatility of the ion exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. The value of a resin with increased selectivity for cesium over potassium can be assessed for further development.

Nash, C.; Hang, T.; Aleman, S.

2011-01-03T23:59:59.000Z

93

Spherically symmetric scalar field collapse  

E-Print Network [OSTI]

It is shown that a scalar field, minimally coupled to gravity may have collapsing modes even when the energy condition is violated, that is, for $(\\rho+3p)<0$. This result may be useful in the investigation of the possible clustering of dark energy. All the examples dealt with have apparent horizons which form before the formation of the singularity. The singularities formed are shell focusing in nature. The density of the scalar field distribution is seen to diverge at singularity. The Ricci scalar also diverges at the singularity. The interior spherically symmetric metric is matched with exterior Vaidya metric at the hypersurface and the appropriate junction conditions are obtained.

Koyel Ganguly; Narayan Banerjee

2012-10-03T23:59:59.000Z

94

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

for plasma boundary control [D. A. Gates, etal., submitted to Nuclear Fusion (2005)]. More recently Physics Laboratory Status of the Control System on the National Spherical Torus Experiment (NSTX) D://www.ntis.gov/ordering.htm #12;Status of the Control System on the National Spherical Torus Experiment (NSTX) D. A. Gatesa , J. R

95

PREPARED FORTHE U.S. DEPARTMENT ENERGY, UNDER CONTRACT DEAC0276CH03073  

E-Print Network [OSTI]

Modes during Neutral Beam Heating the National Spherical Torus Experiment by E.D. Fredrickson Plasma Physics Laboratory Publications Reports FiscaL Year 2002. home page PPPL Reports Publications http://www.ntis.gov/ordering.htm #12; Observation Beam Driven Modes during Neutral Beam Heating National Spherical Torus Experiment E

96

E-Print Network 3.0 - advanced bumpy torus Sample Search Results  

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

Mathematics Page: << < 1 2 3 4 5 > >> Page: << < 1 2 3 4 5 > >> 21 GENERICITY OF GEODESIC FLOWS WITH POSITIVE TOPOLOGICAL ENTROPY ON S2 Summary: ) and the two-torus (Klein...

97

Ideal magnetohydrodynamic equilibrium in a non-symmetric topological torus  

SciTech Connect (OSTI)

An alternative representation of an ideal magnetohydrodynamic equilibrium is developed. The representation is a variation of one given by A. Salat, Phys. Plasmas 2, 1652 (1995). The system of equations is used to study the possibility of non-symmetric equilibria in a topological torus, here an approximate rectangular parallelopiped, with periodicity in two of the three rectangular coordinates. An expansion is carried out in the deviation of pressure surfaces from planes. Resonances are manifest in the process. Nonetheless, provided the magnetic shear is small, it is shown that it is possible to select the magnetic fields and flux surfaces in such a manner that no singularities appear on resonant surfaces. One boundary surface of the parallelopiped is not arbitrary but is dependent on the equilibrium in question. A comparison of the solution sets of axisymmetric and non-axisymmetric equilibria suggests that the latter have a wider class of possible boundary shapes but more restrictive rotational transform profiles. No proof of convergence of the series is given.

Weitzner, Harold [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)

2014-02-15T23:59:59.000Z

98

Electron Bernstein Wave Experiment on the Madison Symmetric Torus  

SciTech Connect (OSTI)

A system to heat electrons and possibly drive off-axis field-aligned current is under development on the Madison Symmetric Torus RFP. Staged experiments have reached an input power of 150 kW at 3.6G Hz and have produced a localized increase in SXR emission during rf injection. This measured emission is consistent with modeling in its location, energy spectrum and dependence on radial diffusion within the plasma. The emission is strongest in the region where ray tracing predicts deposition of the injected power. The multi-chord SXR camera used is sensitive to 4-7 keV photons. Enhanced emission in this energy range is consistent with Fokker-Plank modeling of EBW injection. The enhanced SXR emission vanishes quickly when radial diffusion in the plasma is high (as indicated by m = 0 magnetic activity); this is also consistent with Fokker-Plank modeling. An increase of boron emission (and presumably boron within the plasma) is also observed during EBW injection. This presents an alternative explanation to the enhanced SXR emission. Subsequent experiments with a different antenna at 100 kW input showed a small increase in SXR emission near 3 keV. A higher frequency experiment (5.5 GHz) with more input power available is currently under construction. Initial tests are centered on a circular waveguide launcher which requires only a 5 cm circular port in the vacuum vessel and has a target launch power of 400 kW.

Anderson, J. K.; Burke, D. R.; Forest, C. B.; Goetz, J. A.; Kaufman, M. C.; Seltzman, A. H. [Department of Physics, University of Wisconsin, Madison WI 53706 (United States)

2009-11-26T23:59:59.000Z

99

A component test facility based on the spherical tokamak  

SciTech Connect (OSTI)

Recent experiments (Synakowski et al 2004 Nucl. Fusion 43 1648, Lloyd et al 2004 Plasma Phys. Control. Fusion 46 13477) on the Spherical Tokamak (or Spherical Torus, ST) (Peng 2000 Phys. Plasmas 7 1681) have discovered robust plasma conditions, easing shaping, stability limits, energy confinement, self-driven current and sustainment. This progress has encouraged an update of the plasma conditions and engineering of a Component Test Facility (CTF), (Cheng 1998 Fusion Eng. Des. 38 219) which is a very valuable step in the development of practical fusion energy. The testing conditions in a CTF are characterized by high fusion neutron fluxes Gamma(n) approximate to 8.8 x 10(13) n s(-1) cm(-2) ('wall loading' W-L approximate to 2 MW m(-2)), over size-scale > 10(5) cm(2) and depth-scale > 50 cm, delivering > 3 accumulated displacement per atom per year ('neutron fluence' > 0.3 MW yr(-1) m(-2)) (Abdou et al 1999 Fusion Technol. 29 1). Such conditions are estimated to be achievable in a CTF with R-0 = 1.2 m, A = 1.5, elongation similar to 3, I-p similar to 12 MA, B-T similar to 2.5 T, producing a driven fusion burn using 47 MW of combined neutral beam and RF heating power. A design concept that allows straight-line access via remote handling to all activated fusion core components is developed and presented. The ST CTF will test the lifetime of single-turn, copper alloy centre leg for the toroidal field coil without an induction solenoid and neutron shielding and require physics data on solenoid-free plasma current initiation, ramp-up to and sustainment at multiple megaampere level. A systems code that combines the key required plasma and engineering science conditions of CTF has been prepared and utilized as part of this study. The results show high potential for a family of relatively low cost CTF devices to suit a range of fusion engineering and technology test missions.

Peng, Yueng Kay Martin [ORNL; Fogarty, P. J. [Oak Ridge National Laboratory (ORNL); Burgess, Thomas W [ORNL; Strickler, Dennis J [ORNL; Nelson, Brad E [ORNL; Tsai, C. C. [Oak Ridge National Laboratory (ORNL)

2005-01-01T23:59:59.000Z

100

Three-point spherical mirror mount  

DOE Patents [OSTI]

A three-point spherical mirror mount for use with lasers is disclosed. The improved mirror mount is adapted to provide a pivot ring having an outer surface with at least three spaced apart mating points to engage an inner spherical surface of a support housing.

Cutburth, R.W.

1984-01-23T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Localized waves with spherical harmonic symmetries  

E-Print Network [OSTI]

We introduce a class of propagation invariant spatiotemporal optical wave packets with spherical harmonic symmetries in their field configurations. The evolution of these light orbitals is considered theoretically in ...

Mills, M. S.

102

Method for making spherical binderless pellets  

DOE Patents [OSTI]

A method for making spherical binderless pellets using a rotating drum mixer whereby at least a portion of the particles comprising the pellets is comprised of coking coal particles.

Grubbs, Donald K. (Rector, PA); Kochanowski, Andrew T. (Spring Church, PA)

1983-01-01T23:59:59.000Z

103

Sphericity determination using resonant ultrasound spectroscopy  

DOE Patents [OSTI]

A method is provided for grading production quantities of spherical objects, such as roller balls for bearings. A resonant ultrasound spectrum (RUS) is generated for each spherical object and a set of degenerate sphere-resonance frequencies is identified. From the degenerate sphere-resonance frequencies and known relationships between degenerate sphere-resonance frequencies and Poisson's ratio, a Poisson's ratio can be determined, along with a 'best' spherical diameter, to form spherical parameters for the sphere. From the RUS, fine-structure resonant frequency spectra are identified for each degenerate sphere-resonance frequency previously selected. From each fine-structure spectrum and associated sphere parameter values an asphericity value is determined. The asphericity value can then be compared with predetermined values to provide a measure for accepting or rejecting the sphere. 14 figs.

Dixon, R.D.; Migliori, A.; Visscher, W.M.

1994-10-18T23:59:59.000Z

104

Preliminary Physics Motivation and Engineering Design Assessment of the National High Power Torus  

SciTech Connect (OSTI)

In April 2006, Dr. Ray Orbach, Director of the DOE Office of Science, challenged the fusion community to "propose a new facility... which will put the U.S. at the lead in world fusion science." Analysis of the gaps between expected ITER performance and the requirements of a demonstration power plant (Demo) pointed to the critical and urgent need to develop fusion-relvant plasma-material interface (PMI) solutions consistent with sustained high plasma performance. A survey of world fusion program indicated that present and planned experimental devices do not advance the PMI issue beyond ITER, and a major dedicated experimental facility is warranted. Such a facility should provide the flexibility and access needed to solve plasma boundary challenges related to divertor heat flux and particle exhaust while also developing methods to minimize hydrogenic isotope retention and remaining compatible with high plasma performance.

Robert D. Woolley

2009-06-11T23:59:59.000Z

105

Local well-posedness for the Zakharov system on multidimensional torus  

E-Print Network [OSTI]

The initial value problem of the Zakharov system on two dimensional torus with general period is shown to be locally well-posed in the Sobolev spaces of optimal regularity, including the energy space. Proof relies on a standard iteration argument using the Bourgain norms. The same strategy is also applicable to three and higher dimensional cases.

Kishimoto, Nobu

2011-01-01T23:59:59.000Z

106

THE CLASSIFICATION OF DEHN FILLINGS ON THE OUTER TORUS OF A 1-BRIDGE BRAID  

E-Print Network [OSTI]

SOLID TORI Ying-Qing Wu1 Abstract. Let K = K(w, b, t) be a 1-bridge braid in a solid torus V , and let #DMS 0203394 1 #12;2 YING-QING WU Figure 1.1 Let be a (p, q) curve on T with respect to the standard

Wu, Ying-Qing

107

DEPLETED MAGNETIC FLUX TUBES AS PROBES OF THE IO TORUS PLASMA  

E-Print Network [OSTI]

and Astronomy, University of Iowa, Iowa City, IA 52242, USA ABSTRACT On the initial pass by Io the Galileo that they were depleted in their energy content. These tubes have not been seen on every return to the Io torus balance with neighboring flux tubes in steady state. Figure 1 shows such pressure balance. The magnitude

Russell, Christopher T.

108

Spherical Harmonic Decomposition on a Cubic Grid  

E-Print Network [OSTI]

A method is described by which a function defined on a cubic grid (as from a finite difference solution of a partial differential equation) can be resolved into spherical harmonic components at some fixed radius. This has applications to the treatment of boundary conditions imposed at radii larger than the size of the grid, following Abrahams, Rezzola, Rupright et al.(gr-qc/9709082}. In the method described here, the interpolation of the grid data to the integration 2-sphere is combined in the same step as the integrations to extract the spherical harmonic amplitudes, which become sums over grid points. Coordinates adapted to the integration sphere are not needed.

Charles W. Misner

1999-10-12T23:59:59.000Z

109

Existence of exotic torus configuration in high-spin excited states of $^{40}$Ca  

E-Print Network [OSTI]

We investigate the possibility of the existence of the exotic torus configuration in the high-spin excited states of $^{40}$Ca. We here consider the spin alignments about the symmetry axis. To this end, we use a three-dimensional cranked Skyrme Hartree-Fock method and search for stable single-particle configurations. We find one stable state with the torus configuration at the total angular momentum $J=$ 60 $\\hbar$ and an excitation energy of about 170 MeV in all calculations using various Skyrme interactions. The total angular momentum J=60 $\\hbar$ consists of aligned 12 nucleons with the orbital angular momenta $\\Lambda=+4$, +5, and +6 for spin up-down neutrons and protons. The obtained results strongly suggest that a macroscopic amount of circulating current breaking the time-reversal symmetry emerges in the high-spin excited state of $^{40}$Ca.

T. Ichikawa; J. A. Maruhn; N. Itagaki; K. Matsuyanagi; P. -G. Reinhard; S. Ohkubo

2012-07-26T23:59:59.000Z

110

Traces of holomorphic families of operators on the noncommutative torus and on Hilbert modules  

E-Print Network [OSTI]

We revisit traces of holomorphic families of pseudodifferential operators on a closed manifold in view of geometric applications. We then transpose the corresponding analytic constructions to two different geometric frameworks; the noncommutative torus and Hilbert modules. These traces are meromorphic functions whose residues at the poles as well as the constant term of the Laurent expansion at zero (the latter when the family at zero is a differential operator) can be expressed in terms of Wodzicki residues and extended Wodzicki residues involving logarithmic operators. They are therefore local and contain geometric information. For holomorphic families leading to zeta regularised traces, they relate to the heat-kernel asymptotic coefficients via an inverse Mellin mapping theorem. We revisit Atiyah's L^2-index theorem by means of the (extended) Wodzicki residue and interpret the scalar curvature on the noncommutative two torus as an (extended) Wodzicki residue.

Sara Azzali; Cyril Lvy; Carolina Neira Jimnez; Sylvie Paycha

2015-01-26T23:59:59.000Z

111

Water adsorption on aggregates of spherical aerosol nano particles  

E-Print Network [OSTI]

graphite planer substrate; the result corresponds well with previous simulation work. Adsorption of both noble gas and water onto a single spherical nano particle and aggregates of spherical nano particles has been computed with the developed equation...

Nie, Chu

2005-11-01T23:59:59.000Z

112

The Torus Universe in the Polygon Approach to 2+1-Dimensional Gravity  

E-Print Network [OSTI]

In this paper we describe the matter-free toroidal spacetime in 't Hooft's polygon approach to 2+1-dimensional gravity (i.e. we consider the case without any particles present). Contrary to earlier results in the literature we find that it is not possible to describe the torus by just one polygon but we need at least two polygons. We also show that the constraint algebra of the polygons closes.

M. Welling

1996-06-06T23:59:59.000Z

113

Mach reflection of spherical detonation waves  

SciTech Connect (OSTI)

When two detonation waves collide, the shape of the wave front at their intersection can be used to categorize the flow as regular or irregular reflection. In the case of regular reflection, the intersection of the waves forms a cusp. In the case of irregular reflection, the cusp is replaced by a leading shock locus that bridges the incident waves. Many workers have studied irregular or Mach reflection of detonation waves, but most of the their experimental work has focused on the interaction of plane detonation waves. Reflection of spherical detonation waves has received less attention. This study also differs from previous work in that the focus is to measure the relationship between the detonation velocity and the local wave curvatue for irregular reflection of spherical detonation waves. Two explosives with different detonation properties, PBX 9501 and PBX 9502, are compared.

Hull, L.M.

1993-07-01T23:59:59.000Z

114

Generalized harmonic formulation in spherical symmetry  

E-Print Network [OSTI]

In this pedagogically structured article, we describe a generalized harmonic formulation of the Einstein equations in spherical symmetry which is regular at the origin. The generalized harmonic approach has attracted significant attention in numerical relativity over the past few years, especially as applied to the problem of binary inspiral and merger. A key issue when using the technique is the choice of the gauge source functions, and recent work has provided several prescriptions for gauge drivers designed to evolve these functions in a controlled way. We numerically investigate the parameter spaces of some of these drivers in the context of fully non-linear collapse of a real, massless scalar field, and determine nearly optimal parameter settings for specific situations. Surprisingly, we find that many of the drivers that perform well in 3+1 calculations that use Cartesian coordinates, are considerably less effective in spherical symmetry, where some of them are, in fact, unstable.

Evgeny Sorkin; Matthew W. Choptuik

2010-04-30T23:59:59.000Z

115

An Engineering Evaluation of Spherical Resorcinol Formaldehyde Resin  

SciTech Connect (OSTI)

A small column ion exchange (SCIX) system has been proposed for removal of cesium from caustic, supernatant, and dissolved salt solutions stored or generated from high-level tank wastes at the US Department of Energy (DOE) Hanford Site and Savannah River Sites. In both instances, deployment of SCIX systems, either in-tank or near-tank, is a means of expediting waste pretreatment and dispositioning with minimal or no new infrastructure requirements. Conceptually, the treatment approach can utilize a range of ion exchange media. Previously, both crystalline silicotitanate (CST), an inorganic, nonelutable sorbent, and resorcinol-formaldehyde (RF), an organic, elutable resin, have been considered for cesium removal from tank waste. More recently, Pacific Northwest National Laboratory (PNNL) evaluated use of SuperLig{reg_sign} 644, an elutable ion exchange medium, for the subject application. Results of testing indicate hydraulic limitations of the SuperLig{reg_sign} resin, specifically a high pressure drop through packed ion exchange columns. This limitation is likely the result of swelling and shrinkage of the irregularly shaped (granular) resin during repeated conversions between sodium and hydrogen forms as the resin is first loaded then eluted. It is anticipated that a similar flow limitation would exist in columns packed with conventional, granular RF resin. However, use of spherical RF resin is a likely means of mitigating processing limitations due to excessive pressure drop. Although size changes occur as the spherical resin is cycled through loading and elution operations, the geometry of the resin is expected to effectively mitigate the close packing that leads to high pressure drops across ion exchange columns. Multiple evaluations have been performed to determine the feasibility of using spherical RF resin and to obtain data necessary for design of an SCIX process. The work performed consisted of examination of radiation effects on resin performance, quantification of cesium adsorption performance as a function of operating temperature and pH, and evaluation of sodium uptake (titration) as function of pH and counteranion concentration. The results of these efforts are presented in this report. Hydraulic performance of the resin and the use of eluant alternatives to nitric acid have also been evaluated and have been reported elsewhere (Taylor 2009, Taylor and Johnson 2009).

Birdwell Jr, Joseph F [ORNL; Lee, Denise L [ORNL; Taylor, Paul Allen [ORNL; Collins, Robert T [ORNL; Hunt, Rodney Dale [ORNL

2010-09-01T23:59:59.000Z

116

NSTX Upgrade Project Execution Plan NSTX Upgrade Project  

E-Print Network [OSTI]

NSTX Upgrade Project Execution Plan NSTX Upgrade Project Project Execution Plan National Spherical Torus Experiment (NSTX) Upgrade Project Execution Plan Revision 1 October 6, 2011 Submitted by: R. Strykowsky NSTX Upgrade Project Manager _____________________________ M. Williams Associate Director, PPPL

Princeton Plasma Physics Laboratory

117

NSTX Upgrade Project Execution Plan NSTX Upgrade Project  

E-Print Network [OSTI]

NSTX Upgrade Project Execution Plan NSTX Upgrade Project Project Execution Plan National Spherical Torus Experiment (NSTX) Upgrade Project Execution Plan Revision 3 October 12, 2012 Administrative Change Submitted by: ______________________________ R. Strykowsky NSTX Upgrade Project Manager Anthony Indelicato

Princeton Plasma Physics Laboratory

118

Spherical gravitating condensers in general relativity  

SciTech Connect (OSTI)

By a spherical gravitating condenser we mean two concentric charged shells made of perfect fluids restricted by the condition that the electric field is nonvanishing only between the shells. Flat space is assumed inside the inner shell. By using Israel's formalism we first analyze the general system of N shells and then concentrate on the two-shell condensers. Energy conditions are taken into account; physically interesting cases are summarized in two tables, but also more exotic situations in which, for example, the inner shell may occur below the inner horizon of the corresponding Reissner-Nordstroem geometry or the spacetime is curved only inside the condenser are considered. Classical limits are mentioned.

Bicak, J.; Guerlebeck, N. [Institute of Theoretical Physics, Charles University, V Holesovickach 2, 180 00 Praha 8-Holesovice (Czech Republic); Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muehlenberg 1, D-14476 Golm (Germany)

2010-05-15T23:59:59.000Z

119

Casimir Energy of a Spherical Shell  

E-Print Network [OSTI]

The Casimir energy for a conducting spherical shell of radius $a$ is computed using a direct mode summation approach. An essential ingredient is the implementation of a recently proposed method based on Cauchy's theorem for an evaluation of the eigenfrequencies of the system. It is shown, however, that this earlier calculation uses an improper set of modes to describe the waves exterior to the sphere. Upon making the necessary corrections and taking care to ensure that no mathematically ill-defined expressions occur, the technique is shown to leave numerical results unaltered while avoiding a longstanding criticism raised against earlier calculations of the Casimir energy.

M. E. Bowers; C. R. Hagen

1998-06-23T23:59:59.000Z

120

Capillary condensation for fluids in spherical cavities  

E-Print Network [OSTI]

The capillary condensation for fluids into spherical nano-cavities is analyzed within the frame of two theoretical approaches. One description is based on a widely used simplified version of the droplet model formulated for studying atomic nuclei. The other, is a more elaborated calculation performed by applying a density functional theory. The agreement between both models is examined and it is shown that a small correction to the simple fluid model improves the predictions. A connection to results previously obtained for planar slits and cylindrical pores is done.

Ignacio Urrutia; Leszek Szybisz

2006-02-03T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Soret Motion of a Charged Spherical Colloid  

E-Print Network [OSTI]

The thermophoretic motion of a charged spherical colloidal particle and its accompanying cloud of counterions and co-ions in a temperature gradient is studied theoretically. Using the Debye-Huckel approximation, the Soret drift velocity of a weakly charged colloid is calculated analytically. For highly charged colloids, the nonlinear system of electrokinetic equations is solved numerically, and the effects of high surface potential, dielectrophoresis, and convection are examined. Our results are in good agreement with some of the recent experiments on highly charged colloids without using adjustable parameters.

Seyyed Nader Rasuli; Ramin Golestanian

2008-08-05T23:59:59.000Z

122

Vacuum fluctuations for spherical gravitational impulsive waves  

E-Print Network [OSTI]

We propose a method for calculating vacuum fluctuations on the background of a spherical impulsive gravitational wave which results in a finite expression for the vacuum expectation value of the stress-energy tensor. The method is based on first including a cosmological constant as an auxiliary constant. We show that the result for the vacuum expectation value of the stress-energy tensor in second-order perturbation theory is finite if both the cosmological constant and the infrared parameter tend to zero at the same rate.

M. Hortasu

1998-04-30T23:59:59.000Z

123

Initial Results from the Lost Alpha Diagnostics on Joint European Torus  

SciTech Connect (OSTI)

Two devices have been installed in the Joint European Torus (JET) vacuum vessel near the plasma boundary to investigate the loss of energetic ions and fusion products in general and alpha particles in particular during the upcoming JET experiments. These devices are (i) a set of multichannel thin foil Faraday collectors, and (ii) a well collimated scintillator which is optically connected to a charge-coupled device. Initial results, including the radial energy and poloidal dependence of lost ions from hydrogen and deuterium plasmas during the 200506 JET restart campaign, will be presented.

Darrow, Doug; Cecil, Ed; Ellis, Bob; Fullard, Keith; Hill, Ken; Horton, Alan; Kiptily, Vasily; Pedrick, Les; Reich, Matthias

2007-07-25T23:59:59.000Z

124

Topological Invariants and Ground-State Wave Functions of Topological Insulators on a Torus  

E-Print Network [OSTI]

We define topological invariants in terms of the ground states wave functions on a torus. This approach leads to precisely defined formulas for the Hall conductance in four dimensions and the topological magneto-electric $\\theta$ term in three dimensions, and their generalizations in higher dimensions. They are valid in the presence of arbitrary many-body interaction and disorder. These topological invariants systematically generalize the two-dimensional Niu-Thouless-Wu formula, and will be useful in numerical calculations of disordered topological insulators and strongly correlated topological insulators, especially fractional topological insulators.

Zhong Wang; Shou-Cheng Zhang

2014-01-25T23:59:59.000Z

125

Simulations of LH coupling in the Madison Symmetric Torus Reversed Field Pinch  

SciTech Connect (OSTI)

Simulations using several codes are being performed in support of the LH experiment in the Madison Symmetric Torus (MST) Reversed Field Pinch (RFP). Due to the special requirements of the MST RFP configuration (tight-fitting conducting shell in which only minimal portholes can be tolerated), a novel interdigital line slow-wave launch structure is used, mounted below the mid plane on the inboard side. The unusual configuration made it necessary to modify the main RF coupling code, RANT3D/AORSA1D-H, which was primarily developed for tokamak simulations. Preliminary results will be presented.

Carlsson, J.; Smithe, D. [Tech-X Corporation, Boulder USA (United States); Cartert, M. [Oak Ridge National Laboratory, Oak Ridge (United States); Burke, D.; Kaufman, M.; Goetz, J. [University of Wisconsin, Madison (United States)

2007-09-28T23:59:59.000Z

126

Simulations of lower-hybrid coupling in the Madison Symmetric Torus  

SciTech Connect (OSTI)

Simulations of Lower Hybrid (LH) coupling in the Madison Symmetric Torus (MST) Reversed Field Pinch (RFP) will be presented. Due to the special requirements of the RFP configuration (tight-fitting conducting shell in which only minimal portholes are acceptable), an unusual interdigital line slow-wave antenna is used, mounted below the mid plane on the inboard side. A number of codes are used, including VORPAL, RANT3D/AORSA1D-H and MWS, each solving different equations and using different algorithms. Output from the different codes will be presented and compared to verify the simulation results.

Carlsson, Johan; Smithe, David [Tech-X Corporation, Boulder, Colorado (United States); Carter, Mark [Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States); Kaufman, Mike [University of Wisconsin, Madison, Wisconsin (United States)

2009-11-26T23:59:59.000Z

127

A spherical joint piston design for high speed diesel engines  

SciTech Connect (OSTI)

A spherical joint piston and connecting rod have been developed through design proof-of-concept. The spherical joint allows piston rotation. The benefits of a rotating, symmetrical piston are: mechanical and thermal load symmetry, improved ring sealing and lubrication, and reduced bearing loads, scuffing, clearances and oil consumption. The assembly includes a squeeze cast, fiber reinforced aluminum spherical joint piston. Reinforcement is located in the piston bowl and skirt. The connecting rod consists of a spherical small end positioned on an elliptical cross-sectioned shank blended into a conventional big end. The assembly has operated at cylinder pressures exceeding of 24 MPa.

Wiczynski, P.D. [Cummins Engine Co., Inc., Columbus, IN (United States); Mielke, S. [Kolbenschmidt AG, Neckarsulm (Germany); Conrow, R.

1996-09-01T23:59:59.000Z

128

All spherically symmetric charged anisotropic solutions for compact star  

E-Print Network [OSTI]

In the present paper we develop an algorithm for all spherically symmetric anisotropic charged fluid distribution. Considering a new source function $\

Maurya, S K; Ray, Saibal

2015-01-01T23:59:59.000Z

129

All spherically symmetric charged anisotropic solutions for compact star  

E-Print Network [OSTI]

In the present paper we develop an algorithm for all spherically symmetric anisotropic charged fluid distribution. Considering a new source function $\

S. K. Maurya; Y. K. Gupta; Saibal Ray

2015-02-05T23:59:59.000Z

130

TORUS: Theory of Reactions for Unstable iSotopes - Year 1 Continuation and Progress Report  

SciTech Connect (OSTI)

The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding started on June 1, 2010, it will have been running for nine months by the date of submission of this Annual Continuation and Progress Report on March 1, 2011. The extent of funding was reduced from the original application, and now supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.

Arbanas, G; Elster, C; Escher, J; Mukhamedzhanov, A; Nunes, F; Thompson, I J

2011-02-24T23:59:59.000Z

131

Conformal perturbation theory and higher spin entanglement entropy on the torus  

E-Print Network [OSTI]

We study the free fermion theory in 1+1 dimensions deformed by chemical potentials for holomorphic, conserved currents at finite temperature and on a spatial circle. For a spin-three chemical potential \\mu, the deformation is related at high temperatures to a higher spin black hole in hs[0] theory on AdS_3 spacetime. We calculate the order \\mu^2 corrections to the single interval Renyi and entanglement entropies on the torus using the bosonized formulation. A consistent result, satisfying all checks, emerges upon carefully accounting for both perturbative and winding mode contributions in the bosonized language. The order \\mu^2 corrections involve integrals that are finite but potentially sensitive to contact term singularities. We propose and apply a prescription for defining such integrals which matches the Hamiltonian picture and passes several non-trivial checks for both thermal corrections and the Renyi entropies at this order. The thermal corrections are given by a weight six quasi-modular form, whilst the Renyi entropies are controlled by quasi-elliptic functions of the interval length with modular weight six. We also point out the well known connection between the perturbative expansion of the partition function in powers of the spin-three chemical potential and the Gross-Taylor genus expansion of large-N Yang-Mills theory on the torus. We note the absence of winding mode contributions in this connection, which suggests qualitatively different entanglement entropies for the two systems.

Shouvik Datta; Justin R. David; S. Prem Kumar

2014-12-12T23:59:59.000Z

132

Major Milestone: PPPL completes first quadrant of the heart of the National  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and InterfacesAdministration -Lowellfor 2013 |Spherical Torus Experiment

133

Torus instability  

E-Print Network [OSTI]

The expansion instability of a toroidal current ring in low-beta magnetized plasma is investigated. Qualitative agreement is obtained with experiments on spheromak expansion and with essential properties of solar coronal mass ejections, unifying the two apparently disparate classes of fast and slow coronal mass ejections.

B. Kliem; T. Toeroek

2006-08-04T23:59:59.000Z

134

Dynamical friction force exerted on spherical bodies  

E-Print Network [OSTI]

We present a rigorous calculation of the dynamical friction force exerted on a spherical massive perturber moving through an infinite homogenous system of field stars. By calculating the shape and mass of the polarization cloud induced by the perturber in the background system, which decelerates the motion of the perturber, we recover Chandrasekhar's drag force law with a modified Coulomb logarithm. As concrete examples we calculate the drag force exerted on a Plummer sphere or a sphere with the density distribution of a Hernquist profile. It is shown that the shape of the perturber affects only the exact form of the Coulomb logarithm. The latter converges on small scales, because encounters of the test and field stars with impact parameters less than the size of the massive perturber become inefficient. We confirm this way earlier results based on the impulse approximation of small angle scatterings.

O. Esquivel; B. Fuchs

2007-04-30T23:59:59.000Z

135

Static Solutions of Einstein's Equations with Spherical Symmetry  

E-Print Network [OSTI]

The Schwarzschild solution is a complete solution of Einstein's field equations for a static spherically symmetric field. The Einstein's field equations solutions appear in the literature, but in different ways corresponding to different definitions of the radial coordinate. We attempt to compare them to the solutions with nonvanishing energy density and pressure. We also calculate some special cases with changes in spherical symmetry.

Iftikhar Ahmad; Maqsoom Fatima; Najam-ul-Basat

2014-05-02T23:59:59.000Z

136

Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization via periodic orbits  

E-Print Network [OSTI]

Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization for the periodic orbits in a strongly coupled multidimen- sional Hamiltonian system, namely the hydrogen atom.15.Gy, 05.45.-a, 45.20.Jj I. INTRODUCTION The hydrogen atom in crossed electric and magnetic fields

137

Electron cyclotron emission radiometer upgrade on the Joint European Torus (JET) tokamak  

SciTech Connect (OSTI)

The capabilities of the Joint European Torus (JET) electron cyclotron emission (ECE) diagnostics have recently been extended with an upgrading of the heterodyne radiometer. The number of channels has been doubled to 96 channels, with a frequency separation corresponding to <1 cm for JET magnetic field gradient, and with a frequency response of 1 MHz. This enhancement has increased the radial coverage of the ECE electron temperature measurements in JET to approximately the full plasma column (limited at R>2.6 m for the X-mode due to harmonic overlap) at almost all magnetic field values used at JET (1.7 T

Luna, E. de la; Sanchez, J.; Tribaldos, V.; Conway, G.; Suttrop, W.; Fessey, J.; Prentice, R.; Gowers, C.; Chareau, J. M. [Asociacion EURATOM-CIEMAT para Fusion, CIEMAT, Madrid (Spain); IPP-EURATOM Association, Garching (Germany); EURATOM-UKAEA Fusion Associations, Culham Science Centre, Abingdon (United Kingdom); European Commission, Institute for Transuranium Elements, Karlsruhe (Germany)

2004-10-01T23:59:59.000Z

138

Statistical analysis of variations in impurity ion heating at reconnection events in the Madison Symmetric Torus  

SciTech Connect (OSTI)

The connection between impurity ion heating and other physical processes in the plasma is evaluated by studying variations in the amount of ion heating at reconnection events in the Madison Symmetric Torus (MST). Correlation of the change in ion temperature with individual tearing mode amplitudes indicates that the edge-resonant modes are better predictors for the amount of global ion heating than the core-resonant modes. There is also a strong correlation between ion heating and current profile relaxation. Simultaneous measurements of the ion temperature at different toroidal locations reveal, for the first time, a toroidal asymmetry to the ion heating in MST. These results present challenges for existing heating theories and suggest a stronger connection between edge-resonant tearing modes, current profile relaxation, and ion heating than has been previously thought.

Cartolano, M. S.; Craig, D., E-mail: darren.craig@wheaton.edu [Wheaton College, Wheaton, Illinois 60187 (United States); Den Hartog, D. J.; Kumar, S. T. A.; Nornberg, M. D. [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States) [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, Madison, Wisconsin 53706 (United States)

2014-01-15T23:59:59.000Z

139

Group-Theoretical Quantization of 2+1 Geavity in the Metric-Torus Sector  

E-Print Network [OSTI]

A symmetry based quantization method of reparametrization invariant systems is described; it will work for all systems that possess complete sets of perennials whose Lie algebras close and which generate a sufficiently large symmetry groups. The construction leads to a quantum theory including a Hilbert space, a complete system of operator observables and a unitary time evolution. The method is applied to the 2+1 gravity. The paper is restricted to the metric-torus sector, zero cosmological constant $\\Lambda$ and it makes strong use of the so-called homogeneous gauge; the chosen algebra of perennials is that due to Martin. Two frequent problems are tackled. First, the Lie algebra of perennials does not generate a group of symmetries. The notion of group completion of a reparametrization invariant system is introduced so that the group does act; the group completion of the physical phase space of our model is shown to add only some limit points to it so that the ranges of observables are not unduly changed. Second, a relatively large number of relations between observables exists; they are transferred to the quantum theory by the well-known methods due to Kostant and Kirillov. In this way, a uniqueness of the physical representation of some extension of Martin's algebra is shown. The Hamiltonian is defined by a systematic procedure due to Dirac; for the torus sector, the result coincides with that by Moncrief. The construction may be extensible to higher genera and non-zero $\\Lambda$ of the 2+1 gravity, because some complete sets of perennials are well-known and there are no obstructions to the closure of the algebra.

P. Hajicek

1997-05-29T23:59:59.000Z

140

Nonlinear elastic analysis of arbitrarily loaded shells of revolution by the matrix displacement method  

E-Print Network [OSTI]

Meridional Stress Along Arc Length for Spherical Cap-Torus-Cylinder Configuration (Radius to Thickness Ratio of Torus = 10) Circumferential Stress Along Are Length toz Spherical Cap-Torus-Cylinder Configuration (Radius to Thickness Ratio of Torus = 10...) 9-3. Meridional Stress Along Arc Length for Spherical Cap-Torus-Cylinder Configuration (Radius to Thickness Ratio of Torus = 20) 9-6. Circumferential Stress Along Arc Length for Spherical Cap-Torus-Cylinder Configuration (Radius to Thickness...

Haisler, Walter E

1968-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Spherically symmetric inhomogeneous model with Chaplygin gas  

E-Print Network [OSTI]

We investigate the late time acceleration with a Chaplygin type of gas in spherically symmetric inhomogeneous model. At the early phase we get Einstien-deSitter type of solution generalised to inhomogeneous spacetime. But at late stage of the evolution our solutions admit the accelerating nature of the universe. For a large scale factor our model behaves like a ?CDM model. We calculate the deceleration parameter for this anisotropic model, which, unlike its homogeneous counterpart, shows that the flip is not syn- chronous occurring early at the outer shells. This is in line with other physical processes in any inhomogeneous models. Depending upon initial conditions our solution also gives bouncing universe. In the absence of inhomogeneity our solution reduces to wellknown solutions in homogeneous case. We have also calculated the effective deceleration parameter in terms of Hubble parameter. The whole situation is later discussed with the help of wellknown Raychaudhury equation and the results are compared with the previous case. This work is an extension of our recent communication where an attempt was made to see if the presence of extra dimensions and/or inhomogeneity can trigger an inflation in a matter dominated Lemaitre Tolman Bondi model.

D. Panigrahi; S. Chatterjee

2011-08-11T23:59:59.000Z

142

Small spherical tokamaks for nuclear applications  

SciTech Connect (OSTI)

Recent experimental tests have produced encouraging data concerning plasma properties in the spherical tokamak (ST), a tokamak configuration with the aspect ratio (R{sub 0}/a) significantly below two. Here R{sub 0} and a are the major and minor radii, respectively. Large gains in plasma performance and external field utilization are projected as R{sub 0}/a is reduced from the normal range (2.5 and higher) to 1.5 or less. This introduces the possibility for small, D-T fueled, driven, steady-state ST devices capable of producing a fusion neutron wall loading in the range of 0.5 to 2.0 MW/m{sup 2}. The cases with neutron wall loads in the range of 1 to 2 MW/m{sup 2} could serve as the fusion volume neutron source for testing full-function nuclear blankets of significant sizes (about 1 m by 1 m facing the plasma). Those in the range of 0.5 to 1 MW/m{sup 2} could serve as the fusion driver for transmutation of nuclear wastes. Important plasma physics, technology, and engineering issues in implementing such small fusion devices will be identified and discussed, together with the potential contributions by this line of research to reducing time and cost of fusion energy development.

Peng, Y.K. M. [Oak Ridge National Lab, TN (United States); Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)] [and others

1994-12-31T23:59:59.000Z

143

PUBLISHED VERSION Fusion alpha-particle diagnostics for DT experiments on the Joint European Torus  

E-Print Network [OSTI]

Association Euratom -MEdC, National Institute for Laser, Plasma and Radiation Physics, Romania f Max

144

Spherical cloaking using nonlinear transformations for improved segmentation into concentric isotropic coatings  

E-Print Network [OSTI]

Two novel classes of spherical invisibility cloaks based on nonlinear transformation have been studied. The cloaking characteristics are presented by segmenting the nonlinear transformation based spherical cloak into ...

Hu, Li

145

E-Print Network 3.0 - advanced non-spherical particle Sample...  

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

results for: advanced non-spherical particle Page: << < 1 2 3 4 5 > >> 1 Droplet Microfluidics for Fabrication of Non-Spherical Particles Summary: Droplet Microfluidics for...

146

ElasticPlastic Spherical Contact Modeling Including Roughness Effects  

E-Print Network [OSTI]

A multilevel model for elasticplastic contact between ajunction growth of an elasticplastic spherical contact. J.nite element based elasticplastic model for the contact of

Li, L.; Etsion, I.; Talke, F. E.

2010-01-01T23:59:59.000Z

147

Spherically Symmetric Considerations for a Higher Order Theory of Gravitation  

E-Print Network [OSTI]

A higher order theory of gravitation is considered which is obtained by modifying Einstein field equations. The Lagrange used to modify this in the form a polynomial in (scalar curvature) R. In this equation we have studied spherical symmetric metric.

S. N. Pandey; B. K. Sinha

2009-11-03T23:59:59.000Z

148

Matter Collineations of Some Static Spherically Symmetric Spacetimes  

E-Print Network [OSTI]

We derive matter collineations for some static spherically symmetric spacetimes and compare the results with Killing, Ricci and Curvature symmetries. We conclude that matter and Ricci collineations are not, in general, the same.

M. Sharif

2004-01-16T23:59:59.000Z

149

Performance characterization of the Caltech corn act torus injector P. K. Loewenhardt,a) M. R. Browqb) J. Yee, and P. M. Bellan  

E-Print Network [OSTI]

A compact torus (CT), or spheromak, is a toroidal mag- netofluid configuration in which plasma is cot tokamak by the Caltech Spheromak Ijec- tion experiment to study helicity injection and refueling,3

Brown, Michael R.

150

Free energy and complexity of spherical bipartite models  

E-Print Network [OSTI]

We investigate both free energy and complexity of the spherical bipartite spin glass model. We first prove a variational formula in high temperature for the limiting free energy based on the well-known Crisanti-Sommers representation of the mixed p-spin spherical model. Next, we show that the mean number of local minima at low levels of energy is exponentially large in the size of the system and we derive a bound on the location of the ground state energy.

Antonio Auffinger; Wei-Kuo Chen

2014-05-09T23:59:59.000Z

151

Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization via periodic orbits  

E-Print Network [OSTI]

A hierarchical ordering is demonstrated for the periodic orbits in a strongly coupled multidimensional Hamiltonian system, namely the hydrogen atom in crossed electric and magnetic fields. It mirrors the hierarchy of broken resonant tori and thereby allows one to characterize the periodic orbits by a set of winding numbers. With this knowledge, we construct the action variables as functions of the frequency ratios and carry out a semiclassical torus quantization. The semiclassical energy levels thus obtained agree well with exact quantum calculations.

Stephan Gekle; Jrg Main; Thomas Bartsch; T. Uzer

2006-10-02T23:59:59.000Z

152

An axisymmetric hydrodynamical model for the torus wind in AGN. II: X-ray excited funnel flow  

E-Print Network [OSTI]

We have calculated a series of models of outflows from the obscuring torus in active galactic nuclei (AGN). Our modeling assumes that the inner face of a rotationally supported torus is illuminated and heated by the intense X-rays from the inner accretion disk and black hole. As a result of such heating a strong biconical outflow is observed in our simulations. We calculate 3-dimensional hydrodynamical models, assuming axial symmetry, and including the effects of X-ray heating, ionization, and radiation pressure. We discuss the behavior of a large family of these models, their velocity fields, mass fluxes and temperature, as functions of the torus properties and X-ray flux. Synthetic warm absorber spectra are calculated, assuming pure absorption, for sample models at various inclination angles and observing times. We show that these models have mass fluxes and flow speeds which are comparable to those which have been inferred from observations of Seyfert 1 warm absorbers, and that they can produce rich absorption line spectra.

A. Dorodnitsyn; T. Kallman; D. Proga

2008-06-23T23:59:59.000Z

153

An axisymmetric hydrodynamical model for the torus wind in AGN. II: X-ray excited funnel flow  

E-Print Network [OSTI]

We have calculated a series of models of outflows from the obscuring torus in active galactic nuclei (AGN). Our modeling assumes that the inner face of a rotationally supported torus is illuminated and heated by the intense X-rays from the inner accretion disk and black hole. As a result of such heating a strong biconical outflow is observed in our simulations. We calculate 3-dimensional hydrodynamical models, assuming axial symmetry, and including the effects of X-ray heating, ionization, and radiation pressure. We discuss the behavior of a large family of these models, their velocity fields, mass fluxes and temperature, as functions of the torus properties and X-ray flux. Synthetic warm absorber spectra are calculated, assuming pure absorption, for sample models at various inclination angles and observing times. We show that these models have mass fluxes and flow speeds which are comparable to those which have been inferred from observations of Seyfert 1 warm absorbers, and that they can produce rich absorp...

Dorodnitsyn, A; Proga, D

2008-01-01T23:59:59.000Z

154

ACCRETION AND OUTFLOW FROM A MAGNETIZED, NEUTRINO COOLED TORUS AROUND THE GAMMA-RAY BURST CENTRAL ENGINE  

SciTech Connect (OSTI)

We calculate the structure and short-term evolution of a gamma-ray burst (GRB) central engine in the form of a turbulent torus accreting onto a stellar mass black hole. Our models apply to the short GRB events, in which a remnant torus forms after the neutron star-black hole or a double neutron star merger and is subsequently accreted. We study the two-dimensional, relativistic models and concentrate on the effects of the black hole and flow parameters as well as the neutrino cooling. We compare the resulting structure and neutrino emission to the results of our previous one-dimensional simulations. We find that the neutrino cooled torus launches a powerful mass outflow, which contributes to the total neutrino luminosity and mass loss from the system. The neutrino luminosity may exceed the Blandford-Znajek luminosity of the polar jets and the subsequent annihilation of neutrino-antineutrino pairs will provide an additional source of power to the GRB emission.

Janiuk, Agnieszka; Mioduszewski, Patryk [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Moscibrodzka, Monika, E-mail: agnes@cft.edu.pl [Department of Physics, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, NV 89154 (United States)

2013-10-20T23:59:59.000Z

155

Calibration of an advanced neutral particle analyzer for the Madison Symmetric Torus reversed-field pinch  

SciTech Connect (OSTI)

A new E Parallel-To B neutral particle analyzer, which has recently been installed on Madison Symmetric Torus (MST) reversed-field pinch (RFP), has now been calibrated, allowing the measurement of the fast ion density and energy distribution. This diagnostic, dubbed the advanced neutral particle analyzer (ANPA), can simultaneously produce time resolved measurements of the efflux of both hydrogen and deuterium ions from the plasma over a 35 keV energy range with an energy resolution of 2-4 keV and a time resolution of 10 {mu}s. These capabilities are needed to measure both majority ion heating that occurs during magnetic reconnection events in MST and the behavior of the fast ions from the 1 MW hydrogen neutral beam injector on MST. Calibration of the ANPA was performed using a custom ion source that resides in the flight tube between the MST and the ANPA. In this work, the ANPA will be described, the calibration procedure and results will be discussed, and initial measurements of the time evolution of 25 keV neutral beam injection-born fast ions will be presented.

Reusch, J. A.; Anderson, J. K.; Eilerman, S. [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Belykh, V.; Polosatkin, S. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk (Russian Federation); Liu, D. [University of California-Irvine, Irvine, California 92697 (United States); Fiksel, G. [University of Rochester, Rochester, New York 14623 (United States)

2012-10-15T23:59:59.000Z

156

Plasma behaviour at high beta and high density in the Madison Symmetric Torus RFP  

SciTech Connect (OSTI)

Pellet fuelling of improved confinement Madison Symmetric Torus (MST) plasmas has resulted in high density and high plasma beta. The density in improved confinement discharges has been increased fourfold, and a record plasma beta (beta(tot) = 26%) for the improved confinement reversed-field pinch (RFP) has been achieved. At higher beta, a new regime for instabilities is accessed in which local interchange and global tearing instabilities are calculated to be linearly unstable, but experimentally, no severe effect, e. g., a disruption, is observed. The tearing instability, normally driven by the current gradient, is driven by the pressure gradient in this case, and there are indications of increased energy transport ( as compared with low-density improved confinement). Pellet fuelling is also compared with enhanced edge fuelling of standard confinement RFP discharges for the purpose of searching for a density limit in MST. In standard-confinement discharges, pellet fuelling peaks the density profile where edge fuelling cannot, but transport appears unchanged. For a limited range of plasma current, MST discharges with edge fuelling are constrained to a maximum density corresponding to the Greenwald limit. This limit is surpassed in pellet-fuelled improved confinement discharges.

Wyman, M. [University of Wisconsin, Madison; Chapman, B. E. [University of Wisconsin, Madison; Ahn, J. W. [University of Wisconsin, Madison; Almagri, A. F. [University of Wisconsin, Madison; Anderson, J. [University of Wisconsin, Madison; Bonomo, F. [Consorzio RFX, Italy; Bower, D L [University of California, Los Angeles; Combs, Stephen Kirk [ORNL; Craig, D. [University of Wisconsin, Madison; Foust, Charles R [ORNL

2009-01-01T23:59:59.000Z

157

Interplay between MacDonald and Hall-Littlewood expansions of extended torus superpolynomials  

E-Print Network [OSTI]

In arXiv:1106.4305 extended superpolynomials were introduced for the torus links T[m,mk+r], which are functions on the entire space of time variables and, at expense of reducing the topological invariance, possess additional algebraic properties, resembling those of the matrix model partition functions and the KP/Toda tau-functions. Not surprisingly, being a suitable extension it actually allows one to calculate the superpolynomials. These functions are defined as expansions into MacDonald polynomials, and their dependence on k is entirely captured by the action of the cut-and-join operator, like in the HOMFLY case. We suggest a simple description of the coefficients in these character expansions, by expanding the initial (at k=0) conditions for the k-evolution into the new auxiliary basis, this time provided by the Hall-Littlewood polynomials, which, hence, play a role in the description of the dual m-evolution. For illustration we list manifest expressions for a few first series, mk\\pm 1, mk\\pm 2, mk\\pm 3, mk\\pm 4. Actually all formulas were explicitly tested up to m=17 strands in the braid.

A. Mironov; A. Morozov; Sh. Shakirov; A. Sleptsov

2012-02-17T23:59:59.000Z

158

Smoother than a circle, or How non commutative geometry provides the torus with an egocentred metric  

E-Print Network [OSTI]

We give an overview on the metric aspect of noncommutative geometry, especially the metric interpretation of gauge fields via the process of "fluctuation of the metric". Connes' distance formula associates to a gauge field on a bundle P equipped with a connection H a metric. When the holonomy is trivial, this distance coincides with the horizontal distance defined by the connection. When the holonomy is non trivial, the noncommutative distance has rather surprising properties. Specifically we exhibit an elementary example on a 2-torus in which the noncommutative metric d is somehow more interesting than the horizontal one since d preserves the S^1-structure of the fiber and also guarantees the smoothness of the length function at the cut-locus. In this sense the fiber appears as an object "smoother than a circle". As a consequence, from a intrinsic metric point of view developed here, any observer whatever his position on the fiber can equally pretend to be "the center of the world".

Pierre Martinetti

2006-09-25T23:59:59.000Z

159

CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect (OSTI)

This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two {approx}11 mL beds in columns in a lead-lag arrangement. The first two campaigns used Savannah River Site (SRS) Tank 2F nonradioactive simulant while the latter two were fed with actual dissolved salt in the Savannah River National Laboratory (SRNL) Shielded Cells. Both radioactive cycles ran to cesium breakthrough of the lead column. The resin beds saw in excess of 400 bed volumes of feed in each cycle. Resin disposal plans in tank farm processing depend on characterizations of resin used with actual tank feed. Following a final 30 bed volume (BV) elution with nitric acid, the resin beds were found to contain detectable chromium, barium, boron, aluminum, iron, sodium, sulfur, plutonium, cesium, and mercury. Resin affinity for plutonium is important in criticality safety considerations. Cesium-137 was found to be less than 10E+7 dpm/g of resin, similar to past work with sRF resin. Sulfur levels are reasonably consistent with other work and are expected to represent sulfur chemistry used in the resin manufacture. There were low but detectable levels of technetium, americium, and curium. Toxicity Characteristic Leaching Procedure (TCLP) work on the used (eluted) resin samples showed significant contents of mercury, barium, and chromium. One resin sample exceeded the TCLP level for mercury while the other metals were below TCLP levels. TCLP organics measurements indicated measurable benzene in one case, though the source was unknown. Results of this work were compared with other work on similar sRF resin characterizations in this report. This is the first work to quantify mercury on sRF resin. Resin mercury content is important in plans for the disposition of used sRF resin. Mercury speciation in high level waste (HLW) is unknown. It may be partly organic, one example being methyl mercury cation. Further study of the resin's affinity for mercury is recommended.

Nash, C.; Duignan, M.

2010-02-23T23:59:59.000Z

160

Method to produce large, uniform hollow spherical shells  

DOE Patents [OSTI]

The invention is a method to produce large uniform hollow spherical shells by (1) forming uniform size drops of heat decomposable or vaporizable material, (2) evaporating the drops to form dried particles, (3) coating the dried particles with a layer of shell forming material and (4) heating the composite particles to melt the outer layer and to decompose or vaporize the inner particle to form an expanding inner gas bubble. The expanding gas bubble forms the molten outer layer into a shell of relatively large diameter. By cycling the temperature and pressure on the molten shell, nonuniformities in wall thickness can be reduced. The method of the invention is utilized to produce large uniform spherical shells, in the millimeter to centimeter diameter size range, from a variety of materials and of high quality, including sphericity, concentricity and surface smoothness, for use as laser fusion or other inertial confinement fusion targets as well as other applications.

Hendricks, C.D.

1983-09-26T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Plastic instabilities in statically and dynamically loaded spherical vessels  

SciTech Connect (OSTI)

Significant changes were made in design limits for pressurized vessels in the 2007 version of the ASME Code (Section VIII, Div. 3) and 2008 and 2009 Addenda. There is now a local damage-mechanics based strain-exhaustion limit as well as the well-known global plastic collapse limit. Moreover, Code Case 2564 (Section VIII, Div. 3) has recently been approved to address impulsively loaded vessels. It is the purpose of this paper to investigate the plastic collapse limit as it applies to dynamically loaded spherical vessels. Plastic instabilities that could potentially develop in spherical shells under symmetric loading conditions are examined for a variety of plastic constitutive relations. First, a literature survey of both static and dynamic instabilities associated with spherical shells is presented. Then, a general plastic instability condition for spherical shells subjected to displacement controlled and impulsive loading is given. This instability condition is evaluated for six plastic and visco-plastic constitutive relations. The role of strain-rate sensitivity on the instability point is investigated. Calculations for statically and dynamically loaded spherical shells are presented, illustrating the formation of instabilities as well as the role of imperfections. Conclusions of this work are that there are two fundamental types of instabilities associated with failure of spherical shells. In the case of impulsively loaded vessels, where the pulse duration is short compared to the fundamental period of the structure, one instability type is found not to occur in the absence of static internal pressure. Moreover, it is found that the specific role of strain-rate sensitivity on the instability strain depends on the form of the constitutive relation assumed.

Duffey, Thomas A [Los Alamos National Laboratory; Rodriguez, Edward A [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

162

Dynamic slip velocity correlation using non-spherical particles  

E-Print Network [OSTI]

Mid-Point Weight, grams FIG. 10 - MEASURED AND FTITED MEANS FOR SPHERICITY DETERMINATION 0. 8 S P h e r 0. 6 1 t 7 t 0 0. 4 M a t o h 02 0 0. 2 0. 4 0. 6 0. 8 1 1. 2 1. 4 Mid-Point Weight, grams FIG. 11 - CALCULATED SPHERICITIES... RECOMMENDATIONS NOMENCLATURE REFERENCES APPENDIX A . 1 2 6 11 13 15 15 25 31 31 36 42 43 45 47 APPENDIX B . Page 57 113 LIST OF FIGURES FIGURE 1: DRAG COEFFICIENT VS. PARTICLE REYNOLDS NUMBER FOR VARIOUS SHAPED PARTICLES FIGURE 2...

Pecore, Douglas Wilkin

1990-01-01T23:59:59.000Z

163

Spherical cloaking using multilayer shells of ordinary dielectrics  

SciTech Connect (OSTI)

An approach for spherical cloaking using multilayer ordinary dielectric materials has been developed. The total scattering cross section (TSCS) of the spherical multilayer shell with metallic core was derived based on the Mie theory. The dielectric profile of the shell was optimized to minimize the TSCS of the cloaked target. The specific directions, at which the scattering could be practically eliminated, were detected. The influence of the target size and the dielectric material loss on the cloaking efficiency was analyzed. It was shown that the cloaking efficiency for larger targets could be improved by employing lossy materials in the shell.

Wang, Xiaohui; Chen, Fang; Semouchkina, Elena, E-mail: esemouch@mtu.edu [Department of Electrical and Computer Engineering, Michigan Technological University, Houghton, MI, 49931 (United States)] [Department of Electrical and Computer Engineering, Michigan Technological University, Houghton, MI, 49931 (United States)

2013-11-15T23:59:59.000Z

164

The spherical collapse model in time varying vacuum cosmologies  

E-Print Network [OSTI]

We investigate the virialization of cosmic structures in the framework of flat FLRW cosmological models, in which the vacuum energy density evolves with time. In particular, our analysis focuses on the study of spherical matter perturbations, as they decouple from the background expansion, "turn around" and finally collapse. We generalize the spherical collapse model in the case when the vacuum energy is a running function of the Hubble rate, $\\Lambda=\\Lambda(H)$. A particularly well motivated model of this type is the so-called quantum field vacuum, in which $\\Lambda(H)$ is a quadratic function, $\\Lambda(H)=n_0+n_2\\,H^2$, with $n_0\

S. Basilakos; M. Plionis; J. Sola

2010-09-22T23:59:59.000Z

165

Frequency domain photothermal radiometry with spherical solids Chinhua Wanga  

E-Print Network [OSTI]

of incident beam spot size and thermal diffusion length within the modulation fre- quency range of interest the thermal diffusivity of cylindrical rods and tubes was evaluated using the flash method. Salazar et al.9 both theoretical and experimental photothermal radiometry studies on spherical geometries and thermal

Mandelis, Andreas

166

The SPECTRUM of the CURL OPERATOR SPHERICALLY SYMMETRIC DOMAINS  

E-Print Network [OSTI]

-minimizers are the axially symmetric spheromak fields found by Woltjer and Chandrasekhar-Kendall, and on spherical shells they are spheromak-like fields. The geometry and topology of these minimum-energy fields, as well as of some higher · 52.55.Fa Tokamaks · 52.55.Hc Stellerators, spheromaks, etc. · 95.30.Qd Astrophysics: MHD and plasmas

DeTurck, Dennis

167

No Scalar Hair Theorem for a Charged Spherical Black Hole  

E-Print Network [OSTI]

This paper consolidates noscalar hair theorem for a charged spherically symmetric black hole in four dimension in general relativity as well as in all scalar tensor theories, both minimally and nonminimally coupled, when the effective Newtonian constant of gravity is positive. However, there is an exception when the matter field itself is coupled to the scalar field, such as in dilaton gravity.

N. Banerjee; S. Sen

1998-08-11T23:59:59.000Z

168

Collapse of non-spherically symmetric scalar field distributions  

E-Print Network [OSTI]

In the present work the collapse scenario of some exact non-spherical models with a minimally coupled scalar field is studied. Scalar field collapse with planar as well as toroidal, cylindrical and pseudoplanar symmetries have been investigated. It is shown that the scalar field may have collapsing modes even if it has the equation of state corresponding to that of a dark energy.

Koyel Ganguly; Narayan Banerjee

2011-05-23T23:59:59.000Z

169

Casimir energy of a spherical shell in $?-$Minkowski spacetime  

E-Print Network [OSTI]

We study the Casimir energy of a spherical shell of radius $a$ in $\\kappa$-Minkowski spacetime for a complex field with an asymmetric ordering and obtain the energy up to $O(1/\\kappa^2)$. We show that the vacuum breaks particle and anti-particle symmetry if one requires the spectra to be consistent with the blackbody radiation at the commutative limit.

Hyeong-Chan Kim; Chaiho Rim; Jae Hyung Yee

2008-12-12T23:59:59.000Z

170

The Einstein-Vlasov-Maxwell(EVM) System with Spherical Symmetry  

E-Print Network [OSTI]

We look for the global in time solution of the Cauchy problem corresponding to the asymptotically flat spherically symmetric EVM system with small initial data. Using an estimate, we also prove that if solution of the system stated above develops a singularity at all time, then the first one has to appear at the center of symmetry.

P. Noundjeu

2005-05-23T23:59:59.000Z

171

Continuing Development of Models Based on Spherical Geodesic Grids  

E-Print Network [OSTI]

Continuing Development of Models Based on Spherical Geodesic Grids Ross Heikes, Joon-Hee Jung, C to finite-difference operators 3) Some numerical results from an aqua-planet simulation #12;Part1: Geodesic -- array based The geodesic grid can be mapped to a set of square arrays. 1 3 4 5 6 7 8 9 10 11 12 13 14 15

Collett Jr., Jeffrey L.

172

Anvil effect in spherical indentation testing on sheet metal  

E-Print Network [OSTI]

A spherical indentation test is considered to be invalid if there is presence of a visible mark on the side of the sheet metal facing the anvil and exactly below the indentation. With the available standard loads of the conventional testers...

Dhaigude, Mayuresh Mukund

2009-06-02T23:59:59.000Z

173

The Dirac equation in D-dimensional spherically symmetric spacetimes  

E-Print Network [OSTI]

We expound in detail a method frequently used to reduce the Dirac equation in D-dimensional (D >= 4) spherically symmetric spacetimes to a pair of coupled partial differential equations in two variables. As a simple application of these results we exactly calculate the quasinormal frequencies of the uncharged Dirac field propagating in the D-dimensional Nariai spacetime.

A. Lopez-Ortega

2009-06-15T23:59:59.000Z

174

Decay Rates for Spherical Scalar Waves in the Schwarzschild Geometry  

E-Print Network [OSTI]

The Cauchy problem is considered for the scalar wave equation in the Schwarzschild geometry. Using an integral spectral representation we derive the exact decay rate for solutions of the Cauchy problem with spherical symmetric initial data, which is smooth and compactly supported outside the event horizon.

Johann Kronthaler

2007-09-24T23:59:59.000Z

175

Shell Crossing Singularities in Quasi-Spherical Szekeres Models  

E-Print Network [OSTI]

We investigate the occurrence of shell crossing singularities in quasi-spherical Szekeres dust models with or without a cosmological constant. We study the conditions for shell crossing singularity both from physical and geometrical point of view and they are in agreement.

Subenoy Chakraborty; Ujjal Debnath

2007-12-16T23:59:59.000Z

176

ABAREX: A neutron spherical optical-statistical model code  

SciTech Connect (OSTI)

The spherical optical-statistical model is briefly reviewed and the capabilities of the neutron scattering code, ABAREX, are presented. Input files for ten examples, in which neutrons are scattered by various nuclei, are given and the output of each run is discussed in detail.

Lawson, R.D.

1992-06-01T23:59:59.000Z

177

Dynamics of multiple double layers in high pressure glow discharge in a simple torus  

SciTech Connect (OSTI)

Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presence of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.

Kumar Paul, Manash, E-mail: manashkr@gmail.com [Department of Physics, National Institute of Technology Agartala, Tripura799 046 (India); Sharma, P. K.; Thakur, A.; Kulkarni, S. V.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat382 428 (India)

2014-06-15T23:59:59.000Z

178

Embedding global barrier and collective in torus network with each node combining input from receivers according to class map for output to senders  

DOE Patents [OSTI]

Embodiments of the invention provide a method, system and computer program product for embedding a global barrier and global interrupt network in a parallel computer system organized as a torus network. The computer system includes a multitude of nodes. In one embodiment, the method comprises taking inputs from a set of receivers of the nodes, dividing the inputs from the receivers into a plurality of classes, combining the inputs of each of the classes to obtain a result, and sending said result to a set of senders of the nodes. Embodiments of the invention provide a method, system and computer program product for embedding a collective network in a parallel computer system organized as a torus network. In one embodiment, the method comprises adding to a torus network a central collective logic to route messages among at least a group of nodes in a tree structure.

Chen, Dong; Coteus, Paul W; Eisley, Noel A; Gara, Alan; Heidelberger, Philip; Senger, Robert M; Salapura, Valentina; Steinmacher-Burow, Burkhard; Sugawara, Yutaka; Takken, Todd E

2013-08-27T23:59:59.000Z

179

Analysis, Design, and Operation of a Spherical Inverted-F Antenna  

E-Print Network [OSTI]

This thesis presents the analysis, design, and fabrication of a spherical inverted-F antenna (SIFA). The SIFA consists of a spherically conformal rectangular patch antenna recessed into a quarter section of a metallic sphere. The sphere acts as a...

McDonald, Jacob J.

2010-07-14T23:59:59.000Z

180

Efficient 3D shape matching and retrieval using a concrete radialized spherical projection representation  

E-Print Network [OSTI]

Efficient 3D shape matching and retrieval using a concrete radialized spherical projection We present a 3D shape retrieval methodology based on the theory of spherical harmonics. Using PCA on the face normals of the model. The 3D model is decomposed into a set of spherical functions

Paris-Sud XI, Université de

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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
to obtain the most current and comprehensive results.


181

Observation of a Reflected Shock in an Indirectly Driven Spherical Implosion at the National Ignition Facility  

E-Print Network [OSTI]

, New Mexico 87545, USA 4 Laboratory for Laser Energetics, University of Rochester, 250 East River Road-ray ablation to transfer energy to a much thicker capsule rather than direct laser isochoric heating of a very of the following points: (i) An initially near vacuum Au hohlraum can sustain a very efficient x-ray drive [6

182

Gravitational and electric energies in collapse of spherically thin capacitor  

E-Print Network [OSTI]

In our previous article (PHYSICAL REVIEW D 86, 084004 (2012)), we present a study of strong oscillating electric fields and electron-positron pair-production in gravitational collapse of a neutral stellar core at or over nuclear densities. In order to understand the back-reaction of such electric energy building and radiating on collapse, we adopt a simplified model describing the collapse of a spherically thin capacitor to give an analytical description how gravitational energy is converted to both kinetic and electric energies in collapse. It is shown that (i) averaged kinetic and electric energies are the same order, about an half of gravitational energy of spherically thin capacitor in collapse; (ii) caused by radiating and rebuilding electric energy, gravitational collapse undergoes a sequence of "on and off" hopping steps in the microscopic Compton scale. Although such a collapse process is still continuous in terms of macroscopic scales, it is slowed down as kinetic energy is reduced and collapsing tim...

Ruffini, Remo

2013-01-01T23:59:59.000Z

183

Free falling and rising of spherical and angular particles  

SciTech Connect (OSTI)

Direct numerical simulations of freely falling and rising particles in an infinitely long domain, with periodic lateral boundary conditions, are performed. The focus is on characterizing the free motion of cubical and tetrahedral particles for different Reynolds numbers, as an extension to the well-studied behaviour of freely falling and rising spherical bodies. The vortical structure of the wake, dynamics of particle movement, and the interaction of the particle with its wake are studied. The results reveal mechanisms of path instabilities for angular particles, which are different from those for spherical ones. The rotation of the particle plays a more significant role in the transition to chaos for angular particles. Following a framework similar to that of Mougin and Magnaudet [Wake-induced forces and torques on a zigzagging/spiralling bubble, J. Fluid Mech. 567, 185194 (2006)], the balance of forces and torques acting on particles is discussed to gain more insight into the path instabilities of angular particles.

Rahmani, M., E-mail: mona.rahmani@ifpen.fr; Wachs, A., E-mail: anthony.wachs@ifpen.fr [Fluid Mechanics Department, IFP Energies nouvelles, Etablissement de Lyon, 69360 Solaize (France)

2014-08-15T23:59:59.000Z

184

Analyzing Correlation Functions with Tesseral and Cartesian Spherical Harmonics  

E-Print Network [OSTI]

The dependence of inter-particle correlations on the orientation of particle relative-momentum can yield unique information on the space-time features of emission in reactions with multiparticle final states. In the present paper, the benefits of a representation and analysis of the three-dimensional correlation information in terms of surface spherical harmonics is presented. The harmonics include the standard complex tesseral harmonics and the real cartesian harmonics. Mathematical properties of the lesser-known cartesian harmonics are illuminated. The physical content of different angular harmonic components in a correlation is described. The resolving power of different final-state effects with regarding to determining angular features of emission regions is investigated. The considered final-state effects include identity interference and strong and Coulomb interactions. The correlation analysis in terms of spherical harmonics is illustrated with the cases of gaussian and blast-wave sources for proton-charged meson and baryon-baryon pairs.

Pawel Danielewicz; Scott Pratt

2006-12-17T23:59:59.000Z

185

Analyzing Correlation Functions with Tesseral and Cartesian Spherical Harmonics  

E-Print Network [OSTI]

The dependence of inter-particle correlations on the orientation of particle relative-momentum can yield unique information on the space-time features of emission in reactions with multiparticle final states. In the present paper, the benefits of a representation and analysis of the three-dimensional correlation information in terms of surface spherical harmonics is presented. The harmonics include the standard complex tesseral harmonics and the real cartesian harmonics. Mathematical properties of the lesser-known cartesian harmonics are illuminated. The physical content of different angular harmonic components in a correlation is described. The resolving power of different final-state effects with regarding to determining angular features of emission regions is investigated. The considered final-state effects include identity interference and strong and Coulomb interactions. The correlation analysis in terms of spherical harmonics is illustrated with the cases of gaussian and blast-wave sources for proton-ch...

Danielewicz, P; Danielewicz, Pawel; Pratt, Scott

2006-01-01T23:59:59.000Z

186

Analyzing correlation functions with tesseral and Cartesian spherical harmonics  

SciTech Connect (OSTI)

The dependence of interparticle correlations on the orientation of particle relative momentum can yield unique information on the space-time features of emission in reactions with multiparticle final states. In the present paper, the benefits of a representation and analysis of the three-dimensional correlation information in terms of surface spherical harmonics is presented. The harmonics include the standard complex tesseral harmonics and the real Cartesian harmonics. Mathematical properties of the lesser known Cartesian harmonics are illuminated. The physical content of different angular harmonic components in a correlation is described. The resolving power of different final-state effects with regard to determining angular features of emission regions is investigated. The considered final-state effects include identity interference, strong interactions, and Coulomb interactions. The correlation analysis in terms of spherical harmonics is illustrated with the cases of Gaussian and blast-wave sources for proton-charged meson and baryon-baryon pairs.

Danielewicz, Pawel; Pratt, Scott [Department of Physics and Astronomy, and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

2007-03-15T23:59:59.000Z

187

TDHF fusion calculations for spherical+deformed systems  

E-Print Network [OSTI]

We outline a formalism to carry out TDHF calculations of fusion cross sections for spherical + deformed nuclei. The procedure incorporates the dynamic alignment of the deformed nucleus into the calculation of the fusion cross section. The alignment results from multiple E2/E4 Coulomb excitation of the ground state rotational band. Implications for TDHF fusion calculations are discussed. TDHF calculations are done in an unrestricted three-dimensional geometry using modern Skyrme force parametrizations.

A. S. Umar; V. E. Oberacker

2006-04-04T23:59:59.000Z

188

Spherical Resorcinol-Formaldehyde Synthesis by Inverse Suspension Polymerization  

SciTech Connect (OSTI)

Base catalyzed sol-gel polycondensation of resorcinol (1,3-dihydroxybenzene) with formaldehyde by inverse suspension polymerization leads to the formation of uniform, highly cross-linked, translucent, spherical gels, which have increased selectivity and capacity for cesium ion removal from high alkaline solutions. Because of its high selectivity for cesium ion, resorcinol-formaldehyde (R-F) resins are being considered for process scale column radioactive cesium removal by ion-exchange at the Waste Treatment and Immobilization Plant (WTP), which is now under construction at the Hanford site. Other specialty resins such as Superlig{reg_sign} 644 have been ground and sieved and column tested for process scale radioactive cesium removal but show high pressure drops across the resin bed during transition from column regeneration to loading and elution. Furthermore, van Deemter considerations indicate better displacement column chromatography by the use of spherical particle beads rather than irregularly shaped ground or granular particles. In our studies batch contact equilibrium experiments using a high alkaline simulant show a definite increase in cesium loading onto spherical R-F resin. Distribution coefficient (Kd) values ranged from 777 to 429 mL/g in the presence of 0.1M and 0.7M potassium ions, respectively. Though other techniques for making R-F resins have been employed, to our knowledge no one has made spherical R-F resins by inverse suspension polymerization. Moreover, in this study we discuss the data comparisons to known algebraic isotherms used to evaluate ion-exchange resins for WTP plant scale cesium removal operations.

Ray, Robert J.; Scrivens, Walter A.; Nash, Charles

2005-10-21T23:59:59.000Z

189

Energy of spherically symmetric spacetimes on regularizing teleparallelism  

E-Print Network [OSTI]

We calculate the total energy of an exact spherically symmetric solutions, i.e., Schwarzschild and Reissner Nordstr$\\ddot{o}$m, using the gravitational energy-momentum 3-form within the tetrad formulation of general relativity. We explain how the effect of the inertial makes the total energy unphysical! Therefore, we use the covariant teleparallel approach which makes the energy always physical one. We also show that the inertial has no effect on the calculation of momentum.

G. G. L. Nashed

2010-04-11T23:59:59.000Z

190

Global energy conservation in nonlinear spherical characteristic evolutions  

E-Print Network [OSTI]

Associated to the unique 4-parametric subgroup of translations, normal to the Bondi-Metzner-Sachs group, there exists a generator of the temporal translation asymptotic symmetry. Such a descriptor of the motion along the conformal orbit near null infinity is propagated to finite regions. This allows us to observe the global energy conservation even in extreme situations near the critical behavior of the massless scalar field collapse in spherical symmetry.

W. Barreto

2014-04-20T23:59:59.000Z

191

A New Result on the Dynamical Symmetry of Spherical Collapse  

E-Print Network [OSTI]

A dynamical symmetry for spherical collapse has been studied using a linear transformation of the initial data set (mass and kinetic energy function) and the area radius. With proper choice of the initial area radius, the evolution as well as the physical parameters namely energy density and shear remain invariant both initially and at any time instant. Finally, it is found that the final outcome of collapse depends on the initial choice of the area radius.

Subenoy Chakraborty; Asit Banerjee; Ujjal Debnath

2006-02-27T23:59:59.000Z

192

Self-similar spherical shock solution with sustained energy injection  

E-Print Network [OSTI]

We present the generalization of the Sedov-Taylor self-similar strong spherical shock solution for the case of a central energy source varying in time, $E=A t^k$, where $A$ and $k$ are constants. The known Sedov-Taylor solution corresponds to a particular adiabatic case of $k=0$ or \\emph{instant shock} with an instant energy source of the shock, $E=A$. The self-similar hydrodynamic flow in the nonadiabatic $k\

V. I. Dokuchaev

2002-09-20T23:59:59.000Z

193

Davis-Greenstein alignment of non-spherical grains  

E-Print Network [OSTI]

Paramagnetic alignment of non-spherical dust grains rotating at thermal velocities is studied. The analytical solution is found for the alignment measure of oblate grains. Perturbative approach is used for solving the problem. It is shown that even the first approximation of the suggested iteration procedure provides the accuracy well within one percent of the expected measure of alignment. The results obtained are applicable both to paramagnetic and to superferromagnetic grains.

A. Lazarian

1995-05-07T23:59:59.000Z

194

Global energy conservation in nonlinear spherical characteristic evolutions  

E-Print Network [OSTI]

Associated to the subgroup unique and four--parametric of translations, normal to the Bondi--Metzner--Sachs group, there exists a generator of the temporal translation asymptotic symmetry. {Such a descriptor of the motion along the conformal orbit near null infinity is propagated to finite regions. This allow us to observe the global energy conservation even in extreme situations near critical behavior of the massless scalar field collapse in spherical symmetry.

Barreto, W

2014-01-01T23:59:59.000Z

195

Stochastic control problems and spherical functions on symmetric spaces  

E-Print Network [OSTI]

situations (e.g. matrix groups and hyperbolic spaces). By using the additional structure available on symmetric spaces we are able to construct large families of explicitly solvable stochastic control problems in symmetric spaces of arbitrary rank. Received... by the editors October 26, 1992. 1991 Mathematics Subject Classification. Primary 93E20, 43A90; Secondary 58G32, 33C55, 53C35. Key words and phrases. Stochastic control, spherical functions, controlled diffusions in symmet- ric spaces, Laplace-Beltrami operator...

Duncan, Tyrone E.; Upmeier, H.

1995-01-01T23:59:59.000Z

196

Spherically Symmetric Solutions to Fourth-Order Theories of Gravity  

E-Print Network [OSTI]

Gravitational theories generated from Lagrangians of the form f(R) are considered. The spherically symmetric solutions to these equations are discussed, paying particular attention to features that differ from the standard Schwarzschild solution. The asymptotic form of solutions is described, as is the lack of validity of Birkhoff's theorem. Exact solutions are presented which illustrate these points and their stability and geodesics are investigated.

T. Clifton

2006-11-10T23:59:59.000Z

197

Method for preparing spherical ferrite beads and use thereof  

DOE Patents [OSTI]

The invention allows the fabrication of small, dense, highly polished spherical beads of hexagonal ferrites with selected compositions for use in nonreciprocal microwave and mm-wave devices as well as in microwave absorbent or reflective coatings, composites, and the like. A porous, generally spherical bead of hydrous iron oxide is made by a sol-gel process to form a substantially rigid bead having a generally fine crystallite size and correspondingly finely distributed internal porosity. The resulting gel bead is washed and hydrothermally reacted with a soluble alkaline earth salt (typically Ba or Sr) under conditions of elevated temperature and pressure to convert the bead into a mixed hydrous iron-alkaline earth oxide while retaining the generally spherical shape. This mixed oxide bead is then washed, dried, and calcined to produce the desired (BaFe.sub.12 O.sub.19 or SrFe.sub.12 O.sub.19) crystal structure. The calcined bead is then sintered to form a dense bead of the BaFe.sub.12 O.sub.19 and SrFe.sub.12 O.sub.19 phase suitable for polishing and incorporation into various microwave devices and components.

Lauf, Robert J. (Oak Ridge, TN); Anderson, Kimberly K. (Knoxville, TN); Montgomery, Frederick C. (Oak Ridge, TN); Collins, Jack L. (Knoxville, TN)

2002-01-01T23:59:59.000Z

198

Spherical codes, maximal local packing density, and the golden ratio  

E-Print Network [OSTI]

The densest local packing (DLP) problem in d-dimensional Euclidean space Rd involves the placement of N nonoverlapping spheres of unit diameter near an additional fixed unit-diameter sphere such that the greatest distance from the center of the fixed sphere to the centers of any of the N surrounding spheres is minimized. Solutions to the DLP problem are relevant to the realizability of pair correlation functions for packings of nonoverlapping spheres and might prove useful in improving upon the best known upper bounds on the maximum packing fraction of sphere packings in dimensions greater than three. The optimal spherical code problem in Rd involves the placement of the centers of N nonoverlapping spheres of unit diameter onto the surface of a sphere of radius R such that R is minimized. It is proved that in any dimension, all solutions between unity and the golden ratio to the optimal spherical code problem for N spheres are also solutions to the corresponding DLP problem. It follows that for any packing of nonoverlapping spheres of unit diameter, a spherical region of radius less than or equal to the golden ratio centered on an arbitrary sphere center cannot enclose a number of sphere centers greater than one more than the number that can be placed on the region's surface.

A. B. Hopkins; F. H. Stillinger; S. Torquato

2010-03-18T23:59:59.000Z

199

A Mass Bound for Spherically Symmetric Black Hole Spacetimes  

E-Print Network [OSTI]

Requiring that the matter fields are subject to the dominant energy condition, we establish the lower bound $(4\\pi)^{-1} \\kappa {\\cal A}$ for the total mass $M$ of a static, spherically symmetric black hole spacetime. (${\\cal A}$ and $\\kappa$ denote the area and the surface gravity of the horizon, respectively.) Together with the fact that the Komar integral provides a simple relation between $M - (4\\pi)^{-1} \\kappa A$ and the strong energy condition, this enables us to prove that the Schwarzschild metric represents the only static, spherically symmetric black hole solution of a selfgravitating matter model satisfying the dominant, but violating the strong energy condition for the timelike Killing field $K$ at every point, that is, $R(K,K) \\leq 0$. Applying this result to scalar fields, we recover the fact that the only black hole configuration of the spherically symmetric Einstein-Higgs model with arbitrary non-negative potential is the Schwarzschild spacetime with constant Higgs field. In the presence of electromagnetic fields, we also derive a stronger bound for the total mass, involving the electromagnetic potentials and charges. Again, this estimate provides a simple tool to prove a ``no-hair'' theorem for matter fields violating the strong energy condition.

M. Heusler

1994-11-21T23:59:59.000Z

200

Accurate evolutions of unequal-mass neutron-star binaries: properties of the torus and short GRB engines  

E-Print Network [OSTI]

We present new results from accurate and fully general-relativistic simulations of the coalescence of unmagnetized binary neutron stars with various mass ratios. The evolution of the stars is followed through the inspiral phase, the merger and prompt collapse to a black hole, up until the appearance of a thick accretion disk, which is studied as it enters and remains in a regime of quasi-steady accretion. Although a simple ideal-fluid equation of state with \\Gamma=2 is used, this work presents a systematic study within a fully general relativistic framework of the properties of the resulting black-hole--torus system produced by the merger of unequal-mass binaries. More specifically, we show that: (1) The mass of the torus increases considerably with the mass asymmetry and equal-mass binaries do not produce significant tori if they have a total baryonic mass M_tot >~ 3.7 M_sun; (2) Tori with masses M_tor ~ 0.2 M_sun are measured for binaries with M_tot ~ 3.4 M_sun and mass ratios q ~ 0.75-0.85; (3) The mass of the torus can be estimated by the simple expression M_tor(q, M_tot) = [c_1 (1-q) + c_2](M_max-M_tot), involving the maximum mass for the binaries and coefficients constrained from the simulations, and suggesting that the tori can have masses as large as M_tor ~ 0.35 M_sun for M_tot ~ 2.8 M_sun and q ~ 0.75-0.85; (4) Using a novel technique to analyze the evolution of the tori we find no evidence for the onset of non-axisymmetric instabilities and that very little, if any, of their mass is unbound; (5) Finally, for all the binaries considered we compute the complete gravitational waveforms and the recoils imparted to the black holes, discussing the prospects of detection of these sources for a number of present and future detectors.

Luciano Rezzolla; Luca Baiotti; Bruno Giacomazzo; David Link; Jose A. Font

2010-05-13T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Design of interferometer system for Keda Torus eXperiment using terahertz solid-state diode sources  

SciTech Connect (OSTI)

A solid-state source based terahertz (THz) interferometer diagnostic system has been designed and characterized for the Keda Torus eXperiment (KTX). The THz interferometer utilizes the planar diodes based frequency multiplier (X48) to provide the probing beam at fixed frequency 0.650 THz, and local oscillator is provided by an independent solid-state diode source with tunable frequency (0.650 THz +/? 10 MHz). Both solid-state sources have approximately 1 mW power. The planar-diode mixers optimized for high sensitivity, ?750 mV/mW, are used in the heterodyne detection system, which permits multichannel interferometer on KTX with a low phase noise. A sensitivity of {sub min} = 4.5 10{sup 16} m{sup ?2} and a temporal resolution of 0.2 ?s have been achieved during the initial bench test.

Xie, Jinlin, E-mail: jlxie@ustc.edu.cn; Wang, Haibo; Li, Hong; Lan, Tao; Liu, Adi; Liu, Wandong; Yu, Changxuan [School of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ding, Weixing [School of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); University of California-Los Angeles, P. O. Box 957099, Los Angeles, California 90095-7099 (United States)

2014-11-15T23:59:59.000Z

202

Global oscillations of a fluid torus as a modulation mechanism for black-hole high-frequency QPOs  

E-Print Network [OSTI]

We study strong-gravity effects on modulation of radiation emerging from accreting compact objects as a possible mechanism for flux modulation in QPOs. We construct a toy model of an oscillating torus in the slender approximation assuming thermal bremsstrahlung for the intrinsic emissivity of the medium and we compute observed (predicted) radiation signal including contribution of indirect (higher-order) images and caustics in the Schwarzschild spacetime. We show that the simplest oscillation mode in an accretion flow, axisymmetric up-and-down motion at the meridional epicyclic frequency, may be directly observable when it occurs in the inner parts of accretion flow around black holes. Together with the second oscillation mode, an in-and-out motion at the radial epicyclic frequency, it may then be responsible for the high-frequency modulations of the X-ray flux observed at two distinct frequencies (twin HF-QPOs) in micro-quasars.

Michal Bursa

2005-10-15T23:59:59.000Z

203

Full light absorption in single arrays of spherical nanoparticles  

E-Print Network [OSTI]

In this paper we show that arrays of core-shell nanoparticles function as effective thin absorbers of light. In contrast to known metamaterial absorbers, the introduced absorbers are formed by single planar arrays of spherical inclusions and enable full absorption of light incident on either or both sides of the array. We demonstrate possibilities for realizing different kinds of symmetric absorbers, including resonant, ultra-broadband, angularly selective, and all-angle absorbers. The physical principle behind these designs is explained considering balanced electric and magnetic responses of unit cells. Photovoltaic devices and thermal emitters are the two most important potential applications of the proposed designs.

Ra'di, Y; Kosulnikov, S U; Omelyanovich, M M; Morits, D; Osipov, A V; Simovski, C R; Tretyakov, S A

2015-01-01T23:59:59.000Z

204

Application of spherical diodes for megavoltage photon beams dosimetry  

SciTech Connect (OSTI)

Purpose: External beam radiation therapy (EBRT) usually uses heterogeneous dose distributions in a given volume. Designing detectors for quality control of these treatments is still a developing subject. The size of the detectors should be small to enhance spatial resolution and ensure low perturbation of the beam. A high uniformity in angular response is also a very important feature in a detector, because it has to measure radiation coming from all the directions of the space. It is also convenient that detectors are inexpensive and robust, especially to performin vivo measurements. The purpose of this work is to introduce a new detector for measuring megavoltage photon beams and to assess its performance to measure relative dose in EBRT. Methods: The detector studied in this work was designed as a spherical photodiode (1.8 mm in diameter). The change in response of the spherical diodes is measured regarding the angle of incidence, cumulated irradiation, and instantaneous dose rate (or dose per pulse). Additionally, total scatter factors for large and small fields (between 1 1 cm{sup 2} and 20 20 cm{sup 2}) are evaluated and compared with the results obtained from some commercially available ionization chambers and planar diodes. Additionally, the over-response to low energy scattered photons in large fields is investigated using a shielding layer. Results: The spherical diode studied in this work produces a high signal (150 nC/Gy for photons of nominal energy of 15 MV and 160 for 6 MV, after 12 kGy) and its angular dependence is lower than that of planar diodes: less than 5% between maximum and minimum in all directions, and 2% around one of the axis. It also has a moderated variation with accumulated dose (about 1.5%/kGy for 15 MV photons and 0.7%/kGy for 6 MV, after 12 kGy) and a low variation with dose per pulse (0.4%), and its behavior is similar to commercial diodes in total scatter factor measurements. Conclusions: The measurements of relative dose using the spherical diode described in this work show its feasibility for the dosimetry of megavoltage photon beams. A particularly important feature is its good angular response in the MV range. They would be good candidates forin vivo dosimetry, and quality assurance of VMAT and tomotherapy, and other modalities with beams irradiating from multiple orientations, such as Cyberknife and ViewRay, with minor modifications.

Barbs, Benigno, E-mail: bbarbes@unav.es [Servicio de Oncologa Radioterpica, Clnica Universidad de Navarra, Avda. Po XII, 36, E-31008 Pamplona, Navarra (Spain)] [Servicio de Oncologa Radioterpica, Clnica Universidad de Navarra, Avda. Po XII, 36, E-31008 Pamplona, Navarra (Spain); Azcona, Juan D. [Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Servicio de Oncologa Radioterpica, Clnica Universidad de Navarra, Avda. Po XII 36, E-31008 Pamplona, Navarra (Spain)] [Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Servicio de Oncologa Radioterpica, Clnica Universidad de Navarra, Avda. Po XII 36, E-31008 Pamplona, Navarra (Spain); Burguete, Javier [Departamento de Fsica y Matemtica Aplicada, Facultad de Ciencias, Universidad de Navarra, Irunlarrea 1, E-31008 Pamplona, Navarra (Spain)] [Departamento de Fsica y Matemtica Aplicada, Facultad de Ciencias, Universidad de Navarra, Irunlarrea 1, E-31008 Pamplona, Navarra (Spain); Mart-Climent, Josep M. [Servicio de Medicina Nuclear, Clnica Universidad de Navarra, Avda. Po XII 36, E-31008 Pamplona, Navarra (Spain)] [Servicio de Medicina Nuclear, Clnica Universidad de Navarra, Avda. Po XII 36, E-31008 Pamplona, Navarra (Spain)

2014-01-15T23:59:59.000Z

205

Numerical Analysis of Spherically Convergent Rayleigh-Taylor Experiments  

SciTech Connect (OSTI)

In the frame of a CEA/US DOE collaboration, radiation driven spherically convergent experiments were performed on the Nova laser in order m measure the Rayleigh-Taylor growth at the ablation front. Numerical simulations using the 2D Lagrangian code FCI2 have correctly reproduced experiments in moderate convergent geometry. [C. Cherfils et al., PRL 83, 5507 (1999)]. Experiments have addressed convergence ratios up to 4 by considering larger capsules, larger hohlraum and longer laser pulses [S.G. Glendinning et al., to be published in Physics of Plasmas]. Numerical analysis of these high convergence implosions is presented, and the effect of convergence on the Rayleigh-Taylor growth is investigated.

Galmiche, D.; Cherfils, C.; Glendinning, S.G.; Remington, B.A.; Richard, A.

2000-05-17T23:59:59.000Z

206

On the vacuum energy of a spherical plasma shell  

E-Print Network [OSTI]

We consider the vacuum energy of the electromagnetic field interacting with a spherical plasma shell together with a model for the classical motion of the shell. We calculate the heat kernel coefficients, especially that for the TM mode, and carry out the renormalization by redefining the parameters of the classical model. It turns out that this is possible and results in a model, which in the limit of the plasma shell becoming an ideal conductor reproduces the vacuum energy found by Boyer in 1968.

M. Bordag; N. Khusnutdinov

2008-01-14T23:59:59.000Z

207

Casimir energy for spherical shell in Schwarzchild black hole background  

E-Print Network [OSTI]

In this paper, we consider the Casimir energy of massless scalar field which satisfy Dirichlet boundary condition on a spherical shell. Outside the shell, the spacetime is assumed to be described by the Schwarzschild metric, while inside the shell it is taken to be the flat Minkowski space. Using zeta function regularization and heat kernel coefficients we isolate the divergent contributions of the Casimir energy inside and outside the shell, then using the renormalization procedure of the bag model the divergent parts are cancelled, finally obtaining a renormalized expression for the total Casimir energy.

M. R. Setare; M. B. Altaie

2003-08-28T23:59:59.000Z

208

Casimir interactions of an object inside a spherical metal shell  

E-Print Network [OSTI]

We investigate the electromagnetic Casimir interactions of an object contained within an otherwise empty, perfectly conducting spherical shell. For a small object we present analytical calculations of the force, which is directed away from the center of the cavity, and the torque, which tends to align the object opposite to the preferred alignment outside the cavity. For a perfectly conducting sphere as the interior object, we compute the corrections to the proximity force approximation (PFA) numerically. In both cases the results for the interior configuration match smoothly onto those for the corresponding exterior configuration.

Saad Zaheer; Sahand Jamal Rahi; Thorsten Emig; Robert L. Jaffe

2009-11-03T23:59:59.000Z

209

Spherical Thin-Shell Wormholes and Modified Chaplygin Gas  

E-Print Network [OSTI]

The purpose of this paper is to construct spherical thin-shell wormhole solutions through cut and paste technique and investigate the stability of these solutions in the vicinity of modified Chaplygin gas. The Darmois-Israel formalism is used to formulate the stresses of the surface concentrating the exotic matter. We explore the stability of the wormhole solutions by using the standard potential method. We conclude that there exist more stable as well as unstable solutions than the previous study with generalized Chaplygin gas \\cite{15}.

M. Sharif; M. Azam

2013-09-28T23:59:59.000Z

210

A non-conforming 3D spherical harmonic transport solver  

SciTech Connect (OSTI)

A new 3D transport solver for the time-independent Boltzmann transport equation has been developed. This solver is based on the second-order even-parity form of the transport equation. The angular discretization is performed through the expansion of the angular neutron flux in spherical harmonics (PN method). The novelty of this solver is the use of non-conforming finite elements for the spatial discretization. Such elements lead to a discontinuous flux approximation. This interface continuity requirement relaxation property is shared with mixed-dual formulations such as the ones based on Raviart-Thomas finite elements. Encouraging numerical results are presented. (authors)

Van Criekingen, S. [Commissariat a l'Energie Atomique CEA-Saclay, DEN/DM2S/SERMA/LENR Bat 470, 91191 Gif-sur-Yvette, Cedex (France)

2006-07-01T23:59:59.000Z

211

Rheotaxis of spherical active particles near a planar wall  

E-Print Network [OSTI]

For active particles the interplay between the self-generated hydrodynamic flow and an external shear flow, especially near bounding surfaces, can result in a rich behavior of the particles not easily foreseen from the consideration of the active and external driving mechanisms in isolation. For instance, under certain conditions, the particles exhibit "rheotaxis," i.e., they align their direction of motion with the plane of shear spanned by the direction of the flow and the normal of the bounding surface and move with or against the flow. To date, studies of rheotaxis have focused on elongated particles (e.g., spermatozoa), for which rheotaxis can be understood intuitively in terms of a "weather vane" mechanism. Here we investigate the possibility that spherical active particles, for which the "weather vane" mechanism is excluded due to the symmetry of the shape, may nevertheless exhibit rheotaxis. Combining analytical and numerical calculations, we show that, for a broad class of spherical active particles, rheotactic behavior may emerge via a mechanism which involves "self-trapping" near a hard wall owing to the active propulsion of the particles, combined with their rotation, alignment, and "locking" of the direction of motion into the shear plane. In this state, the particles move solely up- or downstream at a steady height and orientation.

W. E. Uspal; M. N. Popescu; S. Dietrich; M. Tasinkevych

2015-02-16T23:59:59.000Z

212

Spherically symmetric gravitating shell as a reparametrization invariant system  

E-Print Network [OSTI]

The subject of this paper are spherically symmetric thin shells made of barotropic ideal fluid and moving under the influence of their own gravitational field as well as that of a central black hole; the cosmological constant is assumed to be zero. The general super-Hamiltonian derived in a previous paper is rewritten for this spherically symmetric special case. The dependence of the resulting action on the gravitational variables is trivialized by a transformation due to Kucha\\v{r}. The resulting variational principle depends only on shell variables, is reparametrization invariant, and includes both first- and second-class constraints. Several equivalent forms of the constrained system are written down. Exclusion of the second-class constraints leads to a super-Hamiltonian which appears to overlap with that by Ansoldi et al. in a quarter of the phase space. As Kucha\\v{r}' variables are singular at the horizons of both Schwarzschild spacetimes inside and outside the shell, the dynamics is first well-defined only inside of 16 disjoint sectors. The 16 sectors are, however, shown to be contained in a single, connected symplectic manifold and the constraints are extended to this manifold by continuity. Poisson bracket between no two independent spacetime coordinates of the shell vanish at any intersection of two horizons.

P. Hajicek; Berne

1997-08-18T23:59:59.000Z

213

Electrostatic spherically symmetric configurations in gravitating nonlinear electrodynamics  

SciTech Connect (OSTI)

We perform a study of the gravitating electrostatic spherically symmetric (G-ESS) solutions of Einstein field equations minimally coupled to generalized nonlinear Abelian gauge models in three space dimensions. These models are defined by Lagrangian densities which are general functions of the gauge field invariants, restricted by some physical conditions of admissibility. They include the class of nonlinear electrodynamics supporting electrostatic spherically symmetric (ESS) nontopological soliton solutions in absence of gravity. We establish that the qualitative structure of the G-ESS solutions of admissible models is fully characterized by the asymptotic and central-field behaviors of their ESS solutions in flat space (or, equivalently, by the behavior of the Lagrangian densities in vacuum and on the point of the boundary of their domain of definition, where the second gauge invariant vanishes). The structure of these G-ESS configurations for admissible models supporting divergent-energy ESS solutions in flat space is qualitatively the same as in the Reissner-Nordstroem case. In contrast, the G-ESS configurations of the models supporting finite-energy ESS solutions in flat space exhibit new qualitative features, which are discussed in terms of the Arnowitt-Deser-Misner mass, the charge, and the soliton energy. Most of the results concerning well-known models, such as the electrodynamics of Maxwell, Born-Infeld, and the Euler-Heisenberg effective Lagrangian of QED, minimally coupled to gravitation, are shown to be corollaries of general statements of this analysis.

Diaz-Alonso, J.; Rubiera-Garcia, D. [LUTH, Observatoire de Paris, CNRS, , USAUniversite Paris Diderot, 5 Place Jules Janssen, 92190 Meudon (France) and Departamento de Fisica, Universidad de Oviedo, Avda. Calvo Sotelo 18, E-33007 Oviedo, Asturias (Spain)

2010-03-15T23:59:59.000Z

214

Numerical Relativity in Spherical Polar Coordinates: Off-center Simulations  

E-Print Network [OSTI]

We have recently presented a new approach for numerical relativity simulations in spherical polar coordinates, both for vacuum and for relativistic hydrodynamics. Our approach is based on a reference-metric formulation of the BSSN equations, a factoring of all tensor components, as well as a partially implicit Runge-Kutta method, and does not rely on a regularization of the equations, nor does it make any assumptions about the symmetry across the origin. In order to demonstrate this feature we present here several off-centered simulations, including simulations of single black holes and neutron stars whose center is placed away from the origin of the coordinate system, as well as the asymmetric head-on collision of two black holes. We also revisit our implementation of relativistic hydrodynamics and demonstrate that a reference-metric formulation of hydrodynamics together with a factoring of all tensor components avoids problems related to the coordinate singularities at the origin and on the axes. As a particularly demanding test we present results for a shock wave propagating through the origin of the spherical polar coordinate system.

Thomas W. Baumgarte; Pedro J. Montero; Ewald Mller

2015-01-21T23:59:59.000Z

215

A New Real-Time Method for Determining Particles Sphericity and...  

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

that are commonly either assumed or estimated from the measured mobility and vacuum aerodynamic diameters assuming again that the particles are spherical. Depending on the system,...

216

Application Of A Spherical-Radial Heat Transfer Model To Calculate...  

Open Energy Info (EERE)

Spherical-Radial Heat Transfer Model To Calculate Geothermal Gradients From Measurements In Deep Boreholes Jump to: navigation, search OpenEI Reference LibraryAdd to library...

217

SciTech Connect: Sphericity and symmetry breaking in the formation...  

Office of Scientific and Technical Information (OSTI)

and symmetry breaking in the formation of FrankKasper phases from one component materials Citation Details In-Document Search Title: Sphericity and symmetry breaking in the...

218

Electrostatic self-energy in static black holes with spherical symmetry  

E-Print Network [OSTI]

We determine the expression of the electrostatic self-energy for a point charge in the static black holes with spherical symmetry having suitable properties

B. Linet

2000-06-28T23:59:59.000Z

219

E-Print Network 3.0 - apple latent spherical Sample Search Results  

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

plastic deformation under the tip, two spherical diamond tips with radii of ... Source: Sun, Qing-Ping - Department of Mechanical Engineering, Hong Kong University of Science and...

220

Oak Ridge National Laboratory National Security Programs  

E-Print Network [OSTI]

Oak Ridge National Laboratory National Security Programs Dr. Michael A. Kuliasha, Chief Scientist National Security Technologies Oak Ridge National Laboratory #12;2 OAK RIDGE NATIONAL LABORATORY U. S Security Challenges #12;3 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY How Will Our Enemies

Note: This page contains sample records for the topic "national spherical torus" from the National Library of EnergyBeta (NLEBeta).
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221

Fire Safety Tests for Spherical Resorcinol Formaldehyde Resin: Data Summary Report  

SciTech Connect (OSTI)

A draft safety evaluation of the scenario for spherical resorcinol-formaldehyde (SRF) resin fire inside the ion exchange column was performed by the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Fire Safety organization. The result of this draft evaluation suggested a potential change of the fire safety classification for the Cesium Ion Exchange Process System (CXP) emergency elution vessels, equipment, and piping, which may be overly bounding based on the fire performance data from the manufacturer of the ion exchange resin selected for use at the WTP. To resolve this question, the fire properties of the SRF resin were measured by Southwest Research Institute (SwRI), following the American Society for Testing and Materials (ASTM) standard procedures, through a subcontract managed by Pacific Northwest National Laboratory (PNNL). For some tests, the ASTM standard procedures were not entirely appropriate or practical for the SRF resin material, so the procedures were modified and deviations from the ASTM standard procedures were noted. This report summarizes the results of fire safety tests performed and reported by SwRI. The efforts by PNNL were limited to summarizing the test results provided by SwRI into one consolidated data report. All as-received SwRI reports are attached to this report in the Appendix. Where applicable, the precision and bias of each test method, as given by each ASTM standard procedure, are included and compared with the SwRI test results of the SRF resin.

Kim, Dong-Sang; Peterson, Reid A.; Schweiger, Michael J.

2012-07-30T23:59:59.000Z

222

Fire Safety Tests for Cesium-Loaded Spherical Resorcinol Formaldehyde Resin: Data Summary Report  

SciTech Connect (OSTI)

A draft safety evaluation of the scenario for spherical resorcinol formaldehyde (SRF) resin fire inside the ion exchange column was performed by the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Fire Safety organization. The result of this draft evaluation suggested a potential change of the fire safety classification for the Cesium Ion Exchange Process System (CXP) emergency elution vessels, equipment, and piping. To resolve this question, the fire properties of the SRF resin were measured by Southwest Research Institute (SwRI) through a subcontract managed by Pacific Northwest National Laboratory (PNNL). The results of initial fire safety tests on the SRF resin were documented in a previous report (WTP-RPT-218). The present report summarizes the results of additional tests performed by SwRI on the cesium-loaded SRF resin. The efforts by PNNL were limited to summarizing the test results provided by SwRI into one consolidated data report. The as-received SwRI report is attached to this report in the Appendix A. Where applicable, the precision and bias of each test method, as given by each American Society for Testing and Materials (ASTM) standard procedure, are included and compared with the SwRI test results of the cesium-loaded SRF resin.

Kim, Dong-Sang; Schweiger, Michael J.; Peterson, Reid A.

2012-09-01T23:59:59.000Z

223

Spherically symmetric solutions and gravitational collapse in brane-worlds  

SciTech Connect (OSTI)

We consider spherically symmetric solutions within the context of brane-world theory without mirror symmetry or any form of junction conditions. For a constant curvature bulk, we obtain the modified Tolman-Oppenheimer-Volkoff (TOV) interior solutions in two cases where one is matched to a schwarzschild-de Sitter exterior while the other is consistent with an exterior solution whose structure can be used to explain the galaxy rotation curves without postulating dark matter. We also find the upper bound to the mass of a static brane-world star and show that the influence of the bulk effects on the interior solutions is small. Finally, we investigate the gravitational collapse on the brane and show that the exterior of a collapsing star can be static in this scenario.

Heydari-Fard, Malihe [Department of Physics, The University of Qom, Qom 37185-359 (Iran, Islamic Republic of)] [Department of Physics, The University of Qom, Qom 37185-359 (Iran, Islamic Republic of); Sepangi, Hamid R., E-mail: heydarifard@qom.ac.ir, E-mail: hr-sepangi@sbu.ac.ir [Department of Physics, Shahid Beheshti University, Evin, Tehran 19839 (Iran, Islamic Republic of)

2009-02-15T23:59:59.000Z

224

Reactive self-heating model of aluminum spherical nanoparticles  

E-Print Network [OSTI]

Aluminum-oxygen reaction is important in many highly energetic, high pressure generating systems. Recent experiments with nanostructured thermites suggest that oxidation of aluminum nanoparticles occurs in a few microseconds. Such rapid reaction cannot be explained by a conventional diffusion-based mechanism. We present a rapid oxidation model of a spherical aluminum nanoparticle, using Cabrera-Mott moving boundary mechanism, and taking self-heating into account. In our model, electric potential solves the nonlinear Poisson equation. In contrast with the Coulomb potential, a "double-layer" type solution for the potential and self-heating leads to enhanced oxidation rates. At maximal reaction temperature of 2000 C, our model predicts overall oxidation time scale in microseconds range, in agreement with experimental evidence.

Karen S. Martirosyan; Maxim Zyskin

2012-12-17T23:59:59.000Z

225

Static spherically symmetric black holes with scalar field  

E-Print Network [OSTI]

Static spherically symmetric black holes and particle like solutions with self interacting minimally coupled scalar field {\\phi} are analyzed. They are asymptotically flat or anti-de Sitter (AdS). We express them in terms of a single function {\\rho} which undergoes simple conditions. If {\\phi} is nontrivial the ADM mass M has to be positive. No-hair theorems are generalized to the AdS asymptotic. For both asymptotics the Killing horizon is nondegenerate and its radius cannot be bigger than 2M. Derivatives of {\\rho} at singularity determine properties of admissible potentials V({\\phi}) as regularity, boundedness and behaviour for maximal values of {\\phi}. Several classes of solutions with singular or nonsingular potentials are obtained. Their examples are presented in a form of plots.

J. Tafel

2013-06-16T23:59:59.000Z

226

On the gravitational self-energy of a spherical shell  

E-Print Network [OSTI]

According to Einstein's mass-energy equivalence, a body with a given mass extending in a large region of space, will get a smaller mass when confined into a smaller region, because of its own gravitational energy. The classical self-energy problem has been studied in the past in connection with the renormalization of a charged point particle. Still exact consistent solutions have not been thoroughly discussed in the simpler framework of Newtonian gravity. Here we exploit a spherical symmetrical shell model and find two possible solutions, depending on some additional assumption. The first solution goes back to Arnowitt, Deser and Misner (1960). The second is new and yields a new vanishingly small value (10^-55 cm) for the classical electron radius.

G. Dillon

2013-03-14T23:59:59.000Z

227

Improved first order mean spherical approximation for simple fluids  

E-Print Network [OSTI]

A perturbation approach based on the first-order mean spherical approximation (FMSA) is proposed. It consists in adopting a hard-sphere plus short-range attractive Yukawa fluid as the novel reference system, over which the perturbative solution of the Ornstein-Zernike equation is performed. A choice of the optimal range of the reference attraction is discussed. The results are compared against conventional FMSA/HS theory and Monte-Carlo simulation data for compressibility factor and vapor-liquid phase diagrams of the medium-ranged Yukawa fluid. Proposed theory keeps the same level of simplicity and transparency, as the conventional FMSA/HS approach does, but shows to be more accurate.

S. Hlushak; A. Trokhymchuk; I. Nezbeda

2012-02-20T23:59:59.000Z

228

Spherically symmetric cosmological spacetimes with dust and radiation numerical implementation  

SciTech Connect (OSTI)

We present new numerical cosmological solutions of the Einstein Field Equations. The spacetime is spherically symmetric with a source of dust and radiation approximated as a perfect fluid. The dust and radiation are necessarily non-comoving due to the inhomogeneity of the spacetime. Such a model can be used to investigate non-linear general relativistic effects present during decoupling or big-bang nucleosynthesis, as well as for investigating void models of dark energy with isocurvature degrees of freedom. We describe the full evolution of the spacetime as well as the redshift and luminosity distance for a central observer. After demonstrating accuracy of the code, we consider a few example models, and demonstrate the sensitivity of the late time model to the degree of inhomogeneity of the initial radiation contrast.

Lim, Woei Chet [Department of Mathematics, University of Waikato, Private Bag 3105, Hamilton 3240 (New Zealand); Regis, Marco [Dipartimento di Fisica, Universit di Torino and INFN, Torino (Italy); Clarkson, Chris, E-mail: wclim@waikato.ac.nz, E-mail: regis@to.infn.it, E-mail: chris.clarkson@gmail.com [Astrophysics, Cosmology and Gravity Centre, and Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa)

2013-10-01T23:59:59.000Z

229

Brane solutions of a spherical sigma model in six dimensions  

E-Print Network [OSTI]

We explore solutions of six dimensional gravity coupled to a non-linear sigma model, in the presence of co-dimension two branes. We investigate the compactifications induced by a spherical scalar manifold and analyze the conditions under which they are of finite volume and singularity free. We discuss the issue of single-valuedness of the scalar fields and provide some special embedding of the scalar manifold to the internal space which solves this problem. These brane solutions furnish some self-tuning features, however they do not provide a satisfactory explanation of the vanishing of the effective four dimensional cosmological constant. We discuss the properties of this model in relation with the self-tuning example based on a hyperbolic sigma model.

Hyun Min Lee; Antonios Papazoglou

2004-11-16T23:59:59.000Z

230

A simple procedure to prepare spherical {alpha}-alumina powders  

SciTech Connect (OSTI)

Spherical {alpha}-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of {alpha}-alumina powders. The precursors crystallized to {gamma}-alumina at 1000 deg. C and converted to {alpha}-alumina at 1150 deg. C without intermediate phases. The particle morphology of precursor was retained after it crystallized to {alpha}-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to {alpha}-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products.

Liu Hongyu [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Ning Guiling [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)], E-mail: ninggl@dlut.edu.cn; Gan Zhihong; Lin Yuan [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)

2009-04-02T23:59:59.000Z

231

Regularization of spherical and axisymmetric evolution codes in numerical relativity  

E-Print Network [OSTI]

Several interesting astrophysical phenomena are symmetric with respect to the rotation axis, like the head-on collision of compact bodies, the collapse and/or accretion of fields with a large variety of geometries, or some forms of gravitational waves. Most current numerical relativity codes, however, can not take advantage of these symmetries due to the fact that singularities in the adapted coordinates, either at the origin or at the axis of symmetry, rapidly cause the simulation to crash. Because of this regularity problem it has become common practice to use full-blown Cartesian three-dimensional codes to simulate axi-symmetric systems. In this work we follow a recent idea idea of Rinne and Stewart and present a simple procedure to regularize the equations both in spherical and axi-symmetric spaces. We explicitly show the regularity of the evolution equations, describe the corresponding numerical code, and present several examples clearly showing the regularity of our evolutions.

Milton Ruiz; Miguel Alcubierre; Dario Nunez

2007-09-11T23:59:59.000Z

232

On spherically-symmetric accretion by a collisionless polytrope  

E-Print Network [OSTI]

An isolated, spherically-symmetric, self-gravitating, collisionless system is always a polytrope when it reaches equilibrium (Nakamura 2000). This strongly suggests as a corollary, however, that the same polytrope dominates its precursor states, since the dynamical equations for its constituents can be time-reversed. Moreover this assumption, which precludes a polytrope from ever accreting 100% of the mass from an infalling shell, as a subsequent state will eventually be a polytrope, is confirmed now by our finding that a collisionless polytrope cannot accrete 100% of an infalling shell while simultaneously guaranteeing that the entropy of the Universe as a whole increases. These strictures are only evaded by the shedding of some mass. A polytrope must lose mass to gain mass. We deduce from the time-reversible property of a collisionless polytrope that the scalar sum, P, over constituent momenta in its rest frame is an independent state variable that is conserved with respect to its surface radius through interactions between a polytrope and an infalling shell. This new constraint, together with conservation of energy, enables us (i) to show that an isolated polytrope is indeed stable against spherically-symmetric mass-loss, which is the essential content of our initial assumption; (ii) to calculate both the velocity and the fraction of infall-mass returned to infinity, provided the "accretion law" between the change in mass and surface radius is specified. Numerical results confirm a frequent empirical finding (Livio 2000) that the velocity of a mass outflow is of the same order of magnitude as the escape velocity from the system.

B. M. Lewis

2001-04-02T23:59:59.000Z

233

National RF Test Facility as a multipurpose development tool  

SciTech Connect (OSTI)

Additions and modifications to the National RF Test Facility design have been made that (1) focus its use for technology development for future large systems in the ion cyclotron range of frequencies (ICRF), (2) expand its applicability to technology development in the electron cyclotron range of frequencies (ECRF) at 60 GHz, (3) provide a facility for ELMO Bumpy Torus (EBT) 60-GHz ring physics studies, and (4) permit engineering studies of steady-state plasma systems, including superconducting magnet performance, vacuum vessel heat flux removal, and microwave protection. The facility will continue to function as a test bed for generic technology developments for ICRF and the lower hybrid range of frequencies (LHRF). The upgraded facility is also suitable for mirror halo physics experiments.

McManamy, T.J.; Becraft, W.R.; Berry, L.A.; Blue, C.W.; Gardner, W.L.; Haselton, H.H.; Hoffman, D.J.; Loring, C.M. Jr.; Moeller, F.A.; Ponte, N.S.

1983-01-01T23:59:59.000Z

234

Self-interaction-free density-functional theoretical study of the electronic structure of spherical and vertical quantum dots  

E-Print Network [OSTI]

ca qu T nte pu ef pt pro si sc st em l n an d ith r ity along the vertical direction. Due to such strong confine- PHYSICAL REVIEW B, VOLUME 63, 045317atoms. The number of electrons in a quantum dot N can be controlled experimentally, allowing..., the total energy of a 3D spherical har- monic oscillator is Enrlm5S 2nr1l1 3 2 Dv5S N1 3 2 Dv , ~40! where nr50,1,2,3, . . . , and N52nr1l . We use the desig- nation (nr ,l) to denote the energy level with the radial quan- tum numbers nr and the orbital...

Jiang, T. F.; Tong, Xiao-Min; Chu, Shih-I

2001-01-09T23:59:59.000Z

235

Tomographic analysis of neutron and gamma pulse shape distributions from liquid scintillation detectors at Joint European Torus  

SciTech Connect (OSTI)

The Joint European Torus (JET, Culham, UK) is the largest tokamak in the world devoted to nuclear fusion experiments of magnetic confined Deuterium (D)/Deuterium-Tritium (DT) plasmas. Neutrons produced in these plasmas are measured using various types of neutron detectors and spectrometers. Two of these instruments on JET make use of organic liquid scintillator detectors. The neutron emission profile monitor implements 19 liquid scintillation counters to detect the 2.45 MeV neutron emission from D plasmas. A new compact neutron spectrometer is operational at JET since 2010 to measure the neutron energy spectra from both D and DT plasmas. Liquid scintillation detectors are sensitive to both neutron and gamma radiation but give light responses of different decay time such that pulse shape discrimination techniques can be applied to identify the neutron contribution of interest from the data. The most common technique consists of integrating the radiation pulse shapes within different ranges of their rising and/or trailing edges. In this article, a step forward in this type of analysis is presented. The method applies a tomographic analysis of the 3-dimensional neutron and gamma pulse shape and pulse height distribution data obtained from liquid scintillation detectors such that n/? discrimination can be improved to lower energies and additional information can be gained on neutron contributions to the gamma events and vice versa.

Giacomelli, L. [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom) [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Department of Physics, Universit degli Studi di Milano-Bicocca, Milano (Italy); Conroy, S. [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom) [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Department of Physics and Astronomy, Uppsala University, Uppsala (Sweden); Gorini, G. [Department of Physics, Universit degli Studi di Milano-Bicocca, Milano (Italy)] [Department of Physics, Universit degli Studi di Milano-Bicocca, Milano (Italy); Horton, L.; Murari, A.; Popovichev, S.; Syme, D. B. [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)] [JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)

2014-02-15T23:59:59.000Z

236

Identification of the hardening law of materials with spherical indentation using the average  

E-Print Network [OSTI]

the load-displacement curve of a spherical indentation test is proposed. This method is based on the use tensile test [19] . Identification of plastic hardening parameters from a load-penetration depth spherical indentation curve (F-h curve) is mostly used and the methods based on the representative strain

237

An exact solution for the Casimir force in a spherically symmetric medium  

E-Print Network [OSTI]

We calculated the force of the quantum vacuum, the Casimir force, in a spherically symmetric medium, Maxwell's fish eye, surrounded by a perfect mirror and derived an exact analytic solution. Our solution questions the idea that the Casimir force of a spherical mirror is repulsive - we found an attractive force that diverges at the mirror.

Ulf Leonhardt; William M. R. Simpson

2011-07-03T23:59:59.000Z

238

Trajectory Planning and Control of an Underactuated Dynamically Stable Single Spherical Wheeled Mobile Robot  

E-Print Network [OSTI]

Trajectory Planning and Control of an Underactuated Dynamically Stable Single Spherical Wheeled is a dynamically stable mobile robot that moves on a single spherical wheel and is capable of omni- directional movement. The ballbot is an underactuated system with nonholonomic dynamic constraints. The authors propose

239

Processes for making dense, spherical active materials for lithium-ion cells  

DOE Patents [OSTI]

Processes are provided for making dense, spherical mixed-metal carbonate or phosphate precursors that are particularly well suited for the production of active materials for electrochemical devices such as lithium ion secondary batteries. Exemplified methods include precipitating dense, spherical particles of metal carbonates or metal phosphates from a combined aqueous solution using a precipitating agent such as ammonium hydrogen carbonate, sodium hydrogen carbonate, or a mixture that includes sodium hydrogen carbonate. Other exemplified methods include precipitating dense, spherical particles of metal phosphates using a precipitating agent such as ammonium hydrogen phosphate, ammonium dihydrogen phosphate, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, or a mixture of any two or more thereof. Further provided are compositions of and methods of making dense, spherical metal oxides and metal phosphates using the dense, spherical metal precursors. Still further provided are electrodes and batteries using the same.

Kang, Sun-Ho (Naperville, IL); Amine, Khalil (Downers Grove, IL)

2011-11-22T23:59:59.000Z

240

National Laboratory Impact Initiative  

Broader source: Energy.gov [DOE]

The National Laboratory Impact Initiative supports the relationship between the Office of Energy Efficiency & Renewable Energy and the national laboratory enterprise. The national laboratories...

Note: This page contains sample records for the topic "national spherical torus" 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

National System Templates: Building Sustainable National Inventory...  

Open Energy Info (EERE)

Templates: Building Sustainable National Inventory Management Systems Jump to: navigation, search Tool Summary LAUNCH TOOL Name: National System Templates: Building Sustainable...

242

Local Casimir Energies for a Thin Spherical Shell  

E-Print Network [OSTI]

The local Casimir energy density for a massless scalar field associated with step-function potentials in a 3+1 dimensional spherical geometry is considered. The potential is chosen to be zero except in a shell of thickness $\\delta$, where it has height $h$, with the constraint $h\\delta=1$. In the limit of zero thickness, an ideal $\\delta$-function shell is recovered. The behavior of the energy density as the surface of the shell is approached is studied in both the strong and weak coupling regimes. The former case corresponds to the well-known Dirichlet shell limit. New results, which shed light on the nature of surface divergences and on the energy contained within the shell, are obtained in the weak coupling limit, and for a shell of finite thickness. In the case of zero thickness, the energy has a contribution not only from the local energy density, but from an energy term residing entirely on the surface. It is shown that the latter coincides with the integrated local energy density within the shell. We also study the dependence of local and global quantities on the conformal parameter. In particular new insight is provided on the reason for the divergence in the global Casimir energy in third order in the coupling.

Ines Cavero-Pelaez; Kimball A. Milton; Jeffrey Wagner

2006-02-01T23:59:59.000Z

243

Geodesic Particle Paths Inside a Nonrotating, Homogeneous, Spherical Body  

E-Print Network [OSTI]

Proceeding from a solution of field equations that are improved versions of Einstein's nonvacuum gravitational field equations one is able to calculate precisely the trajectories of particles traveling inside a nonrotating, homogeneous, spherical body. Application of the results to the conditions of recent measurements of neutrino flight times between a source point A at CERN's European Laboratory for Particle Physics and a point B in either of two detectors (ICARUS or OPERA) at LNGS (Laboratori Nazionale del Gran Sasso), separated by a euclidean distance d(A,B) = 731 km, predicts for the flight time from A to B of a 2 eV neutrino launched with energy 17 GeV, as measured by a clock at B synchronized to a similar clock at A, approximately d/c + 9.3 x 10^{-16} sec. But as measured by inertial observers along the path the predicted flight time is approximately d/c - 2.6 x 10^{-9} sec and the predicted path length is approximately d - 8.4 x 10^{-7} m, which yields c + 321 m/sec for the predicted average inertially referenced speed of the neutrino from A to B.

Homer G. Ellis

2012-10-18T23:59:59.000Z

244

Spherical Collapse Model And Dark Energy(I)  

E-Print Network [OSTI]

In existing literatures about the top-hat spherical collapse model of galaxy clusters formation in cosmology containing dark energies, dark energies are usually assumed not to cluster on this scale. But all these literatures ignored the current describing the flowing of dark energies outside the clusters which should exist under this assumption, so the conclusions of these literatures are worth further explorations. In this paper we study this model in QCDM or Phantom-CDM cosmologies(flat) by assuming that dark energies will cluster synchronously with ordinary matters on the scale of galaxy clusters so the dark energy current flowing outside the clusters does not exist at all and find that in this case, the key parameters of the model exhibit rather non-trivial and remarkable dependence on the equation of state coefficients of dark energies. We then apply the results in Press-Scheter theory and calculate the number density of galaxy clusters and its evolutions. We find that this two quantities are both affected exponentially by the equation of state coefficients of dark energies. We leave the study of this model with the assumption that dark energies do not cluster on the scale of galaxy clusters at all as the topic of another paper where similar conclusions will be obtained also.

Ding-fang Zeng; Yi-hong Gao

2005-05-09T23:59:59.000Z

245

Analysis of spherically symmetric black holes in Braneworld models  

E-Print Network [OSTI]

Research on black holes and their physical proprieties has been active on last 90 years. With the appearance of the String Theory and the Braneworld models as alternative descriptions of our Universe, the interest on black holes, in these context, increased. In this work we studied black holes in Braneworld models. A class of spherically symmetric black holes is investigaded as well its stability under general perturbations. Thermodynamic proprieties and quasi-normal modes are discussed. The black holes studied are the SM (zero mass) and CFM solutions, obtained by Casadio {\\it et al.} and Bronnikov {\\it et al.}. The geometry of bulk is unknown. However the Campbell-Magaard Theorem guarantees the existence of a 5-dimensional solution in the bulk whose projection on the brane is the class of black holes considered. They are stable under scalar perturbations. Quasi-normal modes were observed in both models. The tail behavior of the perturbations is the same. The entropy upper bound of a body absorved by the black holes studied was calculated. This limit turned out to be independent of the black hole parameters.

A. B. Pavan

2010-05-25T23:59:59.000Z

246

Fractal boundary basins in spherically symmetric $?^4$ theory  

E-Print Network [OSTI]

Results are presented from numerical simulations of the flat-space nonlinear Klein-Gordon equa- tion with an asymmetric double-well potential in spherical symmetry. Exit criteria are defined for the simulations that are used to help understand the boundaries of the basins of attraction for Gaussian "bubble" initial data. The first exit criteria, based on the immediate collapse or expan- sion of bubble radius, is used to observe the departure of the scalar field from a static intermediate attractor solution. The boundary separating these two behaviors in parameter space is smooth and demonstrates a time-scaling law with an exponent that depends on the asymmetry of the potential. The second exit criteria differentiates between the creation of an expanding true-vacuum bubble and dispersion of the field leaving the false vacuum; the boundary separating these basins of attraction is shown to demonstrate fractal behavior. The basins are defined by the number of bounces that the field undergoes before inducing a phase transition. A third, hybrid exit criteria is used to determine the location of the boundary to arbitrary precision and to characterize the threshold behavior. The possible effects this behavior might have on cosmological phase transitions are briefly discussed.

Ethan P. Honda

2011-06-14T23:59:59.000Z

247

THE SPHERICALIZATION OF DARK MATTER HALOS BY GALAXY DISKS  

SciTech Connect (OSTI)

Cosmological simulations indicate that cold dark matter (CDM) halos should be triaxial. Validating this theoretical prediction is, however, less than straightforward because the assembly of galaxies is expected to modify halo shapes and to render them more axisymmetric. We use a suite of N-body simulations to quantitatively investigate the effect of the growth of a central disk galaxy on the shape of triaxial dark matter halos. In most circumstances, the halo responds to the presence of the disk by becoming more spherical. The net effect depends weakly on the timescale of the disk assembly but noticeably on the orientation of the disk relative to the halo principal axes, and it is maximal when the disk symmetry axis is aligned with the major axis of the halo. The effect depends most sensitively on the overall gravitational importance of the disk. Our results indicate that exponential disks whose contribution peaks at less than {approx}50% of their circular velocity are unable to noticeably modify the shape of the gravitational potential of their surrounding halos. Many dwarf and low surface brightness galaxies are expected to be in this regime, and therefore their detailed kinematics could be used to probe halo triaxiality, one of the basic predictions of the CDM paradigm. We argue that the complex disk kinematics of the dwarf galaxy NGC 2976 might be the reflection of a triaxial halo. Such signatures of halo triaxiality should be common in galaxies where the luminous component is subdominant.

Kazantzidis, Stelios [Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Abadi, Mario G. [Instituto de Astronomia Teorica y Experimental (IATE), Observatorio Astronomico de Cordoba and CONICET, Laprida 854 X5000BGR Cordoba (Argentina); Navarro, Julio F., E-mail: stelios@mps.ohio-state.ed, E-mail: mario@oac.uncor.ed, E-mail: jfn@uvic.c [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2 (Canada)

2010-09-01T23:59:59.000Z

248

Numerical Relativity in Spherical Polar Coordinates: Off-center Simulations  

E-Print Network [OSTI]

We have recently presented a new approach for numerical relativity simulations in spherical polar coordinates, both for vacuum and for relativistic hydrodynamics. Our approach is based on a reference-metric formulation of the BSSN equations, a factoring of all tensor components, as well as a partially implicit Runge-Kutta method, and does not rely on a regularization of the equations, nor does it make any assumptions about the symmetry across the origin. In order to demonstrate this feature we present here several off-centered simulations, including simulations of single black holes and neutron stars whose center is placed away from the origin of the coordinate system, as well as the asymmetric head-on collision of two black holes. We also revisit our implementation of relativistic hydrodynamics and demonstrate that a reference-metric formulation of hydrodynamics together with a factoring of all tensor components avoids problems related to the coordinate singularities at the origin and on the axes. As a parti...

Baumgarte, Thomas W; Mller, Ewald

2015-01-01T23:59:59.000Z

249

Self Assembled Clusters of Spheres Related to Spherical Codes  

E-Print Network [OSTI]

We consider the thermodynamically driven self-assembly of spheres onto the surface of a central sphere. This assembly process forms self-limiting, or terminal, anisotropic clusters (N-clusters) with well defined structures. We use Brownian dynamics to model the assembly of N-clusters varying in size from two to twelve outer spheres, and free energy calculations to predict the expected cluster sizes and shapes as a function of temperature and inner particle diameter. We show that the arrangements of outer spheres at finite temperatures are related to spherical codes, an ideal mathematical sequence of points corresponding to densest possible sphere packings. We demonstrate that temperature and the ratio of the diameters of the inner and outer spheres dictate cluster morphology and dynamics. We find that some N-clusters exhibit collective particle rearrangements, and these collective modes are unique to a given cluster size N. We present a surprising result for the equilibrium structure of a 5-cluster, which prefers an asymmetric square pyramid arrangement over a more symmetric arrangement. Our results suggest a promising way to assemble anisotropic building blocks from constituent colloidal spheres.

Carolyn L. Phillips; Eric Jankowski; Michelle Marval; Sharon C. Glotzer

2012-01-24T23:59:59.000Z

250

National Security  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell Batteries &NST DivisionNationalEnergy

251

National Laboratory  

Office of Scientific and Technical Information (OSTI)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart ofMeasuringInformationOffice ofEnergy, OfficeUS Dept

252

National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andData andFleetEngineeringAnnual ReportNational Lab Day -

253

National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andData andFleetEngineeringAnnual ReportNational Lab Day -draws more

254

NSTX Weekly Report (May 21, 2010) FY 2010 NSTX plasma operations  

E-Print Network [OSTI]

Diagnostics for Liquid Lithium Divertor Studies on the National Spherical Torus Experiment" by V University), "Modeling the Polarization Properties of Propagating Electromagnetic Waves in NSTX" by J. Zhang Plasma Physics and Plasma Material Interactions in the Fusion Power Plant Regime" 20-21 May 2010 at UC

Princeton Plasma Physics Laboratory

255

DIMENSIONS of DISCOVERY Sponsored Program Awards  

E-Print Network [OSTI]

of a Stent Prototype to Induce Closure of Post-Traumatic Blast-Induced Pseudo-Aneurysms; Modification 1) and its Effect on High Performance Plasmas in National Spherical Torus Experiment (NSTX)." Allebach, Jan P." Applegate, Todd J; animal sciences, from Purac, $43,632, "Effect of Form and Dos- age of Lactylate

Ginzel, Matthew

256

PREPARED FOR THE U.S. DEPARTMENT OF ENERGY, UNDER CONTRACT DE-AC02-76CH03073  

E-Print Network [OSTI]

of Beam Driven Modes during Neutral Beam Heating on the National Spherical Torus Experiment by E Publications and Reports web site in FiscaL Year 2002. The home page for PPPL Reports and Publications is: http-8547 Internet: http://www.ntis.gov/ordering.htm #12;Observation of Beam Driven Modes during Neutral Beam Heating

257

PREPARED FOR THE U.S. DEPARTMENT OF ENERGY, UNDER CONTRACT DE-AC02-76CH03073  

E-Print Network [OSTI]

in Calendar Year 2001. The home page for PPPL Reports and Publications is: http://www.pppl.gov/pub_report/ DOE, Princeton, New Jersey 08543, USA Abstract Neutral beam (NB) heating in the National Spherical Torus auxiliary heating. NB heating experiments in NSTX began in September 2000 using up to 5 MW of 80 keV D beams

258

Suggestions Regarding US-International Collaboration on Tokamak Magnetic Fusion Research Steven A. Sabbagh Columbia University 12/14/11 v1  

E-Print Network [OSTI]

. Sabbagh ­ Columbia University 12/14/11 v1 Dear Dale and the FESAC International Collaboration Panel Professor of Applied Physics Columbia University National Spherical Torus Experiment Run Coordinator. Sabbagh ­ Columbia University 12/14/11 v1 Suggestions are arranged in the following manner: (A) Research

259

An "adiabatic-hindered-rotor" treatment allows para-H2 to be treated as if it were spherical  

E-Print Network [OSTI]

An "adiabatic-hindered-rotor" treatment allows para-H2 to be treated as if it were spherical Hui Li­ molecule interactions, the common assumption that para-H2 may be treated as a spherical particle is often K , it is often considered a good approximation to treat para-H2 as a spherical particle.1

Le Roy, Robert J.

260

New framework for studying spherically symmetric static solutions in f(R) gravity  

SciTech Connect (OSTI)

We develop a new covariant formalism to treat spherically symmetric spacetimes in metric f(R) theories of gravity. Using this formalism we derive the general equations for a static and spherically symmetric metric in a general f(R) gravity. These equations are used to determine the conditions for which the Schwarzschild metric is the only vacuum solution with vanishing Ricci scalar. We also show that our general framework provides a clear way of showing that the Schwarzschild solution is not a unique static spherically symmetric solution, providing some insight into how the current form of Birkhoff's theorem breaks down for these theories.

Nzioki, Anne Marie; Goswami, Rituparno [Astrophysics, Cosmology and Gravity Centre (ACGC), University of Cape Town, Rondebosch, 7701 (South Africa); Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch, 7701 (South Africa); Carloni, Sante [Institut d'Estudis Espacials de Catalunya (IEEC), Campus UAB, Facultat Ciencies, Torre C5-Par-2a pl, E-08193 Bellaterra (Barcelona) (Spain); Dunsby, Peter K. S. [Astrophysics, Cosmology and Gravity Centre (ACGC), University of Cape Town, Rondebosch, 7701 (South Africa); Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch, 7701 (South Africa); South African Astronomical Observatory, Observatory, Cape Town (South Africa)

2010-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Energy-momentum Prescriptions in General Spherically Symmetric Space-times  

E-Print Network [OSTI]

Einstein, Landau-Lifshitz, Papapetrou, Weinberg, and M{\\o}ller energy-momentum prescriptions in general spherically symmetric space-times are investigated. It is shown that for two special but not unusual classes of general spherically symmetric space-times several energy-momentum prescriptions in Schwarzschild Cartesian coordinates lead to some coincidences in energy distribution. It is also obtained that for a special class of spherically symmetric metrics M{\\o}ller and Einstein energy-momentum prescriptions give the same result for energy distribution if and only if it has a specific dependence on radial coordinate.

Saeed Mirshekari; Amir M. Abbassi

2014-11-29T23:59:59.000Z

262

WILDLIFE REFUGE BACA NATIONAL  

E-Print Network [OSTI]

Rio Grande National Forest Rio Grande National Forest San Isabel National Forest Solar Energy Study Great Sand Dunes National Preserve 285 160 160 160 285 Carson National Forest Grand Mesa National Forest Note 2) (As of 6/5/2009) Solar Energy Study Area (As of 6/5/2009) BLM Lands Being Analyzed for Solar

Laughlin, Robert B.

263

Dynamical separation of spherical bodies in supersonic flow  

SciTech Connect (OSTI)

An experimental and computational investigation of the unsteady separation behaviour of two spheres in a highly supersonic flow is carried out. The spherical bodies, initially touching, are released with negligible relative velocity, an arrangement representing the idealized binary fragmentation of a meteoritic body in the atmosphere. In experiments performed in a Mach-4 Ludwieg tube, nylon spheres are initially suspended in the test section by weak threads and, following detachment of the threads by the arrival of the flow, fly freely according to the aerodynamic forces experienced. The resulting sphere motions and unsteady flow structures are recorded using high-speed shadowgraphy. The qualitative separation behaviour and the final lateral velocity of the smaller sphere are found to vary strongly with both the radius ratio and the initial alignment angle of the two spheres. More disparate radii and initial configurations in which the smaller sphere centre lies downstream of that of the larger sphere both increase the tendency for the smaller sphere to be entrained within the flow region bounded by the bow-shock of the larger body, rather than expelled from this region. At a critical angle for a given radius ratio (or a critical radius ratio for a given angle), transition from entrainment to expulsion occurs; at this critical value, the final lateral velocity is close to maximum due to the surfing effect noted by Laurence & Deiterding (J. Fluid Mech., vol. 676, 2011, pp. 396-431) at hypersonic Mach numbers. A high-precision tracking algorithm is used to provide quantitative comparisons between experiments and high-resolution inviscid numerical simulations, with generally favourable agreement.

Laurence, Stuart J [Institute of Aerodynamics and Flow Technology, German Aerospace Center; Parziale, Nick J [California Institute of Technology, Pasadena; Deiterding, Ralf [ORNL

2012-01-01T23:59:59.000Z

264

A classification of spherically symmetric self-similar dust models  

E-Print Network [OSTI]

We classify all spherically symmetric dust solutions of Einstein's equations which are self-similar in the sense that all dimensionless variables depend only upon $z\\equiv r/t$. We show that the equations can be reduced to a special case of the general perfect fluid models with equation of state $p=\\alpha \\mu$. The most general dust solution can be written down explicitly and is described by two parameters. The first one (E) corresponds to the asymptotic energy at large $|z|$, while the second one (D) specifies the value of z at the singularity which characterizes such models. The E=D=0 solution is just the flat Friedmann model. The 1-parameter family of solutions with z>0 and D=0 are inhomogeneous cosmological models which expand from a Big Bang singularity at t=0 and are asymptotically Friedmann at large z; models with E>0 are everywhere underdense relative to Friedmann and expand forever, while those with E0 ones. The 2-parameter solutions with D>0 again represent inhomogeneous cosmological models but the Big Bang singularity is at $z=-1/D$, the Big Crunch singularity is at $z=+1/D$, and any particular solution necessarily spans both z0. While there is no static model in the dust case, all these solutions are asymptotically ``quasi-static'' at large $|z|$. As in the D=0 case, the ones with $E \\ge 0$ expand or contract monotonically but the latter may now contain a naked singularity. The ones with E<0 expand from or recollapse to a second singularity, the latter containing a black hole.

B. J. Carr

2000-03-02T23:59:59.000Z

265

MFE Concept Integration and Performance Measures Magnetic Fusion Concept Working Group  

E-Print Network [OSTI]

, spherical torus, compact stellarator, reversed-field pinch, and spheromak The goal was to identify, for each

266

Radio emission from weak spherical shocks in the outskirts of galaxy clusters  

E-Print Network [OSTI]

In Kang (2015) we calculated the acceleration of cosmic-ray electrons and the ensuing radio synchrotron emission at weak spherical shocks that are expected to form in the outskirts of galaxy clusters.There we demonstrated that, at decelerating spherical shocks, the volume integrated spectra of both electrons and radiation deviate significantly from the test-particle power-laws predicted for constant planar shocks, because the shock compression ratio and the flux of injected electrons decrease in time. In this study, we consider spherical blast waves propagating into a constant density core surrounded by an isothermal halo with a decreasing density profile in order to explore how the deceleration rate of the shock speed affects the radio emission from accelerated electrons. The surface brightness profile and the volume-integrated radio spectrum of the model shocks are calculated by assuming a ribbon-like shock surface on a spherical shell and the associated downstream region of relativistic electrons. If the p...

Kang, Hyesung

2015-01-01T23:59:59.000Z

267

Experimental hydrodynamics of spherical projectiles impacting on a free surface using high speed imaging techniques  

E-Print Network [OSTI]

This thesis looks at the hydrodynamics of spherical projectiles impacting the free surface using a unique experimental WebLab facility. Experiments were performed to determine the force impact coefficients of spheres and ...

Laverty, Stephen Michael

2005-01-01T23:59:59.000Z

268

Conformally flat Einstein-Yang-Mills-Higgs solutions with spherical symmetry  

SciTech Connect (OSTI)

We solve the Einstein-Yang-Mills-Higgs equations in a conformally flat metric with spherical symmetry. Two solutions are obtained corresponding to magnetic monopoles in the Higgs vacuum and outside of it.

Mondaini, R.P.; Santos, N.O.

1983-10-15T23:59:59.000Z

269

Numerical Spherically Symmetric Static Solution of the RTG Equations Outside the Matter  

E-Print Network [OSTI]

There was obtained a numerical external solution for the exact system of the RTG equations with some natural boundary conditions in the static spherically symmetric case. The properties of the solution are discussed.

A. Godizov

2007-02-21T23:59:59.000Z

270

Spherically symmetric brane spacetime with bulk $f(\\mathcal{R})$ gravity  

E-Print Network [OSTI]

Introducing $f(\\mathcal{R})$ term in the five-dimensional bulk action we derive effective Einstein's equation on the brane using Gauss-Codazzi equation. This effective equation is then solved for different conditions on dark radiation and dark pressure to obtain various spherically symmetric solutions. Some of these static spherically symmetric solutions correspond to black hole solutions, with parameters induced from the bulk. Specially, the dark pressure and dark radiation terms (electric part of Weyl curvature) affect the brane spherically symmetric solutions significantly. We have solved for one parameter group of conformal motions where the dark radiation and dark pressure terms are exactly obtained exploiting the corresponding Lie symmetry. Various thermodynamic features of these spherically symmetric space-times are studied, showing existence of second order phase transition. This phenomenon has its origin in the higher curvature term with $f(\\mathcal{R})$ gravity in the bulk.

Sumanta Chakraborty; Soumitra SenGupta

2015-01-15T23:59:59.000Z

271

A two-phase spherical electric machine for generating rotating uniform magnetic fields  

E-Print Network [OSTI]

This thesis describes the design and construction of a novel two-phase spherical electric machine that generates rotating uniform magnetic fields, known as a fluxball machine. Alternative methods for producing uniform ...

Lawler, Clinton T. (Clinton Thomas)

2007-01-01T23:59:59.000Z

272

Plasma-Density Determination from X-Ray Radiography of Laser-Driven Spherical Implosions  

E-Print Network [OSTI]

The fuel layer density of an imploding laser-driven spherical shell is inferred from framed x-ray radiographs. The density distribution is determined by using Abel inversion to compute the radial distribution of the opacity ...

Frenje, Johan A.

273

Unitary representations of affine Hecke algebras related to Macdonald spherical functions  

E-Print Network [OSTI]

For any reduced crystallographic root system, we introduce a unitary representation of the (extended) affine Hecke algebra given by discrete difference-reflection operators acting in a Hilbert space of complex functions on the weight lattice. It is shown that the action of the center under this representation is diagonal on the basis of Macdonald spherical functions. As an application, we compute an explicit Pieri formula for these spherical functions.

J. F. van Diejen; E. Emsiz

2012-09-14T23:59:59.000Z

274

Facile fabrication of spherical nanoparticle-tipped AFM probes for plasmonic applications  

E-Print Network [OSTI]

for reliably producing metallic spherical nanoparticle tips using only a simple electrochemical cell. Fabrication of Au spherical nanoparticle (AuNP) tips onto commercial AFM probes is achieved using single-pulse high- fi eld electrochemical growth... is employed for growth since both the cell geometry and electrodeposition solution are kept the same between fabrications. AFM probes are attached to fl u- orine-doped tin oxide (FTO) conductive glass, used as a working DOI: 10.1002/ppsc.201400104 Facile...

Sanders, Alan; Zhang, Liwu; Bowman, Richard W.; Herrmann, Lars O.; Baumberg, Jeremy J.

2014-07-16T23:59:59.000Z

275

Group pyrolysis, ignition, and combustion of a spherical cloud of coal particles  

E-Print Network [OSTI]

GROUP PYROLYSIS, IGNITION, AND COMBUSTION OF A SPHERICAL CLOUD OF COAL PARTICLES A Thesis by WILLIAM RICHARD RYAN, JR. Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree MASTER OF SCIENCE December 1988 Major Subject: Mechanical Engineering GROUP PYROLYSIS, IGNITION, AND COMBUSTION OF A SPHERICAL CLOUD OF COAL PARTICLES A Thesis by WIL LI AM RI C HA RD RYA N ~ JR Approved ss to style and content by...

Ryan, William Richard

1988-01-01T23:59:59.000Z

276

Advances in neutral-beam-based diagnostics on the Madison Symmetric Torus reversed-field pinch (invited)  

SciTech Connect (OSTI)

Innovative charge-exchange recombination spectroscopy (CHERS), motional Stark effect (MSE), and Rutherford scattering diagnostics are now in operation on the Madison Symmetric Torus (MST) reversed-field pinch (RFP). The CHERS diagnostic measures impurity ion flow and temperature, localized to 2 cm with high time resolution ({approx}100 kHz). A spectral MSE diagnostic has been in use for five years, measuring |B| down to 0.2 T with high precision ({approx}2%) and good time resolution (10 kHz). The Rutherford scattering diagnostic has demonstrated the robustness of this technique for reliable measurement of majority (D) ion temperature, also with high time resolution. MST is a large RFP (R=1.5 m, a=0.52 m) operated at moderate current (I{sub p}{<=}600 kA), with n{sub e} typically (1-2)x10{sup 19} m{sup -3} and T{sub e}, T{sub i}{<=}2 keV. Two compact and reliable diagnostic neutral beams are installed on MST. These beams are short pulse, intense, monoenergetic, and low divergence. The first, a neutral H beam, is used in combination with ultraviolet and visible spectroscopy to make the CHERS and MSE measurements. For CHERS, the C VI line at 343.4 nm is collected by a custom high-throughput double grating spectrometer which simultaneously records both charge-exchange and background emissions. The spectrum is analyzed using a sophisticated model derived from the Atomic Database and Analysis Structure (ADAS) package. The MSE system records the entire H{alpha} Stark spectrum; |B| is derived from the measured splitting of the {pi}{sup +} and {pi}{sup -} manifolds. Measurement of |B| is critical to accurate equilibrium reconstruction in the RFP. The second diagnostic beam is a 20 keV neutral He beam and is used for the Rutherford scattering measurements. A pair of neutral particle analyzers is used to record the energy spectrum of the small-angle Rutherford scattered He atoms.

Den Hartog, D. J.; Craig, D.; Ennis, D. A.; Fiksel, G.; Gangadhara, S.; Holly, D. J.; Reardon, J. C.; Davydenko, V. I.; Ivanov, A. A.; Lizunov, A. A.; O'Mullane, M. G.; Summers, H. P. [Department of Physics, and Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation); University of Strathclyde, Glasgow, G1 1XQ Scotland (United Kingdom)

2006-10-15T23:59:59.000Z

277

TORUS: Theory of Reactions for Unstable iSotopes Annual Continuation and Progress Report Year-2: March 1, 2011 - February 29, 2012  

SciTech Connect (OSTI)

The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.

Arbanas, G; Elster, C; Escher, J; Mukhamedzanov, A; Nunes, F; Thompson, I J

2012-02-24T23:59:59.000Z

278

Investigation of Gas Solid Fluidized Bed Dynamics with Non-Spherical Particles  

SciTech Connect (OSTI)

One of the largest challenges for 21st century is to fulfill global energy demand while also reducing detrimental impacts of energy generation and use on the environment. Gasification is a promising technology to meet the requirement of reduced emissions without compromising performance. Coal gasification is not an incinerating process; rather than burning coal completely a partial combustion takes place in the presence of steam and limited amounts of oxygen. In this controlled environment, a chemical reaction takes place to produce a mixture of clean synthetic gas. Gas-solid fluidized bed is one such type of gasification technology. During gasification, the mixing behavior of solid (coal) and gas and their flow patterns can be very complicated to understand. Many attempts have taken place in laboratory scale to understand bed hydrodynamics with spherical particles though in actual applications with coal, the particles are non-spherical. This issue drove the documented attempt presented here to investigate fluidized bed behavior using different ranges of non-spherical particles, as well as spherical. For this investigation, various parameters are controlled that included particle size, bed height, bed diameter and particle shape. Particles ranged from 355 m to 1180 m, bed diameter varied from 2 cm to 7 cm, two fluidized beds with diameters of 3.4 cm and 12.4 cm, for the spherical and non-spherical shaped particles that were taken into consideration. Pressure drop was measured with increasing superficial gas velocity. The velocity required in order to start to fluidize the particle is called the minimum fluidization velocity, which is one of the most important parameters to design and optimize within a gas-solid fluidized bed. This minimum fluidization velocity was monitored during investigation while observing variables factors and their effect on this velocity. From our investigation, it has been found that minimum fluidization velocity is independent of bed height for both spherical and non-spherical particles. Further, it decrease with decreasing particle size and decreases with decreasing bed diameter. Shadow sizing, a non-intrusive imaging and diagnostic technology, was also used to visualize flow fields inside fluidized beds for both spherical and non- spherical particles and to detect the particle sizes.

Choudhuri, Ahsan

2013-06-30T23:59:59.000Z

279

The torus instability  

E-Print Network [OSTI]

The expansion instability of a toroidal current ring in low-beta magnetized plasma is investigated. Qualitative agreement is obtained with experiments on spheromak expansion and with essential properties of solar coronal mass ejections (CMEs), unifying the two apparently disparate classes of fast and slow CMEs.

Kliem, B

2006-01-01T23:59:59.000Z

280

Brookhaven National Laboratory National Synchrotron Light Source  

E-Print Network [OSTI]

Brookhaven National Laboratory National Synchrotron Light Source Number: Revision: LS-ESH-0027 06 copy of this file is the one on-line in the NSLS ESH website. Before using a printed copy, verify that it is the most current version by checking the document issue date on the NSLS ESH website. BROOKHAVEN NATIONAL

Ohta, Shigemi

Note: This page contains sample records for the topic "national spherical torus" 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

Nevada National Security Site  

Broader source: Energy.gov [DOE]

HISTORYIn 1950, President Truman established what is now known as the Nevada National Security Site (NNSS) to perform nuclear weapons testing activities. In support of national defense initiatives...

282

National Science Bowl Finals  

SciTech Connect (OSTI)

National Science Bowl finals and awards at the National Building Museum in Washington D.C. Monday 5/3/2010

2010-05-03T23:59:59.000Z

283

National Energy Policy (Complete)  

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

Energy Policy May 2001 Report of the National Energy Policy Development Group Reliable, Affordable, and Environmentally Sound Energy for America's Future Report of the National...

284

National Science Bowl Finals  

ScienceCinema (OSTI)

National Science Bowl finals and awards at the National Building Museum in Washington D.C. Monday 5/3/2010

None

2010-09-01T23:59:59.000Z

285

National Nuclear Security Administration  

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

and Related Structures within TA-3 at Los Alamos National Laboratory, Los Alamos, New Mexico U. S. Department of Energy National Nuclear Security Administration Los Alamos Area...

286

Modeling Ion-Exchange Processing With Spherical Resins For Cesium Removal  

SciTech Connect (OSTI)

The spherical Resorcinol-Formaldehyde and hypothetical spherical SuperLig(r) 644 ion-exchange resins are evaluated for cesium removal from radioactive waste solutions. Modeling results show that spherical SuperLig(r) 644 reduces column cycling by 50% for high-potassium solutions. Spherical Resorcinol Formaldehyde performs equally well for the lowest-potassium wastes. Less cycling reduces nitric acid usage during resin elution and sodium addition during resin regeneration, therefore, significantly decreasing life-cycle operational costs. A model assessment of the mechanism behind ''cesium bleed'' is also conducted. When a resin bed is eluted, a relatively small amount of cesium remains within resin particles. Cesium can bleed into otherwise decontaminated product in the next loading cycle. The bleed mechanism is shown to be fully isotherm-controlled vs. mass transfer controlled. Knowledge of residual post-elution cesium level and resin isotherm can be utilized to predict rate of cesium bleed in a mostly non-loaded column. Overall, this work demonstrates the versatility of the ion-exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. This evaluation justifies further development of a spherical form of the SL644 resin.

Hang, T.; Nash, C. A.; Aleman, S. E.

2012-09-19T23:59:59.000Z

287

Non-astigmatic imaging with matched pairs of spherically bent reflectors  

DOE Patents [OSTI]

Arrangements for the point-to-point imaging of a broad spectrum of electromagnetic radiation and ultrasound at large angles of incidence employ matched pairs of spherically bent reflectors to eliminate astigmatic imaging errors. Matched pairs of spherically bent crystals or spherically bent multi-layers are used for X-rays and EUV radiation; and matched pairs of spherically bent mirrors that are appropriate for the type of radiation are used with microwaves, infrared and visible light, or ultrasound. The arrangements encompass the two cases, where the Bragg angle--the complement to the angle of incidence in optics--is between 45.degree. and 90.degree. on both crystals/mirrors or between 0.degree. and 45.degree. on the first crystal/mirror and between 45.degree. and 90.degree. on the second crystal/mirror, where the angles of convergence and divergence are equal. For x-rays and EUV radiation, also the Bragg condition is satisfied on both spherically bent crystals/multi-layers.

Bitter, Manfred Ludwig (Princeton, NJ); Hill, Kenneth Wayne (Plainsboro, NJ); Scott, Steven Douglas (Wellesley, MA); Feder, Russell (Newton, PA); Ko, Jinseok (Cambridge, MA); Rice, John E. (N. Billerica, MA); Ince-Cushman, Alexander Charles (New York, NY); Jones, Frank (Manalapan, NJ)

2012-07-10T23:59:59.000Z

288

The construction of non-spherical models of quasi-relaxed stellar systems  

E-Print Network [OSTI]

Spherical models of collisionless but quasi-relaxed stellar systems have long been studied as a natural framework for the description of globular clusters. Here we consider the construction of self-consistent models under the same physical conditions, but including explicitly the ingredients that lead to departures from spherical symmetry. In particular, we focus on the effects of the tidal field associated with the hosting galaxy. We then take a stellar system on a circular orbit inside a galaxy represented as a "frozen" external field. The equilibrium distribution function is obtained from the one describing the spherical case by replacing the energy integral with the relevant Jacobi integral in the presence of the external tidal field. Then the construction of the model requires the investigation of a singular perturbation problem for an elliptic partial differential equation with a free boundary, for which we provide a method of solution to any desired order, with explicit solutions to two orders. We outline the relevant parameter space, thus opening the way to a systematic study of the properties of a two-parameter family of physically justified non-spherical models of quasi-relaxed stellar systems. The general method developed here can also be used to construct models for which the non-spherical shape is due to internal rotation. Eventually, the models will be a useful tool to investigate whether the shapes of globular clusters are primarily determined by internal rotation, by external tides, or by pressure anisotropy.

G. Bertin; A. L. Varri

2008-08-18T23:59:59.000Z

289

EA-1108: The National Spherical Tokamah Experiment at the Princeton Plasma Physics Laboratory, Plainsboro Township, New Jersey  

Broader source: Energy.gov [DOE]

This EA evaluates the environmental impacts of the proposal to support fusion physics development and technology, by providing an experimental device to investigate the confinement and performance...

290

Criticality and Characteristic Neutronic Analysis of a Transient-State Shockwave in a Pulsed Spherical Gaseous Uranium-Hexafluoride Reactor.  

E-Print Network [OSTI]

??The purpose of this study is to analyze the theoretical criticality of a spherical uranium-hexafluoride reactor with a transient, pulsed shockwave emanating from the center (more)

Boles, Jeremiah

2013-01-01T23:59:59.000Z

291

National Renewable Energy Laboratory  

E-Print Network [OSTI]

National Renewable Energy Laboratory Innovation for Our Energy Future ponsorship Format Reversed Color:White rtical Format Reversed-A ertical Format Reversed-B National Renewable Energy Laboratory National Renewable Energy Laboratory Innovation for Our Energy Future National Renewable Energy Laboratory

292

Probes for measuring fluctuation-induced Maxwell and Reynolds stresses in the edge of the Madison Symmetric Torus reversed field pinch  

SciTech Connect (OSTI)

Several probes have been constructed to measure fluctuation-induced Maxwell and Reynolds stresses in the edge of the Madison Symmetric Torus reversed field pinch (RFP). The magnetic probe is composed of six magnetic pickup coil triplets. The triplets are separated spatially, which allows for local measurements of the Maxwell stress. To measure the plasma flow components for evaluation of the Reynolds stress, we employ a combination of an optical probe [Kuritsyn et al., Rev. Sci. Indrum. 77, 10F112 (2006)] and a Mach probe. The optical probe measures the radial ion flow locally using Doppler spectroscopy. The Mach probe consists of four current collectors biased negatively with respect to a reference tip and allows for measurements of the poloidal and toroidal components of the bulk plasma flow. The stresses are observed to play an important role in the momentum balance in the RFP edge during internal reconnection events.

Kuritsyn, A.; Fiksel, G.; Miller, M. C.; Almagri, A. F.; Reyfman, M.; Sarff, J. S. [Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas and Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2008-10-15T23:59:59.000Z

293

Derivation of nuclear parameters for delayed neutron detector measurements for D-D and D-T plasma operation at the Joint European Torus  

SciTech Connect (OSTI)

The first attempt to calculate the parameters for [sup 238]U and [sup 232]Th used in the analysis of delayed neutron counter measurements of the total neutron yield from deuterium-tritium (D-T) plasmas is described. The nuclear theory of systematics is employed, together with nuclear data from the literature. As a check on the methods used, the delayed neutron parameters were also calculated for deuterium-deuterium plasma conditions; the resulting neutron yields agreed within [+-]7% with the results obtained using the experimentally calibrated delayed neutron counter assemblies. After the calculations were completed, the first D-T plasma experiment was performed at the Joint European Torus (JET). Delayed neutron measurements were made using [sup 232]Th samples. The calculated delayed neutron parameters gave neutron yields that agreed within [+-]8% with those obtained with conventional activation methods, using iron and silicon samples. 30 refs., 5 figs., 8 tabs.

Angelone, M. (JET Joint Undertaking Abingdon, Oxon (United Kingdom))

1993-08-01T23:59:59.000Z

294

Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source  

SciTech Connect (OSTI)

A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (23) 10{sup 19} m{sup ?3} to 1 10{sup 19} m{sup ?3}. Deuterium spheromak formation is possible with density as low as 2 10{sup 18} m{sup ?3}. The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reduction of breakdown density is presented.

Hossack, Aaron C.; Jarboe, Thomas R.; Victor, Brian S. [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States)] [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States); Firman, Taylor; Prager, James R.; Ziemba, Timothy [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States)] [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States); Wrobel, Jonathan S. [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)] [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)

2013-10-15T23:59:59.000Z

295

Weak-Field Spherically Symmetric Solutions in $f(T)$ gravity  

E-Print Network [OSTI]

We study weak-field solutions having spherical symmetry in $f(T)$ gravity; to this end, we solve the field equations for a non diagonal tetrad, starting from Lagrangian in the form $f(T)=T+\\alpha T^{n}$, where $\\alpha$ is a small constant, parameterizing the departure of the theory from GR. We show that the classical spherically symmetric solutions of GR, i.e. the Schwarzschild and Schwarzschild-de Sitter solutions, are perturbed by terms in the form $\\propto r^{2-2n}$ and discuss the impact of these perturbations in observational tests.

Ruggiero, Matteo Luca

2015-01-01T23:59:59.000Z

296

Approximation method for a spherical bound system in the quantum plasma  

SciTech Connect (OSTI)

A system of quantum hydrodynamic equations has been used for investigating the dielectric tensor and dispersion equation of a semiconductor as a quantum magnetized plasma. Dispersion relations and their modifications due to quantum effects are derived for both longitudinal and transverse waves. The number of states and energy levels are analytically estimated for a spherical bound system embedded in a semiconductor quantum plasma. The results show that longitudinal waves decay rapidly and do not interact with the spherical bound system. The energy shifts caused by the spin-orbit interaction and the Zeeman effect are calculated.

Mehramiz, A.; Sobhanian, S. [Department of Atomic and Molecular Physics, Faculty of Physics, University of Tabriz, East Azerbaijan 51664 (Iran, Islamic Republic of); Mahmoodi, J. [Department of Physics, Faculty of Science, University of Qom, P.O. Box 3716146611, Qom (Iran, Islamic Republic of)

2010-08-15T23:59:59.000Z

297

Mojave National Preserve Joshua Tree National Park  

E-Print Network [OSTI]

Forest (SBNF) Angeles National Forest (ANF) Cleveland National Forest (CNF) CNF CNF SBNF ANF CACA 049111°0'0"N 34°0'0"N 34°0'0"N 33°0'0"N 33°0'0"N California Desert Conservation Area BLM Solar Energy Project Contingent Corridor Deleted Corridor Land Status BLM National Park Service Forest Service Military USFWS

Laughlin, Robert B.

298

Sandia National Laboratories: National Rotor Testbed Functional...  

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

of the National Rotor Testbed: An Aeroelastically Relevant Research-Scale Wind Turbine Rotor." Approximately 60 researchers from various institutions and countries attended...

299

Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models with Lagrangian Coordinates  

E-Print Network [OSTI]

Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models blocks and splits a block as refinements occur. The current functionality provides automatic generation the use of a longer time step. We have developed an Adaptive Mesh Refinement (AMR) dynamical core

Jablonowski, Christiane

300

Adiabatic Quasi-Spherical Compressions Driven by Magnetic Pressure for Inertial Confinement Fusion  

SciTech Connect (OSTI)

The magnetic implosion of a high-Z quasi-spherical shell filled with DT fuel by the 20-MA Z accelerator can heat the fuel to near-ignition temperature. The attainable implosion velocity on Z, 13-cm/{micro}s, is fast enough that thermal losses from the fuel to the shell are small. The high-Z shell traps radiation losses from the fuel, and the fuel reaches a high enough density to reabsorb the trapped radiation. The implosion is then nearly adiabatic. In this case the temperature of the fuel increases as the square of the convergence. The initial temperature of the fuel is set by the heating of an ion acoustic wave to be about 200-eV after a convergence of 4. To reach the ignition temperature of 5-keV an additional convergence of 5 is required. The implosion dynamics of the quasi-spherical implosion is modeled with the 2-D radiation hydrodynamic code LASNEX. LASNEX shows an 8-mm diameter quasi-spherical tungsten shell on Z driving 6-atmospheres of DT fuel nearly to ignition at 3.5-keV with a convergence of 20. The convergence is limited by mass flow along the surface of the quasi-spherical shell. With a convergence of 20 the final spot size is 400-{micro}m in diameter.

NASH,THOMAS J.

2000-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

On the extraction of laminar flame speed and Markstein length from outwardly propagating spherical flames  

SciTech Connect (OSTI)

Large discrepancies among the laminar flame speeds and Markstein lengths of methane/air mixtures measured by different researchers using the same constant-pressure spherical flame method are observed. As an effort to reduce these discrepancies, one linear model (LM, the stretched flame speed changes linearly with the stretch rate) and two non-linear models (NM I and NM II, the stretched flame speed changes non-linearly with the stretch rate) for extracting the laminar flame speed and Markstein length from propagating spherical flames are investigated. The accuracy and performance of the LM, NM I, and NM II are found to strongly depend on the Lewis number. It is demonstrated that NM I is the most accurate for mixtures with large Lewis number (positive Markstein length) while NM II is the most accurate for mixtures with small Lewis number (negative Markstein length). Therefore, in order to get accurate laminar flame speed and Markstein length from spherical flame experiments, different non-linear models should be used for different mixtures. The validity of the theoretical results is further demonstrated by numerical and experimental studies. The results of this study can be used directly in spherical flame experiments measuring the laminar flame speed and Markstein length. (author)

Chen, Zheng [State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871 (China)

2011-02-15T23:59:59.000Z

302

Local Casimir Energies for a Thin Spherical Shell Ines Cavero-Pelaez,  

E-Print Network [OSTI]

Local Casimir Energies for a Thin Spherical Shell In´es Cavero-Pel´aez, Kimball A. Milton. In the limit of zero thickness, an ideal -function shell is recovered. The behavior of the energy density of surface divergences and on the energy contained within the shell, are obtained in the weak coupling limit

Milton, Kim

303

Phenomenological study of parabolic and spherical indentation of elastic-ideally plastic material  

E-Print Network [OSTI]

Phenomenological study of parabolic and spherical indentation of elastic-ideally plastic material O ideally plastic materials was carried out by using precise results of finite elements calculations behaviour is found. Two elastic-plastic regimes and two plastic regimes are observed for materials of very

Paris-Sud XI, Université de

304

Pervaporation of Emulsion Droplets for the Templated Assembly of Spherical Particles: A Population Balance Model  

E-Print Network [OSTI]

, but are immiscible with each other as the solvent volume decreases.4­9 Water-in-oil emulsions, where the water, evaporation, population balance, pervaporation, mathematical modeling, transport Introduction The emulsionPervaporation of Emulsion Droplets for the Templated Assembly of Spherical Particles: A Population

Braatz, Richard D.

305

An Efficient Approach for Optical Radiative Transfer Tomography using the Spherical Harmonics Discrete Ordinates Method  

E-Print Network [OSTI]

This paper introduces a method to preform optical tomography, using 3D radiative transfer as the forward model. We use an iterative approach predicated on the Spherical Harmonics Discrete Ordinates Method (SHDOM) to solve the optimization problem in a scalable manner. We illustrate with an application in remote sensing of a cloudy atmosphere.

Levis, Aviad; Aides, Amit; Davis, Anthony B

2015-01-01T23:59:59.000Z

306

Scroll waves in spherical shell geometries Francisco Chavez and Raymond Kapral  

E-Print Network [OSTI]

Scroll waves in spherical shell geometries Francisco Cha´vez and Raymond Kapral Chemical Physics Received 25 April 2001; accepted 21 July 2001; published 4 October 2001 The evolution of scroll waves. The motion of scroll wave filaments that are the locii of phaseless points in the medium and organize

Glass, Leon

307

On the critical flame radius and minimum ignition energy for spherical flame initiation  

SciTech Connect (OSTI)

Spherical flame initiation from an ignition kernel is studied theoretically and numerically using different fuel/oxygen/helium/argon mixtures (fuel: hydrogen, methane, and propane). The emphasis is placed on investigating the critical flame radius controlling spherical flame initiation and its correlation with the minimum ignition energy. It is found that the critical flame radius is different from the flame thickness and the flame ball radius and that their relationship depends strongly on the Lewis number. Three different flame regimes in terms of the Lewis number are observed and a new criterion for the critical flame radius is introduced. For mixtures with Lewis number larger than a critical Lewis number above unity, the critical flame radius is smaller than the flame ball radius but larger than the flame thickness. As a result, the minimum ignition energy can be substantially over-predicted (under-predicted) based on the flame ball radius (the flame thickness). The results also show that the minimum ignition energy for successful spherical flame initiation is proportional to the cube of the critical flame radius. Furthermore, preferential diffusion of heat and mass (i.e. the Lewis number effect) is found to play an important role in both spherical flame initiation and flame kernel evolution after ignition. It is shown that the critical flame radius and the minimum ignition energy increase significantly with the Lewis number. Therefore, for transportation fuels with large Lewis numbers, blending of small molecule fuels or thermal and catalytic cracking will significantly reduce the minimum ignition energy.

Chen, Zheng; Burke, M. P.; Ju, Yiguang

2011-01-01T23:59:59.000Z

308

CALTECH ASCI TECHNICAL REPORT 129 On Velocity Structure Functions and the Spherical Vortex Model for  

E-Print Network [OSTI]

the stretched-spiral vortex has been suc- cessfully applied to the calculation of the energy spectrum,6 and some for larger scales is perhaps questionable. Most quantitative vortex-based models have utilized tube and sheetCALTECH ASCI TECHNICAL REPORT 129 On Velocity Structure Functions and the Spherical Vortex Model

Barr, Al

309

Analysis of grid imprinting on geodesic spherical icosahedral grids Pedro S. Peixoto, Saulo R. M. Barros  

E-Print Network [OSTI]

Analysis of grid imprinting on geodesic spherical icosahedral grids Pedro S. Peixoto, Saulo R. M-090 S~ao Paulo, Brazil Abstract Numerical grid imprinting errors have often been observed in global atmospheric models on icosahedral grids. In this paper we analyse the sources of grid imprinting error related

310

Spherically symmetric droplet combustion of three and four component miscible mixtures as surrogates for  

E-Print Network [OSTI]

.48/7.28/22.83, respectively, were previously shown to replicate certain gas phase combustion properties of JetSpherically symmetric droplet combustion of three and four component miscible mixtures This study examines the droplet combustion characteristics of three and four component miscible liquid

Walter, M.Todd

311

1:17 p.m. August 25, 2012 [Macdonald] Remarks on Macdonald's book on p-adic spherical functions  

E-Print Network [OSTI]

1:17 p.m. August 25, 2012 [Macdonald] Remarks on Macdonald's book on p-adic spherical functions Bill Casselman University of British Columbia cass@math.ubc.ca When Ian Macdonald's book Spherical of some of Macdonald's themes I shall necessarily restrict myself only to things closely related to them

Casselman, William

312

HigHligHts and BreaktHrougHs Pauling's rules, in a world of non-spherical atoms  

E-Print Network [OSTI]

HigHligHts and BreaktHrougHs Pauling's rules, in a world of non-spherical atoms roBert t. downs tenet of Pauling's Rules, which is that atoms are spheres of a single fixed size.Their analysis provides, explains the older ones. Keywords: Electron density distribution, Paulings rules, non-spherical atoms Jerry

Downs, Robert T.

313

The spherically symmetric droplet burning characteristics of Jet-A and biofuels derived from camelina and tallow  

E-Print Network [OSTI]

The spherically symmetric droplet burning characteristics of Jet-A and biofuels derived from the biofuels due to its higher aromatic content. " Droplet burning rates of camelina and tallow HRJ fuel Available online 1 March 2013 Keywords: Alternative jet fuel Hydroprocessed biofuel Spherically symmetric

Walter, M.Todd

314

Brookhaven National Laboratory National Synchrotron Light Source  

E-Print Network [OSTI]

Brookhaven National Laboratory National Synchrotron Light Source Number: Revision: LS-ESH-0026 4 (ANSI) Hazard Class 3B and 4 laser systems must be documented, reviewed, and approved through use) CrystaLaser Compact Solid State Laser (Class 3B) Location: All four lasers are located in the U2A

Ohta, Shigemi

315

Nonlinear coupling of tearing fluctuations in the Madison Symmetric Torus<atother>@f|</atother>  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNationalNewportBig Eddy ArcheologicalSolarto

316

SUZAKU VIEW OF THE SWIFT/BAT ACTIVE GALACTIC NUCLEI. V. TORUS STRUCTURE OF TWO LUMINOUS RADIO-LOUD ACTIVE GALACTIC NUCLEI (3C 206 AND PKS 0707-35)  

SciTech Connect (OSTI)

We present the results from broadband X-ray spectral analysis of 3C 206 and PKS 0707-35 with Suzaku and Swift/BAT, two of the most luminous unobscured and obscured radio-loud active galactic nuclei (AGNs) with hard X-ray luminosities of 10{sup 45.5} erg s{sup -1} and 10{sup 44.9} erg s{sup -1} (14-195 keV), respectively. Based on the radio core luminosity, we estimate that the X-ray spectrum of 3C 206 contains a significant ({approx}60% in the 14-195 keV band) contribution from the jet, while it is negligible in PKS 0707-35. We can successfully model the spectra with the jet component (for 3C 206), the transmitted emission, and two reflection components from the torus and the accretion disk. The reflection strengths from the torus are found to be R{sub torus}({identical_to} {Omega}/2{pi}) = 0.29 {+-} 0.18 and 0.41 {+-} 0.18 for 3C 206 and PKS 0707-35, respectively, which are smaller than those in typical Seyfert galaxies. Utilizing the torus model by Ikeda et al., we quantify the relation between the half-opening angle of a torus ({theta}{sub oa}) and the equivalent width of an iron-K line. The observed equivalent width of 3C 206, < 71 eV, constrains the column density in the equatorial plane to N{sub H}{sup eq} <10{sup 23} cm{sup -2}, or the half-opening angle to {theta}{sub oa} > 80 Degree-Sign if N{sub H}{sup eq} =10{sup 24} cm{sup -2} is assumed. That of PKS 0707-35, 72 {+-} 36 eV, is consistent with N{sub H}{sup eq} {approx}10{sup 23} cm{sup -2}. Our results suggest that the tori in luminous radio-loud AGNs are only poorly developed. The trend is similar to that seen in radio-quiet AGNs, implying that the torus structure is not different between AGNs with jets and without jets.

Tazaki, Fumie; Ueda, Yoshihiro [Department of Astronomy, Kyoto University, Kyoto 606-8502 (Japan); Terashima, Yuichi [Department of Physics, Ehime University, Matsuyama 790-8577 (Japan); Mushotzky, Richard F.; Tombesi, Francesco [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)

2013-07-20T23:59:59.000Z

317

Argonne National Laboratory's Nondestructive  

E-Print Network [OSTI]

Argonne National Laboratory's Nondestructive Evaluation Technologies NDE #12;Over45yearsexperienceinNondestructiveEvaluation... Argonne National Laboratory's world-renowned researchers have a proven the safe operationof advanced nuclear reactors. Argonne's World-Class Nondestructive Evaluation

Kemner, Ken

318

National Nuclear Security Administration  

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

FROM: SUBJECT: USIUK Memorandum of Understanding between National Nuclear Security Administration's (NNSA) Associate Administrator for Defense Nuclear Security (AADNS)...

319

National Hydropower Map  

Broader source: Energy.gov [DOE]

High-resolution map produced by Oak Ridge National Laboratory showing hydropower resources throughout the United States.

320

National Nuclear Security Administration Los Alamos National  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contractedLawrence National

Note: This page contains sample records for the topic "national spherical torus" 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

National Supplemental Screening Program | Argonne National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos(SC)National

322

NATIONAL HYDROGEN ENERGY ROADMAP  

E-Print Network [OSTI]

NATIONAL HYDROGEN ENERGY ROADMAP NATIONAL HYDROGEN ENERGY ROADMAP . . Toward a More Secure and Cleaner Energy Future for America Based on the results of the National Hydrogen Energy Roadmap Workshop to make it a reality. This Roadmap provides a framework that can make a hydrogen economy a reality

323

Brookhaven National Laboratory National Synchrotron Light Source  

E-Print Network [OSTI]

CHARACTERISTICS Laser Type (Argon, CO2, etc) Wavelengths ANSI Class Maximum Power of Energy/Pulse Pulse Length. American National Standards Institute (ANSI) Standard for Safe Use of Lasers; (ANSI Z136.1-2000) Laser

Ohta, Shigemi

324

Distribution of ion current density on a rotating spherical cap substrate during ion-assisted deposition  

SciTech Connect (OSTI)

The uniformity of ion density is critical for applications relying on the ion assisted deposition technique for the fabrication of the high quality thin films. The authors propose and describe here a method allowing one to calculate the ion density distribution on spherical substrate holders under stationary and rotating conditions for different positions of the ion source. The ion beam shape was approximated by a cos{sup n} function, and the ion current density was represented by a function inversely proportional to the distance from the ion source in accordance with our experimental results. As an example, a calculation of the current density distribution on the spherical cap substrate was performed for a broad beam ion source operated with an anode current of 3?A. The authors propose an approach for process optimization with respect to the ion source position and its inclination, in terms of uniformity and absolute value of the ion current density.

Marushka, Viktor; Zabeida, Oleg, E-mail: oleg.zabeida@polymtl.ca; Martinu, Ludvik [Engineering Physics Department, Polytechnique Montral, P.O. Box 6079, Downtown station, Montreal, Quebec H3C 3A7 (Canada)

2014-11-01T23:59:59.000Z

325

The reduced phase space of spherically symmetric Einstein-Maxwell theory including a cosmological constant  

E-Print Network [OSTI]

We extend here the canonical treatment of spherically symmetric (quantum) gravity to the most simple matter coupling, namely spherically symmetric Maxwell theory with or without a cosmological constant. The quantization is based on the reduced phase space which is coordinatized by the mass and the electric charge as well as their canonically conjugate momenta, whose geometrical interpretation is explored. The dimension of the reduced phase space depends on the topology chosen, quite similar to the case of pure (2+1) gravity. We investigate several conceptual and technical details that might be of interest for full (3+1) gravity. We use the new canonical variables introduced by Ashtekar, which simplifies the analysis tremendously.

T. Thiemann

1999-10-04T23:59:59.000Z

326

Reduced Phase Space Quantization of spherically symmetric Einstein-Maxwell-Theory including a cosmological constant  

E-Print Network [OSTI]

We present here the canonical treatment of spherically symmetric (quantum) gravity coupled to spherically symmetric Maxwell theory with or without a cosmological constant. The quantization is based on the reduced phase space which is coordinatized by the mass and the electric charge as well as their canonically conjugate momenta, whose geometrical interpretation is explored. The dimension of the reduced phase space depends on the topology chosen, quite similar to the case of pure (2+1) gravity. We also compare the reduced phase space quantization to the algebraic quantization. Altogether, we observe that the present model serves as an interesting testing ground for full (3+1) gravity. We use the new canonical variables introduced by Ashtekar which simplifies the analysis tremendously.

T. Thiemann

1999-10-04T23:59:59.000Z

327

Light-emitting diode spherical packages: an equation for the light transmission efficiency  

E-Print Network [OSTI]

Virtually all light-emitting diodes (LEDs) are encapsulated with a transparent epoxy or silicone-gel. In this paper we analyze the optical efficiency of spherical encapsulants. We develop a quasi-radiometric equation for the light transmission efficiency, which incorporates some ideas of Monte-Carlo ray tracing into the context of radiometry. The approach includes the extended source nature of the LED chip, and the chip radiance distribution. The equation is an explicit function of the size and the refractive index of the package, and also of several chip parameters such as shape, size, radiance, and location inside the package. To illustrate the use of this equation, we analyze several packaging configurations of practical interest; for example, a hemispherical dome with multiple chips, a flat encapsulation as a special case of the spherical package, and approximate calculations of an encapsulant with a photonic crystal LED or with a photonic quasi crystal LED. These calculations are compared with Monte-Carl...

Moreno, Ivan; Avendano-Alejo, Maximino; 10.1364/AO.49.000012

2011-01-01T23:59:59.000Z

328

A special exact spherically symmetric solution in f(T) gravity theories  

E-Print Network [OSTI]

A non-diagonal spherically symmetric tetrad field, involving four unknown functions of radial coordinate $r$, is applied to the equations of motion of f(T) gravity theory. A special exact vacuum solution with one constant of integration is obtained. The scalar torsion related to this special solution vanishes. To understand the physical meaning of the constant of integration we calculate the energy associated with this solution and show how it is related to the gravitational mass of the system.

G. G. L. Nashed

2015-02-17T23:59:59.000Z

329

Casimir energy for self-interacting scalar field in a spherical shell  

E-Print Network [OSTI]

In this paper we calculate the Casimir energy for spherical shell with massless self-interacting scalar filed which satisfying Dirichlet boundary conditions on the shell. Using zeta function regularization and heat kernel coefficients we obtain the divergent contributions inside and outside of Casimir energy. The effect of self-interacting term is similar with existing of mass for filed. In this case some divergent part arises. Using the renormalization procedure of bag model we can cancel these divergent parts.

M. R. Setare; R. Mansouri

2002-01-27T23:59:59.000Z

330

A special exact spherically symmetric solution in f(T) gravity theories  

E-Print Network [OSTI]

A non-diagonal spherically symmetric tetrad field, involving four unknown functions of radial coordinate $r$, is applied to the equations of motion of f(T) gravity theory. A special exact vacuum solution with one constant of integration is obtained. The scalar torsion related to this special solution vanishes. To understand the physical meaning of the constant of integration we calculate the energy associated with this solution and show how it is related to the gravitational mass of the system.

Nashed, G G L

2015-01-01T23:59:59.000Z

331

Ionic Asymmetry and Solvent Excluded Volume Effects on Spherical Electric Double Layers: A Density Functional Approach  

SciTech Connect (OSTI)

In this article we present a classical density functional theory for electrical double layers of spherical macroions that extends the capabilities of conventional approaches by accounting for electrostatic ion correlations, size asymmetry and excluded volume effects. The approach is based on a recent approximation introduced by Hansen-Goos and Roth for the hard sphere excess free energy of inhomogeneous fluids (J. Chem. Phys. 124, 154506). It accounts for the proper and efficient description of the effects of ionic asymmetry and solvent excluded volume, especially at high ion concentrations and size asymmetry ratios including those observed in experimental studies. Additionally, we utilize a leading functional Taylor expansion approximation of the ion density profiles. In addition, we use the Mean Spherical Approximation for multi-component charged hard sphere fluids to account for the electrostatic ion correlation effects. These approximations are implemented in our theoretical formulation into a suitable decomposition of the excess free energy which plays a key role in capturing the complex interplay between charge correlations and excluded volume effects. We perform Monte Carlo simulations in various scenarios to validate the proposed approach, obtaining a good compromise between accuracy and computational cost. We use the proposed computational approach to study the effects of ion size, ion size asymmetry and solvent excluded volume on the ion profiles, integrated charge, mean electrostatic potential, and ionic coordination number around spherical macroions in various electrolyte mixtures. Our results show that both solvent hard sphere diameter and density play a dominant role in the distribution of ions around spherical macroions, mainly for experimental water molarity and size values where the counterion distribution is characterized by a tight binding to the macroion, similar to that predicted by the Stern model.

Medasani, Bharat; Ovanesyan, Zaven; Thomas, Dennis G.; Sushko, Maria L.; Marucho, Marcelo

2014-05-29T23:59:59.000Z

332

Method of determining elastic and plastic mechanical properties of ceramic materials using spherical indenters  

DOE Patents [OSTI]

The invention pertains a method of determining elastic and plastic mechanical properties of ceramics, intermetallics, metals, plastics and other hard, brittle materials which fracture prior to plastically deforming when loads are applied. Elastic and plastic mechanical properties of ceramic materials are determined using spherical indenters. The method is most useful for measuring and calculating the plastic and elastic deformation of hard, brittle materials with low values of elastic modulus to hardness.

Adler, Thomas A. (Corvallis, OR)

1996-01-01T23:59:59.000Z

333

Role of Modified Chaplygin Gas as a Dark Energy Model in Collapsing Spherically Symmetric Cloud  

E-Print Network [OSTI]

In this work, gravitational collapse of a spherical cloud, consists of both dark matter and dark energy in the form of modified Chaplygin gas is studied. It is found that dark energy alone in the form of modified Chaplygin gas forms black hole. Also when both components of the fluid are present then the collapse favors the formation of black hole in cases the dark energy dominates over dark matter. The conclusion is totally opposite to the usually known results.

Ujjal Debnath; Subenoy Chakraborty

2006-01-12T23:59:59.000Z

334

Why Professor Richard Feynman was upset solving the Laplace equation for spherical waves?  

E-Print Network [OSTI]

We take attention to the singular behavior of the Laplace operator in spherical coordinates, which was established in our earlier work. This singularity has many non-trivial consequences. In this article we consider only the simplest ones, which are connected to the solution of Laplace equation in Feynman classical books and Lectures. Feynman was upset looking in his derived solutions, which have a fictitious singular behavior at the origin. We show how these inconsistencies can be avoided.

Anzor Khelashvili; Teimuraz Nadareishvili

2013-02-04T23:59:59.000Z

335

Decay of Dirac Massive Hair in the Background of Spherical Black Hole  

E-Print Network [OSTI]

The intermediate and late-time behaviour of massive Dirac hair in the static spherically symmetric black hole spacetime was studied. It was revealed that the intermediate asymptotic pattern of decay of massive Dirac spinor hair is dependent on the mass of the field under consideration as well as the multiple number of the wave mode. The long-lived oscillatory tail observed at timelike infinity in the considered background decays slowly as t^{-5/6}.

Rafa? Moderski; Marek Rogatko

2008-05-06T23:59:59.000Z

336

Spherically symmetric self-similar solutions and their astrophysical and cosmological applications  

E-Print Network [OSTI]

We discuss spherically symmetric perfect fluid solutions of Einstein's equations which have equation of state ($p=\\alpha \\mu$) and which are self-similar in the sense that all dimensionless variables depend only upon $z\\equiv r/t$. For each value of $\\alpha$, such solutions are described by two parameters and have now been completely classified. There is a 1-parameter family of solutions asymptotic to the flat Friedmann model at large values of z. These represent either black holes or density perturbations which grow as fast as the particle horizon; the underdense solutions may be relevant to the existence of large-scale cosmic voids. There is also a 1-parameter family of solutions asymptotic to a self-similar Kantowski-Sachs model at large z. These are probably only physically realistic for $-11/5$, there is a family of solutions which are asymptotically Minkowski. These asymptote either to infinite z, in which case they are described by one parameter, or to a finite value of z, in which case they are described by two parameters and this includes the ``critical'' solution for $\\alpha >0.28$. We discuss the stability of spherically symmetric similarity solutions to more general (non-self-similar) spherically symmetric perturbations.

B. J. Carr

2000-03-02T23:59:59.000Z

337

A hyper-spherical adaptive sparse-grid method for high-dimensional discontinuity detection  

SciTech Connect (OSTI)

This work proposes and analyzes a hyper-spherical adaptive hi- erarchical sparse-grid method for detecting jump discontinuities of functions in high-dimensional spaces is proposed. The method is motivated by the the- oretical and computational inefficiencies of well-known adaptive sparse-grid methods for discontinuity detection. Our novel approach constructs a func- tion representation of the discontinuity hyper-surface of an N-dimensional dis- continuous quantity of interest, by virtue of a hyper-spherical transformation. Then, a sparse-grid approximation of the transformed function is built in the hyper-spherical coordinate system, whose value at each point is estimated by solving a one-dimensional discontinuity detection problem. Due to the smooth- ness of the hyper-surface, the new technique can identify jump discontinuities with significantly reduced computational cost, compared to existing methods. Moreover, hierarchical acceleration techniques are also incorporated to further reduce the overall complexity. Rigorous error estimates and complexity anal- yses of the new method are provided as are several numerical examples that illustrate the effectiveness of the approach.

Zhang, Guannan [ORNL; Webster, Clayton G [ORNL; Gunzburger, Max D [ORNL; Burkardt, John V [ORNL

2014-03-01T23:59:59.000Z

338

First X-ray-Based Statistical Tests for Clumpy-Torus Models: Eclipse Events from 230 Years of Monitoring of Seyfert AGN  

E-Print Network [OSTI]

We present an analysis of multi-timescale variability in line-of-sight X-ray absorbing gas as a function of optical classification in a large sample of Seyfert AGN to derive the first X-ray statistical constraints for clumpy-torus models. We systematically search for discrete absorption events in the vast archive of RXTE monitoring of dozens of nearby type I and Compton-thin type II AGN. We are sensitive to discrete absorption events due to clouds of full-covering, neutral or mildly ionized gas with columns <~ 10^(22-25) cm^-2 transiting the line of sight. We detect 12 eclipse events in 8 objects, roughly tripling the number previously published from this archive. Peak column densities span ~ 4-26 x 10^22 cm^-2. Event durations span hours to months. The column density profile for an eclipsing cloud in NGC 3783 is doubly spiked, possibly indicating a cloud that is being tidally sheared. We infer the clouds' distances from the black hole to span ~0.3 -140 x 10^4 R_g. In seven objects, the clouds' distances a...

Markowitz, Alex; Nikutta, Robert

2014-01-01T23:59:59.000Z

339

On the LINER nuclear obscuration, Compton-thickness and the existence of the dusty torus; Clues from Spitzer/IRS spectra  

E-Print Network [OSTI]

Most of the optically classified low ionisation narrow emission-line regions (LINERs) nuclei host an active galactic nuclei (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. The aims of this work are to study at mid-infrared (mid-IR) (1) the Compton-thick nature of LINERs; and (2) the disappearance of the dusty torus in LINERs predicted from theoretical arguments. We have compiled all the available low spectral resolution mid-IR spectra of LINERs from the IRS/Spitzer (40 LINERs). We have complemented this sample with Spitzer/IRS spectra of PGQSOs, S1s, S2s, and SBs nuclei. We have studied the AGN versus the starburst content in our sample using different indicators: the EW(PAH 6.2um), the strength of the silicate feature at 9.7um, and the steepness of the mid-IR spectra. In 25 out of the 40 LINERs (i.e., 62.5%) the mid-IR spectra are not SB-dominated, similar to the comparison S2 sample (67.7%). The average spectra of both SB-dominated LINERs and S2s are very similar t...

Gonzalez-Martin, O; Marquez, I; Rodrguez-Espinosa, J M; Acosta-Pulido, J A; Ramos-Almeida, C; Dultzin, D; Hernandez-Garcia, L; Ruschel-Dutra, D; Alonso-Herrero, A

2015-01-01T23:59:59.000Z

340

Assessment of radial image distortion and spherical aberration on three-dimensional synthetic aperture particle image velocimetry measurements  

E-Print Network [OSTI]

This thesis presents a numerical study of the effects of radial image distortion and spherical aberration on reconstruction quality of synthetic aperture particle image velocimetry (SAPIV) measurements. A simulated SAPIV ...

Kubaczyk, Daniel Mark

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Los Alamos National Laboratory  

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

23, 2013-Nearly 400 Los Alamos National Laboratory employees on 47 teams received Pollution Prevention awards for protecting the environment and saving taxpayers more than 8...

342

National Day of Remembrance  

SciTech Connect (OSTI)

Ames Laboratory observed the National Day of Remembrance for weapons workers from the Cold War era with a ceremony held Oct. 27, 2009 at the Ames Public Library.

None

2010-01-01T23:59:59.000Z

343

National Energy Awareness Month  

Broader source: Energy.gov [DOE]

October is National Energy Awareness Month. It's also a chance to talk about our countrys energy security and its clean energy future.

344

Idaho National Laboratory Facilities  

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

National Scientific User Facility Center for Advanced Energy Studies Light Water Reactor Sustainability Idaho Regional Optical Network LDRD Next Generation Nuclear Plant Docs...

345

Idaho National Laboratory Newsroom  

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

list of common INL acronyms and abbreviations. Page Contact Information: Nicole Stricker (208) 526-5955 Email Contact Feature Story Counting the ways Idaho National...

346

2012 National Electricity Forum  

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

or direct us to appropriate source materials.) To the extent that you believe your region has conditional congestion of national significance, what are the factors or...

347

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

the Earth's Surface. The second virtual classroom to the student was presented by Tommy Smith from Lawrence Livermore National Laboratory on various sources of energy, its use and...

348

National Nuclear Security Administration  

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

Project Reviews, etc., except those specifically reserved for the Administrator for the National Nuclear Security Administration and the Deputy Secretary. cc: Mike Hickman. NA-Stl...

349

National Cybersecurity Awareness Month  

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

National Cybersecurity Awareness Month (NCSAM) October 2013 Every October, the Department of Energy joins the Department of Homeland Security (DHS) and others across the country...

350

National Laboratory Photovoltaics Research  

Broader source: Energy.gov [DOE]

DOE supports photovoltaic (PV) research and development and facilities at its national laboratories to accelerate progress toward achieving the SunShot Initiative's technological and economic...

351

Los Alamos National Laboratory  

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

this tenth member of our National Centers for Systems Biology program," said James Anderson, who oversees systems biology awards at NIGMS. "The new center will apply...

352

national security campus | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational NuclearhasAdministration goSecuritycdns ||fors| National

353

National Postdoctoral Association | Argonne National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy Loginof Energy National

354

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos in Space

355

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos in

356

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos inDARHT: A

357

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos inDARHT:

358

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos inDARHT:A

359

National Security Science | Los National Alamos Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNationalLos Alamos

360

National Park Service- Yellowstone National Park, Wyoming  

Broader source: Energy.gov [DOE]

Yellowstone National Park, Wyoming, has many historical sites within its boundaries. One of these is the Lamar Buffalo Ranch, a ranch that was set up in the early 1900s to breed buffalo for replacement stock within the park during a time when their numbers were very low. The ranch buildings are currently being used by the Yellowstone Association Institute for ecology classes.

Note: This page contains sample records for the topic "national spherical torus" 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

National Research Council Canada  

E-Print Network [OSTI]

National Research Council Canada Institute for Information Technology Conseil national de recherches Canada Institut de technologie de l'information Determining Internet Users' Values for Private in The Second Annual Conference on Privacy, Security and Trust (PST'04). Fredericton, New Brunswick, Canada

Fleming, Michael W.

362

INDIAN NATIONAL SCIENCE ACADEMY  

E-Print Network [OSTI]

INDIAN NATIONAL SCIENCE ACADEMY Science academies play a crucial role in promoting, recognizing and bring out proceedings and monographs. The academies promote public awareness and understanding the country. In this section the growth of the Indian National Science Academy and its functions

Srinivasan, N.

363

National Energy Software Center  

SciTech Connect (OSTI)

A short introduction is given to the services of the National Energy Software Library at the Argonne National Laboratory. The objectives, history, and software collection of the center are presented. Information on ordering from the software collection of the library is also included. 4 refs., 3 tabs. (DWL)

Eyberger, L.R.

1986-01-01T23:59:59.000Z

364

National Osteoporosis Prevention Month  

E-Print Network [OSTI]

MAY National Osteoporosis Prevention Month JUNE National Dairy Month Texas AgriLife Extension - Bone Health Power Point # P4-1 Eat Smart for Bone Health # P4-2 Osteoporosis Disease Statistics # P4-3 Osteoporosis = Porous Bones # P4-4 Risk Factors # P4-5 Risk Factors (continued) # P4-6 Steps to Prevention # P4

365

The National Cancer Institute,  

E-Print Network [OSTI]

The National Cancer Institute, International Cancer Information Center Bldg. 82, Rm 123 Bethesda, MD 20892 The National Cancer Institute (NCI) is part of the Federal Government. NCI coordinates the government's cancer research program. It is the largest of the 17 biomedical research institutes and centers

366

Dale M. Meade 2002 Fusion Summer Study  

E-Print Network [OSTI]

and Technolgy Feasibility Electric Power Feasibility Economic Feasibility Spherical Torus, RFP Spheromak, FRC Torus, RFP Spheromak, FRC, MTF Three Large Tokamaks JT-60 U JET TFTR Several Large Facilities FIRE KSTAR

367

National Institutes of Health National Institute of Mental Health  

E-Print Network [OSTI]

National Institutes of Health National Institute of Mental Health Department of Health and HumanNational Institute of Mental Health Division of Intramural Research Programs http://intramural.nimh.nih.gov/ [NIMH of Fellowship Training] National Institutes of Health National Institute of Mental Health Department of Health

Baker, Chris I.

368

Spherical Shell Cosmological Model and Uniformity of Cosmic Microwave Background Radiation  

E-Print Network [OSTI]

Considered is spherical shell as a model for visible universe and parameters that such model must have to comply with the observable data. The topology of the model requires that motion of all galaxies and light must be confined inside a spherical shell. Consequently the observable universe cannot be defined as a sphere centered on the observer, rather it is an arc length within the volume of the spherical shell. The radius of the shell is 4.46 $\\pm$ 0.06 Gpc, which is for factor $\\pi$ smaller than radius of a corresponding 3-sphere. However the event horizon, defined as the arc length inside the shell, has the size of 14.0 $\\pm$ 0.2 Gpc, which is in agreement with the observable data. The model predicts, without inflation theory, the isotropy and uniformity of the CMB. It predicts the correct value for the Hubble constant $H_0$ = 67.26 $\\pm$ 0.90 km/s/Mpc, the cosmic expansion rate $H(z)$, and the speed of the event horizon in agreement with observations. The theoretical suport for shell model comes from general relativity, curvature of space by mass, and from holographic principle. The model explains the reason for the established discrepancy between the non-covariant version of the holographic principle and the calculated dimensionless entropy $(S/k)$ for the visible universe, which exceeds the entropy of a black hole. The model is in accordance with the distribution of radio sources in space, type Ia data, and data from the Hubble Ultra Deep Field optical and near-infrared survey.

Branislav Vlahovic

2012-07-06T23:59:59.000Z

369

PRECONDITIONED BI-CONJUGATE GRADIENT METHOD FOR RADIATIVE TRANSFER IN SPHERICAL MEDIA  

SciTech Connect (OSTI)

A robust numerical method called the Preconditioned Bi-Conjugate Gradient (Pre-BiCG) method is proposed for the solution of the radiative transfer equation in spherical geometry. A variant of this method called Stabilized Preconditioned Bi-Conjugate Gradient (Pre-BiCG-STAB) is also presented. These are iterative methods based on the construction of a set of bi-orthogonal vectors. The application of the Pre-BiCG method in some benchmark tests shows that the method is quite versatile, and can handle difficult problems that may arise in astrophysical radiative transfer theory.

Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, Bangalore 560 034 (India); Paletou, F.; Leger, L. [Laboratoire d'Astrophysique de Toulouse-Tarbes, Universite de Toulouse, CNRS, 14 Ave. E. Belin, 31400 Toulouse (France)

2009-10-10T23:59:59.000Z

370

Machine imparting complex rotary motion for lapping a spherical inner diameter  

DOE Patents [OSTI]

An apparatus for imparting complex rotary motion is used to lap an inner spherical diameter surface of a workpiece. A lapping tool consists of a dome and rod mounted along the dome's vertical axis. The workpiece containing the lapping tool is held in a gimbal which uses power derived from a secondary takeoff means to impart rotary motion about a horizontal axis. The gimbal is rotated about a vertical axis by a take means while mounted at a radially outward position on a rotating arm.

Carroll, T.A.; Yetter, H.H.

1985-01-30T23:59:59.000Z

371

Semiclassical Estimates of Electromagnetic Casimir Self-Energies of Spherical and Cylindrical Metallic Shells  

E-Print Network [OSTI]

The leading semiclassical estimates of the electromagnetic Casimir stresses on a spherical and a cylindrical metallic shell are within 1% of the field theoretical values. The electromagnetic Casimir energy for both geometries is given by two decoupled massless scalars that satisfy conformally covariant boundary conditions. Surface contributions vanish for smooth metallic boundaries and the finite electromagnetic Casimir energy in leading semiclassical approximation is due to quadratic fluctuations about periodic rays in the interior of the cavity only. Semiclassically the non-vanishing Casimir energy of a metallic cylindrical shell is almost entirely due to Fresnel diffraction.

Martin Schaden

2010-06-16T23:59:59.000Z

372

On the non-relativistic limit of the spherically symmetric Einstein-Vlasov-Maxwell system  

E-Print Network [OSTI]

The Einstein-Vlasov-Maxwell (EVM) system can be viewed as a relativistic generalization of the Vlasov-Poisson (VP) system. As it is proved below, one of nice property obeys by the first system is that the strong energy condition holds and this allows to conclude that the above system is physically viable. We show in this paper that in the context of spherical symmetry, solutions of the perturbed (EVM) system by $\\gamma := 1/c^{2}$, $c$ being the speed of light, exist and converge uniformly in $L^{\\infty}$-norm, as $c$ goes to infinity on compact time intervals to solutions of the non-relativistic (VP) system.

P. Noundjeu

2005-08-19T23:59:59.000Z

373

Instability localized at the inner surface of an imploding spherical shell  

SciTech Connect (OSTI)

It is shown that in an imploding spherical shell the surface instabilities are of two different types. The first, which occurs at the outer surfaces, is the Rayleigh-Taylor instability. The second instability occurs at the inner surface. This latter instability is not as disruptive as R-T modes, but it has three basic properties which differ considerably from those of the R-T instability: (1) it is oscillatory at early times; (2) it grows faster in the long wavelength modes; (3) it depends on the equation of state. It is further shown that this new instability is driven by amplified sound waves in the shell.

Han, S.J.

1983-01-01T23:59:59.000Z

374

Dynamical Instability of Spherical Star in $f(R,T)$ gravity  

E-Print Network [OSTI]

This work is based on stability analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment in $f(R,T)$ gravity, where $R$ is Ricci scalar and $T$ corresponds to the trace of energy momentum tensor. Field equations and dynamical equations are presented in the context of $f(R,T)$ gravity. Perturbation schem is employed on dynamical equations to find the collapse equation. Furthermore, condition on adiabatic index $\\Gamma$ is constructed for Newtonian and post-Newtonian eras to address instability problem. Some constraints on physical quantities are imposed to maintain stable stellar configuration. The results in this work are in accordance with $f(R)$ gravity for specific case.

Ifra Noureen; M. Zubair

2014-11-20T23:59:59.000Z

375

Geometric Design of Spherical Serial Chains with Curvature Constraints in the Environment  

E-Print Network [OSTI]

ed in the rst location and constraint forces in the second location. Thus, the matrix functions [K1(t)] = [K10 ] + [K 1 1 ]t+ 1 2 [K12 ]t 2; [K2(t)] = [K20 ] + [K 2 1 ]t; (3.18) 18 where [Kj0 ], [K j 1 ], j = 1; 2 and [K 1 2... . . . . . . . . . . . . . . . . . . . 18 B. Summary of Planar Research for Contact Speci cations . . 21 IV SPHERICAL VELOCITY AND ACCELERATION CON- STRAINTS DEFINED BY CONTACT AND CURVATURE CONSTRAINTS : : : : : : : : : : : : : : : : : : : : : : : : : : : 22 A. Task Speci cation...

Tolety, Anurag Bharadwaj

2012-10-19T23:59:59.000Z

376

In-medium nucleon-nucleon cross-sections with non-spherical Pauli blocking  

E-Print Network [OSTI]

We present a formalism to solve the Bethe-Goldstone scattering equation without the use of partial wave expansion which is alternative to the one we developed in a previous work. The present approach is more suitable for the calculation of in-medium nucleon-nucleon cross sections, which are the focal point of this paper. The impact of removing the spherical approximation on the angle and energy dependence of, particularly, in-medium proton-proton and proton-neutron differential cross sections is discussed along with its potential implication.

L. White; F. Sammarruca

2014-06-14T23:59:59.000Z

377

Classic tests of General Relativity described by brane-based spherically symmetric solutions  

E-Print Network [OSTI]

We discuss a way to obtain information about higher dimensions from observations by studying a brane-based spherically symmetric solution. The three classic tests of General Relativity are analyzed in details: the perihelion shift of the planet Mercury, the deflection of light by the Sun, and the gravitational redshift of atomic spectral lines. The braneworld version of these tests exhibits an additional parameter $b$ related to the fifth-coordinate. This constant $b$ can be constrained by comparison with observational data for massive and massless particles.

R. R. Cuzinatto; P. J. Pompeia; M. de Montigny; F. C. Khanna; J. M. Hoff da Silva

2014-09-03T23:59:59.000Z

378

Explicit Solution of Worst-Case Secrecy Rate for MISO Wiretap Channels with Spherical Uncertainty  

E-Print Network [OSTI]

A multiple-input single-output (MISO) wiretap channel model is considered, that includes a multi-antenna transmitter, a single-antenna legitimate receiver and a single-antenna eavesdropper. For the scenario in which spherical uncertainty for both the legitimate and the eavesdropper channels is included, the problem of finding the optimal input covariance that maximizes the worst-case secrecy rate subject to a power constraint, is considered, and an explicit expression for the maximum worst-case secrecy rate is provided.

Li, Jiangyuan

2011-01-01T23:59:59.000Z

379

Spherically symmeteric dark energy structure in the context of Chaplygin gas model  

E-Print Network [OSTI]

Spherically symmetric dark energy structures are investigated in the framework of a generalized Chaplygin gas (GCG), which has an equation of state of the form $P = - A/\\rho^{\\alpha}} $. We also study these in a modified GCG equation of state, which includes a matter term, i.e. $P = \\sigma^{2} \\rho - A/\\rho^{\\alpha}$. The results of the latter are then compared with some observational data on low-surface-brightness galaxies which are supposed to be dominated by dark matter.

Abiy G. Tekola

2007-06-06T23:59:59.000Z

380

ABAREX -- A neutron spherical optical-statistical-model code -- A user`s manual  

SciTech Connect (OSTI)

The contemporary version of the neutron spherical optical-statistical-model code ABAREX is summarized with the objective of providing detailed operational guidance for the user. The physical concepts involved are very briefly outlined. The code is described in some detail and a number of explicit examples are given. With this document one should very quickly become fluent with the use of ABAREX. While the code has operated on a number of computing systems, this version is specifically tailored for the VAX/VMS work station and/or the IBM-compatible personal computer.

Smith, A.B. [ed.; Lawson, R.D.

1998-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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.


381

On spherically symmetric metric satisfying the positive kinetic energy coordinate condition  

E-Print Network [OSTI]

Generally speaking, there is a negative kinetic energy term in the Lagrangian of the Einstein-Hilbert action of general relativity; On the other hand, the negative kinetic energy term can be vanished by designating a special coordinate system. For general spherically symmetric metric, the question that seeking special coordinate system that satisfies the positive kinetic energy coordinate condition is referred to solving a linear first-order partial differential equation. And then, we present a metric corresponding to the Reissner-Nordstrom solution that satisfies the positive kinetic energy coordinate condition. Finally, we discuss simply the case of the Tolman metric.

T. Mei

2008-02-28T23:59:59.000Z

382

NSTX-U Digital Coil Protection System Software Detailed Design  

SciTech Connect (OSTI)

The National Spherical Torus Experiment (NSTX) currently uses a collection of analog signal processing solutions for coil protection. Part of the NSTX Upgrade (NSTX-U) entails replacing these analog systems with a software solution running on a conventional computing platform. The new Digital Coil Protection System (DCPS) will replace the old systems entirely, while also providing an extensible framework that allows adding new functionality as desired.

none,

2014-06-01T23:59:59.000Z

383

National Security Photo Gallery | Argonne National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn Cyber Security Nuclear Forensics

384

Sandia National Laboratories: National Solar Thermal Test Facility...  

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

FacilityNational Solar Thermal Test Facility Interest Survey National Solar Thermal Test Facility Interest Survey Company Name * Contact Name * Email * Phone Number * Nature of...

385

Sandia National Laboratories: Officials Turn to Sandia National...  

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

ClimateECResearch & CapabilitiesCapabilitiesOfficials Turn to Sandia National Labs for Help on Huge Sinkhole Officials Turn to Sandia National Labs for Help on Huge Sinkhole...

386

Biomass Feedstock National User Facility  

Broader source: Energy.gov [DOE]

Breakout Session 1BIntegration of Supply Chains I: Breaking Down Barriers Biomass Feedstock National User Facility Kevin L. Kenney, Director, Biomass Feedstock National User Facility, Idaho National Laboratory

387

National Synchrotron Light Source  

ScienceCinema (OSTI)

A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

None

2010-01-08T23:59:59.000Z

388

Perspectives on the National  

E-Print Network [OSTI]

Perspectives on the National Electrical Code ® John Wiles Sponsored by the Photovoltaic Systems systems. Representatives from the photovoltaic (PV) industry, academic institutions, the inspector requirements does not guarantee high levels of performance, higher performance and reliability frequently

Johnson, Eric E.

389

AISES National Conference  

Office of Energy Efficiency and Renewable Energy (EERE)

The AISES National Conference is a one-of-a-kind, three day event convening graduate, undergraduate, and high school junior and senior students, teachers, workforce professionals, corporate and...

390

Alamos National Laboratory  

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

Economic development in Northern New Mexico focus of new podcast from Los Alamos National Laboratory November 25, 2013 Podcast part of Lab's new multi-channel effort to better...

391

National Center Standardsfor  

E-Print Network [OSTI]

American Free Trade Agreement (NAFTA) International Organization for Standardization Information Network and exports Standards organizations, experts, and publications NCSCI helps you with these tools . . . Full texts of standards Indexes to millions of industry, national, regional, and international standards U

392

National Environmental Information Infrastructure  

E-Print Network [OSTI]

National Environmental Information Infrastructure: Reference Architecture Contributing Information Infrastructure: Reference Architecture v1.1 Environmental Information Programme Publication Series: Reference Architecture, Environmental Information Programme Publication Series, document no. 4, Bureau

Greenslade, Diana

393

Argonne National Laboratory  

Broader source: Energy.gov [DOE]

HISTORYThe Argonne National Laboratory (ANL) site is approximately 27 miles southwest of downtown Chicago in DuPage County, Illinois. The 1,500 acre ANL site is completely surrounded by the 2,240...

394

Los Alamos National Laboratory's  

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

takes part in Blue Star Museums program May 16, 2012 Free admission for active duty military, their family members LOS ALAMOS, New Mexico, May 16, 2012-Los Alamos National...

395

Brookhaven National Laboratory  

Broader source: Energy.gov [DOE]

Site OverviewThe Brookhaven National Laboratory (BNL) was established in 1947 by the Atomic Energy Commission (AEC) (predecessor to U.S. Department of Energy [DOE]). Formerly Camp Upton, a U.S....

396

New model of calculating the energy transfer efficiency for the spherical theta-pinch device  

E-Print Network [OSTI]

Ion-beam-plasma-interaction plays an important role in the field of Warm Dense Matter (WDM) and Inertial Confinement Fusion (ICF). A spherical theta pinch is proposed to act as a plasma target in various applications including a plasma stripper cell. One key parameter for such applications is the free electron density. A linear dependency of this density to the amount of energy transferred into the plasma from an energy storage was found by C. Teske. Since the amount of stored energy is known, the energy transfer efficiency is a reliable parameter for the design of a spherical theta pinch device. The traditional two models of energy transfer efficiency are based on assumptions which comprise the risk of systematical errors. To obtain precise results, this paper proposes a new model without the necessity of any assumption to calculate the energy transfer efficiency for an inductively coupled plasma device. Further, a comparison of these three different models is given at a fixed operation voltage for the full ...

Xu, G; Loisch, G; Xiao, G; Jacoby, J; Weyrich, K; Li, Y; Zhao, Y

2015-01-01T23:59:59.000Z

397

Two non-comoving stiff fluids in radial motion and spherical symmetry  

E-Print Network [OSTI]

The problem of two stiff fluids (energy density = pressure) moving radially in spherical symmetry is treated. The metric ansatz is chosen spherically symmetric, conformally static with a multiplicative separation of variables. The first fluid is described mathematically via a massless scalar field. The coordinate system is chosen comoving with the second fluid which the separation of variables requires to be stiff too. The fluids are interacting only gravitationally and their energy momentum tensors are separately conserved. The Einstein equations are reduced to a single nonlinear ODE of second order which is shown to lead to an Abel ODE. A few particular exact solutions were found using a polynomial ansatz. The two non-comoving gravitational sources in the solutions can be interpreted either as scalar fields or stiff fluids. A complete analysis is performed on the range of parameters for which the stiff fluid interpretation is physically acceptable. General formulas are derived for the conformal vectors of the solutions. By making the second fluid vanish, a few single scalar field solutions are generated some of which appear to be new. All solutions considered in this paper have a time-like singularity at the origin (except the trivial FRW one) and are not asymptotically flat (except the static one with k=0).

Valentin Kostov

2008-11-04T23:59:59.000Z

398

Generalized spherically symmetric gravitational model: Hamiltonian dynamics in extended phase space and BRST charge  

E-Print Network [OSTI]

We construct Hamiltonian dynamics of the generalized spherically symmetric gravitational model in extended phase space. We start from the Faddeev - Popov effective action with gauge-fixing and ghost terms, making use of gauge conditions in differential form. It enables us to introduce missing velocities into the Lagrangian and then construct a Hamiltonian function according a usual rule which is applied for systems without constraints. The main feature of Hamiltonian dynamics in extended phase space is that it can be proved to be completely equivalent to Lagrangian dynamics derived from the effective action. We find a BRST invariant form of the effective action by adding terms not affecting Lagrangian equations. After all, we construct the BRST charge according to the Noether theorem. Our algorithm differs from that by Batalin, Fradkin and Vilkovisky, but the resulting BRST charge generates correct transformations for all gravitational degrees of freedom including gauge ones. Generalized spherically symmetric model imitates the full gravitational theory much better then models with finite number of degrees of freedom, so that one can expect appropriate results in the case of the full theory.

T. P. Shestakova

2014-06-12T23:59:59.000Z

399

Electric double layer for a size-asymmetric electrolyte around a spherical colloid  

SciTech Connect (OSTI)

We have studied the structure of a size-asymmetric electrolyte on charged colloids by a density functional perturbation theory. The hard-sphere contribution has been approximated as the direct pair correlation function with the coupling parameter, whereas the electronic contribution has been approximated as the mean-spherical approximation in the bulk phase. The calculated results for the ionic density distributions and mean electrostatic potentials are in very good agreement with the computer simulations over a wide range of colloid sizes and electrolyte concentrations. The present theory provides better structural results than the hypernetted-chain equation based on the mean spherical approximation. We have confirmed that the overcharging appears when the counterions are larger than the coions. The overcharging disappears everywhere when the electrostatic repulsion becomes strong enough, while the charge reversal is observed when the coions are larger than the counterions, and the reversal effect appears for a size-asymmetric electrolyte at high surface charge densities. The charge reversal occurs even for the point of zero charge, mainly due to the depletion force between two ions. The present theory is able to provide interesting insights about the charge reversal and overcharging phenomena occurring at the interface.

Kim, Eun-Young; Kim, Soon-Chul, E-mail: sckim@andong.ac.kr [Department of Physics, Andong National University, Andong 760-749 (Korea, Republic of)] [Department of Physics, Andong National University, Andong 760-749 (Korea, Republic of)

2014-04-21T23:59:59.000Z

400

Characterization of a Spherical Proportional Counter in argon-based mixtures  

E-Print Network [OSTI]

The Spherical Proportional Counter is a novel type of radiation detector, with a low energy threshold (typically below 100 eV) and good energy resolution. This detector is being developed by the network NEWS, which includes several applications. We can name between many others Dark Matter searches, low level radon and neutron counting or low energy neutrino detection from supernovas or nuclear reactors via neutrino-nucleus elastic scattering. In this context, this works will present the characterization of a spherical detector of 1 meter diameter using two argon-based mixtures (with methane and isobutane) and for gas pressures between 50 and 1250 mbar. In each case, the energy resolution shows its best value in a wide range of gains, limited by the ballistic effect at low gains and by ion-backflow at high gains. Moreover, the best energy resolution shows a degradation with pressure. These effects will be discussed in terms of gas avalanche properties. Finally, the effect of an electrical field corrector in the homogenity of the gain and the energy threshold measured in our setup will be also discussed.

F. J. Iguaz; A. Rodriguez; J. F. Castel; I. G. Irastorza

2015-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "national spherical torus" 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

Characterization of a Spherical Proportional Counter in argon-based mixtures  

E-Print Network [OSTI]

The Spherical Proportional Counter is a novel type of radiation detector, with a low energy threshold (typically below 100 eV) and good energy resolution. This detector is being developed by the network NEWS, which includes several applications. We can name between many others Dark Matter searches, low level radon and neutron counting or low energy neutrino detection from supernovas or nuclear reactors via neutrino-nucleus elastic scattering. In this context, this works will present the characterization of a spherical detector of 1 meter diameter using two argon-based mixtures (with methane and isobutane) and for gas pressures between 50 and 1250 mbar. In each case, the energy resolution shows its best value in a wide range of gains, limited by the ballistic effect at low gains and by ion-backflow at high gains. Moreover, the best energy resolution shows a degradation with pressure. These effects will be discussed in terms of gas avalanche properties. Finally, the effect of an electrical field corrector in th...

Iguaz, F J; Castel, J F; Irastorza, I G

2015-01-01T23:59:59.000Z

402

Oversight Reports - Argonne National Laboratory | Department...  

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

Argonne National Laboratory Oversight Reports - Argonne National Laboratory August 24, 2012 Independent Activity Report, Argonne National Laboratory - July 2012 Operational...

403

National Electric Transmission Congestion Study Webinars | Department...  

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

National Electric Transmission Congestion Study National Electric Transmission Congestion Study Webinars National Electric Transmission Congestion Study Webinars The Department...

404

Linear stability of spherically symmetric and wormhole solutions supported by the sine-Gordon ghost scalar field  

SciTech Connect (OSTI)

In this paper we investigate wormhole and spherically symmetric solutions in four-dimensional gravity plus a matter source consisting of a ghost scalar field with a sine-Gordon potential. For the wormhole solutions we also include the possibility of electric and/or magnetic charges. For both types of solutions we perform a linear stability analysis and show that the wormhole solutions are stable and that when one turns on the electric and/or magnetic field the solution remains stable. The linear stability analysis of the spherically symmetric solutions indicates that they can be stable or unstable depending on one of the parameters of the system. This result for the spherically symmetric solution is nontrivial since a previous investigation of four-dimensional gravity plus a ghost scalar field with a {lambda}{phi}{sup 4} interaction found only unstable spherically symmetric solutions. Both the wormhole and spherically symmetric solutions presented here asymptotically go to anti-de Sitter space-time.

Dzhunushaliev, Vladimir [Institute for Basic Research, Eurasian National University, Astana, 010008 (Kazakhstan); Institute of Physicotechnical Problems and Material Science of the NAS of the Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Institut fuer Physik, Universitaet Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany); Folomeev, Vladimir [Institute of Physicotechnical Problems and Material Science of the NAS of the Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Institut fuer Physik, Universitaet Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany); Singleton, Douglas [Physics Department, CSU Fresno, Fresno, California 93740-8031 (United States); Myrzakulov, Ratbay [Eurasian International Center for Theoretical Physics and Department of General and Theoretical Physics, Eurasian National University, Astana, 010008 (Kazakhstan)

2010-08-15T23:59:59.000Z

405

UNIVERSITY OF CANADA FIRST NATIONS  

E-Print Network [OSTI]

UNIVERSITY DRIVE NORTH UNIVERSITYDRIVEEAST LIFT STATION BASEBALL DIAMOND FIRST NATIONS WAY FIRST NATIONS WAY G UNIVERSITYDRIVEWEST ENGINEERING GARAGE ARTIFICIAL TURF FIELD EASTLOOPROAD PLAYING FIELD 1

Argerami, Martin

406

with Oak Ridge National Laboratory  

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

2 Mechanisms for Partnering with Oak Ridge National Laboratory Partnerships-It's our name, but it also represents our driving philosophy and commitment. Oak Ridge National...

407

Climate Change and National Security  

E-Print Network [OSTI]

CLIMATE CHANGE Multiplying Threats to National Securityfor the impacts of climate change on national security. Pagea warming world. Page 11 Climate change acts as a threat

Alyson, Fleming; Summer, Kelly; Summer, Martin; Lauren, Franck; Jonathan, Mark

2015-01-01T23:59:59.000Z

408

NONLINEAR RESPONSE OF A SPHERICAL BUBBLE TO A MULTI-FREQUENCY EXCITATION NAYFEH A.H. and MOOK D.T.  

E-Print Network [OSTI]

nonlinear radial oscillations of a spherical gas bubble are / 6 / where the dot denotes d i f f e r e n t iNONLINEAR RESPONSE OF A SPHERICAL BUBBLE TO A MULTI-FREQUENCY EXCITATION NAYFEH A.H. and MOOK D of a spherical gas bubble immersed in a s l i g h t l y compressible f l u i d . The mass of the gas bubble

Paris-Sud XI, Université de

409

National Ignition Facility | National Nuclear Security Administration  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn F.Demonstrate PromisingElectedEnergy33997000 |

410

Lawrence Livermore National Laboratory | National Nuclear Security  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 Lawrence Livermore National Laboratory

411

National Nuclear Security Administration | National Nuclear Security  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review of the Yucca0Administration Names15-16

412

Previous Sandia National Laboratories | National Nuclear Security  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review of theOFFICE OF CIVIL RIGHTS/%2A en10

413

Researcher, Sandia National Laboratories | National Nuclear Security  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared atEffect of DryCorrectionComplexAdministration | National

414

Sandia National Laboratories | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' |RequestsAdministration devote

415

Sandia National Laboratories | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' |RequestsAdministration devoteAllison Davis Sandia

416

Sandia National Laboratories | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' |RequestsAdministration devoteAllison Davis

417

Sandia National Laboratories | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' |RequestsAdministration devoteAllison DavisSandia

418

Sandia National Laboratories: Sandia National Laboratories: Missions:  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive SolarEducationStationCSPRecoveryTopPolanyiPacific Northwest NationalDefense

419

Sandia National Laboratories: FEMA National Exercise Division  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLS Exhibit at Explora Museum On AprilExplora MuseumFEMA National

420

Sandia National Laboratories: Los Alamos National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLS ExhibitIowaLos Alamos National Laboratory Consortium for

Note: This page contains sample records for the topic "national spherical torus" 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.


421

Sandia National Laboratories: National Electrical Code  

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

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422

Sandia National Laboratories: National Renewable Energy Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLSMolten-Salt Storage System ArevaNRGAnalysis CenterNational

423

A multi-resolution method for climate system modeling: application of Spherical Centroidal A multi-resolution method for climate system modeling: Application of Spherical Centroidal Voroni Tessellations  

SciTech Connect (OSTI)

During the next decade and beyond, climate system models will be challenged to resolve scales and processes that are far beyond their current scope. Each climate system component has its prototypical example of an unresolved process that may strongly influence the global climate system, ranging from eddy activity within ocean models, to ice streams within ice sheet models, to surface hydrological processes within land system models, to cloud processes within atmosphere models. These new demands will almost certainly result in the develop of multi-resolution schemes that are able, at least regional to faithfully simulate these fine-scale processes. Spherical Centroidal Voronoi Tessellations (SCVTs) offer one potential path toward the development of robust, multi-resolution climate system component models, SCVTs allow for the generation of high quality Voronoi diagrams and Delaunay triangulations through the use of an intuitive, user-defined density function, each of the examples provided, this method results in high-quality meshes where the quality measures are guaranteed to improve as the number of nodes is increased. Real-world examples are developed for the Greenland ice sheet and the North Atlantic ocean. Idealized examples are developed for ocean-ice shelf interaction and for regional atmospheric modeling. In addition to defining, developing and exhibiting SCVTs, we pair this mesh generation technique with a previously developed finite-volume method. Our numerical example is based on the nonlinear shallow-water equations spanning the entire surface of the sphere. This example is used to elucidate both the potential benefits of this multi-resolution method and the challenges ahead.

Ringler, Todd D [Los Alamos National Laboratory; Gunzburger, Max [FLORIDA STATE UNIV; Ju, Lili [UNIV OF SOUTH CAROLINA

2008-01-01T23:59:59.000Z

424

Lawrence Berkeley National Laboratory Overview  

Office of Energy Efficiency and Renewable Energy (EERE)

Presentation about the history, structure, and projects of the Lawrence Berkeley National Laboratory.

425

Jobs at the National Labs  

Broader source: Energy.gov [DOE]

Search for jobs, internships and educational programs at the Department of Energy's National Laboratories.

426

A Compressible High-Order Unstructured Spectral Difference Code for Stratified Convection in Rotating Spherical Shells  

E-Print Network [OSTI]

We present a novel and powerful Compressible High-ORder Unstructured Spectral-difference (CHORUS) code for simulating thermal convection and related fluid dynamics in the interiors of stars and planets. The computational geometries are treated as rotating spherical shells filled with stratified gas. The hydrodynamic equations are discretized by a robust and efficient high-order Spectral Difference Method (SDM) on unstructured meshes. The computational stencil of the spectral difference method is compact and advantageous for parallel processing. CHORUS demonstrates excellent parallel performance for all test cases reported in this paper, scaling up to 12,000 cores on the Yellowstone High-Performance Computing cluster at NCAR. The code is verified by defining two benchmark cases for global convection in Jupiter and the Sun. CHORUS results are compared with results from the ASH code and good agreement is found. The CHORUS code creates new opportunities for simulating such varied phenomena as multi-scale solar co...

Wang, Junfeng; Miesch, Mark S

2015-01-01T23:59:59.000Z

427

Spherical Solutions in Einstein-Aether Theory: Static Aether and Stars  

E-Print Network [OSTI]

The time independent spherically symmetric solutions of General Relativity (GR) coupled to a dynamical unit timelike vector are studied. We find there is a three-parameter family of solutions with this symmetry. Imposing asymptotic flatness restricts to two parameters, and requiring that the aether be aligned with the timelike Killing field further restricts to one parameter, the total mass. These "static aether" solutions are given analytically up to solution of a transcendental equation. The positive mass solutions have spatial geometry with a minimal area 2-sphere, inside of which the area diverges at a curvature singularity occurring at an extremal Killing horizon that lies at a finite affine parameter along a radial null geodesic. Regular perfect fluid star solutions are shown to exist with static aether exteriors, and the range of stability for constant density stars is identified.

Christopher Eling; Ted Jacobson

2009-12-06T23:59:59.000Z

428

Some comments on the nature of initial data in spherical collapse  

E-Print Network [OSTI]

Various authors have shown the occurence of naked singularities and black holes in the spherical gravitational collapse of inhomogeneous dust. In a recent preprint, Antia has criticised a statement in a paper by Jhingan, Joshi and Singh on dust collapse. We show that his criticism is invalid. Antia shows that in Eulerian coordinates a series expansion for the density of a collapsing Newtonian fluid can have only even powers. However, he has overlooked the fact that Jhingan et al. have actually used Lagrangian (comoving) coordinates, and not Eulerian coordinates. As we show, in Lagrangian coordinates there is no restriction that the density have only even powers and hence his criticism is invalid. We also point out that an earlier claim by Antia on the instability of strong naked singularities in dust collapse is not supported by any concrete analysis, and is hence incorrect.

T. P. Singh

1997-02-12T23:59:59.000Z

429

How does torsional rigidity affect the wrapping transition of a semiflexible chain around a spherical core?  

E-Print Network [OSTI]

We investigated the effect of torsional rigidity of a semiflexible chain on the wrapping transition around a spherical core, as a model of nucleosome, the fundamental unit of chromatin. Through molecular dynamics simulation, we show that the torsional effect has a crucial effect on the chain wrapping around the core under the topological constraints. In particular, the torsional stress (i) induces the wrapping/unwrapping transition, and (ii) leads to a unique complex structure with an antagonistic wrapping direction which never appears without the topological constraints. We further examine the effect of the stretching stress for the nucleosome model, in relation to the unique characteristic effect of the torsional stress on the manner of wrapping.

Yuji Higuchi; Takahiro Sakaue; Kenichi Yoshikawa

2010-04-22T23:59:59.000Z

430

Calculation of the fast ion tail distribution for a spherically symmetric hot spot  

SciTech Connect (OSTI)

The fast ion tail for a spherically symmetric hot spot is computed via the solution of a simplified Fokker-Planck collision operator. Emphasis is placed on describing the energy scaling of the fast ion distribution function in the hot spot as well as the surrounding cold plasma throughout a broad range of collisionalities and temperatures. It is found that while the fast ion tail inside the hot spot is significantly depleted, leading to a reduction of the fusion yield in this region, a surplus of fast ions is observed in the neighboring cold plasma region. The presence of this surplus of fast ions in the neighboring cold region is shown to result in a partial recovery of the fusion yield lost in the hot spot.

McDevitt, C. J.; Tang, X.-Z.; Guo, Z. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Berk, H. L. [Department of Physics, University of Texas, Austin, Texas 78712 (United States)

2014-10-15T23:59:59.000Z

431

Ionic density distributions near the charged colloids: Spherical electric double layers  

SciTech Connect (OSTI)

We have studied the structure of the spherical electric double layers on charged colloids by a density functional perturbation theory, which is based both on the modified fundamental-measure theory for the hard spheres and on the one-particle direct correlation functional (DCF) for the electronic residual contribution. The contribution of one-particle DCF has been approximated as the functional integration of the second-order correlation function of the ionic fluids in a bulk phase. The calculated result is in very good agreement with the computer simulations for the ionic density distributions and the zeta potentials over a wide range of macroion sizes and electrolyte concentrations, and compares with the results of Yu et al. [J. Chem. Phys. 120, 7223 (2004)] and modified Poisson-Boltzmann approximation [L. B. Bhuiyan and C. W. Outhwaite, Condens. Matter Phys. 8, 287 (2005)]. The present theory is able to provide interesting insights about the charge inversion phenomena occurring at the interface.

Kim, Eun-Young; Kim, Soon-Chul, E-mail: sckim@andong.ac.kr [Department of Physics, Andong National University, Andong 760-749 (Korea, Republic of)] [Department of Physics, Andong National University, Andong 760-749 (Korea, Republic of)

2013-11-21T23:59:59.000Z

432

On the statistical mechanics of shape fluctuations of nearly spherical lipid vesicle  

E-Print Network [OSTI]

The mechanical properties of biological membranes play an important role in the structure and the functioning of living organisms. One of the most widely used methods for determination of the bending elasticity modulus of the model lipid membranes (simplified models of the biomembranes with similar mechanical properties) is analysis of the shape fluctuations of the nearly spherical lipid vesicles. A theoretical basis of such an analysis is developed by Milner and Safran. In the present studies we analyze their results using an approach based on the Bogoljubov inequalities and the approximating Hamiltonian method. This approach is in accordance with the principles of statistical mechanics and is free of contradictions. Our considerations validate the results of Milner and Safran if the stretching elasticity K_s of the membrane tends to zero.

I. Bivas; N. S. Tonchev

2014-09-12T23:59:59.000Z

433

PT-Rotations, PT-Spherical Harmonics and the PT-Hydrogen Atom  

E-Print Network [OSTI]

We have constructed a set of non-Hermitian operators that satisfy the commutation relations of the SO(3)-Lie algebra. It is shown that this operators generate rotations in the configuration space and not in the momentum space but in a modified non-Hermitian momentum space. This generators are related with a new type of spherical harmonics that result to be PT-orthonormal. Additionally, we have shown that this operators represent conserved quantities for a non-Hermitian Hamiltonian with an additional complex term. As a particular case, the solutions of the corresponding PT-Hydrogen atom that includes a complex term are obtained, and it is found that a non-Hermitian Runge-Lenz vector is a conserved quantity. In this way, we obtain a set of non-Hermitian operators that satisfy the SO(4)-Lie algebra.

Juan M. Romero; R. Bernal-Jaquez; O. Gonzalez-Gaxiola

2010-01-11T23:59:59.000Z

434

Perihelion precession and deflection of light in the general spherically symmetric spacetime  

E-Print Network [OSTI]

In this paper, the perihelion precession and deflection of light have been investigated in the 4-dimensional general spherically symmetric spacetime, and the main equation is obtained. As the application of this main equation, the Reissner-Nordstorm-AdS solution and Clifton-Barrow solution in $f(R)$ gravity have been taken for the examples. We find that both the electric charge and $f(R)$ gravity can affect the perihelion precession and deflection of light, while the cosmological constant can only effect the perihelion precession. Moreover, we clarify a subtlety in the deflection of light in the solar system that the possible sun's electric charge is usually used to interpret the gap between the experiment data and theoretical result. However, after also considering the effect from the sun's same electric charge on the perihelion precession of Mercury, we can find that it is not the truth.

Ya-Peng Hu; Hongsheng Zhang; Jun-Peng Hou; Liang-Zun Tang

2014-11-27T23:59:59.000Z

435

Fermion Absorption Cross Section and Topology of Spherically Symmetric Black Holes  

E-Print Network [OSTI]

In 1997, Liberati and Pollifrone in Phys. Rev. D56 (1997) 6458 (hep-th/9708014) achieved a new formulation of the Bekenstein-Hawking formula, where the entropy and the Euler characteristic are related by $S=\\chi A/8$. In this work we present a relation between the low-energy absorption cross section for minimally coupled fermions and the Euler characteristic of (3+1)-dimensional spherically symmetric black holes, i.e. $\\sigma =\\chi g_h^{-1}A$. Based on the relation, using the Gauss--Bonnet--Chern theorem and the $\\phi$-mapping method, an absorption cross section density is introduced to describe the topology of the absorption cross section. It is shown that the absorption cross section and its density are determined by the singularities of the timelike Killing vector field of the spacetime and these singularities carry the topological numbers, Hopf indices and Brouwer degrees, naturally.

Yu-Xiao Liu; Li Zhao; Zhen-Bin Cao; Yi-Shi Duan

2007-02-18T23:59:59.000Z

436

Microscopic description of spherical to {gamma}-soft shape transitions in Ba and Xe nuclei  

SciTech Connect (OSTI)

The rapid transition between spherical and {gamma}-soft shapes in Ba and Xe nuclei in the mass region A>=130 is analyzed using excitation spectra and collective wave functions obtained by diagonalization of a five-dimensional Hamiltonian for quadrupole vibrational and rotational degrees of freedom, with parameters determined by constrained self-consistent relativistic mean-field calculations for triaxial shapes. The results reproduce the characteristic evolution of excitation spectra and E2 transition probabilities, and in general, a good agreement with available data is obtained. The calculated spectra display fingerprints of a second-order shape phase transition that can approximately be described by analytic solutions corresponding to the E(5) dynamical symmetry.

Li, Z. P. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Niksic, T.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Meng, J. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China)

2010-03-15T23:59:59.000Z

437

Symmetries of the Energy-Momentum Tensor of Spherically Symmetric Lorentzian Manifolds  

E-Print Network [OSTI]

Matter collineations of spherically Symmetric Lorentzian Manifolds are considered. These are investigated when the energy-momentum tensor is non-degenerate and also when it is degenerate. We have classified spacetimes admitting higher symmetries and spacetimes admitting SO(3) as the maximal isometry group. For the non-degenerate case, we obtain either {\\it four}, {\\it six}, {\\it seven} or {\\it ten} independent matter collineations in which {\\it four} are isometries and the rest are proper. The results of the previous paper [1] are recovered as a special case. It is worth noting that we have also obtained two cases where the energy-momentum tensor is degenerate but the group of matter collineations is finite-dimensional, i.e. {\\it four} or {\\it ten}.

M. Sharif

2003-07-29T23:59:59.000Z

438

Radial Structure of Shell Modulations Near Peak Compression of Spherical Implosions  

SciTech Connect (OSTI)

The structure of shell modulations is measured at peak compression of directly driven spherical implosions using absorption of titanium-doped layers placed at various distances of 1, 5, 7, and 9 mm from the inner surface of 20-mm-thick plastic CH shells filled with 18 atm of D3He gas. The modulations are measured using the ratios of monochromatic core images taken inside and outside of the titanium 1s-2p absorption spectral region. Peak-compression, time-integrated areal-density modulations are higher at the inner shell surface, which is unstable during the deceleration phase of an implosion with a modulation level of 59{+-}14%, The perturbations are lower in the central part of the shell, having a modulation level of 18{+-}5%. The outer surface of the shell, which is unstable during the acceleration phase of an implosion, has a modulation level of 52{+-}20%.

Smalyuk, V.A.; Dumanis, S.B.; Marshall, F.J.; Delettrez, J.A.; Meyerhofer, D.D.; Regan, S.P.; Sangster, T.C.; Yaakobi, B.; Koch, J.A.

2003-03-11T23:59:59.000Z

439

A Star on Earth  

ScienceCinema (OSTI)

At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

2014-06-06T23:59:59.000Z

440

A Star on Earth  

SciTech Connect (OSTI)

At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

2014-03-05T23:59:59.000Z

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441

National Security Science  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn Cyber Security Nuclear ForensicsScience National

442

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review of the Yucca0Administration Names15-16 | National

443

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review of the Yucca0Administration Names15-16 | National

444

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with GenQuest,

445

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with

446

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with24, 2001

447

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with24, 2001FOR

448

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with24,

449

National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude' | NationalADR services are contracted with24,20

450

National Security, Weapons Science  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell Batteries &NST DivisionNationalEnergySafetyNational

451

National Nuclear Security Administration  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy Login The National

452

National Nuclear Security Administration  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy Login The NationalWashington. DC

453

National Security Science  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andDataNational Library of Energy LoginofNational SecuritySecurity

454

Determining the nature of orbits in disk galaxies with non spherical nuclei  

E-Print Network [OSTI]

We investigate the regular or chaotic nature of orbits of stars moving in the meridional plane $(R,z)$ of an axially symmetric galactic model with a flat disk and a central, non spherical and massive nucleus. In particular, we study the influence of the flattening parameter of the central nucleus on the nature of orbits, by computing in each case the percentage of chaotic orbits, as well as the percentages of orbits of the main regular families. In an attempt to maximize the accuracy of our results upon distinguishing between regular and chaotic motion, we use both the Fast Lyapunov Indicator (FLI) and the Smaller ALingment Index (SALI) methods to extensive samples of orbits obtained by integrating numerically the equations of motion as well as the variational equations. Moreover, a technique which is based mainly on the field of spectral dynamics that utilizes the Fourier transform of the time series of each coordinate is used for identifying the various families of regular orbits and also to recognize the secondary resonances that bifurcate from them. Varying the value of the flattening parameter, we study three different cases: (i) the case where we have a prolate nucleus (ii) the case where the central nucleus is spherical and (iii) the case where an oblate massive nucleus is present. Furthermore, we present some additional findings regarding the reliability of short time (fast) chaos indicators, as well as a new method to define the threshold between chaos and regularity for both FLI and SALI, by using them simultaneously. Comparison with early related work is also made.

Euaggelos E. Zotos; Nicolaos D. Caranicolas

2014-04-15T23:59:59.000Z

455

Optimization approach for the computation of magnetohydrostatic coronal equilibria in spherical geometry  

E-Print Network [OSTI]

Context: This paper presents a method which can be used to calculate models of the global solar corona from observational data. Aims: We present an optimization method for computing nonlinear magnetohydrostatic equilibria in spherical geometry with the aim to obtain self-consistent solutions for the coronal magnetic field, the coronal plasma density and plasma pressure using observational data as input. Methods: Our code for the self-consistent computation of the coronal magnetic fields and the coronal plasma solves the non-force-free magnetohydrostatic equilibria using an optimization method. Previous versions of the code have been used to compute non-linear force-free coronal magnetic fields from photospheric measurements in Cartesian and spherical geometry, and magnetostatic-equilibria in Cartesian geometry. We test our code with the help of a known analytic 3D equilibrium solution of the magnetohydrostatic equations. The detailed comparison between the numerical calculations and the exact equilibrium solutions is made by using magnetic field line plots, plots of density and pressure and some of the usual quantitative numerical comparison measures. Results: We find that the method reconstructs the equilibrium accurately, with residual forces of the order of the discretisation error of the analytic solution. The correlation with the reference solution is better than 99.9% and the magnetic energy is computed accurately with an error of <0.1%. Conclusions: We applied the method so far to an analytic test case. We are planning to use this method with real observational data as input as soon as possible.

T. Wiegelmann; T. Neukirch; P. Ruan; B. Inhester

2008-01-18T23:59:59.000Z

456

New Solicitations | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

National Laser User Facilities Program New Solicitations New Solicitations National Laser Users' Facility Grant Program...

457

E-Print Network 3.0 - advance project formal Sample Search Results  

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

Spherical Torus Experiment Collection: Plasma Physics and Fusion 74 DA Associate Program -AeS Proposal Ongoing development Summary: results make the formal development a standard...

458

Dale M. Meade Presented at  

E-Print Network [OSTI]

Fourth Phase Scientific Feasibility Burning Demo Engineering Base Electric Power Feasibility Economic Feasibility Burning Demo Engineering Base Electric Power Feasibility Economic Feasibility Spherical Torus RFP

459

National Security System Manual  

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

The manual provides baseline requirements and controls for the graded protection of the confidentiality, integrity, and availability of classified information and information systems used or operated by the Department of Energy (DOE), contractors, and any other organization on behalf of DOE, including the National Nuclear Security Administration. Cancels DOE M 471.2-2. Canceled by DOE O 205.1B.

2007-03-08T23:59:59.000Z

460

National Laboratory Dorene Price  

E-Print Network [OSTI]

: price@bnl.gov ELECTROCHEMICAL ENHANCEMENT OF BIO-ETHANOL AND METABOLITE PRODUCTION Brookhaven National as a manufacturing step in their process to produce bio-ethanol or other commercially used metabolites can implement ApplicationFiled 61/042,867 TECHNOLOGY This method accelerates the production of ethanol and other metabolites

Note: This page contains sample records for the topic "national spherical torus" 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

National Laboratory Contacts  

Broader source: Energy.gov [DOE]

Several of the U.S. Department of Energy (DOE) national laboratories host multidisciplinary transportation research centers. A wide-range of cutting-edge transportation research occurs at these facilities, funded by both DOE and cooperative research and development agreements (CRADAs) with industry

462

Scholarship Fund (National Forestry  

E-Print Network [OSTI]

Forestry Scholarship Fund (National Forestry Master's Program (NFMP) The Forestry Scholarship Fund! 2014 Scholarship Offers A degree in forestry is a way of life. Trees, people, habitats, management that you will experience when you chose forestry as a career. #12;TRUSTEE FOR FORESTRY SCHOLARSHIP FUND ABN

Botea, Adi

463

United Nations Development Programme  

E-Print Network [OSTI]

Energy Concessions: Pilot Programs 7.5. Modernising Corn Stover Use in Rural Jilin Province, China 7United Nations Development Programme Bureau for Development Policy Energy and Atmosphere Programme. #12;5 Acknowledgements 6 Notes on Authors 7 Foreword 9 Executive Summary 27 Introduction: Energy

464

Sandia National Laboratories  

E-Print Network [OSTI]

Sandia National Laboratories 7011 East Ave. Livermore, CA 94550 Las Positas College 3000 Campus competitions scheduled for the California Bay Area. The Science Bowl is a Jeopardy-like highly competitive Area competitions: Date (all on Saturdays): Location: Host: Regional HIGH SCHOOL Science Bowls January

465

Comprehensive national energy strategy  

SciTech Connect (OSTI)

This Comprehensive National Energy Strategy sets forth a set of five common sense goals for national energy policy: (1) improve the efficiency of the energy system, (2) ensure against energy disruptions, (3) promote energy production and use in ways that respect health and environmental values, (4) expand future energy choices, and (5) cooperate internationally on global issues. These goals are further elaborated by a series of objectives and strategies to illustrate how the goals will be achieved. Taken together, the goals, objectives, and strategies form a blueprint for the specific programs, projects, initiatives, investments, and other actions that will be developed and undertaken by the Federal Government, with significant emphasis on the importance of the scientific and technological advancements that will allow implementation of this Comprehensive National Energy Strategy. Moreover, the statutory requirement of regular submissions of national energy policy plans ensures that this framework can be modified to reflect evolving conditions, such as better knowledge of our surroundings, changes in energy markets, and advances in technology. This Strategy, then, should be thought of as a living document. Finally, this plan benefited from the comments and suggestions of numerous individuals and organizations, both inside and outside of government. The Summary of Public Comments, located at the end of this document, describes the public participation process and summarizes the comments that were received. 8 figs.

NONE

1998-04-01T23:59:59.000Z

466

National Renewable Energy Laboratory  

E-Print Network [OSTI]

Hydrogen-Production Technology Hydrogen offers great promise as a clean fuel in our nation's energy research and collaboration to improve the durability of photovoltaic cells for PEC hydrogen production-indium-phosphide/ gallium-arsenide) with an impressive 12.4% solar-to-hydrogen efficiency. Unfortunately, the tandem cell

467

Local Casimir Energies for a Thin Spherical Shell Ines CaveroPelaez, # Kimball A. Milton, + and Je#rey Wagner #  

E-Print Network [OSTI]

Local Casimir Energies for a Thin Spherical Shell In??es Cavero­Pel??aez, # Kimball A. Milton of the energy density as the surface of the shell is approached is studied in both the strong and weak coupling light on the nature of surface divergences and on the energy contained within the shell, are obtained

Milton, Kim

468

Sound radiation from a loudspeaker, from a spherical pole cap, and from a piston in an infinite baffle1  

E-Print Network [OSTI]

Sound radiation from a loudspeaker, from a spherical pole cap, and from a piston in an infinite are often modelled as a rigid piston in an infinite baffle. As a model for real loudspeakers, this approach of the baffled-piston radiation the spatial impulse response is presented. 1. Nijboer-Zernike approach

469

A 3D INTENSITY MODEL BASED ON SPHERICAL HARMONICS FOR AUTOMATIC 3D SEGMENTATION OF HETEROCHROMATIN FOCI  

E-Print Network [OSTI]

A 3D INTENSITY MODEL BASED ON SPHERICAL HARMONICS FOR AUTOMATIC 3D SEGMENTATION OF HETEROCHROMATIN DKFZ Heidelberg and BIOQUANT, Research Group Genome Organization & Function ABSTRACT We introduce a 3D model-based approach for automatic segmentation of 3D fluorescent heterochromatin foci from microscopy

Rippe, Karsten

470

PREPRINT; TO APPEAR IN MED PHYS VOL 35 ISSUE 2 Accurate registration of random radiographic projections based on three spherical  

E-Print Network [OSTI]

) reconstruction such as computed tomography (CT) are based on an extensive set of projections from all around projections based on three spherical references for the purpose of few-view 3D reconstruction. Ralf Schulze, Oliver Weinheimer, Daniel Gross, and Elmar Schoemer Institute of Computer Science Johannes Gutenberg

Schömer, Elmar

471

State Transition, Balancing, Station Keeping, and Yaw Control for a Dynamically Stable Single Spherical Wheel Mobile Robot  

E-Print Network [OSTI]

with a four-motor inverse mouse- ball drive, yaw drive, leg drive, control system, and results including present the results and conclusions. II. SYSTEM DESCRIPTION A. Four-Motor Inverse Mouse-Ball Drive Spherical Wheel Mobile Robot Umashankar Nagarajan, Anish Mampetta, George A. Kantor and Ralph L. Hollis

472

A STUDY ON SPHERICAL EXPANDING FLAME SPEEDS OF METHANE, ETHANE, AND METHANE/ETHANE MIXTURES AT ELEVATED PRESSURES  

E-Print Network [OSTI]

High-pressure experiments and chemical kinetics modeling were performed for laminar spherically expanding flames for methane/air, ethane/air, methane/ethane/air and propane/air mixtures at pressures between 1 and 10 atm and equivalence ratios...

De Vries, Jaap

2010-07-14T23:59:59.000Z

473

3. A. A. Sadovoi and N. M. Chulkov, "Distribution of kinetic energy dissipation into thermal energy over a spherical shell thickness because of viscosity," in: Calculation Algorithms  

E-Print Network [OSTI]

3. A. A. Sadovoi and N. M. Chulkov, "Distribution of kinetic energy dissipation into thermal energy over a spherical shell thickness because of viscosity," in: Calculation Algorithms of Engineering and N. M. Chulkov, "Inertial convergence of cylindrical and spherical shells of incompressible

Alexandrov, Victor

474

The National Ignition Facility (NIF) and the National Ignition Campaign (NIC)  

SciTech Connect (OSTI)

The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). NIF construction was certified by the Department of Energy as complete on March 27, 2009. NIF, a 192-beam Nd:glass laser facility, will ultimately produce 1.8-MJ, 500-TW of 351-nm third-harmonic, ultraviolet light. On March 10, 2009, total 192-beam energy of 1.1 MJ was demonstrated; this is approximately 30 times more energy than ever produced in an ICF laser system. The principal goal of NIF is to achieve ignition of a deuterium-tritium (DT) fuel capsule and provide access to HED physics regimes needed for experiments related to national security, fusion energy and broader frontier scientific exploration. NIF experiments in support of indirect-drive ignition began in August 2009. These first experiments represent the next phase of the National Ignition Campaign (NIC). The NIC is a national effort to achieve fusion ignition and is coordinated through a detailed execution plan that includes the science, technology, and equipment. Equipment required for ignition experiments includes diagnostics, a cryogenic target manipulator, and user optics. Participants in this effort include LLNL, General Atomics (GA), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), and the University of Rochester Laboratory for Energetics (LLE). The primary goal for NIC is to have all of the equipment operational, integrated into the facility, and ready to begin a credible ignition campaign in 2010. With NIF now operational, the long-sought goal of achieving self-sustained nuclear fusion and energy gain in the laboratory is much closer to realization. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of Inertial Fusion Energy (IFE) and will likely focus the world's attention on the possibility of an ICF energy option. NIF experiments to demonstrate ignition and gain will use central-hot-spot (CHS) ignition, where a spherical fuel capsule is simultaneously compressed and ignited. The scientific basis for CHS has been intensively developed. Achieving ignition with CHS will open the door for other advanced concepts, such as the use of high-yield pulses of visible wavelength rather than ultraviolet and Fast Ignition concepts. Moreover, NIF will have important scientific applications in such diverse fields as astrophysics, nuclear physics and materials science. The NIC will develop the full set of capabilities required to operate NIF as a major national and international user facility. A solicitation for NIF frontier science experiments is planned for summer 2009. This paper summarizes the design, performance, and status of NIF and plans for the NIF ignition experimental program. A brief summary of the overall NIF experimental program is also presented.

Moses, E

2009-09-17T23:59:59.000Z

475

FY 2009 National Security Technologies, LLC, PER Summary | National...  

National Nuclear Security Administration (NNSA)

Fee Total Fee Earned % 23,150,112 21,529,431 93% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

476

FY 2008 National Security Technologies, LLC, PER Summary | National...  

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

Fee Total Fee Earned % 21,915,495 20,818,340 95% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

477

FY 2006 National Security Technologies, LLC, PER Summary | National...  

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

Fee Total Fee Earned % 5,717,227 5,431,366 85% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

478

FY 2011 National Security Technologies, LLC, PER Summary | National...  

National Nuclear Security Administration (NNSA)

Total Fee Earned % 23,778,080 22,711,395 95.51% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

479

FY 2010 National Security Technologies, LLC, PER Summary | National...  

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

Total Fee Earned % 21,963,057 19,293,505 87.8% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

480

FY 2007 National Security Technologies, LLC, PER Summary | National...  

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

Total Fee Earned % 23,060,224 19,264,822 83.5% National Security Technologies, LLC (NSTec), the management and operating contractor for the Nevada National Security Site,...

Note: This page contains sample records for the topic "national spherical torus" 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.


481

PUBLISHED VERSION Coherence imaging of scrape-off-layer and divertor impurity flows in the Mega Amp Spherical  

E-Print Network [OSTI]

Kingdom 3 Plasma Research Laboratory, Australian National University, Canberra, ACT 0200, Australia 4 York

482

Geologic Sequestration The National Energy Technology Laboratory and Los Alamos National Laboratory  

E-Print Network [OSTI]

Geologic Sequestration The National Energy Technology Laboratory and Los Alamos National Laboratory) and the National Energy Technology Laboratory (NETL) are collaborating to develop a national plan to determine

483

National Synchrotron Light Source  

ScienceCinema (OSTI)

A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

BNL

2009-09-01T23:59:59.000Z

484

National Security Initiatives | ORNL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn Cyber Security Nuclear Forensics Bioinformatics

485

News | Argonne National Laboratory  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn CyberNeutronsNew

486

Sandia National Laboratories: sputtering  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbineredox-activeNational Solar Thermal

487

Sandia National Laboratories: tsunami  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbineredox-activeNational SolartSSLPV

488

National Mining Association Experimental Determination  

E-Print Network [OSTI]

National Mining Association Experimental Determination of Radon Fluxes over Water #12;Introduction research funded by the National Mining Association (NMA) regarding radon fluxes from water surfaces surfaces at uranium recovery operations are insignificant and approximate background soil fluxes for most

489

The National Transport Data Framework  

E-Print Network [OSTI]

................................................................................................................ 14 NTDF PROTOTYPE ............................................................................................................................... 14 NTDF ARCHITECTURE... ................................................................................................................................. 27 RESOURCING .......................................................................................................................................... 27 ? The National Transport Data Framework March 2008 ? Page 2 SUSTAINABILITY...

Landshoff, Peter Vincent; Polak, John

2008-08-18T23:59:59.000Z

490

National Algal Biofuels Technology Roadmap  

E-Print Network [OSTI]

National Algal Biofuels Technology Roadmap MAY 2010 BIOMASS PROGRAM #12;#12;U.S. DOE 2010. National Algal Biofuels Technology Roadmap. U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Biomass Program. Visit http://biomass.energy.gov for more information National Algal Biofuels

491

Research Report National inventory of  

E-Print Network [OSTI]

Research Report National inventory of woodland and trees (1995­99): methodology #12;#12;i National inventory of woodland and trees (1995­99): methodology Steve Smith, Justin Gilbert, Graham Bull, Simon). National inventory of woodland and trees (1995­99): methodology. Forestry Commission Research Report

492

National Forest Inventory of Great  

E-Print Network [OSTI]

National Forest Inventory of Great Britain Survey Manual #12;2 Remember to Save your Edit Session Regularly, Validate the information and Backup the Data NFI Survey Manual National Forest Inventory Survey in the surveys contributes to the National Forest Inventory (NFI) of Great Britain. With the information from

493

Mensuration protocol National Forest Inventory  

E-Print Network [OSTI]

NFI: Mensuration protocol for the National Forest Inventory June 2010 E. D. Mackie, R. W. Matthews and A. Brewer1 FR Biometrics Division 1 IFOS, Forestry Commission #12;National Forest Inventory (NFI or square boundary. In the case of a section 2 #12;National Forest Inventory (NFI): Mensuration Protocol

494

NATIONAL MUSEUM OF NATURAL HISTORY  

E-Print Network [OSTI]

NATIONAL MUSEUM OF NATURAL HISTORY Annual Report 2004 #12;2 NATIONAL MUSEUM OF NATURAL HISTORY · www.mnh.si.edu The revitalization of the National Museum of Natural History proceeded at a rapid pace, innovation and solid groundwork for future growth. The Museum's agenda is an active one. As with any

Mathis, Wayne N.

495

Increase in the energy density of the pinch plasma in 3D implosion of quasi-spherical wire arrays  

SciTech Connect (OSTI)

Results are presented from experimental studies of the characteristics of the soft X-ray (SXR) source formed in the implosion of quasi-spherical arrays made of tungsten wires and metalized kapron fibers. The experiments were carried out at the Angara-5-1 facility at currents of up to 3 MA. Analysis of the spatial distribution of hard X-ray emission with photon energies above 20 keV in the pinch images taken during the implosion of quasi-spherical tungsten wire arrays (QTWAs) showed that a compact quasi-spherical plasma object symmetric with respect to the array axis formed in the central region of the array. Using a diffraction grazing incidence spectrograph, spectra of SXR emission with wavelengths of 20400 from the central, axial, and peripheral regions of the emission source were measured with spatial resolutions along the array radius and height in the implosion of QTWAs. It is shown that the emission spectra of the SXR sources formed under the implosion of quasi-spherical and cylindrical tungsten wire arrays at currents of up to 3 MA have a maximum in the wavelength range of 50150 . It is found that, during the implosion of a QTWA with a profiled linear mass, a redistribution of energy in the emission spectrum takes place, which indicates that, during 3D implosion, the energy of longitudinal motion of the array material additionally contributes to the radiation energy. It is also found that, at close masses of the arrays and close values of the current in the range of 2.4{sup ?3} MA, the average energy density in the emission source formed during the implosion of a quasi-spherical wire array is larger by a factor of 7 than in the source formed during the implosion of a cylindrical wire array. The experimental data were compared with results of 3D simulations of plasma dynamics and radiation generation during the implosion of quasi-spherical wire arrays with a profiled mass by using the MARPLE-3D radiative magnetohydrodynamic code, developed at the Keldysh Institute of Applied Mathematics, Russian Academy of Sciences.

Aleksandrov, V. V., E-mail: alexvv@triniti.ru [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Gasilov, V. A. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Grabovski, E. V.; Gritsuk, A. N., E-mail: griar@triniti.ru; Laukhin, Ya. N.; Mitrofanov, K. N.; Oleinik, G. M. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Olkhovskaya, O. G. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Sasorov, P. V.; Smirnov, V. P.; Frolov, I. N. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Shevelko, A. P. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

2014-12-15T23:59:59.000Z

496

Analysis of low-pressure dc breakdown in nitrogen between two spherical iron electrodes  

SciTech Connect (OSTI)

The influence of afterglow period {tau}, voltage increase rate k, and electrode gap d on breakdown voltage U{sub b} for a nitrogen-filled tube with spherical electrodes of diameter D>>d and p=6.5 mbar has been investigated. The data for the breakdown voltage were obtained for the case when there is a presence of N({sup 4}S) atoms, which release secondary electrons via recombination on the cathode. By fitting the experimental data of breakdown voltage mean values as a function of the voltage increase rate, the static breakdown voltages for afterglow periods of 15 and 100 s were estimated. The electrical field as a function of the electrode gap using breakdown voltage mean values was also determined. It is shown that experimental results of the breakdown voltage mean value as a function of pd in the interval of d from 0.82 to 1.62 mm can be very well described with Paschen's law, valid for the case of parallel-plate electrodes.

Pejovic, Momcilo M.; Nesic, Nikola T.; Pejovic, Milic M. [Faculty of Electronic Engineering, University of Nis, P.O. Box 73, 18001 (Serbia and Montenegro)

2006-02-15T23:59:59.000Z

497

Literature Review of Spherical Resorcinol-Formaldehyde for Cesium Ion Exchange  

SciTech Connect (OSTI)

The current report summarizes work performed throughout the scientific community and DOE complex as reported in the open literature and DOE-sponsored reports to evaluate the Cs+ ion exchange (CIX) characteristics of SRF resin. King (2007) completed a similar literature review in support of material selection for the Small Column Ion Exchange (SCIX) project. Josephson et al. (2010) and Sams et al. (2009) provided a similar brief review of SRF CIX for the near-tank Cs+ removal (NTCR) project. Thorson (2008a) documented the basis for recommending SRF over SuperLigTM 644 as the primary CIX resin in the WTP. The current review expands on previous work, summarizes additional work completed to date, and provides a broad view of the literature without focusing on a specific column system. Although the focus of the current review is the SRF resin, many cited references include multiple materials such as the non-spherical GGRF and SuperLigTM 644 organic resins and crystalline silicotitanate (CST) IONSIVTM IE-911, a non-elutable inorganic material. This report summarizes relevant information provided in the literature.

Brown, Garrett N.

2014-09-30T23:59:59.000Z

498

Electrohydrodynamic migration of a spherical drop in a general quadratic flow  

E-Print Network [OSTI]

We investigate the motion of a spherical drop in a general quadratic flow acted upon by an arbitrarily oriented externally applied uniform electric field. The drop and media are considered to be leaky dielectrics. The flow field affects the distribution of charges on the drop surface, which leads to alteration in the electric field, thereby affecting the velocity field through the Maxwell stress on the fluid-fluid interface. The two-way coupled electrohydrodynamics is central towards dictating the motion of the drop in the flow field. We analytically address the electric potential distribution and Stokesian flow field in and around the drop in a general quadratic flow for small electric Reynolds number (which is the ratio of the charge relaxation time scale to the convective time scale). As a special case, we consider a drop in an unbounded cylindrical Poiseuille flow and show that, an otherwise absent, cross-stream drop migration may be obtained in the presence of a uniform electric field. Depending on the d...

Mandal, Shubhadeep; Chakraborty, Suman

2015-01-01T23:59:59.000Z

499

Beam emission spectroscopy turbulence imaging system for the MAST spherical tokamak  

SciTech Connect (OSTI)

A new beam emission spectroscopy turbulence imaging system has recently been installed onto the MAST spherical tokamak. The system utilises a high-throughput, direct coupled imaging optics, and a single large interference filter for collection of the Doppler shifted D{sub {alpha}} emission from the {approx}2 MW heating beam of {approx}70 keV injection energy. The collected light is imaged onto a 2D array detector with 8 x 4 avalanche photodiode sensors which is incorporated into a custom camera unit to perform simultaneous 14-bit digitization at 2 MHz of all 32 channels. The array is imaged at the beam to achieve a spatial resolution of {approx}2 cm in the radial (horizontal) and poloidal (vertical) directions, which is sufficient for detection of the ion-scale plasma turbulence. At the typical photon fluxes of {approx}10{sup 11} s{sup -1} the achieved signal-to-noise ratio of {approx}300 at the 0.5 MHz analogue bandwidth is sufficient for detection of relative density fluctuations at the level of a few 0.1%. The system is to be utilised for the study of the characteristics of the broadband, ion-scale turbulence, in particular its interaction with flow shear, as well as coherent fluctuations due to various types of MHD activity.

Field, A. R.; Gaffka, R.; Shibaev, S. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Dunai, D.; Kiss, I.; Meszaros, B.; Krizsanoczi, T.; Zoletnik, S. [KFKI-RMKI, Association EURATOM, P.O. Box 49, H-1525 Budapest (Hungary); Ghim, Y.-C. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford (United Kingdom)

2012-01-15T23:59:59.000Z

500

The jump-off velocity of an impulsively loaded spherical shell  

SciTech Connect (OSTI)

We consider a constant temperature spherical shell of isotropic, homogeneous, linearly elastic material with density {rho} and Lame coefficients {lambda} and {mu}. The inner and outer radii of the shell are r{sub i} and r{sub o}, respectively. We assume that the inside of the shell is a void. On the outside of the shell, we apply a uniform, time-varying pressure p(t). We also assume that the shell is initially at rest. We want to compute the jump-off time and velocity of the pressure wave, which are the first time after t = 0 at which the pressure wave from the outer surface reaches the inner surface. This analysis computes the jump-off velocity and time for both compressible and incompressible materials. This differs substantially from [3], where only incompressible materials are considered. We will consider the behavior of an impulsively loaded, exponentially decaying pressure wave p(t) = P{sub 0{sup e}}{sup -{alpha}t}, where {alpha} {ge} 0. We notice that a constant pressure wave P(t) = P{sub 0} is a special case ({alpha} = 0) of a decaying pressure wave. Both of these boundary conditions are considered in [3].

Chabaud, Brandon M. [Los Alamos National Laboratory; Brock, Jerry S. [Los Alamos National Laboratory

2012-04-13T23:59:59.000Z