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1

Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps...  

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

Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps Development of Chemical Kinetic Models for Lean NOx Traps Modeling the Regeneration Chemistry of Lean NOx Traps...

2

Investigation of Aging Mechanisms in Lean NOx Traps | Department...  

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

"Mega" Merit Review 2008 on February 25, 2008 in Bethesda, Maryland. merit08johnson.pdf More Documents & Publications Investigation of Aging Mechanisms in Lean NOx Traps...

3

Freely floating structures trapping time-harmonic water waves (revisited)  

E-Print Network (OSTI)

We study the coupled small-amplitude motion of the mechanical system consisting of infinitely deep water and a structure immersed in it. The former is bounded above by a free surface, whereas the latter is formed by an arbitrary finite number of surface-piercing bodies floating freely. The mathematical model of time-harmonic motion is a spectral problem in which the frequency of oscillations serves as the spectral parameter. It is proved that there exist axisymmetric structures consisting of $N \\geq 2$ bodies; every structure has the following properties: (i) a time-harmonic wave mode is trapped by it; (ii) some of its bodies (may be none) are motionless, whereas the rest of the bodies (may be none) are heaving at the same frequency as water. The construction of these structures is based on a generalization of the semi-inverse procedure applied earlier for obtaining trapping bodies that are motionless although float freely.

Nikolay Kuznetsov; Oleg Motygin

2014-10-22T23:59:59.000Z

4

Time in quantum mechanics  

E-Print Network (OSTI)

OF CONTENTS I. INTRODUCTION II. HISTORICAL DEVELOPMENT A. Classical Mechanics B. Quantum Theory . C. The Problem 3 4 6 III. TIME ATOMS AND DISCRETE TIME A. The Earliest Applications of Atomistic and Discrete Time . . . . . B. The Radiating Electron... . C. Quantum Field Theory 8 10 l2 IV. TIME OPERATOR FORMULATIONS 16 A. Advocates Against a Time Operator . B. The Possibility of a Time Operator C, Advocates in Favor of a Time Operator D. A Restricted Time Delay Operator: Scattering Theory...

Chapin, Kimberly R.

2012-06-07T23:59:59.000Z

5

Spin Self-Rephasing and Very Long Coherence Times in a Trapped Atomic Ensemble  

SciTech Connect

We perform Ramsey spectroscopy on the ground state of ultracold {sup 87}Rb atoms magnetically trapped on a chip in the Knudsen regime. Field inhomogeneities over the sample should limit the 1/e contrast decay time to about 3 s, while decay times of 58{+-}12 s are actually observed. We explain this surprising result by a spin self-rephasing mechanism induced by the identical spin rotation effect originating from particle indistinguishability. We propose a theory of this synchronization mechanism and obtain good agreement with the experimental observations. The effect is general and may appear in other physical systems.

Deutsch, C.; Reinhard, F.; Schneider, T.; Laloee, F.; Reichel, J. [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France); Ramirez-Martinez, F.; Lacroute, C.; Rosenbusch, P. [LNE-SYRTE, Observatoire de Paris, UPMC, CNRS, 61 av de l'Observatoire, 75014 Paris (France); Fuchs, J. N.; Piechon, F. [Laboratoire de Physique des Solides, CNRS UMR 8502, Univ. Paris-Sud, 91405 Orsay (France)

2010-07-09T23:59:59.000Z

6

Drunken robber, tipsy cop: First passage times, mobile traps, and Hopf bifurcations  

E-Print Network (OSTI)

For a random walk on a confined one-dimensional domain, we consider mean first passage times (MFPT) in the presence of a mobile trap. The question we address is whether a mobile trap can improve capture times over a stationary trap. We consider two scenarios: a randomly moving trap and an oscillating trap. In both cases, we find that a stationary trap actually performs better (in terms of reducing expected capture time) than a very slowly moving trap; however, a trap moving sufficiently fast performs better than a stationary trap. We explicitly compute the thresholds that separate the two regimes. In addition, we find a surprising relation between the oscillating trap problem and a moving-sink problem that describes reduced dynamics of a single spike in a certain regime of the Gray-Scott model. Namely, the above-mentioned threshold corresponds precisely to a Hopf bifurcation that induces oscillatory motion in the location of the spike. We use this correspondence to prove the uniqueness of the Hopf bifurcation.

Justin C. Tzou; Shuangquan Xie; Theodore Kolokolnikov

2014-10-03T23:59:59.000Z

7

High-k shallow traps observed by charge pumping with varying discharging times  

SciTech Connect

In this paper, we investigate the influence of falling time and base level time on high-k bulk shallow traps measured by charge pumping technique in n-channel metal-oxide-semiconductor field-effect transistors with HfO{sub 2}/metal gate stacks. N{sub T}-V{sub high} {sub level} characteristic curves with different duty ratios indicate that the electron detrapping time dominates the value of N{sub T} for extra contribution of I{sub cp} traps. N{sub T} is the number of traps, and I{sub cp} is charge pumping current. By fitting discharge formula at different temperatures, the results show that extra contribution of I{sub cp} traps at high voltage are in fact high-k bulk shallow traps. This is also verified through a comparison of different interlayer thicknesses and different Ti{sub x}N{sub 1?x} metal gate concentrations. Next, N{sub T}-V{sub high} {sub level} characteristic curves with different falling times (t{sub falling} {sub time}) and base level times (t{sub base} {sub level}) show that extra contribution of I{sub cp} traps decrease with an increase in t{sub falling} {sub time}. By fitting discharge formula for different t{sub falling} {sub time}, the results show that electrons trapped in high-k bulk shallow traps first discharge to the channel and then to source and drain during t{sub falling} {sub time}. This current cannot be measured by the charge pumping technique. Subsequent measurements of N{sub T} by charge pumping technique at t{sub base} {sub level} reveal a remainder of electrons trapped in high-k bulk shallow traps.

Ho, Szu-Han; Chen, Ching-En; Tseng, Tseung-Yuen [Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang@mail.phys.nsysu.edu.tw [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Tainan, Taiwan (China); Lu, Ying-Hsin; Lo, Wen-Hung; Tsai, Jyun-Yu; Liu, Kuan-Ju [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Wang, Bin-Wei; Cao, Xi-Xin [Department of Embedded System Engineering, Peking University, Beijing, P.R.China (China); Chen, Hua-Mao [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, Taiwan (China); Cheng, Osbert; Huang, Cheng-Tung; Chen, Tsai-Fu [Device Department, United Microelectronics Corporation, Tainan Science Park, Taiwan (China)

2013-11-07T23:59:59.000Z

8

Extended Coherence Time on the Clock Transition of Optically Trapped Rubidium  

SciTech Connect

Optically trapped ensembles are of crucial importance for frequency measurements and quantum memories but generally suffer from strong dephasing due to inhomogeneous density and light shifts. We demonstrate a drastic increase of the coherence time to 21 s on the magnetic field insensitive clock transition of {sup 87}Rb by applying the recently discovered spin self-rephasing [C. Deutsch et al., Phys. Rev. Lett. 105, 020401 (2010)]. This result confirms the general nature of this new mechanism and thus shows its applicability in atom clocks and quantum memories. A systematic investigation of all relevant frequency shifts and noise contributions yields a stability of 2.4x10{sup -11{tau}-1/2}, where {tau} is the integration time in seconds. Based on a set of technical improvements, the presented frequency standard is predicted to rival the stability of microwave fountain clocks in a potentially much more compact setup.

Kleine Buening, G.; Will, J.; Ertmer, W.; Rasel, E.; Klempt, C. [Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Welfengarten 1, 30167 Hannover (Germany); Arlt, J. [QUANTOP, Institut for Fysik og Astronomi, Aarhus Universitet, Ny Munkegade 120, 8000 Aarhus C (Denmark); Ramirez-Martinez, F.; Rosenbusch, P. [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 av de l'Observatoire, 75014 Paris (France); Piechon, F. [Laboratoire de Physique des Solides, CNRS, UMR 8502, Univ. Paris-Sud, 91405 Orsay (France)

2011-06-17T23:59:59.000Z

9

STOPPING TIMES IN QUANTUM MECHANICS  

E-Print Network (OSTI)

(Stinespring, Kraus). 3". Time-dependant case General time evolution of an open quantum sys- tem = (Pt)t0

Attal, Stéphane

10

Long-term Variations of CO2 Trapped in Different Mechanisms in Deep Saline Formations: A Case Study of the Songliao Basin, China  

SciTech Connect

The geological storage of CO{sub 2} in deep saline formations is increasing seen as a viable strategy to reduce the release of greenhouse gases to the atmosphere. There are numerous sedimentary basins in China, in which a number of suitable CO{sub 2} geologic reservoirs are potentially available. To identify the multi-phase processes, geochemical changes and mineral alteration, and CO{sub 2} trapping mechanisms after CO{sub 2} injection, reactive geochemical transport simulations using a simple 2D model were performed. Mineralogical composition and water chemistry from a deep saline formation of Songliao Basin were used. Results indicate that different storage forms of CO{sub 2} vary with time. In the CO{sub 2} injection period, a large amount of CO{sub 2} remains as a free supercritical phase (gas trapping), and the amount dissolved in the formation water (solubility trapping) gradually increases. Later, gas trapping decreases, solubility trapping increases significantly due to migration and diffusion of the CO{sub 2} plume, and the amount trapped by carbonate minerals increases gradually with time. The residual CO{sub 2} gas keeps dissolving into groundwater and precipitating carbonate minerals. For the Songliao Basin sandstone, variations in the reaction rate and abundance of chlorite, and plagioclase composition affect significantly the estimates of mineral alteration and CO{sub 2} storage in different trapping mechanisms. The effect of vertical permeability and residual gas saturation on the overall storage is smaller compared to the geochemical factors. However, they can affect the spatial distribution of the injected CO{sub 2} in the formations. The CO{sub 2} mineral trapping capacity could be in the order of ten kilogram per cubic meter medium for the Songliao Basin sandstone, and may be higher depending on the composition of primary aluminosilicate minerals especially the content of Ca, Mg, and Fe.

Zhang, Wei; Li, Yilian; Xu, Tianfu; Cheng, Huilin; Zheng, Yan; Xiong, Peng

2008-06-10T23:59:59.000Z

11

On Time in Quantum Mechanics  

E-Print Network (OSTI)

Although time measurements are routinely performed in laboratories, their theoretical description is still an open problem. Correspondingly, the status of the energy-time uncertainty relation is unsettled. In the first part of this work the necessity of positive operator valued measures (POVM) as descriptions of every quantum experiment is reviewed, as well as the suggestive role played by the probability current in time measurements. Furthermore, it is shown that no POVM exists, which approximately agrees with the probability current on a very natural set of wave functions; nevertheless, the choice of the set is crucial, and on more restrictive sets the probability current does provide a good arrival time prediction. Some ideas to experimentally detect quantum effects in time measurements are discussed. In the second part of the work the energy-time uncertainty relation is considered, in particular for a model of alpha decay for which the variance of the energy can be calculated explicitly, and the variance of time can be estimated. This estimate is tight for systems with long lifetimes, in which case the uncertainty relation is shown to be satisfied. Also the linewidth-lifetime relation is shown to hold, but contrary to the common expectation, it is found that the two relations behave independently, and therefore it is not possible to interpret one as a consequence of the other. To perform the mentioned analysis quantitative scattering estimates are necessary. To this end, bounds of the form $\\|1_Re^{-iHt}\\psi\\|_2^2 \\leq C t^{-3}$ have been derived, where $\\psi$ denotes the initial state, $H$ the Hamiltonian, $R$ a positive constant, and $C$ is explicitly known. As intermediate step, bounds on the derivatives of the $S$-matrix in the form $\\|1_K S^{(n)}\\|_\\infty \\leq C_{n,K} $ have been established, with $n=1,2,3$, and the constants $C_{n,K}$ explicitly known.

Nicola Vona

2014-03-11T23:59:59.000Z

12

Marine Mechanical Engineer Full Time Position Wanted: Marine Mechanical Engineer  

E-Print Network (OSTI)

the following; Marine Systems Design and Engineering (fuel, water, HVAC, compressed air, exhaust, lube oil, etcMarine Mechanical Engineer Full Time Position Wanted: Marine Mechanical Engineer Boksa Marine Design, Inc. is a growing naval architecture and marine engineering firm specializing in the design

Eustice, Ryan

13

Quantum mechanics and the time travel paradox  

E-Print Network (OSTI)

The closed causal chains arising from backward time travel do not lead to paradoxes if they are self consistent. This raises the question as to how physics ensures that only self-consistent loops are possible. We show that, for one particular case at least, the condition of self consistency is ensured by the interference of quantum mechanical amplitudes associated with the loop. If this can be applied to all loops then we have a mechanism by which inconsistent loops eliminate themselves.

David T. Pegg

2005-06-17T23:59:59.000Z

14

Vibrational relaxation of trapped molecules  

Science Journals Connector (OSTI)

Vibrational relaxation of trapped molecules due to collisions with cold atoms is investigated using the results of quantum-mechanical scattering calculations. Trap loss is analyzed using an exactly solvable kinetic model that includes direct collisional quenching and an indirect process of vibrational predissociation. At low atom density, the relaxation is due primarily to collisional quenching. At high atom density, the relaxation involves additional time scales due to the formation and decay of van der Waals complexes. It is shown that the most weakly bound state of the van der Waals complex for a given diatomic vibrational level controls the relaxation at all atom densities. Possible experiments using trapped molecules are discussed.

R. C. Forrey; V. Kharchenko; N. Balakrishnan; A. Dalgarno

1999-03-01T23:59:59.000Z

15

Influence of interlayer trapping and detrapping mechanisms on the electrical characterization of hafnium oxide/silicon nitride stacks on silicon  

SciTech Connect

Al/HfO{sub 2}/SiN{sub x}:H/n-Si metal-insulator-semiconductor capacitors have been studied by electrical characterization. Films of silicon nitride were directly grown on n-type silicon substrates by electron cyclotron resonance assisted chemical vapor deposition. Silicon nitride thickness was varied from 3 to 6.6 nm. Afterwards, 12 nm thick hafnium oxide films were deposited by the high-pressure sputtering approach. Interface quality was determined by using current-voltage, capacitance-voltage, deep-level transient spectroscopy (DLTS), conductance transients, and flatband voltage transient techniques. Leakage currents followed the Poole-Frenkel emission model in all cases. According to the simultaneous measurement of the high and low frequency capacitance voltage curves, the interface trap density obtained for all the samples is in the 10{sup 11} cm{sup -2} eV{sup -1} range. However, a significant increase in this density of about two orders of magnitude was obtained by DLTS for the thinnest silicon nitride interfacial layers. In this work we probe that this increase is an artifact that must be attributed to traps existing at the HfO{sub 2}/SiN{sub x}:H intralayer interface. These traps are more easily charged or discharged as this interface comes near to the substrate, that is, as thinner the SiN{sub x}:H interface layer is. The trapping/detrapping mechanism increases the capacitance transient and, in consequence, the DLTS measurements have contributions not only from the insulator/substrate interface but also from the HfO{sub 2}/SiN{sub x}:H intralayer interface.

Garcia, H.; Duenas, S.; Castan, H.; Gomez, A.; Bailon, L. [Departamento de Electricidad y Electronica, E.T.S.I. Telecomunicacion, Universidad de Valladolid, Campus 'Miguel Delibes', 47011 Valladolid (Spain); Toledano-Luque, M.; Prado, A. del; Martil, I.; Gonzalez-Diaz, G. [Departamento de Fisica Aplicada III (Electricidad y Electronica), Facultad de Ciencias Fisicas, Universidad Complutense, 28040 Madrid (Spain)

2008-11-01T23:59:59.000Z

16

Hydrocarbon trapping mechanisms in the Miller Creek area of the Powder River Basin, Wyoming  

E-Print Network (OSTI)

'' 1975 43'W'79 ABSTRACT Hydrocarbon Trapoing Mechanisms in the Miller Creek Area of the Powder River Basin, Wyoming. (May 1975) Jennifer Ann Armstrong, B. S. , University of Texas at Austin Chairman of Advisory Committee: 17r. Robert. R. Berg...

Armstrong, Jennifer Ann

1975-01-01T23:59:59.000Z

17

Long storage time of collective coherence in an optically trapped Bose-Einstein condensate Yutaka Yoshikawa,1,2,* Kazuyuki Nakayama,2  

E-Print Network (OSTI)

of condensates, a high conversion efficiency of over 70% and a long storage time of about 0.13 ms were achievedLong storage time of collective coherence in an optically trapped Bose-Einstein condensate Yutaka- Einstein condensate Phys. Rev. Lett. 99, 220407 2007 . This time we report the drastic improvement

Torii, Yoshio

18

Nonlinear integrable ion traps  

SciTech Connect

Quadrupole ion traps can be transformed into nonlinear traps with integrable motion by adding special electrostatic potentials. This can be done with both stationary potentials (electrostatic plus a uniform magnetic field) and with time-dependent electric potentials. These potentials are chosen such that the single particle Hamilton-Jacobi equations of motion are separable in some coordinate systems. The electrostatic potentials have several free adjustable parameters allowing for a quadrupole trap to be transformed into, for example, a double-well or a toroidal-well system. The particle motion remains regular, non-chaotic, integrable in quadratures, and stable for a wide range of parameters. We present two examples of how to realize such a system in case of a time-independent (the Penning trap) as well as a time-dependent (the Paul trap) configuration.

Nagaitsev, S.; /Fermilab; Danilov, V.; /SNS Project, Oak Ridge

2011-10-01T23:59:59.000Z

19

detonation trap  

Science Journals Connector (OSTI)

detonation trap [It prevents a detonation initiated in one part of a system...] ? Detonationsfang m, Detonationsfänger m

2014-08-01T23:59:59.000Z

20

Quantum Mechanics and Discrete Time from "Timeless" Classical Dynamics  

E-Print Network (OSTI)

We study classical Hamiltonian systems in which the intrinsic proper time evolution parameter is related through a probability distribution to the physical time, which is assumed to be discrete. - This is motivated by the ``timeless'' reparametrization invariant model of a relativistic particle with two compactified extradimensions. In this example, discrete physical time is constructed based on quasi-local observables. - Generally, employing the path-integral formulation of classical mechanics developed by Gozzi et al., we show that these deterministic classical systems can be naturally described as unitary quantum mechanical models. The emergent quantum Hamiltonian is derived from the underlying classical one. It is closely related to the Liouville operator. We demonstrate in several examples the necessity of regularization, in order to arrive at quantum models with bounded spectrum and stable groundstate.

H. -T. Elze

2003-07-03T23:59:59.000Z

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


21

Collisionless Weibel shocks: Full formation mechanism and timing  

SciTech Connect

Collisionless shocks in plasmas play an important role in space physics (Earth's bow shock) and astrophysics (supernova remnants, relativistic jets, gamma-ray bursts, high energy cosmic rays). While the formation of a fluid shock through the steepening of a large amplitude sound wave has been understood for long, there is currently no detailed picture of the mechanism responsible for the formation of a collisionless shock. We unravel the physical mechanism at work and show that an electromagnetic Weibel shock always forms when two relativistic collisionless, initially unmagnetized, plasma shells encounter. The predicted shock formation time is in good agreement with 2D and 3D particle-in-cell simulations of counterstreaming pair plasmas. By predicting the shock formation time, experimental setups aiming at producing such shocks can be optimised to favourable conditions.

Bret, A. [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Stockem, A. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal); Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Narayan, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51 Cambridge, Massachusetts 02138 (United States); Silva, L. O. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal)

2014-07-15T23:59:59.000Z

22

Effect of trapped electron on the dust ion acoustic waves in dusty plasma using time fractional modified Korteweg-de Vries equation  

SciTech Connect

The time fractional modified Korteweg-de Vries (TFMKdV) equation is solved to study the nonlinear propagation of small but finite amplitude dust ion-acoustic (DIA) solitary waves in un-magnetized dusty plasma with trapped electrons. The plasma is composed of a cold ion fluid, stationary dust grains, and hot electrons obeying a trapped electron distribution. The TFMKdV equation is derived by using the semi-inverse and Agrawal's methods and then solved by the Laplace Adomian decomposition method. Our results show that the amplitude of the DIA solitary waves increases with the increase of time fractional order ?, the wave velocity v{sub 0}, and the population of the background free electrons ?. However, it is vice-versa for the deviation from isothermality parameter b, which is in agreement with the result obtained previously.

Nazari-Golshan, A. [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)] [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Nourazar, S. S. [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of) [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Department of Mechanical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

2013-10-15T23:59:59.000Z

23

Trapping Coyotes  

E-Print Network (OSTI)

Coyotes cause millions of dollars of damage yearly to livestock and crops in Texas. The leaflet explains coyote habits and the types of trap set, such as scent posts, dirt holes, and trail and carcass sets. The variety of traps available and how...

Texas Wildlife Services

2008-04-15T23:59:59.000Z

24

Magnetic trap for thulium atoms  

SciTech Connect

For the first time ultra-cold thulium atoms were trapped in a magnetic quadrupole trap with a small field gradient (20 Gs cm{sup -1}). The atoms were loaded from a cloud containing 4x10{sup 5} atoms that were preliminarily cooled in a magneto-optical trap to the sub-Doppler temperature of 80 {mu}K. As many as 4x10{sup 4} atoms were trapped in the magnetic trap at the temperature of 40 {mu}K. By the character of trap population decay the lifetime of atoms was determined (0.5 s) and an upper estimate was obtained for the rate constant of inelastic binary collisions for spin-polarised thulium atoms in the ground state (g{sub in} < 10{sup -11}cm{sup 3} s{sup -1}). (magnetic traps)

Sukachev, D D; Sokolov, A V; Chebakov, K A; Akimov, A V; Kolachevskii, N N; Sorokin, Vadim N [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2011-08-31T23:59:59.000Z

25

Mechanism(s) of Ni Sorption on Al-Hydroxy-Interlayered Vermiculite Using Time-Resolved EXAFS  

E-Print Network (OSTI)

Mechanism(s) of Ni Sorption on Al-Hydroxy-Interlayered Vermiculite Using Time-Resolved EXAFS D. R role in retaining these compounds. However, little research has been done to investigate the sorption of Ni when reacted with Al-pillared vermiculite over various times. The sorption of Ni increased when

Sparks, Donald L.

26

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions  

SciTech Connect

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

Gulyuz, Kerim; Stedwell, Corey N.; Wang Da; Polfer, Nick C. [Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611 (United States)

2011-05-15T23:59:59.000Z

27

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions  

Science Journals Connector (OSTI)

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photondissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources an electrospray ionization source as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection a reduced pressure (?10?5 Torr) quadrupoleion trap (QIT) for OPOirradiation and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study we implemented this setup in the study of protonated tryptophan TrpH+ as well as collision-induced dissociation products of this protonated amino acid[W. K. Mino Jr. K. Gulyuz D. Wang C. N. Stedwell and N. C. Polfer J. Phys. Chem. Lett.2 299 (2011)]. Here we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

Kerim Gulyuz; Corey N. Stedwell; Da Wang; Nick C. Polfer

2011-01-01T23:59:59.000Z

28

PHYSICAL REVIEW E 84, 041928 (2011) Different mechanics of snap-trapping in the two closely related carnivorous plants  

E-Print Network (OSTI)

water content resulting from osmotic pressure, which may reach 1 MPa. Turgor pressure variations in so-called motor cells can actuate organ movement, as single motor cells may undergo a 25% volume change within 1 s and hence can effect cell stiffness in a short time [5]. Groups of antagonistic motor cells in "hinges

29

Incentive Mechanisms for Internet Congestion Management: Fixed-Budget Rebate Versus Time-of-Day Pricing  

E-Print Network (OSTI)

Mobile data traffic has been steadily rising in the past years. This has generated a significant interest in the deployment of incentive mechanisms to reduce peak-time congestion. Typically, the design of these mechanisms ...

Loiseau, Patrick

30

Cryogenic Ion Trapping Systems with Surface-Electrode Traps  

E-Print Network (OSTI)

We present two simple cryogenic RF ion trap systems in which cryogenic temperatures and ultra high vacuum pressures can be reached in as little as 12 hours. The ion traps are operated either in a liquid helium bath cryostat or in a low vibration closed cycle cryostat. The fast turn around time and availability of buffer gas cooling made the systems ideal for testing surface-electrode ion traps. The vibration amplitude of the closed cycled cryostat was found to be below 106 nm. We evaluated the systems by loading surface-electrode ion traps with $^{88}$Sr$^+$ ions using laser ablation, which is compatible with the cryogenic environment. Using Doppler cooling we observed small ion crystals in which optically resolved ions have a trapped lifetime over 2500 minutes.

P. B. Antohi; D. Schuster; G. M. Akselrod; J. Labaziewicz; Y. Ge; Z. Lin; W. S. Bakr; I. L. Chuang

2008-07-29T23:59:59.000Z

31

Interaction of trapped ions with trapped atoms  

E-Print Network (OSTI)

In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

Grier, Andrew T. (Andrew Todd)

2011-01-01T23:59:59.000Z

32

Tracking and imaging of dynamic objects in scattering media by time-reversed adapted-perturbation (TRAP) optical focusing  

E-Print Network (OSTI)

The ability to steer light propagation inside scattering media has long been sought-after due to its potential widespread applications. To form optical foci inside scattering media, the only feasible strategy is to guide photons by using either implanted or virtual guide stars. However, all of these guide stars must be introduced extrinsically, either invasively or by physical contact, limiting the scope of their application. Here, we focus light inside scattering media by employing intrinsic dynamics as guide stars. By time-reversing the perturbed component of the scattered light adaptively, we concentrate light to the origin of the perturbation, where the permittivity varied spontaneously. We demonstrate dynamic light focusing onto moving targets and imaging of a time-variant object obscured by highly scattering media, without invasiveness and physical contact. Anticipated applications include all-weather optical communication with airplanes or satellites, tracking vehicles in thick fogs, and imaging and ph...

Ma, Cheng; Liu, Yan; Wang, Lihong V

2014-01-01T23:59:59.000Z

33

Highlighting the mechanism of the quantum speedup by time-symmetric and relational quantum mechanics  

E-Print Network (OSTI)

Bob hides a ball in one of four drawers. Alice is to locate it. Classically she has to open up to three drawers, quantally just one. The fundamental reason for this quantum speedup is not known. We explain it by extending the usual representation of the quantum algorithm, limited to the process of solving the problem, to the process of setting the problem. The number of the drawer with the ball becomes a unitary transformation of the random outcome of the preparation measurement. This brings in relational quantum mechanics: the extension is with respect to Bob and cannot be with respect to Alice. It would tell her the drawer number before she opens any drawer. To Alice, the projection of the quantum state due to the preparation measurement should be retarded at the end of her search; in the input state of the search, the drawer number is determined to Bob and undetermined to Alice. A second consequence is the emergence of an ambiguity. Either the preparation measurement or the final one required to read the solution selects the solution. For reasons of symmetry, we assume that the selection shares evenly between the two measurements. All is as if Alice, by reading the solution, selected half of the information that specifies the drawer number. This selection leaves the input state to Bob unaltered and projects that to Alice on a state of lower entropy where she knows that half in advance. The quantum algorithm is a sum over histories in each of which Alice knows in advance that the ball is in a pair of drawers and locates it by opening one of the two. More in general, given an oracle problem, this explanation of the speedup predicts the number of queries required to solve it in an optimal quantum way.

Giuseppe Castagnoli

2014-12-11T23:59:59.000Z

34

Reduce Steam Trap Failures at Chambers Works  

E-Print Network (OSTI)

Ultrasonic Inspection At least 2 times per year Steam Trap Surveyor Submit reports to area management, energy team, and reliability engineers for each area every month Steam Trap Team Leader Control Plan ? Process Owner agrees...Reduce Steam Trap Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central...

Kouba, C.

35

Microfabricated Ion Traps  

E-Print Network (OSTI)

Ion traps offer the opportunity to study fundamental quantum systems with high level of accuracy highly decoupled from the environment. Individual atomic ions can be controlled and manipulated with electric fields, cooled to the ground state of motion with laser cooling and coherently manipulated using optical and microwave radiation. Microfabricated ion traps hold the advantage of allowing for smaller trap dimensions and better scalability towards large ion trap arrays also making them a vital ingredient for next generation quantum technologies. Here we provide an introduction into the principles and operation of microfabricated ion traps. We show an overview of material and electrical considerations which are vital for the design of such trap structures. We provide guidance in how to choose the appropriate fabrication design, consider different methods for the fabrication of microfabricated ion traps and discuss previously realized structures. We also discuss the phenomenon of anomalous heating of ions within ion traps, which becomes an important factor in the miniaturization of ion traps.

Marcus D. Hughes; Bjoern Lekitsch; Jiddu A. Broersma; Winfried K. Hensinger

2011-06-28T23:59:59.000Z

36

Trapped Inflation  

SciTech Connect

We analyze a distinctive mechanism for inflation in which particle production slows down a scalar field on a steep potential, and show how it descends from angular moduli in string compactifications. The analysis of density perturbations - taking into account the integrated effect of the produced particles and their quantum fluctuations - requires somewhat new techniques that we develop. We then determine the conditions for this effect to produce sixty e-foldings of inflation with the correct amplitude of density perturbations at the Gaussian level, and show that these requirements can be straightforwardly satisfied. Finally, we estimate the amplitude of the non-Gaussianity in the power spectrum and find a significant equilateral contribution.

Green, Daniel; Horn, Bart; /SLAC /Stanford U., Phys. Dept.; Senatore, Leonardo; /Princeton, Inst. Advanced Study /Harvard U., Phys. Dept. /Harvard-Smithsonian Ctr. Astrophys.; Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.

2009-06-19T23:59:59.000Z

37

REVIEW ARTICLE Optical trapping  

E-Print Network (OSTI)

REVIEW ARTICLE Optical trapping Keir C. Neuman and Steven M. Blocka) Department of Biological ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology--and the measurement of nanometer-level displacements of--optically trapped objects. We review progress

Block, Steven

38

New perspectives in laser analytics: Resonance-enhanced multiphoton ionization in a Paul ion trap combined with a time-of-flight mass spectrometer  

SciTech Connect

A new laser analytical device has been developed that is based on resonance-enhanced multiphoton ionization in the very center of a radio-frequency quadrupole ion trap. Applications in speciation anlaysis of biological and enviromental samples and in materials science will all benefit from laser-optical selectivity in the resonance excitation process, combined with mass-spectropic sensivity which is further enhanced by the ion accumulation and storage capability.

Bisling, Peter; Heger, Hans Joerg; Michaelis, Walfried; Weitkamp, Claus; Zobel, Harald [GKSS-Forschungszentrum Geesthacht GmbH, Postfach 11 60, D-21494 Geesthacht (Germany)

1995-04-01T23:59:59.000Z

39

Standard Model tests with trapped radioactive atoms  

E-Print Network (OSTI)

We review the use of laser cooling and trapping for Standard Model tests, focusing on trapping of radioactive isotopes. Experiments with neutral atoms trapped with modern laser cooling techniques are testing several basic predictions of electroweak unification. For nuclear $\\beta$ decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques have set the best general constraints on non-Standard Model scalar interactions in the first generation of particles. They also have the promise to test whether parity symmetry is maximally violated, to search for tensor interactions, and to search for new sources of time reversal violation. There are also possibilites for exotic particle searches. Measurements of the strength of the weak neutral current can be assisted by precision atomic experiments using traps of small numbers of radioactive atoms, and sensitivity to possible time-reversal violating electric dipole moments can be improved.

J. A. Behr; G. Gwinner

2009-03-04T23:59:59.000Z

40

Scaling self-timed systems powered by mechanical vibration energy harvesting  

Science Journals Connector (OSTI)

Passive energy harvesting from mechanical vibration has wide application in wearable devices and wireless sensors to complement or replace batteries. Energy harvesting efficiency can be increased by eliminating AC/DC conversion. A test chip demonstrating ... Keywords: AC power supply, DRAM, energy harvesting, energy-aware systems, integrated circuits, low-power design, power-on reset, scaling, self-timed

Justin Wenck; Jamie Collier; Jeff Siebert; Rajeevan Amirtharajah

2010-06-01T23:59:59.000Z

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


41

Fast ground-state cooling of mechanical resonators with time-dependent optical cavities  

SciTech Connect

We propose a feasible scheme to cool down a mechanical resonator (MR) in a three-mirror cavity optomechanical system with controllable external optical driving fields. Under the Born-Oppenheimer approximation, the whole dynamics of the mechanical resonator and cavities is reduced to that of a time-dependent harmonic oscillator, whose effective frequency can be controlled through the optical driving fields. The fast cooling of the MR can be realized by controlling the amplitude of the optical driving fields. Significantly, we further show that the ground-state cooling may be achieved via the three-mirror cavity optomechanical system without the resolved sideband condition.

Li Yong [Department of Physics and Center of Theoretical and Computational Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Beijing Computational Science Research Center, Beijing 100084 (China); Wu Lianao [Department of Theoretical Physics and History of Science, The Basque Country University (EHU/UPV), P.O. Box 644, ES-48080 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, ES-48011 Bilbao (Spain); Wang, Z. D. [Department of Physics and Center of Theoretical and Computational Physics, University of Hong Kong, Pokfulam Road (Hong Kong)

2011-04-15T23:59:59.000Z

42

Neutral atom traps.  

SciTech Connect

This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

Pack, Michael Vern

2008-12-01T23:59:59.000Z

43

Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration  

E-Print Network (OSTI)

SHORT TIME SCALE THERMAL MECHANICAL SHOCK WAVE PROPAGATION IN HIGH PERFORMANCE MICROELECTRONIC PACKAGING CONFIGURATION A Thesis by MAHAVIR NAGARAJ Submitted to the Office of Graduate Studies of Texas A&M University... MICROELECTRONIC PACKAGING CONFIGURATION A Thesis by MAHAVIR NAGARAJ Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved as to style and content by: Chii...

Nagaraj, Mahavir

2004-11-15T23:59:59.000Z

44

Structural traps I, tectonic fold traps  

SciTech Connect

This book contains studies of fields that exist because of the presence of an anticline; without the anticline there would be no trap. The fields described in this volume illustrate the complex nature of a trap type that some explorationists mistakenly regard as simple and therefore not worthy of close scrutiny. Anticlinal traps are like all other fields - each has its own peculiar personality. Many of the fields in this volume are sourced from continentally derived organic matter. All have sandstone reservoirs. Most have shale seals, but one, Sarir, has an evaporite seal. Many are faulted anticlines. Some of the anticlines formed in a compressional tectonic setting, whereas others formed in a tensional tectonic setting.

Beaumont, E.A.; Foster, N.H.

1990-01-01T23:59:59.000Z

45

Modular cryostat for ion trapping with surface-electrode ion traps  

E-Print Network (OSTI)

We present a simple cryostat purpose built for use with surface-electrode ion traps, designed around an affordable, large cooling power commercial pulse tube refrigerator. A modular vacuum enclosure with a single vacuum space facilitates interior access, and enables rapid turnaround and flexiblity for future modifications. Long rectangular windows provide nearly 360 degrees of optical access in the plane of the ion trap, while a circular bottom window near the trap enables NA 0.4 light collection without the need for in-vacuum optics. We evaluate the system's mechanical and thermal characteristics, and we quantify ion trapping performance by trapping 40Ca+, finding small stray electric fields, long ion lifetimes, and low ion heating rates.

Vittorini, Grahame; Brown, Kenneth R; Harter, Alexa W; Doret, S Charles

2013-01-01T23:59:59.000Z

46

Modular cryostat for ion trapping with surface-electrode ion traps  

Science Journals Connector (OSTI)

We present a simple cryostat purpose built for use with surface-electrode ion traps designed around an affordable large cooling power commercial pulse tube refrigerator. A modular vacuum enclosure with a single vacuum space facilitates interior access and enables rapid turnaround and flexibility for future modifications. Long rectangular windows provide nearly 360° of optical access in the plane of the ion trap while a circular bottom window near the trap enables NA 0.4 light collection without the need for in-vacuum optics. We evaluate the system's mechanical and thermal characteristics and we quantify ion trapping performance by trapping 40Ca+ finding small stray electric fields long ion lifetimes and low ion heating rates.

Grahame Vittorini; Kenneth Wright; Kenneth R. Brown; Alexa W. Harter; S. Charles Doret

2013-01-01T23:59:59.000Z

47

Modular cryostat for ion trapping with surface-electrode ion traps  

E-Print Network (OSTI)

We present a simple cryostat purpose built for use with surface-electrode ion traps, designed around an affordable, large cooling power commercial pulse tube refrigerator. A modular vacuum enclosure with a single vacuum space facilitates interior access, and enables rapid turnaround and flexiblity for future modifications. Long rectangular windows provide nearly 360 degrees of optical access in the plane of the ion trap, while a circular bottom window near the trap enables NA 0.4 light collection without the need for in-vacuum optics. We evaluate the system's mechanical and thermal characteristics, and we quantify ion trapping performance by trapping 40Ca+, finding small stray electric fields, long ion lifetimes, and low ion heating rates.

Grahame Vittorini; Kenneth Wright; Kenneth R. Brown; Alexa W. Harter; S. Charles Doret

2013-02-20T23:59:59.000Z

48

Neutron-Mirror-Neutron Oscillations in a Trap  

E-Print Network (OSTI)

We calculate the rate of neutron-mirror-neutron oscillations for ultracold neutrons trapped in a storage vessel. Recent experimental bounds on the oscillation time are discussed.

B. Kerbikov; O. Lychkovskiy

2008-04-03T23:59:59.000Z

49

Neutron–mirror-neutron oscillations in a trap  

Science Journals Connector (OSTI)

We calculate the rate of neutron–mirror-neutron oscillations for ultracold neutrons trapped in a storage vessel. Recent experimental bounds on the oscillation time are discussed.

B. Kerbikov and O. Lychkovskiy

2008-06-27T23:59:59.000Z

50

Chemical dynamics in the gas phase: Time-dependent quantum mechanics of chemical reactions  

SciTech Connect

A major goal of this research is to obtain an understanding of the molecular reaction dynamics of three and four atom chemical reactions using numerically accurate quantum dynamics. This work involves: (i) the development and/or improvement of accurate quantum mechanical methods for the calculation and analysis of the properties of chemical reactions (e.g., rate constants and product distributions), and (ii) the determination of accurate dynamical results for selected chemical systems, which allow one to compare directly with experiment, determine the reliability of the underlying potential energy surfaces, and test the validity of approximate theories. This research emphasizes the use of recently developed time-dependent quantum mechanical methods, i.e. wave packet methods.

Gray, S.K. [Argonne National Laboratory, IL (United States)

1993-12-01T23:59:59.000Z

51

Heating of trapped ultracold atoms by collapse dynamics  

E-Print Network (OSTI)

{The Continuous Spontaneous Localization (CSL) theory alters the Schr\\"odinger equation. It describes wave function collapse as a dynamical process instead of an ill-defined postulate, thereby providing macroscopic uniqueness and solving the so-called measurement problem of standard quantum theory. CSL contains a parameter $\\lambda$ giving the collapse rate of an isolated nucleon in a superposition of two spatially separated states and, more generally, characterizing the collapse time for any physical situation. CSL is experimentally testable, since it predicts some behavior different from that predicted by standard quantum theory. One example is the narrowing of wave functions, which results in energy imparted to particles. Here we consider energy given to trapped ultra-cold atoms. Since these are the coldest samples under experimental investigation, it is worth inquiring how they are affected by the CSL heating mechanism. We examine the CSL heating of a BEC in contact with its thermal cloud. Of course, other mechanisms also provide heat and also particle loss. From varied data on optically trapped cesium BEC's, we present an energy audit for known heating and loss mechanisms. The result provides an upper limit on CSL heating and thereby an upper limit on the parameter $\\lambda$. We obtain $\\lambda\\lesssim 1(\\pm1)\\times 10^{-7}$sec$^{-1}$.}

Franck Laloë; William J. Mullin; Philip Pearle

2014-11-12T23:59:59.000Z

52

Photoluminescence Blinking Dynamics of Colloidal Quantum Dots in the Presence of Controlled External Electron Traps  

SciTech Connect

The effect of the external charge trap on the photoluminescence blinking dynamics of individual colloidal quantum dots is investigated with a series of colloidal quantum dot-bridge-fullerene dimers with varying bridge lengths, where the fullerene moiety acts as a well-defined, well-positioned external charge trap. It is found that charge transfer followed by charge recombination is an important mechanism in determining the blinking behavior of quantum dots when the external trap is properly coupled with the excited state of the quantum dot, leading to a quasi-continuous distribution of 'on' states and an early fall-off from a power-law distribution for both 'on' and 'off' times associated with quantum dot photoluminescence blinking.

Cotlet, M.; Xu, Z.

2012-01-23T23:59:59.000Z

53

Electron Trapping by Molecular Vibration  

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

Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the...

54

Evaluating Steam Trap Performance  

E-Print Network (OSTI)

~LmT " TRIf' 1 TRIf' 2 Figure 2 It has become common practice for engineers to oversize steam traps and place more emphasis on first cost than on maintenance cost and operating 766 3 4 ESL-IE-86-06-126 Proceedings from the Eighth Annual Industrial...EVALUATING STEAM TRAP PERFORMANCE Noel Y Fuller, P.E. Holston Defense Corporation Kingsport, Tennessee ABSTRACT Laboratory tests were conducted on several types of steam traps at Holston Defense Corporation in Kingsport, Tennessee. Data...

Fuller, N. Y.

55

Trapping of Gun-Injected Plasma by a Tokamak  

Science Journals Connector (OSTI)

It is shown that a plasma produced by a Marshall gun can be injected into and trapped by a tokamak plasma. Gun injection raises the line-averaged density and peaks the density profile. Trapping of the gun-injected plasma is explainable in terms of a depolarization current mechanism.

A. W. Leonard; R. N. Dexter; J. C. Sprott

1986-07-21T23:59:59.000Z

56

TRAPping Modelica with Python  

Science Journals Connector (OSTI)

This short paper introduces TRAP, a small but powerful compiler development system based on the object-oriented, dynamic language Python. Employing a very high level language as a compiler tool’s base language re...

Thilo Ernst

1999-01-01T23:59:59.000Z

57

Trapping and Probing Antihydrogen  

SciTech Connect

Precision spectroscopy of antihydrogen is a promising path to sensitive tests of CPT symmetry. The most direct route to achieve this goal is to create and probe antihydrogen in a magnetic minimum trap. Antihydrogen has been synthesized and trapped for 1000s at CERN by the ALPHA Collaboration. Some of the challenges associated with achieving these milestones will be discussed, including mixing cryogenic positron and antiproton plasmas to synthesize antihydrogen with kinetic energy less than the trap potential of .5K. Recent experiments in which hyperfine transitions were resonantly induced with microwaves will be presented. The opportunity for gravitational measurements in traps based on detailed studies of antihydrogen dynamics will be described. The talk will conclude with a discussion future antihydrogen research that will use a new experimental apparatus, ALPHA-I.

Wurtele, Jonathan [UC Berkeley and LBNL

2013-03-27T23:59:59.000Z

58

Disproportionation Channel of Self-Reaction of Hydroxyl Radical, OH + OH ? H2O + O, Studied by Time-Resolved Oxygen Atom Trapping  

Science Journals Connector (OSTI)

The original curve taken with the time resolution of 3 usec and 2 usec/point was smoothed by a 50 points-adjacent averaging. ...

Manuvesh Sangwan; Lev N. Krasnoperov

2012-11-05T23:59:59.000Z

59

System and method for trapping and measuring a charged particle in a liquid  

DOE Patents (OSTI)

A system and method for trapping a charged particle is disclosed. A time-varying periodic multipole electric potential is generated in a trapping volume. A charged particle under the influence of the multipole electric field is confined to the trapping volume. A three electrode configuration giving rise to a 3D Paul trap and a four planar electrode configuration giving rise to a 2D Paul trap are disclosed.

Reed, Mark A; Krstic, Predrag S; Guan, Weihua; Zhao, Xiongce

2013-07-23T23:59:59.000Z

60

Structural traps 5  

SciTech Connect

This book contains studies of oil and gas fields that are mainly structural in nature. Stratigraphy controls the extend of the reservoir in the traps of several fields, but overall, the main trapping features within the group of fields in this volume are structural. Fields covered in this volume include: Endicott Field, Point Arguello Field, West Puerto Chiquito Field, Dukhan Field, Sendji Field, Ruston Field, Raudhatain Field, Hassi Messaoud Field, Snapper Field, Tirrawarra Field, and Sacha Field.

Foster, N.H.; Beaumont, E.A.

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Steam Trap Application  

E-Print Network (OSTI)

characteristics. 2. Understand advantages and limitations of various checking methods. 3. Use more than one checking method. 4. Understand flash condensate. 5. Condensate makes more noise than steam. 6. Trouble shoot the system. 7. Review trap... or failed steam and condensate flow~' H closed to be undetected -Not always insensitive to back ground or ambient noise -Noise in electrical system if volume too high -Head set quality important -Location of probe on trap, contact force, pressure drop...

Murphy, J. J.

1982-01-01T23:59:59.000Z

62

Structural traps 2  

SciTech Connect

This book contains studies of fields that exist because of the presence of tectonic faulting. Tectonic faulting occurs because of the release of crustal stresses. Nontectonic faulting is due to other factors, such as salt solution and collapse or detachment from sedimentary loading and slumping. The traps responsible for the fields in this volume are related either directly or indirectly to a fault block. The traps of Amposta, Cano Limon, Ninian, Renqiu, and Sarir are directly related to a fault block. Brent and Magnus fields are the result of traps formed by an unconformity truncation and a tilted fault block. Mobeetie field is the result of a trap indirectly related to a fault block. The anticline associated with the trap formed by differential compaction over a basement fault block. Red Oak field comprises traps both in a fault block and in an overlying anticline formed by differential compaction over the same fault block. With the exception of Cano Limon, all the fault blocks associated with these fields formed mainly under tensional stresses. The fault block associated with Cano Limon field formed by shearing in a strike-slip environment. Another aspect described in each field study is the history of its exploration and development.

Beaumont, E.A.; Foster, N.H.

1990-01-01T23:59:59.000Z

63

Effect of treatment time on characterization and properties of nanocrystalline surface layer in copper induced by surface mechanical attrition treatment  

Science Journals Connector (OSTI)

Nanocrystalline surface layers were synthesized on pure copper by means of surface mechanical attrition treatment (SMAT) at various treatment times. The microstructural features of the surface layers produced by ...

Farzad Kargar; M. Laleh; T. Shahrabi; A. Sabour Rouhaghdam

2014-08-01T23:59:59.000Z

64

Plasma production by the trapping of energetic atoms  

Science Journals Connector (OSTI)

The production of a hot plasma by the injection of streams of energetic atoms into a confining magnetic field is discussed. The experiments described are directed towards injection of 20-keV hydrogen or deuterium atoms into a magnetic mirror field. The results of some numerical calculations of the plasma growth to a steady-state in a constant magnetic field are presented, including the calculation of the spatial distribution of the trapped ions. In these calculations, the primary trapping mechanism is the ionization of beam atoms by trapped ions and electrons. Parametric values are assigned to approximate the experimentally attainable conditions. The indicated equilibrium densities are in the range of 1014/cm3, at ? ? 1%, with typical growth times of a few seconds, if the final density is determined by ion-ion scattering into the mirror loss cone.The practical achievement of a hot plasma by this injection method depends upon maximizing the trapping rate, and minimizing the particle loss due to charge-exchange scattering. Severe requirements are therefore placed on the atomic beam intensity and the gas density in the confinement region. Some of the requirements on the build-up conditions imposed by plasma stability considerations are also discussed.Progress toward meeting the technological requirements is described. A highly collimated beam of hydrogen atoms in excess of 5 × 1017 atoms/sec at 20-keV energy has been produced. The cross-sectional area of the beam is 20 cm2 at a distance of 360 cm from the source; the half-angle divergence is less than 10 milliradians. Vacuum techniques have been developed to achieve base pressures in the 10?10 mm Hg range without extensive bakeout procedure. At the same time pumping speeds exceeding 105l/sec for hydrogen are available.A method of trapping the energetic atoms by means of a transient “cold” plasma is also discussed. This procedure greatly increases the initial plasma growth rate. The plasma density attainable depends upon the beam intensity, vacuum, and cold plasma density, the latter two being time-dependent. The generation of a suitable cold plasma is described.

C.C. Damm; A.H. Futch; F. Gordon; A.L. Hunt; E.C. Popp; R.F. Post; J.F. Steinhaus

1961-01-01T23:59:59.000Z

65

Time Scales and Mechanisms of Relaxation in the Energy Landscape of Polymer Glass under Deformation: Direct Atomistic Modeling  

Science Journals Connector (OSTI)

Molecular-dynamics simulation is used to explore the influence of thermal and mechanical history of typical glassy polymers on their deformation. Polymer stress-strain and energy-strain developments have been followed for different deformation velocities, also in closed extension-recompression loops. The latter simulate for the first time the experimentally observed mechanical rejuvenation and overaging of polymers, and energy partitioning reveals essential differences between mechanical and thermal rejuvenation. All results can be qualitatively interpreted by considering the ratios of the relevant time scales: for cooling down, for deformation, and for segmental relaxation.

Alexey V. Lyulin and M. A. J. Michels

2007-08-24T23:59:59.000Z

66

Antihydrogen Trapped in the ALPHA Experiment  

ScienceCinema (OSTI)

In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i]  Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome.   The unique design features of the ALPHA apparatus will be explained.[ii]  These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise the perturbations to trapped charged particles which may cause particle loss and heating[iv].   The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried.   The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures',                                   G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii]  'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106, 025002 (2011) Organizer: Ferdinand Hahn PH/DT Detector Seminar webpage  

None

2011-04-25T23:59:59.000Z

67

Coherence in Microchip Traps  

Science Journals Connector (OSTI)

We report the coherent manipulation of internal states of neutral atoms in a magnetic microchip trap. Coherence lifetimes exceeding 1 s are observed with atoms at distances of 5–130????m from the microchip surface. The coherence lifetime in the chip trap is independent of atom-surface distance within our measurement accuracy and agrees well with the results of similar measurements in macroscopic magnetic traps. Because of the absence of surface-induced decoherence, a miniaturized atomic clock with a relative stability in the 10-13 range can be realized. For applications in quantum information processing, we propose to use microwave near fields in the proximity of chip wires to create potentials that depend on the internal state of the atoms.

Philipp Treutlein; Peter Hommelhoff; Tilo Steinmetz; Theodor W. Hänsch; Jakob Reichel

2004-05-21T23:59:59.000Z

68

Asymmetric ion trap  

DOE Patents (OSTI)

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode is disclosed. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity. 4 figs.

Barlow, S.E.; Alexander, M.L.; Follansbee, J.C.

1997-12-02T23:59:59.000Z

69

Asymmetric ion trap  

DOE Patents (OSTI)

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

Barlow, Stephan E. (Richland, WA); Alexander, Michael L. (Richland, WA); Follansbee, James C. (Pasco, WA)

1997-01-01T23:59:59.000Z

70

CONTINUOUS FLOW "RAIL-AND-TRAP" MICROFLUIDIC PROCESSORS FOR AUTONOMOUS  

E-Print Network (OSTI)

CONTINUOUS FLOW "RAIL-AND-TRAP" MICROFLUIDIC PROCESSORS FOR AUTONOMOUS BEAD-BASED MIXING laborious and time intensive fluidic mixing procedures. Although microfluidic platforms offer significant, here we present a microfluidic "rail-and-trap" processor that functions autonomously under continuous

Lin, Liwei

71

Venus Fly Trap Experiment  

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

Venus Fly Trap Experiment Venus Fly Trap Experiment Name: Jeremy Bailey Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A Question: My name is Jeremy Bailey, and I am a student of Dorseyville Middle School. I have been working on a science project about Venus' Fly Traps. A recent addition to the project involved designing an experiment about something I found interesting about them. However, I don't know where to get them or how to grow them in the moderate climate of Pittsburgh. Also, I don't know how a successful experiment could be designed. Replies: Jeremy, I believe Venus Fly traps can be found 'in the wild' in the coastal floodplain of the Carolinas. As far as where to buy them, look in the phonebook yellow pages under plants or houseplants and do some calling. I live in eastern Pennsylvania, and over here they even sell them in hardware stores like Hechinger's and Home Depot (in their garden departments). I don't think you will have luck trying to grow them outside, our winters here are a bit too harsh for them. From what I recall they require substantial moisture and more moderate climes. You might try looking for houseplant books at your local library for more detailed information.

72

Nuclear Physics with trapped  

E-Print Network (OSTI)

Nuclear Physics with trapped atoms and ions #12;2/2/2013Dan Melconian #12;2/2/2013Dan Melconian Outline · Scope and applications of nuclear physics precision frontier compliments LHC properties and aquifers in the Sahara #12;2/2/2013Dan Melconian What is Nuclear Physics? · Began with the study

Boas, Harold P.

73

February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms by light scattering  

E-Print Network (OSTI)

February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms of optically trapped atoms that is due to light scattering from the trap laser. We observe relaxation times greater than 2 s for ground-state hyperfine-levelpopulations of 85 Rb atoms trapped in an optical dipole

Heinzen, Daniel J.

74

Cavity cooling of an optically trapped nanoparticle  

Science Journals Connector (OSTI)

We study the cooling of a dielectric nanoscale particle trapped in an optical cavity. We derive the frictional force for motion in the cavity field and show that the cooling rate is proportional to the square of oscillation amplitude and frequency. Both the radial and axial components of the center-of-mass motion of the trapped particle, which are coupled by the cavity field, are cooled. This motion is analogous to two coupled but damped pendulums. Our simulations show that the nanosphere can be cooled to e-1 of its initial momentum over time scales of hundredths of milliseconds.

P. F. Barker and M. N. Shneider

2010-02-23T23:59:59.000Z

75

Master equation approach to protein folding and kinetic traps  

E-Print Network (OSTI)

The master equation for 12-monomer lattice heteropolymers is solved numerically and the time evolution of the occupancy of the native state is determined. At low temperatures, the median folding time follows the Arrhenius law and is governed by the longest relaxation time. For good folders, significant kinetic traps appear in the folding funnel whereas for bad folders, the traps also occur in non-native energy valleys.

Marek Cieplak; Malte Henkel; Jan Karbowski; Jayanth R. Banavar

1998-04-21T23:59:59.000Z

76

Wednesday, January 30, 2013 Infrared Trapping the "Greenhouse Effect"  

E-Print Network (OSTI)

Wednesday, January 30, 2013 Infrared Trapping ­ the "Greenhouse Effect" Goals ­ to look is the same as a 1.8 degree F change. #12;Last time - Greenhouse effect demo Selective absorption. Greenhouse

Toohey, Darin W.

77

The metabolic and mechanical costs of step time asymmetry in walking  

Science Journals Connector (OSTI)

...stride cycle from the right foot forces. For the asymmetric...phase-shifted the left foot GRF by the percentage...calculated individual limb power after Donelan et al...metabolic and mechanical power. We also tested whether...performed this test for each foot when that foot was the...

2013-01-01T23:59:59.000Z

78

The Elimination of Steam Traps  

E-Print Network (OSTI)

claims and misinformation gener ated by over thirty-six steam trap manufacturers in the United States alone. A PARTIAL LIST OF STEAM TRAP MANUFACTURERS AAF GESTRA ANDERSON HIROSS ARMSTRONG HOFFMAN BARNES &JONES HONEYWELL BRAUKMANN BESTOBELL... removal had been devised and these same methods, with minor variations, are employed today. The inverted bucket trap was in vented in 1910 by Otto Arner, a friend of Adam Armstrong. Armstrong began his business career by making bicycle spokes...

Dickman, F.

79

Inspect and Repair Steam Traps  

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

This tip sheet on inspecting and repairing steam traps provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

80

Trapping triply ionized thorium isotopes.  

E-Print Network (OSTI)

??Cold trapped ions have many applications in quantum information science and precision metrology. In this thesis, we present progress toward two objectives involving ions confined… (more)

Churchill, Layne Russell

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Electron Trapping by Molecular Vibration  

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

Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally...

82

Exciton self-trapping in bulk polyethylene  

E-Print Network (OSTI)

We studied theoretically the behavior of an injected electron-hole pair in crystalline polyethylene. Time-dependent adiabatic evolution by ab-initio molecular dynamics simulations show that the pair will become self-trapped in the perfect crystal, with a trapping energy of about 0.38 eV, with formation of a pair of trans-gauche conformational defects, three C$_2$H$_4$ units apart on the same chain. The electron is confined in the inter-chain pocket created by a local, 120$^\\circ$ rotation of the chain between the two defects, while the hole resides on the chain and is much less bound. Despite the large energy stored in the trapped excitation, there does not appear to be a direct non-radiative channel for electron-hole recombination. This suggests that intrinsic self-trapping of electron-hole pairs inside the ideal quasi-crystalline fraction of PE might not be directly relevant for electrical damage in high-voltage cables.

D. Ceresoli; M. C. Righi; E. Tosatti; S. Scandolo; G. Santoro; S. Serra

2005-07-13T23:59:59.000Z

83

Time and location differentiated NOX control in competitive electricity markets using cap-and-trade mechanisms  

E-Print Network (OSTI)

Due to variations in weather and atmospheric chemistry, the timing and location of nitrogen oxide (NOX) reductions determine their effectiveness in reducing ground-level ozone, which adversely impacts human health. Electric ...

Martin, Katherine C.

2007-01-01T23:59:59.000Z

84

Cryogenic silicon surface ion trap  

E-Print Network (OSTI)

Trapped ions are pre-eminent candidates for building quantum information processors and quantum simulators. They have been used to demonstrate quantum gates and algorithms, quantum error correction, and basic quantum simulations. However, to realise the full potential of such systems and make scalable trapped-ion quantum computing a reality, there exist a number of practical problems which must be solved. These include tackling the observed high ion-heating rates and creating scalable trap structures which can be simply and reliably produced. Here, we report on cryogenically operated silicon ion traps which can be rapidly and easily fabricated using standard semiconductor technologies. Single $^{40}$Ca$^+$ ions have been trapped and used to characterize the trap operation. Long ion lifetimes were observed with the traps exhibiting heating rates as low as $\\dot{\\bar{n}}=$ 0.33 phonons/s at an ion-electrode distance of 230 $\\mu$m. These results open many new avenues to arrays of micro-fabricated ion traps.

Michael Niedermayr; Kirill Lakhmanskiy; Muir Kumph; Stefan Partel; Johannes Edlinger; Michael Brownnutt; Rainer Blatt

2014-03-20T23:59:59.000Z

85

Meteoritical and dynamical constraints on the growth mechanisms and formation times of asteroids and Jupiter  

E-Print Network (OSTI)

Peak temperatures inside meteorite parent bodies are closely linked to accretion times. Most iron meteorites come from bodies that accreted 3-5 Myr after CAIs formed. This precludes formation of Jupiter via a gravitational instability <1 Myr after the solar nebula formed, and strongly favors core accretion. Shocks formed by gravitational instabilities in the disk, proto-Jupiter, or by planetary embryos may have produced some chondrules. The minimum lifetime for the solar nebula of 3-5 Myr inferred from CAI and chondrule ages may exceed the median 3 Myr lifetime for protoplanetary disks, but is well within the total 1-10 Myr range. Shorter formation times for extrasolar planets may help to explain why their orbits are unlike those of solar giant planets.

Edward R. D. Scott

2006-07-13T23:59:59.000Z

86

Revealing cyclic hardening mechanism of a TRIP steel by real-time in situ neutron diffraction  

SciTech Connect

Real-time in situ neutron diffraction was performed on a transformation-induced plasticity (TRIP) steel under cyclic loading at room temperature. By Rietveld refinement and single peak analysis, the volume fraction and average stress estimates as well as dislocation density of individual phases (austenite and martensite phase) were derived. The results reveal that the volume fraction of martensite phase, instead of individual phase strengthening, should be accounted for the remarkable secondary cyclic hardening.

Yu, Dunji [ORNL; An, Ke [ORNL; Chen, Yan [ORNL; Chen, Xu [Tianjin UNiversity, China

2014-01-01T23:59:59.000Z

87

Effects of dynamical collapse theory on trapped ultra-cold atoms  

E-Print Network (OSTI)

The Continuous Spontaneous Localization (CSL) theory alters the Schr\\"odinger equation. It describes wave function collapse as a dynamical process instead of an ill-defined postulate, thereby providing macroscopic uniqueness and solving the so-called measurement problem of standard quantum theory. CSL contains a parameter $\\lambda$ giving the collapse rate of an isolated nucleon in a superposition of two spatially separated states and, more generally, characterizing the collapse time for any physical situation. CSL is experimentally testable, since it predicts some behavior different from that predicted by standard quantum theory. One example is the narrowing of wave functions, which results in energy imparted to particles. Here we consider energy given to trapped ultra-cold atoms. Since these are the coldest samples under experimental investigation, it is worth inquiring how they are affected by the CSL heating mechanism. We examine the CSL heating of a BEC in contact with its thermal cloud. Of course, other mechanisms also provide heat and also particle loss. From varied data on optically trapped cesium BEC's, we present an energy audit for known heating and loss mechanisms. The result provides an upper limit on CSL heating and thereby an upper limit on the parameter $\\lambda$. We obtain $\\lambda\\lesssim 1(\\pm1)\\times 10^{-7}$sec$^{-1}$.

Franck Laloë; William J. Mullin; Philip Pearle

2014-09-18T23:59:59.000Z

88

Precursory signatures of protein folding/unfolding: From time series correlation analysis to atomistic mechanisms  

SciTech Connect

Folded conformations of proteins in thermodynamically stable states have long lifetimes. Before it folds into a stable conformation, or after unfolding from a stable conformation, the protein will generally stray from one random conformation to another leading thus to rapid fluctuations. Brief structural changes therefore occur before folding and unfolding events. These short-lived movements are easily overlooked in studies of folding/unfolding for they represent momentary excursions of the protein to explore conformations in the neighborhood of the stable conformation. The present study looks for precursory signatures of protein folding/unfolding within these rapid fluctuations through a combination of three techniques: (1) ultrafast shape recognition, (2) time series segmentation, and (3) time series correlation analysis. The first procedure measures the differences between statistical distance distributions of atoms in different conformations by calculating shape similarity indices from molecular dynamics simulation trajectories. The second procedure is used to discover the times at which the protein makes transitions from one conformation to another. Finally, we employ the third technique to exploit spatial fingerprints of the stable conformations; this procedure is to map out the sequences of changes preceding the actual folding and unfolding events, since strongly correlated atoms in different conformations are different due to bond and steric constraints. The aforementioned high-frequency fluctuations are therefore characterized by distinct correlational and structural changes that are associated with rate-limiting precursors that translate into brief segments. Guided by these technical procedures, we choose a model system, a fragment of the protein transthyretin, for identifying in this system not only the precursory signatures of transitions associated with ? helix and ? hairpin, but also the important role played by weaker correlations in such protein folding dynamics.

Hsu, P. J.; Lai, S. K., E-mail: sklai@coll.phy.ncu.edu.tw [Complex Liquids Laboratory, Department of Physics, National Central University, Chungli 320 Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Cheong, S. A. [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

2014-05-28T23:59:59.000Z

89

Trapping and cooling He(2{sup 3}S) metastable atoms  

SciTech Connect

A magneto-optical trap for He(2{sup 3}S) metastable atoms has been constructed, utilizing superconducting magnetic gradient coils and a Ti:Sapphire ring laser for pumping the helium 2{sup 3}S-2{sup 3}P transition. The He(2{sup 3}S) atoms are produced by a weak rf discharge in helium gas at a temperature of 1.4K. The discharge products flow through a small orifice into the trap cell, where a fraction of the He(2{sup 3}S) atoms are trapped and ground state helium atoms are rapidly cryopumped by zeolite pellets that cover most of the cell bottom. Preliminary experiments suggest that {approximately}10{sup 6} atoms are trapped in a small volume at {approximately}1 mK, with a trap lifetime of 10-100 msec limited by resonantly-enhanced He(2{sup 3}S)-He(2{sup 3}P) Penning reactions. Ultimately, it is estimated that a substantial number of atoms can be held at ultra-low temperature in near-perfect vacuum, in a dc magnetic trap. Measurements of decay times of the trapped atoms should yield rate coefficients in the quantum regime for He(2{sup 3}S)-He(2{sup 3}P) and He(2{sup 3}S)-He(2{sup 3}S) Penning reactions, and perhaps the He(2{sup 3}S) radiative lifetime.

Zhao, X.; Soletsky, P.A.; Bryan, W.H.; Ling, X. [and others

1993-05-01T23:59:59.000Z

90

A non-discrete method for computation of residence time in fluid mechanics simulations  

Science Journals Connector (OSTI)

Cardiovascular simulations provide a promising means to predict risk of thrombosis in grafts devices and surgical anatomies in adult and pediatric patients. Although the pathways for platelet activation and clot formation are not yet fully understood recent findings suggest that thrombosis risk is increased in regions of flow recirculation and high residence time (RT). Current approaches for calculating RT are typically based on releasing a finite number of Lagrangian particles into the flow field and calculating RT by tracking their positions. However special care must be taken to achieve temporal and spatial convergence often requiring repeated simulations. In this work we introduce a non-discrete method in which RT is calculated in an Eulerian framework using the advection-diffusion equation. We first present the formulation for calculating residence time in a given region of interest using two alternate definitions. The physical significance and sensitivity of the two measures of RT are discussed and their mathematical relation is established. An extension to a point-wise value is also presented. The methods presented here are then applied in a 2D cavity and two representative clinical scenarios involving shunt placement for single ventricle heart defects and Kawasaki disease. In the second case study we explored the relationship between RT and wall shear stress a parameter of particular importance in cardiovascular disease.

Alison L. Marsden

2013-01-01T23:59:59.000Z

91

Effect of milling time and CNT concentration on hardness of CNT/Al{sub 2024} composites produced by mechanical alloying  

SciTech Connect

Carbon nanotube/2024 aluminum alloy (CNT/Al{sub 2024}) composites were fabricated with a combination of mechanical alloying (MA) and powder metallurgy routes. Composites were microstructurally and mechanically evaluated at sintering condition. A homogeneous dispersion of CNTs in the Al matrix was observed by a field emission scanning electron microscopy. High-resolution transmission electron microscopy confirmed not only the presence of well dispersed CNTs but also needle-like shape aluminum carbide (Al{sub 4}C{sub 3}) crystals in the Al matrix. The formation of Al{sub 4}C{sub 3} was suggested as the interaction between the outer shells of CNTs and the Al matrix during MA process in which crystallization took place after the sintering process. The mechanical behavior of composites was evaluated by Vickers microhardness measurements indicating a significant improvement in hardness as function of the CNT content. This improvement was associated to a homogeneous dispersion of CNTs and the presence of Al{sub 4}C{sub 3} in the aluminum alloy matrix. - Highlights: Black-Right-Pointing-Pointer The 2024 aluminum alloy was reinforced by CNTs by mechanical alloying process. Black-Right-Pointing-Pointer Composites were microstructural and mechanically evaluated after sintering condition. Black-Right-Pointing-Pointer The greater the CNT concentration, the greater the hardness of the composites. Black-Right-Pointing-Pointer Higher hardness in composites is achieved at 20 h of milling. Black-Right-Pointing-Pointer The formation of Al{sub 4}C{sub 3} does not present a direct relationship with the milling time.

Perez-Bustamante, R. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico)] [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico); Perez-Bustamante, F. [Universidad Autonoma de Chihuahua (UACH), Facultad de Ingenieria, Circuito No. 1 Nuevo Campus Universitario, C.P. 31125, Chihuahua, Chih. (Mexico)] [Universidad Autonoma de Chihuahua (UACH), Facultad de Ingenieria, Circuito No. 1 Nuevo Campus Universitario, C.P. 31125, Chihuahua, Chih. (Mexico); Estrada-Guel, I. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico)] [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico); Licea-Jimenez, L. [Centro de Investigacion en Materiales Avanzados S.C. (CIMAV), Unidad Mty, Autopista Monterrey-Aeropuerto Km 10, A. P. 43, C.P. 66600, Apodaca, N.L. (Mexico)] [Centro de Investigacion en Materiales Avanzados S.C. (CIMAV), Unidad Mty, Autopista Monterrey-Aeropuerto Km 10, A. P. 43, C.P. 66600, Apodaca, N.L. (Mexico); Miki-Yoshida, M. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico)] [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico); Martinez-Sanchez, R., E-mail: roberto.martiez@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No.120, C.P. 31109, Chihuahua, Chih. (Mexico)

2013-01-15T23:59:59.000Z

92

Properties of few-body systems in relativistic quantum mechanics and constraints from transformations under Poincaré space-time translations  

E-Print Network (OSTI)

Different approaches have been applied to the calculation of form factors of various hadronic systems within relativistic quantum mechanics. In a one-body current approximation, they can lead to results evidencing large discrepancies. Looking for an explanation of this spreading, it is shown that, for the largest part, these discrepancies can be related to a violation of Poincar\\'e space-time translation invariance. Beyond energy-momentum conservation, which is generally assumed, fulfilling this symmetry implies specific relations that are generally ignored. Their relevance within the present context is discussed in detail both to explain the differences between predictions and to remove them.

B. Desplanques

2006-11-17T23:59:59.000Z

93

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

E-Print Network (OSTI)

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before:the probability of UCN losses from the trap was only 1% of that for neutron beta decay. The neutron lifetime obtained,878.5+/-0.7stat+/-0.3sys s, is the most accurate experimental measurement to date.

A. P. Serebrov; V. E. Varlamov; A. G. Kharitonov; A. K. Fomin; Yu. N. Pokotilovski; P. Geltenbort; I. A. Krasnoschekova; M. S. Lasakov; R. R. Taldaev; A. V. Vassiljev; O. M. Zherebtsov

2007-02-06T23:59:59.000Z

94

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

SciTech Connect

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before: the probability of UCN losses from the trap was only 1% of that for neutron {beta} decay. The neutron lifetime obtained, 878.5{+-}0.7{sub stat}{+-}0.3{sub sys} s, is the most accurate experimental measurement to date.

Serebrov, A. P.; Varlamov, V. E.; Kharitonov, A. G.; Fomin, A. K.; Krasnoschekova, I. A.; Lasakov, M. S.; Taldaev, R. R.; Vassiljev, A. V.; Zherebtsov, O. M. [Petersburg Nuclear Physics Institute, Russian Academy of Sciences, RU-188300 Gatchina, Leningrad District (Russian Federation); Pokotilovski, Yu. N. [Joint Institute for Nuclear Research, RU-141980 Dubna, Moscow Region (Russian Federation); Geltenbort, P. [Institut Max von Laue Paul Langevin, Boite Postal 156, F-38042 Grenoble Cedex 9 (France)

2008-09-15T23:59:59.000Z

95

A variational calculation of the trapping rate in thermal barriers  

Science Journals Connector (OSTI)

A variational calculation of the trapping rate and trapped-ion density in thermal barriers is presented. The effects of diffusion in energy as well as pitch-angle scattering are retained. The variational formulation uses the actual trapped/passing boundary in velocity space. The boundary condition is that the trapped-ion distribution function match the passing-ion distribution function, which is taken to be a Maxwellian, on the boundary. The results compare well with the two-dimensional Fokker-Planck code calculations by Futch and LoDestro. The CPU time for a variational calculation is less than 0.1 s using the CRAY-I computer, while a typical Fokker-Planck code calculation takes 10–20 min.

X.Z. Li; G.A. Emmert

1984-01-01T23:59:59.000Z

96

Mini ion trap mass spectrometer  

DOE Patents (OSTI)

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Dietrich, D.D.; Keville, R.F.

1995-09-19T23:59:59.000Z

97

Mini ion trap mass spectrometer  

DOE Patents (OSTI)

An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

1995-01-01T23:59:59.000Z

98

Managing the Steam Trap Population  

E-Print Network (OSTI)

hundred steam traps installed only 58 were working effectively -- 42% needed attention! These programs had associated cost benefits of at least 100% return on investment, a maximum six month breakeven on cash flow, and an energy cost reduction amounting...

Atlas, R. D.

1983-01-01T23:59:59.000Z

99

Novel Dipole Trapped Spheromak Configuration  

Science Journals Connector (OSTI)

We report the observation and characterization of a spheromak formed in the Swarthmore Spheromak Experiment (SSX) and trapped in a simple dipole magnetic field. The spheromak is studied in the prolate (tilt unsta...

M. R. Brown; C. D. Cothran; J. Fung; M. J. Schaffer; E. Belova

2007-06-01T23:59:59.000Z

100

Rainbow trapping of guided waves  

E-Print Network (OSTI)

Rainbow trapping of guided waves Javier Polanco and Rosa M.the propagation of a wave packet that is a superpositionof three s-polarized guided waves with different frequencies

Polanco, Javier; Fitzgerald, Rosa M; Leskova, Tamara A; Maradudin, Alexei A

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Quantum Engineering with Trapped Ions  

Science Journals Connector (OSTI)

We describe how to manipulate, and characterize the motional state of a trapped ion. We also give a method to measure an arbitrary motional observable in a single shot.

J. F. Poyatos; S. A. Gardiner; R. Walser…

1997-01-01T23:59:59.000Z

102

Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons  

E-Print Network (OSTI)

The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons (UCN) in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing scintillation light that is detected using photomultiplier tubes. Statistical limitations of the previous apparatus will be alleviated by significant increases in field strength and trap volume resulting in twenty times more trapped neutrons.

C. M. O'Shaughnessy; R. Golub; K. W. Schelhammer; C. M. Swank; P. -N. Seo; P. R. Huffman; S. N. Dzhosyuk; C. E. H. Mattoni; L. Yang; J. M. Doyle; K. J. Coakley; A. K. Thompson; H. P. Mumm; S. K. Lamoreaux; G. Yang

2009-03-31T23:59:59.000Z

103

Integrated photonic structures for light trapping in thin-film Si solar cells  

E-Print Network (OSTI)

We explore the mechanisms for an efficient light trapping structure for thin-film silicon solar cells. The design combines a distributed Bragg reflector (DBR) and periodic gratings. Using photonic band theories and numerical ...

Sheng, Xing

104

Abstract LB-258: Neutrophil extracellular traps sequester circulating tumor cells via beta 1 integrin mediated interactions  

Science Journals Connector (OSTI)

...have previously demonstrated that Neutrophil extracellular traps (NETs), composed of extracellular neutrophil-derived DNA webs, are intricately implicated in this process by directly binding and capturing circulating tumor cells. However, the mechanisms...

Sara Najmeh; Jonathan Cools-Lartigue; Stephen Gowing; Jonahan Spicer; Braedon McDonald; Betty Giannias; France Bourdeau; Paul Kubes; Lorenzo Edwin Ferri

2014-10-01T23:59:59.000Z

105

Heating rates in collisionally opaque alkali-metal atom traps: Role of secondary collisions  

Science Journals Connector (OSTI)

Grazing collisions with background gas are the major cause of trap loss and trap heating in atom traps. To first order, these effects do not depend on the trap density. In collisionally opaque trapped atom clouds, however, scattered atoms with an energy E larger than the effective trap depth Eeff, which are destined to escape from the atom cloud, will have a finite probability for a secondary collision. This results in a contribution to the heating rate that depends on the column density ?nl? of the trapped atoms, i.e., the product of density and characteristic size of the trap. For alkali-metal atom traps, secondary collisions are quite important due to the strong long-range interaction with like atoms. We derive a simple analytical expression for the secondary heating rate, showing a dependency proportional to ?nl??Eeff1/2. When extrapolating to a vanishing column density, only primary collisions with the background gas will contribute to the heating rate. This contribution is rather small, due to the weak long-range interaction of the usual background gas species in an ultrahigh-vacuum system—He, Ne, or Ar—with the trapped alkali-metal atoms. We conclude that the transition between trap-loss collisions and heating collisions is determined by a cutoff energy 200??K<~Eeff<~400??K, much smaller than the actual trap depth E in most magnetic traps. Atoms with an energy Eeffmechanism of effective traploss in the microkelvin range of trap temperatures. We present results of secondary heating rates for the alkali-metal atoms Li through Cs as a function of the effective trap depth, the column density of the trap, and the species in the background gas. The predictions of our model are in good agreement with the experimental data of Myatt for heating rates in high-density 87Rb-atom magnetic traps at JILA, including the effect of the rf shield and the composition of the background gas. It is shown that collisions with atoms from the Oort cloud also contribute to the heating rate. For 85Rb the calculated heating rate is below the experimentally observed value at JILA, supporting the idea that inelastic collisions in the trap are the major source of heating.

H. C. W. Beijerinck

2000-11-15T23:59:59.000Z

106

Electron Trapping by Molecular Vibration  

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

Electron Trapping by Molecular Vibration Print Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

107

Electron Trapping by Molecular Vibration  

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

Electron Trapping by Molecular Vibration Print Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

108

Residence Time Effects on Arsenate Adsorption/Desorption Mechanisms on Goethite S. E. O'Reilly,* D. G. Strawn, and D. L. Sparks  

E-Print Network (OSTI)

Residence Time Effects on Arsenate Adsorption/Desorption Mechanisms on Goethite S. E. O'Reilly,* D and desorption on goethite, and to combine spectro- Xu et al., 1988). For example, arsenate sorption on scopic x and Glaubig, 1988).showed that arsenate sorption on goethite increased with time. Sorp- Goethite ( ­Fe

Sparks, Donald L.

109

Hybrid particle traps and conditioning procedure for gas insulated transmission lines  

DOE Patents (OSTI)

A gas insulated transmission line includes an outer sheath, an inner condor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping ring is disposed within the outer sheath, and the trapping ring has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the trapping ring along an arc. A support sheet having an adhesive coating thereon is secured to the trapping ring and disposed on the outer sheath within the low field region formed between the trapping ring and the outer sheath. A conditioning method used to condition the transmission line prior to activation in service comprises applying an AC voltage to the inner conductor in a plurality of voltage-time steps, with the voltage-time steps increasing in voltage magnitude while decreasing in time duration.

Dale, Steinar J. (Monroeville, PA); Cookson, Alan H. (Churchill, PA)

1982-01-01T23:59:59.000Z

110

Electron Trapping by Molecular Vibration  

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

Electron Trapping by Molecular Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally thought to be forbidden can in fact be excited in conjunction with certain types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can become temporarily trapped by the molecule before ultimately escaping, giving rise to a broad feature in the photoelectron spectrum known as a shape resonance. This process represents a novel type of symmetry-breaking phenomenon that has not been observed previously but appears to be widespread. Such coupling between electronic motion and nuclear motion becomes increasingly important as scientists learn more about the geometry and dynamics of novel chemical structures such as those found in nanodevices and transient chemical species, and the results have implications for studies that use photoelectron spectroscopy as a diagnostic tool.

111

Inertial measurement via dynamics of trapped particles  

E-Print Network (OSTI)

We describe theoretical and practical aspects of the particle trap as an inertial sensor. The insight motivating this approach is that a trapped particle acts like a mass on a spring, but the restoring forces are provided ...

Post, E. Rehmi, 1966-

2003-01-01T23:59:59.000Z

112

Carbon Nanotubes in an Optical Trap  

Science Journals Connector (OSTI)

Study of carbon nanotubes (CNTs) in a single beam optical trap (1064 nm) was done. In the optical trap, repulsion of the CNTS from the laser radiation, bubble formation, broad band...

Ramanandan, Gopika; Dharmadhikari, Aditya K; Ramachandran, Hema; Dharmadhikari, Jayasree A; Mathur, Deepak

113

Condensation of Excitons in a Trap  

Science Journals Connector (OSTI)

Condensation is observed in a gas of indirect excitons confined in an electrostatic trap. Imaging and interferometric measurements detect that excitons condense at the trap bottom and exciton spontaneous coherence emerges with lowering temperature. Below ...

A. A. High; J. R. Leonard; M. Remeika; L. V. Butov; M. Hanson; A. C. Gossard

2012-04-17T23:59:59.000Z

114

Review of Orifice Plate Steam Traps  

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

This guide was prepared to serve as a foundation for making informed decisions about when orifice plate steam traps should be considered for use in new or existing steam systems. It presents background information about different types of steam traps and defines their unique functional and operational characteristics. The advantages and disadvantages associated with using orifice plate steam traps are provided to highlight their capabilities and limitations. Finally, recommendations for using orifice plate steam traps are presented, and possible applications are identified.

115

Double Well Potentials and Quantum Phase Transitions in Ion Traps  

Science Journals Connector (OSTI)

We demonstrate that the radial degree of freedom of strings of trapped ions in the quantum regime may be prepared and controlled accurately through the variation of the external trapping potential while at the same time its properties are measurable with high spatial and temporal resolution. This provides a new testbed giving access to static and dynamical properties of the physics of quantum-many-body systems and quantum phase transitions that are hard to simulate on classical computers. Furthermore, it allows for the creation of double well potentials with experimentally accessible tunneling rates, with applications in testing the foundations of quantum physics and precision sensing.

A. Retzker; R. C. Thompson; D. M. Segal; M. B. Plenio

2008-12-30T23:59:59.000Z

116

Electron Trapping in Shear Alfvén Waves that Power the Aurora  

Science Journals Connector (OSTI)

Results from 1D Vlasov drift-kinetic plasma simulations reveal how and where auroral electrons are accelerated along Earth’s geomagnetic field. In the warm plasma sheet, electrons become trapped in shear Alfvén waves, preventing immediate wave damping. As waves move to regions with larger vTe/vA, their parallel electric field decreases, and the trapped electrons escape their influence. The resulting electron distribution functions compare favorably with in situ observations, demonstrating for the first time a self-consistent link between Alfvén waves and electrons that form aurora.

Clare E. J. Watt and Robert Rankin

2009-01-26T23:59:59.000Z

117

Electron Trapping in Shear Alfven Waves that Power the Aurora  

SciTech Connect

Results from 1D Vlasov drift-kinetic plasma simulations reveal how and where auroral electrons are accelerated along Earth's geomagnetic field. In the warm plasma sheet, electrons become trapped in shear Alfven waves, preventing immediate wave damping. As waves move to regions with larger v{sub Te}/v{sub A}, their parallel electric field decreases, and the trapped electrons escape their influence. The resulting electron distribution functions compare favorably with in situ observations, demonstrating for the first time a self-consistent link between Alfven waves and electrons that form aurora.

Watt, Clare E. J.; Rankin, Robert [University of Alberta, Edmonton, Alberta (Canada)

2009-01-30T23:59:59.000Z

118

Optical trapping for undergraduates D. C. Appleyard  

E-Print Network (OSTI)

Optical trapping for undergraduates D. C. Appleyard Department of Biological Engineering September 2006 The detailed design of a robust and inexpensive optical trap system is presented. The system experimental modules are described to cover basic concepts in optical trapping and biophysics at a level

Lang, Matthew

119

Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems  

E-Print Network (OSTI)

Finite element simulations of hydrodynamic trapping in microfluidic particle- trap array systems;Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems Xiaoxiao) simulation is a powerful tool in the design and implementation of microfluidic systems, especially

Nehorai, Arye

120

Noise and microresonance of critical current in Josephson junction induced by Kondo trap states  

E-Print Network (OSTI)

We analyze the impact of trap states in the oxide layer of a superconducting tunnel junctions, on the fluctuation of the Josephson critical current, thus on coherence in superconducting qubits. Two mechanisms are usually considered: the current blockage due to repulsion at the occupied trap states, and the noise from electrons hopping across a trap. We extend previous studies of noninteracting traps to the case where the traps have on-site electron repulsion inside one ballistic channel. The repulsion not only allows the appropriate temperature dependence of 1/f noise, but also is a control to the coupling between the computational qubit and the spurious two-level systems inside the oxide dielectric. We use second order perturbation theory which allows to obtain analytical formulae for the interacting bound states and spectral weights, limited to small and intermediate repulsions. Remarkably, it still reproduces the main features of the model as identified from the Numerical Renormalization Group. We present ...

Ansari, Mohammad H

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

`Quantum explosion' of a trapped one-dimensional Bose gas  

E-Print Network (OSTI)

We analyze free expansion of a trapped one-dimensional Bose gas after a sudden release from the confining trap potential. By using the stationary phase and local density approximations, we show that the long-time asymptotic density profile and the momentum distribution of the gas are determined by the initial distribution of Bethe rapidities (quasimomenta) and hence can be obtained from the solutions to the thermodynamic Bethe ansatz equations. For expansion from a harmonic trap, and in the limits of very weak and very strong interactions, we recover the known scaling solutions of the hydrodynamic approach corresponding to self-similar expansion. For all other power-law traps and arbitrary interaction strengths, the expansion is not self-similar and shows strong dependence on the trap anharmonicity of the shape variation of the density profile during evolution. We also characterize dynamical fermionization of an expanding cloud in terms of its first- and second-order coherences describing phase and density fluctuations.

A. S. Campbell; D. M. Gangardt; K. V. Kheruntsyan

2015-01-15T23:59:59.000Z

122

"Magic" radio-frequency dressing for trapped atomic microwave clocks  

E-Print Network (OSTI)

It has been proposed to use magnetically trapped atomic ensembles to enhance the interrogation time in microwave clocks. To mitigate the perturbing effects of the magnetic trap, "near-magic field" configurations are employed, where the involved clock transition becomes independent of the atoms potential energy to first order. Still, higher order effects are a dominating source for dephasing, limiting the perfomance of this approach. Here we propose a simple method to cancel the energy dependence to both, first and second order, using weak radio-frequency dressing. We give values for dressing frequencies, amplitudes, and trapping fields for 87Rb atoms and investigate quantitatively the robustness of these "second-order magic" conditions to variations of the system parameters. We conclude that radio-frequency dressing can suppress field-induced dephasing by at least one order of magnitude for typical experimental parameters.

Kazakov, Georgy A

2014-01-01T23:59:59.000Z

123

Single Ion Trapping For The Enriched Xenon Observatory  

E-Print Network (OSTI)

In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of ? m?? ≃ .010 eV.

Waldman, S J

2005-01-01T23:59:59.000Z

124

Electron capture by trapped Neq+ ions at very low energies  

Science Journals Connector (OSTI)

An electrostatic ion trap is used to trap Neq+ (1?q?10) ions created by a fast xenon beam passing through neon gas. Decay of a given charge state during the trapping time is due to electron-capture collisions with the ambient gas. Measurement of the decay constant versus density yields a rate constant, from which an effective cross section is derived. Neq+ + Ne (q=3-10) and Neq++Xe (q=6-10) collisions have been studied at mean collision energies in the range 1.0-70.0 eV. Marked oscillation of the effective capture cross sections with charge at fixed mean collision energies is observed. A strong velocity dependence of the effective cross section (rising as the velocity decreases) is observed for several collision pairs.

M. H. Prior; Richard Marrus; C. R. Vane

1983-07-01T23:59:59.000Z

125

Qualitative analysis of trapped Dirac fermions in graphene  

E-Print Network (OSTI)

We study the confinement of Dirac fermions in graphene and in carbon nanotubes by an external magnetic field, mechanical deformations or inhomogeneities in the substrate. By applying variational principles to the square of the Dirac operator, we obtain sufficient and necessary conditions for confinement of the quasi-particles. The rigorous theoretical results are illustrated on the realistic examples of the three classes of traps.

Vit Jakubsky; David Krejcirik

2014-05-11T23:59:59.000Z

126

Qualitative analysis of trapped Dirac fermions in graphene  

E-Print Network (OSTI)

We study the confinement of Dirac fermions in graphene and in carbon nanotubes by an external magnetic field, mechanical deformations or inhomogeneities in the substrate. By applying variational principles to the square of the Dirac operator, we obtain sufficient and necessary conditions for confinement of the quasi-particles. The rigorous theoretical results are illustrated on the realistic examples of the three classes of traps.

Vit Jakubsky; David Krejcirik

2015-01-07T23:59:59.000Z

127

Temperature-Driven Structural Phase Transition for Trapped Ions and a Proposal for its Experimental Detection  

SciTech Connect

A Wigner crystal formed with trapped ions can undergo a structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be driven solely by a change in the system's temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.

Gong Zhexuan; Lin, G.-D.; Duan, L.-M. [Department of Physics and MCTP, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2010-12-31T23:59:59.000Z

128

Temperature-Driven Structural Phase Transition for Trapped Ions and a Proposal for its Experimental Detection  

Science Journals Connector (OSTI)

A Wigner crystal formed with trapped ions can undergo a structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be driven solely by a change in the system’s temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.

Zhe-Xuan Gong; G.-D. Lin; L.-M. Duan

2010-12-29T23:59:59.000Z

129

Temperature driven structural phase transition for trapped ions and its experimental detection  

E-Print Network (OSTI)

A Wigner crystal formed with trapped ion can undergo structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be solely driven by change of the system's temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.

Zhe-Xuan Gong; G. -D. Lin; L. -M. Duan

2010-09-01T23:59:59.000Z

130

The Magnetic Noise of a DC Electric Motor — Modeling of Three-Times-Coupled Electromagnetic, Mechanical and Acoustic Phenomena  

Science Journals Connector (OSTI)

The sound power level of the magnetic noise radiated from a DC electric motor was numerically estimated for different loading conditions and two motor designs. Since the mechanism of the magnetic noise generation...

M. Furlan; M. Boltežar

2005-01-01T23:59:59.000Z

131

Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption Fine Structure (XAFS) Study  

E-Print Network (OSTI)

Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption Fine Structure (XAFS) Study A. M. Scheidegger and G. M. Lamble Metal sorption on clay and oxide in reaction rate has been attributed to metal sorption onto sites of lower reactivity, diffusion

Sparks, Donald L.

132

Residence Time Effects on P Sorption/Desorption on Ferrihydrite Understanding mechanisms of P retention/release on soil mineral surfaces is  

E-Print Network (OSTI)

Residence Time Effects on P Sorption/Desorption on Ferrihydrite Y. Arai Understanding mechanisms through macroscopic and microscopic approaches. The effect of ionic strength (0.0, 0.1, 1.0) on P sorption pH, sorption decreased ad I decreased. The effect of pH (4, 7.l5, 9.5) on P sorption kinetics

Sparks, Donald L.

133

Capturing Energy Savings with Steam Traps  

E-Print Network (OSTI)

Capturing Energy Savings with Steam Traps Richard C; Bockwinkel General Manager Armstrong Service? A Division of Armstrong International, Inc. Orlando, Florida ABSTRACT This paper will discuss the energy savings potential of steam... Engineer Steam Traps Armstrong International, Inc. Three Rivers, Michigan basis. Finally, it's important to recognize that a steam trap program will reduce steam waste> which will reduce the amount of fuel burned> which will reduce pollutants...

Bockwinkel, R. G.; French, S. A.

134

Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration  

E-Print Network (OSTI)

scale package of 2 Watts steady state power is subjected to 1000 Watts for about 1 ms, junction temperature was seen to rise 50 o C. Mercado et al. [29] did an integrated transient thermal and mechanical analysis for a molded plastic ball grid array...

Oh, Yoonchan

2005-11-01T23:59:59.000Z

135

Plant View On Reducing Steam Trap Energy Loss  

E-Print Network (OSTI)

of the steam traps are passing excess steam. This is caused by neglect of aged steam traps which have worn out and misapplication of steam traps by oversizing or using the 'wrong' type trap. Elimination of steam wastes by an effective well engineered steam trap...

Vallery, S. J.

1982-01-01T23:59:59.000Z

136

Rare-earth neutral metal injection into an electron beam ion trap plasma  

SciTech Connect

We have designed and implemented a neutral metal vapor injector on the SuperEBIT high-energy electron beam ion trap at the Lawrence Livermore National Laboratory. A horizontally directed vapor of a europium metal is created using a thermal evaporation technique. The metal vapor is then spatially collimated prior to injection into the trap. The source's form and quantity constraints are significantly reduced making plasmas out of metal with vapor pressures ?10{sup ?7} Torr at ?1000?°C more obtainable. A long pulsed or constant feed metal vapor injection method adds new flexibility by varying the timing of injection and rate of material being introduced into the trap.

Magee, E. W., E-mail: magee1@llnl.gov; Beiersdorfer, P.; Brown, G. V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

2014-11-15T23:59:59.000Z

137

Optical trapping and rotation of airborne absorbing particles with a single focused laser beam  

SciTech Connect

We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20?kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ?20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.

Lin, Jinda; Li, Yong-qing, E-mail: liy@ecu.edu [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)] [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)

2014-03-10T23:59:59.000Z

138

On the Rigorous Derivation of the 3D Cubic Nonlinear Schrödinger Equation with A Quadratic Trap  

E-Print Network (OSTI)

We consider the dynamics of the 3D N-body Schr\\"{o}dinger equation in the presence of a quadratic trap. We assume the pair interaction potential is N^{3{\\beta}-1}V(N^{{\\beta}}x). We justify the mean-field approximation and offer a rigorous derivation of the 3D cubic NLS with a quadratic trap. We establish the space-time bound conjectured by Klainerman and Machedon [30] for {\\beta} in (0,2/7] by adapting and simplifying an argument in Chen and Pavlovi\\'c [7] which solves the problem for {\\beta} in (0,1/4) in the absence of a trap.

Xuwen Chen

2012-03-31T23:59:59.000Z

139

Effect of trapping on transport coherence  

Science Journals Connector (OSTI)

Influence of a trap (sink) on exciton transfer in molecular aggregates is investigated. Memory functions entering the generalized master equations are calculated. The presence of the sink changes their analytical form. We used the sink in trimers as an example to show that for large trapping-rate parameters the rest of the system is decoupled from the sink.

Ivan Barvk and Pavel Heman

1992-02-01T23:59:59.000Z

140

Entangled states of trapped atomic ions  

Science Journals Connector (OSTI)

... typical experiment involves trapping a few ions by using a combination of static and sinusoidally oscillating electric potentials that are applied between the electrodes of a linear quadrupole, an arrangement ... Fig. 1). When the trapped ions are laser cooled, they form a linear 'string', in which the spacings are determined by a balance between the horizontal (axial) ...

Rainer Blatt; David Wineland

2008-06-18T23:59:59.000Z

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


141

The Development of a Detailed Chemical Kinetic Mechanism for Diisobutylene and Comparison to Shock Tube Ignition Times  

SciTech Connect

There is much demand for chemical kinetic models to represent practical fuels such as gasoline, diesel and aviation fuel. These blended fuels contain hundreds of components whose identity and amounts are often unknown. A chemical kinetic mechanism that would represent the oxidation of all these species with accompanying chemical reactions is intractable with current computational capabilities, chemical knowledge and manpower resources. The use of surrogate fuels is an approach to make the development of chemical kinetic mechanisms for practical fuels tractable. A surrogate fuel model consists of a small number of fuel components that can be used to represent the practical fuel and still predict desired characteristics of the practical fuel. These desired fuel characteristics may include ignition behavior, burning velocity, fuel viscosity, fuel vaporization, and fuel emissions (carbon monoxide, hydrocarbons, soot and nitric oxides). Gasoline consists of many different classes of hydrocarbons including n-alkanes, alkenes, iso-alkanes, cycloalkanes, cycloalkenes, and aromatics. One approach is to use a fuel surrogate that has a single component from each class of hydrocarbon in gasoline so that the unique molecular structure of each class is represented. This approach may lead to reliable predictions of many of the combustion properties of the practical fuel. In order to obtain a fuel surrogate mechanism, detailed chemical kinetic mechanisms must be developed for each component in the surrogate. In this study, a detailed chemical kinetic mechanism is developed for diisobutylene, a fuel intended to represent alkenes in practical fuels such as gasoline, diesel, and aviation fuel. The fuel component diisobutylene usually consists of a mixture of two conjugate olefins of iso-octane: 1- or 2-pentene, 2,4,4-trimethyl. Diisobutylene has a similar molecular structure to iso-octane, so that its kinetics offers insight into the effect of including a double bond in the carbon skeletal structure of iso-octane. There are few previous studies on diisobutylene. Kaiser et al. [1] examined the exhaust emission from a production spark ignition engine with neat diisobutylene and with it mixed with gasoline. They found the exhaust emissions of diisobutylene to be similar to that of iso-octane. They saw a significant increase in the amount of 2-methyl-1,3-butadiene measured in the exhaust of the engine. They also found appreciable amount of propene in the exhaust, but could not explain the source of this product as they did others in terms of C-C bond beta scission of alkyl radicals. Risberg et al. [2] studied a number of fuel blends to evaluate their autoignition quality for use in a homogeneous charge compression ignition engine, using diisobutylene to represent olefins in one of their test fuels. In this study, experiments on the shock tube ignition of both isomers of diisobutylene will be described. Then, the development of a detailed chemical kinetic mechanism for the two isomers of diisobutylene will be discussed.

Metcalfe, W; Curran, H J; Simmie, J M; Pitz, W J; Westbrook, C K

2005-01-21T23:59:59.000Z

142

Dynamical density functional theory with hydrodynamic interactions and colloids in unstable traps  

E-Print Network (OSTI)

A density functional theory for colloidal dynamics is presented which includes hydrodynamic interactions between the colloidal particles. The theory is applied to the dynamics of colloidal particles in an optical trap which switches periodically in time from a stable to unstable confining potential. In the absence of hydrodynamic interactions, the resulting density breathing mode, exhibits huge oscillations in the trap center which are almost completely damped by hydrodynamic interactions. The predicted dynamical density fields are in good agreement with Brownian dynamics computer simulations.

M. Rex; H. Loewen

2008-03-13T23:59:59.000Z

143

Fast transitionless expansions of Gaussian anharmonic traps for cold atoms: bang-singular-bang control  

E-Print Network (OSTI)

Combining invariant-based inverse engineering, perturbation theory, and Optimal Control Theory, we design fast, transitionless expansions of cold neutral atoms or ions in Gaussian anharmonic traps. Bounding the possible trap frequencies and using a "bang-singular-bang" control we find fast processes for a continuum of durations up to a minimum time that corresponds to a purely bang-bang (stepwise frequency constant) control.

Xiao-Jing Lu; Xi Chen; J. Alonso; J. G. Muga

2014-01-07T23:59:59.000Z

144

Trapping of Implanted He at Cu/Nb Interfaces Measured by Neutron Reflectometry  

SciTech Connect

In single crystalline metals, He is insoluble and precipitates into bubbles. In contrast, Cu-Nb multilayers show no evidence of bubble formation below a critical concentration. The conclusions of this paper are: (1) He is trapped at Cu/Nb , Cu/Mo interfaces; (2) He is trapped interstitially; (3) The interface swells {approx} 10 times; and (4) The layered structure retains despite the swell of interfaces.

Wang, Peng [Los Alamos National Laboratory; Zhernenkov, Mikhail [Applications Scientist at Nanometrics; Kashinath, Abishek [MIT; Demkowicz, Michael [MIT; Baldwin, Jon K. [Los Alamos National Laboratory; Majewski, Jaroslaw [Los Alamos National Laboratory

2012-06-20T23:59:59.000Z

145

Investigation of Aging Mechanisms in Lean NOx Traps  

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

2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C.

146

Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps  

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

2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C.

147

A quantum mechanical relation connecting time, temperature, and cosmological constant of the universe: Gamow's relation revisited as a special case  

E-Print Network (OSTI)

Considering our expanding universe as made up of gravitationally interacting particles which describe particles of luminous matter and dark matter and dark energy which is described by a repulsive harmonic potential among the points in the flat 3-space, we derive a quantum mechanical relation connecting, temperature of the cosmic microwave background radiation, age, and cosmological constant of the universe. When the cosmological constant is zero, we get back the Gamow's relation with a much better coefficient. Otherwise, our theory predicts a value of the cosmological constant $2.234 10^{-56} {\\rm {cm^{-2}}}$ when the present values of cosmic microwave background temperature of 2.728 K and age of the universe 14 billion years are taken as input.

Mishra, S

2007-01-01T23:59:59.000Z

148

Microfabricated Renewable Beads-Trapping/Releasing Flow Cell...  

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

Microfabricated Renewable Beads-TrappingReleasing Flow Cell for Rapid Antigen-Antibody Reaction in Chemiluminescent Immunoassay Microfabricated Renewable Beads-TrappingReleasing...

149

Characterization of Trapped Lignin-Degrading Microbes in Tropical...  

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

Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Abstract: Lignin is often the most...

150

H2-Assisted NOx Traps: Test Cell Results Vehicle Installations...  

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

H2-Assisted NOx Traps: Test Cell Results Vehicle Installations H2-Assisted NOx Traps: Test Cell Results Vehicle Installations 2003 DEER Conference Presentation: ArvinMeritor...

151

H2-Assisted NOx Traps: Test Cell Results Vehicle Installations  

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

Sam Crane August 28, 2003 H 2 -Assisted NOx Traps: Test Cell Results Vehicle Installations 2 Project Objectives * Determine Advantages of H 2 Assisted NO x Trap Regeneration *...

152

NOx Adsorber (Lean NOx Trap) Fundamentals (Agreement #10049 ...  

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

NOx Adsorber (Lean NOx Trap) Fundamentals (Agreement 10049 - PNNL Project 47120) NOx Adsorber (Lean NOx Trap) Fundamentals (Agreement 10049 - PNNL Project 47120) Presentation...

153

Modeling the Regeneration Chemistry of Lean NOx Traps | Department...  

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

the Regeneration Chemistry of Lean NOx Traps Modeling the Regeneration Chemistry of Lean NOx Traps Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored...

154

Steam Trap Maintenance as a Profit Center  

E-Print Network (OSTI)

the Eighteenth Industrial Energy Technology Conference, Houston, TX, April 17-18, 1996 EXCUSES Everybody thinks his or her steam trap maintenance is good. Surveysl have shown the following are the most popular excuses encountered when managers are confronted... for steam traps. 192 ESL-IE-96-04-28 Proceedings from the Eighteenth Industrial Energy Technology Conference, Houston, TX, April 17-18, 1996 5. Set up a trap maintenance program C. Prepare and present a report to that will: management on the results...

Bouchillon, J. L.

155

Compact RF resonator for cryogenic ion traps  

E-Print Network (OSTI)

We report on the investigation and implementation of a lumped-component, radio-frequency resonator used in a cryogenic vacuum environment to drive an ion trap. The resonator was required to achieve the voltages necessary to trap (about 100 V), while dissipating as little power as possible (< 250 mW). Ultimately a voltage gain of 100 was measured at 5.7 K. Single calcium ions were confined in a trap driven by this device, providing proof of successful resonator operation at low temperature.

D. Gandolfi; M. Niedermayr; M. Kumph; M. Brownnutt; R. Blatt

2012-04-23T23:59:59.000Z

156

In-situ, Real-Time Monitoring of Mechanical and Chemical Structure Changes in a V2O5 Battery Electrode Using a MEMS Optical Sensor  

SciTech Connect

This work presents the first demonstration of a MEMS optical sensor for in-situ, real-time monitoring of both mechanical and chemical structure evolutions in a V2O5 lithium-ion battery (LIB) cathode during battery operation. A reflective membrane forms one side of a Fabry-Perot (FP) interferometer, while the other side is coated with V2O5 and exposed to electrolyte in a half-cell LIB. Using one microscope and two laser sources, both the induced membrane deflection and the corresponding Raman intensity changes are observed during lithium cycling. Results are in good agreement with the expected mechanical behavior and disorder change of the V2O5 layers, highlighting the significant potential of MEMS as enabling tools for advanced scientific investigations.

Jung, H. [University of Maryland; Gerasopoulos, K. [University of Maryland; Gnerlich, Markus [University of Maryland; Talin, A. Alec [Sandia National Laboratories; Ghodssi, Reza [University of Maryland

2014-06-01T23:59:59.000Z

157

Nonlinear Spectroscopy of Trapped Ions  

E-Print Network (OSTI)

Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and has become a highly successful method for experiments in chemical physics. Current quantum optical experiments approach system sizes and levels of complexity which require the development of efficient techniques to assess spectral and dynamical features with scalable experimental overhead. However, established methods from optical spectroscopy of macroscopic ensembles cannot be applied straightforwardly to few-atom systems. Based on the ideas proposed in [M. Gessner et al. New J. Phys. 16 092001 (2014)], we develop a diagrammatic approach to construct nonlinear measurement protocols for controlled quantum systems and discuss experimental implementations with trapped ion technology in detail. These methods in combination with distinct features of ultra-cold matter systems allow us to monitor and analyze excitation dynamics in both the electronic and vibrational degrees of freedom. They are independent of system size, and can therefore reliably probe systems where, e.g., quantum state tomography becomes prohibitively expensive. We propose signals that can probe steady state currents, detect the influence of anharmonicities on phonon transport, and identify signatures of chaotic dynamics near a quantum phase transition in an Ising-type spin chain.

Frank Schlawin; Manuel Gessner; Shaul Mukamel; Andreas Buchleitner

2014-10-07T23:59:59.000Z

158

Nuclear spin qubits in a trapped-ion quantum computer  

E-Print Network (OSTI)

Physical systems must fulfill a number of conditions to qualify as useful quantum bits (qubits) for quantum information processing, including ease of manipulation, long decoherence times, and high fidelity readout operations. Since these conditions are hard to satisfy with a single system, it may be necessary to combine different degrees of freedom. Here we discuss a possible system, based on electronic and nuclear spin degrees of freedom in trapped ions. The nuclear spin yields long decoherence times, while the electronic spin, in a magnetic field gradient, provides efficient manipulation, and the optical transitions of the ions assure a selective and efficient initialization and readout.

M. Feng; Y. Y. Xu; F. Zhou; D. Suter

2009-04-26T23:59:59.000Z

159

Triplet Transport to and Trapping by Acceptor End Groups on Conjugated  

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

Triplet Transport to and Trapping by Acceptor End Groups on Conjugated Triplet Transport to and Trapping by Acceptor End Groups on Conjugated Polyfluorene Chains Paiboon Sreearunothai, Alexis Estrada, Sadayuki Asaoka, Marta Kowalczyk, Seogjoo Jang, Andrew R. Cook, Jack M. Preses and John R. Miller J. Phys. Chem. C 115, 19569-19577 (2011). [Find paper at ACS Publications] Abstract: Triplet excited states created in polyfluorene (pF) molecules having average lengths up to 170 repeat units were transported to and captured by trap groups at the ends in less ~40 ns. Almost all of the triplets attached to the chains reached the trap groups, ruling out the presence of substantial numbers of defects that prevent transport. The transport yields a diffusion coefficient D of at least 3 x 10-4 cm2 s-1, which is 30 times typical molecular diffusion and close to a value for triplet transport

160

Trapping of microorganism using cylindrical standing ultrasound waves and its application to water purification  

Science Journals Connector (OSTI)

In biological fields it is known that the ultrasound is useful for trapping of biological cells or microorganism. Recently several experimental results of micro-particle trapping by acoustic standing wave fields which are formed by plane waves have been reported. In this study we confirm that the standing waves by a cylindrical ultrasonic transducer can trap and aggregate the microorganism such as green algae chlorella etc. Those microorganism were trapped at specific positions determined by acoustic pressure distribution and the density of aggregation is increased according to the lapse time after the transducer operating. The dense colony of microorganism is easily filtered out by a sieve. A water purification system using this phenomenon was designed and the efficiency was verified by considering the density change of the microorganism after the ultrasonic treatment. Consequently it is shown that the standing wave in a cylindrical transducer can be applied to water purification.

Hae-Rang Hwang; Yonggang Cao; Jungsoon Kim; Moojoon Kim; Kang-Lyeol Ha

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Novel light trapping scheme for thin crystalline cells utilizing deep structures on both wafer sides  

SciTech Connect

A new light trapping structure is presented with trapping capabilities comparable to or better than those of the perpendicular grooves structure. The new structure traps a larger fraction of rays for 8--80 passes than the perpendicular grooves structure. The average path length enhancement is about 62 times the average thickness. The structure consists of deep ({approximately}200 {micro}m) inverted pyramids on the front side and deep ({approximately}200 {micro}m) truncated pyramids with eight sides on the back. The structure is realized in crystalline silicon by wet chemical etching using potassium hydroxide (KOH) and isopropanol (IPA). A process for creating thin solar cells with this light trapping scheme is described. The process includes only two main photolithographic steps and features a self aligned front metallization. The process uses 250 {micro}m wafers to create cells that on average are about 70 {micro}m thick.

Jorgensen, A.M.; Clausen, T.; Leistiko, O. [Technical Univ. of Denmark, Lyngby (Denmark). Microelectronics Centre

1997-12-31T23:59:59.000Z

162

The Canadian Penning Trap Spectrometer at Argonne  

Science Journals Connector (OSTI)

The Canadian Penning Trap (CPT) mass spectrometer is a device used for high-precision mass measurements on short-lived isotopes. It is located at the ATLAS superconducting heavy-ion linac facility where a nove...

G. Savard; R. C. Barber; C. Boudreau…

2001-01-01T23:59:59.000Z

163

The Canadian Penning Trap Spectrometer at Argonne  

Science Journals Connector (OSTI)

The Canadian Penning Trap (CPT) mass spectrometer is a device used for high-precision mass measurements on short-lived isotopes. It is located at the ATLAS superconducting heavy-ion linac facility where a nove...

G. Savard; R. C. Barber; C. Boudreau; F. Buchinger; J. Caggiano…

164

pH-biased isoelectric trapping separations  

E-Print Network (OSTI)

The classical isoelectric trapping (IET) technique, using the multicompartment electrolyzer (MCE), has been one of the most successful electrophoretic techniques in preparative-scale protein separations. IET is capable of achieving high resolution...

Shave, Evan Eric

2006-10-30T23:59:59.000Z

165

Shale gas is natural gas trapped inside  

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

Shale gas is natural gas trapped inside formations of shale - fine grained sedimentary rocks that can be rich sources of petroleum and natural gas. Just a few years ago, much of...

166

Scaling the Ion Trap Quantum Processor  

Science Journals Connector (OSTI)

...atomic ion species to act as "refrigerator" ions to quench the...scale beyond the QCCD in a modular architecture, one can link separate...trapped ion technology. (A) Modular distributed...A major challenge in both modular quantum computer...

C. Monroe; J. Kim

2013-03-08T23:59:59.000Z

167

FEMP-FTA--Steam Trap Performance Assessment  

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

Steam Trap Function Steam Trap Function Steam traps are automatic valves used in every steam system to remove conden- sate, air, and other non-condensable gases while preventing or minimizing the passing of steam. If condensate is allowed to collect, it reduces the flow capacity of steam lines and the thermal capacity of heat transfer equipment. In addition, excess condensate can lead to "water hammer," with potentially destructive and dangerous results. Air that remains after system startup reduces steam pressure and temperature and may also reduce the thermal capacity of heat transfer equipment. Non-condensable gases, such as oxygen and carbon dioxide, cause corrosion. Steam that passes through the trap provides no heating ser- vice. This effectively reduces the heating capacity

168

Energy Savings Through Steam Trap Management  

E-Print Network (OSTI)

Energy Savings through Steam Trap Management Chris Gibbs, Account Manager, Armstrong International, Inc., Three Rivers, MI ESL-IE-08-05-08 Proceedings from theThirtieth Industrial Energy Technology Conference...-based steam trap management application developed by Armstrong International. The application calculates steam loss, fuel loss, dollar loss and CO 2 emission generation. The database allows for trend analysis, automatic energy report generation...

Gibbs, C.

2008-01-01T23:59:59.000Z

169

Muon trapping at monovacancies in iron  

Science Journals Connector (OSTI)

Positive-muon—spin-rotation experiments were performed on electron irradiated iron. A new defect-associated frequency is observed which is assigned to muons trapped at monovacancies. The hyperfine field at the vacancy site is -0.956 T at 140 K. The diffusion constant for ?+ in iron deduced from the trapping rate follows an Arrhenius law with an activation energy of 38±3 meV between 90 and 190 K.

A. Möslang; H. Graf; G. Balzer; E. Recknagel; A. Weidinger; Th. Wichert; R. I. Grynszpan

1983-03-01T23:59:59.000Z

170

Real-Time Measurement of Diesel Trap Efficiency | Department...  

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

Update on 2007 Diesel Particulate Measurement Research 2007 Diesel Particulate Measurement Research (E-66 Project) Evaluation of the European PMP Methodologies Using...

171

On the Mechanical Interaction of Light With Homogeneous Liquids  

E-Print Network (OSTI)

We investigate one of the consequences of the three competing models describing the mechanical interaction of light with a dielectric medium. According to both the Abraham and Minkowski models the time-averaged force density is zero inside a homogeneous dielectric, whereas the induced-current Lorentz force model predicts a non-zero force density. We argue that the latter force, if exists, could drive a hydrodynamic flow inside a homogeneous fluid. Our numerical experiments show that such flows have distinct spatial patterns and may influence the dynamics of particles in a water-based single-beam optical trap.

de Reus, Michiel

2013-01-01T23:59:59.000Z

172

Mobility and trapping of hydrogen in high-strength steel Vucko Flavien, Aoufi Asdin, Bosch Cdric, Delafosse David,  

E-Print Network (OSTI)

detrimental to the mechanical properties of steels [1,2]. The sensitivity to hydrogen embrittlement increases are due to the presence of hydrogen. Hydrogen embrittlement mechanisms are closely linked to the mobilityMobility and trapping of hydrogen in high-strength steel Vucko Flavien, Aoufi Asdin, Bosch Cédric

Paris-Sud XI, Université de

173

Solar light trapping in slanted conical-pore photonic crystals: Beyond statistical ray trapping  

E-Print Network (OSTI)

Solar light trapping in slanted conical-pore photonic crystals: Beyond statistical ray trapping of AIP content is subject to the terms at: http://jap.aip.org/about/rights_and_permissions #12;Solar Street, Toronto, Ontario M5S 1A7, Canada (Received 8 October 2012; accepted 3 April 2013; published

John, Sajeev

174

Trapped-Particle Instability Leading to Bursting in Stimulated Raman Scattering Simulations  

SciTech Connect

Nonlinear, kinetic simulations of Stimulated Raman Scattering (SRS) for laser-fusion-relevant conditions present a bursting behavior. Different explanations for this regime has been given in previous studies: Saturation of SRS by increased nonlinear Landau damping [K. Estabrook et al., Phys. Fluids B 1 (1989) 1282] and detuning due to the nonlinear frequency shift of the plasma wave [H.X. Vu et al., Phys. Rev. Lett. 86 (2001) 4306]. Another mechanism, also assigning a key role to the trapped electrons, is proposed here: The break-up of the plasma wave through the trapped-particle instability.

S. Brunner; E. Valeo

2001-11-08T23:59:59.000Z

175

Photonic assisted light trapping integrated in ultrathin crystalline silicon solar cells by nanoimprint lithography  

E-Print Network (OSTI)

We report on the fabrication of two-dimensional periodic photonic nanostructures by nanoimprint lithography and dry etching, and their integration into a 1-{\\mu}m-thin mono-crystalline silicon solar cell. Thanks to the periodic nanopatterning, a better in-coupling and trapping of light is achieved, resulting in an absorption enhancement. The proposed light trapping mechanism can be explained as the superposition of a graded index effect and of the diffraction of light inside the photoactive layer. The absorption enhancement is translated into a 23% increase in short-circuit current, as compared to the benchmark cell, resulting in an increase in energy-conversion efficiency.

Trompoukis, Christos; Depauw, Valérie; Gordon, Ivan; Poortmans, Jef; 10.1063/1.4749810.

2012-01-01T23:59:59.000Z

176

Equilibrium state of a trapped two-dimensional Bose gas  

Science Journals Connector (OSTI)

We study experimentally and numerically the equilibrium density profiles of a trapped two-dimensional Rb87 Bose gas and investigate the equation of state of the homogeneous system using the local density approximation. We find a clear discrepancy between in situ measurements and quantum Monte Carlo simulations, which we attribute to a nonlinear variation of the optical density of the atomic cloud with its spatial density. However, good agreement between experiment and theory is recovered for the density profiles measured after time of flight, taking advantage of their self-similarity in a two-dimensional expansion.

Steffen P. Rath, Tarik Yefsah, Kenneth J. Günter, Marc Cheneau, Rémi Desbuquois, Markus Holzmann, Werner Krauth, and Jean Dalibard

2010-07-12T23:59:59.000Z

177

Ball-grid array architecture for microfabricated ion traps  

E-Print Network (OSTI)

State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with $^{40}$Ca$^+$ ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with $^{171}$Yb$^+$ ions in a second BGA trap.

Nicholas D. Guise; Spencer D. Fallek; Kelly E. Stevens; K. R. Brown; Curtis Volin; Alexa W. Harter; Jason M. Amini; Robert E. Higashi; Son Thai Lu; Helen M. Chanhvongsak; Thi A. Nguyen; Matthew S. Marcus; Thomas R. Ohnstein; Daniel W. Youngner

2014-12-19T23:59:59.000Z

178

Charge trapping in imidazolium ionic liquids  

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

trapping in imidazolium ionic liquids trapping in imidazolium ionic liquids I. A. Shkrob and J. F. Wishart J. Phys. Chem. B 113, 5582-5592 (2009). [Find paper at ACS Publications] or use ACS Articles on Request Abstract: Room-temperature ionic liquids (ILs) are a promising class of solvents for applications ranging from photovoltaics to solvent extractions. Some of these applications involve the exposure of the ILs to ionizing radiation, which stimulates interest in their radiation and photo- chemistry. In the case of ILs consisting of 1,3-dialkylimidazolium cations and hydrophobic anions, ionization, charge transfer and redox reactions yield charge-trapped species thought to be radicals resulting from neutralization of the constituent ions. Using computational chemistry methods and the recent results on electron spin resonance (ESR) and transient absorption

179

Thermal electric vapor trap arrangement and method  

DOE Patents (OSTI)

A technique for trapping vapor within a section of a tube is disclosed herein. This technique utilizes a conventional, readily providable thermal electric device having a hot side and a cold side and means for powering the device to accomplish this. The cold side of this device is positioned sufficiently close to a predetermined section of the tube and is made sufficiently cold so that any condensable vapor passing through the predetermined tube section is condensed and trapped, preferably within the predetermined tube section itself. 4 figs.

Alger, T.

1988-03-15T23:59:59.000Z

180

Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil  

E-Print Network (OSTI)

Characterization of Trapped Lignin-Degrading Microbes inCharacterization of Trapped Lignin-Degrading Microbes inCharacterization of Trapped Lignin-Degrading Microbes in

DeAngelis, Kristen

2012-01-01T23:59:59.000Z

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


181

Auxiliary ECR heating system for the gas dynamic trap  

SciTech Connect

Physics aspects of a new system for electron cyclotron resonance heating (ECRH) at the magnetic mirror device Gas Dynamic Trap (GDT, Budker Institute, Novosibirsk) are discussed. This system based on two 400 kW/54.5 GHz gyrotrons is aimed at increasing the electron temperature up to the range 250-350 eV for improved energy confinement of hot ions. The key physical issue of the GDT magnetic field topology is that conventional ECRH geometries are not accessible. The proposed solution is based on a peculiar effect of radiation trapping in inhomogeneous magnetized plasma. Under specific conditions, oblique launch of gyrotron radiation results in generation of right-hand-polarized (R) electromagnetic waves propagating with high N{sub Double-Vertical-Line Double-Vertical-Line} in the vicinity of the cyclotron resonance layer, which leads to effective single-pass absorption of the injected microwave power. In the present paper, we investigate numerically an optimized ECRH scenario based on the proposed mechanism of wave propagation and discuss the design of the ECRH system, which is currently under construction at the Budker Institute.

Shalashov, A. G.; Gospodchikov, E. D.; Smolyakova, O. B.; Malygin, V. I. [Institute of Applied Physics of the Russian Academy of Sciences, Ulyanova St. 46, 603950 Nizhny Novgorod (Russian Federation); Bagryansky, P. A. [Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences, Akademika Lavrentieva Prospect 11, 630090 Novosibirsk (Russian Federation); Thumm, M. [Institut fuer Hochfrequenztechnik und Elektronik, Karlsruhe Institut fuer Technologie, Engesserstrasse 5, 76131 Karlsruhe (Germany)

2012-05-15T23:59:59.000Z

182

Quantum Stochastic Heating of a Trapped Ion  

E-Print Network (OSTI)

The resonant heating of a harmonically trapped ion by a standing-wave light field is described as a quantum stochastic process combining a coherent Schroedinger evolution with Bohr-Einstein quantum jumps. Quantum and semi-quantum treatments are compared.

L. Horvath; R. Fisher; M. J. Collett; H. J. Carmichael

2007-11-09T23:59:59.000Z

183

Magneto-Optic Trapping of 210Fr  

Science Journals Connector (OSTI)

The alkali element francium has no stable isotopes and has eluded extensive study because sufficient quantities have not been available for detailed investigations. More than 1000 210Fr atoms have now been contained in a magneto-optic trap. This number is sufficient to allow extensive studies of Fr atomic properties that are necessary input for future tests of fundamental interactions.

J. E. Simsarian; A. Ghosh; G. Gwinner; L. A. Orozco; G. D. Sprouse; P. A. Voytas

1996-05-06T23:59:59.000Z

184

Efficient light-trapping nanostructures in thin silicon solar cells  

E-Print Network (OSTI)

We examine light-trapping in thin crystalline silicon periodic nanostructures for solar cell applications. Using group theory, we show that light-trapping can be improved over a broad band when structural mirror symmetry ...

Han, Sang Eon

185

Carbon dioxide dissolution in structural and stratigraphic traps  

E-Print Network (OSTI)

The geologic sequestration of carbon dioxide (CO[subscript 2]) in structural and stratigraphic traps is a viable option to reduce anthropogenic emissions. While dissolution of the CO[subscript 2] stored in these traps ...

Hesse, M. A.

186

Energy Conservation Thru Steam Trap Surveys and Preventive Maintenance Programs  

E-Print Network (OSTI)

ENERGY CONSERVATION THRU STEAM TRAP SURVEYS AND PREVENTIVE MAINTENANCE PROGRAMS Terry Boynton, Armstrong, Three Rivers, Mich. Bob Dewhirst, Armstrong, New Braunfels, Texas. This paper will deal with steam trap surveys and preventive maintenance...

Boynton, T.; Dewhirst, B.

1980-01-01T23:59:59.000Z

187

Effective Steam Trap Selection/Maintenance - Its Payback  

E-Print Network (OSTI)

In oil refineries and petrochemical plants large number of steam traps are used to discharge condensate from steam mains, tracers and process equipment. Early efforts on steam traps focused almost exclusively on their selection and sizing...

Garcia, E.

1984-01-01T23:59:59.000Z

188

In-Vacuum Active Electronics for Microfabricated Ion Traps  

E-Print Network (OSTI)

The advent of microfabricated ion traps for the quantum information community has allowed research groups to build traps that incorporate an unprecedented number of trapping zones. However, as device complexity has grown, the number of digital-to-analog converter (DAC) channels needed to control these devices has grown as well, with some of the largest trap assemblies now requiring nearly one hundred DAC channels. Providing electrical connections for these channels into a vacuum chamber can be bulky and difficult to scale beyond the current numbers of trap electrodes. This paper reports on the development and testing of an in-vacuum DAC system that uses only 9 vacuum feedthrough connections to control a 78-electrode microfabricated ion trap. The system is characterized by trapping single and multiple $^{40}$Ca$^+$ ions. The measured axial mode stability, ion heating rates, and transport fidelities for a trapped ion are comparable to systems with external(air-side) commercial DACs.

Nicholas D. Guise; Spencer D. Fallek; Harley Hayden; C-S Pai; Curtis Volin; K. R. Brown; J. True Merrill; Alexa W. Harter; Jason M. Amini; Lisa M. Lust; Kelly Muldoon; Doug Carlson; Jerry Budach

2014-06-02T23:59:59.000Z

189

Single microbe trap and release in sub-microfluidics. | EMSL  

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

Single microbe trap and release in sub-microfluidics. Single microbe trap and release in sub-microfluidics. Abstract: Lab-on-a-chip systems have substantially impacted the way...

190

The Rajahmundry Traps, Andhra Pradesh: Evaluation of their petrogenesis relative to the Deccan Traps  

Science Journals Connector (OSTI)

Geochemical and geochronological data for rocks from the Rajahmundry Traps, are evaluated for possible correlation with the main Deccan province. Lava flows are found on both banks of the Godavari River and co...

Ajoy K. Baksi

2001-12-01T23:59:59.000Z

191

Physical process Mechanical mechanisms  

E-Print Network (OSTI)

1 Physical process Generation · Mechanical mechanisms F = m·a · Electric/Magnetic mechanisms F ­ Quadrupoles......shear stress fluctuations ­ High order poles...... phys. interpretation difficult Governing

Berlin,Technische Universität

192

E B UNA-TRAP FISHERY E E ITERRANEAN SEA  

E-Print Network (OSTI)

of the bag of the trap to concentrate the tuna prior to capture. Photo supplied by Dr. Alonzo Palau, Genova

193

Nano-photonic Light Trapping In Thin Film Solar Dennis M. Callahan Jr.  

E-Print Network (OSTI)

Nano-photonic Light Trapping In Thin Film Solar Cells Thesis by Dennis M. Callahan Jr. In Partial. Jeremy Munday for helping me get started on the thin-film GaAs project and for all the time we spent to thank Dr. Jonathan Grandidier for working closely with me for a couple years on the nano sphere solar

Winfree, Erik

194

Photo-detection using Bose-condensed atoms in a micro trap  

E-Print Network (OSTI)

A model of photo-detection using a Bose--Einstein condensate in an atom-chip based micro trap is analyzed. Atoms absorb photons from the incident light field, receive part of the photon momentum and leave the trap potential. Upon counting of escaped atoms within predetermined time intervals, the photon statistics of the incident light is mapped onto the atom-count statistics. Whereas traditional photo-detection theory treats the emission centers of photo electrons as distinguishable, here the centers of escaping atoms are condensed and thus indistinguishable atoms. From this an enhancement of the photon-number resolution as compared to the commonly known counting formula is derived.

S. Wallentowitz; A. B. Klimov

2008-05-24T23:59:59.000Z

195

Nonlinear interaction of two trapped-mode resonances in a bilayer "fish-scale" metamaterial  

E-Print Network (OSTI)

We report on a bistable light transmission through a bilayer "fish-scale" (meander-line) metamaterial. It is demonstrated that an all-optical switching may be achieved nearly the frequency of the high-quality-factor Fano-shaped trapped-mode resonance excitation. The nonlinear interaction of two closely spaced trapped-mode resonances in the bilayer structure composed with a Kerr-type nonlinear dielectric slab is analyzed in both frequency and time domains. It is demonstrated that these two resonances react differently on the applied intense light which leads to destination of a multistable transmission.

Tuz, Vladimir R; Mladyonov, Pavel L; Prosvirnin, Sergey L; Novitsky, Andrey V

2014-01-01T23:59:59.000Z

196

Counting Individual Ca41 Atoms with a Magneto-Optical Trap  

Science Journals Connector (OSTI)

Atom trap trace analysis, a novel method based upon laser trapping and cooling, is used to count individual atoms of Ca41 present in biomedical samples with isotopic abundance levels between 10-8 and 10-10. The method is calibrated against resonance ionization mass spectrometry, demonstrating good agreement between the two methods. The present system has a counting efficiency of 2×10-7. Within 1 h of observation time, its 3-? detection limit on the isotopic abundance of Ca41 reaches 4.5×10-10.

I. D. Moore; K. Bailey; J. Greene; Z.-T. Lu; P. Müller; T. P. O’Connor; Ch. Geppert; K. D. A. Wendt; L. Young

2004-04-14T23:59:59.000Z

197

Rotating-radio-frequency ion traps T. Hasegawa*  

E-Print Network (OSTI)

rf ion trap, the rotating-radio-frequency rotating-rf trap, in which the motion of a charged particleRotating-radio-frequency ion traps T. Hasegawa* Department of Physics, Keio University, Kanagawa and Technology, Boulder, Colorado 80305, USA Received 9 July 2005; published 20 October 2005 We discuss a radio-frequency

198

Magnetic trapping of metastable 3 P2 atomic strontium  

E-Print Network (OSTI)

Magnetic trapping of metastable 3 P2 atomic strontium S. B. Nagel, C. E. Simien, S. Laha, P. Gupta trapping of metastable 3 P2 atomic strontium. Atoms are cooled in a magneto-optical trap MOT operating cooling on such a transition in strontium may lead to a fast and efficient route to all-optical quantum

Killian, Thomas C.

199

Fundamental limit of nanophotonic light trapping in solar cells  

E-Print Network (OSTI)

Fundamental limit of nanophotonic light trapping in solar cells Zongfu Yu1 , Aaswath Raman and is becoming increasingly urgent for current solar cell research. The standard theory of light trapping) Establishing the fundamental limit of nanophotonic light-trapping schemes is of paramount importance

Fan, Shanhui

200

High voltage gas insulated transmission line with continuous particle trapping  

DOE Patents (OSTI)

This invention provides a novel high voltage gas insulated transmission line utilizing insulating supports spaced at intervals with snap-in means for supporting a continuous trapping apparatus and said trapping apparatus having perforations and cutouts to facilitate trapping of contaminating particles and system flexibility.

Cookson, Alan H. (Pittsburgh, PA); Dale, Steinar J. (Monroeville, PA)

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Trapped-ion antennae for the transmission of quantum information  

Science Journals Connector (OSTI)

... Here this interaction is explored using ions or ion strings held in two separate potential wells of a linear segmented ion trap (Fig. 1 ... segmented ion trap (Fig. 1), where the interacting dipoles are produced by the oscillating charges. As the dipole–dipole interaction decreases rapidly with trap separation, it is advantageous ...

M. Harlander; R. Lechner; M. Brownnutt; R. Blatt; W. Hänsel

2011-02-23T23:59:59.000Z

202

In-trap decay spectroscopy with the TITAN facility at TRIUMF  

E-Print Network (OSTI)

A novel in-trap decay spectroscopy facility has been developed and constructed for use with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). This apparatus consists of an open-access spectroscopy ion-trap, which is surrounded radially with up to seven low-energy planar Si(Li) detectors. The ion-trap environment allows for the detection of low-energy photons by providing backing-free storage of the radioactive ions, while guiding decay particles from the trap center via the strong (up to 6 T) magnetic field. Excellent ion confinement is also facilitated by the use of an intense electron beam which provides storage times of minutes or more without ion loss. These advantages, along with careful monitoring and control, provide a significant increase in sensitivity for the detection of X-rays from the electron-capture process. The design, development, and commissioning of this apparatus are presented and the future of the device and experimental technique are discussed.

Leach, K G; Lennarz, A; Brunner, T; Gallant, A T; Good, M; Klawitter, R; Kwiatkowski, A A; Ma, T; Macdonald, T D; Seeraji, S; Simon, M C; Andreoiu, C; Dilling, J; Frekers, D

2014-01-01T23:59:59.000Z

203

In-trap decay spectroscopy with the TITAN facility at TRIUMF  

E-Print Network (OSTI)

A novel in-trap decay spectroscopy facility has been developed and constructed for use with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). This apparatus consists of an open-access spectroscopy ion-trap, which is surrounded radially with up to seven low-energy planar Si(Li) detectors. The ion-trap environment allows for the detection of low-energy photons by providing backing-free storage of the radioactive ions, while guiding decay particles from the trap center via the strong (up to 6 T) magnetic field. Excellent ion confinement is also facilitated by the use of an intense electron beam which provides storage times of minutes or more without ion loss. These advantages, along with careful monitoring and control, provide a significant increase in sensitivity for the detection of X-rays from the electron-capture process. The design, development, and commissioning of this apparatus are presented and the future of the device and experimental technique are discussed.

K. G. Leach; A. Grossheim; A. Lennarz; T. Brunner; J. R. Crespo López-Urrutia; A. T. Gallant; M. Good; R. Klawitter; A. A. Kwiatkowski; T. Ma; T. D. Macdonald; S. Seeraji; M. C. Simon; C. Andreoiu; J. Dilling; D. Frekers

2014-05-28T23:59:59.000Z

204

The laser ion source trap for highest isobaric selectivity in online exotic isotope production  

SciTech Connect

The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step after complete characterization is the construction and installation of the radiation-hard final trap structure and its first online application.

Schwellnus, F.; Gottwald, T.; Mattolat, C.; Wendt, K. [Institut fuer Physik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Blaum, K. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Catherall, R.; Crepieux, B.; Fedosseev, V.; Marsh, B.; Rothe, S.; Stora, T. [CERN, CH-1211 Geneva 23 (Switzerland); Kluge, H.-J. [GSI, Planckstrasse 1, D-64291 Darmstadt (Germany)

2010-02-15T23:59:59.000Z

205

Energy Savings with Computerized Steam Trap Maintenance Program  

E-Print Network (OSTI)

by Armstrong International, Inc. Five other manufacturers each have about a 5% share of the tmp population, and about 5 more account for the remaining steam traps. 6,430 STEAM TRAPS COLl3Il~) FIGURE 3 - Steam trap population by application. 8,430 STEAM... standardized using the inverted bucket steam trap made by Armstrong International, Inc. "or equal", with approval, wherever applicable and sensible. I believe the inverted bucket steam trap is the best one for this. The selection of a good manufacturer...

Klidzejs, A. M.

206

Steam Trap Testing and Evaluation: An Actual Plant Case Study  

E-Print Network (OSTI)

on there is a hydraul ic shock in the forn! of a water hammer. The standard trap used at the Olin-Joliet Plant is an Armstrong carbon steel inverted bucket. The hydraulic shock has not only broken the valve assembly on the inverted buckets, but has also... service is what caused the traps to fail closed. The last set of traps tested was the Armstrong 1013LV stainless steel inverted buckets. The capacity of these units required that for each coil two traps in parallel would be required. The traps do...

Feldman, A. L.

1981-01-01T23:59:59.000Z

207

An ion trap built with photonic crystal fibre technology  

E-Print Network (OSTI)

We demonstrate a surface-electrode ion trap fabricated using techniques transferred from the manufacture of photonic-crystal fibres. This provides a relatively straightforward route for realizing traps with an electrode structure on the 100 micron scale with high optical access. We demonstrate the basic functionality of the trap by cooling a single ion to the quantum ground state, allowing us to measure a heating rate from the ground state of 787(24) quanta/s. Variation of the fabrication procedure used here may provide access to traps in this geometry with trap scales between 100 um and 10 um.

Lindenfelser, F; Kienzler, D; Bykov, D; Uebel, P; Schmidt, M A; Russell, P St J; Home, J P

2015-01-01T23:59:59.000Z

208

Landau damping and the onset of particle trapping in quantum plasmas  

SciTech Connect

Using analytical theory and simulations, we assess the impact of quantum effects on non-linear wave-particle interactions in quantum plasmas. We more specifically focus on the resonant interaction between Langmuir waves and electrons, which, in classical plasmas, lead to particle trapping. Two regimes are identified depending on the difference between the time scale of oscillation t{sub B}(k)=?(m/eEk) of a trapped electron and the quantum time scale t{sub q}(k)=2m/?k{sup 2} related to recoil effect, where E and k are the wave amplitude and wave vector. In the classical-like regime, t{sub B}(k)?trapped in the wave troughs and greatly affect the evolution of the system long before the wave has had time to Landau damp by a large amount according to linear theory. In the quantum regime, t{sub B}(k)?>?t{sub q}(k), particle trapping is hampered by the finite recoil imparted to resonant electrons in their interactions with plasmons.

Daligault, Jérôme [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-04-15T23:59:59.000Z

209

Use of Bullet Traps and Steel Targets  

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

USE OF BULLET TRAPS AND USE OF BULLET TRAPS AND STEEL TARGETS U.S. DEPARTMENT OF ENERGY Office of Health, Safety and Security AVAILABLE ONLINE AT: INITIATED BY: http://www.hss.energy.gov Office of Health, Safety and Security Notices This document is intended for the exclusive use of elements of the Department of Energy (DOE), to include the National Nuclear Security Administration, their contractors, and other government agencies/individuals authorized to use DOE facilities. DOE disclaims any and all liability for personal injury or property damage due to use of this document in any context by any organization, group, or individual, other than during official government activities. Local DOE management is responsible for the proper execution of firearms-related programs for

210

Nonperturbative Coherent Population Trapping: An Analytic Model  

Science Journals Connector (OSTI)

Coherent population trapping is shown to occur in a driven symmetric double-well potential in the strong-field regime. The system parameters have been chosen to reproduce the 0-?3+ transition of the inversion mode of the ammonia molecule. For a molecule initially prepared in its lower doublet we find that, under certain circumstances, the 3+ level remains unpopulated, and this occurs in spite of the fact that the laser field is resonant with the 0-?3+ transition and intense enough so as to strongly mix the 0+ and 0- ground states. This counterintuitive result constitutes a coherent population trapping phenomenon of nonperturbative origin which cannot be accounted for with the usual models.

V. Delgado and J. M. Gomez Llorente

2002-01-23T23:59:59.000Z

211

Shortcuts to adiabaticity for trapped ultracold gases  

E-Print Network (OSTI)

We study, experimentally and theoretically, the controlled transfer of harmonically trapped ultracold gases between different quantum states. In particular we experimentally demonstrate a fast decompression and displacement of both a non-interacting gas and an interacting Bose-Einstein condensate which are initially at equilibrium. The decompression parameters are engineered such that the final state is identical to that obtained after a perfectly adiabatic transformation despite the fact that the fast decompression is performed in the strongly non-adiabatic regime. During the transfer the atomic sample goes through strongly out-of-equilibrium states while the external confinement is modified until the system reaches the desired stationary state. The scheme is theoretically based on the invariants of motion and scaling equations techniques and can be generalized to decompression trajectories including an arbitrary deformation of the trap. It is also directly applicable to arbitrary initial non-equilibrium sta...

Schaff, Jean-François; Labeyrie, Guillaume; Vignolo, Patrizia

2011-01-01T23:59:59.000Z

212

Shortcuts to adiabaticity for trapped ultracold gases  

E-Print Network (OSTI)

We study, experimentally and theoretically, the controlled transfer of harmonically trapped ultracold gases between different quantum states. In particular we experimentally demonstrate a fast decompression and displacement of both a non-interacting gas and an interacting Bose-Einstein condensate which are initially at equilibrium. The decompression parameters are engineered such that the final state is identical to that obtained after a perfectly adiabatic transformation despite the fact that the fast decompression is performed in the strongly non-adiabatic regime. During the transfer the atomic sample goes through strongly out-of-equilibrium states while the external confinement is modified until the system reaches the desired stationary state. The scheme is theoretically based on the invariants of motion and scaling equations techniques and can be generalized to decompression trajectories including an arbitrary deformation of the trap. It is also directly applicable to arbitrary initial non-equilibrium states.

Jean-François Schaff; Pablo Capuzzi; Guillaume Labeyrie; Patrizia Vignolo

2011-05-11T23:59:59.000Z

213

Magneto-Optical Trapping of Holmium Atoms  

E-Print Network (OSTI)

We demonstrate sub-Doppler laser cooling and magneto-optical trapping of the rare earth element Holmium. Atoms are loaded from an atomic beam source and captured in six-beam $\\sigma_+ - \\sigma_-$ molasses using a strong $J=15/2 \\leftrightarrow J=17/2$ cycling transition at $\\lambda=410.5 \\rm nm$. Due to the small difference in hyperfine splittings and Land\\'e $g$-factors in the lower and upper levels of the cooling transition the MOT is self-repumped without additional repump light, and deep sub-Doppler cooling is achieved with the magnetic trap turned on. We measure the leakage out of the cycling transition to metastable states and find a branching ratio $\\sim 10^{-5}$ which is adequate for state resolved measurements on hyperfine encoded qubits.

J. Miao; J. Hostetter; G. Stratis; M. Saffman

2014-03-24T23:59:59.000Z

214

Trapped ghosts: a new class of wormholes  

E-Print Network (OSTI)

We construct examples of static, spherically symmetric wormhole solutions in general relativity with a minimally coupled scalar field $\\phi$ whose kinetic energy is negative in a restricted region of space near the throat (of arbitrary size) and positive far from it. Thus in such configurations a "ghost" is trapped in the strong-field region, which may in principle explain why no ghosts are observed under usual conditions. Some properties of general wormhole models with the $\\phi$ field are revealed: it is shown that (i) trapped-ghost wormholes are only possible with nonzero potentials $V(\\phi)$; (ii) in twice asymptotically flat wormholes, a nontrivial potential $V(\\phi)$ has an alternate sign, and (iii) a twice asymptotically flat wormhole which is mirror-symmetric with respect to its throat has necessarily a zero Schwarzschild mass at both asymptotics.

Kirill A. Bronnikov; Sergey V. Sushkov

2010-01-20T23:59:59.000Z

215

Trapped ghosts: a new class of wormholes  

E-Print Network (OSTI)

We construct examples of static, spherically symmetric wormhole solutions in general relativity with a minimally coupled scalar field $\\phi$ whose kinetic energy is negative in a restricted region of space near the throat (of arbitrary size) and positive far from it. Thus in such configurations a "ghost" is trapped in the strong-field region, which may in principle explain why no ghosts are observed under usual conditions. Some properties of general wormhole models with the $\\phi$ field are revealed: it is shown that (i) trapped-ghost wormholes are only possible with nonzero potentials $V(\\phi)$; (ii) in twice asymptotically flat wormholes, a nontrivial potential $V(\\phi)$ has an alternate sign, and (iii) a twice asymptotically flat wormhole which is mirror-symmetric with respect to its throat has necessarily a zero Schwarzschild mass at both asymptotics.

Bronnikov, Kirill A

2010-01-01T23:59:59.000Z

216

Ion temperature gradient driven turbulence with strong trapped ion resonance  

SciTech Connect

A theory to describe basic characterization of ion temperature gradient driven turbulence with strong trapped ion resonance is presented. The role of trapped ion granulations, clusters of trapped ions correlated by precession resonance, is the focus. Microscopically, the presence of trapped ion granulations leads to a sharp (logarithmic) divergence of two point phase space density correlation at small scales. Macroscopically, trapped ion granulations excite potential fluctuations that do not satisfy dispersion relation and so broaden frequency spectrum. The line width from emission due only to trapped ion granulations is calculated. The result shows that the line width depends on ion free energy and electron dissipation, which implies that non-adiabatic electrons are essential to recover non-trivial dynamics of trapped ion granulations. Relevant testable predictions are summarized.

Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Itoh, S.-I. [Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Diamond, P. H. [CASS and CMTFO, University of California at San Diego, La Jolla, California 92093 (United States); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Itoh, K. [National Institute for Fusion Science, Gifu (Japan); Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Lesur, M. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan)

2014-10-15T23:59:59.000Z

217

Subwavelength edge detection through trapped resonances in waveguides  

E-Print Network (OSTI)

Lenses that can collect the perfect image of an object must restore propagative and evanescent waves. However, for efficient information transfer, e.g., in compressed sensing, it is often desirable to detect only the fast spatial variations of the wave field (carried by evanescent waves), as the one created by edges or small details. Image processing edge detection algorithms perform such operation but they add time and complexity to the imaging process. Here, we present a new subwavelength approach that generates an image of only those components of the acoustic field that are equal to or smaller than the operating wavelength. The proposed technique converts evanescent waves into propagative waves exciting trapped resonances in a waveguide, and it uses periodicity to attenuate the propagative components. This approach achieves resolutions about an order of magnitude smaller than the operating wavelength and makes it possible to visualize independently edges aligned along different directions.

Molerón, Miguel

2015-01-01T23:59:59.000Z

218

Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames  

SciTech Connect

We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (?g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in ?g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in ?g flames, which reduces the time to gel for nanoparticles by ?10{sup 6}?s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.

Chakrabarty, Rajan K., E-mail: rajan.chakrabarty@gmail.com [Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130 (United States); Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Novosselov, Igor V. [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Enertechnix Inc., Maple Valley, Washington 98068 (United States); Beres, Nicholas D.; Moosmüller, Hans [Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Sorensen, Christopher M. [Condensed Matter Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States); Stipe, Christopher B. [TSI Incorporated, 500 Cardigan Rd, Shoreview, Minnesota 55126 (United States)

2014-06-16T23:59:59.000Z

219

Nuclear spin cooling using Overhauser field selective coherent population trapping  

E-Print Network (OSTI)

Hyperfine interactions with a nuclear spin environment fundamentally limit the coherence properties of confined electron spins in the solid-state. Here, we show that a quantum interference effect in optical absorption from two electronic spin states of a solid-state emitter can be used to prepare the surrounding environment of nuclear spins in well-defined states, thereby suppressing electronic spin dephasing. The evolution of the coupled electron-nuclei system into a coherent population trapping state by optical excitation induced nuclear spin diffusion can be described in terms of Levy flights, in close analogy with sub-recoil laser cooling of atoms. The large difference in electronic and nuclear time scales simultaneously allow for a measurement of the magnetic field produced by nuclear spins, making it possible to turn the lasers that cause the anomalous spin diffusion process off when the strength of the resonance fluorescence reveals that the nuclear spins are in the desired narrow state.

Mena Issler; Eric Kessler; Geza Giedke; Susanne Yelin; Ignacio Cirac; Mikhail Lukin; Atac Imamoglu

2010-08-20T23:59:59.000Z

220

An optically trapped mirror for reaching the standard quantum limit  

E-Print Network (OSTI)

The preparation of a mechanical oscillator driven by quantum back-action is a fundamental requirement to reach the standard quantum limit (SQL) for force measurement, in optomechanical systems. However, thermal fluctuating force generally dominates a disturbance on the oscillator. In the macroscopic scale, an optical linear cavity including a suspended mirror has been used for the weak force measurement, such as gravitational-wave detectors. This configuration has the advantages of reducing the dissipation of the pendulum (i.e., suspension thermal noise) due to a gravitational dilution by using a thin wire, and of increasing the circulating laser power. However, the use of the thin wire is weak for an optical torsional anti-spring effect in the cavity, due to the low mechanical restoring force of the wire. Thus, there is the trade-off between the stability of the system and the sensitivity. Here, we describe using a triangular optical cavity to overcome this limitation for reaching the SQL. The triangular cavity can provide a sensitive and stable system, because it can optically trap the mirror's motion of the yaw, through an optical positive torsional spring effect. To show this, we demonstrate a measurement of the torsional spring effect caused by radiation pressure forces.

Nobuyuki Matsumoto; Yuta Michimura; Yoichi Aso; Kimio Tsubono

2014-05-19T23:59:59.000Z

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


221

Isotopic abundance in atom trap trace analysis  

DOE Patents (OSTI)

A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

Lu, Zheng-Tian; Hu, Shiu-Ming; Jiang, Wei; Mueller, Peter

2014-03-18T23:59:59.000Z

222

Gas turbine engines with particle traps  

DOE Patents (OSTI)

A gas turbine engine (10) incorporates a particle trap (46) that forms an entrapment region (73) in a plenum (24) which extends from within the combustor (18) to the inlet (32) of a radial-inflow turbine (52, 54). The engine (10) is thereby adapted to entrap particles that originate downstream from the compressor (14) and are otherwise propelled by combustion gas (22) into the turbine (52, 54). Carbonaceous particles that are dislodged from the inner wall (50) of the combustor (18) are incinerated within the entrapment region (73) during operation of the engine (10).

Boyd, Gary L. (Tempe, AZ); Sumner, D. Warren (Phoenix, AZ); Sheoran, Yogendra (Scottsdale, AZ); Judd, Z. Daniel (Phoenix, AZ)

1992-01-01T23:59:59.000Z

223

Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil  

SciTech Connect

Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

DeAngelis, Kristen; Allgaier, Martin; Chavarria, Yaucin; Fortney, Julian; Hugenholtz, Phillip; Simmons, Blake; Sublette, Kerry; Silver, Whendee; Hazen, Terry

2011-07-14T23:59:59.000Z

224

Characterization of trapped lignin-degrading microbes in tropical forest soil  

SciTech Connect

Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

DeAngelis, K.M.; Allgaier, M.; Chavarria, Y.; Fortney, J.L.; Hugenholz, P.; Simmons, B.; Sublette, K.; Silver, W.L.; Hazen, T.C.

2011-03-01T23:59:59.000Z

225

Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil  

SciTech Connect

Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

DeAngelis, Kristen M.; Allgaier, Martin; Chavarria, Yaucin; Fortney, Julian L.; Hugenholtz, Philip; Simmons, Blake A.; Sublette, Kerry; Silver, Whendee; Hazen, Terry C.

2011-04-29T23:59:59.000Z

226

New nano trap protects environment | Argonne National Laboratory  

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

New nano trap protects environment New nano trap protects environment By Tona Kunz * October 31, 2012 Tweet EmailPrint This story was originally published in volume 10, number 5 of Innovation magazine. A new type of nanoscale molecular trap makes it possible for industry to store large amounts of hydrogen in small fuel cells or capture, compact and remove volatile radioactive gas from spent nuclear fuel in an affordable, easily commercialized way. The ability to adjust the size of the trap openings to select for specific molecules or to alter how molecules are released at industrially accessible pressures makes the trap uniquely versatile. The trap is constructed of commercially available material and made possible through collaborative work at Argonne and Sandia national laboratories. "This introduces a new class of materials to nuclear waste remediation,"

227

Emittance Measurements of Trapped Electrons from a Plasma Wakefield Accelerator  

SciTech Connect

Recent electron beam driven plasma wakefield accelerator experiments carried out at SLAC showed trapping of plasma electrons. These trapped electrons appeared on an energy spectrometer with smaller transverse size than the beam driving the wake. A connection is made between transverse size and emittance; due to the spectrometer's resolution, this connection allows for placing an upper limit on the trapped electron emittance. The upper limit for the lowest normalized emittance measured in the experiment is 1 mm {center_dot} mrad.

Kirby, N.; Berry, M.; Blumenfeld, I.; Decker, F.-J.; Hogan, M.J.; Ischebeck, R.; Iverson, R.; Siemann, R.; Walz, D.; /SLAC; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

2007-06-28T23:59:59.000Z

228

Decoherence in a single trapped ion due to engineered reservoir  

E-Print Network (OSTI)

The decoherence in trapped ion induced by coupling the ion to the engineered reservoir is studied in this paper. The engineered reservoir is simulated by random variations in the trap frequency, and the trapped ion is treated as a two-level system driven by a far off-resonant plane wave laser field. The dependence of the decoherence rate on the amplitude of the superposition state is given.

X. X. Yi; D. L. Zhou; C. P. Sun

2000-04-18T23:59:59.000Z

229

Gas insulated transmission line having tapered particle trapping ring  

DOE Patents (OSTI)

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

Cookson, Alan H. (Pittsburgh, PA)

1982-01-01T23:59:59.000Z

230

Fundamental Limit of Nanophotonic Light-Trapping in Solar Cells  

Science Journals Connector (OSTI)

We use a rigorous electromagnetic approach to develop a light-trapping theory, which reveals that the conventional limit 4n2can be substantially surpassed in nanophotonic...

Yu, Zongfu; Raman, Aaswath; Fan, Shanhui

231

Requirements-Driven Diesel Catalyzed Particulate Trap Design...  

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

Driven Diesel Catalyzed Particulate Trap (DCPT) Design and Optimization Tom Harris, Donna McConnell and Danan Dou Delphi Catalyst Tulsa, Oklahoma 2 Euro 45 Light Duty...

232

Dielectric nanostructures for broadband light trapping in organic solar cells  

Science Journals Connector (OSTI)

We investigate broadband light trapping using only dielectric components to improve organic solar cell efficiency. We show that substantial absorption and photocurrent enhancement is...

Raman, Aaswath; Yu, Zongfu; Fan, Shanhui

233

Variational calculation of the trapping rate in thermal barriers  

SciTech Connect

A variational calculation of the trapping rate and trapped ion density in thermal barriers is presented. The effects of diffusion in energy as well as pitch angle scattering are retained. The variational formulation uses the actual trapped-passing boundary in velocity space. The boundary condition is that the trapped ion distribution function matches the passing ion distribution function, which is taken to be a Maxwellian, on the boundary. The results compare well with two-dimensional Fokker-Planck code calculations by Futch and LoDestro.

Li, X.Z.; Emmert, G.A.

1982-10-01T23:59:59.000Z

234

Location Of Hole And Electron Traps On Nanocrystalline Anatase...  

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

to two overlapping distributions: hole trap emission associated with oxygen vacancies on (101) exposed surfaces, which peaks in the green, and a broader emission...

235

Characterisation of Dust Particles Trapped in Silica Aerogels.  

E-Print Network (OSTI)

?? This thesis involves the study of dust particles trapped in silica aerogel for fusion dust diagnostics purpose. The low velocity impact experiments are done… (more)

Liu, Bing

2011-01-01T23:59:59.000Z

236

Storage of Ultracold Neutrons in the Magneto-Gravitational Trap of the UCN Experiment  

SciTech Connect

The UCN experiment is designed to measure the lifetime n of the free neutron by trapping ultracold neutrons (UCN) in a magneto-gravitational trap. An asymmetric bowl-shaped NdFeB magnet Halbach array confines low-field-seeking UCN within the apparatus, and a set of electromagnetic coils in a toroidal geometry provides a background holding field to eliminate depolarization-induced UCN loss caused by magnetic field nodes. We present a measurement of the storage time store of the trap by storing UCN for various times and counting the survivors. The data are consistent with a single exponential decay, and we find store = 860 19 s, within 1 of current global averages for n. The storage time with the holding field deactivated is found to be store = 470 160 s; this decreased storage time is due to the loss of UCN, which undergo Majorana spin flips while being stored. We discuss plans to increase the statistical sensitivity of the measurement and investigate potential systematic effects.

Salvat, D. J. [Indiana University] [Indiana University; Adamek, E. R. [Indiana University] [Indiana University; Barlow, D. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Bowman, James D [ORNL] [ORNL; Broussard, L. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Callahan, N. B. [Indiana University] [Indiana University; Clayton, S. M. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Cude-Woods, C. [Indiana University] [Indiana University; Currie, S. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Dees, E. B. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh; Fox, W. [Indiana University] [Indiana University; Geltenbort, P. [Inst Max Von Laue Paul Langevin, Grenoble, France] [Inst Max Von Laue Paul Langevin, Grenoble, France; Hickerson, K. P. [University of California, Los Angeles] [University of California, Los Angeles; Holley, A. T. [Indiana University] [Indiana University; Liu, C.-Y. [Indiana University] [Indiana University; Makela, M. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Medina, J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Morley, D. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Morris, C. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Penttila, Seppo I [ORNL] [ORNL; Ramsey, J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Saunders, A. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Seestrom, S. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Sharapov, E. I. [Joint Institute for Nuclear Research, Dubna, Russia] [Joint Institute for Nuclear Research, Dubna, Russia; Sjue, S. K. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Slaughter, B. A. [Indiana University] [Indiana University; Vanderwerp, J. [Indiana University] [Indiana University; VornDick, B. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh; Walstrom, P. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Wang, Z. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Womack, T. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Young, A. R. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh

2014-01-01T23:59:59.000Z

237

Parallel heat flux and flow acceleration in open field line plasmas with magnetic trapping  

SciTech Connect

The magnetic field strength modulation in a tokamak scrape-off layer (SOL) provides both flux expansion next to the divertor plates and magnetic trapping in a large portion of the SOL. Previously, we have focused on a flux expander with long mean-free-path, motivated by the high temperature and low density edge anticipated for an absorbing boundary enabled by liquid lithium surfaces. Here, the effects of magnetic trapping and a marginal collisionality on parallel heat flux and parallel flow acceleration are examined. The various transport mechanisms are captured by kinetic simulations in a simple but representative mirror-expander geometry. The observed parallel flow acceleration is interpreted and elucidated with a modified Chew-Goldberger-Low model that retains temperature anisotropy and finite collisionality.

Guo, Zehua; Tang, Xian-Zhu; McDevitt, Chris [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-10-15T23:59:59.000Z

238

Time-resolved plasma measurements in Ge-doped silica exposed to infrared femtosecond laser  

SciTech Connect

Using a time-resolved interferometric technique, we study the laser-induced carrier-trapping dynamics in SiO{sub 2} and Ge-doped SiO{sub 2}. The fast trapping of electrons in the band gap is associated with the formation of self-trapped excitons (STE). The STE trapping is doping dependent in SiO{sub 2}. The mean trapping time of electrons excited in the conduction band was found to be significantly lower in Ge-doped silica (75 {+-} 5 fs) when compared to pure silica (155 {+-} 5 fs). At our concentration level, this indicates that the plasma properties are determined by the presence of easily ionizable states such as the presence of Ge atoms in the glass network. Therefore, we suggest that in Ge-doped silica there exist an additional trapping pathway that leads to a significantly faster excitons trapping and a higher plasma density when compared to undoped silica.

Lancry, M.; Poumellec, B. [LPCES/ICMMO, UMR CNRS-UPS 8182, Universite Paris Sud 11, Batiment 410, 91405 Orsay (France); Groothoff, N.; Canning, J. [Interdisciplinary Photonics Laboratories, School of Chemistry, University of Sydney, 206 NIC, ATP, Eveleigh, NSW, 1340 (Australia); Guizard, S.; Fedorov, N. [Laboratoire des Solides Irradies/CEA IRAMIS, Ecole Polytechnique, Palaiseau (France)

2011-12-15T23:59:59.000Z

239

Measurement of low-energy Na^+ -- Na total collision rate in an ion--neutral hybrid trap  

E-Print Network (OSTI)

We present measurements of the total elastic and resonant charge-exchange ion-atom collision rate coefficient $k_\\mathrm{ia}$ of cold sodium (\\ce{Na}) with optically-dark low energy \\ce{Na+} ions in a hybrid ion-neutral trap. To determine $k_\\mathrm{ia}$, we measured the trap loading and loss from both a \\ce{Na} magneto-optical trap (MOT) and a linear radio frequency quadrupole Paul trap. We found the total rate coefficient to be $7.4 \\pm 1.9 \\times 10^{-8}$ cm$^3$/s for the type I \\ce{Na} MOT immersed within an $\\approx 140$ K ion cloud and $1.10 \\pm 0.25 \\times 10^{-7}$ cm$^3$/s for the type II \\ce{Na} MOT within an $\\approx 1070$ K ion cloud. Our measurements show excellent agreement with previously reported theoretical fully quantal \\textit{ab initio} calculations. In the process of determining the total rate coefficient, we demonstrate that a MOT can be used to probe an optically dark ion cloud's spatial distribution within a hybrid trap.

Goodman, D S; Kwolek, J M; Blümel, R; Narducci, F A; Smith, W W

2014-01-01T23:59:59.000Z

240

A Microscale Gas Trapping Investigation Markus Buchgraber, Anthony R. Kovscek  

E-Print Network (OSTI)

A Microscale Gas Trapping Investigation Markus Buchgraber, Anthony R. Kovscek Department of Energy unit Residual Trapping Sgi Sg,max krg krg Sgt(Soi) Sgt,max Gas Saturation Gas relative Land Model * * ** 1 )( gi gi gigt CS S SS + = Sgf Sg Sgt,max kd rg Sg Gas Saturation

Stanford University

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Biodiversity Conservation and Poverty Traps December 2, 2009  

E-Print Network (OSTI)

Biodiversity Conservation and Poverty Traps December 2, 2009 Co-organizers Alex Travis and Chris biodiversity conservation and poverty traps. Multiple participants observed that Cornell has relatively large. A good deal of discussion concerned the emphasis on biodiversity conservation as opposed to broader

Angenent, Lars T.

242

Pinch Effect for Trapped Particles in a Tokamak  

Science Journals Connector (OSTI)

Conservation of canonical angular momentum is shown to require that all trapped particles drift towards the magnetic axis with velocity cE?B? (E? is the toroidal electric field; B? the poloidal magnetic field). This property, plus an amplification process for the number of trapped particles, will explain the relaxation oscillations which occur for q3.

A. A. Ware

1970-07-06T23:59:59.000Z

243

Novel Dipole Trapped Spheromak Configuration M. R. Brown,1,  

E-Print Network (OSTI)

Novel Dipole Trapped Spheromak Configuration M. R. Brown,1, * C. D. Cothran,1 J. Fung,1 M. J. Schaffer,2 and E. Belova3 We report the observation and characterization of a spheromak formed in the Swarthmore Spheromak Experiment (SSX) and trapped in a simple dipole magnetic field. The spheromak is studied

Brown, Michael R.

244

Successful Implementation of a Sustainable Trap Management Program.  

E-Print Network (OSTI)

significant cost penalty in delaying implementation of a program to manage the steam trap population. Plants typically embark on a trap management initiative by focusing on a survey, but may not maximize returns because they fail to execute or sustain possible...

Walter, J.

2013-01-01T23:59:59.000Z

245

Steam Traps-The Oft Forgotten Energy Conservation Treasure  

E-Print Network (OSTI)

In these days of high technology, the steam trap is often treated as a commodity item, forgotten by many and respected by a relative few. Yet, in many facilities, widespread undetected failure of steam traps has wasted 5-15% of a plant's total steam...

Pychewicz, F. S.

246

Solar cell efficiency enhancement via light trapping in printable resonant  

E-Print Network (OSTI)

Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere for addressing the key challenge of light trapping in thin-film solar cells. We experimentally and theoretically the absorber, junction, and passivation layers. Recently, a number of innovative solar cell light

Atwater, Harry

247

Dielectric nanostructures for broadband light trapping in organic solar cells  

E-Print Network (OSTI)

Dielectric nanostructures for broadband light trapping in organic solar cells Aaswath Raman, Zongfu light trapping configuration for thin-film solar cells," Appl. Phys. Lett. 91, 243501 (2007). 8. M@stanford.edu Abstract: Organic bulk heterojunction solar cells are a promising candidate for low-cost next

Fan, Shanhui

248

Solar cell efficiency enhancement via light trapping in printable resonant  

E-Print Network (OSTI)

Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere for addressing the key challenge of light trapping in thin-film solar cells. We experimentally and theoretically, photovoltaics, resonant dielectric structures, solar cells * Corresponding author: e-mail jgrandid

Grandidier, Jonathan

249

Sympathetic cooling of trapped ions with resonant laser radiation  

SciTech Connect

We propose a novel model to describe dynamic properties of ions that are cooled by collisions with other laser-cooled ions in a quadrupole rf trap. The limit temperature of the sympathetic Cooling is estimated as functions of the trap and laser parameters, and the mass of the ions.

Shimizu, T.; Oshima, Y.; Moriwaki, Y.; Tachikawa, M. [Univ. of Tokyo (Japan)

1994-12-31T23:59:59.000Z

250

Particle-optical self-trapping  

SciTech Connect

The formation of a self-guided beam pattern via optical trapping in a suspension of Rayleigh scatterers is studied. An analytic self-guided solution is presented that is valid for low intensities. A numerical solution of the coupled diffusion and optical-wave equations is presented, which shows an evolution toward a steady state that is independent of the initial optical beam shape. At higher intensities, the numerical solution shows the influence of higher-order nonlinearities, which lead to instability. We define a critical optical intensity, in terms of the particle size, refractive index contrast, and thermal energy, that characterizes the onset of higher-order effects. Instability is found that is consistent with past parametric studies of solitons.

Gordon, R.; Blakely, J. T.; Sinton, D. [Department of Electrical and Computer Engineering, University of Victoria, Victoria, British Columbia, Canada V8P 5C2 (Canada); Department of Mechanical Engineering, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2 (Canada)

2007-05-15T23:59:59.000Z

251

Penning trap mass measurements on nobelium isotopes  

SciTech Connect

The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt allows accurate mass measurements of radionuclides, produced in fusion-evaporation reactions and separated by the velocity filter SHIP from the primary beam. Recently, the masses of the three nobelium isotopes {sup 252-254}No were determined. These are the first direct mass measurements of transuranium elements, which provide new anchor points in this region. The heavy nuclides were produced in cold-fusion reactions by irradiating a PbS target with a {sup 48}Ca beam, resulting in production rates of the nuclei of interest of about one atom per second. In combination with data from decay spectroscopy our results are used to perform a new atomic-mass evaluation in this region.

Dworschak, M.; Block, M.; Ackermann, D.; Herfurth, F.; Hessberger, F. P.; Hofmann, S.; Vorobyev, G. K. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Audi, G. [CSNSM-IN2P3-CNRS, F-91405 Orsay-Campus (France); Blaum, K. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Ruprecht-Karls-Universitaet, D-69120 Heidelberg (Germany); Droese, C.; Marx, G.; Schweikhard, L. [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, D-17487 Greifswald (Germany); Eliseev, S.; Ketter, J. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Fleckenstein, T. [Justus-Liebig-Universitaet Giessen, D-35390 Giessen (Germany); Haettner, E.; Plass, W. R.; Scheidenberger, C. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Justus-Liebig-Universitaet Giessen, D-35390 Giessen (Germany); Ketelaer, J. [Johannes Gutenberg-Universitaet, Institut fuer Physik, D-55099 Mainz (Germany); Kluge, H.-J. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Ruprecht-Karls-Universitaet, D-69120 Heidelberg (Germany)

2010-06-15T23:59:59.000Z

252

Contaminant trap for gas-insulated apparatus  

DOE Patents (OSTI)

A contaminant trap for a gas-insulated electrical conductor is provided. A resinous dielectric body such as Kel-F wax, grease or other sticky polymeric or oligomeric compound is disposed on the inside wall of the outer housing for the conductor. The resinous body is sufficiently sticky at ambient temperatures to immobilize contaminant particles in the insulating gas on the exposed surfaces thereof. An electric resistance heating element is disposed in the resinous body to selectively raise the temperature of the resinous body to a molten state so that the contaminant particles collected on the surface of the body sink into the body so that the surface of the resinous body is renewed to a particle-less condition and, when cooled, returns to a sticky collecting surface.

Adcock, James L. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

1984-01-01T23:59:59.000Z

253

Electrostatic particle trap for ion beam sputter deposition  

DOE Patents (OSTI)

A method and apparatus for the interception and trapping of or reflection of charged particulate matter generated in ion beam sputter deposition. The apparatus involves an electrostatic particle trap which generates electrostatic fields in the vicinity of the substrate on which target material is being deposited. The electrostatic particle trap consists of an array of electrode surfaces, each maintained at an electrostatic potential, and with their surfaces parallel or perpendicular to the surface of the substrate. The method involves interception and trapping of or reflection of charged particles achieved by generating electrostatic fields in the vicinity of the substrate, and configuring the fields to force the charged particulate material away from the substrate. The electrostatic charged particle trap enables prevention of charged particles from being deposited on the substrate thereby enabling the deposition of extremely low defect density films, such as required for reflective masks of an extreme ultraviolet lithography (EUVL) system.

Vernon, Stephen P. (Pleasanton, CA); Burkhart, Scott C. (Livermore, CA)

2002-01-01T23:59:59.000Z

254

Ion-trap electrode preparation with Ne$^+$ bombardment  

E-Print Network (OSTI)

We describe an ex-situ surface-cleaning procedure that is shown to reduce motional heating from ion-trap electrodes. This precleaning treatment, to be implemented immediately before the final assembly and vacuum processing of ion traps, removes surface contaminants remaining after the electrode-fabrication process. We incorporate a multi-angle ion-bombardment treatment intended to clean the electrode surfaces and interelectrode gaps of microfabricated traps. This procedure helps to minimize redeposition in the gaps between electrodes that can cause electrical shorts. We report heating rates in a stylus-type ion trap prepared in this way that are lower by one order of magnitude compared to a similar untreated stylus-type trap using the same experimental setup.

McKay, K S; Colombe, Y; Jördens, R; Wilson, A C; Slichter, D H; Allcock, D T C; Leibfried, D; Wineland, D J; Pappas, D P

2014-01-01T23:59:59.000Z

255

Ion-trap electrode preparation with Ne$^+$ bombardment  

E-Print Network (OSTI)

We describe an ex-situ surface-cleaning procedure that is shown to reduce motional heating from ion-trap electrodes. This precleaning treatment, to be implemented immediately before the final assembly and vacuum processing of ion traps, removes surface contaminants remaining after the electrode-fabrication process. We incorporate a multi-angle ion-bombardment treatment intended to clean the electrode surfaces and interelectrode gaps of microfabricated traps. This procedure helps to minimize redeposition in the gaps between electrodes that can cause electrical shorts. We report heating rates in a stylus-type ion trap prepared in this way that are lower by one order of magnitude compared to a similar untreated stylus-type trap using the same experimental setup.

K. S. McKay; D. A. Hite; Y. Colombe; R. Jördens; A. C. Wilson; D. H. Slichter; D. T. C. Allcock; D. Leibfried; D. J. Wineland; D. P. Pappas

2014-06-06T23:59:59.000Z

256

Demonstration of a Scalable, Multiplexed Ion Trap for Quantum Information Processing  

E-Print Network (OSTI)

A scalable, multiplexed ion trap for quantum information processing is fabricated and tested. The trap design and fabrication process are optimized for scalability to small trap size and large numbers of interconnected ...

Leibrandt, David R.

257

Measurements of electric field noise and light-induced charging in cryogenic surface electrode ion traps  

E-Print Network (OSTI)

Ion traps provide an excellent tool for controlling and observing the state of a single trapped ion. For this reason, ion traps have been proposed as a possible system for large-scale quantum computation. However, many ...

Lachenmyer, Nathan S. (Nathan Scott)

2010-01-01T23:59:59.000Z

258

Circulating Optical Particle Trapping through the Integration of Fiber Optics and Microfluidics  

Science Journals Connector (OSTI)

A dual-fiber optic trap is integrated with microfluidics, and stable circulatory particle trapping is observed. The unique circulating and flow-dependant nature of the trap enables...

Blakely, J Thomas; Gordon, Reuven; Sinton, David

259

Dynamic Distance Disorder in Proteins Is Caused by Trapping Guobin Luo,, Ioan Andricioaei,, X. Sunney Xie,*, and Martin Karplus*,,|  

E-Print Network (OSTI)

Dynamic Distance Disorder in Proteins Is Caused by Trapping Guobin Luo,, Ioan Andricioaei,,§ XVed: December 23, 2005; In Final Form: March 8, 2006 Dynamic disorder in proteins, as demonstrated by variations temperatures on femtosecond to nanosecond time scales. This indicates that the calculated dynamic disorder

Xie, Xiaoliang Sunney

260

Properties of Trapped Electron Bunches in a Plasma Wakefield Accelerator  

SciTech Connect

Plasma-based accelerators use the propagation of a drive bunch through plasma to create large electric fields. Recent plasma wakefield accelerator (PWFA) experiments, carried out at the Stanford Linear Accelerator Center (SLAC), successfully doubled the energy for some of the 42 GeV drive bunch electrons in less than a meter; this feat would have required 3 km in the SLAC linac. This dissertation covers one phenomenon associated with the PWFA, electron trapping. Recently it was shown that PWFAs, operated in the nonlinear bubble regime, can trap electrons that are released by ionization inside the plasma wake and accelerate them to high energies. These trapped electrons occupy and can degrade the accelerating portion of the plasma wake, so it is important to understand their origins and how to remove them. Here, the onset of electron trapping is connected to the drive bunch properties. Additionally, the trapped electron bunches are observed with normalized transverse emittance divided by peak current, {epsilon}{sub N,x}/I{sub t}, below the level of 0.2 {micro}m/kA. A theoretical model of the trapped electron emittance, developed here, indicates that the emittance scales inversely with the square root of the plasma density in the non-linear 'bubble' regime of the PWFA. This model and simulations indicate that the observed values of {epsilon}{sub N,x}/I{sub t} result from multi-GeV trapped electron bunches with emittances of a few {micro}m and multi-kA peak currents. These properties make the trapped electrons a possible particle source for next generation light sources. This dissertation is organized as follows. The first chapter is an overview of the PWFA, which includes a review of the accelerating and focusing fields and a survey of the remaining issues for a plasma-based particle collider. Then, the second chapter examines the physics of electron trapping in the PWFA. The third chapter uses theory and simulations to analyze the properties of the trapped electron bunches. Chapters four and five present the experimental diagnostics and measurements for the trapped electrons. Next, the sixth chapter introduces suggestions for future trapped electron experiments. Then, Chapter seven contains the conclusions. In addition, there is an appendix chapter that covers a topic which is extraneous to electron trapping, but relevant to the PWFA. This chapter explores the feasibility of one idea for the production of a hollow channel plasma, which if produced could solve some of the remaining issues for a plasma-based collider.

Kirby, Neil; /SLAC

2009-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Advanced Light-Trapping in Thin-Film Silicon Solar Cells  

Science Journals Connector (OSTI)

Light-trapping schemes are essential for high efficiency thin-film Silicon devices. Implementation of various light-trapping/scattering elements will be discussed. An optimum textured...

Wyrsch, Nicolas

262

AMEAerospace & Mechanical  

E-Print Network (OSTI)

AMEAerospace & Mechanical Engineering #12;Aerospace and Mechanical Engineers design complex mechanical, thermal, fluidic, acousti- cal, optical, and electronic systems, with char- acteristic sizes space. Aerospace and Mechanical Engineering (AME) students conduct basic and applied research within

Wang, Hai

263

Investigating of electrons bunching in a Penning trap and accelerating process for CO2 gas mixture active medium  

E-Print Network (OSTI)

In the presence of an active medium incorporated in a Penning trap, the moving electrons can become bunched, as they get enough energy, they escape the trap forming an optical injector. These bunched electrons can enter next PASER section filled with the same active medium to be accelerated. In this paper, electron dynamics in the presence of gas mixture active medium incorporated in a penning trap is analyzed by developing an idealized 1D model. We further evaluate the energy exchange occurring as the train of electrons traversing the next PASER section. The results show that the oscillating electrons can be bunched at the resonant frequency of the active medium. The influence of the trapped time and the population inversion are analyzed, which shows that the longer the electrons are trapped, the more energy from the medium the accelerated electrons get, and with the increase of the population inversion, the decelerated electrons virtually unchanged but the accelerated electrons more than double their peak e...

Tian, Xiu-fang; Jia, Qika

2014-01-01T23:59:59.000Z

264

Coherence of a qubit stored in Zeeman levels of a single optically trapped atom  

SciTech Connect

We experimentally investigate the coherence properties of a qubit stored in the Zeeman substates of the 5{sup 2}S{sub 1/2}, F=1 hyperfine ground level of a single optically trapped {sup 87}Rb atom. Larmor precession of a single atomic spin-1 system is observed by preparing the atom in a defined initial spin state and then measuring the resulting state after a programmable period of free evolution. Additionally, by performing quantum-state tomography, maximum knowledge about the spin coherence is gathered. By using an active magnetic field stabilization and without application of a magnetic guiding field, we achieve transverse and longitudinal dephasing times of T{sub 2}{sup *}=75-150 {mu}s and T{sub 1}>0.5 ms, respectively. We derive the light-shift distribution of a single atom in the approximately harmonic potential of a dipole trap and show that the measured atomic spin coherence is limited mainly by residual position- and state-dependent effects in the optical trapping potential. The improved understanding enables longer coherence times, an important prerequisite for future applications in long-distance quantum communication and computation with atoms in optical lattices, or for a loophole-free test of Bell's inequality.

Rosenfeld, Wenjamin; Weinfurter, Harald [Fakultaet fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, D-80799 Muenchen (Germany); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Volz, Juergen; Weber, Markus [Fakultaet fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, D-80799 Muenchen (Germany)

2011-08-15T23:59:59.000Z

265

Precision lifetime measurements of a single trapped ion with ultrafast laser pulses  

SciTech Connect

We report precision measurements of the excited state lifetime of the 5p {sup 2}P{sub 1/2} and 5p {sup 2}P{sub 3/2} levels of a single trapped Cd{sup +} ion. Combining ion trap and ultrafast laser technologies, the ion is excited with picosecond laser pulses from a mode-locked laser and the distribution of arrival times of spontaneously emitted photons is recorded. The resulting lifetimes are 3.148{+-}0.011 ns and 2.647{+-}0.010 ns for {sup 2}P{sub 1/2} and {sup 2}P{sub 3/2} respectively. With a total uncertainty of under 0.4%, these are among the most precise measurements of any atomic state lifetimes to date.

Moehring, D. L.; Blinov, B. B.; Gidley, D. W.; Kohn, R. N. Jr.; Madsen, M. J.; Sanderson, T. D.; Vallery, R. S.; Monroe, C. [FOCUS Center and Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

2006-02-15T23:59:59.000Z

266

Measurement of the Neutron Lifetime by Counting Trapped Protons in a Cold Neutron Beam  

E-Print Network (OSTI)

A measurement of the neutron lifetime $\\tau_{n}$ performed by the absolute counting of in-beam neutrons and their decay protons has been completed. Protons confined in a quasi-Penning trap were accelerated onto a silicon detector held at a high potential and counted with nearly unit efficiency. The neutrons were counted by a device with an efficiency inversely proportional to neutron velocity, which cancels the dwell time of the neutron beam in the trap. The result is $\\tau_{n} = (886.6\\pm1.2{\\rm [stat]}\\pm3.2{\\rm [sys]})$ s, which is the most precise measurement of the lifetime using an in-beam method. The systematic uncertainty is dominated by neutron counting, in particular the mass of the deposit and the $^{6}$Li({\\it{n,t}}) cross section. The measurement technique and apparatus, data analysis, and investigation of systematic uncertainties are discussed in detail.

J. S. Nico; M. S. Dewey; D. M. Gilliam; F. E. Wietfeldt; X. Fei; W. M. Snow; G. L. Greene; J. Pauwels; R. Eykens; A. Lamberty; J. Van Gestel; R. D. Scott

2004-11-19T23:59:59.000Z

267

Precise asymptotics for the parabolic Anderson model with a moving catalyst or trap  

E-Print Network (OSTI)

We consider the solution $u\\colon [0,\\infty) \\times\\mathbb{Z}^d\\rightarrow [0,\\infty) $ to the parabolic Anderson model, where the potential is given by $(t,x)\\mapsto\\gamma\\delta_{Y_t}\\left(x\\right)$ with $Y$ a simple symmetric random walk on $\\mathbb{Z}^d$. Depending on the parameter $\\gamma\\in[-\\infty,\\infty)$, the potential is interpreted as a randomly moving catalyst or trap. In the trap case, i.e., $\\gamma0$), we consider the solution $u$ from the perspective of the catalyst, i.e., the expression $u(t,Y_t+x)$. Focusing on the cases where moments grow exponentially fast (that is, $\\gamma$ sufficiently large), we describe the moment asymptotics of the expression above up to equivalence. Here, it is crucial to prove the existence of a principal eigenfunction of the corresponding Hamilton operator. While this is well-established for the first moment, we have found an extension to higher moments.

Schnitzler, Adrian

2010-01-01T23:59:59.000Z

268

Using malaise traps to sample ground beetles (Coleoptera: Carabidae).  

SciTech Connect

Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and �¢����trap-shy�¢��� species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

Ulyshen, Michael D., James L. Hanula, and Scott Horn

2005-01-01T23:59:59.000Z

269

Trapping of molecular hydrogen at surfaces via translational-rotational energy conversion  

Science Journals Connector (OSTI)

Using electron-energy-loss spectroscopy (EELS) intensities of rotational transitions and work-function changes as monitors, we show that molecular hydrogen gases, thermal ortho-para H2 mixture, para-H2, D2, and HD, adsorbing on a cold Cu(100) surface have different sticking coefficients. The relative sticking coefficients and the relative populations of ortho- and para-H2 on the surface, as estimated by EELS, can be understood on the basis of a trapping mechanism involving conversion of center-of-mass kinetic energy into rotational energy.

S. Andersson and J. Harris

1983-01-01T23:59:59.000Z

270

Nuclear Fusion for Bose Nuclei Confined in Ion Traps  

SciTech Connect

Nuclear fusion of integer spin nuclei confined in an isotropic ion trap is investigated. Solutions of the ground state for charged bosons trapped in the isotropic harmonic oscillator potential are calculated using the equivalent linear two-body method for many-body problems, which is based on an approximate reduction of the many-body Schroedinger equation by the use of a variational principle. Using the ground-state wave function, theoretical estimates of probabilities and rates for nuclear fusion for Bose nuclei confined in ion traps are obtained. Numerical estimates for fusion rates are presented for the case of deuteron-deuteron fusion.

Kim, Yeong E.; Zubarev, Alexander L. [Purdue University (United States)

2000-03-15T23:59:59.000Z

271

Population trapping in Kr and Xe in intense laser fields  

Science Journals Connector (OSTI)

We have observed trapping of population in Rydberg states of atoms and ions exposed to intense laser radiation. The trapping occurs in nonstationary ‘‘wave-packet’’ superposition states, created, via ac Stark-shifted multiphoton resonances during the laser pulse. The formation of these highly excited bound states requires the nonresonant absorption of up to 20 or more photons; some of the ionic Rydberg states lie nearly 32 eV above the ionic ground state. All of the trapped states having binding energies much less than the photon energy but remain stable against ionization even when the multiphoton ionization probability of the atom is saturated.

R. R. Jones; D. W. Schumacher; P. H. Bucksbaum

1993-01-01T23:59:59.000Z

272

Laser trapping of short-lived radioactive isotopes  

Science Journals Connector (OSTI)

We describe an experiment which demonstrates the feasibility of trapping significant quantities of short-lived radioactive atoms with laser light. A thermal beam of 22.5 sec half-life Na21 atoms was produced on-line at the LBL 88’’ Cyclotron. After decelerating the beam using a Zeeman-tuned slowing technique we stored about 4×103 Na21 atoms in a magneto-optical trap. The number of trapped atoms is large enough to be used in experimental studies of the beta decay of Na21. The basic method can be adapted for other rare isotopes.

Z-T. Lu; C. Bowers; S. J. Freedman; B. K. Fujikawa; J. L. Mortara; S-Q. Shang; K. P. Coulter; L. Young

1994-06-13T23:59:59.000Z

273

Trap seal for open circuit liquid cooled turbines  

DOE Patents (OSTI)

An improved trap seal for open circuit liquid cooled turbines is disclosed. The trap seal of the present invention includes an annular recess formed in the supply conduit of cooling channels formed in the airfoil of the turbine buckets. A cylindrical insert is located in the annular recesses and has a plurality of axial grooves formed along the outer periphery thereof and a central recess formed in one end thereof. The axial grooves and central recess formed in the cylindrical insert cooperate with the annular recess to define a plurality of S-shaped trap seals which permit the passage of liquid coolant but prohibit passage of gaseous coolant.

Grondahl, Clayton M. (Clifton Park, NY); Germain, Malcolm R. (Ballston Lake, NY)

1980-01-01T23:59:59.000Z

274

Trapped Ion Quantum Error Correcting Protocols Using Only Global Operations  

E-Print Network (OSTI)

Quantum error-correcting codes are many-body entangled states that are prepared and measured using complex sequences of entangling operations. Each element of such an entangling sequence introduces noise to delicate quantum information during the encoding or reading out of the code. It is important therefore to find efficient entangling protocols to avoid the loss of information. Here we propose an experiment that uses only global entangling operations to encode an arbitrary logical qubit to either the five-qubit repetition code or the five-qubit code, with a six-ion Coulomb crystal architecture in a Penning trap. We show that the use of global operations enables us to prepare and read out these codes using only six and ten global entangling pulses, respectively. The proposed experiment also allows the acquisition of syndrome information during readout. We provide a noise analysis for the presented protocols, estimating that we can achieve a six-fold improvement in coherence time with noise as high as $\\sim 1\\%$ on each entangling operation.

Joseph F. Goodwin; Benjamin J. Brown; Graham Stutter; Howard Dale; Richard C. Thompson; Terry Rudolph

2014-07-07T23:59:59.000Z

275

Constitutive Model for the Time-Dependent Mechanical Behavior of 430 Stainless Steel and FeCrAlY Foams in Sulfur-Bearing Environments  

SciTech Connect

The mechanical behavior of 430 stainless steel and pre-oxidized FeCrAlY open-cell foam materials of various densities was evaluated in compression at temperatures between 450 C and 600 C in an environment containing hydrogen sulfide and water vapor. Both materials showed negligible corrosion due to the gaseous atmosphere for up to 168 hours. The monotonic stress-strain response of these materials was found to be dependent on both the strain rate and their density, and the 430 stainless steel foam materials exhibited less stress relaxation than FeCrAlY for similar experimental conditions. Using the results from multiple hardening-relaxation and monotonic tests, an empirical constitutive equation was derived to predict the stress-strain behavior of FeCrAlY foams as a function of temperature and strain rate. These results are discussed in the context of using these materials in a black liquor gasifier to accommodate the chemical expansion of the refractory liner resulting from its reaction with the soda in the black liquor.

Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL

2013-01-01T23:59:59.000Z

276

Purple traps yield Reservation's first detection of Emerald Ash Borer  

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

traps yield Reservation's first detection of Emerald Ash Borer traps yield Reservation's first detection of Emerald Ash Borer The question of whether or not DOE's forests are infested with Emerald Ash Borer (EAB) has been answered. On May 10, a trap on Highway 95 at the Highway 58 interchange produced the first instance of the destructive non-native insect in Roane County. Five days later, a second trap on Bethel Valley Road near the East Portal turned up the first capture in Anderson County. "Unfortunately, these finds signal the beginning of a decline of ash species throughout the reservation" according to Greg Byrd, forester with the ORNL Natural Resources Program. "Dieback will become more prominent as the insect populations expand. Native ash trees have little defense against this pest, which was

277

Laser ablation loading of a surface-electrode ion trap  

E-Print Network (OSTI)

We demonstrate loading by laser ablation of $^{88}$Sr$^+$ ions into a mm-scale surface-electrode ion trap. The laser used for ablation is a pulsed, frequency-tripled Nd:YAG with pulse energies of 1-10 mJ and durations of 3-5 ns. An additional laser is not required to photoionize the ablated material. The efficiency and lifetime of several candidate materials for the laser ablation target are characterized by measuring the trapped ion fluorescence signal for a number of consecutive loads. Additionally, laser ablation is used to load traps with a trap depth (40 meV) below where electron impact ionization loading is typically successful ($\\gtrsim$ 500 meV).

David R. Leibrandt; Robert J. Clark; Jaroslaw Labaziewicz; Paul Antohi; Waseem Bakr; Kenneth R. Brown; Isaac L. Chuang

2007-06-22T23:59:59.000Z

278

Coherent control of a qubit is trap-free  

E-Print Network (OSTI)

There is a strong interest in optimal manipulating of quantum systems by external controls. Traps are controls which are optimal only locally but not globally. If they exist, they can be serious obstacles to the search of globally optimal controls in numerical and laboratory experiments, and for this reason the analysis of traps attracts considerable attention. In this paper we prove that for a wide range of control problems for two-level quantum systems all locally optimal controls are also globally optimal. Hence we conclude that two-level systems in general are trap-free. In particular, manipulating qubits---two-level quantum systems forming a basic building block for quantum computation---is free of traps for fundamental problems such as the state preparation and gate generation.

Alexander Pechen; Nikolay Il'in

2014-07-19T23:59:59.000Z

279

Electron source for a mini ion trap mass spectrometer  

DOE Patents (OSTI)

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Dietrich, D.D.; Keville, R.F.

1995-12-19T23:59:59.000Z

280

Electron source for a mini ion trap mass spectrometer  

DOE Patents (OSTI)

An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

A bosonic Josephson junction controlled by a single trapped ion  

E-Print Network (OSTI)

We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a small $^{87}$Rb Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate interwell coupling rates reaching 100 Hz, while the state dependence amounts to 10s of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The system could be realized in an experiment by combining trapped ions with optical dipole traps for cold atoms or in a combined atom-ion micro trap, where both approaches are within reach using current technology.

Gerritsma, R; Doerk, H; Idziaszek, Z; Calarco, T; Schmidt-Kaler, F

2011-01-01T23:59:59.000Z

282

Mass Spectrometer: Linear Ion Trap Quadrupole (LTQ) Orbitrap...  

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

Ion Trap Quadrupole (LTQ) Orbitrap MS - for environmental research (nanoDESI) Instrument ID: 34068 Availability: 10 hours a day, 5 days a week Quick Specs Science Contact Science...

283

Quantum gates, sensors, and systems with trapped ions  

E-Print Network (OSTI)

Quantum information science promises a host of new and useful applications in communication, simulation, and computational algorithms. Trapped atomic ions are one of the leading physical systems with potential to implement ...

Wang, Shannon Xuanyue

2012-01-01T23:59:59.000Z

284

Pt-free, Perovskite-based Lean NOx Trap Catalysts  

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

Conference Pt-free, Perovskite-based Lean NO x Trap Catalysts Gongshin Qi, Chang H. Kim, and Wei Li GM Global Research & Development 2010 DEER Conference Overview LNT Chemistry...

285

On the generation of bottom-trapped internal tides  

Science Journals Connector (OSTI)

The interaction of the barotropic tide with the bottom topography when the tidal frequency ? is smaller than the Coriolis frequency f is examined. The resulting waves are called bottom-trapped internal tides. The energy density associated with ...

Saeed Falahat; Jonas Nycander

286

Brief Communication 1195 A gene trap approach in Xenopus  

E-Print Network (OSTI)

developed several gene trap vectors, using the green fluorescent protein (GFP) as a marker. Using, including expression in the epiphysis, the olfactory bulb and placodes, the eyes, ear, brain, muscles, tail

Amaya, Enrique

287

Quantum state engineering in ion-traps via adiabatic passage  

Science Journals Connector (OSTI)

We propose two relatively robust schemes to generate entangled W states of three (or generally N) ions in ion trap systems by using adiabatic passage technique and appropriately designed ion-field couplings in a ...

M. Amniat-Talab; M. Saadati-Niari; S. Guérin

2012-08-01T23:59:59.000Z

288

Light trapping limits in plasmonic solar cells: an analytical investigation  

E-Print Network (OSTI)

We analytically investigate the light trapping performance in plasmonic solar cells with Si/metallic structures. We consider absorption enhancements for surface plasmon polaritons (SPPs) at planar Si/metal interfaces and ...

Sheng, Xing

289

Novel trapping techniques for shaping Bose-Einstein condensates  

E-Print Network (OSTI)

A combination of radio frequency radiation and magnetic field gradients was used to trap atoms in dressed states. In a magnetic field with a quadrupole minimum. RF fields resonant with the (I F. m)) 11. -1) -- 1, 0) ...

Boyd, Micah (Micah Scott)

2007-01-01T23:59:59.000Z

290

Light Trapping, Absorption and Solar Energy Harvesting by Artificial Materials  

SciTech Connect

We provide designs of thin-film solar cells utilizing optimized photonic-crystal light-trapping and numerical simulations of their solar-to-electrical power conversion efficiencies.

John, Sajeev [University of Toronto

2014-08-15T23:59:59.000Z

291

Laser induced rotation of trapped chiral and achiral nematic droplets  

E-Print Network (OSTI)

We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.

Marjan Mosallaeipour; Yashodhan Hatwalne; N. V. Madhusudana; Sharath Ananthamurthy

2010-02-05T23:59:59.000Z

292

Trapped surfaces in Oppenheimer-Snyder black holes  

E-Print Network (OSTI)

The Oppenheimer-Snyder solution models a homogeneous round dust cloud collapsing to a black hole. Inside its event horizon there is a region through which trapped surfaces pass. We try to determine exactly where the boundary of this region meets the centre of the cloud. We present explicit examples of the relevant trapped (topological) spheres; they extend into the exterior vacuum region, and are carefully matched at the junction between the cloud and the vacuum.

Ingemar Bengtsson; Emma Jakobsson; José M. M. Senovilla

2013-06-27T23:59:59.000Z

293

The Engineered Approach to Energy and Maintenance Effective Steam Trapping  

E-Print Network (OSTI)

., Chemical Engineering 9/1/75. 4. Maintenance Engineering, May 1976. 5. "How Much Does Lost Steam Cost",Armstrong Machine works, Hydrocarbon Processing, p.129, Jan. 1976. 6. "Setter Steam Trapping Cuts Energy Waste", wesley Yates, Yarway Corp..., Georgia Tech Industrial Energy Extension Service, Chemical Engineering, 2/11/80. 10. ''Basic Facts & Enerqv Saving Tips" ,Lawrence R. O'Dell, Armstrong Machine Works, Heating/Piping/ Air Conditioning, May 1977. 11. Steam Trap Report - Energy Loss...

Krueger, R. G.; Wilt, G. W.

1980-01-01T23:59:59.000Z

294

Design and operation of the electron beam ion trap  

SciTech Connect

This report describes the basic features and operating principles of the Electron Beam Ion Trap. The differences between EBIT and other sources of highly charged ions are outlined. Its features and operating parameters are discussed. The report also explains why certain design choices were necessary and the constraints involved in building an electron beam ion trap. EBIT's evaporation cooling system is described in detail. 13 refs., 8 figs.

Vogel, D.

1990-05-30T23:59:59.000Z

295

Magnetic line trapping and effective transport in stochastic magnetic fields  

Science Journals Connector (OSTI)

The transport of collisional particles in stochastic magnetic fields is studied using the decorrelation trajectory method. The nonlinear effect of magnetic line trapping is considered together with particle collisions. The running diffusion coefficient is determined for arbitrary values of the statistical parameters of the stochastic magnetic field and of the collisional velocity. The effect of the magnetic line trapping is determined. New anomalous diffusion regimes are found.

M. Vlad; F. Spineanu; J. H. Misguich; R. Balescu

2003-02-07T23:59:59.000Z

296

Trapped-ion cell with improved DC potential harmonicity for FT-ICR MS  

SciTech Connect

The trapped-ion cell is a key component critical for optimal performance in Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS). We have upgraded our 12 Tesla FT-ICR instrument with a new open cylindrical cell that includes four additional cylindrical segments that serve as compensation electrodes. The DC potential on the additional segments can be set to specific pre-calculated values to suppress DC trapping field anharmonicity, in an effort to improve coherence of the ion cyclotron motion and minimize deviations from the calibration function of the ideal cell. Alternatively, the compensation potentials can be set equal to potentials of adjacent cell electrodes, which creates a DC potential distribution equivalent to that of a regular open cylindrical cell. The initial experimental characterization of both the compensated and open cell configurations was performed using ESI direct infusion of a peptide mixture. Operating the compensated cell at increased post-excitation radii resulted in improved mass measurement accuracy together with increased signal intensity, while the regular configuration exhibited peak splitting and reduced signal life time under these operating conditions. The observed improvement of the compensated cell performance was consistent with the expected behavior due to the improved DC potential harmonicity. These results confirm that the trapping DC potential harmonicity is significant for optimizing FT-ICR MS performance.

Tolmachev, Aleksey V.; Robinson, Errol W.; Wu, Si; Kang, Hyuk; Lourette, Natacha M.; Pasa-Tolic, Ljiljana; Smith, Richard D.

2008-04-01T23:59:59.000Z

297

EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994  

SciTech Connect

The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA`s astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th{sup 80+} can be performed routinely. Measurements of the rates and cross sections for electron transfer from H{sub 2} performed to determine the lifetime of HCI up to Xe{sup q+} and Th{sup q+} (35 {le} q {le} 80) have been studied at mean energies estimated to be {approximately} 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events.

Schneider, D. [ed.

1995-10-01T23:59:59.000Z

298

Ion-trap measurements of electric-field noise near surfaces  

E-Print Network (OSTI)

Electric-field noise near surfaces is a common problem in diverse areas of physics, and a limiting factor for many precision measurements. There are multiple mechanisms by which such noise is generated, many of which are poorly understood. Laser-cooled, trapped ions provide one of the most sensitive systems to probe electric-field noise at MHz frequencies and over a distance range 30 - 3000 $\\mu$m from the surface. Over recent years numerous experiments have reported spectral densities of electric-field noise inferred from ion heating-rate measurements and several different theoretical explanations for the observed noise characteristics have been proposed. This paper provides an extensive summary and critical review of electric-field noise measurements in ion traps, and compares these experimental findings with known and conjectured mechanisms for the origin of this noise. This reveals that the presence of multiple noise sources, as well as the different scalings added by geometrical considerations, complicate the interpretation of these results. It is thus the purpose of this review to assess which conclusions can be reasonably drawn from the existing data, and which important questions are still open. In so doing it provides a framework for future investigations of surface-noise processes.

M. Brownnutt; M. Kumph; P. Rabl; R. Blatt

2014-09-23T23:59:59.000Z

299

On biodiversity conservation and poverty traps  

Science Journals Connector (OSTI)

...economic, social, and political approaches to achieve biodiversity...describe a unique index insurance mechanism they designed...the relative merits and risks of alternative courses of action...Stochastic wealth dynamics and risk management among a poor population . Econ...Chantarat S ( 2011 ) Index insurance for pro-poor conservation...

Christopher B. Barrett; Alexander J. Travis; Partha Dasgupta

2011-01-01T23:59:59.000Z

300

Characteristics of trap-filled gallium arsenide photoconductive switches used in high gain pulsed power applications  

SciTech Connect

The electrical properties of semi-insulating (SI) Gallium Arsenide (GaAs) have been investigated for some time, particularly for its application as a substrate in microelectronics. Of late this material has found a variety of applications other than as an isolation region between devices, or the substrate of an active device. High resistivity SI GaAs is increasingly being used in charged particle detectors and photoconductive semiconductor switches (PCSS). PCSS made from these materials operating in both the linear and non-linear modes have applications such as firing sets, as drivers for lasers, and in high impedance, low current Q-switches or Pockels cells. In the non-linear mode, it has also been used in a system to generate Ultra-Wideband (UWB) High Power Microwaves (HPM). The choice of GaAs over silicon offers the advantage that its material properties allow for fast, repetitive switching action. Furthermore photoconductive switches have advantages over conventional switches such as improved jitter, better impedance matching, compact size, and in some cases, lower laser energy requirement for switching action. The rise time of the PCSS is an important parameter that affects the maximum energy transferred to the load and it depends, in addition to other parameters, on the bias or the average field across the switch. High field operation has been an important goal in PCSS research. Due to surface flashover or premature material breakdown at higher voltages, most PCSS, especially those used in high power operation, need to operate well below the inherent breakdown voltage of the material. The lifetime or the total number of switching operations before breakdown, is another important switch parameter that needs to be considered for operation at high bias conditions. A lifetime of {approximately} 10{sup 4} shots has been reported for PCSS's used in UWB-HPM generation [5], while it has exceeded 10{sup 8} shots for electro-optic drivers. Much effort is currently being channeled in the study related to improvements of these two parameters high bias operation and lifetime improvement for switches used in pulsed power applications. The contact material and profiles are another important area of study. Although these problems are being pursued through the incorporation of different contact materials and introducing doping near contacts, it is important that the switch properties and the conduction mechanism in these switches be well understood such that the basic nature of the problems can be properly addressed. In this paper the authors report on these two basic issues related to the device operation, i.e., mechanisms for increasing the hold-off characteristics through neutron irradiation, and the analysis of transport processes at varying field conditions in trap dominated SI GaAs in order to identify the breakdown mechanism during device operation. It is expected that this study would result in a better understanding of photoconductive switches, specifically those used in high power operation.

ISLAM,N.E.; SCHAMILOGLU,E.; MAR,ALAN; LOUBRIEL,GUILLERMO M.; ZUTAVERN,FRED J.; JOSHI,R.P.

2000-05-30T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

High-Precision Test of Landauer’s Principle in a Feedback Trap  

Science Journals Connector (OSTI)

We confirm Landauer’s 1961 hypothesis that reducing the number of possible macroscopic states in a system by a factor of 2 requires work of at least kTln2. Our experiment uses a colloidal particle in a time-dependent, virtual potential created by a feedback trap to implement Landauer’s erasure operation. In a control experiment, similar manipulations that do not reduce the number of system states can be done reversibly. Erasing information thus requires work. In individual cycles, the work to erase can be below the Landauer limit, consistent with the Jarzynski equality.

Yonggun Jun; Mom?ilo Gavrilov; John Bechhoefer

2014-11-04T23:59:59.000Z

302

Born-Oppenheimer description of two atoms in a combined oscillator and lattice trap  

E-Print Network (OSTI)

We analyze the quantum states of two atoms in a combined harmonic oscillator and periodic lattice trap in one spatial dimension. In the case of tight-binding and only nearest neighbor tunneling, the equations of motion are conveniently represented in the momentum representation. We show that in the case of strong attraction between the particles, the di?erent time scales of relative and center-of-mass motion validate a separation of the problem similar to the Born-Oppenheimer approximation applied in the description of electronic and nuclear motion in molecules.

Ole Søe Sørensen; Klaus Mølmer

2012-06-26T23:59:59.000Z

303

Modulational instability of a trapped Bose-Einstein condensate with two- and three-body interactions  

Science Journals Connector (OSTI)

We investigate analytically and numerically the modulational instability of a Bose-Einstein condensate with both two- and three-body interatomic interactions and trapped in an external parabolic potential. Analytical investigations performed lead us to establish an explicit time-dependent criterion for the modulational instability of the condensate. The effects of the potential as well as of the quintic nonlinear interaction are studied. Direct numerical simulations of the Gross-Pitaevskii equation with two- and three-body interactions describing the dynamics of the condensate agree with the analytical predictions.

Etienne Wamba; Alidou Mohamadou; Timoléon C. Kofané

2008-04-23T23:59:59.000Z

304

Artificial trapping of a stable high-density dipolar exciton fluid  

Science Journals Connector (OSTI)

We present compelling experimental evidence for a successful electrostatic trapping of two-dimensional dipolar excitons that results in stable formation of a well-confined, high-density and spatially uniform dipolar exciton fluid. We show that, for at least half a microsecond, the exciton fluid sustains a density higher than the critical density for degeneracy if the exciton fluid temperature reaches the lattice temperature within that time. This method should allow for the study of strongly interacting bosons in two dimensions at low temperatures, and possibly lead towards the observation of quantum phase transitions of two-dimensional interacting excitons, such as superfluidity and crystallization.

Gang Chen, Ronen Rapaport, L. N. Pffeifer, K. West, P. M. Platzman, Steven Simon, Z. Vörös, and D. Snoke

2006-07-14T23:59:59.000Z

305

EXPERIMENTAL STUDY OF ION INJECTION INTO AN EXTENDED TRAP OF THE BNL EBIS.  

SciTech Connect

Experiments on the BNL EBIS Test Stand (EBTS) with the ion trap extending beyond the edges of the superconducting solenoid had the main goal to study ion trap operation with a trap length exceeding that of the normal EBTS trap. Preliminary results indicate that the ion trap with length 107 cm is stable and controllable in the same fashion as our normal 70 cm trap with a multiampere electron beam. EBTS operation with ion trap 145 cm long and with electron current up to 3 A in earlier experiments also was stable and yielded more ions than from the basic ''short'' trap. These results increased our confidence in operation of the proposed RHIC in a stable mode and in the correctness of linear scaling of ion intensity with the length of the ion trap.

PIKIN,A.; ALESSI,J.; BEEBE,E.; KPONOU,A.; PRELEC,K.

2001-09-02T23:59:59.000Z

306

Coulomb crystal mass spectrometry in a digital ion trap  

E-Print Network (OSTI)

We present a mass spectrometric technique for identifying the masses and relative abundances of Coulomb-crystallized ions held in a linear Paul trap. A digital radiofrequency waveform is employed to generate the trapping potential, as this can be cleanly switched off, and static dipolar fields subsequently applied to the trap electrodes for ion ejection. Excellent detection efficiency is demonstrated for Ca+ and CaF+ ions from bi-component Ca+/CaF+ Coulomb crystals prepared by reaction of Ca+ with CH3F. A quantitative linear relationship is observed between ion number and the corresponding integrated TOF peak, independent of the ionic species. The technique is applicable to a diverse range of multi-component Coulomb crystals - demonstrated here for Ca+/NH3+/NH4+ and Ca+/CaOH+/CaOD+ crystals - and will facilitate the measurement of ion-molecule reaction rates and branching ratios in complicated reaction systems.

Deb, Nabanita; Smith, Alexander D; Keller, Matthias; Rennick, Christopher J; Heazlewood, Brianna R; Softley, Timothy P

2015-01-01T23:59:59.000Z

307

Trapped-flux internal-dipole superconducting motor/generator.  

SciTech Connect

A new class of motor/generator (M/G) utilizes the magnetic flux trapping capability of high-temperature superconductors (HTSs). The rotor, consists of a cylindrical shell composed of HTS segments. These segments act as trapped-field magnets, magnetized in such a way that a dipole magnetic field is produced in the interior of the shell. A stator coil assembly is placed in the interior of the shell and current passing through the conductors of the coil produce a rotational torque, either as a hysteresis motor or as a synchronous motor. The coil may be either conventional, with copper wires and an iron core, or composed of superconductors and can be used to establish the trapped fields in the HTSs.

Hull, J. R.

1998-09-03T23:59:59.000Z

308

Trapped Ion Chain Thermometry and Mass Analysis Through Imaging  

E-Print Network (OSTI)

We demonstrate the temperature measurement of individual laser cooled ions in a linear Coulomb crystal by relating their imaged spatial extent along the linear Paul trap axis to the normal modes of vibration of coupled oscillators in a harmonic potential. We also use the thermal spatial spread of `bright' ions in the case of a two-species mixed chain to measure the secular resonance frequency of vibration of the center-of-mass mode of the entire chain and infer the molecular composition of the co-trapped `dark' ions. These techniques create new possibilities for better understanding of sympathetic cooling in mixed-ion chains and under conditions of non-uniform heat load, improving few-ion mass spectrometry, and making in-situ temperature measurements of individual trapped ions without requiring a scan over the Doppler cooling parameters.

V. Rajagopal; J. P. Marler; M. G. Kokish; B. C. Odom

2014-08-06T23:59:59.000Z

309

Trapped Ion Chain Thermometry and Mass Analysis Through Imaging  

E-Print Network (OSTI)

We demonstrate the temperature measurement of individual laser cooled ions in a linear Coulomb crystal by relating their imaged spatial extent along the linear Paul trap axis to the normal modes of vibration of coupled oscillators in a harmonic potential. We also use the thermal spatial spread of `bright' ions in the case of a two-species mixed chain to measure the secular resonance frequency of vibration of the center-of-mass mode of the entire chain and infer the molecular composition of the co-trapped `dark' ions. These techniques create new possibilities for better understanding of sympathetic cooling in mixed-ion chains and under conditions of non-uniform heat load, improving few-ion mass spectrometry, and making in-situ temperature measurements of individual trapped ions without requiring a scan over the Doppler cooling parameters.

Rajagopal, V; Kokish, M G; Odom, B C

2014-01-01T23:59:59.000Z

310

Absorption by cold Fermi atoms in a harmonic trap  

E-Print Network (OSTI)

We study the absorption spectrum for a strongly degenerate Fermi gas confined in a harmonic trap. The spectrum is calculated using both the exact summation and also the Thomas-Fermi (TF) approximation. In the latter case, relatively simple analytical expressions are obtained for the absorption lineshape at large number of trapped atoms. At zero temperature, the approximated lineshape is characterized by a $(1-z^2)^{5/2}$ dependence which agrees well with the exact numerical calculations. At non-zero temperature, the spectrum becomes broader, although remains non-Gaussian as long as the fermion gas is degenerate. The changes in the trap frequency for an electronically excited atom can introduce an additional line broadening.

Gediminas Juzeliunas; Marius Masalas

2000-11-10T23:59:59.000Z

311

Storing Electrons Instead of Positrons Without Trapping of Positive Ions  

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

Electrons Instead of Positrons Without Electrons Instead of Positrons Without Trapping of Positive Ions LS-75 T. K. Khoe October, 1986 In this note, a procedure to inject and store electrons in the ring without trapping ions will be described. The minimum injection current per bunch below which ion trapping occur will be determined. Since the vertical beam size is smaller than the horizontal beam size, we will consider the vertical motion only. The following assumptions are made: 1. The bunch period is much longer than the bunch length. This assumption allow us to use the thin lens approximation for the focusing effect of the electron bunch. 2. The bunch length is much larger than the transverse dimensions of the beam. A two-dimensional calculation can then be used to obtain the

312

Quantum Phase Transitions in a Linear Ion Trap  

E-Print Network (OSTI)

We show that the quantum phase transition of the Tavis-Cummings model can be realised in a linear ion trap of the kind proposed for quantum computation. The Tavis-Cummings model describes the interaction between a bosonic degree of freedom and a collective spin. In an ion trap, the collective spin system is a symmetrised state of the internal electronic states of N ions, while the bosonic system is the vibrational degree of freedom of the centre of mass mode for the ions.

G. J. Milburn; Paul Alsing

2000-03-01T23:59:59.000Z

313

Sympathetic Cooling with Two Atomic Species in an Optical Trap  

Science Journals Connector (OSTI)

We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a CO2 laser and study the exchange of thermal energy between the gases. The optically cooled cesium gas efficiently decreases the temperature of the lithium gas through sympathetic cooling. Equilibrium temperatures down to 25 ?K have been reached. The measured cross section for thermalizing 133Cs-7Li collisions is 8×10-12 cm2, for both species unpolarized in their lowest hyperfine ground state. Besides thermalization, we observe evaporation of lithium purely through elastic cesium-lithium collisions (sympathetic evaporation).

M. Mudrich; S. Kraft; K. Singer; R. Grimm; A. Mosk; M. Weidemüller

2002-06-07T23:59:59.000Z

314

What To Do With Cold Traps and Why  

E-Print Network (OSTI)

of the 2012 Industrial Energy Technology Conference New Orleans, Louisiana, May 29-June 1, 2012 TABLE!1 Failure!Event Historical!Value Flare!Nozzle!Replacement $750,000! Analyzer!Failure!Plant!Shutdown $1,000,000! Flare"out!Fine $1,700,000! Gas... Orleans, Louisiana, May 29-June 1, 2012 TABLE!7 Failure!Events Annual!Cost!/!Trap (360!Traps!in!Unit) Flare!Nozzle!Replacement $694 Analyzer!Failure!Shuts!Plant $1,389 Flare"out!Fine $3,148 Gas!Compressor!Failure $5,000 Main!Turbine!Failure $11...

Risko, J. R.; Walter, J. P.

2012-01-01T23:59:59.000Z

315

Ion trapping in the emitter sheath in thermionic converters  

SciTech Connect

The effect of ion trapping in the emitter sheath in ignited thermionic converters is studied. The ion trapping prevents the emitter-sheath barrier from being higher than approximately 0.1 eV, when the current decreases in the converter. This gives a condition for the constriction of the arc. I-V curves are calculated for an ignited thermionic converter with a hydrodynamic plasma theory that takes into account the effect of Coulomb scattering and volume recombination, but assumes that the electron temperature is constant in the plasma.

Lundgren, L.

1985-12-01T23:59:59.000Z

316

Revealing the escape mechanism of three-dimensional orbits in a tidally limited star cluster  

E-Print Network (OSTI)

The aim of this work is to explore the escape process of three-dimensional orbits in a star cluster rotating around its parent galaxy in a circular orbit. The gravitational field of the cluster is represented by a smooth, spherically symmetric Plummer potential, while the tidal approximation was used to model the steady tidal field of the galaxy. We conduct a thorough numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. It is of particular interest to locate the escape basins towards the two exit channels and relate them with the corresponding escape times of the orbits. For this purpose, we split our investigation into three cases depending on the initial value of the $z$ coordinate which was used for launching the stars. The most noticeable finding is that the majority of stars initiated very close to the primary $(x,y)$ plane move in chaotic orbits and they remain trapped for vast time intervals, while orbits with relatively high values of $z_0$ on the other hand, form well-defined basins of escape. It was also observed, that for energy levels close to the critical escape energy the escape rates of orbits are large, while for much higher values of energy most of the orbits have low escape periods or they escape immediately to infinity. We hope our outcomes to be useful for a further understanding of the dissolution process and the escape mechanism in open star clusters.

Euaggelos E. Zotos

2014-11-18T23:59:59.000Z

317

Trapping dynamics of disilane on bare and monohydride-terminated Si(100)-2×1  

Science Journals Connector (OSTI)

The initial trapping probability of disilane on bare and monohydride-terminated Si(100)-2×1 surfaces was measured using molecular beam techniques. On the bare surface, trapping is shown to be very efficient, with near unit trapping probability at incident kinetic energies up to 0.2 eV, and nearly 50% trapping at 1 eV kinetic energy. The monohydride-terminated surface displays significantly less trapping efficiency than the bare surface. Interestingly, trapping probabilities decrease as the angle of incidence is increased, with the decrease becoming more pronounced at higher kinetic energies; this effect is discussed in terms of parallel momentum accommodation dynamics.

B.A. Ferguson; C.T. Reeves; C.B. Mullins

1999-01-01T23:59:59.000Z

318

Operation of a planar-electrode ion trap array with adjustable RF electrodes  

E-Print Network (OSTI)

One path to scaling-up trapped atomic ions for large-scale quantum computing and simulation is to create a two-dimensional array of ion traps in close proximity to each other. A method to control the interactions between nearest neighboring ions is demonstrated and characterized here, using an adjustable radio-frequency (RF) electrode between trapping sites. A printed circuit board planar-electrode ion trap is demonstrated, trapping laser-cooled $^{40}$Ca$^+$ ions. RF shuttling and secular-frequency adjustment are shown as a function of the power applied to the addressed RF electrode. The trapped ion's heating rate is measured via a fluorescence recooling method.

Muir Kumph; Philip Holz; Kirsten Langer; Michael Niedermayr; Michael Brownnutt; Rainer Blatt

2014-02-04T23:59:59.000Z

319

Investigation of the reaction of OH and CO to form H and CO? by photoelectron-photofragment coincidence spectroscopy in a cryogenic ion beam trap  

E-Print Network (OSTI)

spectroscopy in a cryogenic ion beam trap A dissertationspectroscopy in a cryogenic ion beam trap by Christopherof the inclusion of a cryogenic ion beam trap, and its

Johnson, Christopher Joseph

2011-01-01T23:59:59.000Z

320

Enhancing DNA binding rate using optical trapping of high-density gold nanodisks  

SciTech Connect

We present the dynamic study of optical trapping of fluorescent molecules using high-density gold nanodisk arrays. The gold nanodisks were fabricated by electron beam lithography with a diameter of 500 nm and a period of 1 ?m. Dark-field illumination showed ?15 times enhancement of fluorescence near edges of nanodisks. Such enhanced near-field generated an optical trapping force of ?10 fN under 3.58 × 10{sup 3} W/m{sup 2} illumination intensity as calculated from the Brownian motions of 590 nm polystyrene beads. Kinetic observation of thiolated DNA modified with Cy5 dye showed different binding rates of DNA under different illumination intensity. The binding rate increased from 2.14 × 10{sup 3} s{sup ?1} (I = 0.7 × 10{sup 3} W/m{sup 2}) to 1.15 × 10{sup 5} s{sup ?1} (I = 3.58 × 10{sup 3} W/m{sup 2}). Both enhanced fluorescence and binding rate indicate that gold nanodisks efficiently improve both detection limit and interaction time for microarrays.

Lin, En-Hung; Pan, Ming-Yang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China) [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Lee, Ming-Chang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China)] [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Wei, Pei-Kuen, E-mail: pkwei@sinica.edu.tw [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China) [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Institute of Biophotonics, National Yang-Ming University, Taipei 11221, Taiwan (China)

2014-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Paul trapping of charged particles in aqueous solution  

Science Journals Connector (OSTI)

...1]. Oxygen plasma treatment was...surrounding ionic atmosphere to the motion of...ii) Trapping with large fluctuations...V) Frequency (MHz) b q a i 1...with the surface area of the particle...V, and f=2.5 MHz, using the device...

Weihua Guan; Sony Joseph; Jae Hyun Park; Predrag S. Krsti?; Mark A. Reed

2011-01-01T23:59:59.000Z

322

Reversed magnetization A NOVEL DEVICE FOR CONTINUOUS FLOW MAGNETIC TRAPPING  

E-Print Network (OSTI)

1. 3 µm5 µm Reversed magnetization A NOVEL DEVICE FOR CONTINUOUS FLOW MAGNETIC TRAPPING AND SORTING Martin d'hères, France ABSTRACT The manipulation of magnetically labeled bio-objects of nano or micrometer sizes is now realizable by combining the magnetic forces with microfluidics. This paper reports

Paris-Sud XI, Université de

323

Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons  

E-Print Network (OSTI)

The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons (UCN) in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing sci...

O'Shaughnessy, C M; Schelhammer, K W; Swank, C M; Seo, P -N; Huffman, P R; Dzhosyuk, S N; Mattoni, C E H; Yang, L; Doyle, J M; Coakley, K J; Thompson, A K; Mumm, H P; Lamoreaux, S K; Yang, G

2009-01-01T23:59:59.000Z

324

Non-Diversification Traps in Catastrophe Insurance Markets Rustam Ibragimov  

E-Print Network (OSTI)

markets, even though there is a large enough market capacity to reach full risk sharing throughNon-Diversification Traps in Catastrophe Insurance Markets Rustam Ibragimov Dwight Jaffee Johan Walden§ Abstract We develop a model for markets for catastrophic risk. The model explains why insurance

Chaudhuri, Sanjay

325

Gene Traps: Tools for Plant Development and Genomics  

Science Journals Connector (OSTI)

...activates GFP expression from the UAS. A battery of enhancer trap lines expressing this...genomic DNA flanking the insertions (). Thermal asymmetric interlaced PCR is particularly...Arabidopsis thaliana T-DNA insert junctions by thermal asymmetric interlaced PCR Lloyd A.M...

Patricia S. Springer

326

The TITAN in-trap decay spectroscopy facility at TRIUMF  

E-Print Network (OSTI)

This article presents an upgraded in-trap decay spectroscopy apparatus which has been developed and constructed for use with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). This device consists of an open-access electron-beam ion-trap (EBIT), which is surrounded radially by seven low-energy planar Si(Li) detectors. The environment of the EBIT allows for the detection of low-energy photons by providing backing-free storage of the radioactive ions, while guiding charged decay particles away from the trap centre via the strong (up to 6 T) magnetic field. In addition to excellent ion confinement and storage, the EBIT also provides a venue for performing decay spectroscopy on highly-charged radioactive ions. Recent technical advancements have been able to provide a significant increase in sensitivity for low-energy photon detection, towards the goal of measuring weak electron-capture branching ratios of the intermediate nuclei in the two-neutrino double beta ($2\

K. G. Leach; A. Grossheim; A. Lennarz; T. Brunner; J. R. Crespo López-Urrutia; A. T. Gallant; M. Good; R. Klawitter; A. A. Kwiatkowski; T. Ma; T. D. Macdonald; S. Seeraji; M. C. Simon; C. Andreoiu; J. Dilling; D. Frekers

2014-05-28T23:59:59.000Z

327

Trapping and Frequency Variability in Electron Acoustic Waves  

E-Print Network (OSTI)

Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma Langmuir waves, and at large excitations resonance is observed over a broad range. Laser Induced

California at San Diego, University of

328

Quantum Reservoir Engineering with Laser Cooled Trapped Ions  

Science Journals Connector (OSTI)

We show how to design different couplings between a single ion trapped in a harmonic potential and an environment. The coupling is due to the absorption of a laser photon and subsequent spontaneous emission. The variation of the laser frequencies and intensities allows one to “engineer” the coupling and select the master equation describing the motion of the ion.

J. F. Poyatos; J. I. Cirac; P. Zoller

1996-12-02T23:59:59.000Z

329

Light Trapping in Solar Cells Using Resonant Nanostructures P. Spinelli  

E-Print Network (OSTI)

Light Trapping in Solar Cells Using Resonant Nanostructures P. Spinelli #12;Summary Photovoltaics solar cell is reduced, due to incomplete absorption of light. In this thesis, we investigate new ways of enhancing light absorption in Si solar cells by using nanostructures that show resonant interaction

van Rooij, Robert

330

Landau Damping of Spin Waves in Trapped Boltzmann Gases  

E-Print Network (OSTI)

levels of trapped ultra-cold 87Rb atoms in the nondegenerate regimes. As in spin-polarized Boltzmann) where is the mean-field frequency, S+(z) = s+(z, p)n(p) dp and n(p) = (2mkBT)-1/2 exp[-p2/(2mk

Mullin, William J.

331

Momentum distribution and correlation function of quasicondensates in elongated traps  

Science Journals Connector (OSTI)

We calculate the spatial correlation function and momentum distribution of a phase-fluctuating, elongated three-dimensional condensate in a trap and in free expansion. We take the inhomogeneous density profile into account via a local-density approximation. We find an almost Lorentzian momentum distribution, in stark contrast with a Heisenberg-limited Thomas-Fermi condensate.

F. Gerbier; J. H. Thywissen; S. Richard; M. Hugbart; P. Bouyer; A. Aspect

2003-05-27T23:59:59.000Z

332

Multiple isotope magneto-optical trap from a single diode laser  

Science Journals Connector (OSTI)

We present a dual isotope magneto-optical trap produced using a single diode laser. We generate all the optical frequencies needed for trapping both species using a fiber intensity...

Valenzuela, Victor Manuel; Hamzeloui, Saeed; Gutiérrez, Monica; Gomez, Eduardo

2013-01-01T23:59:59.000Z

333

GreenPower Trap Water-Muffler System | Department of Energy  

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

GreenPower Trap Water-Muffler System GreenPower Trap Water-Muffler System This hydrated EGR system reduces NOx and enhances fuel efficiency, and the DPF is catalyzed by the...

334

Loading a planar RF Paul Trap from a cold Yb? source  

E-Print Network (OSTI)

In this thesis, we demonstrate a functioning planar radio frequency, three-rod Paul Trap, loaded with Yb+ ions that have been photoionized from a source of neutral atoms, which were cooled in a magneto-optical trap. Planar ...

Shields, Brendan John

2006-01-01T23:59:59.000Z

335

Ensemble method to measure the potential energy of nanoparticles in an optical trap  

Science Journals Connector (OSTI)

A method is described for measuring the potential energy of nanoparticles in an optical trap by trapping an ensemble of particles with a focused laser beam. The force balance between...

Junio, Joseph; Ng, Jack; Cohen, Joel A; Lin, Zhifang; Ou-Yang, H Daniel

2011-01-01T23:59:59.000Z

336

Finite-geometry models of electric field noise from patch potentials in ion traps  

E-Print Network (OSTI)

We model electric field noise from fluctuating patch potentials on conducting surfaces by taking into account the finite geometry of the ion trap electrodes to gain insight into the origin of anomalous heating in ion traps. ...

Low, Guang Hao

337

Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study...  

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

Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Presentation given...

338

Quantum Energy Teleportation with Trapped Ions  

E-Print Network (OSTI)

We analyze a protocol of quantum energy teleportation that transports energy from the left edge of a linear ion crystal to the right edge by local operations and classical communication at a speed much higher than the speed of the phonon in the crystal. A probe qubit is strongly coupled with the phonon fluctuation in the ground state during short time and is projectively measured in order to get information about this phonon fluctuation. During the measurement process, phonons are excited by the time-dependent measurement interaction and energy of the excited phonons must be infused from outside the system. The obtained information is announced to the right edge of the crystal through a classical channel. Even though the phonons excited at the left edge do not arrive at the right edge yet when the information arrives at the right edge, we are able to soon extract energy from the ion at the right edge by using the announced information. Because the intermediate ions of the crystal are not excited during the ex...

Hotta, Masahiro

2009-01-01T23:59:59.000Z

339

Enumeration of Juvenile Salmonids in the Okanogan Basin Using Rotary Screw Traps, Performance Period: March 15, 2006 - July 15, 2006.  

SciTech Connect

The Colville Tribes identified the need for collecting baseline census data on the timing and abundance of juvenile salmonids in the Okanogan River basin for the purpose of documenting local fish populations, augmenting existing fishery data and assessing natural production trends of salmonids. This report documents and assesses the pilot year of rotary trap capture of salmonid smolts on the Okanogan River. The project is a component of the Colville Tribes Okanogan Basin Monitoring and Evaluation Program (OBMEP) which began in 2004. Trapping for outmigrating fish began on 14 March 2006 and continued through 11 July 2006. Anadromous forms of Oncorhynchus, including summer steelhead (O. mykiss), Chinook (O. tshawytscha), and sockeye (O. nerka), were targeted for this study; all have verified, natural production in the Okanogan basin. Both 8-ft and 5-ft rotary screw traps were deployed on the Okanogan River from the Highway 20 Bridge and typically fished during evening hours or 24 hours per day, depending upon trap position and discharge conditions. Juvenile Chinook salmon were the most abundant species trapped in 2006 (10,682 fry and 2,024 smolts), followed by sockeye (205 parr and 3,291 smolts) and steelhead (1 fry and 333 smolts). Of the trapped Chinook, all fry were wild origin and all but five of the smolts were hatchery-reared. All trapped sockeye were wild origin and 88% of the steelhead smolts were hatchery-reared. Mark-recapture experiments were conducted using Chinook fry and hatchery-reared steelhead smolts (sockeye were not used in 2006 because the peak of the juvenile migration occurred prior to the onset of the mark-recapture experiments). A total of 930 chinook fry were marked and released across eight separate release dates (numbers of marked Chinook fry released per day ranged from 34 to 290 fish). A total of 11 chinook fry were recaptured for an overall trap efficiency of 1.18%. A total of 710 hatchery-reared steelhead were marked and released across three separate release dates (numbers of steelhead released per day ranged from 100 to 500 fish). A total of 12 steelhead were recaptured for an overall trap efficiency of 1.69%. A pooled Peterson estimator with a Chapman modification was used to produce population estimates for wild Chinook fry and hatchery-reared steelhead based on the results of the mark-recapture experiments. The 2006 populations for Chinook and steelhead were estimated to be 381,554 (95% confidence intervals: 175,731-587,377) and 14,164 (6,999-21,330), respectively. The population estimates were based on the periods in which mark-recapture experiments were initialized through the end of the trapping season (10 May for steelhead and 1 June for Chinook).

Johnson, Peter N.; Rayton, Michael D.

2007-05-01T23:59:59.000Z

340

Exhaust Gas Fuel Reforming of Diesel Fuel by Nonthermal Arc Discharge for NOx Trap Regeneration Application  

Science Journals Connector (OSTI)

Exhaust Gas Fuel Reforming of Diesel Fuel by Nonthermal Arc Discharge for NOx Trap Regeneration Application ... It has been demonstrated that low current arc discharges are highly nonhomogenous. ... In the second case, which corresponds to the most favorable one, assuming (i) a 100 kW car engine thermal power (i.e., 40 kW mechanical power), (ii) that the plasma will treat only a small fraction of the exhaust gas (typically 3.5%), (iii) that the plasma will operate under a cycling operating mode, and (iv) an 80% efficiency for the onboard production of electricity from the car engine, one can estimate that the electric power needed to run the plasma will be around 2.2% of the engine power only during 12 s every 11 km (6.8 miles), that is, 12 s every 6 min assuming a 110 km·h?1 (68 mph) average car velocity. ...

Alexandre Lebouvier; Franc?ois Fresnet; Fre?de?ric Fabry; Vale?rie Boch; Vandad Rohani; Franc?ois Cauneau; Laurent Fulcheri

2011-02-03T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

An all-glass microfluidic cell for the ABEL trap: fabrication and Adam E. Cohen  

E-Print Network (OSTI)

An all-glass microfluidic cell for the ABEL trap: fabrication and modeling Adam E. Cohen Department trap is a microfluidic cell. In previous incarnations of the ABEL trap, the microfluidic cell microfluidic cell, made entirely out of glass. This new design significantly decreases the rate

Shapiro, Benjamin

342

How to assess light trapping structures versus a Lambertian Scatterer for solar cells ?  

E-Print Network (OSTI)

How to assess light trapping structures versus a Lambertian Scatterer for solar cells ? Christian trapping nanostructures for solar cells, which we call the light trapping efficiency (LTE). The LTE has in thin Si solar cells by diffuse back reflectors," Proceedings of the 15th IEEE Photovoltaic Specialists

343

Reduction of the trapping of positrons in dislocated single crystals of iron when charged with hydrogen  

SciTech Connect

The positron annihilation measurement was carried out with the pure iron single crystals deformed in various ways before and after hydrogen permeation. The positron trapping intensity was reduced more in the screw dislocation than in the edge dislocation by hydrogen charging. The trap occupancy by hydrogen was very close to the fraction of the reduction in positron trapping intensity.

Park, Y.K.; Waber, J.T.; Snead, C.L. Jr.

1985-01-01T23:59:59.000Z

344

Solar Cell Light Trapping beyond the Ray Optic Limit Dennis M. Callahan,* Jeremy N. Munday,  

E-Print Network (OSTI)

Solar Cell Light Trapping beyond the Ray Optic Limit Dennis M. Callahan,* Jeremy N. Munday: Photovoltaic cell, solar cell, local density of optical states (LDOS), light trapping, plasmonic, nanophotonic light trapping, as the solar cell absorber layer thickness is reduced, absorption is also reduced

Atwater, Harry

345

Towards trapped antihydrogen L.V. Jrgensen a,*, G. Andresen b  

E-Print Network (OSTI)

of antihydrogen physics. The next big step forward is expected to be the trapping of the formed antihydrogen atoms using a magnetic multipole trap. ALPHA is a new international project that started to take data in 2006 in a nested Penning trap [3]. After formation the antihydrogen was no longer bound by the electric

Wurtele, Jonathan

346

Electronic quantum effects mapped onto non-Born-Oppenheimer nuclear paths: Nonclassical surmounting over potential barriers and trapping above the transition states due to nonadiabatic path-branching  

SciTech Connect

We develop the path-branching representation for nonadiabatic electron wavepacket dynamics [T. Yonehara and K. Takatsuka, J. Chem. Phys. 132, 244102 (2010)] so as to treat dynamics in an energy range comparable to the barrier height of adiabatic potential energy curves. With this representation two characteristic chemical reaction dynamics are studied, in which an incident nuclear wavepacket encounters a potential barrier, on top of which lies another nonadiabatically coupled adiabatic potential curve: (1) Dynamics of initial paths coming into the nonadiabatic interaction region with energy lower than the barrier height. They branch into two pieces (and repeat branching subsequently), the upper counterparts of which can penetrate into a classically inaccessible high energy region and eventually branch back to the product region on the ground state curve. This is so to say surmounting the potential barrier via nonadiabatically coupled excited state, and phenomenologically looks like the so-called deep tunneling. (2) Dynamics of classical paths whose initial energies are a little higher than the barrier but may be lower than the bottom of the excited state. They can undergo branching and some of those components are trapped on top of the potential barrier, being followed by the population decay down to the lower state flowing both to product and reactant sites. Such expectations arising from the path-branching representation are numerically confirmed with full quantum mechanical wavepacket dynamics. This phenomenon may be experimentally observed as time-delayed pulses of wavepacket trains.

Yamamoto, Kentaro, E-mail: kyamamoto@mns2.c.u-tokyo.ac.jp; Takatsuka, Kazuo, E-mail: kaztak@mns2.c.u-tokyo.ac.jp [Department of Basic Science, The University of Tokyo, Komaba, 153-8902 Tokyo (Japan)] [Department of Basic Science, The University of Tokyo, Komaba, 153-8902 Tokyo (Japan)

2014-03-28T23:59:59.000Z

347

Electron beam driven alkali metal atom source for loading a magneto-optical trap in a cryogenic environment  

E-Print Network (OSTI)

We present a versatile and compact electron beam driven source for alkali metal atoms, which can be implemented in cryostats. With a heat load of less than 10mW, the heat dissipation normalized to the atoms loaded into the magneto-optical Trap (MOT), is about a factor 1000 smaller than for a typical alkali metal dispenser. The measured linear scaling of the MOT loading rate with electron current observed in the experiments, indicates that electron stimulated desorption is the corresponding mechanism to release the atoms.

S. Haslinger; R. Amsuess; Ch. Koller; C. Hufnagel; N. Lippok; J. Majer; J. Verdu; S. Schneider; J. Schmiedmayer

2010-03-26T23:59:59.000Z

348

Features of conduction mechanisms in Si/oligo-{beta}-naphthol/metal heterostructures  

SciTech Connect

Conduction mechanisms in Si-polymer-metal heterostructures with oligo-{beta}-naphthol as a wide band-gap polymer have been studied. The results obtained are explained within the models of hopping transport via trap levels, Schottky emission, and field tunneling emission. Different charge transport mechanisms operate in different temperature ranges and under different electric fields.

Hasannli, Sh. M., E-mail: Hasanli_sh@rambler.ru; Mursakulov, N. N.; Samedova, U. F.; Abdulzade, N. N.; Mamedov, B. A. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Guseynov, R. K. [Ganja State University (Azerbaijan)

2010-07-15T23:59:59.000Z

349

A comparison study of gravid and under house CO2 mosquito traps in Harris County, Texas  

E-Print Network (OSTI)

Traps in Harris County, Texas. (May 2008) Stephanie Lyn White, B.S.; B.S., Texas A&M University Chair of Advisory Committee: Dr. Michael P. Ward Harris County Mosquito Control Division (HCMCD) is responsible for surveillance of mosquito species...2 traps for WNV and SLE virus surveillance. Adjusting for the week of collection, results suggest that Gravid traps caught significantly (P = 0.009) more mosquitoes (mean = 23.134 per trap) in the study area than Underhouse traps (mean = 3...

White, Stephanie Lyn

2008-10-10T23:59:59.000Z

350

A Toy Model Study of Decay Trapping | Superconducting Magnet Division  

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

A Toy Model Study of Decay Trapping, reported by Brett Parker A Toy Model Study of Decay Trapping, reported by Brett Parker Introduction A group from the BNL Superconducting Magnet Division is looking at various options for dipole magnets which would be suitable for use in a muon storage ring that is used as a neutrino factory. Since the useful neutrino beams from a neutrino factory come from straight sections it is desirable to minimize the rings arc circumference, in relation to straight section length, in order to ensure that the fraction of muons which decay in the straight section is as large as possible. Therefore superconducting magnets, with higher B-fields and smaller bend radii, are reasonable to consider for this application. Unfortunately the decay electrons generated along with the neutrinos carry on average about a third of the original

351

A bosonic Josephson junction controlled by a single trapped ion  

E-Print Network (OSTI)

We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a single $^{87}$Rb atom and a small Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate inter-well coupling rates reaching hundreds of Hz, while the state dependence amounts to tens of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The analysis shows that it is possible to induce either the self-trapping or the tunneling regime, depending on the internal state of the ion. This enables the generation of large scale ion-atomic wavepacket entanglement within current technology.

R. Gerritsma; A. Negretti; H. Doerk; Z. Idziaszek; T. Calarco; F. Schmidt-Kaler

2012-07-25T23:59:59.000Z

352

Electromagnetic two-dimensional analysis of trapped-ion eigenmodes  

SciTech Connect

A two-dimensional electromagnetic analysis of the trapped-ion instability for the tokamak case with ..beta.. not equal to 0 has been made, based on previous work in the electrostatic limit. The quasineutrality condition and the component of Ampere's law along the equilibrium magnetic field are solved for the perturbed electrostatic potential and the component of the perturbed vector potential along the equilibrium magnetic field. The general integro-differential equations are converted into a matrix eigenvalue-eigenfunction problem by expanding in cubic B-spline finite elements in the minor radius and in Fourier harmonics in the poloidal angle. A model MHD equilibrium with circular, concentric magnetic surfaces and large aspect ratio is used which is consistent with our assemption that B << 1. The effect on the trapped-ion mode of including these electromagnetic extensions to the calculation is considered, and the temperature (and ..beta..) scaling of the mode frequency is shown and discussed.

Kim, D.; Rewoldt, G.

1984-11-01T23:59:59.000Z

353

Photoionization of strontium for trapped-ion quantum information processing  

E-Print Network (OSTI)

We report a demonstration of simple and effective loading of strontium ions into a linear radio frequency Paul trap using photoionization. The ionization pathway is 5s2 1S0 -- 5s5p 1P1 -- 5p2 1D2, and the 5p2 1D2 final state is auto-ionizing. Both transitions are driven using diode lasers: a grating-stabilized 922 nm diode doubled in a single pass through potassium niobate to 461 nm and a bare diode at 405 nm. Using this technique, we have reduced the background pressure during the ion loading process by a factor of 2 compared to the conventional technique of electron bombardment. Initial ion temperatures are low enough that the ions immediately form crystals. It is also possible to observe the trapping region with a CCD camera during ion creation, allowing specific ion number loading with high probability.

K. Vant; J. Chiaverini; W. Lybarger; D. J. Berkeland

2006-07-07T23:59:59.000Z

354

Measurement-Induced Vibrational Dynamics of a Trapped Ion  

Science Journals Connector (OSTI)

Excitation spectra of an individual trapped 138Ba+ ion show sidebands of radial and axial ion vibration in the trap. The second-order sidebands involving radial and axial vibrations would allow swapping these vibrational states; they represent an inverse Raman effect with the role of electronic and vibrational excitation interchanged. Deexcitation sidebands differ from excitation sidebands as the vibrational distribution in the D5/2 level is modified by the ion being reduced to this level in null observations of resonance light. Delayed deexcitation goes along with stochastic cooling that makes the ion collapse into the Fock state |n=1?. Sideband modulation is identified as stroboscopic detection of the light-induced nutation on a vibrational transition with ?n=±1.

B. Appasamy; Y. Stalgies; P. E. Toschek

1998-03-30T23:59:59.000Z

355

Engineering two-mode interactions in ion traps  

E-Print Network (OSTI)

We describe how two vibrational degrees of freedom of a single trapped ion can be coupled through the action of suitably-chosen laser excitation. We concentrate on a two-dimensional ion trap with dissimilar vibrational frequencies in the x- and y-directions of motion, and derive from first principles a variety of quantized two-mode couplings, concentrating on a linear coupling which takes excitations from one mode to another. We demonstrate how this can result in a state rotation, in which it is possible to transfer the motional state of the ion from say the x-direction to the y-direction without prior knowledge of that motional state.

J. Steinbach; J. Twamley; P. L. Knight

1997-08-04T23:59:59.000Z

356

Engineering superpositions of displaced number states of a trapped ion  

E-Print Network (OSTI)

We present a protocol that permits the generation of a subtle with superposition with 2^(l+1) displaced number states on a circle in phase space as target state for the center-of-mass motion of a trapped ion. Through a sequence of 'l' cycles involving the application of laser pulses and no-fluorescence measurements, explicit expressions for the total duration of laser pulses employed in the sequence and probability of getting the ion in the upper electronic state during the 'l' cycles are obtained and analyzed in detail. Furthermore, assuming that the effective relaxation process of a trapped ion can be described in the framework of the standard master equation for the damped harmonic oscillator, we investigate the degradation of the quantum interference effects inherent to superpositions via Wigner function.

Marcelo A. Marchiolli; Wagner D. Jose

2004-04-05T23:59:59.000Z

357

Wolf Trap, Virginia: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Trap, Virginia: Energy Resources Trap, Virginia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 38.9398329°, -77.286094° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.9398329,"lon":-77.286094,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

358

Isoelectric Trapping and Mass Spectrometry: Tools for Proteomics  

E-Print Network (OSTI)

ISOELECTRIC TRAPPING AND MASS SPECTROMETRY: TOOLS FOR PROTEOMICS A Dissertation by STEPHANIE MARIE COLOGNA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, David H. Russell Committee Members, Paul S. Cremer Arul Jayaraman Gyula Vigh Head of Department, David H...

Cologna, Stephanie Marie

2012-02-14T23:59:59.000Z

359

Adiabatic trapping in coupled kinetic Alfven-acoustic waves  

SciTech Connect

In the present work, we have discussed the effects of adiabatic trapping of electrons on obliquely propagating Alfven waves in a low {beta} plasma. Using the two potential theory and employing the Sagdeev potential approach, we have investigated the existence of arbitrary amplitude coupled kinetic Alfven-acoustic solitary waves in both the sub and super Alfvenic cases. The results obtained have been analyzed and presented graphically and can be applied to regions of space where the low {beta} assumption holds true.

Shah, H. A.; Ali, Z. [Department of Physics, G.C. University, 54000 Lahore (Pakistan); Masood, W. [COMSATS, Institute of Information Technology, Park Road, Chak Shahzad, Islamabad 44000 (Pakistan); National Centre for Physics (NCP), Shahdara Valley Road, 44000 Islamabad (Pakistan); Theoretical Plasma Physics Division, P. O. Nilore, Islamabad (Pakistan)

2013-03-15T23:59:59.000Z

360

Phase-dependent coherent population trapping and optical switching  

SciTech Connect

We propose a scheme for achieving phase-dependent coherent population trapping, showing that both the dark state of the atoms and light propagation dynamics depend on the relative phase of the fields. The atomic coherence prepared via adiabatic process plays a key role in the interaction of light with matter. And an optical switching based on the phase-controlled quantum interference is implemented, which may have potential application in high-speed optical communications and quantum information systems.

Kou, J. [College of Physics, Jilin University, Changchun 130023 (China); Quantum Engineering Center, Beijing Institute of Control Device, Beijing 100854 (China); Wan, R. G.; Kang, Z. H.; Jiang, L.; Wang, L.; Jiang, Y.; Gao, J. Y. [College of Physics, Jilin University, Changchun 130023 (China)

2011-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Fabrication and heating rate study of microscopic surface electrode ion traps  

E-Print Network (OSTI)

We report heating rate measurements in a microfabricated gold-on-sapphire surface electrode ion trap with trapping height of approximately 240 micron. Using the Doppler recooling method, we characterize the trap heating rates over an extended region of the trap. The noise spectral density of the trap falls in the range of noise spectra reported in ion traps at room temperature. We find that during the first months of operation the heating rates increase by approximately one order of magnitude. The increase in heating rates is largest in the ion loading region of the trap, providing a strong hint that surface contamination plays a major role for excessive heating rates. We discuss data found in the literature and possible relation of anomalous heating to sources of noise and dissipation in other systems, namely impurity atoms adsorbed on metal surfaces and amorphous dielectrics.

N. Daniilidis; S. Narayanan; S. A. Möller; R. Clark; T. E. Lee; P. J. Leek; A. Wallraff; St. Schulz; F. Schmidt-Kaler; H. Häffner

2010-09-15T23:59:59.000Z

362

Cavity-enhanced optical bottle beam as a mechanical amplifier  

Science Journals Connector (OSTI)

We analyze the resonant cavity enhancement of a hollow “optical bottle beam” for the dipole-force trapping of dark-field-seeking species. We first improve upon the basic bottle beam by adding further Laguerre-Gaussian components to deepen the confining potential. Each of these components itself corresponds to a superposition of transverse cavity modes, which are then enhanced simultaneously in a confocal cavity to produce a deep optical trap needing only a modest incident power. The response of the trapping field to displacement of the cavity mirrors offers an unusual form of mechanical amplifier in which the Gouy phase shift produces an optical Vernier scale between the Laguerre-Gaussian beam components.

Tim Freegarde and Kishan Dholakia

2002-07-30T23:59:59.000Z

363

Mechanical memory  

DOE Patents (OSTI)

A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Albuquerque, NM); Baker, Michael S. (Albuquerque, NM)

2006-05-16T23:59:59.000Z

364

Mechanical memory  

DOE Patents (OSTI)

A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Alburquerque, NM); Baker, Michael S. (Albuquerque, NM)

2006-08-15T23:59:59.000Z

365

New designs in reconstructing the mechanical equipment of hydroelectric stations  

Science Journals Connector (OSTI)

1. Reliable operation of mechanical equipment can be assured, provided timely conduction of repairs and reconstr...

S. V. Leeson

1996-03-01T23:59:59.000Z

366

Coherent oscillations between two weakly coupled Bose-Einstein Condensates: Josephson effects, $?$-oscillations, and macroscopic quantum self trapping  

E-Print Network (OSTI)

We discuss the coherent atomic oscillations between two weakly coupled Bose-Einstein condensates. The weak link is provided by a laser barrier in a (possibly asymmetric) double-well trap or by Raman coupling between two condensates in different hyperfine levels. The Boson Josephson Junction (BJJ) dynamics is described by the two-mode non-linear Gross-Pitaevskii equation, that is solved analytically in terms of elliptic functions. The BJJ, being a $neutral$, isolated system, allows the investigations of new dynamical regimes for the phase difference across the junction and for the population imbalance, that are not accessible with Superconductor Josephson Junctions (SJJ). These include oscillations with either, or both of the following properties: 1) the time-averaged value of the phase is equal to $\\pi$ ($\\pi-phase$ oscillations); 2) the average population imbalance is nonzero, in states with ``macroscopic quantum self-trapping'' (MQST). The (non-sinusoidal) generalization of the SJJ `ac' and `plasma' oscillations and the Shapiro resonance can also be observed. We predict the collapse of experimental data (corresponding to different trap geometries and total number of condensate atoms) onto a single universal curve, for the inverse period of oscillations. Analogies with Josephson oscillations between two weakly coupled reservoirs of $^3$He-B and the internal Josephson effect in $^3$He-A are also discussed.

S. Raghavan; A. Smerzi; S. Fantoni; S. R. Shenoy

1997-06-23T23:59:59.000Z

367

From pre-salt sources to post-salt traps: A specific petroleum system in Congo coastal basin  

SciTech Connect

The Bas Congo basin extends from Gabon to Angola and is a prolific oil province where both pre-salt and post salt sources and reservoirs have been found. In the northern part of the basin referred to as the Congo coastal basin, the proven petroleum system is more specific: mature source rocks are found only in pre-salt series whereas by contrast 99 % proven hydrocarbon reserves am located in post-salt traps. Such a system is controlled by the following factors: Source rocks are mostly organic rich shales deposited in a restricted environment developed in a rift prior to the Atlantic Ocean opening; Migration from pre-salt sources to post-salt traps is finalized by local discontinuities of the regional salt layer acting otherwise as a tight seal; Post-salt reservoirs are either carbonates or sands desposited in the evolutive shelf margin developped during Upper Cretaceous; Geometric traps are linked to salt tectonics (mostly turtle-shaped structures); Regional shaly seals are related to transgressive shales best developped during high rise sea level time interval. Stratigraphically, the age of hydrocarbon fields trends are younger and younger from West to East: lower Albian in Nkossa, Upper Albian and lower Cenomanian in Likouala, Yanga, Sendji, Upper Cenomanian in Tchibouela, Turonian in Tchendo, Turanian and Senonian in Emeraude.

Vernet, R.

1995-08-01T23:59:59.000Z

368

Formation of molecular ions by radiative association of cold trapped atoms and ions  

E-Print Network (OSTI)

Radiative emission during cold collisions between trapped laser-cooled Rb atoms and alkaline-earth ions (Ca + , Sr + , Ba +) and Yb + are studied theoretically, using accurate effective-core-potential based quantum chemistry calculations of potential energy curves and transition dipole moments of the related molecular ions. Radiative association of molecular ions is predicted to occur for all systems with a cross section two to ten times larger than the radiative charge transfer one. Partial and total rate constants are also calculated and compared to available experiments. Narrow shape resonances are expected, which could be detectable at low temperature with an experimental resolution at the limit of the present standards. Vibrational distributions are also calculated, showing that the final molecular ions are not created in their ground state level.

Silva, Humberto Da; Aymar, Mireille; Dulieu, Olivier

2015-01-01T23:59:59.000Z

369

Precision lifetime measurements of a single trapped ion with ultrafast laser pulses  

E-Print Network (OSTI)

We report precision measurements of the excited state lifetime of the $5p$ $^2P_{1/2}$ and $5p$ $^2P_{3/2}$ levels of a single trapped Cd$^+$ ion. The ion is excited with picosecond laser pulses from a mode-locked laser and the distribution of arrival times of spontaneously emitted photons is recorded. The resulting lifetimes are 3.148 $\\pm$ 0.011 ns and 2.647 $\\pm$ 0.010 ns for $^2P_{1/2}$ and $^2P_{3/2}$ respectively. With a total uncertainty of under 0.4%, these are among the most precise measurements of any atomic state lifetimes to date.

D. L. Moehring; B. B. Blinov; D. W. Gidley; R. N. Kohn Jr.; M. J. Madsen; T. D. Sanderson; R. S. Vallery; C. Monroe

2005-05-15T23:59:59.000Z

370

Plasmonic Light Trapping in an Ultrathin Photovoltaic Layer with Film-Coupled Metamaterial Structures  

E-Print Network (OSTI)

A film-coupled metamaterial structure is numerically investigated for enhancing the light absorption in an ultrathin photovoltaic layer of crystalline gallium arsenide (GaAs). The top subwavelength concave grating and the bottom metallic film could not only effectively trap light with the help of wave interference and magnetic resonance effects excited above the bandgap, but also practically serve as electrical contacts for photon-generated charge collection. The energy absorbed by the active layer is greatly enhanced in the film-coupled metamaterial structure, resulting in significant enhancement on the short-circuit current density by three times over a free-standing GaAs layer at the same thickness. The results would facilitate the development of next-generation ultrathin solar cells with lower cost and higher efficiency.

Wang, Hao

2014-01-01T23:59:59.000Z

371

Ground-state cooling of a trapped ion using long-wavelength radiation  

E-Print Network (OSTI)

We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

Weidt, S; Webster, S C; Standing, E D; Rodriguez, A; Webb, A E; Lekitsch, B; Hensinger, W K

2015-01-01T23:59:59.000Z

372

Ground-state cooling of a trapped ion using long-wavelength radiation  

E-Print Network (OSTI)

We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

S. Weidt; J. Randall; S. C. Webster; E. D. Standing; A. Rodriguez; A. E. Webb; B. Lekitsch; W. K. Hensinger

2015-01-07T23:59:59.000Z

373

Spectroscopy of Charge Carriers and Traps in Field-Doped Organic Semiconductors  

SciTech Connect

This research project aims to achieve quantitative and molecular level understanding of charge carriers and traps in field-doped organic semiconductors via in situ optical absorption spectroscopy, in conjunction with time-resolved electrical measurements. During the funding period, we have made major progress in three general areas: (1) probed charge injection at the interface between a polymeric semiconductor and a polymer electrolyte dielectric and developed a thermodynamic model to quantitatively describe the transition from electrostatic to electrochemical doping; (2) developed vibrational Stark effect to probe electric field at buried organic semiconductor interfaces; (3) used displacement current measurement (DCM) to study charge transport at organic/dielectric interfaces and charge injection at metal/organic interfaces.

Zhu, Xiaoyang; Frisbie, C Daniel

2012-08-13T23:59:59.000Z

374

Ground state cooling, quantum state engineering and study of decoherence of ions in Paul traps  

E-Print Network (OSTI)

We investigate single ions of $^{40}Ca^+$ in Paul traps for quantum information processing. Superpositions of the S$_{1/2}$ electronic ground state and the metastable D$_{5/2}$ state are used to implement a qubit. Laser light on the S$_{1/2} \\leftrightarrow$ D$_{5/2}$ transition is used for the manipulation of the ion's quantum state. We apply sideband cooling to the ion and reach the ground state of vibration with up to 99.9% probability. Starting from this Fock state $|n=0>$, we demonstrate coherent quantum state manipulation. A large number of Rabi oscillations and a ms-coherence time is observed. Motional heating is measured to be as low as one vibrational quantum in 190 ms. We also report on ground state cooling of two ions.

F. Schmidt-Kaler; Ch. Roos; H. C. Naegerl; H. Rohde; S. Gulde; A. Mundt; M. Lederbauer; G. Thalhammer; Th. Zeiger; P. Barton; L. Hornekaer; G. Reymond; D. Leibfried; J. Eschner; R. Blatt

2000-03-21T23:59:59.000Z

375

Formation of molecular ions by radiative association of cold trapped atoms and ions  

E-Print Network (OSTI)

Radiative emission during cold collisions between trapped laser-cooled Rb atoms and alkaline-earth ions (Ca + , Sr + , Ba +) and Yb + are studied theoretically, using accurate effective-core-potential based quantum chemistry calculations of potential energy curves and transition dipole moments of the related molecular ions. Radiative association of molecular ions is predicted to occur for all systems with a cross section two to ten times larger than the radiative charge transfer one. Partial and total rate constants are also calculated and compared to available experiments. Narrow shape resonances are expected, which could be detectable at low temperature with an experimental resolution at the limit of the present standards. Vibrational distributions are also calculated, showing that the final molecular ions are not created in their ground state level.

Humberto Da Silva Jr; Maurice Raoult; Mireille Aymar; Olivier Dulieu

2015-01-26T23:59:59.000Z

376

Long-time evolution of sequestered CO$_2$ in porous media  

E-Print Network (OSTI)

CO$_2$ sequestration in subsurface reservoirs is important for limiting atmospheric CO$_2$ concentrations. However, a complete physical picture able to predict the structure developing within the porous medium is lacking. We investigate theoretically reactive transport in the long-time evolution of carbon in the brine-rock environment. As CO$_2$ is injected into a brine-rock environment, a carbonate-rich region is created amid brine. Within the carbonate-rich region minerals dissolve and migrate from regions of high concentration to low concentration, along with other dissolved carbonate species. This causes mineral precipitation at the interface between the two regions. We argue that precipitation in a small layer reduces diffusivity, and eventually causes mechanical trapping of the CO$_2$. Consequently, only a small fraction of the CO$_2$ is converted to solid mineral; the remainder either dissolves in water or is trapped in its original form. We also study the case of a pure CO$_2$ bubble surrounded by bri...

Cohen, Yossi

2014-01-01T23:59:59.000Z

377

Computational mechanics  

SciTech Connect

The Computational Mechanics thrust area sponsors research into the underlying solid, structural and fluid mechanics and heat transfer necessary for the development of state-of-the-art general purpose computational software. The scale of computational capability spans office workstations, departmental computer servers, and Cray-class supercomputers. The DYNA, NIKE, and TOPAZ codes have achieved world fame through our broad collaborators program, in addition to their strong support of on-going Lawrence Livermore National Laboratory (LLNL) programs. Several technology transfer initiatives have been based on these established codes, teaming LLNL analysts and researchers with counterparts in industry, extending code capability to specific industrial interests of casting, metalforming, and automobile crash dynamics. The next-generation solid/structural mechanics code, ParaDyn, is targeted toward massively parallel computers, which will extend performance from gigaflop to teraflop power. Our work for FY-92 is described in the following eight articles: (1) Solution Strategies: New Approaches for Strongly Nonlinear Quasistatic Problems Using DYNA3D; (2) Enhanced Enforcement of Mechanical Contact: The Method of Augmented Lagrangians; (3) ParaDyn: New Generation Solid/Structural Mechanics Codes for Massively Parallel Processors; (4) Composite Damage Modeling; (5) HYDRA: A Parallel/Vector Flow Solver for Three-Dimensional, Transient, Incompressible Viscous How; (6) Development and Testing of the TRIM3D Radiation Heat Transfer Code; (7) A Methodology for Calculating the Seismic Response of Critical Structures; and (8) Reinforced Concrete Damage Modeling.

Goudreau, G.L.

1993-03-01T23:59:59.000Z

378

Simulation of dust streaming in toroidal traps: Stationary flows  

SciTech Connect

Molecular-dynamic simulations were performed to study dust motion in a toroidal trap under the influence of the ion drag force driven by a Hall motion of the ions in E x B direction, gravity, inter-particle forces, and friction with the neutral gas. This article is focused on the inhomogeneous stationary streaming motion. Depending on the strength of friction, the spontaneous formation of a stationary shock or a spatial bifurcation into a fast flow and a slow vortex flow is observed. In the quiescent streaming region, the particle flow features a shell structure which undergoes a structural phase transition along the flow direction.

Reichstein, Torben; Piel, Alexander [IEAP, Christian-Albrechts-Universitaet, D-24098 Kiel (Germany)

2011-08-15T23:59:59.000Z

379

Dipole trapped spheromak in a prolate flux conserver  

Science Journals Connector (OSTI)

This paper reports the observation and characterization of a spheromak formed in the Swarthmore Spheromak Experiment (SSX [M. R. Brown Phys. Plasmas6 1717 (1999)]) and trapped in a simple dipole magnetic field. The spheromak is studied in a prolate (tilt unstable) 0.4 m diameter 0.6 m length copper flux conserver in SSX. This plasma does not tilt despite the prolate flux conserver. The spheromak is characterized by a suite of magnetic probe arrays for magnetic structure B ( r t ) ion Doppler spectroscopy for T i and flow and interferometry for n e . Three-dimensional magnetohydrodynamics simulations of this configuration verify its gross sta-bility.

M. R. Brown; C. D. Cothran; J. Fung; M. Chang; J. Horwitz; M. J. Schaffer; J. Leuer; E. V. Belova

2006-01-01T23:59:59.000Z

380

Effect of Trapped Energetic Particles on the Resistive Wall Mode  

SciTech Connect

A stability analysis for the resistive wall mode is studied in the presence of trapped energetic particles (EPs). When the EPs' beta exceeds a critical value, a fishbonelike bursting mode (FLM) with an external kink eigenstructure can exist. This offers the first analytic interpretation of the experimental observations [Phys. Rev. Lett. 103, 045001 (2009)]. The mode-particle resonances for the FLM and the q=1 fishbone occur in different regimes of the precession frequency of EPs. In certain ranges of the plasma rotation speed and the EPs' beta, a mode conversion can occur between the resistive wall mode and FLM.

Hao, G. Z.; Wang, A. K.; Qiu, X. M. [Southwestern Institute of Physics, Post Office Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Prospects for cooling and trapping rotationally hot molecules  

Science Journals Connector (OSTI)

Cold collisions involving highly rotationally excited diatomic molecules are investigated. As the translational energy is lowered, the total inelastic cross section decreases sharply for specific channels where quasiresonant transitions are no longer energetically allowed. Rate coefficients are given for collisional quenching of rotationally excited H2,D2,T2, and O2 at zero temperature. The specific rotational states that are stable against collisional relaxation would be interesting prospects for cooling and trapping. The application of collisional cooling methods together with recently developed schemes for producing rotationally hot molecules may allow high densities of ultracold “super rotors” to be achieved.

R. C. Forrey

2002-08-27T23:59:59.000Z

382

Stabilization of the resistive wall mode instability by trapped energetic particles  

SciTech Connect

A theoretical model for investigating the effect of the trapped energetic particles (EPs) on the resistive wall mode (RWM) instability is proposed. The results demonstrate that the trapped EPs have a dramatic stabilizing effect on the RWM because of resonant interaction between the mode and the magnetic precession drift motion of the trapped EPs. The results also show that the effect of the trapped EPs depends on the wall position. In addition, the stabilizing effect becomes stronger when the plasma rotation is taken into account. For sufficiently fast plasma rotation, the trapped EPs can lead to the complete stabilization of the RWM. Furthermore, the trapped EPs can induce a finite real frequency of the RWM in the absence of plasma rotation.

Hao, G. Z.; Wang, A. K.; Jiang, H. B.; Lu, Gaimin; He, H. D.; Qiu, X. M. [Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

2011-03-15T23:59:59.000Z

383

Destruction of attractive bosonic cloud due to high spatial coherence in tight trap  

SciTech Connect

We study coherence of a trapped bosonic cloud with attractive finite-range interaction in a tight harmonic trap. One-body density and pair-distribution function in the ground state for different trap sizes are calculated. We also calculate healing length and the correlation length which signify the presence of high spatial coherence in a very tight trap leading to the destruction of the condensate for a fixed particle number. This is in marked variance with the usual collapse of the attractive metastable condensate when N>N{sub cr}. Thus we investigate the critical frequency and critical size of the trap for the existence of attractive Bose-Einstein condensation. The finite-range interaction gives a nonlocal effect in the effective many-body potential, and we observe a high-density stable branch besides the known metastable branch. Moreover, the new branch shows universal behavior even in the very tight trap.

Biswas, Anindya; Das, Tapan Kumar [Department of Physics, University of Calcutta, 92 A.P.C. Road, Kolkata 700009 (India); Chakrabarti, Barnali [Instituto de Fisica, Universidade of Sao Paulo, CP 66318, 05315-970 Sao Paulo-SP (Brazil); Department of Physics, Lady Brabourne College, P1/2 Surawardi Avenue, Kolkata 700017 (India); Salasnich, Luca [Dipartimento di Fisica ''Galileo Galilei'' and CNISM, Universita di Padova, Via Marzolo 8, IT-35122 Padova (Italy)

2011-10-15T23:59:59.000Z

384

Mechanical Vibration  

Science Journals Connector (OSTI)

... THE suppression and control of mechanical vibration have assumed great importance in engineering. One consequence of this is that the number ... degree of emphasis is placed on transient oscillation (in addition to steady-State and free vibration). The treatment of this topic is based mainly on phase-plane constructions and it ...

R. E. D. BISHOP

1958-12-06T23:59:59.000Z

385

Parametric self pulsing in a quantum opto-mechanical system  

E-Print Network (OSTI)

We describe an opto-mechanical system in which the coupling between optical and mechanical degrees of freedom takes the form of a fully quantised third-order parametric interaction. Two physical realisations are proposed: a harmonically trapped atom in a standing wave and the `membrane in the middle' model. The dominant resonant interaction corresponds to a stimulated Raman process in which two phonons are converted into a single cavity photon. We show that this system can exhibit a stable limit cycle in which energy is periodically exchanged between optical and mechanical degrees of freedom. This is equivalently described as a parametric self-pulsing.

Holmes, C A

2009-01-01T23:59:59.000Z

386

Fast shuttling of a trapped ion in the presence of noise  

E-Print Network (OSTI)

We theoretically investigate the motional excitation of a single ion caused by spring-constant and position uctuations of a harmonic trap during trap shuttling processes. A detailed study of the sensitivity on noise for several transport protocols and noise spectra is provided. The e?ect of slow spring-constant drifts is also analyzed. Trap trajectories that minimize the excitation are designed combining invariant-based inverse engineering, perturbation theory, and optimal control.

Xiao-Jing Lu; J. G. Muga; Xi Chen; U. G. Poschinger; F. Schmidt-Kaler; A. Ruschhaupt

2014-04-16T23:59:59.000Z

387

Light trapping and near-unity solar absorption in a three-dimensional photonic-crystal  

E-Print Network (OSTI)

Light trapping and near-unity solar absorption in a three-dimensional photonic-crystal Ping Kuang,1 opens up a new door for light trapping and near-unity solar absorption over broad s and wide angles://dx.doi.org/10.1364/OL.38.004200 There is a great deal of interest in efficient light trapping in thin film solar

John, Sajeev

388

Efficient Collection of 221Fr into a Vapor Cell Magneto-optical Trap  

Science Journals Connector (OSTI)

We have efficiently loaded a vapor cell magneto-optical trap from an orthotropic source of 221Fr with a trapping efficiency of 56(10)%. A novel detection scheme allowed us to measure 900 trapped atoms with a signal to noise ratio of ?60 in 1 sec. We have measured the energies and the hyperfine constants of the 7P1/22 and 7P3/22 states.

Z.-T. Lu; K. L. Corwin; K. R. Vogel; C. E. Wieman; T. P. Dinneen; J. Maddi; Harvey Gould

1997-08-11T23:59:59.000Z

389

Single-ion nonlinear mechanical oscillator  

SciTech Connect

We study the steady-state motion of a single trapped ion oscillator driven to the nonlinear regime. Damping is achieved via Doppler laser cooling. The ion motion is found to be well described by the Duffing oscillator model with an additional nonlinear damping term. We demonstrate here the unique ability of tuning both the linear as well as the nonlinear damping coefficients by controlling the laser-cooling parameters. Our observations pave the way for the investigation of nonlinear dynamics on the quantum-to-classical interface as well as mechanical noise squeezing in laser-cooling dynamics.

Akerman, N.; Kotler, S.; Glickman, Y.; Dallal, Y.; Keselman, A.; Ozeri, R. [Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel)

2010-12-15T23:59:59.000Z

390

Variation of carrier concentration and interface trap density in 8MeV electron irradiated c-Si solar cells  

SciTech Connect

The capacitance and conductance measurements were carried out for c-Si solar cells, irradiated with 8 MeV electrons with doses ranging from 5kGy – 100kGy in order to investigate the anomalous degradation of the cells in the radiation harsh environments. Capacitance – Voltage measurements indicate that there is a slight reduction in the carrier concentration upon electron irradiation due to the creation of radiation induced defects. The conductance measurement results reveal that the interface state densities and the trap time constant increases with electron dose due to displacement damages in c-Si solar cells.

Bhat, Sathyanarayana, E-mail: asharao76@gmail.com; Rao, Asha, E-mail: asharao76@gmail.com [Department of Physics, Mangalore Institute of Technology and Engineering, Moodabidri, Mangalore-574225 (India); Krishnan, Sheeja [Department of Physics, Sri Devi Institute of Technology, Kenjar, Mangalore-574142 (India); Sanjeev, Ganesh [Microtron Centre, Department of Physics, Mangalore University, Mangalagangothri-574199 (India); Suresh, E. P. [Solar Panel Division, ISRO Satellite Centre, Bangalore-560017 (India)

2014-04-24T23:59:59.000Z

391

Two-stream cyclotron radiative instabilities due to the marginally mirror-trapped fraction for fustion alphas in tokamaks  

SciTech Connect

It is shown here that the marginally mirror-trapped fraction of the newly-born fusion alpha particles in the deuterium-tritium (DT) reaction dominated tokamak plasmas can induce a two-stream cyclotron radiative instability for the fast Alfven waves propagating near the harmonics of the alpha particle cyclotron frequency {omega}{sub c{alpha}}. This can explain both the experimentally observed time behavior and the spatially localized origin of the fusion product ion cyclotron emission (ICE) in TFTR at frequencies {omega} {approx} m{omega}{sub c{alpha}}.

Arunasalam, V.

1995-07-01T23:59:59.000Z

392

E-Print Network 3.0 - antiproton trap hipat Sample Search Results  

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

of - Department of Physics, Non-Neutral Plasma Project Collection: Plasma Physics and Fusion 12 Cold Trapped Positrons and Progress to Cold Antihydrogen Summary: over a wide...

393

Synergies of High-Efficiency Clean Combustion and Lean NOx Trap...  

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

Combustion and Lean NOx Trap Catalysts investigation of potential synergies of low emission advanced combustion techniques and advanced lean exhaust catalytic aftertreatment....

394

Technological assessment of light-trapping technology for thin-film Si solar cell.  

E-Print Network (OSTI)

??The proposed light trapping technology of Distributed Bragg Reflector (DBR) with Diffraction Grating (DG) and Anti-Reflection Coating (ARC) for thin film Si solar cell was… (more)

Susantyoko, Rahmat Agung

2009-01-01T23:59:59.000Z

395

E-Print Network 3.0 - ap-8 trapped proton Sample Search Results  

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

J. Bebek, Armin Karcher, William F. Kolbe, Natalie A. Roe, Summary: Charge trap identification for proton-irradiated p+ channel CCDs Nick J. Mostek, Christopher J... , we...

396

Coherent population trapping on the sodium D1 line in high magnetic fields  

Science Journals Connector (OSTI)

We consider the coherent-population-trapping (CPT) phenomenon in a sodium atomic vapor. The experiment leading to the first observation of CPT is revisited with an improved...

Höller, R; Renzoni, F; Windholz, L; Xu, J H

1997-01-01T23:59:59.000Z

397

Compact, Rapid Cell Deformability Measurements Using Diode Laser Bar Optical Trapping in Microfluidics  

Science Journals Connector (OSTI)

We present a simple, compact, microfluidic system that easily facilitates diode laser bar optical trapping for cell stretching measurements and particle sorting within flowing...

Applegate Jr , Robert W; Squier, Jeff; Vestad, Tor; Oakey, John; Marr, David W

398

Nano-particle trapping by optically induced Dielectrophoresis enhanced by nano-antennas  

Science Journals Connector (OSTI)

We demonstrate experimentally trapping and manipulation of 50nm gold nanoparticles suspended in Isopropanol using dielectrophoretic (DEP) forces induced by illuminating arrays of...

Yifat, Yuval; Eitan, Michal; Scheuer, Jacob

399

E-Print Network 3.0 - aerosol trapping effect Sample Search Results  

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

of this infrared radiation is trapped... 'S TEMPERATURE IS RISING This is the greenhouse effect. Without it, the Earths climate would be ... Source: Brookhaven National...

400

Comparison of methods to quantify interface trap densities at dielectric/IIIV semiconductor interfaces  

E-Print Network (OSTI)

and a series resistance R s . ?c? Equivalent circuit of theresistance, R s . The in- terface trap density contributes an equivalent

Stemmer, Susanne

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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

QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARY LATTICE PROPOSAL .  

E-Print Network (OSTI)

??A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent… (more)

Korenblit, Simcha

2013-01-01T23:59:59.000Z

402

Characterization of particle- and vapor-phase organic fraction emissions from a heavy-duty diesel engine equipped with a particle trap and regeneration controls  

SciTech Connect

The effects of a ceramic particle trap on the chemical and biological character of the exhaust from a heavy-duty diesel engine have been studied during steady-state operation and during periods of trap regeneration. Phase I of this project involved developing and refining the methods using a Caterpillar 3208 engine, and Phase II involved more detailed experiments with a Cummins LTA10-300 engine, which met Federal 1988 particulate matter standards, and a ceramic particle trap with built-in regeneration controls. During the Phase I experiments, samples wee collected at the Environmental Protection Agency (EPA)* steady-state mode 4 (50% load at intermediate speed). Varying the dilution ratio to obtain a constant filter-face temperature resulted in less variability in total particulate matter (TPM), particle-associated soluble organic fraction (SOF), solids (SOL), and polynuclear aromatic hydrocarbon (PAH) levels than sampling with a constant dilution ratio and allowing filter-face temperature to vary. A modified microsuspension Ames assay detected mutagenicity in the SOF samples, and in the semivolatile organic fraction extracted from XAD-2 resin (XAD-2 resin organic component, XOC) with at least 10 times less sample mass than the standard plate incorporation assay. Measurement techniques for PAH and nitro-PAH in the SOF and XOC also were developed during this portion of the project. For the Phase II work, two EPA steady-state rated speed modes were selected: mode 11 (25% load) and mode 9 (75% load). With or without the trap, filter-face temperatures were kept at 45 degrees +/- 2 degrees C, nitrogen dioxide (NO2) levels less than 5 parts per million (ppm), and sampling times less than 60 minutes. Particle sizes were determined using an electrical aerosol analyzer. Similar sampling methods were used when the trap was regenerated, except that a separate dilution tunnel and sampling system was designed and built to collect all of the regeneration emissions.

Bagley, S.T.; Gratz, L.D.; Leddy, D.G.; Johnson, J.H. (Michigan Technological Univ., Houghton, MI (United States))

1993-07-01T23:59:59.000Z

403

Water Trapping on Tidally Locked Terrestrial Planets Requires Special Conditions  

E-Print Network (OSTI)

Surface liquid water is essential for standard planetary habitability. Calculations of atmospheric circulation on tidally locked planets around M stars suggest that this peculiar orbital configuration lends itself to the trapping of large amounts of water in kilometers-thick ice on the night side, potentially removing all liquid water from the day side where photosynthesis is possible. We study this problem using a global climate model including coupled atmosphere, ocean, land, and sea-ice components as well as a continental ice sheet model driven by the climate model output. For a waterworld we find that surface winds transport sea ice toward the day side and the ocean carries heat toward the night side. As a result, night-side sea ice remains O(10 m) thick and night-side water trapping is insignificant. If a planet has large continents on its night side, they can grow ice sheets O(1000 m) thick if the geothermal heat flux is similar to Earth's or smaller. Planets with a water complement similar to Earth's w...

Yang, Jun; Hu, Yongyun; Abbot, Dorian S

2014-01-01T23:59:59.000Z

404

Dudley Ridge, a geomorphic trap - lacustrine gas in California  

SciTech Connect

The Dudley Ridge gas field is about 6 mi southeast of Kettleman City, California. The abandoned field straddles the boundary between T23S, R19E, and T23S, R20E, MDBM, in Kings County, California. The Tulare Lake depression was formed during the Pleistocene. It is bounded by the Temblor Range on the west, the Sierra Nevada rise on the east, the north tilt of the San Joaquin Valley to the south, and a gentle rise in the San Joaquin Valley floor to the north. The depression is almost circular except for the west side where North Kettleman dome formed a peninsula. The prevailing longshore current was to the south due to Coriolis-directed winds. Dudley Ridge was formed as a spit, trailing south off the side of North Kettleman dome. The spit is sandy, silty clay, with sand lense onlaps. The geomorphic trap formed by the sand lenses serves as a trap for the methane gas being produced in the organic-rich lake-bed sediments.

Sugden, H.E.

1986-04-01T23:59:59.000Z

405

Effect of atomic scale plasticity on hydrogen diffusion in iron: Quantum mechanically informed and on-the-fly kinetic  

E-Print Network (OSTI)

viewpoints, is futile. Among several mechanisms proposed for hydrogen embrittlement (HE) of metals, hydrogenEffect of atomic scale plasticity on hydrogen diffusion in iron: Quantum mechanically informed-assisted diffusion and trapping of hydrogen by crystalline defects in iron. Given an embedded atom (EAM) potential

Ortiz, Michael

406

Intrinsic Time Quantum Geometrodynamics  

E-Print Network (OSTI)

Quantum Geometrodynamics with intrinsic time development and momentric variables is presented. An underlying SU(3) group structure at each spatial point regulates the theory. The intrinsic time behavior of the theory is analyzed, together with its ground state and primordial quantum fluctuations. Cotton-York potential dominates at early times when the universe was small; the ground state naturally resolves Penrose's Weyl Curvature Hypothesis, and thermodynamic and gravitational `arrows of time' point in the same direction. Ricci scalar potential corresponding to Einstein's General Relativity emerges as a zero-point energy contribution. A new set of fundamental canonical commutation relations without Planck's constant emerges from the unification of Gravitation and Quantum Mechanics.

Eyo Eyo Ita III; Chopin Soo; Hoi-Lai Yu

2015-01-26T23:59:59.000Z

407

Relativistic viscoelastic fluid mechanics  

SciTech Connect

A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

Fukuma, Masafumi; Sakatani, Yuho [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

2011-08-15T23:59:59.000Z

408

Ion Crystals Produced by Laser and Sympathetic Cooling in a Linear RF Ion Trap  

E-Print Network (OSTI)

A detailed investigation of ion crystals produced by laser and sympathetic cooling in a linear RF trap has been conducted. The laser cooling methods were examined and applied to the trapped ^24Mg^(positive) ions. The crystals produced by the laser...

Zhu, Feng

2012-02-14T23:59:59.000Z

409

Laser Stabilization for Quantum Computing with Trapped Barium ions Corey Adams  

E-Print Network (OSTI)

Laser Stabilization for Quantum Computing with Trapped Barium ions Corey Adams University of Rochester (Dated: November 11, 2009) ABSTRACT The goal of this project was to stabilize a laser cooling system used to trap and cool Ba+ ions used for quantum computation research. The lasers, at 650 and 985

Blinov, Boris

410

ccsd00000593 Collective modes of a trapped Lieb-Liniger gas  

E-Print Network (OSTI)

ccsd­00000593 (version 1) : 11 Sep 2003 Collective modes of a trapped Lieb-Liniger gas September 11, 2003) We consider a trapped repulsive one-dimensional (1D) Bose gas at very low temperature, where the gas is locally described by the Lieb-Liniger model of bosons interacting via a repulsive delta

411

Surface-Enhanced Raman Scattering with Ag Nanoparticles Optically Trapped by a Photonic Crystal Cavity  

E-Print Network (OSTI)

on the chemical to be sensed. Figure 1a shows a schematic diagram of the trapping-assisted SERS platform we) platform by optically trapping Ag nanoparticles with a photonic crystal cavity integrated, unattended systems for the continual monitoring of chemicals in air and water. A high- performance substrate

412

Trapped-particle diocotron modes T. J. Hilsabeck and T. M. O'Neil  

E-Print Network (OSTI)

Trapped-particle diocotron modes T. J. Hilsabeck and T. M. O'Neil Department of Physics, University rate, and eigenmode structure are compared to experimental observation. The modes are excited on a non-neutral plasma column in which classes of trapped and passing particles have been created by the application

California at San Diego, University of

413

MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE-SCALE ISOELECTRIC TRAPPING SEPARATIONS  

E-Print Network (OSTI)

MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE- SCALE ISOELECTRIC TRAPPING SEPARATIONS A Dissertation by ROBERT YATES NORTH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2009 Major Subject: Chemistry MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE- SCALE ISOELECTRIC TRAPPING SEPARATIONS A Dissertation by ROBERT YATES NORTH...

North, Robert Yates

2011-08-08T23:59:59.000Z

414

NEUTRON LIFETIME EXPERIMENT USING UCN STORAGE IN AN `ACCORDION-LIKE' TRAP  

E-Print Network (OSTI)

NEUTRON LIFETIME EXPERIMENT USING UCN STORAGE IN AN `ACCORDION-LIKE' TRAP BY ASHISH M. DESAI determination of the neutron lifetime has an impact on particle physics and cosmology. We report progress towards a measurement of the neutron lifetime using an accordion-like storage trap. Ultracold neutrons

Steyerl, Albert

415

M4C3 precipitation in FeCMoV steels and relationship to hydrogen trapping  

E-Print Network (OSTI)

, Pembroke Street, Cambridge CB2 3QZ, UK Strong steels suffer from embrittlement due to dissolved hydrogenM4C3 precipitation in Fe­C­Mo­V steels and relationship to hydrogen trapping BY S. YAMASAKI AND H, a phenomenon which can be mitigated by trapping the hydrogen at carbide particles, where it is rendered benign

Cambridge, University of

416

Video Article A Microfluidic-based Hydrodynamic Trap for Single Particles  

E-Print Network (OSTI)

Video Article A Microfluidic-based Hydrodynamic Trap for Single Particles Eric M. Johnson). A Microfluidic-based Hydrodynamic Trap for Single Particles. JoVE. 47. http://www.jove.com/details.php?id=2517 and biology ranging from the molecular to cellular level. In this article, we introduce a new microfluidic

Schroeder, Charles

417

Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1  

E-Print Network (OSTI)

Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1 S. Younis,1 atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimen- tally sustainable nanotube currents, generating

Joselevich, Ernesto

418

Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms  

E-Print Network (OSTI)

1 Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms Jerzy of the lasers used in the set-up. 1. Introduction Atomic physics has noticed recently a rapid development of research on different methods of cooling and trapping of atoms with use of optical forces (light pressure

419

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light  

E-Print Network (OSTI)

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose "walls" are magnetic fields. Cooled atoms are ideal for exploring basic. research has traditionally been the study of the intrinsic prop erties of isolated atoms. In the early part

Johannesson, Henrik

420

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell  

E-Print Network (OSTI)

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell 24 SEPTEMBER sample of spin-polarized trapped atoms. The technique used dramati- cally simplifies the production of laser-cooled atoms. In this experiment, 1.8x10' neutral cesium atoms were optically captured directly

Monroe, Christopher

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Cooling and Heating of the Quantum Motion of Trapped Cd+ Louis Deslauriers  

E-Print Network (OSTI)

of fluctuating electric fields with the motional state of the ion leads to heating and thus to decoherence of decoherence in ion traps and possibly other charge-based quantum systems. #12;Cooling and HeatingABSTRACT Cooling and Heating of the Quantum Motion of Trapped Cd+ Ions by Louis Deslauriers Chair

Monroe, Christopher

422

Trapping of ultracold atoms in a hollow-core photonic crystal fiber Caleb A. Christensen,1  

E-Print Network (OSTI)

light in multiple modes in the cladding or core. Such fibers are susceptible to speckle or inhomogeneous have succeeded in trapping ultracold atoms 13 or guiding thermal 14 or laser-cooled atoms 15 through laser cooling and rf evaporation in a dc Ioffe-Pritchard magnetic trap, then load the BEC into a red

423

The trapped-particle instability in the Boeing 1kW FEL oscillator  

SciTech Connect

The new design for the Boeing High Average Power Free Electron Laser will operate at 1KW average power (0.63 {mu}m) with a peak current of 132A. Simulations are used to investigate the trapped-particle instability and diffraction effects. Incorporating large desynchronism may prove to be a useful method of controlling the trapped-particle instability.

Ramos, L.; Blau, J.; Colson, W.B. [Naval Postgraduate School, Monterey, CA (United States)

1995-12-31T23:59:59.000Z

424

Oscillating Magnetic Trap and Non-Thermal Emission from Solar Flares  

Science Journals Connector (OSTI)

......connected with the electron thermal conductivity and ion viscosity...1, ed. Galeev A. A., Sudan R. N. (North-Holland Physics...Oscillating Magnetic Trap and Non-Thermal Emission from Solar Flares...scattering of trapped non-thermal electrons (Aschwanden et al......

Yuri Tsap; Yulia Kopylova; Tatiana Goldvarg; Alexander Stepanov

2013-12-05T23:59:59.000Z

425

Ground state cooling, quantum state engineering and study of decoherence of ions in Paul traps  

E-Print Network (OSTI)

Ground state cooling, quantum state engineering and study of decoherence of ions in Paul traps F March 2000; revision received 23 June 2000) Abstract. We investigate single ions of 40 Ca in Paul traps for the manipulation of the ion' s quantum state. We apply sideband cooling to the ion and reach the ground state

Blatt, Rainer

426

Fundamental limit of light trapping in grating Zongfu Yu, Aaswath Raman and Shanhui Fan+  

E-Print Network (OSTI)

­305 (1982). 5. M. A. Green, "Lambertian light trapping in textured solar cells and light-emitting diodes. I. Tobías, A. Luque, and A. Marti, "Light intensity enhancement by diffracting structures in solar of nanophotonic light trapping for solar cells," arXiv:1004.2902v2 [physics.optics] (2010). http

Fan, Shanhui

427

Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Kelsey A. Whitesell*a  

E-Print Network (OSTI)

Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Crystals Kelsey A. Whitesell to enhance performance of thin film solar cells because of their unique ability to control light. We show for light trapping in thin film photovoltaics. Keywords: photonic crystals, defect, silicon, solar cell

Atwater, Harry

428

Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Cells  

E-Print Network (OSTI)

Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Sciences Division, Lawrence Berkeley National Laboratory July 23, 2013 Abstract Light trapping in solar the surface of the solar cell, where n is the material refractive index. This ray-optics absorption

California at Irvine, University of

429

Light trapping design for low band-gap polymer solar cells  

E-Print Network (OSTI)

Light trapping design for low band-gap polymer solar cells Stephen Foster1,* and Sajeev John1,2 1 demonstrate numerically a 2-D nanostructured design for light trapping in a low band-gap polymer solar cell, "Light harvesting improvement of organic solar cells with self- enhanced active layer designs," Opt

John, Sajeev

430

3D modeling of magnetic atom traps on type-II superconductor chips  

E-Print Network (OSTI)

Israel 2 A. Yersin Department of Solar Energy and Environmental Physics, The Blaustein Institutes. The proposed approach allows us to predict important characteristics of the magnetic traps (their depth, shape, and in the usage of trapped atoms to probe local irregularities of magnetic and electric fields near conductive

Prigozhin, Leonid

431

Optical diagnostics of cold (I'mK atoms in the magneto-optical trap  

E-Print Network (OSTI)

Optical diagnostics of cold (I'mK atoms in the magneto-optical trap Tomasz M. Brzozowski, Witold with the spectroscopic methods. In this paper, we present basic principles ofobtaining ultra-cold atoms and methods used-OFHCAL TRAP Temperatures of atoms in gaseous phase below 1 mK are nowadays routinely reached with the help

432

NREL experiments show that disordered inverse opals significantly scatter and trap near-infrared light, with  

E-Print Network (OSTI)

NREL experiments show that disordered inverse opals significantly scatter and trap near-infrared wavelengths in the near-infrared (NIR), which is important to a number of technologies. This discovery.neale@nrel.gov Reference: N.R. Neale, B.G. Lee, S.H. Kang, and A.J. Frank."Near-Infrared Light Trapping in Disordered

433

Title of dissertation: QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS  

E-Print Network (OSTI)

are intractable. #12;QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARYABSTRACT Title of dissertation: QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARY LATTICE PROPOSAL Simcha Korenblit, Doctor of Philosophy 2013 Dissertation directed

Monroe, Christopher

434

Light traps are one of a number of different gears used to sample  

E-Print Network (OSTI)

phases, current speed or water Effects of current speed and turbidity on stationary light-trap catches measurements of cur- rent speed and turbidity. Materials and methods Study sites Larval and juvenile fishes438 Light traps are one of a number of different gears used to sample pelagic larval and juvenile

435

Steven Chu: Laser Cooling and Trapping of Atoms  

Office of Scientific and Technical Information (OSTI)

Steven Chu Steven Chu Laser Cooling and Trapping of Atoms Resources with Additional Information · Interviews, Speeches, and Presentations · Patents Steven Chu Photo Credit: Lawrence Berkeley National Laboratory Roy Kaltschmidt, Photographer Steven Chu was appointed by President Barack Obama to be the 12th Secretary of Energy and served in this capacity until April 22, 2013. He was previously Director of Lawrence Berkeley National Laboratory (LBNL), Professor in the Physics Department at the University of California, Berkeley, and 'the Theodore and Frances Geballe Professor of Physics and Applied Physics at Stanford University. Professor Chu's research is in atomic physics, polymer and biophysics. His thesis and postdoctoral work at Berkeley ... was the observation of parity non-conservation in atomic transitions in 1978. This experiment was one of the earliest atomic physics confirmations of the Weinberg-Salam-Glashow theory that unifies the weak and electromagnetic forces.

436

Steven Chu: Laser Cooling and Trapping of Atoms  

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

Steven Chu Steven Chu Laser Cooling and Trapping of Atoms Resources with Additional Information · Interviews, Speeches, and Presentations · Patents Steven Chu Photo Credit: Lawrence Berkeley National Laboratory Roy Kaltschmidt, Photographer Steven Chu was appointed by President Barack Obama to be the 12th Secretary of Energy and served in this capacity until April 22, 2013. He was previously Director of Lawrence Berkeley National Laboratory (LBNL), Professor in the Physics Department at the University of California, Berkeley, and 'the Theodore and Frances Geballe Professor of Physics and Applied Physics at Stanford University. Professor Chu's research is in atomic physics, polymer and biophysics. His thesis and postdoctoral work at Berkeley ... was the observation of parity non-conservation in atomic transitions in 1978. This experiment was one of the earliest atomic physics confirmations of the Weinberg-Salam-Glashow theory that unifies the weak and electromagnetic forces.

437

Laser cooling of a trapped particle with increased Rabi frequencies  

E-Print Network (OSTI)

This paper analyses the cooling of a single particle in a harmonic trap with red-detuned laser light with fewer approximations than previously done in the literature. We avoid the adiabatic elimination of the excited atomic state but are still interested in Lamb-Dicke parameters $\\eta \\ll 1$. Our results show that the Rabi frequency of the cooling laser can be chosen higher than previously assumed, thereby increasing the effective cooling rate but {\\em not} affecting the final outcome of the cooling process. Since laser cooling is already a well established experimental technique, the main aim of this paper is to present a model which can be extended to more complex scenarios, like cavity-mediated laser cooling.

Tony Blake; Andreas Kurcz; Norah S. Saleem; Almut Beige

2011-10-14T23:59:59.000Z

438

Hydrogen trapping in ?-Pu: insights from electronic structure calculations  

Science Journals Connector (OSTI)

Density functional theory calculations have been performed to provide details of the structural and charge-transfer details related to the solid solution of hydrogen in (?)-plutonium. We follow the Flanagan model that outlines the process by which hydrogen interacts with a metal to produce hydride phases, via a sequence of surface, interstitial and defect-bound (trapped) states. Due to the complexities of the electronic structure in plutonium solid-state systems, we take the pragmatic approach of adopting the 'special quasirandom structure' to disperse the atomic magnetic moments. We find that this approach produces sound structural and thermodynamic properties in agreement with the available experimental data. In ?-Pu, hydrogen has an exothermic binding energy to all of the states relevant in the Flanagan model, and, furthermore, is anionic in all these states. The charge transfer is maximized (i.e. most negative for hydrogen) in the hydride phase. The pathway from surface to hydride is sequentially exothermic, in the order surface

Christopher D Taylor; Sarah C Hernandez; Michael F Francis; Daniel S Schwartz; Asok K Ray

2013-01-01T23:59:59.000Z

439

Theory of indirect exciton photoluminescence in elevated quantum trap  

Science Journals Connector (OSTI)

Abstract Inspired by an experiment of indirect excitons photoluminescence (PL) in elevated quantum trap (High et al., 2009), we theoretically investigate the energy relaxation and nonlinear interactions of indirect excitons in coupled quantum wells. It is shown that, when increasing the laser power, the intensity reversion of two PL peaks is due to the phonon necklace effect. In addition, we use a nonlinear Schrödinger equation including attractive two-body, repulsive three-body interactions and the excitation power dependence of energy distribution to understand the exciton states. This model gives a natural account for the PL blue shift with the increase of the excitation power. This study thus provides an alternative way to understand the underlying physics of the exciton dynamics in coupled potential wells.

C.S. Liu; T.F. Xu; Y.H. Liu; X.L. Jing

2014-01-01T23:59:59.000Z

440

Lean Gasoline Engine Reductant Chemistry During Lean NOx Trap Regeneration  

SciTech Connect

Lean NOx Trap (LNT) catalysts can effectively reduce NOx from lean engine exhaust. Significant research for LNTs in diesel engine applications has been performed and has led to commercialization of the technology. For lean gasoline engine applications, advanced direct injection engines have led to a renewed interest in the potential for lean gasoline vehicles and, thereby, a renewed demand for lean NOx control. To understand the gasoline-based reductant chemistry during regeneration, a BMW lean gasoline vehicle has been studied on a chassis dynamometer. Exhaust samples were collected and analyzed for key reductant species such as H2, CO, NH3, and hydrocarbons during transient drive cycles. The relation of the reductant species to LNT performance will be discussed. Furthermore, the challenges of NOx storage in the lean gasoline application are reviewed.

Choi, Jae-Soon [ORNL] [ORNL; Prikhodko, Vitaly Y [ORNL] [ORNL; Partridge Jr, William P [ORNL] [ORNL; Parks, II, James E [ORNL; Norman, Kevin M [ORNL] [ORNL; Huff, Shean P [ORNL] [ORNL; Chambon, Paul H [ORNL] [ORNL; Thomas, John F [ORNL] [ORNL

2010-01-01T23:59:59.000Z

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


441

A novel approach for enhanced visible light activity in doped nanosize titanium dioxide through the excitons trapping  

SciTech Connect

Titanium dioxide doped with iron oxide (0-10 mol%) has been synthesized by an aqueous sol-gel method. The extent of phase transformation is higher in presence of up to 1 mol% of Fe{sup 3+} ions in doped titania. A further increase in Fe{sup 3+} content was found to decrease the phase transformation. A composition which contains {approx}90% rutile and the remaining anatase phase shows the highest photocatalytic activity. Even though surface area values are dramatically decreased by the modification of TiO{sub 2} by Fe{sup 3+} doping, crystallinity plays a major role in photocatalytic activity enhancement. UV-vis reflectance spectra indicate a red-shift in band gap energy and thus an enhanced photoactivity in visible light, suitable for application in photodegradation of toxic industrial effluents as well as other organic contaminants, is achieved. Low concentrations of Fe{sup 3+} ions act as excitons trapping centers, while higher concentrations act as recombination centers. The synergy between the rutile-anatase ratios and optimum amount of Fe{sup 3+} ions improve the interfacial charge transfer and trapping which enhanced the photochemical degradation of MB dye. The Fe{sup 3+} doped TiO{sub 2} composition has the highest photoactivity, having an apparent rate constant of 11.1 Multiplication-Sign 10{sup -3} min{sup -1}, which is much higher than that of commercial P25 Degussa titania (6.03 Multiplication-Sign 10{sup -3} min{sup -1}). - Graphical abstract: Model explaining the transfer and trapping of e{sup -}/h{sup +} pairs in mixed phase titania by Fe{sup 3+} ions suggests the reason for the increased lifetime of e{sup -}/h{sup +} pairs and enhanced photocatalytic activity. Highlights: Black-Right-Pointing-Pointer An aqueous sol-gel method for the preparation of doped TiO{sub 2} is being reported. Black-Right-Pointing-Pointer High photocatalytic activity and simplicity are the novelty of this work. Black-Right-Pointing-Pointer Enhanced activity is explained by the mechanism of trapping of charges.

Jaimy, Kanakkanmavudi B.; Baiju, K.V.; Ghosh, Swapankumar [National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695019 (India); Warrier, K.G.K., E-mail: wwarrierkgk@yahoo.co.in [National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695019 (India)

2012-02-15T23:59:59.000Z

442

Penning traps with unitary architecture for storage of highly charged ions  

E-Print Network (OSTI)

Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two- magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed.

Tan, Joseph N; Guise, Nicholas D; 10.1063/1.3685246

2012-01-01T23:59:59.000Z

443

Adiabatic electron response and solitary wave generation by trapped particle nonlinearity in a hydrogen plasma  

SciTech Connect

The finite amplitude ion acoustic waves that trap electrons modify the structure of the evolving nonlinear soliton solutions. In the numerical simulations, self-consistently generated solitary waves are studied that emerge as a result of a current driven microinstability growing the ion acoustic mode in a collisionless Vlasov plasma. The growth saturates as a result of nonlinear effects governed by a combination of nonlinearities originating from the hydrodynamic model and kinetic particle trapping effects. The resulting solitary waves also coexist with a finite current and an electron plasma wave capable of perturbing the trapping potential. The results of multiscale simulation are analyzed and characterized following the kinetic prescription of undamped trapped particle mode in the form of phase space vortex solutions that are generalized form of Sagdeev's solitons and obey the solutions of a modified Korteweg-de Vries equation, accounting for a stronger nonlinearity originating from the electron trapping.

Mandal, Debraj; Sharma, Devendra [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2014-10-15T23:59:59.000Z

444

Accuracy estimations of overtone vibrational transition frequencies of optically trapped 174Yb6Li molecules  

Science Journals Connector (OSTI)

The attainable accuracy of the X2?(v,N)=(0,0)?(vu,0) transition frequencies of optically trapped 174Yb6Li molecules are analyzed (vu=1,2,3,4) to test the variation in the proton-to-electron mass ratio. We eliminate the Stark shifts induced by the trap and Raman lasers by choosing appropriate frequencies (magic frequencies). For vu=1 and 2, we obtain more than one experimentally useful magic frequency, thereby leading to more choice in the trap laser. For vu=3 and 4, the choice in the trap laser is limited. The systematic frequency uncertainty is given by the trap laser frequency detuning from the magic frequency and the fluctuation of the power ratio of the two Raman lasers and can be lower than 10?16 for all these transition frequencies. To obtain lower statistical uncertainty, measurement with vu=4 is more advantageous than that with vu=1?3.

Masatoshi Kajita; Geetha Gopakumar; Minori Abe; Masahiko Hada

2012-06-28T23:59:59.000Z

445

Selective Trapping of Volatile Fission Products with an Off-Gas Treatment System  

SciTech Connect

A head-end processing step, termed DEOX for its emphasis on decladding via oxidation, is being developed for the treatment of spent oxide fuel by pyroprocessing techniques. The head-end step employs high temperatures to oxidize UO2 to U3O8 resulting in the separation of fuel from cladding and the removal of volatile fission products. Development of the head-end step is being performed in collaboration with the Korean Atomic Energy Research Institute (KAERI) through an International Nuclear Energy Research Initiative. Following the initial experimentation for the removal of volatile fission products, an off-gas treatment system was designed in conjunction with KAERI to collect specific fission gases. The primary volatile species targeted for trapping were iodine, technetium, and cesium. Each species is intended to be collected in distinct zones of the off-gas system and within those zones, on individual filters. Separation of the volatile off-gases is achieved thermally as well as chemically given the composition of the filter media. A description of the filter media and a basis for its selection will be given along with the collection mechanisms and design considerations. In addition, results from testing with the off-gas treatment system will be presented.

B.R. Westphal; J.J. Park; J.M. Shin; G.I. Park; K.J. Bateman; D.L. Wahlquist

2008-07-01T23:59:59.000Z

446

PhD position in trapped ion quantum technology and nanoscience at the University of Sussex, Brighton, UK  

E-Print Network (OSTI)

PhD position in trapped ion quantum technology and nanoscience at the University of Sussex a quantum computer with trapped ions. Research in the group focuses on the borderland of nanoscience

Hensinger, Winfried

447

Mechanical & Aerospace Engineering  

E-Print Network (OSTI)

Mechanical & Aerospace Engineering An experimental methodology is presented for mechanism verification of physics-based prognosis of mechanical damage, such as fatigue. The proposed experimental methodology includes multi-resolution in-situ mechanical testing, advanced imaging analysis, and mechanism

448

On the foundation of Mechanics  

E-Print Network (OSTI)

This note is an extended version of "A note on the foundations of Mechanics", arXiv: 1404.1321 [math-ph]. A presentation of its contents was given in a talk in memorial homage to the professor Juan B. Sancho Guimer\\'a. For this reason, it was written in spanish language. The matter of the note is a systematic foundation of the most classical part of Mechanics. The content by sections is: 0) Notions and basic results, 1) Conservative systems 2) Time. Time constraints, 3) Proper time. Relativistic forces, 4) Electromagnetic fields, 5) On the Hamilton-Noether Principle, 6) Schr\\"odinger equation.

Ricardo J. Alonso-Blanco; Jesús Muñoz-Díaz

2014-12-09T23:59:59.000Z

449

Comparison of Ag and SiO2 Nanoparticles for Light Trapping Applications in Silicon Thin Film Solar Cells  

Science Journals Connector (OSTI)

Comparison of Ag and SiO2 Nanoparticles for Light Trapping Applications in Silicon Thin Film Solar Cells ... † Department

Martin Theuring; Peng Hui Wang; Martin Vehse; Volker Steenhoff; Karsten von Maydell; Carsten Agert; Alexandre G. Brolo

2014-09-10T23:59:59.000Z

450

Black Silicon Solar Thin-film Microcells Integrating Top Nanocone Structures for Broadband and Omnidirectional Light-Trapping  

E-Print Network (OSTI)

Recently developed classes of monocrystalline silicon solar microcells (u-cell) can be assembled into modules with characteristics (i.e., mechanically flexible forms, compact concentrator designs, and high-voltage outputs) that would be impossible to achieve using conventional, wafer-based approaches. In this paper, we describe a highly dense, uniform and non-periodic nanocone forest structure of black silicon (bSi) created on optically-thin (30 um) u-cells for broadband and omnidirectional light-trapping with a lithography-free and high-throughput plasma texturizing process. With optimized plasma etching conditions and a silicon nitride passivation layer, black silicon u-cells, when embedded in a polymer waveguiding layer, display dramatic increases of as much as 65.7% in short circuit current, as compared to a bare silicon device. The conversion efficiency increases from 8% to 11.5% with a small drop in open circuit voltage and fill factor.

Xu, Zhida; Brueckner, Eric P; Li, Lanfang; Jiang, Jing; Nuzzo, Ralph G; Liu, Gang L

2014-01-01T23:59:59.000Z

451

PEBBLES Mechanics Simulation Speedup  

SciTech Connect

Pebble bed reactors contain large numbers of spherical fuel elements arranged randomly. Determining the motion and location of these fuel elements is required for calculating certain parameters of pebble bed reactor operation. These simulations involve hundreds of thousands of pebbles and involve determining the entire core motion as pebbles are recirculated. Single processor algorithms for this are insufficient since they would take decades to centuries of wall-clock time. This paper describes the process of parallelizing and speeding up the PEBBLES pebble mechanics simulation code. Both shared memory programming with the Open Multi-Processing API and distributed memory programming with the Message Passing Interface API are used in simultaneously in this process. A new shared memory lock-less linear time collision detection algorithm is described. This method allows faster detection of pebbles in contact than generic methods. These combine to make full recirculations on AVR sized reactors possible in months of wall clock time.

Joshua J. Cogliati; Abderrafi M. Ougouag

2010-05-01T23:59:59.000Z

452

Insensitivity of the rate of ion motional heating to trap-electrode material over a large temperature range  

E-Print Network (OSTI)

We present measurements of trapped-ion motional-state heating rates in niobium and gold surface-electrode ion traps over a range of trap-electrode temperatures from approximately 4 K to room temperature (295 K) in a single ...

Chiaverini, John

453

Development and test of a cryogenic trap system dedicated to confinement of radioactive volatile isotopes in SPIRAL2 post-accelerator  

Science Journals Connector (OSTI)

A cryogenic trap system called Cryotrap has been studied and developed in the framework of nuclear safety studies for SPIRAL2 accelerator. The main objective of Cryotrap is to confine and reduce strongly the migration of radioactive volatile isotopes in beam lines. These radioactive gases are produced after interaction between a deuteron beam and a fissile target. Mainly, Cryotrap is composed by a vacuum vessel and two copper thermal screens maintained separately at two temperatures T1=80 K and T2=20 K. A Cryocooler with two stages at previous temperatures is used to remove static heat losses of the cryostat and ensure an efficient cooling of the system. Due to strong radiological constraints that surround Cryotrap, the coupling system between Cryocooler and thermal screens is based on aluminum thermo-mechanical contraction. The main objective of this original design is to limit direct human maintenance interventions and provide maximum automated operations. A preliminary prototype of Cryotrap has been developed and tested at GANIL laboratory to validate its design, and determine its thermal performance and trapping efficiency. In this paper, we will first introduce briefly SPIRAL2 project and discuss the main role of Cryotrap in nuclear safety of the accelerator. Then, we will describe the proposed conceptual design of Cryotrap and its main characteristics. After that, we will focus on test experiment and analyze experimental data. Finally, we will present preliminary results of gas trapping efficiency tests.

M. Souli; P. Dolégiéviez; M. Fadil; P. Gallardo; R. Levallois; H. Munoz; M. Ozille; G. Rouillé; F. Galet

2011-01-01T23:59:59.000Z

454

Self-interfering matter-wave patterns generated by a moving laser obstacle in a two-dimensional Bose-Einstein condensate inside a power trap cut off by box potential boundaries  

SciTech Connect

We report the observation of highly energetic self-interfering matter-wave (SIMW) patterns generated by a moving obstacle in a two-dimensional Bose-Einstein condensate (BEC) inside a power trap cut off by hard-wall box potential boundaries. The obstacle initially excites circular dispersive waves radiating away from the center of the trap which are reflected from hard-wall box boundaries at the edges of the trap. The resulting interference between outgoing waves from the center of the trap and reflected waves from the box boundaries institutes, to the best of our knowledge, unprecedented SIMW patterns. For this purpose we simulated the time-dependent Gross-Pitaevskii equation using the split-step Crank-Nicolson method and the obstacle was modelled by a moving impenetrable Gaussian potential barrier. Various trapping geometries are considered in which the dynamics of the spatial and momentum density, as well as the energy, are considered. The momentum dynamics reveal an oscillatory behavior for the condensate fraction, indicative of excitations out of and de-excitations back into the condensate state. An oscillatory pattern for the energy dynamics reveals the presence of solitons in the system. Some vortex features are also obtained.

Sakhel, Roger R. [Department of Basic Sciences, Faculty of Information Technology, Isra University, Amman 11622 (Jordan); Sakhel, Asaad R. [Department of Applied Sciences, Faculty of Engineering Technology, Al-Balqa Applied University, Amman 11134 (Jordan); Ghassib, Humam B. [Department of Physics, The University of Jordan, Amman 11942 (Jordan)

2011-09-15T23:59:59.000Z

455

Bose-Einstein condensation in dark power-law laser traps  

SciTech Connect

We investigate theoretically an original route to achieve Bose-Einstein condensation using dark power-law laser traps. We propose to create such traps with two crossing blue-detuned Laguerre-Gaussian optical beams. Controlling their azimuthal order l allows for the exploration of a multitude of power-law trapping situations in one, two, and three dimensions, ranging from the usual harmonic trap to an almost square-well potential, in which a quasihomogeneous Bose gas can be formed. The usual cigar-shaped and disk-shaped Bose-Einstein condensates obtained in a 1D or 2D harmonic trap take the generic form of a 'finger' or of a 'hockey puck' in such Laguerre-Gaussian traps. In addition, for a fixed atom number, higher transition temperatures are obtained in such configurations when compared with a harmonic trap of the same volume. This effect, which results in a substantial acceleration of the condensation dynamics, requires a better but still reasonable focusing of the Laguerre-Gaussian beams.

Jaouadi, A. [Universite Paris-Sud, Institut des Sciences Moleculaires d'Orsay (ISMO), F-91405 Orsay (France); CNRS, Orsay, F-91405 France (France); Laboratoire de Spectroscopie Atomique, Moleculaire et Applications (LSAMA), Department of Physics, Faculty of Science of Tunis, University of Tunis El Manar, T-2092 Tunis (Tunisia); Gaaloul, N. [Institut fuer Quantenoptik, Welfengarten 1, Gottfried Wilhelm Leibniz Universitaet, D-30167 Hannover (Germany); Viaris de Lesegno, B.; Pruvost, L. [CNRS, Laboratoire Aime Cotton (LAC), F-91405 Orsay (France); Universite Paris-Sud, Orsay, F-91405 France (France); Telmini, M. [Laboratoire de Spectroscopie Atomique, Moleculaire et Applications (LSAMA), Department of Physics, Faculty of Science of Tunis, University of Tunis El Manar, T-2092 Tunis (Tunisia); Charron, E. [Universite Paris-Sud, Institut des Sciences Moleculaires d'Orsay (ISMO), F-91405 Orsay (France); CNRS, Orsay, F-91405 (France)

2010-08-15T23:59:59.000Z

456

Confinement in a cryogenic penning trap of highest charge state ions from EBIT  

SciTech Connect

The retrapping of highly charged Xe[sup 44+] and Th[sup 68+,72+] ions extracted from an electron-beam ion trap'' (EBIT) is demonstrated after injection of the ions into RETRAP, a cryogenic Penning trap (up to 6 T magnetic field) currently with an open cylinder design. Ion extraction in a short pulse (5--20 [mu]s) from EBIT, essential for efficient retrapping, is employed. The ions are slowed down upon entering a deceleration tube mounted above the trap within the magnetic field. The potential is then rapidly (100 ns) decreased, enabling low-energy ions to enter the trap. Capture efficiencies up to 25% are observed via detection of the delayed ion release pulse with a detector below the trap. Signal voltages induced in a tuned circuit due to single and multiple ions have been observed by tuning the ion resonant axial oscillation frequencies for different ions. Results from transporting and retrapping of the ions, as well as their detection, are described and the trapping efficiency is discussed. The motivation for these studies is to cool the trapped very highly charged ions to low temperatures ([lt]4 K) in order to perform ultrahigh-resolution precision spectroscopy, collision studies at ultralow energies, and to observe phase transitions in Coulomb clusters of highly charged ions.

Schneider, D.; Church, D.A.; Weinberg, G.; Steiger, J.; Beck, B.; McDonald, J.; Magee, E.; Knapp, D. (Lawrence Livermore National Laboratory, Livermore, California 94550 (United States))

1994-11-01T23:59:59.000Z

457

Calculation of geometric phases in electric dipole searches with trapped spin-1/2 particles based on direct solution of the Schrödinger equation  

Science Journals Connector (OSTI)

Pendlebury etal. [Phys. Rev. A 70, 032102 (2004)] were the first to investigate the role of geometric phases in searches for an electric dipole moment (EDM) of elementary particles based on Ramsey-separated oscillatory field magnetic resonance with trapped ultracold neutrons and comagnetometer atoms. Their work was based on the Bloch equation and later work using the density matrix corroborated the results and extended the scope to describe the dynamics of spins in general fields and in bounded geometries. We solve the Schrödinger equation directly for cylindrical trap geometry and obtain a full description of EDM-relevant spin behavior in general fields, including the short-time transients and vertical spin oscillation in the entire range of particle velocities. We apply this method to general macroscopic fields and to the field of a microscopic magnetic dipole.

A. Steyerl; C. Kaufman; G. Müller; S. S. Malik; A. M. Desai; R. Golub

2014-05-22T23:59:59.000Z

458

Calculation of geometric phases in electric dipole searches with trapped spin-1/2 particles based on direct solution of the Schrödinger equation  

E-Print Network (OSTI)

Pendlebury $\\textit{et al.}$ [Phys. Rev. A $\\textbf{70}$, 032102 (2004)] were the first to investigate the role of geometric phases in searches for an electric dipole moment (EDM) of elementary particles based on Ramsey-separated oscillatory field magnetic resonance with trapped ultracold neutrons and comagnetometer atoms. Their work was based on the Bloch equation and later work using the density matrix corroborated the results and extended the scope to describe the dynamics of spins in general fields and in bounded geometries. We solve the Schr\\"odinger equation directly for cylindrical trap geometry and obtain a full description of EDM-relevant spin behavior in general fields, including the short-time transients and vertical spin oscillation in the entire range of particle velocities. We apply this method to general macroscopic fields and to the field of a microscopic magnetic dipole.

A. Steyerl; C. Kaufman; G. Müller; S. S. Malik; A. M. Desai; R. Golub

2014-05-23T23:59:59.000Z

459

Subtask 4.27 - Evaluation of the Multielement Sorbent Trap (MEST) Method at an Illinois Coal-Fired Plant  

SciTech Connect

Owners of fossil fuel-fired power plants face the challenge of measuring stack emissions of trace metals and acid gases at much lower levels than in the past as a result of increasingly stringent regulations. In the United States, the current reference methods for trace metals and halogens are wet-chemistry methods, U.S. Environmental Protection Agency (EPA) Methods 29 and 26 or 26A, respectively. As a possible alternative to the EPA methods, the Energy & Environmental Research Center (EERC) has developed a novel multielement sorbent trap (MEST) method to be used to sample for trace elements and/or halogens. Sorbent traps offer a potentially advantageous alternative to the existing sampling methods, as they are simpler to use and do not require expensive, breakable glassware or handling and shipping of hazardous reagents. Field tests comparing two sorbent trap applications (MEST-H for hydrochloric acid and MEST-M for trace metals) with the reference methods were conducted at two power plant units fueled by Illinois Basin bituminous coal. For hydrochloric acid, MEST measured concentrations comparable to EPA Method 26A at two power plant units, one with and one without a wet flue gas desulfurization scrubber. MEST-H provided lower detection limits for hydrochloric acid than the reference method. Results from a dry stack unit had better comparability between methods than results from a wet stack unit. This result was attributed to the very low emissions in the latter unit, as well as the difficulty of sampling in a saturated flue gas. Based on these results, the MEST-H sorbent traps appear to be a good candidate to serve as an alternative to Method 26A (or 26). For metals, the MEST trap gave lower detection limits compared to EPA Method 29 and produced comparable data for antimony, arsenic, beryllium, cobalt, manganese, selenium, and mercury for most test runs. However, the sorbent material produced elevated blanks for cadmium, nickel, lead, and chromium at levels that would interfere with accurate measurement at U.S. hazardous air pollutant emission limits for existing coal-fired power plant units. Longer sampling times employed during this test program did appear to improve comparative results for these metals. Although the sorbent contribution to the sample was reduced through improved trap design, additional research is still needed to explore lower-background materials before the MEST-M application can be considered as a potential alternative method for all of the trace metals. This subtask was funded through the EERC–U.S. Department of Energy Joint Program on Research and Development for Fossil Energy-Related Resources Cooperative Agreement No. DE-FC26-08NT43291. Nonfederal funding was provided by the Electric Power Research Institute, the Illinois Clean Coal Institute, Southern Illinois Power Company, and the Center for Air Toxic Metals Affiliates Program.

Pavlish, John; Thompson, Jeffrey; Dunham, Grant

2014-09-30T23:59:59.000Z

460

Canonical transformation for trapped/passing guiding-center orbits in axisymmetric tokamak geometry  

E-Print Network (OSTI)

The generating function for the canonical transformation from the parallel canonical coordinates $(p_{\\|},s)$ to the action-angle coordinates $(J,\\zeta)$ for trapped/passing guiding-center orbits in axisymmetric tokamak geometry is presented. Drawing on the analogy between the phase-space portraits of the librating/rotating pendulum and the trapped/passing guiding-center orbits, the generating function is expressed in terms of the Jacobi zeta function, which can then readily be used to obtain an explicit expression for the bounce-center transformation for trapped-particles in axisymmetric tokamak geometry.

Brizard, Alain J

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "timing trapping mechanism" 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
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461

Photoionization rates of Cs Rydberg atoms in a 1064-nm far-off-resonance trap  

SciTech Connect

Experimental measurements of photoionization rates of nD{sub 5/2} Rydberg states of Cs (50{<=}n{<=}75) in a 1064-nm far off-resonance dipole trap are presented. The photoionization rates are obtained by measuring the lifetimes of Rydberg atoms produced inside of a 1064-nm far off-resonance trap and comparing the lifetimes to corresponding control experiments in a magneto-optical trap. Experimental results for the control experiments agree with recent theoretical predictions for Rydberg state lifetimes and measured photoionization rates are in agreement with transition rates calculated from a model potential.

Tallant, J.; Booth, D.; Shaffer, J. P. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks Street, Norman, Oklahoma 73019 (United States)

2010-12-15T23:59:59.000Z

462

MoO3 trapping layers with CF4 plasma treatment in flash memory applications  

Science Journals Connector (OSTI)

Abstract In this research, we used MoO3 with CF4 plasma treatment as charge trapping layer in metal-oxide-high-k -oxide-Si-type memory. We analyzed material properties and electrical characteristics with multiple analyses. The plasma treatment could increase the trapping density, reduce the leakage current, expand band gap, and passivate the defect to enhance the memory performance. The MoO3 charge trapping layer memory with suitable CF4 plasma treatment is promising for future nonvolatile memory applications.

Chuyan Haur Kao; Hsiang Chen; Su-Zhien Chen; Chian Yu Chen; Kuang-Yu Lo; Chun Han Lin

2014-01-01T23:59:59.000Z

463

2-photon ionization and necessary laser and vacuum systems for experiments with trapped strontium ions  

E-Print Network (OSTI)

We describe a efficient way to photoionize strontium atoms in a linear radio-frequency trap. We use a 2-photon second order process to excite the autoionization resonance (4d2 + 5p2) 1D2. A doubled pulsed Ti:Saphire laser system is used at 431nm to provide 100fsec pulses at 82Mhz. The fabrication of the laser systems for addressing the Sr+ transitions necessary for laser cooling and excitation of quantum jumps, vacuum system and ion trap structure are also described in detail. With the current setup a easy and repeatable trapping of linear ion chains is achieved at UHV pressures.

E. Kirilov; S. Putterman

2007-12-03T23:59:59.000Z

464

Light Trapping for Thin Silicon Solar Cells by Femtosecond Laser Texturing: Preprint  

SciTech Connect

Femtosecond laser texturing is used to create nano- to micron-scale surface roughness that strongly enhances light-trapping in thin crystalline silicon solar cells. Light trapping is crucial for thin solar cells where a single light-pass through the absorber is insufficient to capture the weakly absorbed red and near-infrared photons, especially with an indirect-gap semiconductor absorber layer such as crystalline Si which is less than 20 um thick. We achieve enhancement of the optical absorption from light-trapping that approaches the Yablonovitch limit.

Lee, B. G.; Lin, Y. T.; Sher, M. J.; Mazur, E.; Branz, H. M.

2012-06-01T23:59:59.000Z

465

Biexciton emission from single isoelectronic traps formed by nitrogen-nitrogen pairs in GaAs  

SciTech Connect

We have studied photoluminescence (PL) from individual isoelectronic traps formed by nitrogen-nitrogen (NN) pairs in GaAs. Sharp emission lines due to exciton and biexciton were observed from individual isoelectronic traps in nitrogen atomic-layer doped (ALD) GaAs. The binding energy of biexciton bound to individual isoelectronic traps was approximately 8 meV. Both the exciton and biexciton luminescence lines show completely random polarization and no fine-structure splitting. These results are desirable to the application to the quantum cryptography used in the field of quantum information technology.

Takamiya, Kengo; Fukushima, Toshiyuki; Yagi, Shuhei; Hijikata, Yasuto; Yaguchi, Hiroyuki [Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku , Saitama 338-8570 (Japan); Mochizuki, Toshimitsu; Yoshita, Masahiro; Akiyama, Hidefumi [Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Kuboya, Shigeyuki; Onabe, Kentaro [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Katayama, Ryuji [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2013-12-04T23:59:59.000Z

466

Transport in a harmonic trap: shortcuts to adiabaticity and ultrarobust protocols  

E-Print Network (OSTI)

We study the fast transport of a particle or a Bose-Einstein condensate in a harmonic potential. An exact expression for the final excitation energy in terms of the Fourier transform of the trap acceleration is used to engineer optimal transport protocols (with no final excitation) that are ultra-robust with respect to spring-constant errors. The same technique provides a way to design the simultaneous and robust transport of a few non-interacting species that experience different harmonic trap frequencies in the same trap.

Guéry-Odelin, D

2014-01-01T23:59:59.000Z

467

Transport in a harmonic trap: shortcuts to adiabaticity and ultrarobust protocols  

E-Print Network (OSTI)

We study the fast transport of a particle or a Bose-Einstein condensate in a harmonic potential. An exact expression for the final excitation energy in terms of the Fourier transform of the trap acceleration is used to engineer optimal transport protocols (with no final excitation) that are ultra-robust with respect to spring-constant errors. The same technique provides a way to design the simultaneous and robust transport of a few non-interacting species that experience different harmonic trap frequencies in the same trap.

D. Guéry-Odelin; J. G. Muga

2014-10-18T23:59:59.000Z

468

Photorefractive holography for 2D mechanical vibrations measurement  

Science Journals Connector (OSTI)

We report an efficient holographic setup for the real time measurement of 2D mechanical vibration modes in surfaces, based on the time-average holographic interferometry technique...

de Oliveira, Ivan; Frejlich, Jaime

469

Bubbles trapped on the surface of kidney stones as a cause of the twinkling artifact in ultrasound imaging  

Science Journals Connector (OSTI)

A twinkling artifact (TA) associated with urinary calculi has been described as rapidly changing colors on Doppler ultrasound. The purpose of this study was to investigate the mechanism of TA. Doppler processing was performed on raw per channel radio-frequency data collected when imaging human kidney stones in degassed water. Suppression of twinkling by an ensemble of computer generated replicas of a single received signal demonstrated that the TA arises from variability among the acoustic signals and not from electronic signal processing. This variability was found to be random in nature and its suppression by elevated static pressure and its return when the pressure was released suggests that the presence of surface bubbles on the stone is the mechanism that gives rise to the TA. Submicron size bubbles are often trapped in crevices on solid objects but the presence of these bubbles in vivo is unexpected. To further check this mechanism under conditions identical to in vivo stone-producing porcine kidneys were harvested en bloc with a ligated ureter and then placed into a pressure chamber and imaged at elevated atmospheric pressure. The result was similar to in vitro. [Work supported by NIH DK43881 DK092197 RFBR and NSBRI through NASA NCC 9-58.

Wei Lu; Lawrence Crum

2013-01-01T23:59:59.000Z

470

Bubbles trapped on the surface of kidney stones as a cause of the twinkling artifact in ultrasound imaging  

Science Journals Connector (OSTI)

A twinkling artifact (TA) associated with urinary calculi has been described as rapidly changing colors on Doppler ultrasound. The purpose of this study was to investigate the mechanism of the TA. Doppler processing was performed on raw per channel radio-frequency data collected when imaging human kidney stones in degassed water. Suppression of twinkling by an ensemble of computer generated replicas of a single received signal demonstrated that the TA arises from variability among the acoustic signals and not from electronic signal processing. This variability was found to be random in nature and its suppression by elevated static pressure and its return when the pressure was released suggests that the presence of surface bubbles on the stone is the mechanism of the TA. Submicron size bubbles are often trapped in crevices on solid objects but the presence of these bubbles in vivo is unexpected. To further check this mechanism under conditions identical to in vivo stone-producing porcine kidneys were harvested en bloc with a ligated ureter and then placed into a pressure chamber and imaged at elevated atmospheric pressure. The result was similar to in vitro. Work supported by NIH DK43881 DK092197 RFBR 11-02-01189 12-02-00114 and NSBRI through NASA NCC 9-58.

Oleg Sapozhnikov; Wei Lu; Michael R. Bailey; Peter Kaczkowski; Lawrence A. Crum

2013-01-01T23:59:59.000Z

471

Sideband cooling an ion to the quantum ground state in a Penning trap with very low heating rate  

E-Print Network (OSTI)

We report the laser cooling of a single $^{40}\\text{Ca}^+$ ion in a Penning trap to the motional ground state in one dimension. Cooling is performed in the strong binding limit on the 729-nm electric quadrupole $S_{1/2}\\leftrightarrow D_{5/2}$ transition, broadened by a quench laser coupling the $D_{5/2}$ and $P_{3/2}$ levels. We find the final phonon number to be $\\bar{n}=0.014\\pm0.009$. We measure the heating rate of the trap to be very low with $\\dot{\\bar{n}}=2.5\\pm 0.3\\textrm{s}^{-1}$ and a scaled spectral noise density of $\\omega S_{E}(\\omega)\\sim1.6^{-8}\\textrm{V}^2\\textrm{m}^{-2}\\textrm{Hz}^{-1}\\textrm{s}^{-1}$, which is consistent with the large ion-electrode distance. We perform Rabi oscillations on the sideband-cooled ion and observe a coherence time of $0.7\\pm 0.1\\textrm{ms}$, noting that the practical performance is currently limited by the intensity noise of the probe laser.

J. F. Goodwin; G. Stutter; R. C. Thompson; D. M. Segal

2014-07-23T23:59:59.000Z

472

Certification Framework Based on Effective Trapping for Geologic Carbon Sequestration  

SciTech Connect

We have developed a certification framework (CF) for certifying the safety and effectiveness of geologic carbon sequestration (GCS) sites. Safety and effectiveness are achieved if CO{sub 2} and displaced brine have no significant impact on humans, other living things, resources, or the environment. In the CF, we relate effective trapping to CO{sub 2} leakage risk which takes into account both the impact and probability of leakage. We achieve simplicity in the CF by using (1) wells and faults as the potential leakage pathways, (2) compartments to represent environmental resources that may be impacted by leakage, (3) CO{sub 2} fluxes and concentrations in the compartments as proxies for impact to vulnerable entities, (4) broad ranges of storage formation properties to generate a catalog of simulated plume movements, and (5) probabilities of intersection of the CO{sub 2} plume with the conduits and compartments. We demonstrate the approach on a hypothetical GCS site in a Texas Gulf Coast saline formation. Through its generality and flexibility, the CF can contribute to the assessment of risk of CO{sub 2} and brine leakage as part of the certification process for licensing and permitting of GCS sites around the world regardless of the specific regulations in place in any given country.

Oldenburg, Curtis M.; Bryant, Steven L.; Nicot, Jean-Philippe

2009-01-15T23:59:59.000Z

473

Three-dimensional light trap for reflective particles  

DOE Patents (OSTI)

A system for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focussed beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focussed beams creates a "light cage" and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained.

Neal, Daniel R. (Tijeras, NM)

1999-01-01T23:59:59.000Z

474

Memory effects in the relaxation of the Gaussian trap model  

E-Print Network (OSTI)

We investigate the memory effect in a simple model for glassy relaxation, a trap model with a Gaussian density of states. In this model thermal equilibrium is reached at all finite temperatures and therefore we can consider jumps from low to high temperatures in addition to the quenches usually considered in aging studies. We show that the evolution of the energy following the Kovacs-protocol can approximately be expressed as a difference of two monotonously decaying functions and thus show the existence of a so-called Kovacs hump whenever these functions are not single exponentials. It is well established that the Kovacs effect also occurs in the linear response regime and we show that most of the gross features do not change dramatically when large temperature jumps are considered. However, there is one distinguishing feature that only exists beyond the linear regime which we discuss in detail. For the memory experiment with 'inverted' temperatures, i.e. jumping up and then down again, we find a very similar behavior apart from an opposite sign of the hump.

Gregor Diezemann; Andreas Heuer

2011-02-02T23:59:59.000Z

475

Maximization of permanent trapping of CO{sub 2} and co-contaminants in the highest-porosity formations of the Rock Springs Uplift (Southwest Wyoming): experimentation and multi-scale modeling  

SciTech Connect

Under this project, a multidisciplinary team of researchers at the University of Wyoming combined state-of-the-art experimental studies, numerical pore- and reservoir-scale modeling, and high performance computing to investigate trapping mechanisms relevant to geologic storage of mixed scCO{sub 2} in deep saline aquifers. The research included investigations in three fundamental areas: (i) the experimental determination of two-­?phase flow relative permeability functions, relative permeability hysteresis, and residual trapping under reservoir conditions for mixed scCO{sub 2}-­?brine systems; (ii) improved understanding of permanent trapping mechanisms; (iii) scientifically correct, fine grid numerical simulations of CO{sub 2} storage in deep saline aquifers taking into account the underlying rock heterogeneity. The specific activities included: (1) Measurement of reservoir-­?conditions drainage and imbibition relative permeabilities, irreducible brine and residual mixed scCO{sub 2} saturations, and relative permeability scanning curves (hysteresis) in rock samples from RSU; (2) Characterization of wettability through measurements of contact angles and interfacial tensions under reservoir conditions; (3) Development of physically-­?based dynamic core-­?scale pore network model; (4) Development of new, improved high-­? performance modules for the UW-­?team simulator to provide new capabilities to the existing model to include hysteresis in the relative permeability functions, geomechanical deformation and an equilibrium calculation (Both pore-­? and core-­?scale models were rigorously validated against well-­?characterized core-­? flooding experiments); and (5) An analysis of long term permanent trapping of mixed scCO{sub 2} through high-­?resolution numerical experiments and analytical solutions. The analysis takes into account formation heterogeneity, capillary trapping, and relative permeability hysteresis.

Piri, Mohammad

2014-03-31T23:59:59.000Z

476

Electron Cloud Generation and Trapping in a Quadrupole Magnet at the Los Alamos Proton Storage Ring  

SciTech Connect

Recent beam physics studies on the two-stream e-p instability at the LANL proton storage ring (PSR) have focused on the role of the electron cloud generated in quadrupole magnets where primary electrons, which seed beam-induced multipacting, are expected to be largest due to grazing angle losses from the beam halo. A new diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies using this diagnostic show that the 'prompt' electron flux striking the wall in a quadrupole is comparable to the prompt signal in the adjacent drift space. In addition, the 'swept' electron signal, obtained using the sweeping feature of the diagnostic after the beam was extracted from the ring, was larger than expected and decayed slowly with an exponential time constant of 50 to 100 {micro}s. Other measurements include the cumulative energy spectra of prompt electrons and the variation of both prompt and swept electron signals with beam intensity. Experimental results were also obtained which suggest that a good fraction of the electrons observed in the adjacent drift space for the typical beam conditions in the 2006 run cycle were seeded by electrons ejected from the quadrupole.

Macek, Robert J.; Browman, Andrew A.; Ledford, John E.; /TechSource, Santa Fe /Los Alamos; Borden, Michael J.; O'Hara, James F.; McCrady, Rodney C.; Rybarcyk, Lawrence J.; Spickermann, Thomas; Zaugg, Thomas J.; /Los Alamos; Pivi, Mauro T.F.; /SLAC

2008-03-17T23:59:59.000Z

477

Trapping and Assembly of Living Colloids at Water/Water Interfaces  

E-Print Network (OSTI)

We study the assembly of colloids in a two phase water-water system that provides an environment that can sustain bacteria, providing a new structure with rich potential to confine and structure living colloids. The water-water system, formed via phase separation of a casein and xanthan mixture, forms a 3-D structure of coexisting casein-rich and xanthan-rich phases. Fluorescent labelling and confocal microscopy reveal the attachment of these living colloids, including Escherichia coli and Pseudomonas aeruginosa, at the interface between the two phases. Inert colloids also become trapped at the interfaces, suggesting that the observed attachment can be attributed to capillarity. Over time, these structures coarsen and eventually degrade, illustrating the dynamic nature of these systems. This system lays the foundation for future studies of the interplay of physicochemical properties of the fluid interfaces and bulk phases and microbial responses they provoke to induce complex spatial organization, to study species which occupy distinct niches, and to optimize efficient microbial cross-feeding or protection from competitors.

Sarah D. Hann; Mark Goulian; Daeyeon Lee; Kathleen J. Stebe

2014-12-11T23:59:59.000Z

478

Mechanical and Aerospace Engineering  

E-Print Network (OSTI)

Mechanical and Aerospace Engineering seminar Three Dimensional Traction Force Microscopy with Applications in Cell Mechanics abstract The interactions between biochemical and mechanical signals during-dimensional measurement techniques are needed to investigate the effect of mechanical properties of the substrate

479

Mechanical Engineer Company Description  

E-Print Network (OSTI)

Mechanical Engineer Company Description Control Solutions Inc. is a small, dynamic, and rapidly. Position Description The Mechanical Engineer is responsible for all aspects associated with the mechanical enclosures, brackets, cabling assemblies among others. Systems include mechanisms, sensors, hydraulics, among

Kostic, Milivoje M.

480

MECHANICAL ENGINEERING Ross Schlueter  

E-Print Network (OSTI)

MECHANICAL ENGINEERING Ross Schlueter Engineering Deputy For Mechanical Engineering Russ Wells Mechanical Engineering Department Deputy ELECTRONICS, SOFTWARE & INSTRUMENTATION ENGINEERING Henrik von Der Sen Mechanical Admin. Assist. Joan Wolter Electronics Admin. Assist. Marilyn Wong Division Admin

Note: This page contains sample records for the topic "timing trapping mechanism" 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

Bear Trap Hot Spring Pool & Spa Low Temperature Geothermal Facility | Open  

Open Energy Info (EERE)

Trap Hot Spring Pool & Spa Low Temperature Geothermal Facility Trap Hot Spring Pool & Spa Low Temperature Geothermal Facility Jump to: navigation, search Name Bear Trap Hot Spring Pool & Spa Low Temperature Geothermal Facility Facility Bear Trap Hot Spring Sector Geothermal energy Type Pool and Spa Location Norris, Montana Coordinates 45.5679836°, -111.690808° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}

482

Atom Trap Trace Analysis at ANL | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Atom Trap Trace Analysis at ANL Atom Trap Trace Analysis at ANL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Atom Trap Trace Analysis at ANL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Atom Trap Trace Analysis (ATTA) to determine isotopic abundances. Developed at: Argonne National Laboratory Developed in: 1999-current

483

A 674 nm external cavity diode laser for a ??Sr? ion trap  

E-Print Network (OSTI)

Atomic ion traps are a promising candidate for scalable quantum information processing. In this thesis, a 674 nm extended cavity diode laser is built to address an optical quantum bit in ??Sr? with the goal of testing such ...

Thon, Susanna M. (Susanna Mitrani)

2005-01-01T23:59:59.000Z

484

Trapping and excitation of modes in the magnetotail Katharine J. Mills and Andrew N. Wrighta)  

E-Print Network (OSTI)

Trapping and excitation of modes in the magnetotail Katharine J. Mills and Andrew N. Wrighta wind speed, Dungey obtained a value of about 1000 RE for the length of the magnetotail. Magnetometer

Wright, Andrew N.

485

Analysis of mineral trapping for CO2 disposal in deep aquifers  

E-Print Network (OSTI)

of Mineral Trapping for CO2 Disposal in Deep Aquifers Tianfue~mail: Tianfu Xu@lbl. gov) CO2 disposal into deep aquiferspermit significant sequestration of CO2. We performed batch

Xu, Tianfu

2014-01-01T23:59:59.000Z

486

Study of electron trapping by a transversely ellipsoidal bubble in the laser wake-field acceleration  

SciTech Connect

We present electron trapping in an ellipsoidal bubble which is not well explained by the spherical bubble model by [Kostyukov et al., Phys. Rev. Lett. 103, 175003 (2009)]. The formation of an ellipsoidal bubble, which is elongated transversely, frequently occurs when the spot size of the laser pulse is large compared to the plasma wavelength. First, we introduce the relation between the bubble size and the field slope inside the bubble in longitudinal and transverse directions. Then, we provide an ellipsoidal model of the bubble potential and investigate the electron trapping condition by numerical integration of the equations of motion. We found that the ellipsoidal model gives a significantly less restrictive trapping condition than that of the spherical bubble model. The trapping condition is compared with three-dimensional particle-in-cell simulations and the electron trajectory in test potential simulations.

Cho, Myung-Hoon [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of); Kim, Young-Kuk; Hur, Min Sup [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

2013-09-15T23:59:59.000Z

487

EXPERIMENTAL RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-l  

E-Print Network (OSTI)

P.A. Pincosy, A Toroidal Plasma Gun, 11 LBL-9507, (1979),RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-~1* P. A.further work on the higher gun p13sma energy may lead to

Pincosy, P.A.

2012-01-01T23:59:59.000Z

488

Phase slippage and self-trapping in a self-induced bosonic Josephson junction  

SciTech Connect

A dipolar condensate confined in a toroidal trap constitutes a self-induced Josephson junction when the dipoles are oriented perpendicularly to the trap symmetry axis and the s-wave scattering length is small enough. The ring-shaped double-well potential coming from the anisotropic character of the mean-field dipolar interaction is robust enough to sustain self-trapping dynamics, which takes place when the initial population imbalance between the two wells is large. We show that, in this system, the self-trapping regime is directly related to a vortex-induced phase-slip dynamics. A vortex and antivortex are spontaneously nucleated in the low-density regions before a minimum of the population imbalance is reached and then cross the toroidal section in opposite directions through the junctions. This vortex dynamics yields a phase slip between the two weakly linked condensates causing an inversion of the particle flux.

Abad, M.; Guilleumas, M.; Mayol, R.; Pi, M. [Departament d'Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, E-08028 Barcelona (Spain); Jezek, D. M. [IFIBA-CONICET and Departamento de Fisica, FCEN-UBA Pabellon 1, Ciudad Universitaria, 1428 Buenos Aires (Argentina)

2011-09-15T23:59:59.000Z

489

Poly(vinyl alcohol)-based buffering membranes for isoelectric trapping separations  

E-Print Network (OSTI)

Isoelectric trapping (IET) in multicompartment electrolyzers (MCE) has been widely used for the electrophoretic separation of ampholytic compounds such as proteins. In IET, the separation occurs in the buffering membranes that form a step-wise p...

Craver, Helen C.

2009-05-15T23:59:59.000Z

490

Phase-slippage and self-trapping in a self-induced bosonic Josephson junction  

E-Print Network (OSTI)

A dipolar condensate confined in a toroidal trap constitutes a self-induced Josepshon junction when the dipoles are oriented perpendicularly to the trap symmetry axis and the s-wave scattering length is small enough. The ring-shaped double-well potential coming from the anisotropic character of the mean-field dipolar interaction is robust enough to sustain self-trapping dynamics, which takes place when the initial population imbalance between the two wells is large. We show that in this system the self-trapping regime is directly related to a vortex-induced phase-slip dynamics. A vortex and antivortex are spontaneously nucleated in the low density regions, before a minimum of the population imbalance is reached, and then cross the toroidal section in opposite directions through the junctions.This vortex dynamics yields a phase slip between the two weakly linked condensates causing an inversion of the particle flux.

Abad, M; Mayol, R; Pi, M; Jezek, D M

2011-01-01T23:59:59.000Z

491

137Cs Trapped by Biomass within 20 km of the Fukushima Daiichi Nuclear Power Plant  

Science Journals Connector (OSTI)

137Cs Trapped by Biomass within 20 km of the Fukushima Daiichi Nuclear Power Plant ... † Department of Health and Environmental Sciences, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan ...

Akio Koizumi; Tamon Niisoe; Kouji H. Harada; Yukiko Fujii; Ayumu Adachi; Toshiaki Hitomi; Hirohiko Ishikawa

2013-07-26T23:59:59.000Z

492

Influence of the Radio-Frequency source properties on RF-based atom traps  

Science Journals Connector (OSTI)

We discuss the quality required for the RF source used to trap neutral atoms in RF-dressed potentials. We illustrate this discussion with experimental results obtained on a Bose-Einstein condensation experimen...

O. Morizot; L. Longchambon; R. Kollengode Easwaran…

2008-04-01T23:59:59.000Z

493

The Dissipation of Trapped Lee Waves. Part I: Leakage of Inviscid Waves into the Stratosphere  

Science Journals Connector (OSTI)

Leaky trapped mountain lee waves are investigated by examining the structure of individual linear modes in multilayer atmospheres. When the static stability and cross-mountain wind speed are constant in the topmost unbounded layer, modes that ...

Dale R. Durran; Matthew O. G. Hills; Peter N. Blossey

494

Efficient Light Trapping in Inverted Nanopyramid Thin Crystalline Silicon Membranes for Solar Cell Applications  

E-Print Network (OSTI)

Thin-film crystalline silicon (c-Si) solar cells with light-trapping structures can enhance light absorption within the semiconductor absorber layer and reduce material usage. Here we demonstrate that an inverted nanopyramid ...

Mavrokefalos, Anastassios

495

An injection-locked 674 nm laser for Strontium-88 ion trapping  

E-Print Network (OSTI)

Energy levels of the valence electron of a single trapped ??Sr+ ion can be harnessed as an effective qubit for quantum information processing. The qubit transition to a metastable energy state can be stimulated by a laser ...

Katz, Rena J. (Rena Jenelle)

2012-01-01T23:59:59.000Z

496

WAVELENGTH DEPENDENT EFFECTIVE TRAP DENSITY IN CdTe : EVIDENCE FOR THE PRESENCE OF TWO  

E-Print Network (OSTI)

1 WAVELENGTH DEPENDENT EFFECTIVE TRAP DENSITY IN CdTe : EVIDENCE FOR THE PRESENCE OF TWO.1016/S0030-4018(96)00516-0 #12;2 Photorefractive semiconductors like CdTe are characterized by a low

497

Molecular-bond hardening and dynamics of molecular stabilization and trapping in intense laser pulses  

E-Print Network (OSTI)

stabilization and population trapping of high-lying vibrational states and chemical bond hardening are predicted for both continuous-wave (cw) lasers and short laser pulses. While the intensity dependences of the laser-induced stabilization are essentially...

Yao, Guanhua; Chu, Shih-I

1993-07-01T23:59:59.000Z

498

Engineering optical traps for new environments and applications in the measurement of biological adhesives and motors  

E-Print Network (OSTI)

Optical traps have played a central role in the exploration of biological systems through the examination of molecular motors, biopolymers, and many other interactions at the nano and micro length scales. This thesis seeks ...

Appleyard, David Collins

2009-01-01T23:59:59.000Z

499

Optical Trapping Platform Based on Highly Confining Silicon Waveguiding Structures with Microfluidics  

Science Journals Connector (OSTI)

We demonstrate strongly enhanced optical trapping forces on sub-micron-diameter dielectric spheres within a pressure-driven microfluidic flow of several hundred microns/s using the...

Schmidt, Bradley; Manipatruni, Sasikanth; Yang, Allen H; Erickson, David; Lipson, Michal

500

Quantum state engineering for multiple hot trapped ions in the symmetric Dicke subspace  

Science Journals Connector (OSTI)

We propose a scheme for the generation of an arbitrary quantum states for multiple trapped ions in the symmetric Dicke subspace. One can manipulate the collective ion transition in a selective symmetric Dicke ...

S. B. Zheng

2009-09-01T23:59:59.000Z