Sample records for bubble chamber tracks

  1. SciTech Connect: ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS

    Office of Scientific and Technical Information (OSTI)

    THE ANALYSIS OF BUBBLE CHAMBER TRACKS Citation Details In-Document Search Title: ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS Since its invention by Glaser in 1953, the bubble...

  2. Neutron Detection via Bubble Chambers

    SciTech Connect (OSTI)

    Jordan, David V.; Ely, James H.; Peurrung, Anthony J.; Bond, Leonard J.; Collar, J. I.; Flake, Matthew; Knopf, Michael A.; Pitts, W. K.; Shaver, Mark W.; Sonnenschein, Andrew; Smart, John E.; Todd, Lindsay C.

    2005-10-06T23:59:59.000Z

    The results of a Pacific Northwest National Laboratory (PNNL) exploratory research project investigating the feasibility of fast neutron detection using a suitably prepared and operated, pressure-cycled bubble chamber are described. The research was conducted along two parallel paths. Experiments with a slow pressure-release Halon chamber at the Enrico Fermi Institute at the University of Chicago showed clear bubble nucleation sensitivity to an AmBe neutron source and insensitivity to the 662 keV gammas from a 137Cs source. Bubble formation was documented via high-speed (1000 frames/sec) photography, and the acoustic signature of bubble formation was detected using a piezo-electric transducer element mounted on the base of the chamber. The chamber’s neutron sensitivity as a function of working fluid temperature was mapped out. The second research path consisted of the design, fabrication, and testing of a fast pressure-release Freon-134a chamber at PNNL. The project concluded with successful demonstrations of the PNNL chamber’s AmBe neutron source sensitivity and 137Cs gamma insensitivity. The source response tests of the PNNL chamber were documented with high-speed photography.

  3. Direct Measurement of the Bubble Nucleation Energy Threshold in a CF3I Bubble Chamber

    E-Print Network [OSTI]

    Behnke, E; Brice, S J; Broemmelsiek, D; Collar, J I; Cooper, P S; Crisler, M; Dahl, C E; Fustin, D; Hall, J; Harnish, C; Levine, I; Lippincott, W H; Moan, T; Nania, T; Neilson, R; Ramberg, E; Robinson, A E; Sonnenschein, A; Vázquez-Jáuregui, E; Rivera, R A; Uplegger, L

    2013-01-01T23:59:59.000Z

    We have directly measured the energy threshold and efficiency for bubble nucleation from iodine recoils in a CF3I bubble chamber in the energy range of interest for a dark matter search. These interactions cannot be probed by standard neutron calibration methods, so we develop a new technique by observing the elastic scattering of 12 GeV/c negative pions. The pions are tracked with a silicon pixel telescope and the reconstructed scattering angle provides a measure of the nuclear recoil kinetic energy. The bubble chamber was operated with a nominal threshold of (13.6+-0.6) keV. Interpretation of the results depends on the response to fluorine and carbon recoils, but in general we find agreement with the predictions of the classical bubble nucleation theory. This measurement confirms the applicability of CF3I as a target for spin-independent dark matter interactions and represents a novel technique for calibration of superheated fluid detectors.

  4. The hydrogen bubble chamber and the strange resonances

    SciTech Connect (OSTI)

    Alvarez, L.W.

    1985-06-01T23:59:59.000Z

    The author's recollections of his experience in the use of bubble chambers and the discoveries of strange resonances are given. (LEW)

  5. Reanalysis of bubble chamber measurements of muon-neutrino induced single pion production

    E-Print Network [OSTI]

    Callum Wilkinson; Philip Rodrigues; Susan Cartwright; Lee Thompson; Kevin McFarland

    2014-11-17T23:59:59.000Z

    There exists a longstanding disagreement between bubble chamber measurements of the single pion production channel $\

  6. Dark matter limits froma 15 kg windowless bubble chamber

    SciTech Connect (OSTI)

    Szydagis, Matthew Mark; /Chicago U.

    2010-12-01T23:59:59.000Z

    The COUPP collaboration has successfully used bubble chambers, a technology previously applied only to high-energy physics experiments, as direct dark matter detectors. It has produced the world's most stringent spin-dependent WIMP limits, and increasingly competitive spin-independent limits. These limits were achieved by capitalizing on an intrinsic rejection of the gamma background that all other direct detection experiments must address through high-density shielding and empirically-determined data cuts. The history of COUPP, including its earliest prototypes and latest results, is briefly discussed in this thesis. The feasibility of a new, windowless bubble chamber concept simpler and more inexpensive in design is discussed here as well. The dark matter limits achieved with a 15 kg windowless chamber, larger than any previous COUPP chamber (2 kg, 4 kg), are presented. Evidence of the greater radiopurity of synthetic quartz compared to natural is presented using the data from this 15 kg device, the first chamber to be made from synthetic quartz. The effective reconstruction of the three-dimensional positions of bubbles in a highly distorted optical field, with ninety-degree bottom lighting similar to cloud chamber lighting, is demonstrated. Another innovation described in this thesis is the use of the sound produced by bubbles recorded by an array of piezoelectric sensors as the primary means of bubble detection. In other COUPP chambers, cameras have been used as the primary trigger. Previous work on bubble acoustic signature differentiation using piezos is built upon in order to further demonstrate the ability to discriminate between alpha- and neutron-induced events.

  7. Invention and History of the Bubble Chamber (LBNL Summer Lecture Series)

    ScienceCinema (OSTI)

    Glaser, Don

    2011-04-28T23:59:59.000Z

    Summer Lecture Series 2006: Don Glaser won the 1960 Nobel Prize for Physics for his 1952 invention of the bubble chamber at Berkeley Lab, a type of particle detector that became the mainstay of high-energy physics research throughout the 1960s and 1970s. He discusses how, inspired by bubbles in a glass of beer, he invented the bubble chamber and detected cosmic-ray muons.

  8. Optical Alignment System for the PHENIX Muon Tracking Chambers

    E-Print Network [OSTI]

    J. Murata; A. Al-Jamel; R. L. Armendariz; M. L. Brooks; T. Horaguchi; N. Kamihara; H. Kobayashi; D. M. Lee; T. -A. Shibata; W. E. Sondheim

    2002-12-26T23:59:59.000Z

    A micron-precision optical alignment system (OASys) for the PHENIX muon tracking chambers is developed. To ensure the required mass resolution of vector meson detection, the relative alignment between three tracking station chambers must be monitored with a precision of 25$\\mu$m. The OASys is a straightness monitoring system comprised of a light source, lens and CCD camera, used for determining the initial placement as well as for monitoring the time dependent movement of the chambers on a micron scale.

  9. Acoustic studies for alpha background rejection in dark matter bubble chamber detectors

    SciTech Connect (OSTI)

    Bou-Cabo, M.; Felis, I.; Ardid, M.; Collaboration: COUPP Collaboration

    2013-08-08T23:59:59.000Z

    COUPP (Chicagoland Observatory for Underground Particle Physics) is an experiment with bubble chambers able to detect dark matter directly either with Spin-Dependent or with Spin-Independent interactions. The target material is a superheated liquid (usually CF3I) that can be bubble nucleated due to nuclear recoils produced by elastic collisions of dark matter particles. The bubble growth inside the chamber is accompanied with an acoustic signature. The acoustic technique has been successfully used to have a good alpha discrimination (about 99%). In this paper, we present different studies and results related with the characterization of the acoustic properties of the detector and the different phenomena involved in the acoustic measurements of the bubble growth, such as sound generation, sound transmission and optimization of piezoelectric transducers.

  10. Novel Electron-Bubble Tracking Detectors

    SciTech Connect (OSTI)

    Willis, William J.

    2008-08-08T23:59:59.000Z

    Our Columbia group, in collaboration with Brookhaven and SMU, has been carrying out R&D on tracking detectors in cryogenic liquids, including neon and helium. A cryostat purchased by this Grant capable of working temperatures down to 1 K and pressures above the critical point of neon and helium has been operated with a variety of noble fluids. Gaseous Electron Multipliers (GEM) with hydrogen additives have been operated with tracks of radioactive sources read out both by electrical charge detecting electronics, and an optical camera purchased by this Grant, measuring mobility, charge yield, transitions through phase boundaries, gain limitations, and other properties. The goal is very high resolution in large volumes. The scope of the project is the provision of a high performance camera and its installation in a cryogenic facility providing pressure up to 40 atmospheres and a temperature from ambient down to about 1 K. In this section we will address the goals and results having to do with this project and particularly the performance of the camera, and provide a summary of the status of the detector project. The technical development of digital cameras has been dominated for the last forty years by the Charge-Coupled Device technology (CCD). This allows photon recording on very small pixels on silicon planes that provide high quantum efficiency in the visible spectrum, recording the charge generated by a single photon stored on one pixel with an area of order ten microns square. The area can be up to several centimeters squared, containing a million pixels or more. The stores charge is usually read out by manipulating voltage biases to shift the charge in each pixel over to the next, and eventually out of the array and sent to an external processor and memory. Mass production has brought the cost per channel down to very small values and allowed cameras to be integrated to many consumer products. Thermal noise becomes larger than one photon on a single pixel at good temperature, and demand night vision and other demanding applications has led to intense R&D over the years, and small coolers that maintain the CCD at temperatures of more than 100K below ambient are integrated into the camera package. These systems are sold in quantity to amateur astronomers with the same silicon devices used in professional systems, provided long exposure times with less than one electron noise per pixel. In our particle readout, we are imaging a three-dimensional track drifting into the readout plane over time, and we need to read out one plane after another, and we need a high rate of pixel processing. For many years, the noise in the electronic amplifier matching the CCD to the external electronics led to noise levels of many electrons, much higher than in the CCD itself. A break-through was made by providing signal gain inside the CCD, connecting to the external line, by a Electron Multiplier CCD, using a number of electron avalanche stages, each with a small, stable gain. This device was brought out just before out application for the present Grant, provided the last link in the development chain, which allowed out optical readout concept to be implemented at reason fact. In fact, we profited from the falling cost by delaying our order for about a year, which, together with the university discount, allowed us to proceed within our budget. The camera we purchase from the firm ANDOR, which introduced the technique, comes with an extensive suite of software that allows the fast readout with different integration times, and makes a very convenient use in our application. We have been able to make images of the light signals coming from out GEM electron avalanche detectors under many conditions, with tracks of different particle types. We have reconfigured the system a number of times, using the results from the camera to learn how to change the TPC drift geometry and the GEM charge amplifier to improve performance, a process that is still going on. The camera purchase with this Grant has performed reliably and just as specified b

  11. COUPP - a search for dark matter with a continuously sensitive bubble chamber

    SciTech Connect (OSTI)

    Collar, Juan,; Crum, Keith; Mishra, Smriti; Nakazawa, Dante; Odom, Brian; Rasmussen, Julia; Riley, Nathan; Szydagis, Matthew; /Chicago U.; Behnke, Ed; Levine, Ilan; Vander Werf, Nate; /Indiana U., South Bend; Cooper, Peter; Crisler, Mike; Hu, Martin; Ramberg, Erik; Sonnenschein, Andrew; Tschirhart, Robert; /Fermilab

    2007-01-01T23:59:59.000Z

    We propose to construct and operate a 60-kg room temperature CF{sub 3}I bubble chamber as a prototype dark matter (WIMP) detector. Operating in weakly-superheated mode, the chamber will be sensitive to WIMP induced nuclear recoils above 10 keV, while rejecting background electron recoils at a level approaching 10{sup 10}. We would first commission and operate this chamber in the MINOS near detector hall with the goal to demonstrate stable operation and measure internal contamination and any other backgrounds. This chamber, or an improved version, would then be relocated to an appropriate deep underground site such as the Soudan Mine. This detector will have unique sensitivity to spin-dependent WIMP-nucleon couplings, and even in this early stage of development will attain competitive sensitivity to spin-independent couplings.

  12. A Proposal to Operate the COUPP-60 Bubble Chamber at SNOLAB

    SciTech Connect (OSTI)

    Collar, Juan; Dahl, C.Eric; Fustin, Drew; Goetzke, Luke; Riley, Nathan; Schimmelpfennig, Hannes; Szydagis, Matthew; /KICP, Chicago; Behnke, Ed; Hinnefeld, Henry; Levine, Ilan; Palenchar, Andrea; /Indiana U., South Bend /Fermilab

    2009-08-01T23:59:59.000Z

    Bubble chambers are promising devices for the detection of WIMP dark matter, due to their easy scalability to large target masses and insensitivity to background {gamma} and {beta} radiation. The COUPP collaboration has constructed small chambers which have achieved competitive sensitivity for spin-dependent WIMP-nucleon scattering. A new chamber, COUPP-60, containing 60-kg of CF{sub 3}I target liquid, has been built and is being commissioned at Fermilab. We propose to move this detector to SNOLAB after completing tests in a shallow underground site at Fermilab. At SNOLAB, we expect the sensitivity of the experiment to be determined by the level of {alpha}emitting contamination in the target liquid. If we achieve state-of-the-art levels of {alpha} emitting contamination, we will improve current sensitivity by approximately four orders of magnitude beyond our published limits, to the region of 10{sup -4} pb for a 30 GeV WIMP interacting by spin-dependent couplings to the proton. This will allow a first exploration of the phase space favored by supersymmetric models in this regime.

  13. A Proposal for a Ton Scale Bubble Chamber for Dark Matter Detection

    SciTech Connect (OSTI)

    Collar, Juan; Dahl, C.Eric; Fustin, Drew; Robinson, Alan; /Chicago U.; Behnke, Ed; Behnke, Joshua; Breznau, William; Connor, Austin; Kuehnemund, Emily Grace; Levine, Ilan; Moan, Timothy; /Indiana U., South Bend /Fermilab

    2010-10-07T23:59:59.000Z

    The nature of non-baryonic dark matter is one of the most intriguing questions for particle physics at the start of the 21st century. There is ample evidence for its existence, but almost nothing is known of its properties. WIMPs are a very appealing candidate particle and several experimental campaigns are underway around the world to search for these particles via the nuclear recoils that they should induce. The COUPP series of bubble chambers has played a significant role in the WIMP search. Through a sequence of detectors of increasing size, a number of R&D issues have arisen and been solved, and the technology has now been advanced to the point where the construction of large chambers requires a modest research effort, some development, but mostly just engineering. It is within this context that we propose to build the next COUPP detector - COUPP-500, a ton scale device to be built over the next three years at Fermilab and then deployed deep underground at SNOLAB. The primary advantages of the COUPP approach over other technologies are: (1) The ability to reject electron and gamma backgrounds by arranging the chamber thermodynamics such that these particles do not even trigger the detector. (2) The ability to suppress neutron backgrounds by having the radioactively impure detection elements far from the active volume and by using the self-shielding of a large device and the high granularity to identify multiple bubbles. (3) The ability to build large chambers cheaply and with a choice of target fluids. (4) The ability to increase the size of the chambers without changing the size or complexity of the data acquisition. (5) Sensitivity to spin-dependent and spin-independent WIMP couplings. These key advantages should enable the goal of one background event in a ton-year of exposure to be achieved. The conceptual design of COUPP-500 is scaled from the preceding devices. In many cases all that is needed is a simple scaling up of components previously used. Calibration and R&D are still needed on some aspects of the system. We know we have the ability to distinguish alpha-induced events from nuclear recoils, but we do not yet know whether the combination of material purity and rejection are good enough to run for a year with no alpha background. We also need to have more detailed measurements of the detector threshold and a better understanding of its high gamma rejection. In addition, there are important checks to make on the longevity of the detector components in the hydraulic fluid and on the chemistry of the active fluid. The 2009 PASAG report explicitly supported the construction of the COUPP-500 device in all funding scenarios. The NSF has shown similar enthusiasm. It awarded one of its DUSEL S4 grants to assist in the engineering needed to build COUPP-500. The currently estimated cost of COUPP-500 is $8M, about half the $15M-$20M price tag expected by the PASAG report for a next generation dark matter search experiment. The COUPP-500 device will have a spin independent WIMP-nucleus cross-section sensitivity of 6 x 10{sup -47} cm{sup 2} after a background-free year of running. This device should then provide the benchmark against which all other WIMP searches are measured.

  14. A sun-tracking environmental chamber for the outdoor quantification of CPV modules

    SciTech Connect (OSTI)

    Faiman, David, E-mail: faiman@bgu.ac.il; Melnichak, Vladimir, E-mail: faiman@bgu.ac.il; Bokobza, Dov, E-mail: faiman@bgu.ac.il; Kabalo, Shlomo, E-mail: faiman@bgu.ac.il [Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000 (Israel)

    2014-09-26T23:59:59.000Z

    The paper describes a sun-tracking environmental chamber and its associated fast electronics, devised for the accurate outdoor characterization of CPV cells, receivers, mono-modules, and modules. Some typical measurement results are presented.

  15. Bubbly Flow Experiment in Channel Using an Optical Probe and Tracking Algorithm

    E-Print Network [OSTI]

    Khan, Abdul

    2012-10-19T23:59:59.000Z

    was inserted through a porous media at three superficial gas velocities: 4.6 mm/s, 2.5 mm/s, and 1.4 mm/s. Two techniques were applied in the experiment to measure the bubbly flow: an optical probe and an in-house developed tracking algorithm. Measurements...

  16. First Dark Matter Search Results from a 4-kg CF$_3$I Bubble Chamber Operated in a Deep Underground Site

    SciTech Connect (OSTI)

    Behnke, E.; /Indiana U., South Bend; Behnke, J.; /Indiana U., South Bend; Brice, S.J.; /Fermilab; Broemmelsiek, D.; /Fermilab; Collar, J.I.; /Chicago U., EFI; Conner, A.; /Indiana U., South Bend; Cooper, P.S.; /Fermilab; Crisler, M.; /Fermilab; Dahl, C.E.; /Chicago U., EFI; Fustin, D.; /Chicago U., EFI; Grace, E.; /Indiana U., South Bend /Fermilab

    2012-04-01T23:59:59.000Z

    New data are reported from the operation of a 4.0 kg CF{sub 3}I bubble chamber in the 6800 foot deep SNOLAB underground laboratory. The effectiveness of ultrasound analysis in discriminating alpha decay background events from single nuclear recoils has been confirmed, with a lower bound of >99.3% rejection of alpha decay events. Twenty single nuclear recoil event candidates and three multiple bubble events were observed during a total exposure of 553 kg-days distributed over three different bubble nucleation thresholds. The effective exposure for single bubble recoil-like events was 437.4 kg-days. A neutron background internal to the apparatus, of known origin, is estimated to account for five single nuclear recoil events and is consistent with the observed rate of multiple bubble events. This observation provides world best direct detection constraints on WIMP-proton spin-dependent scattering for WIMP masses >20 GeV/c{sup 2} and demonstrates significant sensitivity for spin-independent interactions.

  17. Determination of astrophysical thermonuclear rates with a bubble chamber: The {sup 12}C(??){sup 16}O reaction case

    SciTech Connect (OSTI)

    DiGiovine, B.; Henderson, D.; Holt, R. J.; Rehm, K. E. [Argonne National Laboratory, Argonne IL 60439 (United States); Grames, J.; Meekins, D.; Poelker, M.; Suleiman, R. [Jefferson Lab, Newport News, VA 23606 (United States); Robinson, A.; Ugalde, C., E-mail: cugalde@uchicago.edu [University of Chicago, Chicago, IL 60637 (United States); Sonnenschein, A. [Fermilab, Batavia, IL 60510 (United States)

    2013-11-07T23:59:59.000Z

    The {sup 12}C(??){sup 16}O reaction rate is considered one of the most important unknown parameters in the physics of structure and evolution of massive stars. While extensive experimental campaigns have been performed trying to improve the quality of the measurements, the rate still holds very large uncertainties. Here we discuss a new experimantal scheme to measure the cross section of this reaction with a bubble chamber and a bremsstrahlung beam. The main advantage of the technique is a gain in the luminosity of several orders of magnitude when compared to other ongoing experiments.

  18. Photoelectron track length distributions measured in a negative ion time projection chamber

    E-Print Network [OSTI]

    Prieskorn, Z R; Kaaret, P E; Black, J K

    2014-01-01T23:59:59.000Z

    We report photoelectron track length distributions between 3 and 8 keV in gas mixtures of Ne+CO2+CH3NO2 (260:80:10 Torr) and CO2+CH3NO2 (197.5: 15 Torr). The measurements were made using a negative ion time projection chamber (NITPC) at the National Synchrotron Light Source (NSLS) at the Brookhaven National Laboratory (BNL). We report the first quantitative analysis of photoelectron track length distributions in a gas. The distribution of track lengths at a given energy is best fit by a lognormal distribution. A powerlaw distribution of the form, f(E)=a(E/Eo)n, is found to fit the relationship between mean track length and energy. We find n=1.29 +/- 0.07 for Ne+CO2+CH3NO2 and n=1.20 +/- 0.09 for CO2+CH3NO2. Understanding the distribution of photoelectron track lengths in proportional counter gases is important for optimizing the pixel size and the dimensions of the active region in electron-drift time projection chambers (TPCs) and NITPC X-ray polarimeters.

  19. Improved Limits on Spin-Dependent WIMP-Proton Interactions from a Two Liter CF{sub 3}I Bubble Chamber

    SciTech Connect (OSTI)

    Behnke, E.; Behnke, J.; Hinnefeld, J. H.; Levine, I.; Shepherd, T. [Indiana University South Bend, South Bend, Indiana (United States); Brice, S. J.; Broemmelsiek, D.; Cooper, P. S.; Crisler, M.; Hall, J.; Hu, M.; Ramberg, E.; Sonnenschein, A. [Fermi National Accelerator Laboratory, Batavia, Illinois (United States); Collar, J. I.; Dahl, C. E.; Fustin, D.; Szydagis, M. [Enrico Fermi Institute, KICP and Department of Physics, University of Chicago, Chicago, Illinois (United States)

    2011-01-14T23:59:59.000Z

    Data from the operation of a bubble chamber filled with 3.5 kg of CF{sub 3}I in a shallow underground site are reported. An analysis of ultrasound signals accompanying bubble nucleations confirms that alpha decays generate a significantly louder acoustic emission than single nuclear recoils, leading to an efficient background discrimination. Three dark matter candidate events were observed during an effective exposure of 28.1 kg day, consistent with a neutron background. This observation provides strong direct detection constraints on weakly interacting massive particle (WIMP)-proton spin-dependent scattering for WIMP masses >20 GeV/c{sup 2}.

  20. In-Jet Tracking Efficiency Analysis for the STAR Time Projection Chamber in Polarized Proton-Proton Collisions at sqrt(s) = 200GeV 

    E-Print Network [OSTI]

    Huo, Liaoyuan

    2012-07-16T23:59:59.000Z

    As one of the major mid-rapidity tracking devices of the STAR detector at the Relativistic Heavy-Ion Collider (RHIC), the Time Projection Chamber (TPC) plays an important role in measuring trajectory and energy of high energy charged particles...

  1. In-Jet Tracking Efficiency Analysis for the STAR Time Projection Chamber in Polarized Proton-Proton Collisions at sqrt(s) = 200GeV

    E-Print Network [OSTI]

    Huo, Liaoyuan

    2012-07-16T23:59:59.000Z

    As one of the major mid-rapidity tracking devices of the STAR detector at the Relativistic Heavy-Ion Collider (RHIC), the Time Projection Chamber (TPC) plays an important role in measuring trajectory and energy of high energy charged particles...

  2. The Bonus Detector: A Radial Time Projection Chamber for tracking Spectator Protons

    SciTech Connect (OSTI)

    Howard Fenker

    2004-01-25T23:59:59.000Z

    A GEM-based Radial Time Projection Chamber is being developed as a spectator-proton tracker for an experiment at Jefferson Lab. The purpose of the experiment is the study of the structure of nearly free neutrons. Interactions on such neutrons can be identified by the presence of a backward-moving proton in the final state of a beam-deuterium collision. The detector must be of very low mass in order to provide sensitivity to the slowest possible protons. The ionization electron trail left by the protons will drift radially outward to an amplification structure composed of curved GEMs, and the resulting charge will be collected on pads on the outer layer of the detector. Unique design challenges are imposed by the cylindrical geometry and the low mass requirement. The status of the project and results of prototype tests are presented.

  3. Characteristics of a radon diffusion chamber with electrical collection using plastic nuclear track detectors. Open file report 31 August 1982-30 November 1983

    SciTech Connect (OSTI)

    Frank, A.L.; Benton, E.V.

    1982-09-01T23:59:59.000Z

    A portable radon diffusion chamber was tested with electrical collection of radon daughter nuclei for enhancement of sensitivity. The detector was small enough to be worn suspended from a belt. With a battery-supplied high voltage, the sensitivity was found to be 1.43 tracks/sq cm per pCi-h/lambda of ambient radon at 50% relative humidity. The track densities on the surfaces of the CR-39 plastic nuclear track detectors were found to be nonuniform, making the determination of average densities with high accuracy difficult. The fabrication of electrets for use in the detector was investigated in accordance with published techniques with negative results.

  4. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  5. Bubble diagnostics

    DOE Patents [OSTI]

    Visuri, Steven R. (Livermore, CA); Mammini, Beth M. (Walnut Creek, CA); Da Silva, Luiz B. (Danville, CA); Celliers, Peter M. (Berkeley, CA)

    2003-01-01T23:59:59.000Z

    The present invention is intended as a means of diagnosing the presence of a gas bubble and incorporating the information into a feedback system for opto-acoustic thrombolysis. In opto-acoustic thrombolysis, pulsed laser radiation at ultrasonic frequencies is delivered intraluminally down an optical fiber and directed toward a thrombus or otherwise occluded vessel. Dissolution of the occlusion is therefore mediated through ultrasonic action of propagating pressure or shock waves. A vapor bubble in the fluid surrounding the occlusion may form as a result of laser irradiation. This vapor bubble may be used to directly disrupt the occlusion or as a means of producing a pressure wave. It is desirable to detect the formation and follow the lifetime of the vapor bubble. Knowledge of the bubble formation and lifetime yields critical information as to the maximum size of the bubble, density of the absorbed radiation, and properties of the absorbing material. This information can then be used in a feedback system to alter the irradiation conditions.

  6. Exposure chamber

    DOE Patents [OSTI]

    Moss, Owen R. (Kennewick, WA)

    1980-01-01T23:59:59.000Z

    A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

  7. The Mark II Vertex Drift Chamber

    SciTech Connect (OSTI)

    Alexander, J.P.; Baggs, R.; Fujino, D.; Hayes, K.; Hoard, C.; Hower, N.; Hutchinson, D.; Jaros, J.A.; Koetke, D.; Kowalski, L.A.

    1989-03-01T23:59:59.000Z

    We have completed constructing and begun operating the Mark II Drift Chamber Vertex Detector. The chamber, based on a modified jet cell design, achieves 30 {mu}m spatial resolution and <1000 {mu}m track-pair resolution in pressurized CO{sub 2} gas mixtures. Special emphasis has been placed on controlling systematic errors including the use of novel construction techniques which permit accurate wire placement. Chamber performance has been studied with cosmic ray tracks collected with the chamber located both inside and outside the Mark II. Results on spatial resolution, average pulse shape, and some properties of CO{sub 2} mixtures are presented. 10 refs., 12 figs., 1 tab.

  8. Ionization chamber

    DOE Patents [OSTI]

    Walenta, Albert H. (Port Jefferson Station, NY)

    1981-01-01T23:59:59.000Z

    An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

  9. The TESLA Time Projection Chamber

    E-Print Network [OSTI]

    Nabil Ghodbane

    2002-12-12T23:59:59.000Z

    A large Time Projection Chamber is proposed as part of the tracking system for a detector at the TESLA electron positron linear collider. Different ongoing R&D studies are reviewed, stressing progress made on a new type readout technique based on Micro-Pattern Gas Detectors.

  10. Target Chamber

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafety Tag:8, 2013 FINALTarget Chamber The

  11. Temperature Studies for ATLAS MDT BOS Chambers

    E-Print Network [OSTI]

    A. Engl; O. Biebel; R. Hertenberger; R. Mameghani; D. Merkl; F. Rauscher; D. Schaile; R. Stroehmer

    2009-08-11T23:59:59.000Z

    Data sets with high statistics taken at the cosmic ray facility, equipped with 3 ATLAS BOS MDT chambers, in Garching (Munich) have been used to study temperature and pressure effects on gas gain and drifttime. The deformation of a thermally expanded chamber was reconstructed using the internal RasNik alignment monitoring system and the tracks from cosmic data. For these studies a heating system was designed to increase the temperature of the middle chamber by up to 20 Kelvins over room temperature. For comparison the temperature effects on gas properties have been simulated with Garfield. The maximum drifttime decreased under temperature raise by -2.21 +- 0.08 ns/K, in agreement with the results of pressure variations and the Garfield simulation. The increased temperatures led to a linear increase of the gas gain of about 2.1% 1/K. The chamber deformation has been analyzed with the help of reconstructed tracks. By the comparison of the tracks through the reference chambers with these through the test chamber the thermal expansion has been reconstructed and the result shows agreement with the theoretical expansion coefficient. As the wires are fixed at the end of the chamber, the wire position calculation can not provide a conclusion for the chamber middle. The complete deformation has been identified with the analysis of the monitoring system RasNik, whose measured values have shown a homogeneous expansion of the whole chamber, overlayed by a shift and a rotation of the chamber middle with respect to the outer part of the chamber. The established results of both methods are in agreement. We present as well a model for the position-drifttime correction as function of temperature.

  12. Chamber transport

    SciTech Connect (OSTI)

    OLSON,CRAIG L.

    2000-05-17T23:59:59.000Z

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  13. Passivity Based Adaptive Control of a Two Chamber Single Rod Hydraulic Actuator

    E-Print Network [OSTI]

    Li, Perry Y.

    Passivity Based Adaptive Control of a Two Chamber Single Rod Hydraulic Actuator Meng Wang and Perry based backstepping controller using a physical compressibility energy function for a chamber hydraulic produces an accurate trajectory tracking performance. I. INTRODUCTION Electronically controlled hydraulic

  14. Commissioning of SLAC SLD 45-Degree Chambers

    E-Print Network [OSTI]

    V. O. Eschenburg

    2002-07-30T23:59:59.000Z

    The SLD experiment at the Stanford Linear Accelerator Center had a significant gap in its muon tracking coverage, provided by the Warm Iron Calorimeter. Supplemental planes of limited streamer tube chambers were added to improve the coverage in the vicinity of the gap at 0.65 commissioning of the forty-five degree chamber region of the SLAC SLD Warm Iron Calorimeter is presented. This task involved the completion of the forty-five degree chamber region geometry for the Warm Iron Calorimeter's fitter and swimmer and the changing of the way multiple scattering effects are treated in the fitter algorithm.

  15. Radio Bubbles in Clusters

    E-Print Network [OSTI]

    R. J. H. Dunn; A. C. Fabian; G. B. Taylor

    2005-10-06T23:59:59.000Z

    We extend our earlier work on cluster cores with distinct radio bubbles, adding more active bubbles, i.e. those with Ghz radio emission, to our sample, and also investigating ``ghost bubbles,'' i.e. those without GHz radio emission. We have determined k, which is the ratio of the total particle energy to that of the electrons radiating between 10 MHz and 10 GHz. Constraints on the ages of the active bubbles confirm that the ratio of the energy factor, k, to the volume filling factor, f lies within the range 1 < k/f < 1000. In the assumption that there is pressure equilibrium between the radio-emitting plasma and the surrounding thermal X-ray gas, none of the radio lobes has equipartition between the relativistic particles and the magnetic field. A Monte-Carlo simulation of the data led to the conclusion that there are not enough bubbles present in the current sample to be able to determine the shape of the population. An analysis of the ghost bubbles in our sample showed that on the whole they have higher upper limits on k/f than the active bubbles, especially when compared to those in the same cluster. A study of the Brightest 55 cluster sample shows that 17, possibly 20, clusters required some form of heating as they have a short central cooling time, t_cool < 3 Gyr, and a large central temperature drop, T_centre/T_outer< 1/2. Of these between 12 (70 per cent) and 15 (75 per cent), contain bubbles. This indicates that the duty cycle of bubbles is large in such clusters and that they can play a major role in the heating process.

  16. Rotating bubble membrane radiator

    DOE Patents [OSTI]

    Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

    1988-12-06T23:59:59.000Z

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  17. Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your Home and It'll Love You Back Love Your PrincipalLiquids

  18. Donald Glaser, the Bubble Chamber, and Elementary Particles

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEA : Papers69 Federal

  19. The formation of gas bubbles at submerged orifices

    E-Print Network [OSTI]

    Hayes, William Bell

    1958-01-01T23:59:59.000Z

    . For values of Nc greater than 0.85, the formation and release of the bubbles appeared to occur almost simul? taneously. For the formation of bubbles at zero chamber volume and at low flow rates, the following equation was developed. (2) Ve * equilibrium... experimentally. The d determined for water (

  20. Bubble Radiation Detection: Current and Future Capability

    SciTech Connect (OSTI)

    AJ Peurrung; RA Craig

    1999-11-15T23:59:59.000Z

    Despite a number of noteworthy achievements in other fields, superheated droplet detectors (SDDs) and bubble chambers (BCs) have not been used for nuclear nonproliferation and arms control. This report examines these two radiation-detection technologies in detail and answers the question of how they can be or should be ''adapted'' for use in national security applications. These technologies involve closely related approaches to radiation detection in which an energetic charged particle deposits sufficient energy to initiate the process of bubble nucleation in a superheated fluid. These detectors offer complete gamma-ray insensitivity when used to detect neutrons. They also provide controllable neutron-energy thresholds and excellent position resolution. SDDs are extraordinarily simple and inexpensive. BCs offer the promise of very high efficiency ({approximately}75%). A notable drawback for both technologies is temperature sensitivity. As a result of this problem, the temperature must be controlled whenever high accuracy is required, or harsh environmental conditions are encountered. The primary findings of this work are listed and briefly summarized below: (1) SDDs are ready to function as electronics-free neutron detectors on demand for arms-control applications. The elimination of electronics at the weapon's location greatly eases the negotiability of radiation-detection technologies in general. (2) As a result of their high efficiency and sharp energy threshold, current BCs are almost ready for use in the development of a next-generation active assay system. Development of an instrument based on appropriately safe materials is warranted. (3) Both kinds of bubble detectors are ready for use whenever very high gamma-ray fields must be confronted. Spent fuel MPC and A is a good example where this need presents itself. (4) Both kinds of bubble detectors have the potential to function as low-cost replacements for conventional neutron detectors such as {sup 3}He tubes. For SDDs, this requires finding some way to get boron into the detector. For BCs, this requires finding operating conditions permitting a high duty cycle.

  1. The Formation of a Bubble from a Submerged Orifice

    E-Print Network [OSTI]

    Simmons, Jonathan A; Shikhmurzaev, Yulii D

    2015-01-01T23:59:59.000Z

    The formation of a single bubble from an orifice in a solid surface, submerged in an in- compressible, viscous Newtonian liquid, is simulated. The finite element method is used to capture the multiscale physics associated with the problem and to track the evolution of the free surface explicitly. The results are compared to a recent experimental analysis and then used to obtain the global characteristics of the process, the formation time and volume of the bubble, for a range of orifice radii; Ohnesorge numbers, which combine the material parameters of the liquid; and volumetric gas flow rates. These benchmark calculations, for the parameter space of interest, are then utilised to validate a selection of scaling laws found in the literature for two regimes of bubble formation, the regimes of low and high gas flow rates.

  2. Laser calibration system for the CERES Time Projection Chamber

    E-Print Network [OSTI]

    Dariusz Miskowiec; Peter Braun-Munzinger

    2008-02-15T23:59:59.000Z

    A Nd:YAG laser was used to simulate charged particle tracks at known positions in the CERES Time Projection Chamber at the CERN SPS. The system was primarily developed to study the response of the readout electronics and to calibrate the electron drift velocity. Further applications were the determination of the gating grid transparency, the chamber position calibration, and long-term monitoring of drift properties of the gas in the detector.

  3. Helium bubble bursting in tungsten

    SciTech Connect (OSTI)

    Sefta, Faiza [University of California, Berkeley, California 94720 (United States); Juslin, Niklas [University of Tennessee, Knoxville, Tennessee 37996 (United States); Wirth, Brian D., E-mail: bdwirth@utk.edu [University of Tennessee, Oak Ridge National Laboratory, Knoxville, Tennessee 37996 (United States)

    2013-12-28T23:59:59.000Z

    Molecular dynamics simulations have been used to systematically study the pressure evolution and bursting behavior of sub-surface helium bubbles and the resulting tungsten surface morphology. This study specifically investigates how bubble shape and size, temperature, tungsten surface orientation, and ligament thickness above the bubble influence bubble stability and surface evolution. The tungsten surface is roughened by a combination of adatom “islands,” craters, and pinholes. The present study provides insight into the mechanisms and conditions leading to various tungsten topology changes, which we believe are the initial stages of surface evolution leading to the formation of nanoscale fuzz.

  4. Breaking down the bubbly | EMSL

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

    geometry and enhanced visibility, can incorporate fluorescence microscopy to study CO2 bubble formation with high-impact details, such as showing exsolved CO2 gas mobility...

  5. BNL | ATF Experimental Chambers

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

    Laser Injection Vacuum Chamber Located on beam line 1, the "Smith-Purcell box" has 140 liters of usable volume. Due to its size, it is mounted on a fixed platform. Hosted...

  6. BNL | ATF Interaction Chambers

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

    chamber can be used for more than just plasma wakefield experiments. Dedicated 500 ls turbo pump and one auxiliary 200 ls turbo pump port. Normally operates in the 10-8 Torr...

  7. BNL | ATF Interaction Chambers

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

    with translation actuators. Beam profile monitors at interaction region as well as chamber entrance and exit. Available port for 200 ls turbo pump. Operates in the 10-8 Torr range...

  8. BNL | ATF Experimental Chambers

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

    entrance and exit. Dedicated ion pumps (250 ls total) with a port for one 200 ls turbo pump. Operates in the 10-8 Torr range. Photo of open DWFA chamber, in-situ on beam...

  9. Bubble masks for time-encoded imaging of fast neutrons.

    SciTech Connect (OSTI)

    Brubaker, Erik; Brennan, James S.; Marleau, Peter; Nowack, Aaron B.; Steele, John; Sweany, Melinda; Throckmorton, Daniel J.

    2013-09-01T23:59:59.000Z

    Time-encoded imaging is an approach to directional radiation detection that is being developed at SNL with a focus on fast neutron directional detection. In this technique, a time modulation of a detected neutron signal is induced-typically, a moving mask that attenuates neutrons with a time structure that depends on the source position. An important challenge in time-encoded imaging is to develop high-resolution two-dimensional imaging capabilities; building a mechanically moving high-resolution mask presents challenges both theoretical and technical. We have investigated an alternative to mechanical masks that replaces the solid mask with a liquid such as mineral oil. Instead of fixed blocks of solid material that move in pre-defined patterns, the oil is contained in tubing structures, and carefully introduced air gaps-bubbles-propagate through the tubing, generating moving patterns of oil mask elements and air apertures. Compared to current moving-mask techniques, the bubble mask is simple, since mechanical motion is replaced by gravity-driven bubble propagation; it is flexible, since arbitrary bubble patterns can be generated by a software-controlled valve actuator; and it is potentially high performance, since the tubing and bubble size can be tuned for high-resolution imaging requirements. We have built and tested various single-tube mask elements, and will present results on bubble introduction and propagation as a function of tubing size and cross-sectional shape; real-time bubble position tracking; neutron source imaging tests; and reconstruction techniques demonstrated on simple test data as well as a simulated full detector system.

  10. Microfluidic Actuation Using Electrochemically Generated Bubbles

    E-Print Network [OSTI]

    Sachs, Frederick

    Microfluidic Actuation Using Electrochemically Generated Bubbles Susan Z. Hua,*, Frederick Sachs, Buffalo, New York 14260 Bubble-based actuation in microfluidic applications is attractive owing closing) rate increases with applied voltage, small microfluidic dimensions accelerate bubble deflation

  11. Sleeve reaction chamber system

    DOE Patents [OSTI]

    Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

    2009-08-25T23:59:59.000Z

    A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

  12. A prediction for bubbling geometries

    E-Print Network [OSTI]

    Takuya Okuda

    2008-02-11T23:59:59.000Z

    We study the supersymmetric circular Wilson loops in N=4 Yang-Mills theory. Their vacuum expectation values are computed in the parameter region that admits smooth bubbling geometry duals. The results are a prediction for the supergravity action evaluated on the bubbling geometries for Wilson loops.

  13. Automated soil gas monitoring chamber

    DOE Patents [OSTI]

    Edwards, Nelson T.; Riggs, Jeffery S.

    2003-07-29T23:59:59.000Z

    A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within the chamber has been invented. The chamber opens between measurements and therefore does not alter the metabolic processes that influence soil gas efflux rates. A multiple chamber system provides for repetitive multi-point sampling, undisturbed metabolic soil processes between sampling, and an essentially airtight sampling chamber operating at ambient pressure.

  14. Cosmic Ray Test of Mini-drift Thick Gas Electron Multiplier Chamber for Transition Radiation Detector

    E-Print Network [OSTI]

    S. Yang; S. Das; B. Buck; C. Li; T. Ljubicic; R. Majka; M. Shao; N. Smirnov; G. Visser; Z. Xu; Y. Zhou

    2015-02-17T23:59:59.000Z

    A thick gas electron multiplier (THGEM) chamber with an effective readout area of 10$\\times$10 cm$^{2}$ and a 11.3 mm ionization gap has been tested along with two regular gas electron multiplier (GEM) chambers in a cosmic ray test system. The thick ionization gap makes the THGEM chamber a mini-drift chamber. This kind mini-drift THGEM chamber is proposed as part of a transition radiation detector (TRD) for identifying electrons at an Electron Ion Collider (EIC) experiment. Through this cosmic ray test, an efficiency larger than 94$\\%$ and a spatial resolution $\\sim$220 $\\mu$m are achieved for the THGEM chamber at -3.65 kV. Thanks to its outstanding spatial resolution and thick ionization gap, the THGEM chamber shows excellent track reconstruction capability. The gain uniformity and stability of the THGEM chamber are also presented.

  15. Bubble column apparatus for separating wax from catalyst slurry

    DOE Patents [OSTI]

    Neathery, James K.; Davis, Burtron H.

    2004-07-13T23:59:59.000Z

    Novel methods and devices for production of liquid hydrocarbon products from gaseous reactants are disclosed. In one aspect, a method for separating a liquid hydrocarbon, typically a wax, from a catalyst containing slurry is provided, comprising passing the slurry through at least one downcomer extending from an overhead separation chamber and discharging into the bottom of a slurry bubble column reactor. The downcomer includes a cross-flow filtration element for separating a substantially particle-free liquid hydrocarbon for downstream processing. In another aspect, a method for promoting plug-flow movement in a recirculating slurry bubble column reactor is provided, comprising discharging the recirculating slurry into the reactor through at least one downcomer which terminates near the bottom of the reactor. Devices for accomplishing the above methods are also provided.

  16. Anatomy of bubbling solutions

    E-Print Network [OSTI]

    Kostas Skenderis; Marika Taylor

    2008-05-23T23:59:59.000Z

    We present a comprehensive analysis of holography for the bubbling solutions of Lin-Lunin-Maldacena. These solutions are uniquely determined by a coloring of a 2-plane, which was argued to correspond to the phase space of free fermions. We show that in general this phase space distribution does not determine fully the 1/2 BPS state of N=4 SYM that the gravitational solution is dual to, but it does determine it enough so that vevs of all single trace 1/2 BPS operators in that state are uniquely determined to leading order in the large N limit. These are precisely the vevs encoded in the asymptotics of the LLM solutions. We extract these vevs for operators up to dimension 4 using holographic renormalization and KK holography and show exact agreement with the field theory expressions.

  17. Liquid Wall Chambers

    SciTech Connect (OSTI)

    Meier, W R

    2011-02-24T23:59:59.000Z

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  18. Secondary emission gas chamber

    E-Print Network [OSTI]

    V. In'shakov; V. Kryshkin; V. Skvortsov

    2014-12-10T23:59:59.000Z

    For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

  19. The Monitored Drift Tube Chambers of Atlas

    SciTech Connect (OSTI)

    Ventura, S. [INFN - Laboratori Nazionali di Frascati (Italy)

    2005-10-12T23:59:59.000Z

    The Atlas experiment has been designed to explore the high energy physics frontier at the TeV energy scale and to investigate on the physics of the Standard Model and beyond at the Large Hadron Collider (LHC) at Cern. The Muon Spectrometer represents the most part of the Atlas detector. It has been designed to provide standalone measurement of the transverse muon momenta with a relative accuracy of 3% over a wide momentum range up to 10% for momenta of 1 TeV. This high accuracy is provided by the Monitored Drift-Tube chambers (MDT) which can determine the track trajectory with a precision of 40 {mu}m.

  20. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

    1989-06-27T23:59:59.000Z

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  1. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

    1989-10-17T23:59:59.000Z

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  2. Bubble nucleation in stout beers

    E-Print Network [OSTI]

    Lee, W T; Devereux, M

    2011-01-01T23:59:59.000Z

    Bubble nucleation in weakly supersaturated solutions of carbon dioxide - such as champagne, sparkling wines and carbonated beers - is well understood. Bubbles grow and detach from nucleation sites: gas pockets trapped within hollow cellulose fibres. This mechanism appears not to be active in stout beers that are supersaturated solutions of nitrogen and carbon dioxide. In their canned forms these beers require additional technology (widgets) to release the bubbles which will form the head of the beer. We extend the mathematical model of bubble nucleation in carbonated liquids to the case of two gasses and show that this nucleation mechanism is active in stout beers, though substantially slower than in carbonated beers and confirm this by observation. A rough calculation suggests that despite the slowness of the process, applying a coating of hollow porous fibres to the inside of a can or bottle could be a potential replacement for widgets.

  3. Three chamber negative ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA); Hiskes, John R. (Livermore, CA)

    1985-01-01T23:59:59.000Z

    A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

  4. Chamber for the optical manipulation of microscopic particles

    DOE Patents [OSTI]

    Buican, Tudor N. (Los Alamos, NM); Upham, Bryan D. (Los Alamos, NM)

    1992-01-01T23:59:59.000Z

    A particle control chamber enables experiments to be carried out on biological cells and the like using a laser system to trap and manipulate the particles. A manipulation chamber provides a plurality of inlet and outlet ports for the particles and for fluids used to control or to contact the particles. A central manipulation area is optically accessible by the laser and includes first enlarged volumes for containing a selected number of particles for experimentation. A number of first enlarged volumes are connected by flow channels through second enlarged volumes. The second enlarged volumes act as bubble valves for controlling the interconnections between the first enlarged volumes. Electrode surfaces may be applied above the first enlarged volumes to enable experimentation using the application of electric fields within the first enlarged volumes. A variety of chemical and environmental conditions may be established within individual first enlarged volumes to enable experimental conditions for small scale cellular interactions.

  5. TRACKING SITE

    Energy Science and Technology Software Center (OSTI)

    003235MLTPL00 AASG Geothermal Data submissions tracking application and site.  https://github.com/usgin/aasgtrack 

  6. Ionization chamber dosimeter

    DOE Patents [OSTI]

    Renner, Tim R. (Berkeley, CA); Nyman, Mark A. (Berkeley, CA); Stradtner, Ronald (Kensington, CA)

    1991-01-01T23:59:59.000Z

    A method for fabricating an ion chamber dosimeter collecting array of the type utilizing plural discrete elements formed on a uniform collecting surface which includes forming a thin insulating layer over an aperture in a frame having surfaces, forming a predetermined pattern of through holes in the layer, plating both surfaces of the layer and simultaneously tilting and rotating the frame for uniform plate-through of the holes between surfaces. Aligned masking and patterned etching of the surfaces provides interconnects between the through holes and copper leads provided to external circuitry.

  7. Fig. 1. On the right is the Cloud Chamber, on the left is a laptop running the Cloud Catcher software ( Alexis Kirke.)

    E-Print Network [OSTI]

    Miranda, Eduardo Reck

    in real time. A glass cloud chamber was used onstage to make radioactivity visible in bright white tracksFig. 1. On the right is the Cloud Chamber, on the left is a laptop running the Cloud Catcher software (© Alexis Kirke.) CLOUD CHAMBER: A PERFORMANCE WITH REAL TIME TWO-WAY INTERACTION BETWEEN

  8. Bubble formation in Rangely Field, Colorado

    E-Print Network [OSTI]

    Wood, J. W

    1953-01-01T23:59:59.000Z

    tc Determine the Effect of Times Of. Standing on Time &equired for Bubble Formation at 67 psi Supersaturaticns. Page 20 Tests to Determine Bubble Frequency. Average Bubble Frequency Data. 23 27 The data reported in this thesis deal... if present, or would tend to form one. However, as the pressure on the saturated oil declines, the oil becomes supersatur- ated, except as bubbles may form and diffusion take place tc eliminate the supersaturation. This research is devoted to a study...

  9. Expansion of Bubbles in Inflationary Universe

    E-Print Network [OSTI]

    M. Mohazzab; M. M. Sheikh Jabbari; H. Salehi

    1995-10-14T23:59:59.000Z

    We show that particle production during the expansion of bubbles of true vacuum in the sea of false vacuum is possible and calculate the resulting rate. As a result the nucleated bubbles cannot expand due to the transfer of false vacuum energy to the created particles inside the bubbles. Therefore all the inflationary models dealing with the nucleation and expansion of the bubbles (including extended inflation) may not be viable.

  10. Active microuidic mixer and gas bubble lter driven by thermal bubble micropump$

    E-Print Network [OSTI]

    Lin, Liwei

    to be proportional to the one-third power of the input pulse frequency. Furthermore, a gas bubble ®lter is integratedActive micro¯uidic mixer and gas bubble ®lter driven by thermal bubble micropump$ Jr-Hung Tsaia Abstract A micro¯uidic mixer with a gas bubble ®lter activated by a thermal bubble actuated nozzle

  11. The Laser Calibration System of the ALICE Time Projection Chamber

    E-Print Network [OSTI]

    G. Renault; B. S. Nielsen; J. Westergaard; J. J. Gaardhøje

    2005-11-07T23:59:59.000Z

    A Large Ion Collider Experiment (ALICE) is the only experiment at the Large Hadron Collider (LHC) dedicated to the study of heavy ion collisions. The Time Projection Chamber (TPC) is the main tracking detector covering the pseudo rapidity range $|\\eta|laser system is to simulate ionizing tracks at predifined positions throughout the drift volume in order to monitor the TPC response to a known source. In particular, the alignment of the read-out chambers will be performed, and variations of the drift velocity due to drift field imperfections can be measured and used as calibration data in the physics data analysis. In this paper we present the design of the pulsed UV laser and optical system, together with the control and monitoring systems.

  12. Tiny Bubbles in my BEC

    SciTech Connect (OSTI)

    Blinova, Alina A. [Los Alamos National Laboratory

    2012-08-01T23:59:59.000Z

    Ultracold atomic gases provide a unique way for exploring many-body quantum phenomena that are inaccessible to conventional low-temperature experiments. Nearly two decades ago the Bose-Einstein condensate (BEC) - an ultracold gas of bosons in which almost all bosons occupy the same single-particle state - became experimentally feasible. Because a BEC exhibits superfluid properties, it can provide insights into the behavior of low-temperature helium liquids. We describe the case of a single distinguishable atom (an impurity) embedded in a BEC and strongly coupled to the BEC bosons. Depending on the strength of impurity-boson and boson-boson interactions, the impurity self-localizes into two fundamentally distinct regimes. The impurity atom can behave as a tightly localized 'polaron,' akin to an electron in a dielectric crystal, or as a 'bubble,' an analog to an electron bubble in superfluid helium. We obtain the ground state wavefunctions of the impurity and BEC by numerically solving the two coupled Gross-Pitaevskii equations that characterize the system. We employ the methods of imaginary time propagation and conjugate gradient descent. By appropriately varying the impurity-boson and boson-boson interaction strengths, we focus on the polaron to bubble crossover. Our results confirm analytical predictions for the polaron limit and uncover properties of the bubble regime. With these results we characterize the polaron to bubble crossover. We also summarize our findings in a phase diagram of the BEC-impurity system, which can be used as a guide in future experiments.

  13. Readout of TPC Tracking Chambers with GEMs and Pixel Chip

    E-Print Network [OSTI]

    Kim, T.

    2008-01-01T23:59:59.000Z

    insulating spacers are of Lucite or G10. Dimensions are inspacers. This package was mounted inside a cylindrical stainless steel test vessel (TV) with approximate inside dimensions

  14. Ion chamber based neutron detectors

    DOE Patents [OSTI]

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16T23:59:59.000Z

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  15. Bubbling the False Vacuum Away

    E-Print Network [OSTI]

    Marcelo Gleiser; Barrett Rogers; Joel Thorarinson

    2007-08-28T23:59:59.000Z

    We investigate the role of nonperturbative, bubble-like inhomogeneities on the decay rate of false-vacuum states in two and three-dimensional scalar field theories. The inhomogeneities are induced by setting up large-amplitude oscillations of the field about the false vacuum as, for example, after a rapid quench or in certain models of cosmological inflation. We show that, for a wide range of parameters, the presence of large-amplitude bubble-like inhomogeneities greatly accelerates the decay rate, changing it from the well-known exponential suppression of homogeneous nucleation to a power-law suppression. It is argued that this fast, power-law vacuum decay -- known as resonant nucleation -- is promoted by the presence of long-lived oscillons among the nonperturbative fluctuations about the false vacuum. A phase diagram is obtained distinguishing three possible mechanisms for vacuum decay: homogeneous nucleation, resonant nucleation, and cross-over. Possible applications are briefly discussed.

  16. DNA Bubble Life Time in Denaturation

    E-Print Network [OSTI]

    Zh. S. Gevorkian; Chin-Kun Hu

    2010-10-11T23:59:59.000Z

    We have investigated the denaturation bubble life time for a homogeneous as well as for a heterogeneous DNA within a Poland-Scheraga model. It is shown that at criticality the bubble life time for a homogeneous DNA is finite provided that the loop entropic exponent c>2 and has a scaling dependence on DNA length for c<2. Heterogeneity in the thermodynamical limit makes the bubble life time infinite for any entropic exponent.

  17. Collapse of vacuum bubbles in a vacuum

    SciTech Connect (OSTI)

    Ng, Kin-Wang; Wang, Shang-Yung [Institute of Physics, Academia Sinica, Taipei, Taiwan 11529 (China); Department of Physics, Tamkang University, Tamsui, Taiwan 25137 (China)

    2011-02-15T23:59:59.000Z

    We revisit the dynamics of a false vacuum bubble in a background de Sitter spacetime. We find that there exists a large parameter space that allows the bubble to collapse into a black hole or to form a wormhole. This may have interesting implications for the creation of a baby universe in the laboratory, the string landscape where the bubble nucleation takes place among a plenitude of metastable vacua, and the inflationary physics.

  18. The impact of bubble diffusivity on confined oscillated bubbly liquid Sergey Shklyaev1

    E-Print Network [OSTI]

    Straube, Arthur V.

    their volume. In other words, in a liquid containing bubbles the speed of sound cb can b oscillations4,5 to the frequency of external driving. Here, k= /c0 is the wave number, c0 is the speed of soundThe impact of bubble diffusivity on confined oscillated bubbly liquid Sergey Shklyaev1 and Arthur V

  19. The incorporation of bubbles into a computer graphics fluid simulation

    E-Print Network [OSTI]

    Greenwood, Shannon Thomas

    2005-08-29T23:59:59.000Z

    We present methods for incorporating bubbles into a photorealistc fluid simulation. Previous methods of fluid simulation in computer graphics do not include bubbles. Our system automatically creates bubbles, which are simulated on top of the fluid...

  20. Visualizing Buoyant Burning Bubbles in Type Ia Supernovae at...

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

    Burning in Supernovae Buoyant Burning Bubbles in Type Ia Supernovae bubble-s.jpeg Flame ignition in type Ia supernovae leads to isolated bubbles of burning buoyant fluid. As a...

  1. Hydrogen Bubbles and Formation of Nanoporous Silicon during Electroche...

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

    Bubbles and Formation of Nanoporous Silicon during Electrochemical Etching. Hydrogen Bubbles and Formation of Nanoporous Silicon during Electrochemical Etching. Abstract: Many...

  2. Effects of interfacial surfactant contamination on bubble gas transfer

    E-Print Network [OSTI]

    Rosso, D; Huo, D L; Stenstrom, M K

    2006-01-01T23:59:59.000Z

    inside gas bubbles. Chemical Engineering Science 3, 1–11.D. Rosso et al. / Chemical Engineering Science 61 (2006)cap bubbles. Chemical Engineering Science 30, 1507–1510.

  3. Bubbling Reactor Technology for Rapid Synthesis of Uniform, Small...

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

    Bubbling Reactor Technology for Rapid Synthesis of Uniform, Small MFI-Type Zeolite Crystals . Bubbling Reactor Technology for Rapid Synthesis of Uniform, Small MFI-Type Zeolite...

  4. Oscillating plasma bubbles. II. Pulsed experiments

    SciTech Connect (OSTI)

    Stenzel, R. L.; Urrutia, J. M. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)

    2012-08-15T23:59:59.000Z

    Time-dependent phenomena have been investigated in plasma bubbles which are created by inserting spherical grids into an ambient plasma and letting electrons and ions form a plasma of different parameters than the ambient one. There are no plasma sources inside the bubble. The grid bias controls the particle flux. There are sheaths on both sides of the grid, each of which passes particle flows in both directions. The inner sheath or plasma potential develops self consistently to establish charge neutrality and divergence free charge and mass flows. When the electron supply is restricted, the inner sheath exhibits oscillations near the ion plasma frequency. When all electrons are excluded, a virtual anode forms on the inside sheath, reflects all ions such that the bubble is empty. By pulsing the ambient plasma, the lifetime of the bubble plasma has been measured. In an afterglow, plasma electrons are trapped inside the bubble and the bubble decays as slow as the ambient plasma. Pulsing the grid voltage yields the time scale for filling and emptying the bubble. Probes have been shown to modify the plasma potential. Using pulsed probes, transient ringing on the time scale of ion transit times through the bubble has been observed. The start of sheath oscillations has been investigated. The instability mechanism has been qualitatively explained. The dependence of the oscillation frequency on electrons in the sheath has been clarified.

  5. Towards observable signatures of other bubble universes

    SciTech Connect (OSTI)

    Aguirre, Anthony; Johnson, Matthew C.; Shomer, Assaf [SCIPP, University of California, Santa Cruz, California 95064 (United States)

    2007-09-15T23:59:59.000Z

    We evaluate the possibility of observable effects arising from collisions between vacuum bubbles in a universe undergoing false-vacuum eternal inflation. Contrary to conventional wisdom, we find that under certain assumptions most positions inside a bubble should have access to a large number of collision events. We calculate the expected number and angular size distribution of such collisions on an observer's 'sky', finding that for typical observers the distribution is anisotropic and includes many bubbles, each of which will affect the majority of the observer's sky. After a qualitative discussion of the physics involved in collisions between arbitrary bubbles, we evaluate the implications of our results, and outline possible detectable effects. In an optimistic sense, then, the present paper constitutes a first step in an assessment of the possible effects of other bubble universes on the cosmic microwave background and other observables.

  6. Solar prominences: 'double, double ... boil and bubble'

    E-Print Network [OSTI]

    Keppens, Rony

    2015-01-01T23:59:59.000Z

    Observations revealed rich dynamics within prominences, the cool 10,000 K, macroscopic (sizes of order 100 Mm) "clouds" in the million degree solar corona. Even quiescent prominences are continuously perturbed by hot, rising bubbles. Since prominence matter is hundredfold denser than coronal plasma, this bubbling is related to Rayleigh-Taylor instabilities. Here we report on true macroscopic simulations well into this bubbling phase, adopting a magnetohydrodynamic description from chromospheric layers up to 30 Mm height. Our virtual prominences rapidly establish fully non-linear (magneto)convective motions where hot bubbles interplay with falling pillars, with dynamical details including upwelling pillars forming within bubbles. Our simulations show impacting Rayleigh-Taylor fingers reflecting on transition region plasma, ensuring that cool, dense chromospheric material gets mixed with prominence matter up to very large heights. This offers an explanation for the return mass cycle mystery for prominence mater...

  7. Gas bubble dynamics in soft materials

    E-Print Network [OSTI]

    J. M. Solano-Altamirano; John D. Malcolm; Saul Goldman

    2014-10-14T23:59:59.000Z

    Epstein and Plesset's seminal work on the rate of gas bubble dissolution and growth in a simple liquid is generalized to render it applicable to a gas bubble embedded in a soft elastic medium. Both the underlying diffusion equation and the expression for the gas bubble pressure were modified to allow for the non-zero shear modulus of the elastic medium. The extension of the diffusion equation results in a trivial shift (by an additive constant) in the value of the diffusion coefficient, and does not change the form of the rate equations. But the use of a Generalized Young-Laplace equation for the bubble pressure resulted in significant differences on the dynamics of bubble dissolution and growth, relative to a simple liquid medium. Depending on whether the salient parameters (solute concentration, initial bubble radius, surface tension, and shear modulus) lead to bubble growth or dissolution, the effect of allowing for a non-zero shear modulus in the Generalized Young-Laplace equation is to speed up the rate of bubble growth, or to reduce the rate of bubble dissolution, respectively. The relation to previous work on visco-elastic materials is discussed, as is the connection of this work to the problem of Decompression Sickness (specifically, "the bends"). Examples of tissues to which our expressions can be applied are provided. Also, a new phenomenon is predicted whereby, for some parameter values, a bubble can be metastable and persist for long times, or it may grow, when embedded in a homogeneous under-saturated soft elastic medium.

  8. Assessment of the high temperature fission chamber technology for the French fast reactor program

    SciTech Connect (OSTI)

    Jammes, C.; Filliatre, P.; Geslot, B.; Domenech, T.; Normand, S. [Commissariat a l'Energie Atomique, CEA (France)

    2011-07-01T23:59:59.000Z

    High temperature fission chambers are key instruments for the control and protection of the sodium-cooled fast reactor. First, the developments of those neutron detectors, which are carried out either in France or abroad are reviewed. Second, the French realizations are assessed with the use of the technology readiness levels in order to identify tracks of improvement. (authors)

  9. VERTEX CHAMBERS TARGET CELL CALORIMETER

    E-Print Network [OSTI]

    DRIFT VC 1/2 FC 1/2 VERTEX CHAMBERS TARGET CELL DVC MC 1­3 HODOSCOPE H0 MONITOR BC 1/2 BC 3/4 TRD at Threashold Lambda Physics (u ­L spin transfer) Motivation: ­ W L Target cell e beam L p p e ­ Elastic: Peltier elements ( T ~ ­20C ) ­ Custom built electronics + HELIX chips low autgassing (

  10. Microfluidics Formation of Bubbles in a Multisection Flow-Focusing

    E-Print Network [OSTI]

    Prentiss, Mara

    Microfluidics Formation of Bubbles in a Multisection Flow-Focusing Junction Michinao Hashimoto the stable formation of trains of mono-, bi-, and tri-disperse bubbles in microfluidic flow- focusing (FF-assembly through the patterns of flow created by the bubbles. 1.1 Bubbles and Droplets in Microfluidics

  11. Engineering development of a bubble tray structure 

    E-Print Network [OSTI]

    Glitsch, Hans C

    1954-01-01T23:59:59.000Z

    pass thxough agitable openings 3. n the bubble trayS and be caused to bubble through the liquid cax'ried on the trays. This is usually Bccomp3. :lshed bv providing a sex ies of vapor chimneys on each bu'bble tray, with each vapor chimney being... esistant covex- ing could be formed to fit the carbon steel stxuctural shape, and attached to the carbon steel structural shape by suitable means such as arc ox spot welding. Structural channel shapes were considex'ed as they cou'id be assembled...

  12. -The Bubble Chamber -http://thebubblechamber.org -Review: Cold War Social Science

    E-Print Network [OSTI]

    Solovey, Mark

    War institutions such as the RAND corporation, along with technological changes and the perceived developmental psychologist John Bowlby: "Whenever I hear the issue of maternal deprivation being discussed, I, for the obvious reason that they need their women at work and thus their children must be cared for by others

  13. Cycle Track Lessons Learned

    E-Print Network [OSTI]

    Bertini, Robert L.

    Cycle Track Lessons Learned #12;Presentation Overview · Bicycling trends · Cycle track lessons learned · What is a "Cycle track"? · Essential design elements of cycle tracks Separation Width Crossing

  14. Wetting of soap bubbles on hydrophilic, hydrophobic and superhydrophobic surfaces

    E-Print Network [OSTI]

    Steve Arscott

    2013-03-26T23:59:59.000Z

    Wetting of sessile bubbles on solid and liquid surfaces has been studied. A model is presented for the contact angle of a sessile bubble based on a modified Young equation - the experimental results agree with the model. A hydrophilic surface results in a bubble contact angle of 90 deg whereas on a superhydrophobic surface one observes 134 deg. For hydrophilic surfaces, the bubble angle diminishes with bubble radius - whereas on a superhydrophobic surface, the bubble angle increases. The size of the Plateau borders governs the bubble contact angle - depending on the wetting of the surface.

  15. Wetting of soap bubbles on hydrophilic, hydrophobic and superhydrophobic surfaces

    E-Print Network [OSTI]

    Arscott, Steve

    2013-01-01T23:59:59.000Z

    Wetting of sessile bubbles on solid and liquid surfaces has been studied. A model is presented for the contact angle of a sessile bubble based on a modified Young equation - the experimental results agree with the model. A hydrophilic surface results in a bubble contact angle of 90 deg whereas on a superhydrophobic surface one observes 134 deg. For hydrophilic surfaces, the bubble angle diminishes with bubble radius - whereas on a superhydrophobic surface, the bubble angle increases. The size of the Plateau borders governs the bubble contact angle - depending on the wetting of the surface.

  16. Chamber dynamic research with pulsed power

    SciTech Connect (OSTI)

    PETERSON,ROBERT R.; OLSON,CRAIG L.; RENK,TIMOTHY J.; ROCHAU,GARY E.; SWEENEY,MARY ANN

    2000-05-15T23:59:59.000Z

    In Inertial Fusion Energy (IFE), Target Chamber Dynamics (TCD) is an integral part of the target chamber design and performance. TCD includes target output deposition of target x-rays, ions and neutrons in target chamber gases and structures, vaporization and melting of target chamber materials, radiation-hydrodynamics in target chamber vapors and gases, and chamber conditions at the time of target and beam injections. Pulsed power provides a unique environment for IFE-TCD validation experiments in two important ways: they do not require the very clean conditions which lasers need and they currently provide large x-ray and ion energies.

  17. Nucleate boiling bubble growth and departure

    E-Print Network [OSTI]

    Staniszewski, Bogumil E.

    1959-01-01T23:59:59.000Z

    The vapor bubble formation on the heating surface during pool boiling has been studied experimentally. Experiments were made at the atmospheric pressure 28 psi and 40 psi, using degassed distilled water and ethanol. The ...

  18. Math of Popping Bubbles in a Foam

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

    within the bubble membranes, which can create rainbow hues like an oil slick on wet pavement. Then they used NERSC's Hopper Systems to solve the full set of equations of motion....

  19. Bubble collisions and measures of the multiverse

    E-Print Network [OSTI]

    Michael P. Salem

    2011-12-13T23:59:59.000Z

    To compute the spectrum of bubble collisions seen by an observer in an eternally-inflating multiverse, one must choose a measure over the diverging spacetime volume, including choosing an "initial" hypersurface below which there are no bubble nucleations. Previous calculations focused on the case where the initial hypersurface is pushed arbitrarily deep into the past. Interestingly, the observed spectrum depends on the orientation of the initial hypersurface, however one's ability observe the effect rapidly decreases with the ratio of inflationary Hubble rates inside and outside one's bubble. We investigate whether this conclusion might be avoided under more general circumstances, in particular placing the observer's bubble near the initial hypersurface. We find that it is not. As a point of reference, a substantial appendix reviews relevant aspects of the measure problem of eternal inflation.

  20. Bubble collisions and measures of the multiverse

    SciTech Connect (OSTI)

    Salem, Michael P., E-mail: salem@cosmos.phy.tufts.edu [Department of Physics, Stanford University, Stanford, CA 94305 (United States)

    2012-01-01T23:59:59.000Z

    To compute the spectrum of bubble collisions seen by an observer in an eternally-inflating multiverse, one must choose a measure over the diverging spacetime volume, including choosing an ''initial'' hypersurface below which there are no bubble nucleations. Previous calculations focused on the case where the initial hypersurface is pushed arbitrarily deep into the past. Interestingly, the observed spectrum depends on the orientation of the initial hypersurface, however one's ability observe the effect rapidly decreases with the ratio of inflationary Hubble rates inside and outside one's bubble. We investigate whether this conclusion might be avoided under more general circumstances, including placing the observer's bubble near the initial hypersurface. We find that it is not. As a point of reference, a substantial appendix reviews relevant aspects of the measure problem of eternal inflation.

  1. Universe out of a breathing bubble

    SciTech Connect (OSTI)

    Guendelman, Eduardo I.; Sakai, Nobuyuki [Physics Department, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel); Department of Education, Yamagata University, Yamagata 990-8560 (Japan)

    2008-06-15T23:59:59.000Z

    We consider the model of a false-vacuum bubble with a thin wall where the surface energy density is composed of two different components, 'domain-wall' type and 'dust' type, with opposite signs. We find stably oscillating solutions, which we call 'breathing bubbles'. By decay to a lower mass state, such a breathing bubble could become either (i) a child universe or ii) a bubble that 'eats up' the original universe, depending on the sign of the surface energy of the domain-wall component. We also discuss the effect of the finite-thickness corrections to the thin-wall approximation and possible origins of the energy contents of our model.

  2. Analytical Modeling of a Bubble Column Dehumidifier

    E-Print Network [OSTI]

    Tow, Emily W.

    Bubble column dehumidifiers are a compact, inexpensive alternative to conventional fin-tube dehumidifiers for humidification-dehumidification (HDH) desalination, a technology that has promising applications in small-scale ...

  3. Gravity waves from cosmic bubble collisions

    SciTech Connect (OSTI)

    Salem, Michael P.; Saraswat, Prashant; Shaghoulian, Edgar, E-mail: mpsalem@stanford.edu, E-mail: ps88@stanford.edu, E-mail: edgars@stanford.edu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, California 94305 (United States)

    2013-02-01T23:59:59.000Z

    Our local Hubble volume might be contained within a bubble that nucleated in a false vacuum with only two large spatial dimensions. We study bubble collisions in this scenario and find that they generate gravity waves, which are made possible in this context by the reduced symmetry of the global geometry. These gravity waves would produce B-mode polarization in the cosmic microwave background, which could in principle dominate over the inflationary background.

  4. Towards observable signatures of other bubble universes. II. Exact solutions for thin-wall bubble collisions

    SciTech Connect (OSTI)

    Aguirre, Anthony [SCIPP, University of California, Santa Cruz, CA 95064 (United States); Johnson, Matthew C. [California Institute of Technology, Pasadena, CA 91125 (United States)

    2008-06-15T23:59:59.000Z

    We assess the effects of a collision between two vacuum bubbles in the thin-wall limit. After describing the outcome of a generic collision possessing the expected hyperbolic symmetry, we focus on collisions experienced by a bubble containing positive vacuum energy, which could in principle contain our observable universe. We provide criteria governing whether the post-collision domain wall accelerates towards or away from this observation bubble, and discuss the implications for observers located at various positions inside of the bubble. Then, we identify the class of solutions which have minimal impact on the interior of the observation bubble, and derive a simple formula for the energy density of a shell of radiation emitted from such a collision. In the context of a universe undergoing false-vacuum eternal inflation, these solutions are perhaps the most promising candidates for collisions that could exist within our past light cone, and therefore in principle be observable.

  5. Construction and test of high precision drift-tube (sMDT) chambers for the ATLAS muon spectrometer

    E-Print Network [OSTI]

    Sebastian Nowak; Oliver Korner; Hubert Kroha; Philipp Schwegler; Federico Sforza

    2014-07-01T23:59:59.000Z

    For the upgrade of the ATLAS muon spectrometer in March 2014 new muon tracking chambers (sMDT) with drift-tubes of 15 mm diameter, half of the value of the standard ATLAS Monitored Drift-Tubes (MDT) chambers, and 10~$\\mu$m positioning accuracy of the sense wires have been constructed. The new chambers are designed to be fully compatible with the present ATLAS services but, with respect to the previously installed ATLAS MDT chambers, they are assembled in a more compact geometry and they deploy two additional tube layers that provide redundant rack information. The chambers are composed of 8 layers of in total 624 aluminium drift-tubes. The assembly of a chamber is completed within a week. A semi-automatized production line is used for the assembly of the drift-tubes prior to the chamber assembly. The production procedures and the quality control tests of the single components and of the complete chambers will be discussed. The wire position in the completed chambers have been measured by using a coordinate measuring machine.

  6. TRU waste characterization chamber gloveboxes.

    SciTech Connect (OSTI)

    Duncan, D. S.

    1998-07-02T23:59:59.000Z

    Argonne National Laboratory-West (ANL-W) is participating in the Department of Energy's (DOE) National Transuranic Waste Program in support of the Waste Isolation Pilot Plant (WIPP). The Laboratory's support currently consists of intrusive characterization of a selected population of drums containing transuranic waste. This characterization is performed in a complex of alpha containment gloveboxes termed the Waste Characterization Gloveboxes. Made up of the Waste Characterization Chamber, Sample Preparation Glovebox, and the Equipment Repair Glovebox, they were designed as a small production characterization facility for support of the Idaho National Engineering and Environmental Laboratory (INEEL). This paper presents salient features of these gloveboxes.

  7. Design and performance testing of the read-out boards for the CMS-DT chambers

    E-Print Network [OSTI]

    Fernández, C; Marin, J; Oller, J C; Willmott, C

    2002-01-01T23:59:59.000Z

    Read-out boards (ROB) are one of the key elements of readout system for CMS barrel muon drift chambers. To insure proper and reliable operation under all detector environmental conditions an exhaustive set of tests have been developed and performed on the 30 pre-series ROB's before production starts. These tests include operation under CMS radiation conditions to detect and estimate SEU rates, validation with real chamber signals and trigger rates, studies of time resolution and linearity, crosstalk analysis, track pattern generation for calibration and on-line tests, and temperature cycling to uncover marginal conditions. We present the status of the ROB and tests results. (5 refs).

  8. Final Independent External Peer Review Report Bubbly Creek Ecosystem Restoration

    E-Print Network [OSTI]

    US Army Corps of Engineers

    Final Independent External Peer Review Report Bubbly Creek Ecosystem Restoration Feasibility Study National Planning Center of Expertise for Ecosystem Restoration Mississippi Valley Division Contract No. W Report Bubbly Creek Ecosystem Restoration Feasibility Study Prepared by Battelle 505 King Avenue Columbus

  9. Multiverse rate equation including bubble collisions

    E-Print Network [OSTI]

    Michael P. Salem

    2013-02-19T23:59:59.000Z

    The volume fractions of vacua in an eternally inflating multiverse are described by a coarse-grain rate equation, which accounts for volume expansion and vacuum transitions via bubble formation. We generalize the rate equation to account for bubble collisions, including the possibility of classical transitions. Classical transitions can modify the details of the hierarchical structure among the volume fractions, with potential implications for the staggering and Boltzmann-brain issues. Whether or not our vacuum is likely to have been established by a classical transition depends on the detailed relationships among transition rates in the landscape.

  10. Bubble visualization in a simulated hydraulic jump

    E-Print Network [OSTI]

    Witt, Adam; Shen, Lian

    2013-01-01T23:59:59.000Z

    This is a fluid dynamics video of two- and three-dimensional computational fluid dynamics simulations carried out at St. Anthony Falls Laboratory. A transient hydraulic jump is simulated using OpenFOAM, an open source numerical solver. A Volume of Fluid numerical method is employed with a realizable k-epsilon turbulence model. The goal of this research is to model the void fraction and bubble size in a transient hydraulic jump. This fluid dynamics video depicts the air entrainment characteristics and bubble behavior within a hydraulic jump of Froude number 4.82.

  11. Analysis of Strategic Petroleum Reserve bubble point pressure data

    SciTech Connect (OSTI)

    Lott, S.E.

    1996-05-01T23:59:59.000Z

    Mathematical models are presented to predict the bubble pressure for 481 cavern oil samples withdrawn from the Bryan Mound, West Hackberry, Big Hill, and Bayou Choctaw Strategic Petroleum Reserve sites. The predicted bubble point pressure is compared to experimentally measured bubble point pressure to resolve potential sources of error introduced to the experimental analysis. In order to gain a higher level of confidence in the measurement of the bubble point pressure, a stochastic analysis of the data is recommended in the future.

  12. Electromechanical solar tracking apparatus

    DOE Patents [OSTI]

    Stromberg, Robert P. (Albuquerque, NM)

    1981-01-01T23:59:59.000Z

    The invention relates to an electromechanical solar tracking device which tracks the position of the sun using paired, partially-shaded bimetallic elements.

  13. Fluidized wall for protecting fusion chamber walls

    DOE Patents [OSTI]

    Maniscalco, James A. (Danville, CA); Meier, Wayne R. (Livermore, CA)

    1982-01-01T23:59:59.000Z

    Apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithium-ceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

  14. Learning Overcomplete Spatiotemporal Bubbles from Natural Image Sequences

    E-Print Network [OSTI]

    Zhang, Liqing

    of this dot product is given. Simulation results suggest that the overcomplete bubble coding can be achievedLearning Overcomplete Spatiotemporal Bubbles from Natural Image Sequences Libo Ma, and Liqing Zhang, China malibo@sjtu.edu.cn zhang-lq@cs.sjtu.edu.cn Abstract Recently, bubble coding for natural image

  15. Bubble Coalescence DOI: 10.1002/anie.201006552

    E-Print Network [OSTI]

    Chan, Derek Y C

    Bubble Coalescence DOI: 10.1002/anie.201006552 Anomalous Stability of Carbon Dioxide in pH-Controlled Bubble Coalescence** Rico F. Tabor, Derek Y. C. Chan, Franz Grieser, and Raymond R. Dagastine* Gas bubbles are formed as cavities in liquids, their pressure, shape, and deformability determined

  16. On acoustic cavitation of slightly subcritical bubbles Anthony Harkin

    E-Print Network [OSTI]

    Kaper, Tasso J.

    On acoustic cavitation of slightly subcritical bubbles Anthony Harkin Department of Mathematics threshold indicates the onset of quasistatic evolution leading to cavitation for gas bubbles in liquids identifies a critical radius which separates quasistatically stable bubbles from those which would cavitate

  17. Three-dimensional reconstruction of bubble distribution in two-phase bubbly flows with the dynamic programming method

    E-Print Network [OSTI]

    Furukawa, Toru

    2002-01-01T23:59:59.000Z

    by light emitted diodes (LED). A typical shadow image obtained from the experiment is shown in Fig. l. Every bubble in the image has different shape and size. A single bubble phantom cannot be separated from another bubble phantom, in case...

  18. MIMAC: MIcro-tpc MAtrix of Chambers for dark matter directional detection

    E-Print Network [OSTI]

    Santos, D; Bouly, J L; Bourrion, O; Fourel, Ch; Guillaudin, O; Lamblin, J; Mayet, F; Muraz, J F; Richer, J P; Riffard, Q; Lebreton, L; Maire, D; Busto, J; Brunner, J; Fouchez, D

    2013-01-01T23:59:59.000Z

    Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from neutrons, the ultimate background for dark matter direct detection. This strategy requires both a precise measurement of the energy down to a few keV and 3D reconstruction of tracks down to a few mm. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of large pixelized micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The first bi-chamber prototype has been installed at Modane, underground laboratory in June 2012. The first undergournd background events, the gain stability and calibration are shown. The first spectrum of nuclear recoils showing 3D tracks coming from the radon progeny is presented.

  19. Maximal air bubble entrainment at liquid drop impact

    E-Print Network [OSTI]

    Bouwhuis, Wilco; Tran, Tuan; Keij, Diederik L; Winkels, Koen G; Peters, Ivo R; van der Meer, Devaraj; Sun, Chao; Snoeijer, Jacco H; Lohse, Detlef

    2012-01-01T23:59:59.000Z

    At impact of a liquid drop on a solid surface an air bubble can be entrapped. Here we show that two competing effects minimize the (relative) size of this entrained air bubble: For large drop impact velocity and large droplets the inertia of the liquid flattens the entrained bubble, whereas for small impact velocity and small droplets capillary forces minimize the entrained bubble. However, we demonstrate experimentally, theoretically, and numerically that in between there is an optimum, leading to maximal air bubble entrapment. Our results have a strong bearing on various applications in printing technology, microelectronics, immersion lithography, diagnostics, or agriculture.

  20. Track 2: Worker Engagement

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 2: Worker Engagement

  1. Track 3: Exposure Hazards

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 3: Exposure Hazards

  2. Track 9: Quality Assurance

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 9: Quality Assurance

  3. IFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou

    E-Print Network [OSTI]

    Abdou, Mohamed

    IFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou chamber technology testing program in NIF involoving: criteria for evaluation and costs of the more complex experiments in NIF. I. Introduction One important class of issues concerning

  4. Nucleation of vacuum bubbles in Brans-Dicke type theory

    E-Print Network [OSTI]

    Hongsu Kim; Bum-Hoon Lee; Wonwoo Lee; Young Jae Lee; Dong-han Yeom

    2011-07-19T23:59:59.000Z

    In this paper, we explore the nucleation of vacuum bubbles in the Brans-Dicke type theory of gravity. In the Euclidean signature, we evaluate the fields at the vacuum bubbles as solutions of the Euler-Lagrange equations of motion as well as the bubble nucleation probabilities by integrating the Euclidean action. We illustrate three possible ways to obtain vacuum bubbles: true vacuum bubbles for \\omega>-3/2, false vacuum bubbles for \\omegafalse vacuum bubbles for \\omega>-3/2 when the vacuum energy of the false vacuum in the potential of the Einstein frame is less than that of the true vacuum. After the bubble is nucleated at the t=0 surface, we can smoothly interpolate the field combinations to some solutions in the Lorentzian signature and consistently continue their subsequent evolutions. Therefore, we conclude that, in general scalar-tensor theories like this Brans-Dicke type theories, which may include and represent certain features of string theory, vacuum bubbles come in false vacuum bubbles as well as in true vacuum bubbles, as long as a special condition is assumed on the potential.

  5. On the fate of vacuum bubbles on matter backgrounds

    E-Print Network [OSTI]

    Aleksandar Rakic; Dennis Simon; Julian Adamek; Jens C. Niemeyer

    2009-11-19T23:59:59.000Z

    In this letter we discuss cosmological first order phase transitions with de Sitter bubbles nucleating on (inhomogeneous) matter backgrounds. The de Sitter bubble can be a toy model for an inflationary phase of universes like our own. Using the thin wall approximation and the Israel junction method we trace the classical evolution of the formed bubbles within a compound model. We first address homogeneous ambient space (FRW model) and already find that bubbles nucleated in a dust dominated background cannot expand. For an inhomogeneous dust background (LTB model) we describe cases with at least initially expanding bubbles. Yet, an ensuing passage of the bubble wall through ambient curvature inhomogeneities remains unnoticed for observers inside the bubble. Notable effects also for interior observers are found in the case of a rapid background phase transition in a FRW model.

  6. On the fate of vacuum bubbles on matter backgrounds

    E-Print Network [OSTI]

    Rakic, Aleksandar; Adamek, Julian; Niemeyer, Jens C

    2009-01-01T23:59:59.000Z

    In this letter we discuss cosmological first order phase transitions with de Sitter bubbles nucleating on (inhomogeneous) matter backgrounds. The de Sitter bubble can be a toy model for an inflationary phase of universes like our own. Using the thin wall approximation and the Israel junction method we trace the classical evolution of the formed bubbles within a compound model. We first address homogeneous ambient space (FRW model) and already find that bubbles nucleated in a dust dominated background cannot expand. For an inhomogeneous dust background (LTB model) we describe cases with at least initially expanding bubbles. Yet, an ensuing passage of the bubble wall through ambient curvature inhomogeneities remains unnoticed for observers inside the bubble. Notable effects also for interior observers are found in the case of a rapid background phase transition in a FRW model.

  7. Eternal inflation, bubble collisions, and the persistence of memory

    SciTech Connect (OSTI)

    Garriga, Jaume; Guth, Alan H.; Vilenkin, Alexander [Departament de Fisica Fonamental, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain); Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Institute of Cosmology, Department of Physics and Astronomy Tufts University, Medford, Massachusetts 02155 (United States)

    2007-12-15T23:59:59.000Z

    A 'bubble universe' nucleating in an eternally inflating false vacuum will experience, in the course of its expansion, collisions with an infinite number of other bubbles. In an idealized model, we calculate the rate of collisions around an observer inside a given reference bubble. We show that the collision rate violates both the homogeneity and the isotropy of the bubble universe. Each bubble has a center which can be related to 'the beginning of inflation' in the parent false vacuum, and any observer not at the center will see an anisotropic bubble collision rate that peaks in the outward direction. Surprisingly, this memory of the onset of inflation persists no matter how much time elapses before the nucleation of the reference bubble.

  8. A bubble detection system for propellant filling pipeline

    SciTech Connect (OSTI)

    Wen, Wen; Zong, Guanghua; Bi, Shusheng [Robotics Institute, Beihang University, 100191 Beijing (China)

    2014-06-15T23:59:59.000Z

    This paper proposes a bubble detection system based on the ultrasound transmission method, mainly for probing high-speed bubbles in the satellite propellant filling pipeline. First, three common ultrasonic detection methods are compared and the ultrasound transmission method is used in this paper. Then, the ultrasound beam in a vertical pipe is investigated, suggesting that the width of the beam used for detection is usually smaller than the internal diameter of the pipe, which means that when bubbles move close to the pipe wall, they may escape from being detected. A special device is designed to solve this problem. It can generate the spiral flow to force all the bubbles to ascend along the central line of the pipe. In the end, experiments are implemented to evaluate the performance of this system. Bubbles of five different sizes are generated and detected. Experiment results show that the sizes and quantity of bubbles can be estimated by this system. Also, the bubbles of different radii can be distinguished from each other. The numerical relationship between the ultrasound attenuation and the bubble radius is acquired and it can be utilized for estimating the unknown bubble size and measuring the total bubble volume.

  9. Correlation of bubble rise velocity and volume

    SciTech Connect (OSTI)

    Burge, C.

    1991-12-31T23:59:59.000Z

    This project was conducted at Westinghouse`s Savannah River Laboratories (SRL). The goal of SRL is to make certain that the modifications on the reactor are safe for those working at the plant as well as the general public. One of the steps needed to insure safety is the knowledge of the occurrences that result from a plenum pipe breakage. When a plenum pipe breaks, two things occur: air is sucked into the pipe and is trapped in the cooling water; and water used to cool the fuel rods is lost. As a result of these occurrences, the water is slowed down by both the loss in water pressure and the upward force of air bubbles pushing against the downward force of the water. The project required the conducting of tests to find the bubble velocity in an annular ribbed pipe filled with stagnant water. This document discusses the methodology and results of this testing.

  10. Correlation of bubble rise velocity and volume

    SciTech Connect (OSTI)

    Burge, C.

    1991-01-01T23:59:59.000Z

    This project was conducted at Westinghouse's Savannah River Laboratories (SRL). The goal of SRL is to make certain that the modifications on the reactor are safe for those working at the plant as well as the general public. One of the steps needed to insure safety is the knowledge of the occurrences that result from a plenum pipe breakage. When a plenum pipe breaks, two things occur: air is sucked into the pipe and is trapped in the cooling water; and water used to cool the fuel rods is lost. As a result of these occurrences, the water is slowed down by both the loss in water pressure and the upward force of air bubbles pushing against the downward force of the water. The project required the conducting of tests to find the bubble velocity in an annular ribbed pipe filled with stagnant water. This document discusses the methodology and results of this testing.

  11. Bubbling the Newly Grown Black Ring Hair

    E-Print Network [OSTI]

    Orestis Vasilakis

    2012-02-08T23:59:59.000Z

    New families of BPS black ring solutions with four electric and four dipole magnetic charges have recently been explicitly constructed and uplifted to M-theory. These solutions were found to belong to a CFT with central charge different compared to the one of the STU model. Because of their importance to AdS/CFT, here we give the microstate description of these geometries in terms of topological bubbles and supertubes. The fourth charge results in an additional flux through the topological cycles that resolve the brane singularities. The analog of these solutions in the IIB frame yield a generalized regular supertube with three electric charges and one dipole charge. Direct comparison is also made with the previously-known bubbled geometries.

  12. Improving neutron dosimetry using bubble detector technology

    SciTech Connect (OSTI)

    Buckner, M.A.

    1993-02-01T23:59:59.000Z

    Providing accurate neutron dosimetry for a variety of neutron energy spectra is a formidable task for any dosimetry system. Unless something is known about the neutron spectrum prior to processing the dosimeter, the calculated dose may vary greatly from that actually encountered; that is until now. The entrance of bubble detector technology into the field of neutron dosimetry has eliminated the necessity of having an a priori knowledge of the neutron energy spectra. Recently, a new approach in measuring personnel neutron dose equivalent was developed at Oak Ridge National Laboratory. By using bubble detectors in combination with current thermoluminescent dosimeters (TLDs) as a Combination Personnel Neutron Dosimeter (CPND), not only is it possible to provide accurate dose equivalent results, but a simple four-interval neutron energy spectrum is obtained as well. The components of the CPND are a Harshaw albedo TLD and two bubble detectors with theoretical energy thresholds of 100 key and 1500 keV. Presented are (1) a synoptic history surrounding emergence of bubble detector technology, (2) a brief overview of the current theory on mechanisms of interaction, (3) the data and analysis process involved in refining the response functions, (4) performance evaluation of the original CPND and a reevaluation of the same data under the modified method, (5) the procedure used to determine the reference values of component fluence and dose equivalent for field assessment, (6) analysis of the after-modification results, (7) a critique of some currently held assumptions, offering some alternative explanations, and (8) thoughts concerning potential applications and directions for future research.

  13. Simulation of chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Simulation of Chamber Transport for Heavy-Ion Fusion W. M.et al. , “Modeling Chamber Transport for Heavy-Ion Fusion,”et al. , "Chamber Transport of `Foot' Pulses for Heavy-Ion

  14. Intense ion beam propagation in a reactor sized chamber

    E-Print Network [OSTI]

    Vay, J.L.; Deutsch, C.

    2000-01-01T23:59:59.000Z

    beams in a heavy ion fusion reactor chamber filled with lowIon Fusion, Intense Ion Beams, Reaction Chamber. P.A.C.S.heavy ion beam propagation in the reaction chamber, Fus.

  15. Modeling chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Modeling Chamber Transport for Heavy-Ion Fusion W. M. Sharp,Peterson, "Chamber Transport of 'Foot' Pulses for Heavy-Ionstate of beam ions. Although several chamber- transport

  16. Chamber transport of "foot" pulses for heavy-ion fusion

    E-Print Network [OSTI]

    Sharp, W.M.; Callahan-Miller, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.

    2002-01-01T23:59:59.000Z

    Neutralization on Heavy-Ion-Fusion Chamber Transport," to beChamber transport of "foot" pulses for heavy-ion fusion W.chamber-transport effectiveness is the fraction of enclosed beam ions

  17. Allostery through protein-induced DNA bubbles

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

    Traverso, Joseph J.; Manoranjan, Valipuram S.; Bishop, A. R.; Rasmussen, Kim Ø.; Voulgarakis, Nikolaos K.

    2015-03-12T23:59:59.000Z

    Allostery through DNA is increasingly recognized as an important modulator of DNA functions. Here, we show that the coalescence of protein-induced DNA bubbles can mediate allosteric interactions that drive protein aggregation. We propose that such allostery may regulate DNA's flexibility and the assembly of the transcription machinery. Mitochondrial transcription factor A (TFAM), a dual-function protein involved in mitochondrial DNA (mtDNA) packaging and transcription initiation, is an ideal candidate to test such a hypothesis owing to its ability to locally unwind the double helix. Numerical simulations demonstrate that the coalescence of TFAM-induced bubbles can explain experimentally observed TFAM oligomerization. The resultingmore »melted DNA segment, approximately 10 base pairs long, around the joints of the oligomers act as flexible hinges, which explains the efficiency of TFAM in compacting DNA. Since mitochondrial polymerase (mitoRNAP) is involved in melting the transcription bubble, TFAM may use the same allosteric interaction to both recruit mitoRNAP and initiate transcription.« less

  18. Track Co-ordinators Guide Track Co-ordinators Guide

    E-Print Network [OSTI]

    Track Co-ordinators Guide CERN #12;Track Co-ordinators Guide by CERN #12;Table of Contents 1. Track Co-ordinators Guide ..................................................................................................................1 1.1. Track Co

  19. Mesoscale modeling of intergranular bubble percolation in nuclear fuels

    SciTech Connect (OSTI)

    Millett, Paul C.; Tonks, Michael; Biner, S. B. [Nuclear Fuels and Materials, Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States)

    2012-04-15T23:59:59.000Z

    Phase-field simulations are used to examine the variability of intergranular fission gas bubble growth and percolation on uranium dioxide grain boundaries on a mesoscopic length scale. Three key parameters are systematically varied in this study: the contact angle (or dihedral angle) defining the bubble shape, the initial bubble density on the grain boundary plane, and the ratio of the gas diffusivity on the grain boundary versus the grain interiors. The simulation results agree well with previous experimental data obtained for bubble densities and average bubble areas during coalescence events. Interestingly, the rate of percolation is found to be highly variable, with a large dependency on the contact angle and the initial bubble density and little-to-no dependency on the grain boundary gas diffusivity.

  20. MESOSCALE MODELING OF INTERGRANULAR BUBBLE PERCOLATION IN NUCLEAR FUELS

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks; S. B. Biner

    2012-04-01T23:59:59.000Z

    Phase-field simulations are used to examine the variability of intergranular fission gas bubble growth and percolation on uranium dioxide grain boundaries on a mesoscopic length scale. Three key parameters are systematically varied in this study: the contact angle (or dihedral angle) defining the bubble shape, the initial bubble density on the grain boundary plane, and the ratio of the gas diffusivity on the grain boundary versus the grain interiors. The simulation results agree well with previous experimental data obtained for bubble densities and average bubble areas during coalescence events. Interestingly, the rate of percolation is found to be highly variable, with a large dependency on the contact angle and the initial bubble density, and little-to-no dependency on the grain boundary gas diffusivity.

  1. An environmental sample chamber for reliable scanning transmission...

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

    environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor. An environmental sample chamber for reliable scanning transmission...

  2. Mini-PROTEAN Multi-Casting Chamber

    E-Print Network [OSTI]

    Raizada, Manish N.

    ºC for future use. 1.2 Specifications Materials of construction Clamps Glass filled polycarbonate Casting chamber, sealing plate Molded polycarbonate Gasket Silicone tubing Overall size 10 cm x 10 cm x 16

  3. Formation mechanisms of combustion chamber deposits

    E-Print Network [OSTI]

    O'Brien, Christopher J. (Christopher John)

    2001-01-01T23:59:59.000Z

    Combustion chamber deposits are found in virtually all internal combustion engines after a few hundred hours of operation. Deposits form on cylinder, piston, and head surfaces that are in contact with fuel-air mixture ...

  4. Bubble coalescence dynamics and supersaturation in electrolytic gas evolution

    SciTech Connect (OSTI)

    Stover, R.L. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

    1996-08-01T23:59:59.000Z

    The apparatus and procedures developed in this research permit the observation of electrolytic bubble coalescence, which heretofore has not been possible. The influence of bubble size, electrolyte viscosity, surface tension, gas type, and pH on bubble coalescence was examined. The Navier-Stokes equations with free surface boundary conditions were solved numerically for the full range of experimental variables that were examined. Based on this study, the following mechanism for bubble coalescence emerges: when two gas bubbles coalesce, the surface energy decreases as the curvature and surface area of the resultant bubble decrease, and the energy is imparted into the surrounding liquid. The initial motion is driven by the surface tension and slowed by the inertia and viscosity of the surrounding fluid. The initial velocity of the interface is approximately proportional to the square root of the surface tension and inversely proportional to the square root of the bubble radius. Fluid inertia sustains the oblate/prolate oscillations of the resultant bubble. The period of the oscillations varies with the bubble radius raised to the 3/2 power and inversely with the square root of the surface tension. Viscous resistance dampens the oscillations at a rate proportional to the viscosity and inversely proportional to the square of the bubble radius. The numerical simulations were consistent with most of the experimental results. The differences between the computed and measured saddle point decelerations and periods suggest that the surface tension in the experiments may have changed during each run. By adjusting the surface tension in the simulation, a good fit was obtained for the 150-{micro}m diameter bubbles. The simulations fit the experiments on larger bubbles with very little adjustment of surface tension. A more focused analysis should be done to elucidate the phenomena that occur in the receding liquid film immediately following rupture.

  5. Dynamics of false vacuum bubbles with nonminimal coupling

    E-Print Network [OSTI]

    Bum-Hoon Lee; Chul H. Lee; Wonwoo Lee; Siyoung Nam; Chanyong Park

    2008-03-07T23:59:59.000Z

    We study the dynamics of false vacuum bubbles. A nonminimally coupled scalar field gives rise to the effect of negative tension. The mass of a false vacuum bubble from outside observer's point of view can be positive, zero, or negative. The interior false vacuum has de Sitter geometry, while the exterior true vacuum background can have geometry depending on the vacuum energy. We show that there exist expanding false vacuum bubbles without the initial singularity in the past.

  6. Dynamics of false vacuum bubbles with nonminimal coupling

    SciTech Connect (OSTI)

    Lee, Bum-Hoon [Department of Physics, Sogang University, Seoul 121-742 (Korea, Republic of); Center for Quantum Spacetime, Sogang University, Seoul 121-742 (Korea, Republic of); Lee, Chul H. [Department of Physics, and BK21 Division of Advanced Research and Education in Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Lee, Wonwoo [Research Institute for Basic Science, Sogang University, Seoul 121-742 (Korea, Republic of); Nam, Siyoung; Park, Chanyong [Center for Quantum Spacetime, Sogang University, Seoul 121-742 (Korea, Republic of)

    2008-03-15T23:59:59.000Z

    We study the dynamics of false vacuum bubbles. A nonminimally coupled scalar field gives rise to the effect of negative tension. The mass of a false vacuum bubble from an outside observer's point of view can be positive, zero, or negative. The interior false vacuum has de Sitter geometry, while the exterior true vacuum background can have geometry depending on the vacuum energy. We show that there exist expanding false vacuum bubbles without the initial singularity in the past.

  7. Solar tracking apparatus

    DOE Patents [OSTI]

    Hammons, Burrell E. (Albuquerque, NM)

    1980-01-01T23:59:59.000Z

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxiliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  8. Numerical Simulation of Bubble Formation in Co-Flowing Mercury

    SciTech Connect (OSTI)

    Abdou, Ashraf A [ORNL; Wendel, Mark W [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL

    2008-01-01T23:59:59.000Z

    In this work, we present computational fluid dynamics (CFD) simulations of helium bubble formation and detachment at a submerged needle in stagnant and co-flowing mercury. Since mercury is opaque, visualization of internal gas bubbles was done with proton radiography (pRad) at the Los Alamos Neutron Science Center (LANSCE2). The acoustic waves emitted at the time of detachment and during subsequent oscillations of the bubble were recorded with a microphone. The Volume of Fluid (VOF) model was used to simulate the unsteady two-phase flow of gas injection in mercury. The VOF model is validated by comparing detailed bubble sizes and shapes at various stages of the bubble growth and detachment, with the experimental measurements at different gas flow rates and mercury velocities. The experimental and computational results show a two-stage bubble formation. The first stage involves growing bubble around the needle, and the second follows as the buoyancy overcomes wall adhesion. The comparison of predicted and measured bubble sizes and shapes at various stages of the bubble growth and detachment is in good agreement.

  9. COLD BUBBLE FORMATION DURING TOKAMAK DENSITY LIMIT DISRUPTIONS

    E-Print Network [OSTI]

    Howard, John

    COLD BUBBLE FORMATION DURING TOKAMAK DENSITY LIMIT DISRUPTIONS J. HOWARD, M. PERSSON* Plasma Research Laboratory, Research School of Physical Sciences, Australian National University, Canberra

  10. Thermonuclear Supernovae: Is Deflagration Triggered by Floating Bubbles?

    E-Print Network [OSTI]

    Eduardo Bravo; Domingo Garcia-Senz

    2002-11-13T23:59:59.000Z

    In recent years, it has become clear from multidimensional simulations that the outcome of deflagrations depends strongly on the initial configuration of the flame. We have studied under which conditions this configuration could consist of a number of scattered, isolated, hot bubbles. Afterwards, we have calculated the evolution of deflagrations starting from different numbers of bubbles. We have found that starting from 30 bubbles a mild explosion is produced M(Ni56)=0.56 solar masses, while starting from 10 bubbles the star becomes only marginally unbound (K = 0.05 foes).

  11. Detecting vapour bubbles in simulations of metastable water

    SciTech Connect (OSTI)

    González, Miguel A.; Abascal, Jose L. F.; Valeriani, Chantal, E-mail: christoph.dellago@univie.ac.at, E-mail: cvaleriani@quim.ucm.es [Departamento de Química Fsica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Menzl, Georg; Geiger, Philipp; Dellago, Christoph, E-mail: christoph.dellago@univie.ac.at, E-mail: cvaleriani@quim.ucm.es [Faculty of Physics and Center for Computational Materials Science, University of Vienna, Boltzmanngasse 5, 1090 Vienna (Austria); Aragones, Juan L. [Departamento de Química Fsica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Caupin, Frederic [Laboratoire de Physique de la Matiere Condensee et Nanostructures, Universite Claude Bernard, Lyon 1 et CNRS, Institut Universitaire de France, 43 boulevard du 11 novembre 1918, 69100 Villeurbanne (France)

    2014-11-14T23:59:59.000Z

    The investigation of cavitation in metastable liquids with molecular simulations requires an appropriate definition of the volume of the vapour bubble forming within the metastable liquid phase. Commonly used approaches for bubble detection exhibit two significant flaws: first, when applied to water they often identify the voids within the hydrogen bond network as bubbles thus masking the signature of emerging bubbles and, second, they lack thermodynamic consistency. Here, we present two grid-based methods, the M-method and the V-method, to detect bubbles in metastable water specifically designed to address these shortcomings. The M-method incorporates information about neighbouring grid cells to distinguish between liquid- and vapour-like cells, which allows for a very sensitive detection of small bubbles and high spatial resolution of the detected bubbles. The V-method is calibrated such that its estimates for the bubble volume correspond to the average change in system volume and are thus thermodynamically consistent. Both methods are computationally inexpensive such that they can be used in molecular dynamics and Monte Carlo simulations of cavitation. We illustrate them by computing the free energy barrier and the size of the critical bubble for cavitation in water at negative pressure.

  12. Experimental Investigation of Bubble Formation in Micro-devices N. Dietrich, S. Poncin & Huai Z. Li

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of bubbles serves various applications in industrial processes such as the generation of biogas bubbles by anaerobic sludge granules in a bioreactor (Wu et al., 2006), bubble nucleation in polymer devolatization

  13. Calibration of Muon Reconstruction Algorithms Using an External Muon Tracking System at the Sudbury Neutrino Observatory

    E-Print Network [OSTI]

    SNO Collaboration

    2011-05-06T23:59:59.000Z

    To help constrain the algorithms used in reconstructing high-energy muon events incident on the Sudbury Neutrino Observatory (SNO), a muon tracking system was installed. The system consisted of four planes of wire chambers, which were triggered by scintillator panels. The system was integrated with SNO's main data acquisition system and took data for a total of 95 live days. Using cosmic-ray events reconstructed in both the wire chambers and in SNO's water Cherenkov detector, the external muon tracking system was able to constrain the uncertainty on the muon direction to better than 0.6 degrees.

  14. Main Chamber Pressure why do we care about it?

    E-Print Network [OSTI]

    Pitcher, C. S.

    .main chamber recycling 3.ion flux to the upper part of the outer plate 4.upper divertor leakage #12Main Chamber Pressure why do we care about it? - neutrals in the main chamber imply a particle-surface interaction there which may result in impurity production and erosion - neutrals in the main chamber may

  15. Gas Bubble Formation in Stagnant and Flowing Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL] [ORNL; Abdou, Ashraf A [ORNL] [ORNL; Riemer, Bernie [ORNL] [ORNL; Felde, David K [ORNL] [ORNL

    2007-01-01T23:59:59.000Z

    Investigations in the area of two-phase flow at the Oak Ridge National Laboratory's (ORNL) Spallation Neutron Source (SNS) facility are progressing. It is expected that the target vessel lifetime could be extended by introducing gas into the liquid mercury target. As part of an effort to validate the two-phase computational fluid dynamics (CFD) model, simulations and experiments of gas injection in stagnant and flowing mercury have been completed. The volume of fluid (VOF) method as implemented in ANSYS-CFX, was used to simulate the unsteady two-phase flow of gas injection into stagnant mercury. Bubbles produced at the upwards-oriented vertical gas injector were measured with proton radiography at the Los Alamos Neutron Science Center. The comparison of the CFD results to the radiographic images shows good agreement for bubble sizes and shapes at various stages of the bubble growth, detachment, and gravitational rise. Although several gas flows were measured, this paper focuses on the case with a gas flow rate of 8 cc/min through the 100-micron-diameter injector needle. The acoustic waves emitted due to the detachment of the bubble and during subsequent bubble oscillations were recorded with a microphone, providing a precise measurement of the bubble sizes. As the mercury flow rate increases, the drag force causes earlier bubble detachment and therefore smaller bubbles.

  16. Experimental setup for the investigation of bubble mediated gas exchange

    E-Print Network [OSTI]

    Jaehne, Bernd

    time. For small bubbles, the gas exchange is therefore directly related to the volume fluxExperimental setup for the investigation of bubble mediated gas exchange Wolfgang Mischler1,2 , Roland Rocholz2 and Bernd J¨ahne1,2 1 Heidelberg Collaboratory for Image Processing, University

  17. Picosecond and nanosecond polychromatic pumpprobe studies of bubble

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Picosecond and nanosecond polychromatic pump­probe studies of bubble growth in carbon in carbon-nanotube suspensions, whose origin lies in a strong nonlinear scattering due to sol- vent vapor bubbles and sublimation of the nanotubes, is investigated in the picosecond and nanosecond re- gimes

  18. RESEARCH ARTICLE Bubble growth in visco-elastic magma: implications

    E-Print Network [OSTI]

    Lyakhovsky, Vladimir

    RESEARCH ARTICLE Bubble growth in visco-elastic magma: implications to magma fragmentation modulus, bubble growth is slow and follows an exponential law in a viscous growth regime, while for low friction and the Mohr-Coulomb failure theory, and a strain related one based on fibre elongation

  19. Spatial Separation of Cavitating Bubble Populations: The Nanodroplet Injection Model

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    the blue-white bubble cloud; at higher intensities, the blue-white emission is well separated spatially@illinois.edu Multibubble sonoluminescence (MBSL), the light emitted during the implosive collapse of clouds of bubbles observe two spatially separate types of MBSL from 0.1 M Na2SO4 in 95% sulfuric acid: (1) blue-white

  20. The evolution of false vacuum bubbles in radiating metrics

    SciTech Connect (OSTI)

    Larsen, K.M.

    1990-01-01T23:59:59.000Z

    The equations of motion for false vacuum bubbles in Vaidya-Mallett metrics are derived and numerically solved. It is demonstrated that the evolution of the bubble differs from the standard Schwarzschild-de Sitter results. The luminosity as measured by an external observer is found to deviate from the normal Hawking luminosity, thus producing a signature for the existence of the child universe.

  1. Asymmetric bubble disconnection: persistent vibration evolves into smooth contact

    E-Print Network [OSTI]

    Zhang, Wendy

    the amount of water rushing inwards decreases to 0 as the neck radius goes to 0, all the kinetic energy: Bubble disconnection dynamics. (a) Experimental setup: an air bubble (dark area) is submerged under water: February 2, 2009) Focusing a finite amount of energy dynamically into a vanishingly small amount

  2. Topology Changing Transitions in Bubbling Geometries

    SciTech Connect (OSTI)

    Horava, Petr; Shepard, Peter G.

    2005-02-15T23:59:59.000Z

    Topological transitions in bubbling half-BPS Type IIB geometries with SO(4) x SO(4) symmetry can be decomposed into a sequence of n elementary transitions. The half-BPS solution that describes the elementary transition is seeded by a phase space distribution of fermions filling two diagonal quadrants. We study the geometry of this solution in some detail. We show that this solution can be interpreted as a time dependent geometry, interpolating between two asymptotic pp-waves in the far past and the far future. The singular solution at the transition can be resolved in two different ways, related by the particle-hole duality in the effective fermion description. Some universal features of the topology change are governed by two-dimensional Type 0B string theory, whose double scaling limit corresponds to the Penrose limit of AdS_5 x S5 at topological transition. In addition, we present the full class of geometries describing the vicinity of the most general localized classical singularity that can occur in this class of half-BPS bubbling geometries.

  3. A Time Projection Chamber for High Accuracy and Precision Fission Cross-Section Measurements

    SciTech Connect (OSTI)

    T. Hill; K. Jewell; M. Heffner; D. Carter; M. Cunningham; V. Riot; J. Ruz; S. Sangiorgio; B. Seilhan; L. Snyder; D. M. Asner; S. Stave; G. Tatishvili; L. Wood; R. G. Baker; J. L. Klay; R. Kudo; S. Barrett; J. King; M. Leonard; W. Loveland; L. Yao; C. Brune; S. Grimes; N. Kornilov; T. N. Massey; J. Bundgaard; D. L. Duke; U. Greife; U. Hager; E. Burgett; J. Deaven; V. Kleinrath; C. McGrath; B. Wendt; N. Hertel; D. Isenhower; N. Pickle; H. Qu; S. Sharma; R. T. Thornton; D. Tovwell; R. S. Towell; S.

    2014-09-01T23:59:59.000Z

    The fission Time Projection Chamber (fissionTPC) is a compact (15 cm diameter) two-chamber MICROMEGAS TPC designed to make precision cross-section measurements of neutron-induced fission. The actinide targets are placed on the central cathode and irradiated with a neutron beam that passes axially through the TPC inducing fission in the target. The 4p acceptance for fission fragments and complete charged particle track reconstruction are powerful features of the fissionTPC which will be used to measure fission cross-sections and examine the associated systematic errors. This paper provides a detailed description of the design requirements, the design solutions, and the initial performance of the fissionTPC.

  4. Recent Advances in Chamber Science and Technology

    E-Print Network [OSTI]

    Abdou, Mohamed

    with RAFS Advanced: He gas cooling system with SiC/SiC Research on several advanced concepts: FLiBe, Li, Li cooled blanket system for higher thermal efficiency - High temperature gas cooled blanket system with Si Programs on Chamber/Blanket · Recent Progress on Liquid Walls - IFE & MFE - Basic Principles - Plasma

  5. Lifetime tests for MAC vertex chamber

    SciTech Connect (OSTI)

    Nelson, H.N.

    1986-07-01T23:59:59.000Z

    A vertex chamber for MAC was proposed to increase precision in the measurement of the B hadron and tau lepton lifetimes. Thin-walled aluminized mylar drift tubes were used for detector elements. A study of radiation hardness was conducted under the conditions of the proposed design using different gases and different operating conditions. (LEW)

  6. Inertial confinement fusion based on the ion-bubble trigger

    SciTech Connect (OSTI)

    Jafari, S., E-mail: SJafari@guilan.ac.ir; Nilkar, M.; Ghasemizad, A. [Department of Physics, University of Guilan, Rasht 41335-1914 (Iran, Islamic Republic of); Mehdian, H. [Department of Physics and Institute for Plasma Research, Tarbiat Moallem University, Tehran 15614 (Iran, Islamic Republic of)

    2014-10-15T23:59:59.000Z

    Triggering the ion-bubble in an inertial confinement fusion, we have developed a novel scheme for the fast ignition. This scheme relies on the plasma cavitation by the wake of an intense laser pulse to generate an ion-bubble. The bubble acts both as an intense electron accelerator and as an electron wiggler. Consequently, the accelerated electrons trapped in the bubble can emit an intense tunable laser light. This light can be absorbed by an ablation layer on the outside surface of the ignition capsule, which subsequently drills it and thereby produces a guide channel in the pellet. Finally, the relativistic electron beam created in the bubble is guided through the channel to the high density core igniting the fusion fuel. The normalized beam intensity and beam energy required for triggering the ignition have been calculated when core is heated by the e-beam. In addition, through solving the momentum transfer, continuity and wave equations, a dispersion relation for the electromagnetic and space-charge waves has been analytically derived. The variations of growth rate with the ion-bubble density and electron beam energy have been illustrated. It is found that the growth rates of instability are significantly controlled by the ions concentration and the e-beam energy in the bubble.

  7. Moduli vacuum bubbles produced by evaporating black holes

    SciTech Connect (OSTI)

    Morris, J. R. [Physics Department, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States)

    2007-10-15T23:59:59.000Z

    We consider a model with a toroidally compactified extra dimension giving rise to a temperature-dependent 4D effective potential with one-loop contributions due to the Casimir effect, along with a 5D cosmological constant. The forms of the effective potential at low and high temperatures indicate a possibility for the formation of a domain wall bubble, formed by the modulus scalar field, surrounding an evaporating black hole. This is viewed as an example of a recently proposed black hole vacuum bubble arising from matter-sourced moduli fields in the vicinity of an evaporating black hole [D. Green, E. Silverstein, and D. Starr, Phys. Rev. D 74, 024004 (2006)]. The black hole bubble can be highly opaque to lower-energy particles and photons, and thereby entrap them within. For high-temperature black holes, there may also be a symmetry-breaking black hole bubble of false vacuum of the type previously conjectured by Moss [I. G. Moss, Phys. Rev. D 32, 1333 (1985)], tending to reflect low-energy particles from its wall. A double bubble composed of these two different types of bubble may form around the black hole, altering the hole's emission spectrum that reaches outside observers. Smaller mass black holes that have already evaporated away could have left vacuum bubbles behind that contribute to the dark matter.

  8. High-voltage crowbar protection for the large CDF axial drift chamber

    SciTech Connect (OSTI)

    Binkley, M.; Mukherjee, A.; Stuermer, W.; Wagner, R.L.; /Fermilab

    2004-01-01T23:59:59.000Z

    The Central Outer Tracker (COT) is a big cylindrical drift chamber that provides charged particle tracking for the Collider Detector at Fermilab experiment. To protect the COT, the large stored energy in the high voltage system needs to be removed quickly when a problem is sensed. For the high voltage switch, a special-order silicon-controlled-rectifier was chosen over more readily available integrated gate bipolar transistors because of layout and reliability questions. The considerations concerning the high voltage switch, the prototype performance, and the experience of more than two years of running are described.

  9. Growth of a susy bubble: inhomogeneity effects

    E-Print Network [OSTI]

    L. Clavelli

    2005-06-22T23:59:59.000Z

    In a dense star, the Pauli exclusion principle functions as an enormous energy storage mechanism. Supersymmetry could provide a way to recapture this energy. If there is a transition to an exactly supersymmetric (susy) phase, the trapped energy can be released with consequences similar to gamma ray burst observations. Previous zeroth order calculations have been based on the behavior in a prototypical white dwarf of solar mass and earth radius (such as Sirius B) and have neglected density inhomogeneity. In this article we show that the effects of density inhomogeneity and of variations in masses and radii are substantial enough to encourage further exploration of the susy star model. In addition, the effects discussed here have possible applications to the growth of bubbles in other phase transition models in dense matter.

  10. Measurements of Gas Bubble Size Distributions in Flowing Liquid Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Riemer, Bernie [ORNL; Abdou, Ashraf A [ORNL

    2012-01-01T23:59:59.000Z

    ABSTRACT Pressure waves created in liquid mercury pulsed spallation targets have been shown to induce cavitation damage on the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, measuring such a population in mercury is difficult since it is opaque and the mercury is involved in a turbulent flow. Ultrasonic measurements have been attempted on these types of flows, but the flow noise can interfere with the measurement, and the results are unverifiable and often unrealistic. Recently, a flow loop was built and operated at Oak Ridge National Labarotory to assess the capability of various bubbler designs to deliver an adequate population of bubbles to mitigate cavitation damage. The invented diagnostic technique involves flowing the mercury with entrained gas bubbles in a steady state through a horizontal piping section with a glass-window observation port located on the top. The mercury flow is then suddenly stopped and the bubbles are allowed to settle on the glass due to buoyancy. Using a bright-field illumination and a high-speed camera, the arriving bubbles are detected and counted, and then the images can be processed to determine the bubble populations. After using this technique to collect data on each bubbler, bubble size distributions were built for the purpose of quantifying bubbler performance, allowing the selection of the best bubbler options. This paper presents the novel procedure, photographic technique, sample visual results and some example bubble size distributions. The best bubbler options were subsequently used in proton beam irradiation tests performed at the Los Alamos National Laboratory. The cavitation damage results from the irradiated test plates in contact with the mercury are available for correlation with the bubble populations. The most effective mitigating population can now be designed into prototypical geometries for implementation into an actual SNS target.

  11. The singularity at the tip of the rising plane bubble: The case of nonzero surface tension

    E-Print Network [OSTI]

    Daripa, Prabir

    The singularity at the tip of the rising plane bubble: The case of nonzero surface tension Prabir pointed bubble in the presenceof surface tension. These bubbles have been recently obtained by Vanden to find the apexangle as a function of the speedof the bubbles for a fixed value of surface tension

  12. Large scale tracking algorithms.

    SciTech Connect (OSTI)

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01T23:59:59.000Z

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  13. Induced radiation processes in single-bubble sonoluminescence

    E-Print Network [OSTI]

    Prigara, F V

    2005-01-01T23:59:59.000Z

    According to the recent revision of the theory of thermal radiation, thermal black-body radiation has an induced origin. We show that in single-bubble sonoluminescence thermal radiation is emitted by a spherical resonator, coincident with the sonoluminescing bubble itself, instead of the ensemble of elementary resonators emitting thermal black-body radiation in the case of open gaseous media. For a given wavelength, the diameter of the resonator is fixed, and this explains the very high constancy in phase of light flashes from the sonoluminesing bubble, which is better than the constancy of period of a driving acoustic wave.

  14. The nucleation of false vacuum bubbles with compact geometries

    E-Print Network [OSTI]

    Bum-Hoon Lee; Chul H. Lee; Wonwoo Lee; Changheon Oh

    2013-11-18T23:59:59.000Z

    We investigate the nucleation process for the possible types of vacuum bubbles. We classify false vacuum bubbles of a self-gravitating scalar field with compact geometries. We show that there exist numerical solutions representing the tunneling from the true vacuum state to the false vacuum state. The solutions are possible only gravity taken into account. We present the analytic computations for the radius and nucleation rate of a vacuum bubble using the thin-wall approximation. We discuss possible cosmological implications of our solutions.

  15. Dynamics of false vacuum bubbles in Brans-Dicke theory

    E-Print Network [OSTI]

    Bum-Hoon Lee; Wonwoo Lee; Dong-han Yeom

    2011-01-11T23:59:59.000Z

    We study the dynamics of false vacuum bubbles in the Brans-Dicke theory of gravity by using the thin shell or thin wall approximation. We consider a false vacuum bubble that has a different value for the Brans-Dicke field between the inside false vacuum region and the outside true vacuum region. Within a certain limit of field values, the difference of field values makes the effective tension of the shell negative. This allows new expanding false vacuum bubbles to be seen by the outside observer, which are disallowed in Einstein gravity.

  16. Dynamics of false vacuum bubbles in Brans-Dicke theory

    SciTech Connect (OSTI)

    Lee, Bum-Hoon; Lee, Wonwoo [Department of Physics and BK21 Division and Center for Quantum Spacetime, Sogang University, Seoul 121-742 (Korea, Republic of); Yeom, Dong-han, E-mail: bhl@sogang.ac.kr, E-mail: warrior@sogang.ac.kr, E-mail: innocent@muon.kaist.ac.kr [Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of)

    2011-01-01T23:59:59.000Z

    We study the dynamics of false vacuum bubbles in the Brans-Dicke theory of gravity by using the thin shell or thin wall approximation. We consider a false vacuum bubble that has a different value for the Brans-Dicke field between the inside false vacuum region and the outside true vacuum region. Within a certain limit of field values, the difference of field values makes the effective tension of the shell negative. This allows new expanding false vacuum bubbles to be seen by the outside observer, which are disallowed in Einstein gravity.

  17. The Milky Way Project: Leveraging Citizen Science and Machine Learning to Detect Interstellar Bubbles

    E-Print Network [OSTI]

    Beaumont, Christopher; Williams, Jonathan; Kendrew, Sarah; Simpson, Robert

    2014-01-01T23:59:59.000Z

    We present Brut, an algorithm to identify bubbles in infrared images of the Galactic midplane. Brut is based on the Random Forest algorithm, and uses bubbles identified by >35,000 citizen scientists from the Milky Way Project to discover the identifying characteristics of bubbles in images from the Spitzer Space Telescope. We demonstrate that Brut's ability to identify bubbles is comparable to expert astronomers. We use Brut to re-assess the bubbles in the Milky Way Project catalog, and find that 10-30% of the objects in this catalog are non-bubble interlopers. Relative to these interlopers, high-reliability bubbles are more confined to the mid plane, and display a stronger excess of Young Stellar Objects along and within bubble rims. Furthermore, Brut is able to discover bubbles missed by previous searches -- particularly bubbles near bright sources which have low contrast relative to their surroundings. Brut demonstrates the synergies that exist between citizen scientists, professional scientists, and machi...

  18. The experimental feature on the data of the primary proton identification in stratospheric X-ray emulsion chambers at energies >10 TeV (RUNJOB experiment)

    E-Print Network [OSTI]

    I. S. Zayarnaya

    2006-10-02T23:59:59.000Z

    The RUNJOB balloon-born emulsion chamber experiments have been carried out for investigating the composition and energy spectra of primary cosmic rays at energies 10-1000 TeV/nucleon. On the data of the treatment of RUNJOB` X-ray emulsion chambers exposed since 1995 to 1999 year about 50 % proton tracks were identified. In remained half of the events from proton group the one charged primary tracks were not found in the search area determined with high accuracy by the triangulation method using the several background heavy tracks. Considered methodical reasons in this paper could not explain this experimental result. The one from the probable physical reasons that is the neutrons in cosmic ray flux does not explain it too.

  19. Small Gas Bubble Experiment for Mitigation of Cavitation Damage and Pressure Waves in Short-pulse Mercury Spallation Targets

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL] [ORNL; Felde, David K [ORNL] [ORNL; Sangrey, Robert L [ORNL] [ORNL; Abdou, Ashraf A [ORNL] [ORNL; West, David L [ORNL] [ORNL; Shea, Thomas J [ORNL] [ORNL; Hasegawa, Shoichi [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Kogawa, Hiroyuki [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Naoe, Dr. Takashi [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Farny, Dr. Caleb H. [Boston University] [Boston University; Kaminsky, Andrew L [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    Populations of small helium gas bubbles were introduced into a flowing mercury experiment test loop to evaluate mitigation of beam-pulse induced cavitation damage and pressure waves. The test loop was developed and thoroughly tested at the Spallation Neutron Source (SNS) prior to irradiations at the Los Alamos Neutron Science Center - Weapons Neutron Research Center (LANSCE-WNR) facility. Twelve candidate bubblers were evaluated over a range of mercury flow and gas injection rates by use of a novel optical measurement technique that accurately assessed the generated bubble size distributions. Final selection for irradiation testing included two variations of a swirl bubbler provided by Japan Proton Accelerator Research Complex (J-PARC) collaborators and one orifice bubbler developed at SNS. Bubble populations of interest consisted of sizes up to 150 m in radius with achieved gas void fractions in the 10^-5 to 10^-4 range. The nominal WNR beam pulse used for the experiment created energy deposition in the mercury comparable to SNS pulses operating at 2.5 MW. Nineteen test conditions were completed each with 100 pulses, including variations on mercury flow, gas injection and protons per pulse. The principal measure of cavitation damage mitigation was surface damage assessment on test specimens that were manually replaced for each test condition. Damage assessment was done after radiation decay and decontamination by optical and laser profiling microscopy with damaged area fraction and maximum pit depth being the more valued results. Damage was reduced by flow alone; the best mitigation from bubble injection was between half and a quarter that of flow alone. Other data collected included surface motion tracking by three laser Doppler vibrometers (LDV), loop wall dynamic strain, beam diagnostics for charge and beam profile assessment, embedded hydrophones and pressure sensors, and sound measurement by a suite of conventional and contact microphones.

  20. On-Site Wastewater Treatment Systems: Leaching Chambers

    E-Print Network [OSTI]

    Lesikar, Bruce J.

    2000-02-04T23:59:59.000Z

    Leaching chambers distribute treated wastewater into the soil. This publication lists the advantages and disadvantages of leaching chamber systems, explains how to maintain them and gives estimates of costs....

  1. Heart-shaped bubbles rising in anisotropic liquids

    E-Print Network [OSTI]

    2007-04-27T23:59:59.000Z

    Apr 27, 2007 ... fluid, and would rise in the wake of the ball Fig. 1 . Such a ..... non-Newtonian fluids around bubbles and its connection to the jump dis-.

  2. The transition from two phase bubble flow to slug flow

    E-Print Network [OSTI]

    Radovcich, Nick A.

    1962-01-01T23:59:59.000Z

    The process of transition from bubble to slug flow in a vertical pipe has been studied analytically and experimentally. An equation is presented which gives the agglomeration time as a function of void fraction, channel ...

  3. Tunneling and propagation of vacuum bubbles on dynamical backgrounds

    E-Print Network [OSTI]

    Dennis Simon; Julian Adamek; Aleksandar Rakic; Jens C. Niemeyer

    2009-11-19T23:59:59.000Z

    In the context of bubble universes produced by a first-order phase transition with large nucleation rates compared to the inverse dynamical time scale of the parent bubble, we extend the usual analysis to non-vacuum backgrounds. In particular, we provide semi-analytic and numerical results for the modified nucleation rate in FLRW backgrounds, as well as a parameter study of bubble walls propagating into inhomogeneous (LTB) or FLRW spacetimes, both in the thin-wall approximation. We show that in our model, matter in the background often prevents bubbles from successful expansion and forces them to collapse. For cases where they do expand, we give arguments why the effects on the interior spacetime are small for a wide range of reasonable parameters and discuss the limitations of the employed approximations.

  4. Tunneling and propagation of vacuum bubbles on dynamical backgrounds

    E-Print Network [OSTI]

    Simon, Dennis; Rakic, Aleksandar; Niemeyer, Jens C

    2009-01-01T23:59:59.000Z

    In the context of bubble universes produced by a first-order phase transition with large nucleation rates compared to the inverse dynamical time scale of the parent bubble, we extend the usual analysis to non-vacuum backgrounds. In particular, we provide semi-analytic and numerical results for the modified nucleation rate in FLRW backgrounds, as well as a parameter study of bubble walls propagating into inhomogeneous (LTB) or FLRW spacetimes, both in the thin-wall approximation. We show that in our model, matter in the background often prevents bubbles from succesful expansion and forces them to collapse. For cases where they do expand, we give arguments why the effects on the interior spacetime are small for a wide range of reasonable parameters and discuss the limitations of the employed approximations.

  5. Nanoemulsions obtained via bubble bursting at a compound interface

    E-Print Network [OSTI]

    Feng, Jie; Vigolo, Daniele; Arnaudov, Luben N; Stoyanov, Simeon D; Gurkov, Theodor D; Tsutsumanova, Gichka G; Stone, Howard A

    2013-01-01T23:59:59.000Z

    The bursting of bubbles at an air/liquid interface is a familiar occurrence important to foam stability, cell cultures in bioreactors and mass transfer between the sea and atmosphere. Here we document the hitherto unreported formation and dispersal into the water column of submicrometre oil droplets following bubble bursting at a compound air/oil/water-with-surfactant interface. We show that dispersal results from the detachment of an oil spray from the bottom of the bubble towards water during bubble collapse. We provide evidence that droplet size is selected by physicochemical interactions between oil molecules and the surfactants rather than by hydrodynamic effects. We illustrate the unrecognized role that this dispersal mechanism may play in the fate of the sea surface micro-layer and of pollutant spills by dispersing petroleum in the water column. Finally, our system provides an energy-efficient route, with potential upscalability and wide applicability, for applications in drug delivery, food production...

  6. Steam bubble collapse, water hammer and piping network response

    E-Print Network [OSTI]

    Gruel, R.

    Work on steam bubble collapse, water hammer and piping network response was carried out in two closely related but distinct sections. Volume I of ,,is report details the experiments and analyses carried out in conjunction ...

  7. Numerical Simulation of 3D Bubbles Rising in Viscous Liquids using a Front Tracking Method

    E-Print Network [OSTI]

    Lin, Ping

    Hua a , Jan F. Stene b and Ping Lin b a Institute of High Performance Computing, 1 Science Park Road of High Performance Computing 1 Science Park Road, #01-01 The Capricorn Singapore 117528 Email address. Stene b and Ping Lin b a Institute of High Performance Computing, 1 Science Park Road, #01

  8. Single Bubble in Laminar and Turbulent Shear Flows Using Interface Tracking

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9Morgan McCorkleSingin' in the Rain News News

  9. Bubbles as tracers of heat input to cooling flows

    E-Print Network [OSTI]

    J. Binney; F. Alouani Bibi; H. Omma

    2007-01-31T23:59:59.000Z

    We examine the distribution of injected energy in three-dimensional, adaptive-grid simulations of the heating of cooling flows. We show that less than 10 percent of the injected energy goes into bubbles. Consequently, the energy input from the nucleus is underestimated by a factor of order 6 when it is taken to be given by PVgamma/(gamma-1), where P and V are the pressure and volume of the bubble, and gamma the ratio of principal specific heats.

  10. Engineering analyses of large precision cathode strip chambers for GEM

    SciTech Connect (OSTI)

    Horvath, J.A.; Belser, F.C.; Pratuch, S.M.; Wuest, C.R. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Mitselmakher, G. [Superconducting Super Collider Lab., Dallas, TX (United States)] [Superconducting Super Collider Lab., Dallas, TX (United States); Gordeev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation)] [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Johnson, C.V. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); [Superconducting Super Collider Lab., Dallas, TX (United States); Polychronakos, V.A. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States); Golutvin, I.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation)] [Joint Institute for Nuclear Research, Dubna (Russian Federation)

    1993-10-21T23:59:59.000Z

    Structural analyses of large precision cathode strip chambers performed up to the date of this publication are documented. Mechanical property data for typical chamber materials are included. This information, originally intended to be an appendix to the {open_quotes}CSC Structural Design Bible,{close_quotes} is presented as a guide for future designers of large chambers.

  11. Chapter 7.32 Centura-MxP+ Chamber

    E-Print Network [OSTI]

    Healy, Kevin Edward

    P+ is a magnetically enhanced reactive ion etch chamber typically used for etching oxide and nitride patternsChapter 7.32 Centura-MxP+ Chamber (centura-mxp) (586) 1.0 Equipment Purpose 1.1 The Centura Mx in the wafer. 1.2 The Centura platform is a fully automated, multi-wafer capacity, multi-chamber system

  12. Overview of Chamber and Power Plant Designs for IFE

    E-Print Network [OSTI]

    Overview of Chamber and Power Plant Designs for IFE Wayne Meier Deputy Program Leader Fusion Energy power plant are illustrated here Target Factory and Injector Fusion ChamberDriver Power Conversion Review 1/30/11 4 Tritium Processing #12;There have been >50 IFE chamber design concepts and power plant

  13. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    E-Print Network [OSTI]

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-01-01T23:59:59.000Z

    neutralization on heavy-ion fusion chamber transport,” totechniques for heavy ion fusion chamber transport,” Nucl.liquid heavy-ion fusion target chambers,” Fusion Technol.

  14. Bubble formation in water with addition of a hydrophobic solute

    E-Print Network [OSTI]

    Ryuichi Okamoto; Akira Onuki

    2015-05-29T23:59:59.000Z

    We show that phase separation can occur in a one-component liquid outside its coexistence curve (CX) with addition of a small amount of a solute. The solute concentration at the transition decreases with increasing the difference of the solvation chemical potential between liquid and gas. As a typical bubble-forming solute, we consider ${\\rm O}_2$ in ambient liquid water, which exhibits mild hydrophobicity and its critical temperature is lower than that of water. Such a solute can be expelled from the liquid to form gaseous domains while the surrounding liquid pressure is higher than the saturated vapor pressure $p_{cx}$. This solute-induced bubble formation is a first-order transition in bulk and on a partially dried wall, while a gas film grows continuously on a completely dried wall. We set up a bubble free energy $\\Delta G$ for bulk and surface bubbles with a small volume fraction $\\phi$. It becomes a function of the bubble radius $R$ under the Laplace pressure balance. Then, for sufficiently large solute densities above a threshold, $\\Delta G$ exhibits a local maximum at a critical radius and a minimum at an equilibrium radius. We also examine solute-induced nucleation taking place outside CX, where bubbles larger than the critical radius grow until attainment of equilibrium.

  15. Energy Tracking Software Platform

    SciTech Connect (OSTI)

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04T23:59:59.000Z

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  16. Spherically symmetric conformal gravity and "gravitational bubbles"

    E-Print Network [OSTI]

    V. A. Berezin; V. I. Dokuchaev; Yu. N. Eroshenko

    2014-12-09T23:59:59.000Z

    The general structure of the spherically symmetric solutions in the Weyl conformal gravity is described. The corresponding Bach equation are derived for the special type of metrics, which can be considered as the representative of the general class. The complete set of the pure vacuum solutions is found. It consists of two classes. The first one contains the solutions with constant two-dimensional curvature scalar of our specific metrics, and the representatives are the famous Robertson-Walker metrics. One of them we called the "gravitational bubbles", which is compact and with zero Weyl tensor. The second class is more general, with varying curvature scalar. We found its representative as the one-parameter family. It appears that it can be conformally covered by the thee-parameter Mannheim-Kazanas solution. We also investigated the general structure of the energy-momentum tensor in the spherical conformal gravity and constructed the vectorial equation that reveals clearly the same features of non-vacuum solutions. One of them, the metrics a la Vaidya, is explicitly written.

  17. Track 10: Feedback and Improvement

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 10: Feedback and Improvement

  18. MATERIAL TRACKING USING LANMAS

    SciTech Connect (OSTI)

    Armstrong, F.

    2010-06-07T23:59:59.000Z

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  19. The vacuum bubbles in de Sitter background and black hole pair creation

    E-Print Network [OSTI]

    Bum-Hoon Lee; Wonwoo Lee

    2009-10-07T23:59:59.000Z

    We study the possible types of the nucleation of vacuum bubbles. We classify vacuum bubbles in de Sitter background and present some numerical solutions. The thin-wall approximation is employed to obtain the nucleation rate and the radius of vacuum bubbles. With careful analysis we confirm that Parke's formula is also applicable to the large true vacuum bubbles. The nucleation of the false vacuum bubble in de Sitter background is also evaluated. The tunneling process in the potential with degenerate vacua is analyzed as the limiting cases of the large true vacuum bubble and false vacuum bubble. Next, we consider the pair creation of black holes in the background of bubble solutions. We obtain static bubble wall solutions of junction equation with black hole pair. The masses of created black holes are uniquely determined by the cosmological constant and surface tension on the wall. Finally, we obtain the rate of pair creation of black holes.

  20. ATLAS Tracking Event Data Model

    E-Print Network [OSTI]

    Åkesson, P F; Costa, M J; Elsing, M; Fleischmann, S; Gaponenko, A N; Liebig, W; Moyse, E; Salzburger, A; Siebel, M

    2006-01-01T23:59:59.000Z

    In this report the event data model (EDM) relevant for tracking in the ATLAS experiment is presented. The core component of the tracking EDM is a common track object which is suited to describe tracks in the innermost tracking sub-detectors and in the muon detectors in offline as well as online reconstruction. The design of the EDM was driven by a demand for modularity and extensibility while taking into account the different requirements of the clients. The structure of the track object and the representation of the tracking-relevant information are described in detail.

  1. IFE chamber technology testing program in NIF and chamber development test plan

    SciTech Connect (OSTI)

    Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)

    1995-12-31T23:59:59.000Z

    Issues concerning chamber technology testing program in NIF involving: criteria for evaluation/prioritization of experiments, engineering scaling requirements for test article design and material selection and R and D plan prior to NIF testing were addressed in this paper. In order to maximize the benefits of testing program in NIF, the testing in NIF should provide the experimental data relevant to DEMO design choice or to DEMO design predictive capability by utilizing engineering scaling test article designs. Test plans were developed for 2 promising chamber design concepts. Early testing in non-fusion/non-ignition prior to testing in ignition facility serves a critical role in chamber R and D test plans in order to reduce the risks and costs of the more complex experiments in NIF.

  2. 2013 OSU Bill Tracking Summary 7/9/2013 Chamber Bill no.

    E-Print Network [OSTI]

    Escher, Christine

    Bedwell House HCR 12 Designates the wine, beer and bread yeast Saccharomyces cerevisiae to be the official 2106 Identify areas east of Cascades for siting of energy and supporting facilities Huffman Enrolled Energy and Environment; Land Use Passed in House Apr. 29, 54-1 Passed in Senate May 28, 30-0 Signed

  3. A spark chamber for cosmic ray research 

    E-Print Network [OSTI]

    Jelinek, Al Vincent

    1964-01-01T23:59:59.000Z

    chambez *re r- -e evenis, anc to obtain good sta- s s ical data with the prese. . i sysiezz wou'8 require t! e exarina- iion o" severs' '. '. ous" no. pictures. ne effic ency zoz two simu ianeous particles in argon oius alcohol vspour is e timasec.... to be 75I15~ji. The effic ency of the . con-he' ium and the helium-alcohol vapour zillings are 1 igner about 85- 5(i. 3. Spurious Sparking Spurious sparks in the chamber can be attributed to a num- ber of factors. The most probable cause is ions left...

  4. COMPUTED TOMOGRAPHIC RECONSTRUCTION OF BEAM PROFILES WITH A MULTI-WIRE CHAMBER

    E-Print Network [OSTI]

    Alonso, J.R.

    2010-01-01T23:59:59.000Z

    the beam with a small ion chamber. Both of these techniquesstudies of the chamber. A for heav;' ion radiotherapy beam

  5. Exploring GLIMPSE Bubble N107: Multiwavelength Observations and Simulations

    E-Print Network [OSTI]

    Sidorin, Vojtech; Palous, Jan; Wunsch, Richard; Ehlerova, Sona

    2014-01-01T23:59:59.000Z

    Context. Bubble N107 was discovered in the infrared emission of dust in the Galactic Plane observed by the Spitzer Space Telescope (GLIMPSE survey: l ~ 51.0 deg, b ~ 0.1 deg). The bubble represents an example of shell-like structures found all over the Milky Way Galaxy. Aims. We aim to analyse the atomic and molecular components of N107, as well as its radio continuum emission. With the help of numerical simulations, we aim to estimate the bubble age and other parameters which cannot be derived directly from observations. Methods. From the observations of the HI (I-GALFA) and 13CO (GRS) lines we derive the bubble's kinematical distance and masses of the atomic and molecular components. With the algorithm DENDROFIND, we decompose molecular material into individual clumps. From the continuum observations at 1420 MHz (VGPS) and 327 MHz (WSRT), we derive the radio flux density and the spectral index. With the numerical code ring, we simulate the evolution of stellar-blown bubbles similar to N107. Results. The tot...

  6. Plectoneme tip bubbles: Coupled denaturation and writhing in supercoiled DNA

    E-Print Network [OSTI]

    Christian Matek; Thomas E. Ouldridge; Jonathan P. K. Doye; Ard A. Louis

    2014-04-10T23:59:59.000Z

    Biological information is not only stored in the digital chemical sequence of double helical DNA, but is also encoded in the mechanical properties of the DNA strands, which can influence biochemical processes involving its readout. For example, loop formation in the Lac operon can regulate the expression of key genes, and DNA supercoiling is closely correlated to rhythmic circardian gene expression in cyanobacteria. Supercoiling is also important for large scale organisation of the genome in both eukaryotic and prokaryotic cells. DNA can respond to torsional stress by writhing to form looped structures called plectonemes, thus transferring energy stored as twist into energy stored in bending. Denaturation bubbles can also relax torsional stress, with the enthalpic cost of breaking bonds being compensated by their ability to absorb undertwist. Here we predict a novel regime where bubbles form at the tips of plectonemes, and study its properties using coarse-grained simulations. These tip bubbles can occur for both positive and negative supercoiling and greatly reduce plectoneme diffusion by a pinning mechanism. They can cause plectonemes to preferentially localise to AT rich regions, because bubbles more easily form there. The tip-bubble regime occurs for supercoiling densities and forces that are typically encountered for DNA in vivo, and may be exploited for biological control of genomic processes.

  7. Oscillating plasma bubbles. III. Internal electron sources and sinks

    SciTech Connect (OSTI)

    Stenzel, R. L.; Urrutia, J. M. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)

    2012-08-15T23:59:59.000Z

    An internal electron source has been used to neutralize ions injected from an ambient plasma into a spherical grid. The resultant plasma is termed a plasma 'bubble.' When the electron supply from the filament is reduced, the sheath inside the bubble becomes unstable. The plasma potential of the bubble oscillates near but below the ion plasma frequency. Different modes of oscillations have been observed as well as a subharmonic and multiple harmonics. The frequency increases with ion density and decreases with electron density. The peak amplitude occurs for an optimum current and the instability is quenched at large electron densities. The frequency also increases if Langmuir probes inside the bubble draw electrons. Allowing electrons from the ambient plasma to enter, the bubble changes the frequency dependence on grid voltage. It is concluded that the net space charge density in the sheath determines the oscillation frequency. It is suggested that the sheath instability is caused by ion inertia in an oscillating sheath electric field which is created by ion bunching.

  8. Impact of boundaries on velocity profiles in bubble rafts

    E-Print Network [OSTI]

    Yuhong Wang; Kapilanjan Krishan; Michael Dennin

    2006-01-31T23:59:59.000Z

    Under conditions of sufficiently slow flow, foams, colloids, granular matter, and various pastes have been observed to exhibit shear localization, i.e. regions of flow coexisting with regions of solid-like behavior. The details of such shear localization can vary depending on the system being studied. A number of the systems of interest are confined so as to be quasi-two dimensional, and an important issue in these systems is the role of the confining boundaries. For foams, three basic systems have been studied with very different boundary conditions: Hele-Shaw cells (bubbles confined between two solid plates); bubble rafts (a single layer of bubbles freely floating on a surface of water); and confined bubble rafts (bubbles confined between the surface of water below and a glass plate on top). Often, it is assumed that the impact of the boundaries is not significant in the ``quasi-static limit'', i.e. when externally imposed rates of strain are sufficiently smaller than internal kinematic relaxation times. In this paper, we directly test this assumption for rates of strain ranging from $10^{-3}$ to $10^{-2} {\\rm s^{-1}}$. This corresponds to the quoted quasi-static limit in a number of previous experiments. It is found that the top plate dramatically alters both the velocity profile and the distribution of nonlinear rearrangements, even at these slow rates of strain.

  9. Color-based tracking of plasma dust particles

    SciTech Connect (OSTI)

    Villamayor, Michelle Marie S., E-mail: mvillamayor@nip.upd.edu.ph; Soriano, Maricor N.; Ramos, Henry J. [National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines)] [National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines); Kato, Shuichi; Wada, Motoi [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)] [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2014-02-15T23:59:59.000Z

    Color-based tracking to observe agglomeration of deposited particles inside a compact planar magnetron during plasma discharge was done by creating high dynamic range (HDR) images of photos captured by a Pentax K10D digital camera. Carbon erosion and redeposition was also monitored using the technique. The HDR images were subjected to a chromaticity-based constraint discoloration inside the plasma chamber indicating film formation or carbon redeposition. Results show that dust deposition occurs first near the evacuation pumps due to the pressure gradient and then accumulates at the positively charged walls of the chamber. This method can be applied to monitor dust formation during dusty plasma experiments without major modification of plasma devices, useful especially for large fusion reactors.

  10. ENGINEERING DEVELOPMENT OF SLURRY BUBBLE COLUMN REACTOR (SBCR) TECHNOLOGY

    SciTech Connect (OSTI)

    Bernard A. Toseland, Ph.D.

    1999-03-01T23:59:59.000Z

    The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors. The past three months of research have been focused on two major areas of bubble column hydrodynamics: (1) pressure and temperature effects on gas holdup and (2) region transition using a sparger as a gas distributor.

  11. Electron bubbles in liquid helium: infrared-absorption spectrum

    E-Print Network [OSTI]

    Víctor Grau; Manuel Barranco; Ricardo Mayol; Martí Pi

    2006-01-20T23:59:59.000Z

    Within Density Functional Theory, we have calculated the energy of the transitions from the ground state to the first two excited states in the electron bubbles in liquid helium at pressures from zero to about the solidification pressure. For $^4$He at low temperatures, our results are in very good agreement with infrared absorption experiments. Above a temperature of $\\sim 2$ K, we overestimate the energy of the $1s-1p$ transition. We attribute this to the break down of the Franck-Condon principle due to the presence of helium vapor inside the bubble. Our results indicate that the $1s-2p$ transition energies are sensitive not only to the size of the electron bubble, but also to its surface thickness. We also present results for the infrared transitions in the case of liquid $^3$He, for which we lack of experimental data.

  12. A steerable UV laser system for the calibration of liquid argon time projection chambers

    E-Print Network [OSTI]

    A. Ereditato; I. Kreslo; M. Lüthi; C. Rudolf von Rohr; M. Schenk; T. Strauss; M. Weber; M. Zeller

    2014-10-04T23:59:59.000Z

    A number of liquid argon time projection chambers (LAr TPC's) are being build or are proposed for neutrino experiments on long- and short baseline beams. For these detectors a distortion in the drift field due to geometrical or physics reasons can affect the reconstruction of the events. Depending on the TPC geometry and electric drift field intensity this distortion could be of the same magnitude as the drift field itself. Recently, we presented a method to calibrate the drift field and correct for these possible distortions. While straight cosmic ray muon tracks could be used for calibration, multiple coulomb scattering and momentum uncertainties allow only a limited resolution. A UV laser instead can create straight ionization tracks in liquid argon, and allows one to map the drift field along different paths in the TPC inner volume. Here we present a UV laser feed-through design with a steerable UV mirror immersed in liquid argon that can point the laser beam at many locations through the TPC. The straight ionization paths are sensitive to drift field distortions, a fit of these distortion to the linear optical path allows to extract the drift field, by using these laser tracks along the whole TPC volume one can obtain a 3D drift field map. The UV laser feed-through assembly is a prototype of the system that will be used for the MicroBooNE experiment at the Fermi National Accelerator Laboratory (FNAL).

  13. Automated micro-tracking planar solar concentrators

    E-Print Network [OSTI]

    Hallas, Justin Matthew

    2011-01-01T23:59:59.000Z

    E. Ford, “Reactive self-tracking solar concentration: designFord, “Reactive self- tracking solar concentration: designAutomated Micro-Tracking Planar Solar Concentrators by

  14. Pollution Prevention Tracking and Reporting System | Department...

    Energy Savers [EERE]

    Pollution Prevention Tracking and Reporting System Pollution Prevention Tracking and Reporting System Welcome to the Department of Energy's Pollution Prevention Tracking and...

  15. Interaction of a spark-generated bubble with a rubber beam: Numerical and experimental study

    E-Print Network [OSTI]

    Gong, S. W.

    In this paper, the physical behaviors of the interaction between a spark-generated bubble and a rubber beam are studied. Both numerical and experimental approaches are employed to investigate the bubble collapse near the ...

  16. Numerical simulation of bubble rising in viscous liquid Jinsong Hua *, Jing Lou

    E-Print Network [OSTI]

    Frey, Pascal

    natural and industrial processes such as combustion/ chemical reaction, petroleum refining and boiling, ranging from the rise of steam bubble in boiler tubes to gas bubbles in oil well. However, a comprehensive

  17. Measurements of Heat Transfer Coefficients to Cylinders in Shallow Bubble Columns

    E-Print Network [OSTI]

    Tow, Emily W.

    High heat transfer coefficients and large interfacial areas make bubble columns ideal for dehumidification. However, the effect of geometry on the heat transfer coefficients outside cooling coils in shallow bubble columns, ...

  18. Heat and mass transfer in bubble column dehumidifiers for HDH desalination

    E-Print Network [OSTI]

    Tow, Emily W

    2014-01-01T23:59:59.000Z

    Heat and mass transfer processes governing the performance of bubble dehumidifier trays are studied in order to develop a predictive model and design rules for efficient and economical design of bubble column dehumidifiers ...

  19. Electrochemical investigations of stable cavitation from bubbles generated during reduction of water

    E-Print Network [OSTI]

    Deymier, Pierre

    Electrochemical investigations of stable cavitation from bubbles generated during reduction April 2014 Keywords: Megasonic cleaning Stable cavitation Microstreaming Hydrogen bubbles Water on wafers without affect- ing the transient cavitation responsible for feature damage. Ã? 2014 Elsevier B

  20. Radiative Decay of Bubble Oscillations in a Compressible Fluid

    E-Print Network [OSTI]

    A. M. Shapiro; M. I. Weinstein

    2011-01-01T23:59:59.000Z

    Consider the dynamics of a gas bubble in an inviscid, compressible liquid with surface tension. Kinematic and dynamic boundary conditions couple the bubble surface deformation dynamics with the dynamics of waves in the fluid. This system has a spherical equilibrium state, resulting from the balance of the pressure at infinity and the gas pressure within the bubble. We study the linearized dynamics about this equilibrium state in a center of mass frame: 1) We prove that the velocity potential and bubble surface perturbation satisfy point-wise in space exponential time-decay estimates. 2) The time-decay rate is governed by scattering resonances, eigenvalues of a non-selfadjoint spectral problem. These are pole singularities in the lower half plane of the analytic continuation of a resolvent operator from the upper half plane, across the real axis into the lower half plane. 3) The time-decay estimates are a consequence of resonance mode expansions for the velocity potential and bubble surface perturbations. 4) For small compressibility (Mach number, a ratio of bubble wall velocity to sound speed, \\epsilon), this is a singular perturbation of the incompressible limit. The scattering resonances which govern the anomalously slow time-decay, are {\\it Rayleigh resonances}. Asymptotics, supported by high-precision numerical studies, indicate that the Rayleigh resonances which are closest to the real axis satisfy | \\frac{\\Im \\lambda_\\star(\\epsilon)}{\\Re \\lambda_\\star(\\epsilon)} | = {\\cal O} (\\exp(-\\kappa\\ \\We\\ \\epsilon^{-2})), \\kappa>0. Here, \\We denotes the Weber number, a dimensionless ratio comparing inertia and surface tension. 5) To obtain the above results we prove a general result, of independent interest, estimating the Neumann to Dirichlet map for the wave equation, exterior to a sphere.

  1. How important are shock waves to single-bubble sonoluminescence? H. Y. Cheng,1

    E-Print Network [OSTI]

    Yuan, Li

    at the center of the bubble could be high enough to ignite thermonuclear fusion 3 . Previous calculations based

  2. Formation of seep bubble plumes in the Coal Oil Point seep field

    E-Print Network [OSTI]

    Leifer, Ira; Culling, Daniel

    2010-01-01T23:59:59.000Z

    the gas flux from shallow gas hydrate deposits: interactionupper water column by gas hydrate-coated methane bubbles.

  3. Dielectric liquid ionization chambers for detecting fast neutrons

    E-Print Network [OSTI]

    Boyd, Erin M

    2008-01-01T23:59:59.000Z

    Three ionization chambers with different geometries have been constructed and filled with dielectric liquids for detection of fast neutrons. The three dielectric liquids studied were Tetramethylsilane (TMS), Tetramethylpentane ...

  4. air wall ionization chambers: Topics by E-print Network

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

    of California eScholarship Repository Summary: chamber, passive sampling, passive solar house, measurementhouse, we planed the distribution of fresh air, passivepassive...

  5. Second United Nations International Conference

    Office of Scientific and Technical Information (OSTI)

    Second United Nations International Conference on the Peaceful Uses of Atomic Energy ON THE ANALYSIS O F BUBBLE CHAMBER TRACKS Q Hugh Bradner and F r a n k Solmitz INTRODUCTION A j...

  6. Mechanism of mass transfer between a bubble initially composed of oxygen and molten glass1

    E-Print Network [OSTI]

    Boyer, Edmond

    Mechanism of mass transfer between a bubble initially composed of oxygen and molten glass1 F ­ BP 135, 93303 Aubervilliers Cedex, France Abstract The bubble removal from molten glass is an important problem in glass melting process. In this paper, the mass transfer undergone by a bubble rising

  7. A MICROSTRUCTURED CATHODE FOR FUEL CELL WITH SELF-REGULATED O2 BUBBLE CREATION AND CONSUMPTION

    E-Print Network [OSTI]

    pumping mechanism [1]. In the bubble pumping mechanism, carbon dioxide generated inside the anodic channel forms bubbles that fill the channel and directionally grow away from the check valve. The carbon dioxideA MICROSTRUCTURED CATHODE FOR FUEL CELL WITH SELF-REGULATED O2 BUBBLE CREATION AND CONSUMPTION

  8. Dissolution of carbon dioxide bubbles and microfluidic multiphase flows Ruopeng Sun and Thomas Cubaud*

    E-Print Network [OSTI]

    Cubaud, Thomas

    Dissolution of carbon dioxide bubbles and microfluidic multiphase flows Ruopeng Sun and Thomas the dissolution of carbon dioxide bubbles into common liquids (water, ethanol, and methanol) using microfluidic devices. Elongated bubbles are individually produced using a hydrodynamic focusing section into a compact

  9. Correlation of black oil properties at pressures below the bubble-point

    E-Print Network [OSTI]

    Velarde, Jorge Javier

    1996-01-01T23:59:59.000Z

    correlations: Bubble-point pressure, Pb *Solution gas-oil-ratio at pressures below the bubble-point, Rs ³Oil formation volume factor at pressures below the bubble-point, B0 In this work we provide a detailed analysis of the most popular correlations...

  10. Viscosity of magmas containing highly deformable bubbles M. Mangaa,*, M. Loewenbergb

    E-Print Network [OSTI]

    Manga, Michael

    Viscosity of magmas containing highly deformable bubbles M. Mangaa,*, M. Loewenbergb a Department The shear viscosity of a suspension of deformable bubbles dispersed within a Newtonian ¯uid is calculated. For small Ca, bubbles remain nearly spherical, and for suf®ciently large strains the viscosity of suspension

  11. Birth and Growth of Cavitation Bubbles within Water under Tension Confined in a Simple Synthetic Tree

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Birth and Growth of Cavitation Bubbles within Water under Tension Confined in a Simple Synthetic. Cavitation can spontaneously occur, nucleating a bubble. We investigate the dynamics of spontaneous or triggered cavitation inside water filled microcavities of a hydrogel. Results show that a stable bubble

  12. acoustic cavitation of slightly subcritical bubbles of Mathematics, Boston University, Boston, Massachusetts 02215

    E-Print Network [OSTI]

    Harkin, Anthony

    On acoustic cavitation of slightly subcritical bubbles Anthony ¡ Harkin Department Blake threshold indicates the onset of quasistatic evolution leading to cavitation for gas§ bubbles would cavitate. In this work, we analyze the cavitation threshold for radially symmetric bubbles whose

  13. Molecular and atomic emission during single-bubble cavitation in concentrated sulfuric acid

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Molecular and atomic emission during single- bubble cavitation in concentrated sulfuric acid David during cavitation. Single-bubble sonoluminescence (SBSL) from sulfuric acid (H2SO4) is much brighter than occurring during single- bubble cavitation. In fact, SBSL spectra from organic liquids8,9 have been

  14. MODELING SPACE-TIME DEPENDENT HELIUM BUBBLE EVOLUTION IN TUNGSTEN ARMOR UNDER IFE CONDITIONS

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    MODELING SPACE-TIME DEPENDENT HELIUM BUBBLE EVOLUTION IN TUNGSTEN ARMOR UNDER IFE CONDITIONS Qiyang dependent Helium transport in finite geometries, including the simultaneous transient production of defects of Helium bubbles. I. INTRODUCTION Helium production and helium bubble evolution in neutron

  15. Nuclear Instruments and Methods in Physics Research A 491 (2002) 470473 Experimental study of track density distribution on

    E-Print Network [OSTI]

    Yu, K.N.

    with a filter paper on the top. While radon progeny are stopped by the filter, radon gas is free to diffuse the radial distribution of track density will depend on the partitioning between the radon progeny in the air volume and those on the inner surfaces of the diffusion chamber. The first radon progeny 218 Po has

  16. Forward Drift Chamber for the GlueX Experiment at the 12 GeV CEBAF Machine

    SciTech Connect (OSTI)

    Pentchev, Lubomir; Zihlmann, Benedikt [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA 23606 (United States)

    2011-06-01T23:59:59.000Z

    The GlueX experiment will search for exotic mesons produced by 9 GeV linearly polarized photons from the upgraded CEBAF machine. It is critical to detect and measure the four-momenta of all the charged particles and photons resulting from the decays of the mesons. The solenoid-based detector system includes tracking detectors and calorimeters. The Forward Drift Chamber, FDC, consists of 24 circular planar drift chambers of 1m diameter. Additional cathode readout is required to achieve efficient pattern recognition. The detection of photons by the electromagnetic calorimeters imposes constraints on the amount of material used in the FDC. The specific features of the detector and the readout electronics will be described. Results from the tests of the full scale prototype will be presented, as well.

  17. Forward Drift Chamber for the GlueX experiment at the 12 GeV CEBAF machine

    SciTech Connect (OSTI)

    Lubomir Pentchev, Benedikt Zihlmann

    2011-06-01T23:59:59.000Z

    The GlueX experiment will search for exotic mesons produced by 9 GeV linearly polarized photons from the upgraded CEBAF machine. It is critical to detect and measure the four-momenta of all the charged particles and photons resulting from the decays of the mesons. The solenoid-based detector system includes tracking detectors and calorimeters. The Forward Drift Chamber, FDC, consists of 24 circular planar drift chambers of 1m diameter. Additional cathode readout is required to achieve efficient pattern recognition. The detection of low energy photons by the electromagnetic calorimeters imposes constraints on the amount of material used in the FDC. The specific features of the detector and the readout electronics will be described. Results from the tests of the full scale prototype will be presented, as well.

  18. Radiopurity assessment of the tracking readout for the NEXT double beta decay experiment

    E-Print Network [OSTI]

    Álvarez, V; Barrado, A I; Bettini, A; Borges, F I G M; Camargo, M; Cárcel, S; Cebrián, S; Cervera, A; Conde, C A N; Conde, E; Dafni, T; Díaz, J; Esteve, R; Fernandes, L M P; Fernández, M; Ferrario, P; Ferreira, A L; Freitas, E D C; Gehman, V M; Goldschmidt, A; Gómez, H; Gómez-Cadenas, J J; González-Díaz, D; Gutiérrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Iguaz, F J; Irastorza, I G; Labarga, L; Laing, A; Liubarsky, I; Lorca, D; Losada, M; Luzón, G; Marí, A; Martín-Albo, J; Martínez, A; Martínez-Lema, G; Miller, T; Monrabal, F; Monserrate, M; Monteiro, C M B; Mora, F J; Moutinho, L M; Vidal, J Muñoz; Nebot-Guinot, M; Nygren, D; Oliveira, C A B; de Solórzano, A Ortiz; Pérez, J; Aparicio, J L Pérez; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Segui, L; Serra, L; Shuman, D; Simón, A; Sofka, C; Sorel, M; Toledo, J F; Torrent, J; Tsamalaidze, Z; Veloso, J F C A; Villar, J A; Webb, R C; White, J T; Yahlali, N

    2014-01-01T23:59:59.000Z

    The 'Neutrino Experiment with a Xenon Time-Projection Chamber' (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds; therefore, an extensive screening and selection process is underway to control the radiopurity levels of the materials to be used in the experimental set-up of NEXT. The detector design combines the measurement of the topological signature of the event for background discrimination with the energy resolution optimization. Separate energy and tracking readout planes are based on different sensors: photomultiplier tubes for calorimetry and silicon multi-pixel photon counters for tracking. The design of a radiopure tracking plane, in direct contact with the gas detector medium, was a challenge since the needed components have typically activities too large for experiments requiring ultra-low background conditions. Here, the radiopurity assessment of tracking readout components based on gamma-ray spectroscopy usi...

  19. Incorporation of Reaction Kinetics into a Multiphase, Hydrodynamic Model of a Fischer Tropsch Slurry Bubble Column Reactor

    SciTech Connect (OSTI)

    Donna Guillen, PhD; Anastasia Gribik; Daniel Ginosar, PhD; Steven P. Antal, PhD

    2008-11-01T23:59:59.000Z

    This paper describes the development of a computational multiphase fluid dynamics (CMFD) model of the Fischer Tropsch (FT) process in a Slurry Bubble Column Reactor (SBCR). The CMFD model is fundamentally based which allows it to be applied to different industrial processes and reactor geometries. The NPHASE CMFD solver [1] is used as the robust computational platform. Results from the CMFD model include gas distribution, species concentration profiles, and local temperatures within the SBCR. This type of model can provide valuable information for process design, operations and troubleshooting of FT plants. An ensemble-averaged, turbulent, multi-fluid solution algorithm for the multiphase, reacting flow with heat transfer was employed. Mechanistic models applicable to churn turbulent flow have been developed to provide a fundamentally based closure set for the equations. In this four-field model formulation, two of the fields are used to track the gas phase (i.e., small spherical and large slug/cap bubbles), and the other two fields are used for the liquid and catalyst particles. Reaction kinetics for a cobalt catalyst is based upon values reported in the published literature. An initial, reaction kinetics model has been developed and exercised to demonstrate viability of the overall solution scheme. The model will continue to be developed with improved physics added in stages.

  20. Visualization and simulation of bubble growth in pore networks

    SciTech Connect (OSTI)

    Li, Xuehai; Yortsos, Y.C.

    1994-03-01T23:59:59.000Z

    Bubble nucleation and bubble growth in porous media is an important problem encountered in processes, such as pressure depletion and boiling. To understand its basic aspects, experiments and numerical simulations in micromodel geometries were undertaken. Experiments of bubble growth by pressure depletion were carried out in 2-D etched-glass micromodels and in Hele-Shaw cells. Nucleation of bubbles and the subsequent growth of gas clusters were visualized. Contrary to the bulk or to Hele-Shaw cells, gas clusters in the micromodel have irregular and ramified shapes and share many of the features of an external invasion process (e.g. of percolation during drainage). A pore network numerical model was developed to simulate the growth of multiple gas clusters under various conditions. The model is based on the solution of the convection-diffusions equation and also accounts for capillary and viscous forces, which play an important role in determining the growth patterns. Numerical simulation resulted in good agreement with the experimental results.

  1. Nickel Bubble Expansion in Type Ia Supernovae: Adiabatic Solutions

    E-Print Network [OSTI]

    Chih-Yueh Wang

    2008-06-20T23:59:59.000Z

    This paper presents hydrodynamical and radiation-hydrodynamical simulations of the nickel bubble effect in Type Ia supernovae, comparison of results to self-similar solutions, and application to observations of Type Ia supernova remnants, with a particular emphasis on Tycho's SNR.

  2. The oil price really is a speculative bubble

    E-Print Network [OSTI]

    Eckaus, Richard S.

    2008-01-01T23:59:59.000Z

    The oil price really is a speculative bubble. Yet only recently has the U.S. Congress, for example, showed recognition that this might even be a possibility. In general there seems to be a preference for the claim that the ...

  3. Mobius Transformations, Power Diagrams, Lombardi Drawings, and Soap Bubbles

    E-Print Network [OSTI]

    Eppstein, David

    M¨obius Transformations, Power Diagrams, Lombardi Drawings, and Soap Bubbles David Eppstein Euro a novel type of power diagram for disks in the plane that is invariant under M¨obius transformations Using For points outside circle, power = (positive) length of tangent segment For points inside circle, power = -1

  4. An analytic description of thick-wall bubbles

    SciTech Connect (OSTI)

    Hong, Jooyoo

    1992-08-01T23:59:59.000Z

    A new approximation scheme to the false-vacuum decay is suggested. In this scheme the bounce solutions can be obtained in an explicit and analytic way even for thick-wall bubbles. The result is compared with Coleman`s thin-wall description, which shows that is nicely comprises the result of the latter prescription. Some applications are also discussed.

  5. 6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines | Science 5 Senses 1/4...globalproductivityforum.info/.../the-use-of-acoustic-inversion-to-estimate-the-bubble-size-distribu...

    E-Print Network [OSTI]

    Sóbester, András

    6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines method to more accurately measure gas bubbles in pipelines. The ability to measure gas bubbles in 2010. Currently, the most popular technique for estimating the gas bubble size distribution (BSD

  6. Mechanics of Bubbles in Sludges and Slurries Modeling Studies of Particulate Materials

    SciTech Connect (OSTI)

    Phillip A. Gauglitz; Guillermo Terrones; Susan J. Muller; Morton M. Denn; William R. Rossen

    2002-01-07T23:59:59.000Z

    The Hanford Site has 177 underground waste storage tanks that are known to retain and release bubbles composed of flammable gases. Characterizing and understanding the behavior of these bubbles is important for the safety issues associated with the flammable gases for both ongoing waste storage and future waste-retrieval operations. The retained bubbles are known to respond to small barometric pressure changes, though in a complex manner with unusual hysteresis occurring in some tanks in the relationship between bubble volume and pressure, or V-P hysteresis. With careful analysis, information on the volume of retained gas and the interactions of the waste and the bubbles can be determined.

  7. Exciting Internship at the American Arab Chamber of Commerce

    E-Print Network [OSTI]

    Cinabro, David

    Exciting Internship at the American Arab Chamber of Commerce Take advantage of the opportunity@americanarab.com with the subject "Internship Opportunity." Include a brief statement on why you would like to work at the American Arab Chamber of Commerce, along with your availability. If you are looking for an internship to fulfill

  8. aerosol test chamber: Topics by E-print Network

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

    aerosol test chamber First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 IFE Chamber Technology Testing...

  9. Oscillating plasma bubbles. IV. Grids, geometry, and gradients

    SciTech Connect (OSTI)

    Stenzel, R. L. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States); Urrutia, J. M. [Urrutia Scientific, Van Nuys, California 91406 (United States)

    2012-08-15T23:59:59.000Z

    Plasma bubbles are created in an ambient plasma. The bubble is formed inside a cavity bounded by a negatively biased grid. Ions are injected through the grid and neutralized by electrons from either the background plasma or an internal electron emitter. The external electron supply is controlled by the grid bias relative to the external plasma potential. When the electron flux is restricted to the ion flux, the sheath of the bubble becomes unstable and causes the plasma potential to oscillate near the ion plasma frequency. The exact frequency depends on the net space charge density in the bubble sheath. The frequency increases with density and grid voltage, provided the grid forms a parallel equipotential surface. The present investigation shows that when the Debye length becomes smaller than the grid openings the electron flux cannot be controlled by the grid voltage. The frequency dependence on grid voltage and density is modified creating frequency and amplitude jumps. Low frequency sheath oscillations modulate the high frequency normal oscillations. Harmonics and subharmonics are excited by electrons in an ion-rich sheath. When the plasma parameters vary over the bubble surface, the sheath may oscillate at different frequencies. A cavity with two isolated grids has been used to investigate anisotropies of the energetic electron flux in a discharge plasma. The frequency dependence on grid voltage is entirely different when the grid controls the energetic electrons or the bulk electrons. These observations are important to several fields of basic plasma physics, such as sheaths, sheath instabilities, diagnostic probes, current, and space charge neutralization of ion beams.

  10. LED Price Tracking Form

    Broader source: Energy.gov [DOE]

    DOE intends to update the SSL Pricing and Efficacy Trend Analysis for Utility Program Planning report on an annual basis, but doing so requires that we have sufficient product and purchase data including acquisition date, purchase price, product category, and rated initial lumens. Those interested in helping collect this data are asked to use the LED Price Tracking FormMicrosoft Excel and follow the instructions for submitting data.

  11. EFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE Zoran Dragojlovic1

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    -rays and ions travel through the chamber and deposit some of their energy in the chamber background gas; the effects of various heat sources and transfer mechanisms such as photon and ion heat deposition and chamberEFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE CHAMBERS Zoran

  12. Vacuum chamber for ion manipulation device

    DOE Patents [OSTI]

    Chen, Tsung-Chi; Tang, Keqi; Ibrahim, Yehia M; Smith, Richard D; Anderson, Gordon A; Baker, Erin M

    2014-12-09T23:59:59.000Z

    An ion manipulation method and device is disclosed. The device includes a pair of substantially parallel surfaces. An array of inner electrodes is contained within, and extends substantially along the length of, each parallel surface. The device includes a first outer array of electrodes and a second outer array of electrodes. Each outer array of electrodes is positioned on either side of the inner electrodes, and is contained within and extends substantially along the length of each parallel surface. A DC voltage is applied to the first and second outer array of electrodes. A RF voltage, with a superimposed electric field, is applied to the inner electrodes by applying the DC voltages to each electrode. Ions either move between the parallel surfaces within an ion confinement area or along paths in the direction of the electric field, or can be trapped in the ion confinement area. A predetermined number of pairs of surfaces are disposed in one or more chambers, forming a multiple-layer ion mobility cyclotron device.

  13. Review of Particle Physics

    E-Print Network [OSTI]

    Nakamura, Kenzo

    2010-01-01T23:59:59.000Z

    in liquid (bubble chamber) hydrogen, gaseous helium, carbon,liquid (bubble chamber) hydrogen, helium gas, carbon, iron,

  14. Particle Physics Booklet 2008

    E-Print Network [OSTI]

    et al., C. Amsler

    2008-01-01T23:59:59.000Z

    in liquid (bubble chamber) hydrogen, gaseous helium, carbon,liquid (bubble chamber) hydrogen, helium gas, carbon, iron,

  15. REVIEW OF PARTICLE PHYSICS

    E-Print Network [OSTI]

    Beringer, Juerg

    2013-01-01T23:59:59.000Z

    liquid (bubble chamber) hydrogen, helium gas, carbon, iron,in liquid (bubble chamber) hydrogen, gaseous helium, carbon,

  16. May 31-June 1, 2001 A. R. Raffray, et al., Assessment of Dry Chamber Walls as Preliminary Step in Defining Key Processes for Chamber Clearing Code 1

    E-Print Network [OSTI]

    Raffray, A. René

    in Defining Key Processes for Chamber Clearing Code 6 Photon and Ion Attenuations in Carbon and Tungsten #12May 31-June 1, 2001 A. R. Raffray, et al., Assessment of Dry Chamber Walls as Preliminary Step in Defining Key Processes for Chamber Clearing Code 1 Assessment of Dry Chamber Wall Configurations

  17. Variation of calibration constant of alpha track detectors with respect to altitude 

    E-Print Network [OSTI]

    Vasudevan, Latha

    1991-01-01T23:59:59.000Z

    solutions, has been found useful in determining the degree of etch. The study reported here is not only limited to finding out the calibration constant of LR 115 II films at ambient atmospheric pressure, but also under various air pressure conditions... Chamber Detector System Lucas Cell Efficiency Calibration of the Lucas Cell Etching Bath Etching Vial Image Processing System Calibration of the Optical System 24 24 25 26 27 30 34 35 36 36 Particle Track Counting Spectrophotometry...

  18. Turbine component cooling channel mesh with intersection chambers

    DOE Patents [OSTI]

    Lee, Ching-Pang; Marra, John J

    2014-05-06T23:59:59.000Z

    A mesh (35) of cooling channels (35A, 35B) with an array of cooling channel intersections (42) in a wall (21, 22) of a turbine component. A mixing chamber (42A-C) at each intersection is wider (W1, W2)) than a width (W) of each of the cooling channels connected to the mixing chamber. The mixing chamber promotes swirl, and slows the coolant for more efficient and uniform cooling. A series of cooling meshes (M1, M2) may be separated by mixing manifolds (44), which may have film cooling holes (46) and/or coolant refresher holes (48).

  19. IMAGING WITH A MULTIPLANE MULTIWIRE PROPORTIONAL CHAMBER USING HEAVY ION BEAMS

    E-Print Network [OSTI]

    Chu, W.T.

    2010-01-01T23:59:59.000Z

    1. When the he^vy ions penetrate the chamber, the resultingMULTIWIRE PROPORTIONAL CHAMBER USING HEAVY-ION BEAMS* U. T.Ion Beam Studies and Imaging with a Nultiplane Multiwire Proportional Chamber,"

  20. THE MILKY WAY PROJECT: LEVERAGING CITIZEN SCIENCE AND MACHINE LEARNING TO DETECT INTERSTELLAR BUBBLES

    SciTech Connect (OSTI)

    Beaumont, Christopher N.; Williams, Jonathan P. [Institute for Astronomy, University of Hawai'i, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Goodman, Alyssa A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Kendrew, Sarah; Simpson, Robert, E-mail: beaumont@ifa.hawaii.edu [Department of Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)

    2014-09-01T23:59:59.000Z

    We present Brut, an algorithm to identify bubbles in infrared images of the Galactic midplane. Brut is based on the Random Forest algorithm, and uses bubbles identified by >35,000 citizen scientists from the Milky Way Project to discover the identifying characteristics of bubbles in images from the Spitzer Space Telescope. We demonstrate that Brut's ability to identify bubbles is comparable to expert astronomers. We use Brut to re-assess the bubbles in the Milky Way Project catalog, and find that 10%-30% of the objects in this catalog are non-bubble interlopers. Relative to these interlopers, high-reliability bubbles are more confined to the mid-plane, and display a stronger excess of young stellar objects along and within bubble rims. Furthermore, Brut is able to discover bubbles missed by previous searches—particularly bubbles near bright sources which have low contrast relative to their surroundings. Brut demonstrates the synergies that exist between citizen scientists, professional scientists, and machine learning techniques. In cases where ''untrained' citizens can identify patterns that machines cannot detect without training, machine learning algorithms like Brut can use the output of citizen science projects as input training sets, offering tremendous opportunities to speed the pace of scientific discovery. A hybrid model of machine learning combined with crowdsourced training data from citizen scientists can not only classify large quantities of data, but also address the weakness of each approach if deployed alone.

  1. Compression-induced stacking fault tetrahedra around He bubbles in Al

    SciTech Connect (OSTI)

    Shao, Jian-Li, E-mail: shao-jianli@iapcm.ac.cn; Wang, Pei; He, An-Min [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)

    2014-10-28T23:59:59.000Z

    Classic molecular dynamics methods are used to simulate the uniform compression process of the fcc Al containing He bubbles. The formation of stacking fault tetrahedra (SFTs) during the collapse of He bubbles is found, and their dependence on the initial He bubble size (0.6–6?nm in diameter) is presented. Our simulations indicate only elastic deformation in the samples for the He bubble size not more than 2?nm. Instead, increasing the He bubble size, we detect several small SFTs forming on the surface of the He bubble (3?nm), as well as the two intercrossed SFTs around the He bubbles (4–6?nm). All these SFTs are observed to be stable under further compression, though there may appear some SF networks outside the SFTs (5–6?nm). Furthermore, the dynamic analysis on the SFTs shows that the yield pressure keeps a near-linear increase with the initial He bubble pressure, and the potential energy of Al atoms inside the SFTs is lower than outside because of their gliding inwards. In addition, the pressure increments of 2–6?nm He bubbles with strain are less than that of Al, which just provides the opportunity for the He bubble collapse and the SFTs formation. Note that the current work only focuses on the case that the number ratio between He atoms and Al vacancies is 1:1.

  2. Data Reduction Processes Using FPGA for MicroBooNE Liquid Argon Time Projection Chamber

    SciTech Connect (OSTI)

    Wu, Jinyuan

    2010-05-26T23:59:59.000Z

    MicroBooNE is a liquid Argon time projection chamber to be built at Fermilab for an accelerator-based neutrino physics experiment and as part of the R&D strategy for a large liquid argon detector at DUSEL. The waveforms of the {approx}9000 sense wires in the chamber are continuously digitized at 2 M samples/s - which results in a large volume of data coming off the TPC. We have developed a lossless data reduction scheme based on Huffman Coding and have tested the scheme on cosmic ray data taken from a small liquid Argon time projection chamber, the BO detector. For sense wire waveforms produced by cosmic ray tracks, the Huffman Coding scheme compresses the data by a factor of approximately 10. The compressed data can be fully recovered back to the original data since the compression is lossless. In addition to accelerator neutrino data, which comes with small duty cycle in sync with the accelerator beam spill, continuous digitized waveforms are to be temporarily stored in the MicroBooNE data-acquisition system for about an hour, long enough for an external alert from possible supernova events. Another scheme, Dynamic Decimation, has been developed to compress further the potential supernova data so that the storage can be implemented within a reasonable budget. In the Dynamic Decimation scheme, data are sampled at the full sampling rate in the regions-of-interest (ROI) containing waveforms of track-hits and are decimated down to lower sampling rate outside the ROI. Note that unlike in typical zerosuppression schemes, in Dynamic Decimation, the data in the pedestal region are not thrown away but kept at a lower sampling rate. An additional factor of 10 compression ratio is achieved using the Dynamic Decimation scheme on the BO detector data, making a total compression rate of approximate 100 when the Dynamic Decimation and the Huffman Coding functional blocks are cascaded. Both of the blocks are compiled in low-cost FPGA and their silicon resource usages are low.

  3. ENGINEERING DEVELOPMENT OF SLURRY BUBBLE COLUMN REACTOR (SBCR) TECHNOLOGY

    SciTech Connect (OSTI)

    Bernard A. Toseland

    2002-09-30T23:59:59.000Z

    The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors.

  4. ENGINEERING DEVELOPMENT OF SLURRY BUBBLE COLUMN REACTOR (SBCR) TECHNOLOGY

    SciTech Connect (OSTI)

    Bernard A. Toseland, Ph.D.

    2000-06-01T23:59:59.000Z

    The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column 0reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors.

  5. Engineering Development of Slurry Bubble Column Reactor (SBCR) Technology

    SciTech Connect (OSTI)

    Toseland, B.A.

    1998-10-29T23:59:59.000Z

    The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors.

  6. Dynamics of false vacuum bubbles: beyond the thin shell approximation

    E-Print Network [OSTI]

    Jakob Hansen; Dong-il Hwang; Dong-han Yeom

    2009-11-08T23:59:59.000Z

    We numerically study the dynamics of false vacuum bubbles which are inside an almost flat background; we assumed spherical symmetry and the size of the bubble is smaller than the size of the background horizon. According to the thin shell approximation and the null energy condition, if the bubble is outside of a Schwarzschild black hole, unless we assume Farhi-Guth-Guven tunneling, expanding and inflating solutions are impossible. In this paper, we extend our method to beyond the thin shell approximation: we include the dynamics of fields and assume that the transition layer between a true vacuum and a false vacuum has non-zero thickness. If a shell has sufficiently low energy, as expected from the thin shell approximation, it collapses (Type 1). However, if the shell has sufficiently large energy, it tends to expand. Here, via the field dynamics, field values of inside of the shell slowly roll down to the true vacuum and hence the shell does not inflate (Type 2). If we add sufficient exotic matters to regularize the curvature near the shell, inflation may be possible without assuming Farhi-Guth-Guven tunneling. In this case, a wormhole is dynamically generated around the shell (Type 3). By tuning our simulation parameters, we could find transitions between Type 1 and Type 2, as well as between Type 2 and Type 3. Between Type 2 and Type 3, we could find another class of solutions (Type 4). Finally, we discuss the generation of a bubble universe and the violation of unitarity. We conclude that the existence of a certain combination of exotic matter fields violates unitarity.

  7. Environmental chamber studies of atmospheric reactivities of volatile organic compounds: Effects of varying chamber and light source

    SciTech Connect (OSTI)

    Carter, W.; Luo, D.; Malkina, I.; Pierce, J. [California Univ., Riverside, CA (United States)

    1995-05-01T23:59:59.000Z

    Photochemical oxidant models are essential tools for assessing effects of emissions changes on ground-level ozone formation. Such models are needed for predicting the ozone impacts of increased alternative fuel use. The gas-phase photochemical mechanism is an important component of these models because ozone is not emitted directly, but is formed from the gas-phase photochemical reactions of the emitted volatile organic compounds (VOCs) and oxides of nitrogen (NO{sub x}) in air. The chemistry of ground level ozone formation is complex; hundreds of types of VOCs being emitted into the atmosphere, and most of their atmospheric reactions are not completely understood. Because of this, no chemical model can be relied upon to give even approximately accurate predictions unless it has been evaluated by comparing its predictions with experimental data. Therefore an experimental and modeling study was conducted to assess how chemical mechanism evaluations using environmental chamber data are affected by the light source and other chamber characteristics. Xenon arc lights appear to give the best artificial representation of sunlight currently available, and experiments were conducted in a new Teflon chamber constructed using such a light source. Experiments were also conducted in an outdoor Teflon Chamber using new procedures to improve the light characterization, and in Teflon chambers using blacklights. These results, and results of previous runs other chambers, were compared with model predictions using an updated detailed chemical mechanism. The magnitude of the chamber radical source assumed when modeling the previous runs were found to be too high; this has implications in previous mechanism evaluations. Temperature dependencies of chamber effects can explain temperature dependencies in chamber experiments when Ta-300{degree}K, but not at temperatures below that.

  8. Scaling of bubble growth in a porous medium. Topical report

    SciTech Connect (OSTI)

    Satik, C.; Yortsos, Y.; Li, X. [Univ. of Southern California, Los Angeles, CA (United States). Dept. of Chemical Engineering

    1995-07-01T23:59:59.000Z

    Processes involving liquid-to-gas phase change in porous media are routinely encountered, for example in the recovery of oil, geothermal processes, nuclear waste disposal or enhanced heat transfer. They involve diffusion (and convection) in the pore space, driven by an imposed supersaturation in pressure or temperature. Phase change proceeds by nucleation and phase growth. Depending on pore surface roughness, a number of nucleation centers exist, thus phase growth occurs from a multitude of clusters. Contrary to growth in the bulk or in a Hele-Shaw cell, however, growth patterns in porous media are disordered and not compact. As in immiscible displacements, they reflect the underlying pore microstructure. The competition between multiple clusters is also different from the bulk. For example, cluster growth may be controlled by a combination of diffusion (e.g. Laplace equation in the quasi-static case) with percolation. Novel growth patterns axe expected from this competition. While multiple cluster growth is important, the simpler problem of single-bubble growth is still not well understood. In this section, we focus on the growth of a single bubble, subject to a fixed far-field supersaturation (e.g. by lowering the pressure in a supersaturated solution or by raising the temperature in a. superheated liquid). Our emphasis is on deriving a scaling theory for growth at conditions of quasi-static diffusion, guided by recent experimental observations. Visualization of bubble growth in model porous media was recently conducted using 2-D etched-glass micromodels.

  9. Quantum computing with single electron bubbles in helium

    E-Print Network [OSTI]

    Weijun Yao

    2005-10-27T23:59:59.000Z

    An electron inside liquid helium forms a bubble of 17 \\AA in radius. In an external magnetic field, the two-level system of a spin 1/2 electron is ideal for the implementation of a qubit for quantum computing. The electron spin is well isolated from other thermal reservoirs so that the qubit should have very long coherence time. By confining a chain of single electron bubbles in a linear RF quadrupole trap, a multi-bit quantum register can be implemented. All spins in the register can be initialized to the ground state either by establishing thermal equilibrium at a temperature around 0.1 K and at a magnetic field of 1 T or by sorting the bubbles to be loaded into the trap with magnetic separation. Schemes are designed to address individual spins and to do two-qubit CNOT operations between the neighboring spins. The final readout can be carried out through a measurement similar to the Stern-Gerlach experiment.

  10. November 8-9, 2005 Blanket Design for Large Chamber

    E-Print Network [OSTI]

    Raffray, A. René

    - Max. FS/Li interface temp. ODS Advanced Case Advanced Case RAFS RAFS ODS FS ODS FS Chamber radius, Rchamb (m) 10.5 10.5 11 11 Rep rate 5

  11. Neutral Gas Expansion in a Cylindrical Helicon Discharge Chamber

    E-Print Network [OSTI]

    Walker, Mitchell

    ­1500 G) magnetic field parallel to the axis of the tube. In many helicon experiments for basic plasma research, the discharge chamber is composed of a small diameter (2­10 cm), relatively long (0.5­1.75 m

  12. atlas muon chamber: Topics by E-print Network

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

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  13. atlas mdt chambers: Topics by E-print Network

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

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  14. atlas muon chambers: Topics by E-print Network

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

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  15. Carrying Semiautomatic Pistols with a Round in the Chamber

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

    1999-10-28T23:59:59.000Z

    Sets forth requirements for a DOE security police officer who must carry a round in the chamber of a semiautomatic pistol while on duty. Does not cancel other directives.

  16. Development of the Captive Aerosol Growth and Evolution Chamber System

    E-Print Network [OSTI]

    Antonietti, Carlos G

    2014-08-28T23:59:59.000Z

    The Captive Aerosol Growth and Evolution (CAGE) Chamber System is an tool designed to study the evolution of aerosols under conditions identical or similar to those of the surrounding environment. Our motivation was to quantify the sensitivity...

  17. A self-triggered readout for a time projection chamber

    E-Print Network [OSTI]

    Werner, Andrew Thompson, 1981-

    2004-01-01T23:59:59.000Z

    A self-triggering readout for a time projection chamber (TPC) is presented, with applications to novel forms of data acquisition for high energy physics application. The construction and initial testing of the readout ...

  18. E-Cloud Build-up in Grooved Chambers

    E-Print Network [OSTI]

    Venturini, Marco

    2007-01-01T23:59:59.000Z

    and F. Zimmermann, ”LC e-Cloud Activities at CERN”, talkal. , Simulations of the Electron Cloud for Vari- ous Con?E-CLOUD BUILD-UP IN GROOVED CHAMBERS ? M. Venturini † LBNL,

  19. Chamber technology concepts for inertial fusion energy: Three recent examples

    SciTech Connect (OSTI)

    Meier, W.R.; Moir, R.W. [Lawrence Livermore National Lab., CA (United States); Abdou, M.A. [California Univ., Los Angeles, CA (United States)

    1997-02-27T23:59:59.000Z

    The most serious challenges in the design of chambers for inertial fusion energy (IFE) are 1) protecting the first wall from fusion energy pulses on the order of several hundred megajoules released in the form of x rays, target debris, and high energy neutrons, and 2) operating the chamber at a pulse repetition rate of 5-10 Hz (i.e., re-establishing, the wall protection and chamber conditions needed for beam propagation to the target between pulses). In meeting these challenges, designers have capitalized on the ability to separate the fusion burn physics from the geometry and environment of the fusion chamber. Most recent conceptual designs use gases or flowing liquids inside the chamber. Thin liquid layers of molten salt or metal and low pressure, high-Z gases can protect the first wall from x rays and target debris, while thick liquid layers have the added benefit of protecting structures from fusion neutrons thereby significantly reducing the radiation damage and activation. The use of thick liquid walls is predicted to 1) reduce the cost of electricity by avoiding the cost and down time of changing damaged structures, and 2) reduce the cost of development by avoiding the cost of developing a new, low-activation material. Various schemes have been proposed to assure chamber clearing and renewal of the protective features at the required pulse rate. Representative chamber concepts are described, and key technical feasibility issues are identified for each class of chamber. Experimental activities (past, current, and proposed) to address these issues and technology research and development needs are discussed.

  20. Laser generation of gas bubbles: Photoacoustic and photothermal effects recorded in transient grating experiments

    SciTech Connect (OSTI)

    Frez, Clifford; Diebold, Gerald J. [Department of Chemistry, Brown University, Providence, Rhode Island 02912 (United States)

    2008-11-14T23:59:59.000Z

    Absorption of high power laser radiation by colloidal suspensions or solutions containing photoreactive chemicals can result in bubble production. Here, transient grating experiments are reported where picosecond and nanosecond lasers are used to initiate photoinduced processes that lead to bubble formation. Irradiation of colloidal Pt suspensions is found to produce water vapor bubbles that condense back to liquid on a nanosecond time scale. Laser irradiation of Pt suspensions supersaturated with CO{sub 2} liberates dissolved gas to produce bubbles at the sites of the colloidal particles. Laser induced chemical reactions that produce bubbles are found in suspensions of particulate C in water, and in the sensitized decarboxylation of oxalic acid. Theory based on linear acoustics as well as the Rayleigh-Plesset equation is given for description of the bubble motion.

  1. Effects of liquid helium bubble formation in a superconducting cavity cryogenic system

    SciTech Connect (OSTI)

    Chang, X.; Wang, E.; Xin, T.

    2011-03-01T23:59:59.000Z

    We constructed a simple prototype model based on the geometry of the 56 MHz superconducting cavity for RHIC. We studied the formation, in this prototype, of bubbles of liquid helium and their thermal effects on the cavity. We found that due to the low viscosity of the liquid helium, and its small surface tension, no large bubbles formed. The tiny bubbles, generated from most of the area, behaved like light gas travelling in a free space and escaped from the trapping region. The bubbles that were generated in the trapping area, due to its descending geometry, are much bigger than the other bubbles, but due to the liquid flow generated by heating, they still are negligible compared to the size of the trapping region. We expected that the effects of bubbles in our 56 MHz cavity during operation might well be negligible.

  2. Nucleation and evolution of false vacuum bubbles in scalar-tensor gravity

    E-Print Network [OSTI]

    Bum-Hoon Lee; Dong-han Yeom

    2011-11-01T23:59:59.000Z

    In this presentation, we discuss the nucleation and subsequent evolution of false vacuum bubbles in the scalar-tensor gravity. First, we transform the scalar-tensor type theory of gravity to the standard Brans-Dicke type. Second, we transform the Brans-Dicke type theory from the Jordan frame to the Einstein frame. For a certain potential, a true vacuum bubble in the Einstein frame can be transformed to a false vacuum bubble in the Jordan frame by a conformal transformation. Thus, in the Jordan frame, the nucleation of a false vacuum bubble can be possible and its subsequent evolution can be described with the help of thin-wall approximation. False vacuum bubbles have physical importance: a set of false vacuum bubbles might generate a negative energy bath and it has further theoretical implications.

  3. The false vacuum bubble nucleation due to a nonminimally coupled scalar field

    E-Print Network [OSTI]

    Wonwoo Lee; Bum-Hoon Lee; Chul H. Lee; Chanyong Park

    2006-06-07T23:59:59.000Z

    We study the possibility of forming the false vacuum bubble nucleated within the true vacuum background via the true-to-false vacuum phase transition in curved spacetime. We consider a semiclassical Euclidean bubble in the Einstein theory of gravity with a nonminimally coupled scalar field. In this paper we present the numerical computations as well as the approximate analytical computations. We mention the evolution of the false vacuum bubble after nucleation.

  4. False vacuum bubble nucleation due to a nonminimally coupled scalar field

    SciTech Connect (OSTI)

    Lee, Wonwoo; Park, Chanyong [Center for Quantum Spacetime, Sogang University, 121-742, Seoul (Korea, Republic of); Lee, Bum-Hoon [Department of Physics, Sogang University, Seoul 121-742 (Korea, Republic of); Center for Quantum Spacetime, Sogang University, 121-742, Seoul (Korea, Republic of); Lee, Chul H. [Department of Physics, and BK21 Division of Advanced Research and Education in Physics, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2006-12-15T23:59:59.000Z

    We study the possibility of forming the false vacuum bubble nucleated within the true vacuum background via the true-to-false vacuum phase transition in curved spacetime. We consider a semiclassical Euclidean bubble in the Einstein theory of gravity with a nonminimally coupled scalar field. In this paper we present the numerical computations as well as the approximate analytical computations. We mention the evolution of the false vacuum bubble after nucleation.

  5. Eigenmodes in Two Simplified Chamber Structures Studied for Spurious Microwaves in the APS Storage Ring Beam Chamber

    E-Print Network [OSTI]

    Kemner, Ken

    calculate the transverse electric field Ey at two points BPM+ and BPM - shown in Figures 2 and 3 the transverse electric field Ey at two points BPM+ and BPM - in the simplified chamber structure with a short

  6. Fast Track Dredged Material Decontamination

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    Fast Track Dredged Material Decontamination Demonstration for the Port of New York and New Jersey Department of Energy Brookhaven National Laboratory Fast Track Dredged Material Decontamination Demonstration .............................................................................. 3 3.3 Relation to the U.S. Army Corps of Engineers-New York District Dredged Material Management

  7. BSTBacterial Source Tracking Conference Proceedings

    E-Print Network [OSTI]

    BSTBacterial Source Tracking Conference Proceedings 2012 Bacterial Source Tracking State Conference Conference Proceedings Prepared by: Lucas Gregory, Texas Water Resources Institute Courtney Smith of the Science Conference Texas Water Resources Institute TR-427 June 2012 #12;#12;Texas Water Resources

  8. Environmental Studies Minor Sustainability Track

    E-Print Network [OSTI]

    , and decision-making in pursuit of sustainability goals Example courses: ECON 75 Environmental and Energy2/17/14 Environmental Studies Minor Sustainability Track W O R K S H E E T The sustainability track (numbered 10 or above) 1. One course in team problem-solving or design/innovation for sustainability 2. One

  9. Bubbles Help Break Energy Storage Record for Lithium Air-Batteries

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

    Bubbles Help Break Energy Storage Record for Lithium Air-Batteries Foam-base graphene keeps oxygen flowing in batteries that holds promise for electric vehicles January...

  10. Generation of laser-induced cavitation bubbles with a digital hologram

    E-Print Network [OSTI]

    Quinto-Su, P. A; Venugopalan, V.; Ohl, C.-D.

    2008-01-01T23:59:59.000Z

    C. D. Ohl, “Controlled cavitation-cell interaction: trans-R. Dijkink and C. D. Ohl, “Cavitation based micropump,” Labobservations of laser- induced cavitation bubbles in water,”

  11. Ultrasonic effect on the bubble nucleation and heat transfer of oscillating nanofluid

    SciTech Connect (OSTI)

    Zhao, Nannan; Fu, Benwei [Institute of Marine Engineering and Thermal Science, College of Marine Engineering, Dalian Maritime University, Dalian 116026 (China); Key Laboratory of Marine, Mechanical and Manufacturing Engineering of the Ministry of Transport, Dalian 116026 (China); Ma, H. B., E-mail: mah@missouri.edu [Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, Missouri 65211 (United States)

    2014-06-30T23:59:59.000Z

    Ultrasonic sound effect on bubble nucleation, oscillating motion activated by bubble formation, and its heat transfer enhancement of nanofluid was experimentally investigated. Nanofluid consists of distilled water and dysprosium (III) oxide (Dy{sub 2}O{sub 3}) nanoparticles with an average size of 98?nm and a mass ratio of 0.5%. Visualization results demonstrate that when the nanoparticles are added in the fluid influenced by the ultrasonic sound, bubble nucleation can be significantly enhanced. The oscillating motion initiated by the bubble formation of nanofluid under the influence of ultrasonic sound can significantly enhance heat transfer of nanofluid in an interconnected capillary loop.

  12. SOFTWARE QUALITY & SYSTEMS ENGINEERING PROGRAM: Project Tracking...

    Office of Environmental Management (EM)

    Project Tracking Checklist SOFTWARE QUALITY & SYSTEMS ENGINEERING PROGRAM: Project Tracking Checklist The following checklist is intended to provide system owners, project...

  13. Increasing Scientific Productivity by Tracking Data

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

    Data Tracking Increases Scientific Productivity Data Tracking Increases Scientific Productivity July 20, 2011 | Tags: HPSS, NERSC Linda Vu, lvu@lbl.gov, +1 510 486 2402 HPSS...

  14. Midwest Renewable Energy Tracking System (Multiple States)

    Broader source: Energy.gov [DOE]

    The Midwest Renewable Energy Tracking System (M-RETS®) tracks renewable energy generation in participating States and Provinces and assists in verifying compliance with individual state/provincial...

  15. June 17-21, 2007 SOFE07, Albuquerque 1 Conceptual Study of Integrated Chamber Core

    E-Print Network [OSTI]

    Raffray, A. René

    as advanced option to reduce or eliminate ion threat on chamber wall · Chamber core concept based on magnetic target (~24% of the energy is in ions and ~1% in photons), a large chamber (~10.75 m) is required options that would reduce the ion threat spectra on the armor and allow for more compact chambers

  16. LASER IFE DIRECT DRIVE CHAMBER CONCEPTS WITH MAGNETIC INTERVENTION A. R. Raffray1

    E-Print Network [OSTI]

    Raffray, A. René

    is the survival of the chamber wall under the ion threat spectra (representing ~25% of the yield energy). The possibility of steering the ions away from the chamber to specially-designed dump chambers using magnetic to accommodate the ion fluxes in the dump chamber provided the right measures are taken to prevent the liquid

  17. Aug. 8-9, 2006 HAPL meeting, GA Advanced Chamber Concept with Magnetic Intervention

    E-Print Network [OSTI]

    Raffray, A. René

    Aug. 8-9, 2006 HAPL meeting, GA 1 Advanced Chamber Concept with Magnetic Intervention: - Ion Dump and Thermal Response of Dump Plates Estimated for Cone-Shaped Chamber · For example case with ~10%of ion wall chamber to satisfy target and laser requirements ·Separate wetted wall chamber to accommodate ions

  18. High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

    E-Print Network [OSTI]

    DeCampo, J A; Raft, P D

    1972-01-01T23:59:59.000Z

    High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

  19. Alexandria fluidized-bed process-development plant: bubble characteristics

    SciTech Connect (OSTI)

    Not Available

    1982-12-01T23:59:59.000Z

    Recent studies at DOE's Alexandria Atmospheric Fluidized-Bed Combustion (AFBC) Process Development Unit (PDU) have involved experimental verifications of predictions from the Massachusetts Institute of Technology's Coal AFBC Systems Model. Although Model predictions were quite accurate in many instances, there appeared to be several significant discrepancies between predicted values and association experimental data from the 3' x 3' (nominal) combustor at Alexandria. Experimental work at Alexandria related to the MIT Model was initiated in 1980. Readers should consult previous reports for an evaluation of the Model and a comparison between the Model predictions and Alexandria experimental data. As a result of these studies, a number of information gaps within the Model's database were identified, primarily related to the fluid dynamics submodel, which might account for some of the discrepancies noted. In an attempt to support further development and calibration of the MIT Model, facilities at the Alexandria PDU were committed to providing experimental data to alleviate some of the information gaps. The specific information gap focused upon during the period of January to August 1982 involved the bubble growth submodel within the fluid dynamics portion. The specific objective involved a series of tests designed to measure bubble characteristics within both cold and hot beds. Measurements were made under a variety of different conditions. The insights gained from the bubble characteristic related testing have been passed on to DOE and MIT, and used as the basis for implementing additional model refinements. Additional model verification activity is being carried out by DOE/METC. It is recognized that additional work will be necessary for the FBC Model to achieve the goal of being a useful aid for boiler designers.

  20. Initial Back-to-Back Fission Chamber Testing in ATRC

    SciTech Connect (OSTI)

    Benjamin Chase; Troy Unruh; Joy Rempe

    2014-06-01T23:59:59.000Z

    Development and testing of in-pile, real-time neutron sensors for use in Materials Test Reactor experiments is an ongoing project at Idaho National Laboratory. The Advanced Test Reactor National Scientific User Facility has sponsored a series of projects to evaluate neutron detector options in the Advanced Test Reactor Critical Facility (ATRC). Special hardware was designed and fabricated to enable testing of the detectors in the ATRC. Initial testing of Self-Powered Neutron Detectors and miniature fission chambers produced promising results. Follow-on testing required more experiment hardware to be developed. The follow-on testing used a Back-to-Back fission chamber with the intent to provide calibration data, and a means of measuring spectral indices. As indicated within this document, this is the first time in decades that BTB fission chambers have been used in INL facilities. Results from these fission chamber measurements provide a baseline reference for future measurements with Back-to-Back fission chambers.

  1. Cooperative Modeling and Design History Tracking Using Design Tracking Matrix

    E-Print Network [OSTI]

    Kim, Jonghyun

    2010-10-12T23:59:59.000Z

    This thesis suggests a new framework for cooperative modeling which supports concurrency design protocol with a design history tracking function. The proposed framework allows designers to work together while eliminating design conflicts...

  2. Deformed bubble growth and coalescence in polymer foam processing

    E-Print Network [OSTI]

    Allaboun, Hussein Raji

    1996-01-01T23:59:59.000Z

    conditions (Table 34 0. 1 Viacoelaatic ? ? ? - - Newtoruan o. os V 2 10 4 10 6 10 8 10 1 10 1. 2 10 Time, 1* Figure 4. 1. The viscous limit of the viscoelastic melt. 35 0. 035 0. 03 0. 025 O. O2 0. 015 O. O1 - ti/90 =o. s ? ti/tl. =o. 75 q/q... q/q q/q, 0. 005 1O' 1O' 102 Time, 1* 10' 104 Figure 4. Effect of viscosity on bubble pressure. An increase in the viscosity resulted in a decrease of the rate of change of gaseous phase pressure ( See Figure 4. 2), and, consequently...

  3. Abrasion resistant track shoe grouser

    DOE Patents [OSTI]

    Fischer, Keith D; Diekevers, Mark S; Afdahl, Curt D; Steiner, Kevin L; Barnes, Christopher A

    2013-04-23T23:59:59.000Z

    A track shoe for a track-type vehicle. The track shoe includes a base plate and a grouser projecting away from the base plate. A capping surface structure of substantially horseshoe shaped cross-section is disposed across a distal portion of the grouser. The capping surface structure covers portions of a distal edge surface and adjacent lateral surfaces. The capping surface structure is formed from an material characterized by enhanced wear resistance relative to portions of the grouser underlying the capping surface structure.

  4. High resolution track etch autoradiography

    DOE Patents [OSTI]

    Solares, G.; Zamenhof, R.G.

    1994-12-27T23:59:59.000Z

    A detector assembly is disclosed for use in obtaining alpha-track autoradiographs, the detector assembly including a substantially boron-free substrate; a detector layer deposited on the substantially boron-free substrate, the detector layer being capable of recording alpha particle tracks and exhibiting evidence of the alpha tracks in response to being exposed to an etchant, the detector layer being less than about 2 microns thick; and a protective layer deposited on the detector layer, the protective layer being resistant to the etchant and having a thickness of about 0.5 to 1 microns. 13 figures.

  5. Dynamic Information Flow Tracking (DIFT) software release -Java version

    E-Print Network [OSTI]

    Crandall, Jedidiah R.

    of information simply by comparing the two vectors associated with them (e.g., using a dot product. It can be seen in the figure that Cocktail sort (a variant of Bubble sort) is very close to Bubble sort

  6. Fluorescent image tracking velocimeter

    DOE Patents [OSTI]

    Shaffer, Franklin D. (Library, PA)

    1994-01-01T23:59:59.000Z

    A multiple-exposure fluorescent image tracking velocimeter (FITV) detects and measures the motion (trajectory, direction and velocity) of small particles close to light scattering surfaces. The small particles may follow the motion of a carrier medium such as a liquid, gas or multi-phase mixture, allowing the motion of the carrier medium to be observed, measured and recorded. The main components of the FITV include: (1) fluorescent particles; (2) a pulsed fluorescent excitation laser source; (3) an imaging camera; and (4) an image analyzer. FITV uses fluorescing particles excited by visible laser light to enhance particle image detectability near light scattering surfaces. The excitation laser light is filtered out before reaching the imaging camera allowing the fluoresced wavelengths emitted by the particles to be detected and recorded by the camera. FITV employs multiple exposures of a single camera image by pulsing the excitation laser light for producing a series of images of each particle along its trajectory. The time-lapsed image may be used to determine trajectory and velocity and the exposures may be coded to derive directional information.

  7. Study of bubble growth in water pool boiling through synchronized, infrared thermometry and high-speed video

    E-Print Network [OSTI]

    Gerardi, Craig

    High-speed video and infrared thermometry were used to obtain time- and space-resolved information on bubble nucleation and heat transfer in pool boiling of water. The bubble departure diameter and frequency, growth and ...

  8. PROCEEDINGS OF THE BIOMAGNETIC EFFECTS WORKSHOP, APRIL 6-7, 1978, LAWRENCE BERKELEY LAB

    E-Print Network [OSTI]

    Tenforde, Tom S.

    2011-01-01T23:59:59.000Z

    Brookhaven bubble chamber. The black dot shows the typicalbubble chamber at Brookbaven National Laboratory. The dot

  9. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2003-04-15T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  10. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2003-04-08T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  11. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  12. The PEP-II Lower Pressure HER Vacuum Chamber

    SciTech Connect (OSTI)

    DeBarger, S.; Metcalfe, S.; Seeman, J.; Sullivan, M.; Wienands, U.; Wright, D.; /SLAC

    2006-03-13T23:59:59.000Z

    This new vacuum chamber has been installed from 12 to 21 meters upstream of the BaBar detector in the PEP-II High Energy Ring (HER) to reduce lost particle backgrounds. The backgrounds from HER now dominate the backgrounds in the BaBar detector and the present vacuum pressure is 1 x 10{sup -9} Torr. The new chamber will increase the pumping significantly by adding 18 x 2000 l/s titanium sublimation pumps to the existing 5 x 440 l/s ion pumps, and is expected to reduce the pressure by about a factor of five. Features of the chamber include improved water cooling, improved vacuum conductance through copper RF screens featuring over 15,000 small square holes and the ability to sublimate titanium while the beam is still on.

  13. Chamber Design for the Laser Inertial Fusion Energy (LIFE) Engine

    SciTech Connect (OSTI)

    Latkowski, J F; Abbott, R P; Aceves, S; Anklam, T; Badders, D; Cook, A W; DeMuth, J; Divol, L; El-Dasher, B; Farmer, J C; Flowers, D; Fratoni, M; ONeil, R G; Heltemes, T; Kane, J; Kramer, K J; Kramer, R; Lafuente, A; Loosmore, G A; Morris, K R; Moses, G A; Olson, B; Pantano, C; Reyes, S; Rhodes, M; Roe, K; Sawicki, R; Scott, H; Spaeth, M; Tabak, M; Wilks, S

    2010-11-30T23:59:59.000Z

    The Laser Inertial Fusion Energy (LIFE) concept is being designed to operate as either a pure fusion or hybrid fusion-fission system. The present work focuses on the pure fusion option. A key component of a LIFE engine is the fusion chamber subsystem. It must absorb the fusion energy, produce fusion fuel to replace that burned in previous targets, and enable both target and laser beam transport to the ignition point. The chamber system also must mitigate target emissions, including ions, x-rays and neutrons and reset itself to enable operation at 10-15 Hz. Finally, the chamber must offer a high level of availability, which implies both a reasonable lifetime and the ability to rapidly replace damaged components. An integrated design that meets all of these requirements is described herein.

  14. The role of colloidal particles on the migration of air bubbles in porous media

    E-Print Network [OSTI]

    Han, Ji-seok

    2009-05-15T23:59:59.000Z

    into account the movement of air bubbles and colloidal particle capture on discrete air-water interface. Generally colloidal particles are treated as suspended particles in the water, so the hypothesis is that the rising air bubble can collect the particles...

  15. Journal of Marine Research, 64, 7395, 2006 Constraining bubble dynamics and mixing with

    E-Print Network [OSTI]

    Hamme, Roberta C.

    at this location, because of uncertainties in air-sea heat flux estimates and bubble dynamics. Organic carbonJournal of Marine Research, 64, 73­95, 2006 Constraining bubble dynamics and mixing with dissolved R. Emerson2 ABSTRACT We used a dynamic mixed layer model to determine carbon export by the oxygen

  16. Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir

    E-Print Network [OSTI]

    Wehrli, Bernhard

    Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir Sebastian. Wehrli (2012), Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir; revised 25 November 2011; accepted 30 November 2011; published 4 January 2012. [1] Organic carbon (OC

  17. Macro-scale Bubbles for Aligning Carbon Nanotubes Jordan Hoyt,1

    E-Print Network [OSTI]

    UG-18 Macro-scale Bubbles for Aligning Carbon Nanotubes Jordan Hoyt,1 Shota Ushiba,2-wall carbon nanotubes (SWCNTs) exhibit high aspect ratios that can lead to extreme anisotropic mechanical-scale bubble structures to align SWCNTs in larger quantities and in less time compared to pre-existing methods

  18. Effect of charge on the dynamics of an acoustically forced bubble

    E-Print Network [OSTI]

    Hongray, Thotreithem; Balakrishnan, J

    2013-01-01T23:59:59.000Z

    The effect of charge on the dynamics of a gas bubble undergoing forced oscillations in a liquid due to incidence of an ultrasonic wave is theoretically investigated. The limiting values of the possible charge a bubble may physically carry are obtained. The presence of charge influences the regime in which the bubble's radial oscillations fall. The extremal compressive and expansive dimensions of the bubble are also studied as a function of the amplitude of the driving pressure. It is shown that the limiting value of the bubble charge is dictated both by the minimal value reachable of the bubble radius as well as the amplitude of the driving ultrasound pressure wave. A non-dimensional ratio zeta is defined that is a comparative measure of the extremal values the bubble can expand or contract to and find the existence of an unstable regime for zeta as a function of the driving pressure amplitude, Ps. This unstable regime is gradually suppressed with increasing bubble size. The Blake and the upper transient pres...

  19. Effect of charge on the dynamics of an acoustically forced bubble

    E-Print Network [OSTI]

    Thotreithem Hongray; B. Ashok; J. Balakrishnan

    2013-04-17T23:59:59.000Z

    The effect of charge on the dynamics of a gas bubble undergoing forced oscillations in a liquid due to incidence of an ultrasonic wave is theoretically investigated. The limiting values of the possible charge a bubble may physically carry are obtained. The presence of charge influences the regime in which the bubble's radial oscillations fall. The extremal compressive and expansive dimensions of the bubble are also studied as a function of the amplitude of the driving pressure. It is shown that the limiting value of the bubble charge is dictated both by the minimal value reachable of the bubble radius as well as the amplitude of the driving ultrasound pressure wave. A non-dimensional ratio zeta is defined that is a comparative measure of the extremal values the bubble can expand or contract to and find the existence of an unstable regime for zeta as a function of the driving pressure amplitude, Ps. This unstable regime is gradually suppressed with increasing bubble size. The Blake and the upper transient pressure thresholds for the system are then discussed.

  20. ensl-00167302,version1-18Aug2007 Measurement of particle and bubble accelerations in turbulence

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ensl-00167302,version1-18Aug2007 Measurement of particle and bubble accelerations in turbulence R motion are resolved and the particle acceleration is measured. For neutrally buoyant par- ticles, our 1.4) and to air bubbles. We observe that the acceleration variance strongly depends on the particle

  1. Can 2HDM support fermion-stabilized bubbles of false vacuum?

    E-Print Network [OSTI]

    I. P. Ivanov

    2007-07-01T23:59:59.000Z

    The Higgs potential of the two-Higgs-doublet model can have several minima with different properties. We discuss a possibility that a heavy fermion, if trapped in a microscopic false vacuum bubble, might become light enough to prevent the bubble from the collapse.

  2. Plasma Line Emission during Single-Bubble Cavitation David J. Flannigan and Kenneth S. Suslick*

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Plasma Line Emission during Single-Bubble Cavitation David J. Flannigan and Kenneth S. Suslick-bubble cavitation in sulfuric acid are reported. The excited states responsible for these emission lines range 8.3 e the plasma generated during cavitation is comprised of highly energetic particles. DOI: 10.1103/Phys

  3. Luminescence from acoustic-driven laser-induced cavitation bubbles Claus-Dieter Ohl*

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Luminescence from acoustic-driven laser-induced cavitation bubbles Claus-Dieter Ohl* Drittes and on the cavitation luminescence of a transient laser-induced bubble is investigated experimentally. The variation.60.Mq, 47.55.Bx, 47.55.Dz A vast concentration of energy occurs during the collapse of a cavitation

  4. Modeling of Taylor bubble rising in a vertical mini noncircular channel filled with a stagnant liquid

    E-Print Network [OSTI]

    Zhao, Tianshou

    of the liquid phase coupled with the equations of the force balance at the bubble interface. The predicted drift by the interfacial curvature variations along bubble length, gravity, and viscous force. The interfacial profiles gas reservoir during gas production, in chemical and nuclear reactors, and numerous heat transport

  5. 10.1098/rspa.2002.1063 Acoustic resonances in the bubble plume

    E-Print Network [OSTI]

    Buckingham, Michael

    ratio, that is, the ratio of the air-to-water volume fluxes in the jet, and the unspecified constant to chemical mixing processes, aeration of fluids and gas transfer across the air­sea interface. Also important be due to the resonances of individual bubbles, since the bubble sizes required are much larger than

  6. GLOBAL EXISTENCE FOR A TRANSLATING NEAR-CIRCULAR HELE-SHAW BUBBLE WITH SURFACE TENSION

    E-Print Network [OSTI]

    Tanveer, Saleh

    GLOBAL EXISTENCE FOR A TRANSLATING NEAR-CIRCULAR HELE-SHAW BUBBLE WITH SURFACE TENSION J. YE1 AND S for any nonzero surface tension despite the fact that a local planar approximation near the front problem, Dissipative equations, Hele-Shaw prob- lem, Translating bubbles, Surface tension Mathematics

  7. Impact of boundaries on velocity profiles in bubble rafts Yuhong Wang, Kapilanjan Krishan, and Michael Dennin

    E-Print Network [OSTI]

    Dennin, Michael

    92697-4575 (Dated: November 7, 2005) Under conditions of sufficiently slow flow, foams, colloids, and an important issue in these systems is the role of the confining boundaries. For foams, three basic systems); and confined bubble rafts (bubbles confined between the surface of water below and a glass plate on top). Often

  8. 6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines 1/4energy-daily.com/.../The_use_of_acoustic_inversion_to_estimate_the_bubble_size_distribution_in_...

    E-Print Network [OSTI]

    Sóbester, András

    6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines 1 address ... yes . . . The use of acoustic inversion to estimate the bubble size distribution in pipelines devised a new method to more accurately measure gas bubbles in pipelines. The ability to measure gas

  9. Method to calibrate fission chambers in Campbelling mode

    SciTech Connect (OSTI)

    Geslot, Benoit; Filliatre, Philippe; Jammes, Christian; Di Salvo, Jacques; Breaud, Stephane; Villard, Jean-Francois [CEA, DEN, Cadarache, SPEx, LDCI, F-13108 S Paul Lez Durance, (France); Unruh, Troy C. [INL, Idaho Natl Lab, Idaho Falls, ID 83415 (United States)

    2012-08-15T23:59:59.000Z

    Fission chambers are neutron detectors which are widely used to instrument experimental reactors such as material testing reactors or zero power reactors. In the presence of a high level mixed gamma and neutron flux, fission chambers can be operated in Campbelling mode (also known as 'fluctuation mode' or 'mean square voltage mode') to provide reliable and precise neutron related measurements. Fission chamber calibration in Campbelling mode (in terms of neutron flux) is usually done empirically using a calibrated reference detector. A major drawback of this method is that calibration measurements have to be performed in a neutron environment very similar to the one in which the calibrated detector will be used afterwards. What is proposed here is a different approach based on characterizing the fission chamber response in terms of fission rate. This way, the detector calibration coefficient is independent from the neutron spectrum and can be determined prior to the experiment. The fissile deposit response to the neutron spectrum can then be assessed independently by other means (experimental or numerical). In this paper, the response of CEA-made miniature fission chambers in Campbelling mode is studied. A theoretical model of the signal is used to calculate the calibration coefficient. The model's input parameters come from statistical distribution of individual pulses. Supporting measurements were made in the CEA Cadarache zero power reactor MINERVE and results are compared to an empirical Campbelling mode calibration. The tested fission chamber calibration coefficient is roughly 2*10{sup -26} A{sup 2}/Hz/(c/s). Both numerical and empirical methods give consistent results, however a deviation of about 15% was observed. (authors)

  10. Master track Theoretical Biology & Bioinformatics

    E-Print Network [OSTI]

    Utrecht, Universiteit

    their master. Our two MSc courses "Computational Biology" and "Bioinformatics and Evolutionary GenomicsMaster track Theoretical Biology & Bioinformatics Modeling and bioinformatics is an important Biology & Bioinformatics provides courses introducing you to the basic concepts of modeling

  11. First detection of tracks of radon progeny recoils by MIMAC

    E-Print Network [OSTI]

    Riffard, Q; Bosson, G; Bourrion, O; Descombes, T; Fourel, C; Guillaudin, O; Muraz, J -F; Colas, P; Ferrer-Ribas, E; Giomataris, I; Busto, J; Fouchez, D; Tao, C; Lebreton, L; Maire, D

    2015-01-01T23:59:59.000Z

    The MIMAC experiment is a $\\mu$-TPC matrix project for directional dark matter search. Directional detection is a strategy based on the measurement of the WIMP flux anisotropy due to the solar system motion with respect to the dark matter halo. The main purpose of MIMAC project is the measurement of the energy and the direction of nuclear recoils in 3D produced by elastic scattering of WIMPs. Since June 2012 a bi-chamber prototype is operating at the Modane underground laboratory. In this paper, we report the first ionization energy and 3D track observations of nuclear recoils produced by the radon progeny. This measurement shows the capability of the MIMAC detector and opens the possibility to explore the low energy recoil directionality signature.

  12. First detection of tracks of radon progeny recoils by MIMAC

    E-Print Network [OSTI]

    Q. Riffard; D. Santos; G. Bosson; O. Bourrion; T. Descombes; C. Fourel; O. Guillaudin; J. -F. Muraz; P. Colas; E. Ferrer-Ribas; I. Giomataris; J. Busto; D. Fouchez; C. Tao; L. Lebreton; D. Maire

    2015-04-22T23:59:59.000Z

    The MIMAC experiment is a $\\mu$-TPC matrix project for directional dark matter search. Directional detection is a strategy based on the measurement of the WIMP flux anisotropy due to the solar system motion with respect to the dark matter halo. The main purpose of MIMAC project is the measurement of the energy and the direction of nuclear recoils in 3D produced by elastic scattering of WIMPs. Since June 2012 a bi-chamber prototype is operating at the Modane underground laboratory. In this paper, we report the first ionization energy and 3D track observations of nuclear recoils produced by the radon progeny. This measurement shows the capability of the MIMAC detector and opens the possibility to explore the low energy recoil directionality signature.

  13. Chamber and target technology development for inertial fusion energy

    SciTech Connect (OSTI)

    Abdou, M; Besenbruch, G; Duke, J; Forman, L; Goodin, D; Gulec, K; Hoffer, J; Khater, H; Kulcinsky, G; Latkowski, J F; Logan, B G; Margevicious, B; Meier, W R; Moir, R W; Morley, N; Nobile, A; Payne, S; Peterson, P F; Peterson, R; Petzoldt, R; Schultz, K; Steckle, W; Sviatoslavsky, L; Tillack, M; Ying, A

    1999-04-07T23:59:59.000Z

    Fusion chambers and high pulse-rate target systems for inertial fusion energy (IFE) must: regenerate chamber conditions suitable for target injection, laser propagation, and ignition at rates of 5 to 10 Hz; extract fusion energy at temperatures high enough for efficient conversion to electricity; breed tritium and fuel targets with minimum tritium inventory; manufacture targets at low cost; inject those targets with sufficient accuracy for high energy gain; assure adequate lifetime of the chamber and beam interface (final optics); minimize radioactive waste levels and annual volumes; and minimize radiation releases under normal operating and accident conditions. The primary goal of the US IFE program over the next four years (Phase I) is to develop the basis for a Proof-of-Performance-level driver and target chamber called the Integrated Research Experiment (IRE). The IRE will explore beam transport and focusing through prototypical chamber environment and will intercept surrogate targets at high pulse rep-rate. The IRE will not have enough driver energy to ignite targets, and it will be a non-nuclear facility. IRE options are being developed for both heavy ion and laser driven IFE. Fig. 1 shows that Phase I is prerequisite to an IRE, and the IRE plus NIF (Phase II) is prerequisite to a high-pulse rate. Engineering Test Facility and DEMO for IFE, leading to an attractive fusion power plant. This report deals with the Phase-I R&D needs for the chamber, driver/chamber interface (i.e., magnets for accelerators and optics for lasers), target fabrication, and target injection; it is meant to be part of a more comprehensive IFE development plan which will include driver technology and target design R&D. Because of limited R&D funds, especially in Phase I, it is not possible to address the critical issues for all possible chamber and target technology options for heavy ion or laser fusion. On the other hand, there is risk in addressing only one approach to each technology option. Therefore, in the following description of these specific feasibility issues, we try to strike a balance between narrowing the range of recommended R&D options to minimize cost, and keeping enough R&D options to minimize risk.

  14. Single chamber fuel cells: Flow geometry, rate and composition considerations

    SciTech Connect (OSTI)

    Stefan, Ionel C.; Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2003-11-17T23:59:59.000Z

    Four different single chamber fuel cell designs were compared using propane-air gas mixtures. Gas flow around the electrodes has a significant influence on the open circuit voltage and the power density of the cell. The strong influence of flow geometry is likely due to its effect on gas composition, particularly on the oxygen chemical potential at the two electrodes as a result of gas mixing. The chamber design which exposes the cathode first to the inlet gas was found to yield the best performance at lower flow rates, while the open tube design with the electrodes equally exposed to the inlet gas worked best at higher flow rates.

  15. Kinetics of Conversion of Air Bubbles to Air-Hydrate Crystals in Antarctic Ice

    E-Print Network [OSTI]

    P. B. Price

    1995-01-23T23:59:59.000Z

    The depth-dependence of bubble concentration at pressures above the transition to the air hydrate phase and the optical scattering length due to bubbles in deep ice at the South Pole are modeled using diffusion-growth data from the laboratory, taking into account the dependence of age and temperature on depth in the ice. The model fits the available data on bubbles in cores from Vostok and Byrd and on scattering length in deep ice at the South Pole. It explains why bubbles and air hydrate crystals co-exist in deep ice over a range of depths as great as 800 m and predicts that at depths below $\\rm \\sim$ 1400 m the AMANDA neutrino observatory at the South Pole will operate unimpaired by light scattering from bubbles.

  16. A hot bubble at the centre of M81

    E-Print Network [OSTI]

    Ricci, T V; Giansante, L

    2015-01-01T23:59:59.000Z

    Context. Messier 81 has the nearest active nucleus with broad H$\\alpha$ emission. A detailed study of this galaxy's centre is important for understanding the innermost structure of the AGN phenomenon. Aims. Our goal is to seek previously undetected structures using additional techniques to reanalyse a data cube obtained with the GMOS-IFU installed on the Gemini North telescope (Schnorr M\\"uller et al. 2011). Method. We analysed the data cube using techniques of noise reduction, spatial deconvolution, starlight subtraction, PCA tomography, and comparison with HST images. Results. We identified a hot bubble with T $>$ 43500 K that is associated with strong emission of [N II]$\\lambda$5755\\AA\\ and a high [O I]$\\lambda$6300/H$\\alpha$ ratio; the bubble displays a bluish continuum, surrounded by a thin shell of H$\\alpha$ + [N II] emission. We also reinterpret the outflow found by Schnorr M\\"uller et al. (2011) showing that the blueshifted cone nearly coincides with the radio jet, as expected. Conclusions. We interpr...

  17. Non-SUSY $p$-branes, bubbles and tubular branes

    E-Print Network [OSTI]

    J. X. Lu; S. Roy

    2006-04-26T23:59:59.000Z

    We consider non-supersymmetric $p$-brane solutions of type II string theories characterized by three parameters. When the charge parameter vanishes and one of the other two takes a specific value, the corresponding chargeless solutions can be regular and describe ``bubbles'' in static (unstable) equilibrium when lifted to $d = 11$. In appropriate coordinates, they represent D6 branes with a tubular topology R$^{1,p}$ $\\times$ S$^{6-p}$ when reduced to $d=10$, called the tubular D6 branes, held in static equilibrium by a fixed magnetic flux (fluxbrane). Moreover, a `rotation parameter' can be introduced to either of the above two eleven dimensional configurations, giving rise to a generalized configuration labelling by the parameter. As such, it brings out the relations among non-supersymmetric $p$-branes, bubbles and tubular D6 branes. Given our understanding on tubular D6 branes, we are able to reinforce the interpretation of the chargeless non-supersymmetric $p$-branes as representing $p$-brane-anti$p$-brane (or non-BPS $p$-brane) systems, and understand the static nature and various singularities of these systems in a classical supergravity approximation.

  18. Observer dependence of bubble nucleation and Schwinger pair production

    SciTech Connect (OSTI)

    Garriga, Jaume [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Kanno, Sugumi; Vilenkin, Alexander [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155 (United States); Sasaki, Misao [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan); Soda, Jiro, E-mail: jaume.garriga@ub.edu, E-mail: sugumi@cosmos.phy.tufts.edu, E-mail: misao@yukawa.kyoto-u.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp, E-mail: vilenkin@cosmos.phy.tufts.edu [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2012-12-01T23:59:59.000Z

    Pair production in a constant electric field is closely analogous to bubble nucleation in a false vacuum. The classical trajectories of the pairs are Lorentz invariant, but it appears that this invariance should be broken by the nucleation process. Here, we use a model detector, consisting of other particles interacting with the pairs, to investigate how pair production is seen by different Lorentzian observers. We focus on the idealized situation where a constant external electric field is present for an infinitely long time, and we consider the in-vacuum state for a charged scalar field that describes the nucleating pairs. The in-vacuum is defined in terms of modes which are positive frequency in the remote past. Even though the construction uses a particular reference frame and a gauge where the vector potential is time dependent, we show explicitly that the resulting quantum state is Lorentz invariant. We then introduce a ''detector'' particle which interacts with the nucleated pairs, and show that all Lorentzian observers will see the particles and antiparticles nucleating preferentially at rest in the detector's rest frame. Similar conclusions are expected to apply to bubble nucleation in a sufficiently long lived vacuum. We also comment on certain unphysical aspects of the Lorentz invariant in-vacuum, associated with the fact that it contains an infinite density of particles. This can be easily remedied by considering Lorentz breaking initial conditions.

  19. Track 4: Employee Health and Wellness

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 4: Employee Health and Wellness

  20. The Laser of the ALICE Time Projection Chamber

    E-Print Network [OSTI]

    G. Renault; B. S. Nielsen; J. Westergaard; J. J. GaardhØJe

    2007-03-27T23:59:59.000Z

    The large TPC ($95 \\mathrm{m}^3$) of the ALICE detector at the CERN LHC was commissioned in summer 2006. The first tracks were observed both from the cosmic ray muons and from the laser rays injected into the TPC. In this article the basic principles of operating the $266 \\mathrm{nm}$ lasers are presented, showing the installation and adjustment of the optical system and describing the control system. To generate the laser tracks, a wide laser beam is split into several hundred narrow beams by fixed micro-mirrors at stable and known positions throughout the TPC. In the drift volume, these narrow beams generate straight tracks at many angles. Here we describe the generation of the first tracks and compare them with simulations.

  1. Computation of azimuthal combustion instabilities in an helicopter combustion chamber

    E-Print Network [OSTI]

    Nicoud, Franck

    Computation of azimuthal combustion instabilities in an helicopter combustion chamber C. Sensiau to compute azimuthal combustion instabilities is presented. It requires a thermoacoustic model using a n - formulation for the coupling between acoutics and combustion. The parameters n and are computed from a LES

  2. LASER FUSION CHAMBER DESIGN James P. Blanchard1

    E-Print Network [OSTI]

    Raffray, A. René

    the energy emitted by the target in such a way that the plant can achieve a commercially viable power approaches required for commercially viable laser fusion power plants, the issues driving those designs define the chamber size by providing flux limits for the various threats. In cases where a dry

  3. Thermodynamic Analysis of a single chamber Microbial Eric A. Zielke

    E-Print Network [OSTI]

    Thermodynamic Analysis of a single chamber Microbial Fuel Cell Eric A. Zielke May 5, 2006 #12;Microbial Fuel Cell Zielke ii List of Tables 1 First Law Thermodynamic Efficiencies from Experimental Data . . . . . . . 9 #12;Microbial Fuel Cell Zielke iii List of Figures 1 Representation of Anaerobic (anode portion

  4. QER- Comment of PA Chamber of Business and Industry

    Broader source: Energy.gov [DOE]

    On behalf of Gene Barr, President & CEO of the Pennsylvania Chamber of Business and Industry, please find attached our comments regarding Natural Gas Transmission, Storage & Distribution, Pittsburgh, Pennsylvania July 21, 2014. Thanks in advance for the attention to our comments and for holding a hearing today in our state. All the best, Kevin

  5. Modeling chamber transport for heavy-ion fusion

    SciTech Connect (OSTI)

    Sharp, W.M.; Callahan, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.; Welch, D.R.; Rose, D.V.; Olson, C.L.

    2002-10-01T23:59:59.000Z

    In a typical thick-liquid-wall scenario for heavy-ion fusion (HIF), between seventy and two hundred high-current beams enter the target chamber through ports and propagate about three meters to the target. Since molten-salt jets are planned to protect the chamber wall, the beams move through vapor from the jets, and collisions between beam ions and this background gas both strip the ions and ionize the gas molecules. Radiation from the preheated target causes further beam stripping and gas ionization. Due to this stripping, beams for heavy-ion fusion are expected to require substantial neutralization in a target chamber. Much recent research has, therefore, focused on beam neutralization by electron sources that were neglected in earlier simulations, including emission from walls and the target, photoionization by the target radiation, and pre-neutralization by a plasma generated along the beam path. When these effects are included in simulations with practicable beam and chamber parameters, the resulting focal spot is approximately the size required by a distributed radiator target.

  6. Sound Waves Excitation by Jet-Inflated Bubbles in Clusters of Galaxies

    E-Print Network [OSTI]

    Assaf Sternberg; Noam Soker

    2008-08-17T23:59:59.000Z

    We show that repeated sound waves in the intracluster medium (ICM) can be excited by a single inflation episode of an opposite bubble pair. To reproduce this behavior in numerical simulations the bubbles should be inflated by jets, rather than being injected artificially. The multiple sound waves are excited by the motion of the bubble-ICM boundary that is caused by vortices inside the inflated bubbles and the backflow (`cocoon') of the ICM around the bubble. These sound waves form a structure that can account for the ripples observed in the Perseus cooling flow cluster. We inflate the bubbles using slow massive jets, with either a wide opening angle or that are precessing. The jets are slow in the sense that they are highly sub-relativistic, $v_j \\sim 0.01c-0.1c$, and they are massive in the sense that the pair of bubbles carry back to the ICM a large fraction of the cooling mass, i.e., $\\sim 1-50 M_\\odot \\yr^{-1}$. We use a two-dimensional axisymmetric (referred to as 2.5D) hydrodynamical numerical code (VH-1).

  7. Gas-bubble growth mechanisms in the analysis of metal fuel swelling

    SciTech Connect (OSTI)

    Gruber, E.E.; Kramer, J.M.

    1986-06-01T23:59:59.000Z

    During steady-state irradiation, swelling rates associated with growth of fission-gas bubbles in metallic fast reactor fuels may be expected to remain small. As a consequence, bubble-growth mechanisms are not a major consideration in modeling the steady-state fuel behavior, and it is usually adequate to consider the gas pressure to be in equilibrium with the external pressure and surface tension restraint. On transient time scales, however, various bubble-growth mechanisms become important components of the swelling rate. These mechanisms include growth by diffusion, for bubbles within grains and on grain boundaries; dislocation nucleation at the bubble surface, or ''punchout''; and bubble growth by creep. Analyses of these mechanisms are presented and applied to provide information on the conditions and the relative time scales for which the various processes should dominate fuel swelling. The results are compared to a series of experiments in which the swelling of irradiated metal fuel was determined after annealing at various temperatures and pressures. The diffusive growth of bubbles on grain boundaries is concluded to be dominant in these experiments.

  8. Oscillating axion bubbles as alternative to supermassive black holes at galactic centers

    E-Print Network [OSTI]

    Anatoly A. Svidzinsky

    2007-10-30T23:59:59.000Z

    Recent observations of near-infrared and X-ray flares from Sagittarius A*, which is believed to be a supermassive black hole at the Galactic center, show that the source exhibits about 20-minute periodic variability. Here we provide arguments based on a quantitative analysis that supermassive objects at galactic centers may be bubbles of dark matter axions rather than black holes. An oscillating axion bubble can explain periodic variability of Sagittarius A* and yields the axion mass about 0.6 meV which fits in the open axion mass window. The bubble scenario with no other free parameters explains lack of supermassive "black holes" with mass Maxion bubble can not exceed 1.5\\times 10^9 M_{Sun}, in agreement with the upper limit on the supermassive "black hole" mass obtained from observations. Our finding, if confirmed, suggests that Einstein general relativity is invalid for strong gravity and the gravitational field for the bubble effectively becomes repulsive at large potential. Imaging a shadow of the "black hole" at the Galactic center with VLBI in the next decade can distinguish between the black hole and the oscillating axion bubble scenarios. In the case of axion bubble, a steady shadow will not be observed. Instead, the shadow will appear and disappear periodically with a period of about 20 min.

  9. On He bubbles in neutron irradiated SYLRAMIC type SiC fibers

    SciTech Connect (OSTI)

    Gelles, David S.; Youngblood, Gerald E.

    2006-03-01T23:59:59.000Z

    SylramicTM type SiC fibers, which contain at least 2.3 wt% B, were examined by TEM following neutron irradiation to dose levels of ~7 dpa in HFIR at 800°C and to ~1 dpa in ATR at 1090°C. At these radiation damage dose levels, transmutation of the boron-10 component effectively “dopes” the Sylramic? type fibers with up to 10,000 appm helium. Following irradiation at 800°C, bubble development was too fine to resolve even by high resolution TEM. However, following irradiation at 1090°C helium bubble development was resolvable, but complex. A fine dispersion of 1-nm bubbles was observed within the SiC grains and a coarse, non-uniform distribution of irregular 25-nm bubbles was observed on grain boundaries. In addition, some unusual arrays of planar 2.5-nm thick bubbles were observed in the SiC grains and equiaxed bubbles were observed in the boride precipitate particles contained within the fiber microstructure. Not unexpectedly, helium retention and bubble formation in ?-SiC depends on details of the polycrystalline microstructure as well as the irradiation conditions.

  10. Molecular Dynamics Simulation of Cascade-Induced Ballistic Helium Resolutioning from Bubbles in Iron

    SciTech Connect (OSTI)

    Stoller, Roger E [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    Molecular dynamics simulations have been used to assess the ability of atomic displacement cascades to eject helium from small bubbles in iron. This study of the ballistic resolutioning mechanism employed a recently-developed Fe-He interatomic potential in concert with an iron potential developed by Ackland and co-workers. The primary variables examined were: irradiation temperature (100 and 600K), cascade energy (5 and 20 keV), bubble radius (0.5 and 1.0 nm), and He-to-vacancy ratio in the bubble (0.25, 0.5 and 1.0). Systematic trends were observed for each of these variables. For example, ballistic resolutioning leads to a greater number of helium atoms being displaced from larger bubbles and from bubbles that have a higher He/vacancy ratio (bubble pressure). He resolutioning was reduced at 600K relative to 100K, and for 20 keV cascades relative to 5 keV cascades. Overall, the results indicate a modest level of He removal by ballistic resolutioning. The results can be used to provide guidance in selection of a resolution parameter that can be employed in cluster dynamics models to predict the bubble size distribution that evolves under irradiation.

  11. Eternal inflation, bubble collisions, and the disintegration of the persistence of memory

    SciTech Connect (OSTI)

    Freivogel, Ben [Berkeley Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720-7300 (United States); Kleban, Matthew [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Nicolis, Alberto [Department of Physics and ISCAP, Columbia University, New York, NY 10027 (United States); Sigurdson, Kris, E-mail: freivogel@berkeley.edu, E-mail: mk161@nyu.edu, E-mail: nicolis@phys.columbia.edu, E-mail: krs@phas.ubc.ca [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)

    2009-08-01T23:59:59.000Z

    We compute the probability distribution for bubble collisions in an inflating false vacuum which decays by bubble nucleation. Our analysis generalizes previous work of Guth, Garriga, and Vilenkin to the case of general cosmological evolution inside the bubble, and takes into account the dynamics of the domain walls that form between the colliding bubbles. We find that incorporating these effects changes the results dramatically: the total expected number of bubble collisions in the past lightcone of a typical observer is N ? ? V{sub f}/V{sub i} , where ? is the fastest decay rate of the false vacuum, V{sub f} is its vacuum energy, and V{sub i} is the vacuum energy during inflation inside the bubble. This number can be large in realistic models without tuning. In addition, we calculate the angular position and size distribution of the collisions on the cosmic microwave background sky, and demonstrate that the number of bubbles of observable angular size is N{sub LS} ? (?{sub k}){sup 1/2}N, where ?{sub k} is the curvature contribution to the total density at the time of observation. The distribution is almost exactly isotropic.

  12. Mechanical Feedback: From stellar wind bubbles to starbursts

    E-Print Network [OSTI]

    M. S. Oey; C. J. Clarke; P. Massey

    2001-03-20T23:59:59.000Z

    The current understanding of mechanical feedback is reviewed by evaluating the standard, adiabatic model for shell formation and evolution. This model is relevant to phenomena ranging from individual stellar-wind bubbles to galactic superwinds, forming the basis for our understanding of the multiphase ISM, IGM, and galactic evolutionary processes. Although significant discrepancies between the model and observation have been identified, to date there are none that require a fundamental revision. A variety of evidence, ranging over three orders of magnitude in spatial scale, is broadly consistent with the standard model. This includes kinematics of individual objects, observations of hot gas, the size distribution of HI shells, and outflow rates from starburst galaxies. However, some of the most pressing issues relating to shell evolution are still outstanding and obstruct efforts to resolve key questions like the fate of the hot gas.

  13. Bubble formation in reservoir fluids at low supersaturations

    E-Print Network [OSTI]

    Wieland, Denton R

    1956-01-01T23:59:59.000Z

    reservoir cox'e, oil and gca obtcfned directly from the Ranf;oly Field in Color: Co, &cod mounted the core in ' Gap'"cr afz'ilier to the coro tlountiflf' re' orted in this ~mr%, Tho oil:nd g:. a ~me reconMned:n the 1abora- tory uith u bubble point ox lg...;te rrd one ron thc c!;-ber ho using, vere coi. "ected to a c ~urce 'f 9. C, current crx'. tc s circuit br+, l. cr &Nicli rc:. iiyc'. ll c. illic-~ores to operate !Lon the v; lvc sto M. ached ti;e pl. ". te the electrical circuit vo 1~'. be closed ~nd...

  14. Coalescence of bubbles and drops in an outer fluid

    E-Print Network [OSTI]

    Joseph D. Paulsen; Rémi Carmigniani; Anerudh Kannan; Justin C. Burton; Sidney R. Nagel

    2014-07-24T23:59:59.000Z

    When two liquid drops touch, a microscopic connecting liquid bridge forms and rapidly grows as the two drops merge into one. Whereas coalescence has been thoroughly studied when drops coalesce in vacuum or air, many important situations involve coalescence in a dense surrounding fluid, such as oil coalescence in brine. Here we study the merging of gas bubbles and liquid drops in an external fluid. Our data indicate that the flows occur over much larger length scales in the outer fluid than inside the drops themselves. Thus we find that the asymptotic early regime is always dominated by the viscosity of the drops, independent of the external fluid. A phase diagram showing the crossovers into the different possible late-time dynamics identifies a dimensionless number that signifies when the external viscosity can be important.

  15. BEBC hydrolic apparatus

    E-Print Network [OSTI]

    The 3.70 metre Big European Bubble Chamber (BEBC) was dismantled on 9 August 1984. One of the biggest detectors in the world, it produced direct visual recording of particle tracks. 6.3 million photos of interactions were taken with the chamber in the course of its existence.

  16. 'Radon Concentration Survey in Inner Rooms from Deputy Chamber and National Congress-Brasilia/DF'

    SciTech Connect (OSTI)

    Nicoli, Ieda Gomes [Escritorio de Brasilia-CNEN Quadra 4 Bl. B Sala 1002 A Setor Comercial Norte CEP 70714-900 Brasilia-DF (Brazil); Cardozo, Katia Maria [Instituto de Engenharia Nuclear-CNEN Rua Helio de Almeida, 75--Cidade Universitaria-Ilha do Fundao CEP 21941-906-Caixa Postal 68550 Rio de Janeiro-RJ (Brazil); Azevedo Gouvea, Vandir de [Divisao de Materias Primas e Minerais-DIMAP-CNEN Rua General Severiano, 90-Botafogo CEP 22290-901 Rio de Janeiro-RJ (Brazil)

    2008-08-07T23:59:59.000Z

    Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasilia--DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of {sup 222}Rn contents. Derived values, whose average value was about 73 Bq/m{sup 3}, were all under maximum permissible limits for radon 200 Bq/m{sup 3}, established by International Comission on Radiological Protection--ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Braselia with effective participation of Nuclear Engineering Institute from CNEN--RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors.

  17. Objective: Determine the energy use of two greenhouse insulation technologies (a bubble insulation system and an energy/shade screen) retrofitted into plastic covered greenhouses, and compare the

    E-Print Network [OSTI]

    Vermont, University of

    Objective: Determine the energy use of two greenhouse insulation technologies (a bubble insulation structures. 1. Unimproved standard double-layer poly inflated greenhouse (control) 2. Bubble insulation is around 1-2, compared to an estimated 30 for the bubble system. What did we learn? The bubble insulation

  18. WPo4.9 SIMULATION OF IFE CHAMBER DYNAMIC RESPONSE BY A SECOND ORDER GODUNOV METHOD WITH ARBITRARY GEOMETRY

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    explosion. After the target-generated X-rays and ion debris traverse the chamber, the chamber environment scale occur in the chamber following the target explosion. The resultant X-rays, ion debris and neutron from the target travel through the chamber. Depending on the chamber constituents, X-rays and ion

  19. The Majorana Parts Tracking Database

    E-Print Network [OSTI]

    Abgrall, N; Avignone, F T; Bertrand, F E; Brudanin, V; Busch, M; Byram, D; Caldwell, A S; Chan, Y-D; Christofferson, C D; Combs, D C; Cuesta, C; Detwiler, J A; Doe, P J; Efremenko, Yu; Egorov, V; Ejiri, H; Elliott, S R; Esterline, J; Fast, J E; Finnerty, P; Fraenkle, F M; Galindo-Uribarri, A; Giovanetti, G K; Goett, J; Green, M P; Gruszko, J; Guiseppe, V E; Gusev, K; Hallin, A L; Hazama, R; Hegai, A; Henning, R; Hoppe, E W; Howard, S; Howe, M A; Keeter, K J; Kidd, M F; Kochetov, O; Kouzes, R T; LaFerriere, B D; Leon, J Diaz; Leviner, L E; Loach, J C; MacMullin, J; Martin, R D; Meijer, S J; Mertens, S; Miller, M L; Mizouni, L; Nomachi, M; Orrell, J L; O'Shaughnessy, C; Overman, N R; Petersburg, R; Phillips, D G; Poon, A W P; Pushkin, K; Radford, D C; Rager, J; Rielage, K; Robertson, R G H; Romero-Romero, E; Ronquest, M C; Shanks, B; Shima, T; Shirchenko, M; Snavely, K J; Snyder, N; Soin, A; Suriano, A M; Tedeschi, D; Thompson, J; Timkin, V; Tornow, W; Trimble, J E; Varner, R L; Vasilyev, S; Vetter, K; Vorren, K; White, B R; Wilkerson, J F; Wiseman, C; Xu, W; Yakushev, E; Young, A R; Yu, C -H; Zhitnikov, I

    2015-01-01T23:59:59.000Z

    The Majorana Demonstrator is an ultra-low background physics experiment searching for the neutrinoless double beta decay of $^{76}$Ge. The Majorana Parts Tracking Database is used to record the history of components used in the construction of the Demonstrator. The tracking implementation takes a novel approach based on the schema-free database technology CouchDB. Transportation, storage, and processes undergone by parts such as machining or cleaning are linked to part records. Tracking parts provides a great logistics benefit and an important quality assurance reference during construction. In addition, the location history of parts provides an estimate of their exposure to cosmic radiation. A web application for data entry and a radiation exposure calculator have been developed as tools for achieving the extreme radio-purity required for this rare decay search.

  20. The Majorana Parts Tracking Database

    E-Print Network [OSTI]

    The Majorana Collaboration; N. Abgrall; E. Aguayo; F. T. Avignone III; A. S. Barabash; F. E. Bertrand; V. Brudanin; M. Busch; D. Byram; A. S. Caldwell; Y-D. Chan; C. D. Christofferson; D. C. Combs; C. Cuesta; J. A. Detwiler; P. J. Doe; Yu. Efremenko; V. Egorov; H. Ejiri; S. R. Elliott; J. Esterline; J. E. Fast; P. Finnerty; F. M. Fraenkle; A. Galindo-Uribarri; G. K. Giovanetti; J. Goett; M. P. Green; J. Gruszko; V. E. Guiseppe; K. Gusev; A. L. Hallin; R. Hazama; A. Hegai; R. Henning; E. W. Hoppe; S. Howard; M. A. Howe; K. J. Keeter; M. F. Kidd; O. Kochetov; S. I. Konovalov; R. T. Kouzes; B. D. LaFerriere; J. Diaz Leon; L. E. Leviner; J. C. Loach; J. MacMullin; R. D. Martin; S. J. Meijer; S. Mertens; M. L. Miller; L. Mizouni; M. Nomachi; J. L. Orrell; C. O'Shaughnessy; N. R. Overman; R. Petersburg; D. G. Phillips II; A. W. P. Poon; K. Pushkin; D. C. Radford; J. Rager; K. Rielage; R. G. H. Robertson; E. Romero-Romero; M. C. Ronquest; B. Shanks; T. Shima; M. Shirchenko; K. J. Snavely; N. Snyder; A. Soin; A. M. Suriano; D. Tedeschi; J. Thompson; V. Timkin; W. Tornow; J. E. Trimble; R. L. Varner; S. Vasilyev; K. Vetter; K. Vorren; B. R. White; J. F. Wilkerson; C. Wiseman; W. Xu; E. Yakushev; A. R. Young; C. -H. Yu; V. Yumatov; I. Zhitnikov

    2015-02-05T23:59:59.000Z

    The Majorana Demonstrator is an ultra-low background physics experiment searching for the neutrinoless double beta decay of $^{76}$Ge. The Majorana Parts Tracking Database is used to record the history of components used in the construction of the Demonstrator. The tracking implementation takes a novel approach based on the schema-free database technology CouchDB. Transportation, storage, and processes undergone by parts such as machining or cleaning are linked to part records. Tracking parts provides a great logistics benefit and an important quality assurance reference during construction. In addition, the location history of parts provides an estimate of their exposure to cosmic radiation. A web application for data entry and a radiation exposure calculator have been developed as tools for achieving the extreme radio-purity required for this rare decay search.

  1. Heating the bubbly gas of galaxy clusters with weak shocks and sound waves

    E-Print Network [OSTI]

    S. Heinz; E. Churazov

    2005-09-26T23:59:59.000Z

    Using hydrodynamic simulations and a technique to extract the rotational component of the velocity field, we show how bubbles of relativistic gas inflated by AGN jets in galaxy clusters act as a catalyst, transforming the energy carried by sound and shock waves to heat. The energy is stored in a vortex field around the bubbles which can subsequently be dissipated. The efficiency of this process is set mainly by the fraction of the cluster volume filled by (sub-)kpc scale filaments and bubbles of relativistic plasma.

  2. Oxygen quenching in LAB based liquid scintillator and nitrogen bubbling model

    E-Print Network [OSTI]

    Xiao Hua-Lin

    2009-07-03T23:59:59.000Z

    The oxygen quenching effect in Linear Alkl Benzne (LAB) based liquid scintillator (LAB as the solvent, 3 g/L 2, 5 diphe-nyloxazole (PPO) as the fluor and 15 mg/L $p$-bis-($o$-methylstyryl)-benzene (bis-MSB) as the $\\lambda$-shifter) is studied by measuring the light yield as the function of the nitrogen bubbling time. It is shown that the light yield of the fully purged liquid scintillator is increased by 11% at the room temperature and the room atmosphere pressure. A simple nitrogen bubbling model is proposed to describe the relationship between the relative light yield (oxygen quenching factor) and the bubbling time.

  3. Robotic vehicle with multiple tracked mobility platforms

    DOE Patents [OSTI]

    Salton, Jonathan R. (Albuquerque, NM); Buttz, James H. (Albuquerque, NM); Garretson, Justin (Albuquerque, NM); Hayward, David R. (Wetmore, CO); Hobart, Clinton G. (Albuquerque, NM); Deuel, Jr., Jamieson K. (Albuquerque, NM)

    2012-07-24T23:59:59.000Z

    A robotic vehicle having two or more tracked mobility platforms that are mechanically linked together with a two-dimensional coupling, thereby forming a composite vehicle of increased mobility. The robotic vehicle is operative in hazardous environments and can be capable of semi-submersible operation. The robotic vehicle is capable of remote controlled operation via radio frequency and/or fiber optic communication link to a remote operator control unit. The tracks have a plurality of track-edge scallop cut-outs that allow the tracks to easily grab onto and roll across railroad tracks, especially when crossing the railroad tracks at an oblique angle.

  4. Tracking the Elusive QOOH Radical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003Tool ofTopo II:7.1Tracking Living CellsTracking

  5. Tracking the Elusive QOOH Radical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solidSynthesisAppliances » TopTours SignTracking LivingTracking

  6. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    E-Print Network [OSTI]

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-01-01T23:59:59.000Z

    Analysis for a Heavy Ion Beam Chamber with Plasma Channelsthe target chamber wall, an adiabatic lens to focus the ionchamber that utilizes pre-formed plasma channels for heavy ion

  7. In vivo multi-modality photoacoustic and pulse echo tracking of prostate tumor growth using a window chamber

    E-Print Network [OSTI]

    Witte, Russell S.

    and mortality rates. It is the most commonly diagnosed invasive cancer and a leading cause of death in men with cancer1-4 . The American Cancer Society estimates that in the United States in 2009 over 190,000 cases the disease, making it the second leading cause of death among men in the U.S. Improved detection and early

  8. HOM Sensitivity in the PEP-II HER Vacuum Chamber

    SciTech Connect (OSTI)

    Weathersby, Stephen; Novokhatski, Alexander; Sullivan, Mike; /SLAC

    2010-02-10T23:59:59.000Z

    Synchrotron radiation is the main source of vacuum chamber heating in the PEP-II storage ring collider. This heating is reduced substantially as lattice energy is lowered. Energy scans over {Upsilon} energy states were performed by varying the high energy ring (HER) lattice energy at constant gap voltage and frequency. We observed unexpected temperature rise at particular locations when HER lattice energy was lowered from 8.6 GeV ({Upsilon}(3S)) to 8.0 GeV ({Upsilon}(2S)) while most other temperatures decreased. Bunch length measurements reveal a shorter bunch at the lower energy. The shortened bunch overheated a beam position monitoring electrode causing a vacuum breach. We explain the unexpected heating as a consequence of increased higher order mode (HOM) power generated by a shortened bunch. In this case, temperature rise helps to identify HOM sources and HOM sensitive vacuum chamber elements. Reduction of gap voltage helps to reduce this unexpected heating.

  9. Combustion of Shock-Dispersed Fuels in a Chamber

    SciTech Connect (OSTI)

    Neuwald, P; Reichenbach, H; Kuhl, A L

    2003-04-23T23:59:59.000Z

    In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30 % of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can be looked upon as a natural generalization of this mechanism: a booster charge disperses a (non-explosive) fuel, provides mixing with air and - by means of the hot detonation products - energy to ignite the fuel. The current version of our miniature Shock-Dispersed-Fuel (SDF) charges consists of a spherical booster charge of 0.5 g PETN, embedded in a paper cylinder of approximately 2.2 cm3, which is filled with powdered fuel compositions. The main compositions studied up to now contain aluminum powder, hydrocarbon powders like polyethylene or sucrose and/or carbon particles. These charges were studied in three different chambers of 4-1, 6.6-1 and 40.5-1 volume. In general, the booster charge was sufficient to initiate burning of the fuel. This modifies the pressure signatures measured with a number of wall gages and increases the quasi-static overpressure level obtained in the chambers. On the one hand the time-scale and the yield of the pressure rise depend on the fuel and its characteristics. On the other hand they also depend on the flow dynamics in the chamber, which is dominated by shock reverberations, and thus on the chamber geometry and volume. The paper gives a survey of the experimental results and discusses the possible influences of some basic parameters.

  10. Using sputter coated glass to stabilize microstrip gas chambers

    DOE Patents [OSTI]

    Gong, Wen G. (Albany, CA)

    1997-01-01T23:59:59.000Z

    By sputter coating a thin-layer of low-resistive, electronically-conductive glass on various substrates (including quartz and ceramics, thin-film Pestov glass), microstrip gas chambers (MSGC) of high gain stability, low leakage current, and a high rate capability can be fabricated. This design can make the choice of substrate less important, save the cost of ion-implantation, and use less glass material.

  11. Low Pressure Negative Ion Drift Chamber for Dark Matter Search

    E-Print Network [OSTI]

    D. P. Snowden-Ifft; C. J. Martoff; J. M. Burwell

    1999-04-06T23:59:59.000Z

    Weakly Interacting Massive Particles (WIMPs) are an attractive candidate for the dark matter thought to make up the bulk of the mass of our universe. We explore here the possibility of using a low pressure negative ion drift chamber to search for WIMPs. The innovation of drifting ions, instead of electrons, allows the design of a detector with exceptional sensitivity to, background rejection from, and signature of WIMPs.

  12. Ion Chamber Arrays for the Numi Beam at Fermilab

    E-Print Network [OSTI]

    D. Indurthy; Z. Pavlovic; R. Zwaska; R. Keisler; S. Mendoza; S. Kopp; M. Proga; D. Harris; A. Marchionni; J. Morfin; A. Erwin; H. Ping; C. Velissaris; M. Bishai; M. Diwan; B. Viren; D. Naples; D. Northacker; J. McDonald

    2005-06-26T23:59:59.000Z

    The Neutrinos at the Main Injector (NuMI) beamline will deliver an intense muon neutrino beam by focusing a beam of mesons into a long evacuated decay volume. We have built 4 arrays of ionization chambers to monitor the neutrino beam direction and quality. The arrays are located at 4 stations downstream of the decay volume, and measure the remnant hadron beam and tertiary muons produced along with neutrinos in meson decays.

  13. AGATA - Advanced Gamma Tracking Array

    E-Print Network [OSTI]

    S. Akkoyun; A. Algora; B. Alikhani; F. Ameil; G. de Angelis; L. Arnold; A. Astier; A. Ataç; Y. Aubert; C. Aufranc; A. Austin; S. Aydin; F. Azaiez; S. Badoer; D. L. Balabanski; D. Barrientos; G. Baulieu; R. Baumann; D. Bazzacco; F. A. Beck; T. Beck; P. Bednarczyk; M. Bellato; M. A. Bentley; G. Benzoni; R. Berthier; L. Berti; R. Beunard; G. Lo Bianco; B. Birkenbach; P. G. Bizzeti; A. M. Bizzeti-Sona; F. Le Blanc; J. M. Blasco; N. Blasi; D. Bloor; C. Boiano; M. Borsato; D. Bortolato; A. J. Boston; H. C. Boston; P. Bourgault; P. Boutachkov; A. Bouty; A. Bracco; S. Brambilla; I. P. Brawn; A. Brondi; S. Broussard; B. Bruyneel; D. Bucurescu; I. Burrows; A. Bürger; S. Cabaret; B. Cahan; E. Calore; F. Camera; A. Capsoni; F. Carrió; G. Casati; M. Castoldi; B. Cederwall; J. -L. Cercus; V. Chambert; M. El Chambit; R. Chapman; L. Charles; J. Chavas; E. Clément; P. Cocconi; S. Coelli; P. J. Coleman-Smith; A. Colombo; S. Colosimo; C. Commeaux; D. Conventi; R. J. Cooper; A. Corsi; A. Cortesi; L. Costa; F. C. L. Crespi; J. R. Cresswell; D. M. Cullen; D. Curien; A. Czermak; D. Delbourg; R. Depalo; T. Descombes; P. Désesquelles; P. Detistov; C. Diarra; F. Didierjean; M. R. Dimmock; Q. T. Doan; C. Domingo-Pardo; M. Doncel; F. Dorangeville; N. Dosme; Y. Drouen; G. Duchêne; B. Dulny; J. Eberth; P. Edelbruck; J. Egea; T. Engert; M. N. Erduran; S. Ertürk; C. Fanin; S. Fantinel; E. Farnea; T. Faul; M. Filliger; F. Filmer; Ch. Finck; G. de France; A. Gadea; W. Gast; A. Geraci; J. Gerl; R. Gernhäuser; A. Giannatiempo; A. Giaz; L. Gibelin; A. Givechev; N. Goel; V. González; A. Gottardo; X. Grave; J. Gr?bosz; R. Griffiths; A. N. Grint; P. Gros; L. Guevara; M. Gulmini; A. Görgen; H. T. M. Ha; T. Habermann; L. J. Harkness; H. Harroch; K. Hauschild; C. He; A. Hernández-Prieto; B. Hervieu; H. Hess; T. Hüyük; E. Ince; R. Isocrate; G. Jaworski; A. Johnson; J. Jolie; P. Jones; B. Jonson; P. Joshi; D. S. Judson; A. Jungclaus; M. Kaci; N. Karkour; M. Karolak; A. Ka?ka?; M. Kebbiri; R. S. Kempley; A. Khaplanov; S. Klupp; M. Kogimtzis; I. Kojouharov; A. Korichi; W. Korten; Th. Kröll; R. Krücken; N. Kurz; B. Y. Ky; M. Labiche; X. Lafay; L. Lavergne; I. H. Lazarus; S. Leboutelier; F. Lefebvre; E. Legay; L. Legeard; F. Lelli; S. M. Lenzi; S. Leoni; A. Lermitage; D. Lersch; J. Leske; S. C. Letts; S. Lhenoret; R. M. Lieder; D. Linget; J. Ljungvall; A. Lopez-Martens; A. Lotodé; S. Lunardi; A. Maj; J. van der Marel; Y. Mariette; N. Marginean; R. Marginean; G. Maron; A. R. Mather; W. M?czy?ski; V. Mendéz; P. Medina; B. Melon; R. Menegazzo; D. Mengoni; E. Merchan; L. Mihailescu; C. Michelagnoli; J. Mierzejewski; L. Milechina; B. Million; K. Mitev; P. Molini; D. Montanari; S. Moon; F. Morbiducci; R. Moro; P. S. Morrall; O. Möller; A. Nannini; D. R. Napoli; L. Nelson; M. Nespolo; V. L. Ngo; M. Nicoletto; R. Nicolini; Y. Le Noa; P. J. Nolan; M. Norman; J. Nyberg; A. Obertelli; A. Olariu; R. Orlandi; D. C. Oxley; C. Özben; M. Ozille; C. Oziol; E. Pachoud; M. Palacz; J. Palin; J. Pancin; C. Parisel; P. Pariset; G. Pascovici; R. Peghin; L. Pellegri; A. Perego; S. Perrier; M. Petcu; P. Petkov; C. Petrache; E. Pierre; N. Pietralla; S. Pietri; M. Pignanelli; I. Piqueras; Z. Podolyak; P. Le Pouhalec; J. Pouthas; D. Pugnére; V. F. E. Pucknell; A. Pullia; B. Quintana; R. Raine; G. Rainovski; L. Ramina; G. Rampazzo; G. La Rana; M. Rebeschini; F. Recchia; N. Redon; M. Reese; P. Reiter; P. H. Regan; S. Riboldi; M. Richer; M. Rigato; S. Rigby; G. Ripamonti; A. P. Robinson; J. Robin; J. Roccaz; J. -A. Ropert; B. Rossé; C. Rossi Alvarez; D. Rosso; B. Rubio; D. Rudolph; F. Saillant; E. ?ahin; F. Salomon; M. -D. Salsac; J. Salt; G. Salvato; J. Sampson; E. Sanchis; C. Santos; H. Schaffner; M. Schlarb; D. P. Scraggs; D. Seddon; M. ?enyi?it; M. -H. Sigward; G. Simpson; J. Simpson; M. Slee; J. F. Smith; P. Sona; B. Sowicki; P. Spolaore; C. Stahl; T. Stanios; E. Stefanova; O. Stézowski; J. Strachan; G. Suliman; P. -A. Söderström; J. L. Tain; S. Tanguy; S. Tashenov; Ch. Theisen; J. Thornhill; F. Tomasi; N. Toniolo; R. Touzery; B. Travers; A. Triossi; M. Tripon; K. M. M. Tun-Lanoë; M. Turcato; C. Unsworth; C. A. Ur; J. J. Valiente-Dobon; V. Vandone; E. Vardaci; R. Venturelli; F. Veronese; Ch. Veyssiere; E. Viscione; R. Wadsworth; P. M. Walker; N. Warr; C. Weber; D. Weisshaar; D. Wells; O. Wieland; A. Wiens; G. Wittwer; H. J. Wollersheim; F. Zocca; N. V. Zamfir; M. Zi?bli?ski; A. Zucchiatti

    2012-09-17T23:59:59.000Z

    The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation gamma-ray spectrometer. AGATA is based on the technique of gamma-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a gamma ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realization of gamma-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly-segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterization of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximize its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer.

  14. Progress and critical issues for IFE blanket and chamber research

    SciTech Connect (OSTI)

    Abdou, M.; Kulcinski, G.L.; Latkowski, J.F.; Logan, B.G.; Meier, W.R.; Moir, R.W.; Nobile, A.; Peterson, P.F.; Petti, D.; Schultz, K.R.; Tillack, M.S.

    1999-06-23T23:59:59.000Z

    Advances in high gain target designs for Inertial Fusion Energy (IFE), and the initiation of construction of large megajoule-class laser facilities in the U.S. (National Ignition Facility) and France (Laser-Megajoule) capable of testing the requirements for inertial fusion ignition and propagating burn, have improved the prospects for IFE. Accordingly, there have recently been modest increases in the US fusion research program related to the feasibility of IFE. These research areas include heavy-ion accelerators, Krypton-Fluoride (KrF) gas lasers, diode-pumped, solid-state (DPSSL) lasers, IFE target designs for higher gains, feasibility of low cost IFE target fabrication and accurate injection, and long-lasting IFE fusion chambers and final optics. Since several studies of conceptual IFE power plant and driver designs were completed in 1992-1996 [1-5], U.S. research in the IFE blanket, chamber, and target technology areas has focused on the critical issues relating to the feasibility of IFE concepts towards the goal of achieving economically-competitive and environmentally-attractive fusion energy. This paper discusses the critical issues in these areas, and the approaches taken to address these issues. The U.S. research in these areas, called IFE Chamber and Target Technologies, is coordinated through the Virtual Laboratory for Technology (VLT) formed by the Department of Energy in December 1998.

  15. Dry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition

    E-Print Network [OSTI]

    California at San Diego, University of

    assessment of dry chamber wall based on ion and photon spectra from a new direct-drive target proposed by NRLDry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition Lifetime is a key issue for the IFE dry chamber wall configuration. Past studies, such as SOMBRERO

  16. IMPACT OF BEAM TRANSPORT METHOD ON CHAMBER AND DRIVER DESIGN FOR

    E-Print Network [OSTI]

    IMPACT OF BEAM TRANSPORT METHOD ON CHAMBER AND DRIVER DESIGN FOR HEAVY ION INERTIAL FUSION ENERGY D propagate in thick-liquid-wall, wetted-wall, and dry-wall chambers. KEYWORDS: heavy ion fusion, ion beam transport, reactor chamber design I. INTRODUCTION The U.S. heavy ion fusion ~HIF! program is working toward

  17. September 29, 2008 TOFE08, San Francisco 1 Laser IFE Direct Drive Chamber Concepts with

    E-Print Network [OSTI]

    Raffray, A. René

    ion threat with dry chamber wall · Magnetic intervention as advanced option to reduce or eliminate ion MJ target (~24% of the energy is in ions and ~1% in photons), a large chamber (~10.75 m) is required chamber as baseline and look at options to accommodate ion threat spectra on the armor. - Engineered armor

  18. Characterization and performances of a monitoring ionization chamber dedicated to IBA-universal

    E-Print Network [OSTI]

    an Ionization Chamber in col- laboration with the company IBA (Ion Beam Applications). This monitoring deviceCharacterization and performances of a monitoring ionization chamber dedicated to IBA patented and five IC2/3 chambers were de- Preprint submitted to Elsevier June 28, 2013 in2p3

  19. IFE chamber walls: requirements, design options, and synergy with MFE plasma facing components

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    rights reserved. PACS: 52.40.H Keywords: Internal fusion; Chamber wall material; X-ray deposition; Ion and ion energy deposition while providing the required lifetime. Chamber concepts utilizing both solid injected into the chamber. The driver (laser or heavy ion) beam is focused on the target, compressing

  20. Dry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition

    E-Print Network [OSTI]

    Raffray, A. René

    provided a more detailed assessment of dry chamber wall based on ion and photon spectra from a new direct much faster than the ions and would reach the chamber wall within about 20 ns in the case without protective gas. The ions take longer to reach the chamber wall. As an example, a simple estimate of the ion

  1. CLOUD CHAMBER: A PERFORMANCE INVOLVING REAL TIME TWO-WAY INTERACTION BETWEEN SUBATOMIC RADIOACTIVE

    E-Print Network [OSTI]

    Miranda, Eduardo Reck

    " by the radiation-generated ion patterns in the glass chamber. If John plays in one way the ion particlesCLOUD CHAMBER: A PERFORMANCE INVOLVING REAL TIME TWO-WAY INTERACTION BETWEEN SUBATOMIC RADIOACTIVE, Harwell, Oxford, UK ABSTRACT ,,Cloud Chamber is a live performance created by composer Alexis Kirke

  2. October 27-28, 2004 HAPL meeting, PPPL Overview of the Components of an IFE Chamber

    E-Print Network [OSTI]

    Raffray, A. René

    of MFE design and R&D info) System (including power cycle) Dry wall chamber (armor must accommodate ion Spectra and Chamber Conditions Prior to Each Shot Must Be Well Characterized (UW) · Attenuation of ion 29% 48% Re-radiation Time Scale (µs) 300-700 300-700 Chamber Gas Ion and Photon Attenuation

  3. Dec 12-13, 2006 HAPL meeting, PPPL Advanced Chamber Concept with Magnetic Intervention

    E-Print Network [OSTI]

    Raffray, A. René

    Dec 12-13, 2006 HAPL meeting, PPPL 1 Advanced Chamber Concept with Magnetic Intervention: - Ion; provision of samples for additional testing elsewhere to follow. · Separate ion dump chamber for magnetic-change dry wall or wetted wall chamber to accommodate ions and provide long life. · Have to make sure

  4. IFSA, Kyoto, Japan, September 2001 1 Dry Chamber Wall Thermo-Mechanical Behavior

    E-Print Network [OSTI]

    Raffray, A. René

    assessment of dry chamber wall [6] based on ion and photon spectra from new direct-drive target from NRL [3 for an Example Case Without a Protective Chamber Gas #12;IFSA, Kyoto, Japan, September 2001 8 Photon and Ion Time of Temporal Distribution for Photons and Ions Based on Direct Drive Spectrum and 6.5 m Chamber without

  5. Technique to Collimate Ions in a Hall-Effect Thruster Discharge Chamber

    E-Print Network [OSTI]

    Walker, Mitchell

    Technique to Collimate Ions in a Hall-Effect Thruster Discharge Chamber Kunning G. Xu and Mitchell in the discharge chamber to repel ions away from the wall and focus them toward centerline. The electrodes repel ions with trajectories that intersect the chamber wall, which results in a more collimated ion exhaust

  6. March 21-22, 2006 HAPL meeting, ORNL Status of Chamber and Blanket Effort

    E-Print Network [OSTI]

    Raffray, A. René

    Spectra Spectra in a 10.75 m Chamber #12;March 21-22, 2006 HAPL meeting, ORNL 5 Smoothness of Plot of Ion Plates Estimated for Cone-Shaped Chamber · Duck bill configuration assumed for the equatorial ion dumpMarch 21-22, 2006 HAPL meeting, ORNL 1 Status of Chamber and Blanket Effort A. René Raffray UCSD

  7. MOBILITIES OF POSITIVE IONS IN SOME GAS MIXTURES USED IN PROPORTIONAL AND DRIFT CHAMBERS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    67 MOBILITIES OF POSITIVE IONS IN SOME GAS MIXTURES USED IN PROPORTIONAL AND DRIFT CHAMBERS G proportional chambers or drift chambers with gas mixtures, using isobutane as a quencher. The positive ions, révisé le 11 juin 1976, accepté le 2 septembre 1976) Résumé. 2014 Le coefficient de mobilité des ions

  8. Recent advances in single-chamber fuel-cells: Experiment and modeling , Zongping Shao b

    E-Print Network [OSTI]

    Haile, Sossina M.

    Recent advances in single-chamber fuel-cells: Experiment and modeling Yong Hao a , Zongping Shao b; accepted 6 May 2006 Abstract Single-chamber fuel cells (SCFC) are ones in which the fuel and oxidizer is discussed. © 2006 Elsevier B.V. All rights reserved. Keywords: Solid oxide fuel cell; Single chamber

  9. Bubble behavior in subcooled flow boiling on surfaces of variable wettability

    E-Print Network [OSTI]

    Tow, Emily W

    2012-01-01T23:59:59.000Z

    Flow boiling is important in energy conversion and thermal management due to its potential for very high heat fluxes. By improving understanding of the conditions leading to bubble departure, surfaces can be designed that ...

  10. Heating the intra-cluster medium by jet-inflated bubbles

    E-Print Network [OSTI]

    Hillel, Shlomi

    2015-01-01T23:59:59.000Z

    We examine the heating of the intra-cluster medium (ICM) of cooling flow clusters of galaxies by jet-inflated bubbles and conclude that mixing of hot bubble gas with the ICM is the dominate heating process. We use the PLUTO hydrodynamical code in full 3D to properly account for the inflation of the bubbles and to the multiple vortices induced by the jets and bubbles. The vortices mix some hot shocked jet gas with the ICM. For the parameters used the mixing process accounts for approximately 80% of the energy transferred from the jets to the ICM. Only about 20% of the transferred energy is channelled to the kinetic energy of the ICM. Part of this develops as ICM turbulence. We conclude that turbulent heating plays a smaller role than mixing. Heating by shocks is less efficient even.

  11. EFFECTIVE EQUATIONS FOR SOUND AND VOID WAVE PROPAGATION IN BUBBLY FLUIDS

    E-Print Network [OSTI]

    Smereka, Peter

    ;1850 NIANQING WANG AND PETER SMEREKA calculation of the sound speed agrees with those of previous investigators including nonlinear effects. For review of the literature on acoustic waves in bubbly liquids the reader

  12. Constraining bubble dynamics and mixing with dissolved gases: Implications for productivity measurements by oxygen mass balance

    E-Print Network [OSTI]

    Hamme, Roberta C; Emerson, Steven R

    2006-01-01T23:59:59.000Z

    ux estimates and bubble dynamics. Organic carbon export fromcarbon export estimates for the whole euphotic zone. Both bubblebubble ?uxes would have had a much larger effect. Previous observations of organic carbon

  13. Geek-Up[6.24.11]: The End of Our Solar System is Bubbly

    Broader source: Energy.gov [DOE]

    The Cray XT4 supercomputer at the Lawrence Berkeley National Laboratory’s National Energy Research Scientific Computing Center (NERSC) is helping to explain the froth of apparent "bubbles."

  14. Bubble formation and Kr distribution in Kr-irradiated UO2

    SciTech Connect (OSTI)

    L.F. He; B. Valderrama; A.-R. Hassan; J. Yu; M. Gupta; J. Pakarinen; H.B. Henderson; J. Gan; M.A. Kirk; A.T. Nelson; M.V. Manuel; A. El-Azab; T.R. Allen

    2015-01-01T23:59:59.000Z

    In situ and ex situ transmission electron microscopy observation of small Kr bubbles in both single-crystal and polycrystalline UO2 were conducted to understand the inert gas bubble behavior in oxide nuclear fuel. The bubble size and volume swelling are shown as a weak function of ion dose but strongly depend on the temperature. The Kr bubble formation at room temperature was observed for the first time. The depth profiles of implanted Kr determined by atom probe tomography are in good agreement with the calculated profiles by SRIM, but the measured concentration of Kr is about 1/3 of calculated one. This difference is mainly due to low solubility of Kr in UO2 matrix, which has been confirmed by both density-functional theory calculations and chemical equilibrium analysis.

  15. automised loop-type bubble: Topics by E-print Network

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

    requirement, since we show that the sub-shock dynamic heating in gas bubble cavitation can lead to conditions required to generate intense 100ps light pulses. To wit we...

  16. Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1

    E-Print Network [OSTI]

    Bieniosek, F.M.

    2008-01-01T23:59:59.000Z

    Drift Compression Magnet Chamber Ion Beam Background Plasmaand reheating of the ion source, the target chamber can betarget chamber ports are reserved for ion beam diagnostics

  17. Tracking dynamic regions of texture and shape

    E-Print Network [OSTI]

    Migdal, Joshua N. (Joshua Nicholas), 1979-

    2007-01-01T23:59:59.000Z

    The tracking of visual phenomena is a problem of fundamental importance in computer vision. Tracks are used in many contexts, including object recognition, classification, camera calibration, and scene understanding. ...

  18. Childhood Cancer Tracking Initiative in Massachusetts

    E-Print Network [OSTI]

    Childhood Cancer Tracking Initiative in Massachusetts: Developing a New Electronic Tool Presented (CEH) Massachusetts Department of Public Health (MDPH) #12;Childhood Cancer Tracking Initiative "Develop methods for linking environmental databases with childhood cancer incidence data to identify

  19. Comparison of Current LCD Tracking Options

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Comparison of Current LCD Tracking Options Bruce Schumm Santa Cruz Institute for Particle Physics tracking somewhat more pressed for new S design (pattern recognition, ` resolution) S detector in real

  20. Track 5: Integration of Safety Into Design

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 5: Integration of Safety Into Design

  1. Track 6: Integrating Safety Into Security Operations

    Broader source: Energy.gov [DOE]

    ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 6: Integrating Safety Into Security Operations

  2. Hydrodynamics of bubble columns with application to Fischer-Tropsch synthesis

    E-Print Network [OSTI]

    Raphael, Matheo Lue

    1988-01-01T23:59:59.000Z

    HYDRODYNAMICS OF BUBBLE COLUMNS AYITH APPLICATION TO FISCHER-TROPSCH SYNTHESIS A Thesis by- MATHEO LUE RAPHAEL Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1988 Major Subject: Chemical Engineering HYDRODYNAMICS OF BUBBLE COLUMNS WITH APPLICATION TO FISCHER-TROPSCH SYNTHESIS A Thesis by iAIATHEO LUE RAPHAEL Approved as to style and content by: D. B. Bukur Chairman of Com 'ttee) M. T. za...

  3. Experimental study on bubble collapse phenomena in subcooled water with three-dimensional particle image velocimetry

    E-Print Network [OSTI]

    Yang, Yu-Hsiang

    1998-01-01T23:59:59.000Z

    EXPERIMENTAL STUDY ON BUBBLE COLLAPSE PHENOMENA IN SUBCOOLED WATER WITH THREE-DIMENSIONAL PARTICLE IMAGE VELOCIMETRY A Thesis by YU-HSIANG YANG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1998 Major Subject: Nuclear Engineering EXPERIMENTAL STUDY ON BUBBLE COLLAPSE PHENOMENA IN SUBCOOLED WATER WITH THREE-DIMENSIONAL PARTICLE IMAGE VELOCIMETRY A Thesis by YU-HSIANG YANG Submitted...

  4. MESO-SCALE MODELING OF THE INFLUENCE OF INTERGRANULAR GAS BUBBLES ON EFFECTIVE THERMAL CONDUCTIVITY

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks

    2011-06-01T23:59:59.000Z

    Using a mesoscale modeling approach, we have investigated how intergranular fission gas bubbles, as observed in high-burnup nuclear fuel, modify the effective thermal conductivity in a polycrystalline material. The calculations reveal that intergranular porosity has a significantly higher resistance to heat transfer compared to randomly-distributed porosity. A model is developed to describe this conductivity reduction that considers an effective grain boundary Kapitza resistance as a function of the fractional coverage of grain boundaries by bubbles.

  5. Effect of bubble volume fraction on the shear and extensional rheology of bubbly liquids based on guar gum (a Giesekus fluid) as continuous phase

    E-Print Network [OSTI]

    Torres, M. D.; Hallmark, B.; Wilson, D. I.

    2014-09-16T23:59:59.000Z

    al., 2012). Bubbly liquids are also 57 encountered in nature in the form of magmas (Manga and Loewenberg, 2001; Gonnermann and 58 Manga, 2007) and in other industrial sectors in the form of foamed cement (Ahmed et al., 2009), 59 extracted crude oil... , retarding coalescence and creaming. In 52 the food sector, the bubble phase is usually air and aerated liquid foods are ubiquitous, from 53 beverages to baked products, ice creams, dairy systems and confectionery, e.g. van Aken (2001). 54 Aeration yields...

  6. TRACKING DYNAMIC BOUNDARIES BY EVOLVING Tingting Jiang

    E-Print Network [OSTI]

    Tingting Jiang

    range of applications. An example in image processing is the analysis of image sequences taken might track the boundary of a forest fire. Other applications include tracking spills of oil or poisonous gas, or clouds and weather patterns. In this dissertation, the author describes a new tracking

  7. COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

    SciTech Connect (OSTI)

    Paul Lam; Dimitri Gidaspow

    2001-08-01T23:59:59.000Z

    This project is a collaborative effort between the University of Akron, Illinois Institute of Technology and two industries: UOP and Energy International. The tasks involve the development of transient two and three dimensional computer codes for slurry bubble column reactors, optimization, comparison to data, and measurement of input parameters, such as the viscosity and restitution coefficients. To understand turbulence, measurements were done in the riser with 530 micron glass beads using a PIV technique. This report summarizes the measurements and simulations completed as described in details in the attached paper, ''Computational and Experimental Modeling of Three-Phase Slurry-Bubble Column Reactor.'' The Particle Image Velocimetry method described elsewhere (Gidaspow and Huilin, 1996) was used to measure the axial and tangential velocities of the particles. This method was modified with the use of a rotating colored transparent disk. The velocity distributions obtained with this method shows that the distribution is close to Maxwellian. From the velocity measurements the normal and the shear stresses were computed. Also with the use of the CCD camera a technique was developed to measure the solids volume fraction. The granular temperature profile follows the solids volume fraction profile. As predicted by theory, the granular temperature is highest at the center of the tube. The normal stress in the direction of the flow is approximately 10 times larger than that in the tangential direction. The <{nu}{prime}{sub z}{nu}{prime}{sub z}> is lower at the center where the <{nu}{prime}{sub {theta}}{nu}{prime}{sub {theta}}> is higher at that point. The Reynolds shear stress was small, producing a restitution coefficient near unity. The normal Reynolds stress in the direction of flow is large due to the fact that it is produced by the large gradient of velocity in the direction of flow compared to the small gradient in the {theta} and r directions. The kinetic theory gives values of viscosity that agree with our previous measurements (Gidaspow, Wu and Mostofi, 1999). The values of viscosity obtained from pressure drop minus weight of bed measurements agree at the center of the tube.

  8. Dual chamber system providing simultaneous etch and deposition on opposing substrate sides for growing low defect density epitaxial layers

    DOE Patents [OSTI]

    Kulkarni, Nagraj S. (Knoxville, TN); Kasica, Richard J. (Ashburn, VA) ,

    2011-03-08T23:59:59.000Z

    A dual-chamber reactor can include a housing enclosing a volume having a divider therein, where the divider defines a first chamber and a second chamber. The divider can include a substrate holder that supports at least one substrate and exposes a first side of the substrate to the first chamber and a second side of the substrate to the second chamber. The first chamber can include an inlet for delivering at least one reagent to the first chamber for forming a film on the first side of the substrate, and the second chamber can include a removal device for removing material from the second side of the substrate.

  9. 6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines 1/2www.sciencedaily.com/releases/2012/05/120515104537.htm

    E-Print Network [OSTI]

    Sóbester, András

    6/10/12 The use of acoustic inversion to estimate the bubble size distribution in pipelines 1/2www gas bubbles in pipelines. The ability to measure gas bubbles in pipelines is vital technique for estimating the gas bubble size distribution (BSD) is to send sound waves through the bubble

  10. Radiopurity assessment of the tracking readout for the NEXT double beta decay experiment

    E-Print Network [OSTI]

    V. Álvarez; I. Bandac; A. I. Barrado; A. Bettini; F. I. G. M. Borges; M. Camargo; S. Cárcel; S. Cebrián; A. Cervera; C. A. N. Conde; E. Conde; T. Dafni; J. Díaz; R. Esteve; L. M. P. Fernandes; M. Fernández; P. Ferrario; A. L. Ferreira; E. D. C. Freitas; V. M. Gehman; A. Goldschmidt; H. Gómez; J. J. Gómez-Cadenas; D. González-Díaz; R. M. Gutiérrez; J. Hauptman; J. A. Hernando Morata; D. C. Herrera; F. J. Iguaz; I. G. Irastorza; L. Labarga; A. Laing; I. Liubarsky; D. Lorca; M. Losada; G. Luzón; A. Marí; J. Martín-Albo; A. Martínez; G. Martínez-Lema; T. Miller; F. Monrabal; M. Monserrate; C. M. B. Monteiro; F. J. Mora; L. M. Moutinho; J. Muñoz Vidal; M. Nebot-Guinot; D. Nygren; C. A. B. Oliveira; A. Ortiz de Solórzano; J. Pérez; J. L. Pérez Aparicio; J. Renner; L. Ripoll; A. Rodríguez; J. Rodríguez; F. P. Santos; J. M. F. dos Santos; L. Segui; L. Serra; D. Shuman; A. Simón; C. Sofka; M. Sorel; J. F. Toledo; J. Torrent; Z. Tsamalaidze; J. F. C. A. Veloso; J. A. Villar; R. C. Webb; J. T. White; N. Yahlali

    2014-11-05T23:59:59.000Z

    The 'Neutrino Experiment with a Xenon Time-Projection Chamber' (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds; therefore, an extensive screening and selection process is underway to control the radiopurity levels of the materials to be used in the experimental set-up of NEXT. The detector design combines the measurement of the topological signature of the event for background discrimination with the energy resolution optimization. Separate energy and tracking readout planes are based on different sensors: photomultiplier tubes for calorimetry and silicon multi-pixel photon counters for tracking. The design of a radiopure tracking plane, in direct contact with the gas detector medium, was a challenge since the needed components have typically activities too large for experiments requiring ultra-low background conditions. Here, the radiopurity assessment of tracking readout components based on gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterraneo de Canfranc (Spain) is described. According to the obtained results, radiopure enough printed circuit boards made of kapton and copper and silicon photomultipliers, fulfilling the requirements of an overall background level in that region of at most 8 x 10-4 counts keV-1 kg-1 y-1, have been identified.

  11. Track Finding Efficiency in BaBar

    E-Print Network [OSTI]

    T. Allmendinger; B. Bhuyan; D. N. Brown; H. Choi; S. Christ; R. Covarelli; M. Davier; A. G. Denig; M. Fritsch; A. Hafner; R. Kowalewski; O. Long; A. M. Lutz; M. Martinelli; D. R. Muller; I. M. Nugent; D. Lopes Pegna; M. V. Purohit; E. Prencipe; J. M. Roney; G. Simi; E. P. Solodov; A. V. Telnov; E. Varnes; R. Waldi; W. F. Wang; R. M. White

    2012-07-12T23:59:59.000Z

    We describe several studies to measure the charged track reconstruction efficiency and asymmetry of the BaBar detector. The first two studies measure the tracking efficiency of a charged particle using $\\tau$ and initial state radiation decays. The third uses the $\\tau$ decays to study the asymmetry in tracking, the fourth measures the tracking efficiency for low momentum tracks, and the last measures the reconstruction efficiency of $K_S^0$ particles. The first section also examines the stability of the measurements vs BaBar running periods.

  12. The Accretion Wind Model of the Fermi Bubbles (II): Radiation

    E-Print Network [OSTI]

    Mou, Guobin; Gan, Zhaoming; Sun, Mouyuan

    2015-01-01T23:59:59.000Z

    In a previous work, we have shown that the formation of the Fermi bubbles can be due to the interaction between winds launched from the hot accretion flow in Sgr A* and the interstellar medium (ISM). In that work, we focus only on the morphology. In this paper we continue our study by calculating the gamma-ray radiation. Some cosmic ray protons (CRp) and electrons must be contained in the winds, which are likely formed by physical processes such as magnetic reconnection. We have performed MHD simulations to study the spatial distribution of CRp, considering the advection and diffusion of CRp in the presence of magnetic field. We find that a permeated zone is formed just outside of the contact discontinuity between winds and ISM, where the collisions between CRp and thermal nuclei mainly occur. The decay of neutral pions generated in the collisions, combined with the inverse Compton scattering of background soft photons by the secondary leptons generated in the collisions and primary CR electrons can well expl...

  13. Performance parameters of a liquid filled ionization chamber array

    SciTech Connect (OSTI)

    Poppe, B.; Stelljes, T. S.; Looe, H. K.; Chofor, N. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121, Germany and WG Medical Radiation Physics, Carl von Ossietzky University, Oldenburg 26121 (Germany)] [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121, Germany and WG Medical Radiation Physics, Carl von Ossietzky University, Oldenburg 26121 (Germany); Harder, D. [Prof. em., Medical Physics and Biophysics, Georg August University, Göttingen 37073 (Germany)] [Prof. em., Medical Physics and Biophysics, Georg August University, Göttingen 37073 (Germany); Willborn, K. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121 (Germany)] [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121 (Germany)

    2013-08-15T23:59:59.000Z

    Purpose: In this work, the properties of the two-dimensional liquid filled ionization chamber array Octavius 1000SRS (PTW-Freiburg, Germany) for use in clinical photon-beam dosimetry are investigated.Methods: Measurements were carried out at an Elekta Synergy and Siemens Primus accelerator. For measurements of stability, linearity, and saturation effects of the 1000SRS array a Semiflex 31013 ionization chamber (PTW-Freiburg, Germany) was used as a reference. The effective point of measurement was determined by TPR measurements of the array in comparison with a Roos chamber (type 31004, PTW-Freiburg, Germany). The response of the array with varying field size and depth of measurement was evaluated using a Semiflex 31010 ionization chamber as a reference. Output factor measurements were carried out with a Semiflex 31010 ionization chamber, a diode (type 60012, PTW-Freiburg, Germany), and the detector array under investigation. The dose response function for a single detector of the array was determined by measuring 1 cm wide slit-beam dose profiles and comparing them against diode-measured profiles. Theoretical aspects of the low pass properties and of the sampling frequency of the detector array were evaluated. Dose profiles measured with the array and the diode detector were compared, and an intensity modulated radiation therapy (IMRT) field was verified using the Gamma-Index method and the visualization of line dose profiles.Results: The array showed a short and long term stability better than 0.1% and 0.2%, respectively. Fluctuations in linearity were found to be within ±0.2% for the vendor specified dose range. Saturation effects were found to be similar to those reported in other studies for liquid-filled ionization chambers. The detector's relative response varied with field size and depth of measurement, showing a small energy dependence accounting for maximum signal deviations of ±2.6% from the reference condition for the setup used. The ?-values of the Gaussian dose response function for a single detector of the array were found to be (0.72 ± 0.25) mm at 6 MV and (0.74 ± 0.25) mm at 15 MV and the corresponding low pass cutoff frequencies are 0.22 and 0.21 mm{sup ?1}, respectively. For the inner 5 × 5 cm{sup 2} region and the outer 11 × 11 cm{sup 2} region of the array the Nyquist theorem is fulfilled for maximum sampling frequencies of 0.2 and 0.1 mm{sup ?1}, respectively. An IMRT field verification with a Gamma-Index analysis yielded a passing rate of 95.2% for a 3 mm/3% criterion with a TPS calculation as reference.Conclusions: This study shows the applicability of the Octavius 1000SRS in modern dosimetry. Output factor and dose profile measurements illustrated the applicability of the array in small field and stereotactic dosimetry. The high spatial resolution ensures adequate measurements of dose profiles in regular and intensity modulated photon-beam fields.

  14. Infrared tag and track technique

    DOE Patents [OSTI]

    Partin, Judy K. (Idaho Falls, ID); Stone, Mark L. (Idaho Falls, ID); Slater, John (Albuquerque, NM); Davidson, James R. (Idaho Falls, ID)

    2007-12-04T23:59:59.000Z

    A method of covertly tagging an object for later tracking includes providing a material capable of at least one of being applied to the object and being included in the object, which material includes deuterium; and performing at least one of applying the material to the object and including the material in the object in a manner in which in the appearance of the object is not changed, to the naked eye.

  15. Single nanoparticle tracking spectroscopic microscope

    DOE Patents [OSTI]

    Yang, Haw (Moraga, CA); Cang, Hu (Berkeley, CA); Xu, Cangshan (Berkeley, CA); Wong, Chung M. (San Gabriel, CA)

    2011-07-19T23:59:59.000Z

    A system that can maintain and track the position of a single nanoparticle in three dimensions for a prolonged period has been disclosed. The system allows for continuously imaging the particle to observe any interactions it may have. The system also enables the acquisition of real-time sequential spectroscopic information from the particle. The apparatus holds great promise in performing single molecule spectroscopy and imaging on a non-stationary target.

  16. Enhanced Generic Phase-field Model of Irradiation Materials: Fission Gas Bubble Growth Kinetics in Polycrystalline UO2

    SciTech Connect (OSTI)

    Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert O.; Gao, Fei; Sun, Xin

    2012-05-30T23:59:59.000Z

    Experiments show that inter-granular and intra-granular gas bubbles have different growth kinetics which results in heterogeneous gas bubble microstructures in irradiated nuclear fuels. A science-based model predicting the heterogeneous microstructure evolution kinetics is desired, which enables one to study the effect of thermodynamic and kinetic properties of the system on gas bubble microstructure evolution kinetics and morphology, improve the understanding of the formation mechanisms of heterogeneous gas bubble microstructure, and provide the microstructure to macroscale approaches to study their impact on thermo-mechanical properties such as thermo-conductivity, gas release, volume swelling, and cracking. In our previous report 'Mesoscale Benchmark Demonstration, Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing', we developed a phase-field model to simulate the intra-granular gas bubble evolution in a single crystal during post-irradiation thermal annealing. In this work, we enhanced the model by incorporating thermodynamic and kinetic properties at grain boundaries, which can be obtained from atomistic simulations, to simulate fission gas bubble growth kinetics in polycrystalline UO2 fuels. The model takes into account of gas atom and vacancy diffusion, vacancy trapping and emission at defects, gas atom absorption and resolution at gas bubbles, internal pressure in gas bubbles, elastic interaction between defects and gas bubbles, and the difference of thermodynamic and kinetic properties in matrix and grain boundaries. We applied the model to simulate gas atom segregation at grain boundaries and the effect of interfacial energy and gas mobility on gas bubble morphology and growth kinetics in a bi-crystal UO2 during post-irradiation thermal annealing. The preliminary results demonstrate that the model can produce the equilibrium thermodynamic properties and the morphology of gas bubbles at grain boundaries for given grain boundary properties. More validation of the model capability in polycrystalline is underway.

  17. Comparison of the bubble size distribution in silicate foams using 2-dimensional images and 3-dimensional x-ray microtomography

    SciTech Connect (OSTI)

    Robert, G.; Baker, D.R.; Rivers, M.L.; Allard, E.; Larocque, J. (McGill); (UC)

    2005-02-03T23:59:59.000Z

    Three silicate glasses were hydrated at high pressure and then heated at atmospheric pressure to exsolve the water into bubbles and create foams. The bubble size distribution in these foams was measured by x-ray microtomography on the GSECARS BM-13 beamline at the Advanced Photon Source. The bubble area distributions were measured in two dimensions using the image slices produced from the microtomography and the software ImageJ. The bubble volume distributions were measured from the three-dimensional tomographic images with the BLOB3D software. We found that careful analysis of the microtomography data in both two and three dimensions was necessary to avoid the physically unrealistic, experimental artifact of identifying and counting many small bubbles whose surfaces were not defined by a septum of glass. When this artifact was avoided the foams demonstrated power-law distributions of bubble sizes in both two and three dimensions. Conversion of the power-law exponents for bubble areas measured in two dimensions to exponents for bubble volumes usually agreed with the measured three dimensional volume exponents. Furthermore, the power-law distributions for bubble volumes typically agree with multiple theories of bubble growth, all of which yield an exponent of 1 for the cumulative bubble volume distribution. The measured bubble volume distributions with exponents near 0.3 can be explained by diffusive growth as proposed by other authors, but distributions with exponents near 1.4 remain to be explained and are the subject of continuing research on the effects of water concentration and melt viscosity on foaming behavior.

  18. Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber Clearing Code Effort 1 Progress Report on Chamber Clearing Code

    E-Print Network [OSTI]

    Raffray, A. René

    Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber Clearing Code Effort 1 Progress Livermore November 13-14, 2001 #12;Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber.g. - CFDRC - HEIGHTS - RECON · Code implementation and integration of packages #12;Nov 13-14, 2001 A. R

  19. Micro-chamber filling experiments for validation of macro models with applications in capillary driven microfluidics 

    E-Print Network [OSTI]

    Gauntt, Stephen Byron

    2009-05-15T23:59:59.000Z

    Prediction of bubble formation during filling of microchambers is often critical for determining the efficacy of microfluidic devices in various applications. In this study experimental validation is performed to verify the predictions from a...

  20. Micro-chamber filling experiments for validation of macro models with applications in capillary driven microfluidics

    E-Print Network [OSTI]

    Gauntt, Stephen Byron

    2009-05-15T23:59:59.000Z

    Prediction of bubble formation during filling of microchambers is often critical for determining the efficacy of microfluidic devices in various applications. In this study experimental validation is performed to verify the predictions from a...

  1. Statistics of the electromagnetic response of a chaotic reverberation chamber

    E-Print Network [OSTI]

    J. -B. Gros; U. Kuhl; O. Legrand; F. Mortessagne; O. Picon; E. Richalot

    2014-09-20T23:59:59.000Z

    This article presents a study of the electromagnetic response of a chaotic reverberation chamber (RC) in the presence of losses. By means of simulations and of experiments, the fluctuations in the maxima of the field obtained in a conventional mode-stirred RC are compared with those in a chaotic RC in the neighborhood of the Lowest Useable Frequency (LUF). The present work illustrates that the universal spectral and spatial statistical properties of chaotic RCs allow to meet more adequately the criteria required by the Standard IEC 61000-4-21 to perform tests of electromagnetic compatibility.

  2. Long ion chamber systems for the SLC (Stanford Linear Collider)

    SciTech Connect (OSTI)

    Rolfe, J.; Gearhart, R.; Jacobsen, R.; Jenkins, T.; McComick, D.; Nelson, R.; Reagan, D.; Ross, M.

    1989-03-01T23:59:59.000Z

    A Panofsky Long Ion Chamber (PLIC) is essentially a gas-filled coaxial cable, and has been used to protect the Stanford Linear Accelerator from damage caused by its electron beam, and as a sensitive diagnostic tool. This old technology has been updated and has found renewed use in the SLC. PLIC systems have been installed as beam steering aids in most parts of the SLC and are a part of the system that protects the SLC from damage by errant beams in several places. 5 refs., 3 figs., 1 tab.

  3. Development of the Captive Aerosol Growth and Evolution Chamber System 

    E-Print Network [OSTI]

    Antonietti, Carlos G

    2014-08-28T23:59:59.000Z

    that are alternated between the two using 3-way valves. There are two Teflon ports for gases and a stainless steel port for aerosol injection and withdrawal. The walls of the room are covered with UV-reflective aluminum panels. A 54 kW air conditioning system... W black lights. The walls of the room are covered with reflective aluminum panels. During operation the inlet and outlet flow rates are matched. The University of California at Riverside environmental chamber consists of two ~90 m3 Teflon bags...

  4. Continuous Flow Diffusion Chamber Measurements of IN Concentration

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution And Bylaws |ContactFlow Diffusion Chamber (CFDC)

  5. Santa Fe Chamber of Commerce Business Awards Gala

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiationImplementingnpitcheResearch Briefs TheSanket A. Deshmukh ArgonneSanta Fe Chamber

  6. Inertial fusion energy target injection, tracking, and beam pointing

    SciTech Connect (OSTI)

    Petzoldt, R.W.

    1995-03-07T23:59:59.000Z

    Several cryogenic targets must be injected each second into a reaction chamber. Required target speed is about 100 m/s. Required accuracy of the driver beams on target is a few hundred micrometers. Fuel strength is calculated to allow acceleration in excess of 10,000 m/s{sup 2} if the fuel temperature is less than 17 K. A 0.1 {mu}m thick dual membrane will allow nearly 2,000 m/s{sup 2} acceleration. Acceleration is gradually increased and decreased over a few membrane oscillation periods (a few ms), to avoid added stress from vibrations which could otherwise cause a factor of two decrease in allowed acceleration. Movable shielding allows multiple targets to be in flight toward the reaction chamber at once while minimizing neutron heating of subsequent targets. The use of multiple injectors is recommended for redundancy which increases availability and allows a higher pulse rate. Gas gun, rail gun, induction accelerator, and electrostatic accelerator target injection devices are studied, and compared. A gas gun is the preferred device for indirect-drive targets due to its simplicity and proven reliability. With the gas gun, the amount of gas required for each target (about 10 to 100 mg) is acceptable. A revolver loading mechanism is recommended with a cam operated poppet valve to control the gas flow. Cutting vents near the muzzle of the gas gun barrel is recommended to improve accuracy and aid gas pumping. If a railgun is used, we recommend an externally applied magnetic field to reduce required current by an order of magnitude. Optical target tracking is recommended. Up/down counters are suggested to predict target arrival time. Target steering is shown to be feasible and would avoid the need to actively point the beams. Calculations show that induced tumble from electrostatically steering the target is not excessive.

  7. Final Report: AST-0613577 "Experimental study of magnetic bubble expansion as a model for extragalactic radio lobes"

    SciTech Connect (OSTI)

    Lynn, Alan [University of New Mexico

    2011-02-18T23:59:59.000Z

    Final report for project "Experimental study of magnetic bubble expansion as a model for extragalactic radio lobes" supported by NSF/DOE Joint Program in Basic Plasma Science.

  8. Beam quality conversion factors for parallel-plate ionization chambers in MV photon beams

    SciTech Connect (OSTI)

    Muir, B. R.; McEwen, M. R.; Rogers, D. W. O. [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada); Institute for National Measurement Standards, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2012-03-15T23:59:59.000Z

    Purpose: To investigate the behavior of plane-parallel ion chambers in high-energy photon beams through measurements and Monte Carlo simulations. Methods: Ten plane-parallel ion chamber types were obtained from the major ion chamber manufacturers. Absorbed dose-to-water calibration coefficients are measured for these chambers and k{sub Q} factors are determined. In the process, the behaviors of the chambers are characterized through measurements of leakage currents, chamber settling in cobalt-60, polarity and ion recombination behavior, and long-term stability. Monte Carlo calculations of the absorbed dose to the air in the ion chamber and absorbed dose to water are obtained to calculate k{sub Q} factors. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors are investigated by varying material properties and chamber dimensions. Results: Chamber behavior was variable in MV photon beams, especially with regard to chamber leakage and ion recombination. The plane-parallel chambers did not perform as well as cylindrical chambers. Significant differences up to 1.5% were observed in calibration coefficients after a period of eight months although k{sub Q} factors were consistent on average within 0.17%. Chamber-to-chamber variations in k{sub Q} factors for chambers of the same type were at the 0.2% level. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors ranged between 0.34% and 0.50% depending on the chamber type. Average percent differences between measured and calculated k{sub Q} factors were - 0.02%, 0.18%, and - 0.16% for 6, 10, and 25 MV beams, respectively. Conclusions: Excellent agreement is observed on average at the 0.2% level between measured and Monte Carlo calculated k{sub Q} factors. Measurements indicate that the behavior of these chambers is not adequate for their use for reference dosimetry of high-energy photon beams without a more extensive QA program than currently used for cylindrical reference-class ion chambers.

  9. Shock-Dispersed-Fuel Charges: Combustion in Chambers and Tunnels

    SciTech Connect (OSTI)

    Neuwald, P; Reichenbach, H; Kuhl, A L

    2003-04-22T23:59:59.000Z

    In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30% of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can be looked upon as a natural generalization of this mechanism: a booster charge disperses a (non-explosive) fuel, provides mixing with air and, by means of the hot detonation products, the energy to ignite the fuel. The current version of our miniature Shock-Dispersed-Fuel (SDF) charges consists of a spherical booster charge of 0.5 g PETN, embedded in a paper cylinder of approximately 2.2 cm, which is filled with powdered fuel compositions. The main compositions studied up to now contain aluminum flakes, hydrocarbon powders like polyethylene or hexosen (sucrose) and/or carbon particles. These charges were studied in four different chambers: two cylindrical vessels of 6.6-1 and 40.5-1 volume with a height-to-diameter ratio of approximately 1, a rectangular chamber of 41 (10.5 x 10.5 x 38.6 cm) and a 299.6 cm long tunnel model with a cross section of 8 x 8 cm (volume 19.21) closed at both ends.

  10. Slag monitoring system for combustion chambers of steam boilers

    SciTech Connect (OSTI)

    Taler, J.; Taler, D. [Cracow University of Technology, Krakow (Poland)

    2009-07-01T23:59:59.000Z

    The computer-based boiler performance system presented in this article has been developed to provide a direct and quantitative assessment of furnace and convective surface cleanliness. Temperature, pressure, and flow measurements and gas analysis data are used to perform heat transfer analysis in the boiler furnace and evaporator. Power boiler efficiency is calculated using an indirect method. The on-line calculation of the exit flue gas temperature in a combustion chamber allows for an on-line heat flow rate determination, which is transferred to the boiler evaporator. Based on the energy balance for the boiler evaporator, the superheated steam mass flow rate is calculated taking into the account water flow rate in attemperators. Comparing the calculated and the measured superheated steam mass flow rate, the effectiveness of the combustion chamber water walls is determined in an on-line mode. Soot-blower sequencing can be optimized based on actual cleaning requirements rather than on fixed time cycles contributing to lowering of the medium usage in soot blowers and increasing of the water-wall lifetime.

  11. Atmospheric-pressure plasma decontamination/sterilization chamber

    DOE Patents [OSTI]

    Herrmann, Hans W. (Los Alamos, NM); Selwyn, Gary S. (Los Alamos, NM)

    2001-01-01T23:59:59.000Z

    An atmospheric-pressure plasma decontamination/sterilization chamber is described. The apparatus is useful for decontaminating sensitive equipment and materials, such as electronics, optics and national treasures, which have been contaminated with chemical and/or biological warfare agents, such as anthrax, mustard blistering agent, VX nerve gas, and the like. There is currently no acceptable procedure for decontaminating such equipment. The apparatus may also be used for sterilization in the medical and food industries. Items to be decontaminated or sterilized are supported inside the chamber. Reactive gases containing atomic and metastable oxygen species are generated by an atmospheric-pressure plasma discharge in a He/O.sub.2 mixture and directed into the region of these items resulting in chemical reaction between the reactive species and organic substances. This reaction typically kills and/or neutralizes the contamination without damaging most equipment and materials. The plasma gases are recirculated through a closed-loop system to minimize the loss of helium and the possibility of escape of aerosolized harmful substances.

  12. Finite element solution of Laplace's equation for ion-atom chambers Jacob Golde, Janine Shertzer, and Paul Oxley

    E-Print Network [OSTI]

    Oxley, Paul

    Finite element solution of Laplace's equation for ion-atom chambers Jacob Golde, Janine Shertzer for ion-atom chambers. We first consider a simplified model chamber for which an analytical solution can is carried out in an ion-atom chamber. The atomic beam first passes through a region of the cham- ber where

  13. Simulating the universe(s) II: phenomenology of cosmic bubble collisions in full General Relativity

    E-Print Network [OSTI]

    Carroll L. Wainwright; Matthew C. Johnson; Anthony Aguirre; Hiranya V. Peiris

    2014-07-10T23:59:59.000Z

    Observing the relics of collisions between bubble universes would provide direct evidence for the existence of an eternally inflating Multiverse; the non-observation of such events can also provide important constraints on inflationary physics. Realizing these prospects requires quantitative predictions for observables from the properties of the possible scalar field Lagrangians underlying eternal inflation. Building on previous work, we establish this connection in detail. We perform a fully relativistic numerical study of the phenomenology of bubble collisions in models with a single scalar field, computing the comoving curvature perturbation produced in a wide variety of models. We also construct a set of analytic predictions, allowing us to identify the phenomenologically relevant properties of the scalar field Lagrangian. The agreement between the analytic predictions and numerics in the relevant regions is excellent, and allows us to generalize our results beyond the models we adopt for the numerical studies. Specifically, the signature is completely determined by the spatial profile of the colliding bubble just before the collision, and the de Sitter invariant distance between the bubble centers. The analytic and numerical results support a power-law fit with an index $1< \\kappa \\lesssim 2$. For collisions between identical bubbles, we establish a lower-bound on the observed amplitude of collisions that is set by the present energy density in curvature.

  14. Exploring Light's Interactions with Bubbles and Light Absorbers in Photoelectrochemical Devices using Ray Tracing

    SciTech Connect (OSTI)

    Stevens, John

    2013-12-31T23:59:59.000Z

    Ray tracing was used to perform optical optimization of arrays of photovoltaic microrods and explore the interaction between light and bubbles of oxygen gas on the surface of the microrods. The incident angle of light was varied over a wide range. The percent of incident light absorbed by the microrods and reflected by the bubbles was computed over this range. It was found that, for the 10 ?m diameter, 100 ?m tall SrTiO{sub 3} microrods simulated in the model, the optimal center-­?to-­?center spacing was 14 ?m for a square grid. This geometry produced 75% average and 90% maximum absorbance. For a triangular grid using the same microrods, the optimal center-­?to-­?center spacing was 14 ?m. This geometry produced 67% average and 85% maximum absorbance. For a randomly laid out grid of 5 ?m diameter, 100 ?m tall SrTiO! microrods with an average center-­?to-­?center spacing of 20 ?m, the average absorption was 23% and the maximum absorption was 43%. For a 50% areal coverage fraction of bubbles on the absorber surface, between 2%-­?20% of the incident light energy was reflected away from the rods by the bubbles, depending upon incident angle and bubble morphology.

  15. Thin-shell bubbles and information loss problem in anti de Sitter background

    E-Print Network [OSTI]

    Misao Sasaki; Dong-han Yeom

    2014-12-25T23:59:59.000Z

    We study the motion of thin-shell bubbles and their tunneling in anti de Sitter (AdS) background. We are interested in the case when the outside of a shell is a Schwarzschild-AdS space (false vacuum) and the inside of it is an AdS space with a lower vacuum energy (true vacuum). If a collapsing true vacuum bubble is created, classically it will form a Schwarzschild-AdS black hole. However, this collapsing bubble can tunnel to a bouncing bubble that moves out to spatial infinity. Then, although the classical causal structure of a collapsing true vacuum bubble has the singularity and the event horizon, quantum mechanically the wavefunction has support for a history without any singularity nor event horizon which is mediated by the non-perturbative, quantum tunneling effect. This may be regarded an explicit example that shows the unitarity of an asymptotic observer in AdS, while a classical observer who only follows the most probable history effectively lose information due to the formation of an event horizon.

  16. Formation and Collapse of False Vacuum Bubbles in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Rajarshi Ray; Soma Sanyal; Ajit M. Srivastava

    2002-09-10T23:59:59.000Z

    It is possible that under certain situations, in a relativistic heavy-ion collision, partons may expand out forming a shell like structure. We analyze the process of hadronization in such a picture for the case when the quark-hadron transition is of first order, and argue that the inside region of such a shell must correspond to a supercooled (to $T = 0$) deconfined vacuum. Hadrons from that region escape out, leaving a bubble of pure deconfined vacuum with large vacuum energy. This bubble undergoes relativistic collapse, with highly Lorentz contracted bubble walls, and may concentrate the entire energy into extremely small regions. Eventually different portions of bubble wall collide, with the energy being released in the form of particle production. Thermalization of this system can lead to very high temperatures. With a reasonably conservative set of parameters, at LHC, the temperature of the hot spot can reach as high as 3 GeV, and well above it with more optimistic parameters. Such a hot spot can leave signals like large $P_T$ partons, dileptons, and enhanced production of heavy quarks. We also briefly discuss a speculative possibility where the electroweak symmetry may get restored in the highly dense region resulting from the decay of the bubble wall via the phenomenon of non-thermal symmetry restoration (which is usually employed in models of pre-heating after inflation). If that could happen then the possibility may arise of observing sphaleron induced baryon number violation in relativistic heavy-ion collisions.

  17. Dose response of selected ion chambers in applied homogeneous transverse and longitudinal magnetic fields

    SciTech Connect (OSTI)

    Reynolds, M. [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Departments of Oncology and Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Rathee, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2013-04-15T23:59:59.000Z

    Purpose: The magnetic fields of an integrated MR-Linac system will alter the paths of electrons that produce ions in the ionization chambers. The dose response of selected ion chambers is evaluated in the presence of varying transverse and longitudinal magnetic fields. The investigation is useful in calibration of therapeutic x-ray beams associated with MR-Linac systems. Methods: The Monte Carlo code PENELOPE was used to model the irradiation of NE2571, and PR06C ionization chambers in the presence of a transverse and longitudinal (with respect to the photon beam) magnetic fields of varying magnitude. The long axis of each chamber was simulated both parallel and perpendicular to the incident photon beam for each magnetic field case. The dose deposited in each chamber for each case was compared to the case with zero magnetic field by means of a ratio. The PR06C chamber's response was measured in the presence of a transverse magnetic field with field strengths ranging from 0.0 to 0.2 T to compare to simulated results. Results: The simulations and measured data show that in the presence of a transverse magnetic field there is a considerable dose response (maximum of 11% near 1.0 T in the ion chambers investigated, which depends on the magnitude of magnetic field, and relative orientation of the magnetic field, radiation beam, and ion chamber. Measurements made with the PR06C chamber verify these results in the region of measurement. In contrast, a longitudinal magnetic field produces only a slight increase in dose response (2% at 1.5 T) that rises slowly with increasing magnetic field and is seemingly independent of chamber orientation. Response trends were similar for the two ion chambers and relative orientations considered, but slight variations are present from chamber to chamber. Conclusions: Care must be taken when making ion chamber measurements in a transverse magnetic field. Ion chamber responses vary not only with transverse field strength, but with chamber orientation and type, and can be considerable. Longitudinal magnetic fields influence ion chamber responses relatively little (2% at 1.5 T), and only at field strengths in excess of 1.0 T.

  18. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, Kenneth C. (201 W. California Ave., #401, Sunnyvale, CA 94086)

    1990-01-01T23:59:59.000Z

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion.

  19. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, Kenneth C. (201 W. California Ave. #705, Sunnyvale, CA 94086)

    1992-01-01T23:59:59.000Z

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion.

  20. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, K.C.

    1992-12-08T23:59:59.000Z

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion. 16 figs.

  1. Tracking system for solar collectors

    DOE Patents [OSTI]

    Butler, Barry L. (Golden, CO)

    1984-01-01T23:59:59.000Z

    A tracking system is provided for pivotally mounted spaced-apart solar collectors. A pair of cables is connected to spaced-apart portions of each collector, and a driver displaces the cables, thereby causing the collectors to pivot about their mounting, so as to assume the desired orientation. The collectors may be of the cylindrical type as well as the flat-plate type. Rigid spar-like linkages may be substituted for the cables. Releasable attachments of the cables to the collectors is also described, as is a fine tuning mechanism for precisely aligning each individual collector.

  2. Tracking system for solar collectors

    DOE Patents [OSTI]

    Butler, B.

    1980-10-01T23:59:59.000Z

    A tracking system is provided for pivotally mounted spaced-apart solar collectors. A pair of cables is connected to spaced-apart portions of each collector, and a driver displaces the cables, thereby causing the collectors to pivot about their mounting, so as to assume the desired orientation. The collectors may be of the cylindrical type as well as the flat-plate type. Rigid spar-like linkages may be substituted for the cables. Releasable attachments of the cables to the collectors is also described, as is a fine tuning mechanism for precisely aligning each individual collector.

  3. Tracking the Elusive QOOH Radical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003Tool ofTopo II:7.1Tracking Living Cells

  4. Tracking the Elusive QOOH Radical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003Tool ofTopo II:7.1Tracking Living

  5. Tracking the Elusive QOOH Radical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solidSynthesisAppliances » TopTours SignTracking

  6. Additives That Prevent Or Reverse Cathode Aging In Drift Chambers With Helium-Isobutane Gas

    E-Print Network [OSTI]

    Adam Boyarski

    2001-12-11T23:59:59.000Z

    Noise and Malter breakdown have been studied at high rates in a test chamber having the same cell structure and gas as in the BaBar drift chamber. The chamber was first damaged by exposing it to a high source level at an elevated high voltage, until its operating current at normal voltages was below 0.5nA/cm. Additives such as water or alcohol allowed the damaged chamber to operate at 25 nA/cm, but when the additive was removed the operating point reverted to the original low value. However with 0.02% to 0.05% oxygen or 5% carbon dioxide the chamber could operate at more than 25 nA/cm, and continued to operate at this level even after the additive was removed. This shows for the first time that running with an O2 or CO2 additive at high ionisation levels can cure a damaged chamber from breakdown problems.

  7. Extended Rayleigh model of bubble evolution with material strength compared to detailed dynamic simulations

    SciTech Connect (OSTI)

    Glinsky, M.E.; Amendt, P.A.; Bailey, D.S.; London, R.A.; Rubenchik, A.M. [Lawrence Livermore National Lab., CA (United States); Strauss, M. [Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev

    1997-03-04T23:59:59.000Z

    The validity of an extended Rayleigh model for laser generated bubbles in soft tissue is examined. This model includes surface tension, viscosity, a realistic water equation of state, material strength and failure, stress wave emission, and linear growth of interface instabilities. It is compared to dynamic simulations using LATIS, which include stress wave propagation, water equation of state, material strength and failure, and viscosity. The model and the simulations are compared using 1-D spherical geometry with bubble in center and a 2-D cylindrical geometry of a laser fiber in water with a bubble formed at the end of the fiber. The model executes over 300x faster on computer than the dynamic simulations.

  8. Modeling the influence of bubble pressure on grain boundary separation and fission gas release

    SciTech Connect (OSTI)

    Pritam Chakraborty; Michael R. Tonks; Giovanni Pastore

    2014-09-01T23:59:59.000Z

    Grain boundary (GB) separation as a mechanism for fission gas release (FGR), complementary to gas bubble interlinkage, has been experimentally observed in irradiated light water reactor fuel. However there has been limited effort to develop physics-based models incorporating this mechanism for the analysis of FGR. In this work, a computational study is carried out to investigate GB separation in UO2 fuel under the effect of gas bubble pressure and hydrostatic stress. A non-dimensional stress intensity factor formula is obtained through 2D axisymmetric analyses considering lenticular bubbles and Mode-I crack growth. The obtained functional form can be used in higher length-scale models to estimate the contribution of GB separation to FGR.

  9. INPUT CONSTRAINED ADAPTIVE TRACKING WITH APPLICATIONS TO

    E-Print Network [OSTI]

    Knobloch,Jürgen

    as models in several industries including continuous polymerization reactors, distillation columns tracking ac- curacy, quantified by > 0 set by the designer, is ensured. The adaptive control strategy does

  10. Energy Intensity Baselining and Tracking Guidance

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

    Learn more at betterbuildings.energy.gov Energy Intensity Baselining and Tracking Guidance i Preface The U.S. Department of Energy's (DOE's) Better Buildings, Better Plants Program...

  11. Liquid fuel vaporizer and combustion chamber having an adjustable thermal conductor

    DOE Patents [OSTI]

    Powell, Michael R; Whyatt, Greg A; Howe, Daniel T; Fountain, Matthew S

    2014-03-04T23:59:59.000Z

    The efficiency and effectiveness of apparatuses for vaporizing and combusting liquid fuel can be improved using thermal conductors. For example, an apparatus having a liquid fuel vaporizer and a combustion chamber can be characterized by a thermal conductor that conducts heat from the combustion chamber to the vaporizer. The thermal conductor can be a movable member positioned at an insertion depth within the combustion chamber that corresponds to a rate of heat conduction from the combustion chamber to the vaporizer. The rate of heat conduction can, therefore, be adjusted by positioning the movable member at a different insertion depth.

  12. TEST OF A LIQUID ARGON CHAMBER WITH 20-u m RMS RESOLUTION

    E-Print Network [OSTI]

    Derenzo, S.E.; Kirschbaum, A.R.; Eberhard, P.H.; Ross, R.R.; Sclmitz, F.T.

    2008-01-01T23:59:59.000Z

    electronics to build chambers with spacings of , "'rJ about 40 fJ-m to increase the signal to noise and hence reliability

  13. Creating Small Gas Bubbles in Flowing Mercury Using Turbulence at an Orifice

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Abdou, Ashraf A [ORNL; Paquit, Vincent C [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL

    2010-01-01T23:59:59.000Z

    Pressure waves created in liquid mercury pulsed spallation targets have been shown to create cavitation damage to the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, creating such a population in mercury is difficult due to the high surface tension and particularly the non-wetting behavior of mercury on gas-injection hardware. If the larger injected gas bubbles can be broken down into small bubbles after they are introduced to the flow, then the material interface problem is avoided. Research at the Oak Ridge National Labarotory is underway to develop a technique that has shown potential to provide an adequate population of small-enough bubbles to a flowing spallation target. This technique involves gas injection at an orifice of a geometry that is optimized to the turbulence intensity and pressure distribution of the flow, while avoiding coalescence of gas at injection sites. The most successful geometry thus far can be described as a square-toothed orifice having a 2.5 bar pressure drop in the nominal flow of 12 L/s for one of the target inlet legs. High-speed video and high-resolution photography have been used to quantify the bubble population on the surface of the mercury downstream of the gas injection sight. Also, computational fluid dynamics has been used to optimize the dimensions of the toothed orifice based on a RANS computed mean flow including turbulent energies such that the turbulent dissipation and pressure field are best suited for turbulent break-up of the gas bubbles.

  14. Influence of surfactant solubility on the deformation and breakup of a bubble or capillary jet in a viscous fluid

    E-Print Network [OSTI]

    Young, Yuan N.

    and Center for Applied Mathematics and Statistics, New Jersey Institute of Technology, Newark, New Jersey pinch-off as occurs for a surfactant-free bubble. Insoluble surfactant significantly retards pinch bubble. With soluble surfactant, depending on parameter values, a slender thread forms but can pinch

  15. A one-way coupled, EulerLagrangian simulation of bubble coalescence in a turbulent pipe flow

    E-Print Network [OSTI]

    Mahesh, Krishnan

    modifies the speed of sound in the bubbly mixture, which has implications for marine acoustic signatures. Gas­liquid flow at microgravity conditions ­ I. Dispersed bubble and slug flow. Int. J. Multiphase- ical in many heat transfer problems where liquid water contacting a hot surface boils and the resulting

  16. High-resolution variations in size, number and arrangement of air bubbles in the EPICA DML (Antarctica) ice core

    E-Print Network [OSTI]

    Garbe, Christoph S.

    (Antarctica) ice core Verena BENDEL,1Ã Kai J. UELTZHO¨ FFER,2 Johannes FREITAG,3 Sepp KIPFSTUHL,3 Werner F bubbles in the EPICA Dronning Maud Land (EDML) (Antarctica) ice core, down to the end of the bubble with the palaeo-temperature proxy, dd18 O, and the dust concentration, which means that in Holocene ice

  17. Stable Carbon Isotopic Composition of the Wine and CO2 Bubbles of Sparkling Wines: Detecting C4 Sugar Additions

    E-Print Network [OSTI]

    Ehleringer, Jim

    Stable Carbon Isotopic Composition of the Wine and CO2 Bubbles of Sparkling Wines: Detecting C4 carbon isotopic composition (expressed as 13C) of the wine and of the CO2 bubbles produced during. Carbon isotope ratio analyses were used to estimate the addition of sugar obtained from C4 plants (sugar

  18. Charge-Focusing Readout of Time Projection Chambers

    E-Print Network [OSTI]

    S. J. Ross; M. T. Hedges; I. Jaegle; M. D. Rosen; I. S. Seong; T. N. Thorpe; S. E. Vahsen; J. Yamaoka

    2013-04-02T23:59:59.000Z

    Time projection chambers (TPCs) have found a wide range of applications in particle physics, nuclear physics, and homeland security. For TPCs with high-resolution readout, the readout electronics often dominate the price of the final detector. We have developed a novel method which could be used to build large-scale detectors while limiting the necessary readout area. By focusing the drift charge with static electric fields, we would allow a small area of electronics to be sensitive to particle detection for a much larger detector volume. The resulting cost reduction could be important in areas of research which demand large-scale detectors, including dark matter searches and detection of special nuclear material. We present simulations made using the software package Garfield of a focusing structure to be used with a prototype TPC with pixel readout. This design should enable significant focusing while retaining directional sensitivity to incoming particles. We also present first experimental results and compare them with simulation.

  19. Conceptual Design Report for the Extreme Ecosystems Test Chambers

    SciTech Connect (OSTI)

    C. Barnes; J. Beller; K. Caldwell; K. Croft; R. Cherry; W. Landman

    1998-12-01T23:59:59.000Z

    This conceptual design supports the creation of Extreme Ecosystems Test Chambers, which will replicate deep subsurface and subocean environments characterized by high pressure (2,000 psi) and subfreezing to high temperature (-4 to 300 degrees F) with differing chemical and saturation conditions. The design provides a system to support research and development that includes heat transfer, phase change issues in porous media, microbiology in extreme environments, and carbon sequestration and extraction. The initial system design is based on the research needs to support the commercial production of methane hydrates from subsurface sediments. The design provides for three pressure vessels: a Down Hole Test Vessel, a Vertical Multi-phase Test Vessel, and a Horizontal Multi-phase Test Vessel.

  20. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Kirkby, Jasper

    2001-01-01T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual e...

  1. Simulation of Enhanced-Explosive Devices in Chambers and Tunnels

    SciTech Connect (OSTI)

    Bell, J B; Kuhl, A L; Beckner, V E

    2007-06-05T23:59:59.000Z

    Introduction: Shock-dispersed fuel (SDF) explosives use a small chemical charge to disperse a combustible fuel that burns in the post-detonation environment. The energy released in the combustion process has the potential for generating higher pressures and temperatures than conventional explosives. However, the development of these types of novel explosive systems requires a detailed understanding of all of the modes of energy release. Objective: The objective of this project is develop a simulation capability for predicting explosion and combustion phase of SDF charges and apply that capability to quantifying the behavior of these types of explosives. Methodology: We approximate the dynamics of an SDF charge using high Reynolds number, fast chemistry model that effectively captures the thermodynamic behavior of SDF charges and accurately models the key modes of energy release. The overall computational model is combined with Adaptive Mesh Refinement (AMR) , implemented in a parallel adaptive framework suited to the massively parallel computer systems. Results: We have developed a multiphase version of the model and used it to simulate an SDF charge in which the dispersed fuel is aluminum flakes. Flow visualizations show that the combustion field is turbulent for the chamber and tunnel cases studied. During the 3 milli-seconds of simulation, over 90% of the Al fuel was consumed for the chamber case, while about 40% was consumed in the tunnel case in agreement with Al-SDF experiments. Significance to DoD: DoD has a requirement to develop enhanced energetic materials to support future military systems. The SDF charges described here utilize the combustion mechanism to increase energy per gram of fuel by a factor of 7 to 10 over conventional (detonating) charges, and increase the temperature of the explosion cloud to 2,000-4,000 K (depending on the SDF fuel). Accurate numerical simulation of such SDF explosions allows one to understand the energy release mechanism, and thereby design full-scale systems with greatly improved explosive efficiency.

  2. TANG et al.: DETECTION AND TRACKING OF OCCLUDED PEOPLE 1 Detection and Tracking of Occluded People

    E-Print Network [OSTI]

    with many subjects that partially occlude each other. This limitation is due to the fact that current peopleTANG et al.: DETECTION AND TRACKING OF OCCLUDED PEOPLE 1 Detection and Tracking of Occluded People We consider the problem of detection and tracking of multiple people in crowded street scenes. State

  3. April 6, 2010 Fast Track and Back Track between Master's and Doctoral Programs

    E-Print Network [OSTI]

    Barthelat, Francois

    April 6, 2010 Fast Track and Back Track between Master's and Doctoral Programs Procedures for Graduate Programs and Students "Transfer" from the Master's to Doctoral Program (Fast tracking procedures) Upon recommendation by the program and approval by Graduate and Postdoctoral Studies (GPS

  4. Eye-Tracking: Characteristics and Methods Eye-Tracking: Research Areas and Applications

    E-Print Network [OSTI]

    Richardson, Daniel C.

    1 Part 1 Eye-Tracking: Characteristics and Methods Part 2 Eye-Tracking: Research Areas. & Bowlin, G. (Eds.) [ PREPRINT, FEB 2004. PLEASE DO NOT QUOTE ] #12;2 Eye-Tracking: Characteristics and Methods Introduction Eye movements are arguably the most frequent of all human movements (Bridgeman, 1992

  5. 3D Tracking of Human Locomotion: A Tracking as Recognition Approach Tao Zhao Ram Nevatia

    E-Print Network [OSTI]

    Southern California, University of

    3D Tracking of Human Locomotion: A Tracking as Recognition Approach £ Tao Zhao Ram Nevatia, tracking re- quires knowledge of initial state; this is a difficult problem and a user often specifies it manually. These difficulties call for stronger prior knowledge on the motion being studied and stronger

  6. The effect of bubble growth dynamics on the performance of a gas evolving electrode

    E-Print Network [OSTI]

    Haque, Mohammad Shamsul

    1967-01-01T23:59:59.000Z

    ) studied the growth of electrolytic bubbles on platinum, copper, iron and nickel electrodes of di Ffer- ent diameters at various constant current levels. They used high speed photography and a series of dry cell batteries for a d. c. power source...THE EFFECT OF BUBBLE GRONTH D'rgiAMI CS ON THE PE' FOi&ilANCE OF A GAS EVOLVING ELECTRODE A Thesis By MOHAMMAD SHAMSUL HAgUE Submitted to the Graduate College of the Texas Alg& University in Partial ful fi llment of the requirements...

  7. Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density

    SciTech Connect (OSTI)

    Bake, Muhammad Ali; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hong Xueren [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

    2012-08-15T23:59:59.000Z

    The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  9. Publisher's Note: Thermally Induced Local Failures in Quasi-One-Dimensional Systems: Collapse in Carbon Nanotubes, Necking in Nanowires, and Opening of Bubbles in DNA

    E-Print Network [OSTI]

    in Carbon Nanotubes, Necking in Nanowires, and Opening of Bubbles in DNA [Phys. Rev. Lett. 104, 025503 (2010

  10. Acoustic emission associated with the bursting of a gas bubble at the free surface of a non-newtonian fluid

    E-Print Network [OSTI]

    Thibaut Divoux; Valérie Vidal; Francisco Melo; Jean-Christophe Géminard

    2008-07-01T23:59:59.000Z

    We report experimental measurements of the acoustic emission associated with the bursting of a gas bubble at the free surface of a non-newtonian fluid. On account of the viscoelastic properties of the fluid, the bubble is generally elongated. The associated frequency and duration of the acoustic signal are discussed with regard to the shape of the bubble and successfully accounted for by a simple linear model. The acoustic energy exhibits a high sensitivity to the dynamics of the thin film bursting, which demonstrates that, in practice, it is barely possible to deduce from the acoustic measurements the total amount of energy released by the event. Our experimental findings provide clues for the understanding of the signals from either volcanoes or foams, where one observes respectively, the bursting of giant bubbles at the free surface of lava and bubble bursting avalanches.

  11. To cite this version : Fokoua, Georges and Gabillet, Cline and Colin, Catherine Experimental study of bubble-drag interaction in a Taylor-Couette

    E-Print Network [OSTI]

    Boyer, Edmond

    of bubble-drag interaction in a Taylor-Couette flow. In: 8th International Conference on Multiphase Flow, Jeju Island : Korea, Republic Of (2013)" #12;Experimental study of bubble-drag interaction in a Taylor between the bubbles, the coherent motion and the viscous drag in a Taylor Couette flow, for the outer

  12. Cavitation bubble dynamics in microfluidic gaps of variable height Pedro A. Quinto-Su, Kang Y. Lim, and Claus-Dieter Ohl

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Cavitation bubble dynamics in microfluidic gaps of variable height Pedro A. Quinto-Su, Kang Y. Lim 2009 We study experimentally the dynamics of laser-induced cavitation bubbles created inside a narrow to a semiun- bounded fluid. The cavitation bubbles are created with pulsed laser light at constant laser

  13. DISTRIBUTED EVENT LOCALIZATION AND TRACKING ALGORITHM (DELTA)

    E-Print Network [OSTI]

    Braun, Torsten

    in a distributed event localization and tracking algorithm (DELTA). DELTA is extended with energy-efficient network management, event classification functionality and an energy based source localization. The energy;#12;Abstract Different approaches to do event detection, tracking, localization and classification have been

  14. Differential Kalman Filteringfor Tracking Rayleigh Fading Channels

    E-Print Network [OSTI]

    Gulak, P. Glenn

    Differential Kalman Filteringfor Tracking Rayleigh Fading Channels M. J. Ornidi,S.Gazol;F? G. Gulak in the tracking of a fadingchannel plays an essential role in many wireless receivers. The conventional Kalman implementation. In this paper a new approach is proposed for the implementation of the Kalman filter based

  15. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    DOE Patents [OSTI]

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21T23:59:59.000Z

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  16. Position and orientation tracking system

    DOE Patents [OSTI]

    Burks, B.L.; DePiero, F.W.; Armstrong, G.A.; Jansen, J.F.; Muller, R.C.; Gee, T.F.

    1998-05-05T23:59:59.000Z

    A position and orientation tracking system presents a laser scanning apparatus having two measurement pods, a control station, and a detector array. The measurement pods can be mounted in the dome of a radioactive waste storage silo. Each measurement pod includes dual orthogonal laser scanner subsystems. The first laser scanner subsystem is oriented to emit a first line laser in the pan direction. The second laser scanner is oriented to emit a second line laser in the tilt direction. Both emitted line lasers scan planes across the radioactive waste surface to encounter the detector array mounted on a target robotic vehicle. The angles of incidence of the planes with the detector array are recorded by the control station. Combining measurements describing each of the four planes provides data for a closed form solution of the algebraic transform describing the position and orientation of the target robotic vehicle. 14 figs.

  17. Position and orientation tracking system

    DOE Patents [OSTI]

    Burks, Barry L. (Oak Ridge, TN); DePiero, Fred W. (Knoxville, TN); Armstrong, Gary A. (Oak Ridge, TN); Jansen, John F. (Knoxville, TN); Muller, Richard C. (Oak Ridge, TN); Gee, Timothy F. (Riceville, TN)

    1998-01-01T23:59:59.000Z

    A position and orientation tracking system presents a laser scanning appaus having two measurement pods, a control station, and a detector array. The measurement pods can be mounted in the dome of a radioactive waste storage silo. Each measurement pod includes dual orthogonal laser scanner subsystems. The first laser scanner subsystem is oriented to emit a first line laser in the pan direction. The second laser scanner is oriented to emit a second line laser in the tilt direction. Both emitted line lasers scan planes across the radioactive waste surface to encounter the detector array mounted on a target robotic vehicle. The angles of incidence of the planes with the detector array are recorded by the control station. Combining measurements describing each of the four planes provides data for a closed form solution of the algebraic transform describing the position and orientation of the target robotic vehicle.

  18. GPU COMPUTING FOR PARTICLE TRACKING

    SciTech Connect (OSTI)

    Nishimura, Hiroshi; Song, Kai; Muriki, Krishna; Sun, Changchun; James, Susan; Qin, Yong

    2011-03-25T23:59:59.000Z

    This is a feasibility study of using a modern Graphics Processing Unit (GPU) to parallelize the accelerator particle tracking code. To demonstrate the massive parallelization features provided by GPU computing, a simplified TracyGPU program is developed for dynamic aperture calculation. Performances, issues, and challenges from introducing GPU are also discussed. General purpose Computation on Graphics Processing Units (GPGPU) bring massive parallel computing capabilities to numerical calculation. However, the unique architecture of GPU requires a comprehensive understanding of the hardware and programming model to be able to well optimize existing applications. In the field of accelerator physics, the dynamic aperture calculation of a storage ring, which is often the most time consuming part of the accelerator modeling and simulation, can benefit from GPU due to its embarrassingly parallel feature, which fits well with the GPU programming model. In this paper, we use the Tesla C2050 GPU which consists of 14 multi-processois (MP) with 32 cores on each MP, therefore a total of 448 cores, to host thousands ot threads dynamically. Thread is a logical execution unit of the program on GPU. In the GPU programming model, threads are grouped into a collection of blocks Within each block, multiple threads share the same code, and up to 48 KB of shared memory. Multiple thread blocks form a grid, which is executed as a GPU kernel. A simplified code that is a subset of Tracy++ [2] is developed to demonstrate the possibility of using GPU to speed up the dynamic aperture calculation by having each thread track a particle.

  19. IFE CHAMBER TECHNOLOGY STATUS AND FUTURE CHALLENGES W.R. Meier1

    E-Print Network [OSTI]

    Raffray, A. René

    1 IFE CHAMBER TECHNOLOGY ­ STATUS AND FUTURE CHALLENGES W.R. Meier1 , A.R. Raffrary2 , S.I. Abdel.gov (925) 422-8536 2. University of California, San Diego, CA 3. Georgia Institute of Technology, Atlanta-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry- wall

  20. IFE CHAMBER TECHNOLOGY STATUS AND FUTURE CHALLENGES W.R. Meier1

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    IFE CHAMBER TECHNOLOGY ­ STATUS AND FUTURE CHALLENGES W.R. Meier1 , A.R. Raffray2 , S.I. Abdel.gov (925) 422-8536 2. University of California, San Diego, CA 3. Georgia Institute of Technology, Atlanta-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry- wall

  1. The development and application of advanced analytical methods to commercial ICF reactor chambers. Final report

    SciTech Connect (OSTI)

    Cousseau, P.; Engelstad, R.; Henderson, D.L. [and others

    1997-10-01T23:59:59.000Z

    Progress is summarized in this report for each of the following tasks: (1) multi-dimensional radiation hydrodynamics computer code development; (2) 2D radiation-hydrodynamic code development; (3) ALARA: analytic and Laplacian adaptive radioactivity analysis -- a complete package for analysis of induced activation; (4) structural dynamics modeling of ICF reactor chambers; and (5) analysis of self-consistent target chamber clearing.

  2. Plasma Chamber and APEX Budget Plans for FY 2000 (and FY 2001)

    E-Print Network [OSTI]

    Abdou, Mohamed

    Plasma Chamber and APEX Budget Plans for FY 2000 (and FY 2001) Spokesperson: Mohamed Abdou OFES: Plasma Chamber Spokesperson: M. Abdou Part I: VLT Director's Proposed Budget: $2200K Task Description Plans and Budgets Technology Area: APEX Spokesperson: M. Abdou Part I: VLT Director's Proposed Budget

  3. In situ reduction and evaluation of anode supported single chamber solid oxide fuel cells

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    In situ reduction and evaluation of anode supported single chamber solid oxide fuel cells D.05.118 #12;Abstract Single chamber anode-supported fuel cells are investigated under several methane under methane-to-oxygen ratio (Rmix) of 2. Anode-supported fuel cells are investigated regarding

  4. Combustion in Meso-scale Vortex Chambers Ming-hsun Wu*

    E-Print Network [OSTI]

    Yang, Vigor

    1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A) #12;2 COMBUSTION IN MESO-SCALE VORTEX CHAMBERS Ming-hsun Wu, Yanxing Wang, Vigor Yang and Richard A with the chemical energy varying from 25 to 174W. For the largest combustion volume, hydrogen and hydrocarbons

  5. A simple analytical model to study and control azimuthal instabilities in annular combustion chambers

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A simple analytical model to study and control azimuthal instabilities in annular combustion analytical method to compute the azimuthal modes appearing in annular combustion chambers and help analyzing exper- imental, acoustic and LES (Large Eddy Simulation) data obtained in these combustion chambers

  6. A time dependent solution for the operation of ion chambers in a high ionization background

    E-Print Network [OSTI]

    Christos Velissaris

    2005-01-17T23:59:59.000Z

    We have derived a time dependent solution describing the development of space charge inside an ion chamber subjected to an externally caused ionization rate N. The solution enables the derivation of a formula that the operational parameters of the chamber must satisfy for saturation free operation. This formula contains a correction factor to account for the finite duration of the ionization rate N.

  7. Analytical and numerical studies of heavy ion beam transport in the fusion chamber

    E-Print Network [OSTI]

    Kaganovich, Igor

    Analytical and numerical studies of heavy ion beam transport in the fusion chamber IGOR D to acceptable levels. During ion beam propagation in the chamber, electrons are drawn into the beam, Princeton, New Jersey 08543, USA Abstract The propagation of a high-current finite-length ion charge bunch

  8. Simulation of Gas Dynamic Behavior in Dry-Wall Inertial Fusion Energy Chambers

    E-Print Network [OSTI]

    Tillack, Mark

    . In this work, the code TSUNAMI [2] was used to model chamber gas dynamics for different shapes, sizes of size scaling. Previous- ly, TSUNAMI was used primarily for studying liquid protec- ted chambers which the basic response charac- teristics (with emphasis on the evolution towards a quiescent state

  9. Vapor chambers with jumping-drop liquid return from superhydrophobic condensers

    E-Print Network [OSTI]

    Chen, Chuan-Hua

    Vapor chambers with jumping-drop liquid return from superhydrophobic condensers Jonathan B. Boreyko January 2013 Accepted 28 January 2013 Keywords: Jumping drops Vapor chamber Superhydrophobicity Wick-propelled jumping drops on a superhydrophobic condenser offer a new mechanism to return the working fluid

  10. INVESTIGATION OF A NEW MODEL FOR BUBBLY CAVITATING FLOW Tim Colonius

    E-Print Network [OSTI]

    Colonius, Tim

    account for phase change, liquid compressibility, and heat and mass transfer within the bubble contents [3 of these models, two-way coupled (dynamic) effects of cavitation are considered meaning that the time evolution], but existing phase- and volume-averaging approaches require two fundamental assumptions that limit

  11. Upper Bound for Neutron Emission from Sonoluminescing Bubbles in Deuterated Acetone C. G. Camara,1

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    of the individual ions would be sufficient to generate thermonuclear fusion [2,6]. Experi- mentally, the search dramatically reduces background. Observation of thermonuclear fusion generated by cav- itation in deuterated search for nuclear fusion inside imploding bubbles of degassed deuterated acetone at 0 C driven by a 15

  12. SOLAR UPGRADE OF METHANE USING DRY REFORMING IN DIRECT CONTACT BUBBLE REACTOR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    process of a solar reformer of dry methane reforming was proposed to operate in a temperature range of 600SOLAR UPGRADE OF METHANE USING DRY REFORMING IN DIRECT CONTACT BUBBLE REACTOR Khalid Al-Ali 1 including lower melting point, thermal and chemical stability, acting simultaneously as heat transport

  13. Water-Splitting Photoelectrolysis Reaction Rate via Microscopic Imaging of Evolved Oxygen Bubbles

    E-Print Network [OSTI]

    Atwater, Harry

    manuscript received June 16, 2010. Published July 19, 2010. The production of hydrogen using solar energy electrochemical probe near the surface10 that can even include local illumination through an optical fiber,11 of the gas-evolving reaction rate. Optical microscopy was used to record the bubble growth on single

  14. Wavelet Spatial Energy Spectrums Studies on Drag Reduction by Micro-bubble Injection

    SciTech Connect (OSTI)

    Ling Zhen; Yassin Hassan [Texas A and M University, College Station, Texas 77843 (United States)

    2006-07-01T23:59:59.000Z

    In this study, continuous wavelet transforms and spatial correlation techniques are employed to determine the space-localized wavenumber energy spectrum of the velocity signals in turbulent channel flow. The flow conditions correspond to single phase flow and micro-bubbles injected two phase flow. The wavelet energy spectrums demonstrate that the wavenumber (eddy size) content of the velocity signals is not only space-dependent but also micro-bubbles can impact the eddy size content. Visual observations of the wavelet energy spectrum spatial distribution was realized by using Particle Image Velocimetry (PIV) measurement technique. The two phase flow condition corresponds to a drag reduction of 38.4% with void fraction of 4.9%. The present results provide evidence that micro-bubbles in the boundary layer of a turbulent channel flow can help adjust the eddy size distributions near the wall. This can assist in explaining that micro-bubbles are performing as buffers to keep the energy of fluid particles going in stream-wise direction and reducing the energy of fluid particles going in normal direction. (authors)

  15. LOWFREQUENCY RADIO OBSERVATIONS OF XRAY GHOST BUBBLES A2597: A HISTORY RADIO ACTIVITY THE CORE

    E-Print Network [OSTI]

    Sarazin, Craig

    LOW­FREQUENCY RADIO OBSERVATIONS OF X­RAY GHOST BUBBLES A2597: A HISTORY RADIO ACTIVITY THE CORE T showed ``ghost holes'' X­ray emission west northeast central radio galaxy PKS 2322#123. Previous radio observations detect radio emission coming from interior X­ray holes. present low­frequency observations A2597

  16. Inflating Fat Bubbles in Clusters of Galaxies by Precessing Massive Slow Jets

    E-Print Network [OSTI]

    Assaf Sternberg; Noam Soker

    2008-01-09T23:59:59.000Z

    We conduct hydrodynamical numerical simulations and find that precessing massive slow jets can inflate fat bubbles, i.e., more or less spherical bubbles, that are attached to the center of clusters of galaxies. To inflate a fat bubble the jet should precess fast. The precessing angle $\\theta$ should be large, or change over a large range $ 0 \\le \\theta \\le \\theta_{\\max} \\sim 30-70 ^\\circ$ (depending also on other parameters), where $\\theta=0$ is the symmetry axis. The constraints on the velocity and mass outflow rate are similar to those on wide jets to inflate fat bubbles. The velocity should be $v_j \\sim 10^4 \\kms$, and the mass loss rate of the two jets should be $ 2 \\dot M_j \\simeq 1-50 \\dot M_\\odot \\yr^{-1} $. These results, and our results from a previous paper dealing with slow wide jets, support the claim that a large fraction of the feedback heating in cooling flow clusters and in the processes of galaxy formation is done by slow massive jets.

  17. Helium gas bubble trapped in liquid helium in high magnetic field

    SciTech Connect (OSTI)

    Bai, H., E-mail: bai@magnet.fsu.edu; Hannahs, S. T.; Markiewicz, W. D.; Weijers, H. W. [National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310 (United States)

    2014-03-31T23:59:59.000Z

    High magnetic field magnets are used widely in the area of the condensed matter physics, material science, chemistry, geochemistry, and biology at the National High Magnetic Field Laboratory. New high field magnets of state-of-the-art are being pursued and developed at the lab, such as the current developing 32?T, 32?mm bore fully superconducting magnet. Liquid Helium (LHe) is used as the coolant for superconducting magnets or samples tested in a high magnetic field. When the magnetic field reaches a relatively high value the boil-off helium gas bubble generated by heat losses in the cryostat can be trapped in the LHe bath in the region where BzdBz/dz is less than negative 2100 T{sup 2}/m, instead of floating up to the top of LHe. Then the magnet or sample in the trapped bubble region may lose efficient cooling. In the development of the 32?T magnet, a prototype Yttrium Barium Copper Oxide coil of 6 double pancakes with an inner diameter of 40?mm and an outer diameter of 140?mm was fabricated and tested in a resistive magnet providing a background field of 15?T. The trapped gas bubble was observed in the tests when the prototype coil was ramped up to 7.5?T at a current of 200?A. This letter reports the test results on the trapped gas bubble and the comparison with the analytical results which shows they are in a good agreement.

  18. Under consideration for publication in J. Fluid Mech. 1 Microfluidics with ultrasound-driven bubbles

    E-Print Network [OSTI]

    Marmottant, Philippe

    , viscous attenuation is concentrated in the Stokes oscillatory boundary layer of size (/)1/2 , with the viscosity and the density. In this boundary layer the steady streaming force is compensated by viscous transport. However, viscous forces at the boundary of the bubble together with the nonlinearity

  19. Transport of bubbles in square microchannels Thomas Cubaud and Chih-Ming Ho

    E-Print Network [OSTI]

    Cubaud, Thomas

    for portable microfluidic devices where two-phase flow is involved such as in a microdirect methanol fuel cell- cal, petroleum, and power generation industries (such as nuclear power plants and micro-fuel cellsTransport of bubbles in square microchannels Thomas Cubaud and Chih-Ming Ho Mechanical

  20. Dynamics on the Way to Forming Glass: Bubbles in Space-time David Chandler1

    E-Print Network [OSTI]

    Chandler, David

    Dynamics on the Way to Forming Glass: Bubbles in Space-time David Chandler1 and Juan P. Garrahan2 1 a theoretical perspective of the dynamics of glass forming liquids and the glass tran- sition of trajectory space. This structure emerges from spatial correlations of dynamics that appear in disordered