Sample records for flat column stars

  1. STAR

    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 Scienceand Requirements RecentlyElectronicResourcesjobsJuly throughR E Q U E N C4Safety STAR

  2. Flattening Scientific CCD Imaging Data with a Dome Flat Field System

    E-Print Network [OSTI]

    J. L. Marshall; D. L. DePoy

    2005-10-07T23:59:59.000Z

    We describe the flattening of scientific CCD imaging data using a dome flat field system. The system uses light emitting diodes (LEDs) to illuminate a carefully constructed dome flat field screen. LEDs have several advantages over more traditional illumination sources: they are available in a wide range of output wavelengths, are inexpensive, have a very long source lifetime, and are straightforward to control digitally. The circular dome screen is made of a material with Lambertian scattering properties that efficiently reflects light of a wide range of wavelengths and incident angles. We compare flat fields obtained using this new system with two types of traditionally-constructed flat fields: twilight sky flats and nighttime sky flats. Using photometric standard stars as illumination sources, we test the quality of each flat field by applying it to a set of standard star observations. We find that the dome flat field system produces flat fields that are superior to twilight or nighttime sky flats, particularly for photometric calibration. We note that a ratio of the twilight sky flat to the nighttime sky flat is flat to within the expected uncertainty; but since both of these flat fields are inferior to the dome flat, this common test is not an appropriate metric for testing a flat field. Rather, the only feasible and correct method for determining the appropriateness of a flat field is to use standard stars to measure the reproducibility of known magnitudes across the detector.

  3. Five points on columns

    E-Print Network [OSTI]

    Rockland, Kathleen

    Column,” like “gene,” has both conceptual and linguistic shortcomings. The simple question “what is a column” is not easy to answer and the word itself is not easy to replace. In the present article, I have selected five ...

  4. The circumstellar shell of the post-AGB star HD 56126: the 12C12C/12C13C isotope ratio and 12C16O column density

    E-Print Network [OSTI]

    Eric J. Bakker; David L. Lambert

    1998-04-22T23:59:59.000Z

    We have made the first detection of circumstellar absorption lines of the 12C13C (Phillips) system 1-0 band and the 12C16O first-overtone 2-0 band in the spectrum of the post-AGB star HD56126 (IRAS07134+1005). The rotational temperatures are lower for molecules with a higher permanent dipole moment. Derived relative column densities ratios are 12C12C/12C13C=36+-13, 12C16O/(12C12C+12C13C)=606+-230, and 12C16O/(12C14N+13C14N)=475+-175. The isotopic exchange reaction for 12C12C is too slow to significantly alter the 12C12C/12C13C ratio and the 12C12C to 12C13C ratio a good measure of half the carbon isotope ratio: 12C/13C=2 X 12C12C/12C13C=72+-26. A fit of the 12C12C excitation model of van Dishoeck & Black (1982) to the relative population distribution of 12C12C yields n sigma / I = 3.3 +- 1.0 X 1e-14. At r=1e16cm this translates in n=1.7e7cm-3 and dM/dt=2.5e-4Msol/year.

  5. Distillation Column Flooding Predictor

    SciTech Connect (OSTI)

    George E. Dzyacky

    2010-11-23T23:59:59.000Z

    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid/vapor traffic that produce increased contact area and lead to substantial increases in separation efficiency – which translates to a 10% increase in energy efficiency on a BTU/bbl basis. The Flooding Predictor™ operates on the principle that between five to sixty minutes in advance of a flooding event, certain column variables experience an oscillation, a pre-flood pattern. The pattern recognition system of the Flooding Predictor™ utilizes the mathematical first derivative of certain column variables to identify the column’s pre-flood pattern(s). This pattern is a very brief, highly repeatable, simultaneous movement among the derivative values of certain column variables. While all column variables experience negligible random noise generated from the natural frequency of the process, subtle pre-flood patterns are revealed among sub-sets of the derivative values of column variables as the column approaches its hydraulic limit. The sub-set of column variables that comprise the pre-flood pattern is identified empirically through in a two-step process. First, 2ndpoint’s proprietary off-line analysis tool is used to mine historical data for pre-flood patterns. Second, the column is flood-tested to fine-tune the pattern recognition for commissioning. Then the Flooding Predictor™ is implemented as closed-loop advanced control strategy on the plant’s distributed control system (DCS), thus automating control of the column at its hydraulic limit.

  6. Glass-silicon column

    DOE Patents [OSTI]

    Yu, Conrad M.

    2003-12-30T23:59:59.000Z

    A glass-silicon column that can operate in temperature variations between room temperature and about 450.degree. C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  7. Column Initialization 1 Initializing Distillation Column Models 1

    E-Print Network [OSTI]

    Dundee, University of

    Column Initialization 1 Initializing Distillation Column Models 1 Roger Fletcher \\Lambda with the optimisation of distillation column models by non­ linear programming are considered. The paper presents of the distillation column model. A certain limiting case of the column model is examined, that of infinite reflux

  8. Chameleon stars

    SciTech Connect (OSTI)

    Dzhunushaliev, Vladimir [Institute for Basic Research, Eurasian National University, Astana, 010008 (Kazakhstan); Institute of Physicotechnical Problems and Material Science of the NAS of the Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Folomeev, Vladimir [Institute of Physicotechnical Problems and Material Science of the NAS of the Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Singleton, Douglas [Institute for Basic Research, Eurasian National University, Astana, 010008 (Kazakhstan); Physics Department, CSU Fresno, Fresno, California 93740-8031 (United States)

    2011-10-15T23:59:59.000Z

    We consider a gravitating spherically symmetric configuration consisting of a scalar field nonminimally coupled to ordinary matter in the form of a perfect fluid. For this system we find static, regular, asymptotically flat solutions for both relativistic and nonrelativistic cases. It is shown that the presence of the nonminimal interaction leads to substantial changes both in the radial matter distribution of the star and in the star's total mass. A simple stability test indicates that, for the choice of parameters used in the paper, the solutions are unstable.

  9. Nuclear reactor control column

    SciTech Connect (OSTI)

    Bachovchin, D.M.

    1982-08-10T23:59:59.000Z

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest crosssectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  10. Nuclear reactor control column

    DOE Patents [OSTI]

    Bachovchin, Dennis M. (Plum Borough, PA)

    1982-01-01T23:59:59.000Z

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  11. Ghost condensate model of flat rotation curves

    E-Print Network [OSTI]

    V. V. Kiselev

    2005-07-29T23:59:59.000Z

    An effective action of ghost condensate with higher derivatives creates a source of gravity and mimics a dark matter in spiral galaxies. We present a spherically symmetric static solution of Einstein--Hilbert equations with the ghost condensate at large distances, where flat rotation curves are reproduced in leading order over small ratio of two energy scales characterizing constant temporal and spatial derivatives of ghost field: $\\mu_*^2$ and $\\mu_\\star^2$, respectively, with a hierarchy $\\mu_\\star\\ll \\mu_*$. We assume that a mechanism of hierarchy is provided by a global monopole in the center of galaxy. An estimate based on the solution and observed velocities of rotations in the asymptotic region of flatness, gives $\\mu_*\\sim 10^{19}$ GeV and the monopole scale in a GUT range $\\mu_\\star\\sim 10^{16}$ GeV, while a velocity of rotation $v_0$ is determined by the ratio: $ \\sqrt{2} v_0^2= \\mu_\\star^2/\\mu_*^2$. A critical acceleration is introduced and naturally evaluated of the order of Hubble rate, that represents the Milgrom's acceleration.

  12. Eruption column physics

    SciTech Connect (OSTI)

    Valentine, G.A.

    1997-03-01T23:59:59.000Z

    In this paper the author focuses on the fluid dynamics of large-scale eruption columns. The dynamics of these columns are rooted in multiphase flow phenomena, so a major part of the paper sets up a foundation on that topic that allows one to quickly assess the inherent assumptions made in various theoretical and experimental approaches. The first part is centered on a set of complex differential equations that describe eruption columns, but the focus is on a general understanding of important physical processes rather than on the mathematics. The author discusses briefly the relative merits and weaknesses of different approaches, emphasizing that the largest advances in understanding are made by combining them. He then focuses on dynamics of steady eruption columns and then on transient phenomena. Finally he briefly reviews the effects of varying behavior of the ambient medium through which an eruption column moves. These final sections will emphasize concepts and a qualitative understanding of eruption dynamics. This paper relies on principles of continuum mechanics and transport processes but does not go into detail on the development of those principles. 36 refs., 36 figs., 3 tabs.

  13. Technical Note Engineering Stratigraphic Columns

    E-Print Network [OSTI]

    reference standard stratigraphic columns. EXAMPLES OF PREVIOUS WORK Standard stratigraphic columns typically, color, and sedimentary structures. Standard columns emphasize vertical changes in the rock sequence and ignore soil units. Very little work has been done on the use of strati- graphic columns to portray

  14. Is flat fair?

    SciTech Connect (OSTI)

    Bunzl, Martin

    2010-07-15T23:59:59.000Z

    Dynamic pricing holds out the promise of shifting peak demand as well as reducing overall demand. But it also raises thorny issues of fairness. All practical pricing systems involve tradeoffs between equity and efficiency. I examine the circumstances under which equity ought to be allowed to trump efficiency and whether or not this constitutes a defense of flat pricing. (author)

  15. Kentish Flats Offshore Wind Farm

    E-Print Network [OSTI]

    Firestone, Jeremy

    Kentish Flats Offshore Wind Farm #12;By August 2005 the offshore wind farm at Kentish Flats plateau just outside the main Thames shipping lanes. The Kentish Flats wind farm will comprise 30 of the wind farm could be up to 90 MW. For the benefit of the environment The British Government has set

  16. Optimal Operation of Kaibel Columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    of Kaibel distillation column Loss method Control Structure Design Estimation Our estimation method Dynamic Is it necessary to manipulate RV ? Control of Kaibel distillation column Loss method Control Structure Design distillation column Loss method Control Structure Design Estimation Our estimation method Dynamic compensation

  17. Diesel prices flat

    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 for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management FermiDavidDiesel prices continueU.S.Diesel prices flat The

  18. Diesel prices flat nationally

    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 for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management FermiDavidDiesel prices continueU.S.Diesel prices flat

  19. Flat | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump to:ar-80m.pdfFillmore County,and WildlifeFlash Steam PowerFlat Jump to:

  20. Selected Topics in Column Generation

    E-Print Network [OSTI]

    2002-12-02T23:59:59.000Z

    Dec 2, 2002 ... Page 1. Selected Topics in Column Generation. Marco E. Lübbecke ... is an ever recurring concept in our “selected topics.” OR/MS Subject ...

  1. Flat Oval Spiral Duct Deflection

    E-Print Network [OSTI]

    Daugherty, Matthew

    2014-03-10T23:59:59.000Z

    , because it has less flat surfaces than rectangular duct. Flat oval can be fit in tight places because of its similar aspect ratio to rectangular duct. [23] 2.6 Duct Selection and Application All ducts are required to be sealed, but leakage testing...

  2. Absolute calibration of optical flats

    DOE Patents [OSTI]

    Sommargren, Gary E.

    2005-04-05T23:59:59.000Z

    The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of absolute flatness over the surface of optical flats. Beams exiting the fiber optics in a PSDI have perfect spherical wavefronts. The measurement beam is reflected from the optical flat and passed through an auxiliary optic to then be combined with the reference beam on a CCD. The combined beams include phase errors due to both the optic under test and the auxiliary optic. Standard phase extraction algorithms are used to calculate this combined phase error. The optical flat is then removed from the system and the measurement fiber is moved to recombine the two beams. The newly combined beams include only the phase errors due to the auxiliary optic. When the second phase measurement is subtracted from the first phase measurement, the absolute phase error of the optical flat is obtained.

  3. Self-regenerating column chromatography

    DOE Patents [OSTI]

    Park, W.K.

    1995-05-30T23:59:59.000Z

    The present invention provides a process for treating both cations and anions by using a self-regenerating, multi-ionic exchange resin column system which requires no separate regeneration steps. The process involves alternating ion-exchange chromatography for cations and anions in a multi-ionic exchange column packed with a mixture of cation and anion exchange resins. The multi-ionic mixed-charge resin column works as a multi-function column, capable of independently processing either cationic or anionic exchange, or simultaneously processing both cationic and anionic exchanges. The major advantage offered by the alternating multi-function ion exchange process is the self-regeneration of the resins.

  4. Thermal Analysis for Ion-Exchange Column System

    SciTech Connect (OSTI)

    Lee, Si Y.; King, William D.

    2012-12-20T23:59:59.000Z

    Models have been developed to simulate the thermal characteristics of crystalline silicotitanate ion exchange media fully loaded with radioactive cesium either in a column configuration or distributed within a waste storage tank. This work was conducted to support the design and operation of a waste treatment process focused on treating dissolved, high-sodium salt waste solutions for the removal of specific radionuclides. The ion exchange column will be installed inside a high level waste storage tank at the Savannah River Site. After cesium loading, the ion exchange media may be transferred to the waste tank floor for interim storage. Models were used to predict temperature profiles in these areas of the system where the cesium-loaded media is expected to lead to localized regions of elevated temperature due to radiolytic decay. Normal operating conditions and accident scenarios (including loss of solution flow, inadvertent drainage, and loss of active cooling) were evaluated for the ion exchange column using bounding conditions to establish the design safety basis. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. In-tank modeling results revealed that an idealized hemispherical mound shape leads to the highest tank floor temperatures. In contrast, even large volumes of CST distributed in a flat layer with a cylindrical shape do not result in significant floor heating.

  5. airlift bubble column: Topics by E-print Network

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

    maximum bonding Lebendiker, Mario 73 Column Initialization 1 Initializing Distillation Column Models 1 Mathematics Websites Summary: Column Initialization 1 Initializing...

  6. Half-flat Quantum Hair

    E-Print Network [OSTI]

    Hugo Garcia-Compean; Oscar Loaiza-Brito; Aldo Martinez-Merino; Roberto Santos-Silva

    2013-10-27T23:59:59.000Z

    By wrapping D3-branes over 3-cycles on a half-flat manifold we construct an effective supersymmetric black hole in the N=2 low-energy theory in four-dimensions. Specifically we find that the torsion cycles present in a half-flat compactification, corresponding to the mirror symmetric image of electric NS flux on a Calabi-Yau manifold, manifest in the half-flat black hole as quantum hair. We compute the electric and magnetic charges related to the quantum hair, and also the mass contribution to the effective black hole. We find that by wrapping a number of D3-branes equal to the order of the discrete group associated to the torsional part of the half-flat homology, the effective charge and mass terms vanishes. We compute the variation of entropy and the corresponding temperature associated with the lost of quantum hair. We also comment on the equivalence between canceling Freed-Witten anomaly and the assumption of self-duality for the 5-form field strength. Finally from a K-theoretical perspective, we compute the presence of discrete RR charge of D-branes wrapping torsional cycles in a half-flat manifold.

  7. SHEPHERDS FLAT | Department of Energy

    Office of Environmental Management (EM)

    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 for4,645 3,625 1,006 492 742 33 1112011 Strategic2 OPAM615_CostNSARDevelopmental Assignment |SHEPHERDS FLAT SHEPHERDS FLAT

  8. Reidemeister torsion for flat superconnections

    E-Print Network [OSTI]

    Abad, Camilo Arias

    2011-01-01T23:59:59.000Z

    We use higher parallel transport -- more precisely, the integration A_{infty}-functor constructed by Block-Smith and Arias Abad-Schaetz -- to define Reidemeister torsion for flat superconnections. We hope that the combinatorial Reidemeister torsion coincides with the analytic torsion defined by Mathai and Wu, thus permitting for a generalization of the Cheeger-Mueller Theorem.

  9. WASTEWATER TREATMENT OVER SAND COLUMNS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the biological mechanisms responsible for wastewater treatment. The first part of the study, conducted on site93/0096 WASTEWATER TREATMENT OVER SAND COLUMNS TREATMENT YIELDS, LOCALISATION OF THE BIOMASS Domestic wastewater treatment by infiltration-percolation is a process that becomming common in France

  10. Graphene folding on flat substrates

    SciTech Connect (OSTI)

    Chen, Xiaoming; Zhao, Yadong; Ke, Changhong, E-mail: cke@binghamton.edu [Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, New York 13902 (United States); Zhang, Liuyang; Wang, Xianqiao [College of Engineering, University of Georgia, Athens, Georgia 30602 (United States)

    2014-10-28T23:59:59.000Z

    We present a combined experimental-theoretical study of graphene folding on flat substrates. The structure and deformation of the folded graphene sheet are experimentally characterized by atomic force microscopy. The local graphene folding behaviors are interpreted based on nonlinear continuum mechanics modeling and molecular dynamics simulations. Our study on self-folding of a trilayer graphene sheet reports a bending stiffness of about 6.57?eV, which is about four times the reported values for monolayer graphene. Our results reveal that an intriguing free sliding phenomenon occurs at the interlayer van der Waals interfaces during the graphene folding process. This work demonstrates that it is a plausible venue to quantify the bending stiffness of graphene based on its self-folding conformation on flat substrates. The findings reported in this work are useful to a better understanding of the mechanical properties of graphene and in the pursuit of its applications.

  11. All conformally flat pure radiation metrics

    E-Print Network [OSTI]

    S. Brian Edgar; Garry Ludwig

    1996-12-20T23:59:59.000Z

    The complete class of conformally flat, pure radiation metrics is given, generalising the metric recently given by Wils.

  12. Evolution of column density distributions within Orion~A

    E-Print Network [OSTI]

    Stutz, A M

    2015-01-01T23:59:59.000Z

    We compare the structure of star-forming molecular clouds in different regions of Orion A to determine how the column density probability distribution function (N-PDF) varies with environmental conditions such as the fraction of young protostars. A correlation between the N-PDF slope and Class 0 protostar fraction has been previously observed in a low-mass star-formation region (Perseus) by Sadavoy; here we test if a similar correlation is observed in a high-mass star-forming region. We use Herschel data to derive a column density map of Orion A. We use the Herschel Orion Protostar Survey catalog for accurate identification and classification of the Orion A young stellar object (YSO) content, including the short-lived Class 0 protostars (with a $\\sim$ 0.14 Myr lifetime). We divide Orion A into eight independent 13.5 pc$^2$ regions; in each region we fit the N-PDF distribution with a power-law, and we measure the fraction of Class 0 protostars. We use a maximum likelihood method to measure the N-PDF power-law ...

  13. The Nature of Flat-Spectrum Nuclear Radio Emission in Seyfert Galaxies

    E-Print Network [OSTI]

    C. G. Mundell; A. S. Wilson; J. S. Ulvestad; A. L. Roy

    2000-12-11T23:59:59.000Z

    Parsec-scale VLBA imaging of five Seyfert galaxies with flat-spectrum radio nuclei was conducted to determine whether the flat spectrum represents thermal emission from the accretion disk/obscuring torus or nonthermal, synchrotron self-absorbed emission. Four of the five show emission consistent with synchrotron self-absorption, with intrinsic sizes ~0.05-0.2 pc (or 10^4 gravitational radii for a 10^8 Msun black hole for the smallest). In contrast, NGC 4388, which was detected with MERLIN but not the VLBA, shows thermal emission with similar properties to that detected in NGC 1068. It is notable that the two Seyfert galaxies with detected thermal nuclear radio emission both have large X-ray absorbing columns, suggesting that columns in excess of \\~10^{24} cm^{-2} are needed for such disks to be detectable.

  14. Intelligent fuzzy supervisory control for distillation columns

    E-Print Network [OSTI]

    Santhanam, Srinivasan

    1993-01-01T23:59:59.000Z

    problem. Multivariable design techniques are used to control the column. Some of the different multivariable techniques which have been used in the distillation column control include decoupling control, optimal control and internal model control [5...

  15. Vectren Energy Delivery of Ohio (Gas)- Energy Star Home Rebate

    Broader source: Energy.gov [DOE]

    Vectren Energy Delivery of Ohio offers a flat rebate to builders of residential single-family Energy Star certified homes that receive gas service from the company. In order to qualify, homes must...

  16. Temperature programmable microfabricated gas chromatography column

    DOE Patents [OSTI]

    Manginell, Ronald P.; Frye-Mason, Gregory C.

    2003-12-23T23:59:59.000Z

    A temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by the integration of a resistive heating element and temperature sensing on the microfabricated column. Additionally, means are provided to thermally isolate the heated column from their surroundings. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  17. Process Svstems Enaineerina Instability of Distillation Columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Process Svstems Enaineerina , Instability of Distillation Columns Elling W. Jacobsen and Sigurd recognized, distillation columns, operating with reflux and boilup as independent inputs, may have The dynamic behavior of distillation columns has been stud- ied quite extensively over the past decades

  18. EXPERIMENTAL SIMULATION OF DISTILLATION COLUMN PROFILE MAPS

    E-Print Network [OSTI]

    Skogestad, Sigurd

    EXPERIMENTAL SIMULATION OF DISTILLATION COLUMN PROFILE MAPS Tshepo Sehole David Modise A thesis or in combination, such as distillation, extraction, crystallization, ect. Among these, distillation is by far profiles for the preliminary design of distillation columns. Residue curves and column profile are not only

  19. Windy Flats | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat 1 Wind Project Jump to:WilsonIIa extension Jump to:Flats Jump

  20. Galactic interstellar abundance surveys with IUE. II. The equivalent widths and column densities

    SciTech Connect (OSTI)

    Van Steenberg, M.E.; Shull, J.M.

    1988-06-01T23:59:59.000Z

    This paper continues a survey of interstellar densities, abundances, and cloud structure in the Galaxy, using the International Ultraviolet Explorer (IUE) satellite. Equivalent widths of 18 ultraviolet resonance transitions are presented and column densities for Si II, Mn II, Fe II, S II, and Zn II toward 261 early-type stars are derived. These equivalent widths and column densities agree within the stated errors of earlier Copernicus, BUSS, or IUE surveys of Mn II, Fe II, S II, and Zn II for 45 stars in common. The column densities are derived from single-component curves of growth with a common b-value based on that of Fe II and Si II. 63 references.

  1. THERMAL MODELING ANALYSIS OF CST MEDIA IN THE SMALL COLUMN ION EXCHANGE PROJECT

    SciTech Connect (OSTI)

    Lee, S.

    2010-11-01T23:59:59.000Z

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. One salt processing scenario includes the transport of the loaded (and possibly ground) CST media to the treatment tank floor. Therefore, additional thermal modeling calculations were conducted using a three-dimensional approach to evaluate temperature distributions for the entire in-tank domain including distribution of the spent CST media either as a mound or a flat layer on the tank floor. These calculations included mixtures of CST with HLW sludge or loaded Monosodium Titanate (MST) media used for strontium/actinide sorption. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed (a primary heat transfer mechanism), inadvertent column drainage, and loss of active cooling in the column. The calculation results showed that for a wet CST column with active cooling through one central and four outer tubes and 35 C ambient external air, the peak temperature for the fully-loaded column is about 63 C under the loss of fluid flow accident, which is well below the supernate boiling point. The peak temperature for the naturally-cooled (no active, engineered cooling) wet column is 156 C under fully-loaded conditions, exceeding the 130 C boiling point. Under these conditions, supernate boiling would maintain the column temperature near 130 C until all supernate was vaporized. Without active engineered cooling and assuming a dry column suspended in unventilated air at 35 C, the fully-loaded column is expected to rise to a maximum of about 258 C due to the combined loss-of coolant and column drainage accidents. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. Results for the in-tank modeling calculations clearly indicate that when realistic heat transfer boundary conditions are imposed on the bottom surface of the tank wall, as much as 450 gallons of ground CST (a volume equivalent to two ion exchange processing cycles) in an ideal hemispherical shape (the most conservative geometry) can be placed in the tank without exceeding the 100 C wall temperature limit. Furthermore, in the case of an evenly-distributed flat layer, the tank wall reaches the temperature limit after the ground CST material reaches a height of approximately 8 inches.

  2. Rocky Flats Environmental Technology Site Archived Soil & Groundwater...

    Office of Environmental Management (EM)

    - Industrial Area Rocky Flats Environmental Technology Site - Mound Plume Rocky Flats Environmental Technology Site - Solar Ponds More Documents & Publications Miamisburg...

  3. ARM - Measurement - Column Ozone Abundance

    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 for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particle ARM DatagovMeasurementsColumn

  4. Natural star-products on symplectic manifolds and related quantum mechanical operators

    SciTech Connect (OSTI)

    B?aszak, Maciej, E-mail: blaszakm@amu.edu.pl; Doma?ski, Ziemowit, E-mail: ziemowit@amu.edu.pl

    2014-05-15T23:59:59.000Z

    In this paper is considered a problem of defining natural star-products on symplectic manifolds, admissible for quantization of classical Hamiltonian systems. First, a construction of a star-product on a cotangent bundle to an Euclidean configuration space is given with the use of a sequence of pair-wise commuting vector fields. The connection with a covariant representation of such a star-product is also presented. Then, an extension of the construction to symplectic manifolds over flat and non-flat pseudo-Riemannian configuration spaces is discussed. Finally, a coordinate free construction of related quantum mechanical operators from Hilbert space over respective configuration space is presented. -- Highlights: •Invariant representations of natural star-products on symplectic manifolds are considered. •Star-products induced by flat and non-flat connections are investigated. •Operator representations in Hilbert space of considered star-algebras are constructed.

  5. Caithness Shepherds Flat | Department of Energy

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

    Flat, which commenced operations in September 2012, is one of the world's largest wind farms. Technology The DOE guarantee was issued under the Financial Institution...

  6. Sandia National Laboratories: Floating Oscillating Water Column

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

    This model has ... Joint Sandia-DOE-HMRC Testing of a Floating Oscillating Water Column Wave Energy Converter Device On November 11, 2013, in Energy, News, News & Events,...

  7. Turkey Flat Site Effects Test Area The Turkey-Flat strong motion "blind"

    E-Print Network [OSTI]

    Oprsal, Ivo

    Turkey Flat Site Effects Test Area B B' A A' C C' The Turkey-Flat strong motion "blind" prediction experiment "Blind" Test Approach · Conduct high quality field and laboratory tests to characterize Geological Survey Turkey Flat, USA Site Effects Test Area: "Blind" Test of Predicted Ground Response

  8. Bosonic condensation in a flat energy band

    E-Print Network [OSTI]

    Baboux, F; Jacqmin, T; Biondi, M; Lemaître, A; Gratiet, L Le; Sagnes, I; Schmidt, S; Türeci, H E; Amo, A; Bloch, J

    2015-01-01T23:59:59.000Z

    Flat bands are non-dispersive energy bands made of fully degenerate quantum states. Such bands are expected to support emergent phenomena with extraordinary spatial and temporal structures, as they strongly enhance the effect of any perturbation induced by disorder, dissipation or interactions. However, flat bands usually appear at energies above the ground state, preventing their study in systems in thermodynamic equilibrium. Here we use cavity polaritons to circumvent this issue. We engineer a flat band in a frustrated lattice of micro-pillar optical cavities. By taking advantage of the non-hermiticity of our system, we achieve for the first time bosonic condensation in a flat band. This allows revealing the peculiar effect of disorder in such band: The condensate fragments into highly localized modes, reflecting the elementary eigenstates produced by geometric frustration. This non-hermitian engineering of a bosonic flat band condensate offers a novel approach to studying coherent phases of light and matte...

  9. Column Asymmetric Catalysis for -Lactam Synthesis

    E-Print Network [OSTI]

    Lectka, Thomas

    Column Asymmetric Catalysis for -Lactam Synthesis Ahmed M. Hafez, Andrew E. Taggi, Harald Wack that constitute the packing of a series of "reaction columns". This process was applied to the catalytic- and diastereoselectivity. In the realm of chiral synthesis and drug discovery, asym- metric catalysis1 and solid

  10. Measurement uncertainty in surface flatness measurement

    E-Print Network [OSTI]

    H. L. Thang

    2011-11-29T23:59:59.000Z

    Flatness of a plate is a parameter has been put under consideration for long time. Factors influencing the accuracy of this parameter have been recognized and examined carefully but placed scatterringly. Beside that those reports have not been always in harmonization with Guide for expression of uncertainty measurement (GUM). Furthermore, mathematical equations describing clearly the flatness measurement have not been seen in those reports also. We have collected those influencing factors for systematic reference purpose, re-written the equation describing the profile measurement of the plate topography, and proposed an equation for flatness determination. An illustrative numerical example will be also shown.

  11. A class of conformally flat solutions for systems undergoing radiative gravitational collapse

    E-Print Network [OSTI]

    Sharma, Ranjan; Tikekar, Ramesh

    2015-01-01T23:59:59.000Z

    We present a class of conformally flat solutions of the Einstein's field equations for spherical systems undergoing gravitational collapse accompanied with radial heat flux. The interior space-time of the collapsing matter is chosen to be conformal to the Robertson-Walker space-time so that its Weyl tensor vanishes identically. The conditions which ensure smooth matching of the interior space-time of the collapsing system, across its boundary, with the exterior space-time of a radiating star which is described by Vaidya metric lead to an equation governing its overall subsequent evolution. New solutions of this equation have been shown to provide physically viable models of collapsing stars.

  12. A class of conformally flat solutions for systems undergoing radiative gravitational collapse

    E-Print Network [OSTI]

    Ranjan Sharma; Shyam Das; Ramesh Tikekar

    2015-02-08T23:59:59.000Z

    We present a class of conformally flat solutions of the Einstein's field equations for spherical systems undergoing gravitational collapse accompanied with radial heat flux. The interior space-time of the collapsing matter is chosen to be conformal to the Robertson-Walker space-time so that its Weyl tensor vanishes identically. The conditions which ensure smooth matching of the interior space-time of the collapsing system, across its boundary, with the exterior space-time of a radiating star which is described by Vaidya metric lead to an equation governing its overall subsequent evolution. New solutions of this equation have been shown to provide physically viable models of collapsing stars.

  13. AdS/Ricci-flat correspondence

    E-Print Network [OSTI]

    Marco M. Caldarelli; Joan Camps; Blaise Goutéraux; Kostas Skenderis

    2014-04-18T23:59:59.000Z

    We present a comprehensive analysis of the AdS/Ricci-flat correspondence, a map between a class of asymptotically locally AdS spacetimes and a class of Ricci-flat spacetimes. We provide a detailed derivation of the map, discuss a number of extensions and apply it to a number of important examples, such as AdS on a torus, AdS black branes and fluids/gravity metrics. In particular, the correspondence links the hydrodynamic regime of asymptotically flat black $p$-branes or the Rindler fluid with that of AdS. It implies that this class of Ricci-flat spacetimes inherits from AdS a generalized conformal symmetry and has a holographic structure. We initiate the discussion of holography by analyzing how the map acts on boundary conditions and holographic 2-point functions.

  14. LM Records Handling System (LMRHS01) - Rocky Flats Environmental...

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

    Rocky Flats Environmental Records Database, Office of Legacy Management LM Records Handling System (LMRHS01) - Rocky Flats Environmental Records Database, Office of Legacy...

  15. PRTR ion exchange vault column sampling

    SciTech Connect (OSTI)

    Cornwell, B.C.

    1995-03-14T23:59:59.000Z

    This report documents ion exchange column sampling and Non Destructive Assay (NDA) results from activities in 1994, for the Plutonium Recycle Test Reactor (PRTR) ion exchange vault. The objective was to obtain sufficient information to prepare disposal documentation for the ion exchange columns found in the PRTR Ion exchange vault. This activity also allowed for the monitoring of the liquid level in the lower vault. The sampling activity contained five separate activities: (1) Sampling an ion exchange column and analyzing the ion exchange media for purpose of waste disposal; (2) Gamma and neutron NDA testing on ion exchange columns located in the upper vault; (3) Lower vault liquid level measurement; (4) Radiological survey of the upper vault; and (5) Secure the vault pending waste disposal.

  16. 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 ...

  17. Heat Exchanger Technologies for Distillation Columns

    E-Print Network [OSTI]

    Polley, G. T.

    Heat Exchanger Technologies for Distillation Columns G.T.Polley Pinchtechnology.com In this paper we look at the challenges that improvements in energy efficiency of distillation systems presents the heat exchanger designer. We examine... condensate sub-cooling. So, if this condensate subsequently requires re-heating both energy and capital have been wasted. If the condensate forms a feed to another distillation column it results in increased energy consumption if that separation...

  18. Performance of Reinforced Concrete Column Lap Splices

    E-Print Network [OSTI]

    Alberson, Ryan M.

    2010-01-14T23:59:59.000Z

    PERFORMANCE OF REINFORCED CONCRETE COLUMN LAP SPLICES A Thesis by RYAN ALBERSON 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 2009 Major Subject: Civil Engineering PERFORMANCE OF REINFORCED CONCRETE COLUMN LAP SPLICES A Thesis by RYAN ALBERSON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

  19. Integrated Thermal and Hydraulic Analysis of Distillation Columns

    E-Print Network [OSTI]

    Samant, K.; Sinclair, I.; Keady, G.

    . The paper outlines how bringing together the column thermal and hydraulics analysis provides significant additional insights to help screen the options for distillation column revamps....

  20. affinity column mediated: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 323 Active constraint...

  1. affinity chromatography columns: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 353 Active constraint...

  2. absorbing column densities: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 485 Active constraint...

  3. antigen-specific immunoadsorption columns: Topics by E-print...

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 78 Active constraint...

  4. activated charcoal column: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 153 Development...

  5. alumina column purification: Topics by E-print Network

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

    Purification Columns. Open Access Theses and Dissertations Summary: ??High-purity distillation columns are highly nonlinear systems. Nonlinear Model Predictive Control of these...

  6. absorbent microcapsules column: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 289 Active constraint...

  7. axisymmetric plasma columns: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 419 Active constraint...

  8. anaerobic aquifer column: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 198 Active constraint...

  9. anion exchange column: Topics by E-print Network

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

    a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared Skogestad, Sigurd 148 Active constraint...

  10. Rocky Flats Compliance Program; Technology summary

    SciTech Connect (OSTI)

    NONE

    1994-02-01T23:59:59.000Z

    The Department of Energy (DOE) established the Office of Technology Development (EM-50) (OTD) as an element of Environmental Restoration and Waste Management (EM) in November 1989. The primary objective of the Office of Technology Development, Rocky Flats Compliance Program (RFCP), is to develop altemative treatment technologies for mixed low-level waste (wastes containing both hazardous and radioactive components) to use in bringing the Rocky Flats Plant (RFP) into compliance with Federal and state regulations and agreements. Approximately 48,000 cubic feet of untreated low-level mixed waste, for which treatment has not been specified, are stored at the RFP. The cleanup of the Rocky Flats site is driven by agreements between DOE, the Environmental Protection Agency (EPA), and the Colorado Department of Health (CDH). Under these agreements, a Comprehensive Treatment and Management Plan (CTMP) was drafted to outline the mechanisms by which RFP will achieve compliance with the regulations and agreements. This document describes DOE`s strategy to treat low-level mixed waste to meet Land Disposal Restrictions and sets specific milestones related to the regulatory aspects of technology development. These milestones detail schedules for the development of technologies to treat all of the mixed wastes at the RFP. Under the Federal Facilities Compliance Act (FFCA), the CTMP has been incorporated into Rocky Flats Plant Conceptual Site Treatment Plan (CSTP). The CSTP will become the Rocky Flats Plant site Treatment Plan in 1995 and will supersede the CTMP.

  11. Star Wreck

    E-Print Network [OSTI]

    Alexander Kusenko; Mikhail Shaposhnikov; P. G. Tinyakov; Igor I. Tkachev

    1998-02-03T23:59:59.000Z

    Electroweak models with low-energy supersymmetry breaking predict the existence of stable non-topological solitons, Q-balls, that can be produced in the early universe. The relic Q-balls can accumulate inside a neutron star and gradually absorb the baryons into the scalar condensate. This causes a slow reduction in the mass of the star. When the mass reaches a critical value, the neutron star becomes unstable and explodes. The cataclysmic destruction of the distant neutron stars may be the origin of the gamma-ray bursts.

  12. Chemical tracking at the Rocky Flats Plant

    SciTech Connect (OSTI)

    Costain, D.B.

    1994-04-01T23:59:59.000Z

    EG&G Rocky Flats, Inc., has developed a chemical tracking system to support compliance with the Emergency Planning and community Right-to-Know Act (EPCRA) at the Rocky Flats Plant. This system, referred to as the EPCRA Chemical Control system (ECCS), uses bar code technology to uniquely identify and track the receipt, distribution, and use of chemicals. Chemical inventories are conducted using hand-held electronic scanners to update a site wide chemical database on a VAX 6000 computer. Information from the ECCS supports preparation of the EPCRA Tier II and Form R reports on chemical storage and use.

  13. PCB fluxes from the sediment to the water column following resuspension A column experiment

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    PCB fluxes from the sediment to the water column following resuspension ­ A column experiment, have been specially designed to study PCB behavior during sediment resuspension, settling resuspension and settling. The sediment should then get more reduced due to the progressive bacterial

  14. The Chemical Evolution of the Universe I High Column Density Absorbers

    E-Print Network [OSTI]

    Mathlin, G P; Churches, D K; Edmunds, M G

    2000-01-01T23:59:59.000Z

    We construct a simple, robust model of the chemical evolution of galaxies from high to low redshift, and apply it to published observations of damped Lyman-alpha quasar absorption line systems (DLAs). The elementary model assumes quiescent star formation and isolated galaxies (no interactions, mergers or gas flows). We consider the influence of dust and chemical gradients in the galaxies, and hence explore the selection effects in quasar surveys. We fit individual DLA systems to predict some observable properties of the absorbing galaxies, and also indicate the expected redshift behaviour of chemical element ratios involving nucleosynthetic time delays. Despite its simplicity, our `monolithic collapse' model gives a good account of the distribution and evolution of the metallicity and column density of DLAs, and of the evolution of the global star formation rate and gas density below redshifts z 3. However, from the comparison of DLA observations with our model, it is clear that star formation rates at higher...

  15. Neal Lane: Science in a Flat World

    SciTech Connect (OSTI)

    Neal Lane

    2006-09-12T23:59:59.000Z

    Lane discusses the changes that have taken place in the world since World War II that have made it "flatter," referring to Thomas L. Friedman's book, The World is Flat. Friedman's main premise is that inexpensive telecommunications is bringing about unhampered international competition, the demise of economic stability, and a trend toward outsourcing services, such as computer programming, engineering and science research.

  16. Neal Lane: Science in a Flat World

    ScienceCinema (OSTI)

    Neal Lane

    2010-09-01T23:59:59.000Z

    Lane discusses the changes that have taken place in the world since World War II that have made it "flatter," referring to Thomas L. Friedman's book, The World is Flat. Friedman's main premise is that inexpensive telecommunications is bringing about unhampered international competition, the demise of economic stability, and a trend toward outsourcing services, such as computer programming, engineering and science research.

  17. Evacuated flat-plate solar collectors

    SciTech Connect (OSTI)

    Whittemore, P.G.

    1981-09-15T23:59:59.000Z

    A structural support system is disclosed for use in an evacuated, flat-plate, solar collector to eliminate the problem of stress fractures in a glass cover plate. Nonlinearly spaced supports are used within the collector to dampen vibrations in the glass cover and to prevent overdeflection before buckling or stress fractures occur.

  18. Flat Space Limit of (Higher-Spin) Cardy Formula

    E-Print Network [OSTI]

    Max Riegler

    2014-11-14T23:59:59.000Z

    In this note I derive the flat space limit of the modified Cardy formula associated with inner horizons and show that it reproduces the correct Galilean conformal field theory counting of flat space cosmology microstates. l also determine the entropy of flat space cosmologies in flat space chiral gravity in this way. In addition, I derive a Cardy-like expression for flat space cosmologies with spin-3 charges and thus give a prediction for the corresponding Galilean conformal field theory counting of flat space cosmology microstates with spin-3 charges.

  19. Thermal Analysis of LANL Ion Exchange Column

    SciTech Connect (OSTI)

    Laurinat, J.E.

    1999-06-16T23:59:59.000Z

    This document reports results from an ion exchange column heat transfer analysis requested by Los Alamos National Laboratory (LANL). The object of the analysis is to demonstrate that the decay heat from the Pu-238 will not cause resin bed temperatures to increase to a level where the resin significantly degrades.

  20. A COLUMN GENERATION APPROACH FOR GRAPH COLORING

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    set in the graph). We use a column generation method for implicit optimization of the linear program based on an integer programming formulation of the graph coloring problem. This formulation, called is an assignment of labels to each vertex such that the endpoints of any edge have different labels. A minimum

  1. The first stars: Where did they form?

    E-Print Network [OSTI]

    Jordi Miralda-Escude

    1999-12-15T23:59:59.000Z

    Several emerging links between high-redshift observational cosmology and the Galactic fossil evidence found in the kinematics, metallicities and ages of Milky Way stars are discussed. In a flat Cold Dark Matter model with $\\Omega\\simeq 0.3$ that agrees with present large-scale structure observations, the oldest stars in the Milky Way should have formed in the first halos where gas was able to cool, at $z\\simeq 20$. These earliest, weakly bound dwarf galaxies probably turned only a small fraction of their gas to stars, which should be metal-poor. However, the merging rate in the early universe was much faster than the present one, so massive halos with more efficient star formation and metallicities up to the highest values present today in the bulge could have formed less than $10^9$ years after the oldest stars. The mean metallicity produced in the universe by a given redshift is related to the mean surface brightness of star-forming galaxies above this redshift, and also to the reionization epoch if galaxies were the dominant sources of ionizing radiation. The biased distribution of the early dwarf galaxies where the first stars formed should result in an age gradient with radius of the low-metallicity stars in the Milky Way, with the oldest ones concentrated in the bulge and the youngest in the outer halo.

  2. Radiation content of Conformally flat initial data

    E-Print Network [OSTI]

    C. O. Lousto; R. H. Price

    2004-01-11T23:59:59.000Z

    We study the radiation of energy and linear momentum emitted to infinity by the headon collision of binary black holes, starting from rest at a finite initial separation, in the extreme mass ratio limit. For these configurations we identify the radiation produced by the initially conformally flat choice of the three geometry. This identification suggests that the radiated energy and momentum of headon collisions will not be dominated by the details of the initial data for evolution of holes from initial proper separations $L_0\\geq7M$. For non-headon orbits, where the amount of radiation is orders of magnitude larger, the conformally flat initial data may provide a relative even better approximation.

  3. Basic TRUEX process for Rocky Flats Plant

    SciTech Connect (OSTI)

    Leonard, R.A.; Chamberlain, D.B.; Dow, J.A.; Farley, S.E.; Nunez, L.; Regalbuto, M.C.; Vandegrift, G.F.

    1994-08-01T23:59:59.000Z

    The Generic TRUEX Model was used to develop a TRUEX process flowsheet for recovering the transuranics (Pu, Am) from a nitrate waste stream at Rocky Flats Plant. The process was designed so that it is relatively insensitive to changes in process feed concentrations and flow rates. Related issues are considered, including solvent losses, feed analysis requirements, safety, and interaction with an evaporator system for nitric acid recycle.

  4. Geothermal: Sponsored by OSTI -- Telephone Flat Geothermal Development...

    Office of Scientific and Technical Information (OSTI)

    Telephone Flat Geothermal Development Project Environmental Impact Statement Environmental Impact Report. Final: Comments and Responses to Comments Geothermal Technologies Legacy...

  5. Remote geologic structural analysis of Yucca Flat

    SciTech Connect (OSTI)

    Foley, M.G.; Heasler, P.G.; Hoover, K.A. (Pacific Northwest Lab., Richland, WA (United States)); Rynes, N.J. (Northern Illinois Univ., De Kalb, IL (United States)); Thiessen, R.L.; Alfaro, J.L. (Washington State Univ., Pullman, WA (United States))

    1991-12-01T23:59:59.000Z

    The Remote Geologic Analysis (RGA) system was developed by Pacific Northwest Laboratory (PNL) to identify crustal structures that may affect seismic wave propagation from nuclear tests. Using automated methods, the RGA system identifies all valleys in a digital elevation model (DEM), fits three-dimensional vectors to valley bottoms, and catalogs all potential fracture or fault planes defined by coplanar pairs of valley vectors. The system generates a cluster hierarchy of planar features having greater-than-random density that may represent areas of anomalous topography manifesting structural control of erosional drainage development. Because RGA uses computer methods to identify zones of hypothesized control of topography, ground truth using a well-characterized test site was critical in our evaluation of RGA's characterization of inaccessible test sites for seismic verification studies. Therefore, we applied RGA to a study area centered on Yucca Flat at the Nevada Test Site (NTS) and compared our results with both mapped geology and geologic structures and with seismic yield-magnitude models. This is the final report of PNL's RGA development project for peer review within the US Department of Energy Office of Arms Control (OAC) seismic-verification community. In this report, we discuss the Yucca Flat study area, the analytical basis of the RGA system and its application to Yucca Flat, the results of the analysis, and the relation of the analytical results to known topography, geology, and geologic structures. 41 refs., 39 figs., 2 tabs.

  6. Remote geologic structural analysis of Yucca Flat

    SciTech Connect (OSTI)

    Foley, M.G.; Heasler, P.G.; Hoover, K.A. [Pacific Northwest Lab., Richland, WA (United States); Rynes, N.J. [Northern Illinois Univ., De Kalb, IL (United States); Thiessen, R.L.; Alfaro, J.L. [Washington State Univ., Pullman, WA (United States)

    1991-12-01T23:59:59.000Z

    The Remote Geologic Analysis (RGA) system was developed by Pacific Northwest Laboratory (PNL) to identify crustal structures that may affect seismic wave propagation from nuclear tests. Using automated methods, the RGA system identifies all valleys in a digital elevation model (DEM), fits three-dimensional vectors to valley bottoms, and catalogs all potential fracture or fault planes defined by coplanar pairs of valley vectors. The system generates a cluster hierarchy of planar features having greater-than-random density that may represent areas of anomalous topography manifesting structural control of erosional drainage development. Because RGA uses computer methods to identify zones of hypothesized control of topography, ground truth using a well-characterized test site was critical in our evaluation of RGA`s characterization of inaccessible test sites for seismic verification studies. Therefore, we applied RGA to a study area centered on Yucca Flat at the Nevada Test Site (NTS) and compared our results with both mapped geology and geologic structures and with seismic yield-magnitude models. This is the final report of PNL`s RGA development project for peer review within the US Department of Energy Office of Arms Control (OAC) seismic-verification community. In this report, we discuss the Yucca Flat study area, the analytical basis of the RGA system and its application to Yucca Flat, the results of the analysis, and the relation of the analytical results to known topography, geology, and geologic structures. 41 refs., 39 figs., 2 tabs.

  7. Control of an industrial polymerization reactor using flatness *, P. Rouchona

    E-Print Network [OSTI]

    Control of an industrial polymerization reactor using flatness N. Petita, *, P. Rouchona , J polypropylene reactor. This is the first industrial process-controller to use the so-called flatness property tank reactor; Control; Flatness; Industrial application 1. Introduction The aim of this paper

  8. NATURAL HERITAGE RESOURCES OF THE ROCKY FLATS ENVIRONMENTAL TECHNOLOGY SITE

    E-Print Network [OSTI]

    NATURAL HERITAGE RESOURCES OF THE ROCKY FLATS ENVIRONMENTAL TECHNOLOGY SITE AND THEIR CONSERVATION Methods 3 Rocky Flats Conservation Site Description 10 Walnut Creek Conservation Site Description 22 Rocky Flats Conservation Site 16 Table 3: Known Natural Elements in the Walnut Creek Conservation Site 23

  9. RHIC | STAR Detector

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

    about the collision. STAR TPC The Heart of STAR STAR's "heart" is the Time Projection Chamber which tracks and identifies particles emerging from heavy ion collisions. As each...

  10. Query execution in column-oriented database systems

    E-Print Network [OSTI]

    Abadi, Daniel J

    2008-01-01T23:59:59.000Z

    There are two obvious ways to map a two-dimension relational database table onto a one-dimensional storage interface: store the table row-by-row, or store the table column-by-column. Historically, database system implementations ...

  11. Introduction Flattening the Earth Continuation procedure Flat Earth Numerical simulations Continuation from a flat to a round Earth model

    E-Print Network [OSTI]

    Boyer, Edmond

    Introduction Flattening the Earth Continuation procedure Flat Earth Numerical simulations Continuation from a flat to a round Earth model in the coplanar orbit transfer problem M. Cerf1, T. Haberkorn, SADCO 2011, March 2nd M. Cerf, T. Haberkorn, E. Tr´elat Continuation from a flat to a round Earth model

  12. Cross flow cyclonic flotation column for coal and minerals beneficiation

    DOE Patents [OSTI]

    Lai, Ralph W. (Upper St. Clair, PA); Patton, Robert A. (Pittsburgh, PA)

    2000-01-01T23:59:59.000Z

    An apparatus and process for the separation of coal from pyritic impurities using a modified froth flotation system. The froth flotation column incorporates a helical track about the inner wall of the column in a region intermediate between the top and base of the column. A standard impeller located about the central axis of the column is used to generate a centrifugal force thereby increasing the separation efficiency of coal from the pyritic particles and hydrophillic tailings.

  13. Quantitative analysis of SCIAMACHY carbon monoxide total column measurements

    E-Print Network [OSTI]

    Laat, Jos de

    , SCIAMACHY CO total column retrievals are of sufficient quality to provide useful new information]. Ground-based FTIR measurements provide high quality total column measurements but have very limitedQuantitative analysis of SCIAMACHY carbon monoxide total column measurements A. T. J. de Laat,1,2 A

  14. Preparation and Characterization of Monolithic Porous Capillary Columns Loaded with

    E-Print Network [OSTI]

    Zare, Richard N.

    of the octadecylsilica (ODS) stationary phase occur in a single step. The presence of the particles in the column greatly the particles and the sol-gel matrix. The perfor- mance of these sol-gel/ODS capillary columns was evalu- ated in columns with immobilized 3-µm ODS par- ticles. The efficiency and resolution are enhanced when 3-µm ODS

  15. Active constraint regions for optimal operation of distillation columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Active constraint regions for optimal operation of distillation columns Magnus G. Jacobsen the control structure of distillation columns, with optimal operation in mind, it is important to know how for distillation columns change with variations in energy cost and feed flow rate. The production of the most

  16. Model Predictive Control of a Kaibel Distillation Column

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Model Predictive Control of a Kaibel Distillation Column Martin Kvernland Ivar Halvorsen Sigurd (e-mail: skoge@ntnu.no) Abstract: This is a simulation study on controlling a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared

  17. Economically Optimal Control of Kaibel Distillation Column: Fixed boilup rate

    E-Print Network [OSTI]

    Skogestad, Sigurd

    : In this study, a control structure is designed for a 4-product dividing wall (Kaibel) distillation column, basedEconomically Optimal Control of Kaibel Distillation Column: Fixed boilup rate Maryam Ghadrdan distillation column; Vapour split manipulation; Self-optimizing control. 1. INTRODUCTION Thermally coupled

  18. Optimal Synthesis of Complex Distillation ColumnsUsing Rigorous Models

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    a review of recent work for the optimal design of distillation of individual columns using tray review of the area of optimal design and synthesis of distillation columns, emphasizing recentOptimal Synthesis of Complex Distillation ColumnsUsing Rigorous Models Ignacio E. Grossmann1 , Pío

  19. Geometrical Wake of a Smooth Flat Collimator

    SciTech Connect (OSTI)

    Stupakov, G.V.; /SLAC

    2011-09-09T23:59:59.000Z

    A transverse geometrical wake generated by a beam passing through a smooth flat collimator with a gradually varying gap between the upper and lower walls is considered. Based on generalization of the approach recently developed for a smooth circular taper we reduce the electromagnetic problem of the impedance calculation to the solution of two much simpler static problems - a magnetostatic and an electrostatic ones. The solution shows that in the limit of not very large frequencies, the impedance increases with the ratio h/d where h is the width and d is the distance between the collimating jaws. Numerical results are presented for the NLC Post Linac collimator.

  20. DHS Flat Stanley Project | Department of Energy

    Office of Environmental Management (EM)

    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 for4,645 3,625 1,006 492 742 33 1112011AT&T,Office of Policy, OAPM | DepartmentI Office of ENERGY Science SLAC SiteDHS Flat

  1. Flat Ridge 2 | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489 NoEuropeStrat.pdfInactive JumpFirst Wind (Formerly(RedirectedFlat

  2. Rocky Flats resumes shipments to WIPP

    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 PossibleRadiation Protection TechnicalResonantNovember 15 toAdvancesRock Physics ofRocky Flats

  3. Testing and analysis of structural steel columns subjected to blast loads

    E-Print Network [OSTI]

    Stewart, Lauren K.

    2010-01-01T23:59:59.000Z

    Blast Simulator Testing of Steel Columns and Components. ”Testing of Structural Steel Columns. ” 8 th Internationaland Analysis of Structural Steel Columns Subjected to Blast

  4. Star Power

    ScienceCinema (OSTI)

    None

    2014-11-18T23:59:59.000Z

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  5. Star Power

    SciTech Connect (OSTI)

    None

    2014-10-17T23:59:59.000Z

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  6. Characteristic structure of star-forming clouds

    E-Print Network [OSTI]

    Myers, Philip C

    2015-01-01T23:59:59.000Z

    This paper gives a new way to diagnose the star-forming potential of a molecular cloud region from the probability density function of its column density (N-pdf). It gives expressions for the column density and mass profiles of a symmetric filament having the same N-pdf as a filamentary region. The central concentration of this characteristic filament can distinguish regions and can quantify their fertility for star formation. Profiles are calculated for N-pdfs which are pure lognormal, pure power law, or a combination. In relation to models of singular polytropic cylinders, characteristic filaments can be unbound, bound, or collapsing depending on their central concentration. Such filamentary models of the dynamical state of N-pdf gas are more relevant to star-forming regions than are models of spherical collapse. The star formation fertility of a bound or collapsing filament is quantified by its mean mass accretion rate when in radial free fall. For a given mass per length, the fertility increases with the ...

  7. Risk, media, and stigma at Rocky Flats

    SciTech Connect (OSTI)

    Flynn, J.; Peters, E.; Mertz, C.K.; Slovic, P. [Decision Research, Eugene, OR (United States)] [Decision Research, Eugene, OR (United States)

    1998-12-01T23:59:59.000Z

    Public responses to nuclear technologies are often strongly negative. Events, such as accidents or evidence of unsafe conditions at nuclear facilities, receive extensive and dramatic coverage by the news media. These news stories affect public perceptions of nuclear risks and the geographic areas near nuclear facilities. One result of these perceptions, avoidance behavior, is a form of technological stigma that leads to losses in property values near nuclear facilities. The social amplification of risk is a conceptual framework that attempts to explain how stigma is created through media transmission of information about hazardous places and public perceptions and decisions. This paper examines stigma associated with the US Department of energy`s Rocky Flats facility, a major production plant in the nation`s nuclear weapons complex, located near Denver, Colorado. This study, based upon newspaper analyses and a survey of Denver area residents, finds that the social amplification theory provides a reasonable framework for understanding the events and public responses that took place in regard to Rocky Flats during a 6-year period, beginning with an FBI raid of the facility in 1989.

  8. Synthesis of focusing-and-deflection columns

    SciTech Connect (OSTI)

    Szilagyi, M.; Mui, P.H. [Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)] [Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)

    1995-03-01T23:59:59.000Z

    Szilagyi and Szep have demonstrated that focusing lenses of high performances can be constructed from a column of circular plate electrodes. Later, Szilagyi modified that system to include dipole, quadrupole, and octupole components by partitioning each plate into eight equal sectors. It has already been shown that the additional quadrupole components can indeed bring about substantial improvements in the focusing of charged particle beams. In this article, that design procedure is expanded to construct columns capable of both focusing and deflecting particle beams by just introducing additional dipole components. In this new design, the geometry of the system remains unchanged. The only extra complication is the demand for more individual controls of the sector voltages. Two sample designs, one for negative ions and one for electrons, are presented showing that in both cases a {plus_minus}2.3 mrad diverging beam can be focused down to a spot of less than 50 nm in radius over a scanning circular area of radius 0.25 mm. The details of the two systems are given in Sec. IV along with the source conditions. The performance of the negative ion system is found to be comparable to the published data. For the relativistic electron system, the interaction of individual components to reduce various aberrations is investigated. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

  9. Improved focusing-and-deflection columns

    SciTech Connect (OSTI)

    Mui, P.H.; Szilagyi, M. [Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)] [Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)

    1995-07-01T23:59:59.000Z

    Our earlier design procedures for constructing quadrupole columns are further expanded to include octupole corrector units and ``octupole`` deflectors with no third-order harmonics. The additional complications are finer partitioning of the plates and increased number of voltage controllers. Two sample designs, one having only the additional octupole deflectors and one having both the deflectors and the correctors, are presented and compared to our previous quadrupole system. The additional octupole components are shown to be capable of increasing the current density from 30% to more than 300% for a four-plate system, designed to focus and scan the electron beam over a circular area of 0.25 mm radius. The electron beam is assumed to have an initial divergence of {plus_minus}2.3 mrad, an initial energy of 6 kV, a total energy spread of 1 eV, and a final acceleration of 30 keV. These systems are then slightly reoptimized for a superficial comparison with the commercially available column by Micrion Corporation. The numerical results indicate a potential for substantial improvements, demonstrating the power of this design procedure. Finally, a discussion is presented on how the individual components can interact with each other to reduce the various aberrations. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

  10. Adsorption of branched and dendritic polymers onto flat surfaces: A Monte Carlo study

    SciTech Connect (OSTI)

    Sommer, J.-U. [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany) [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany); Institute for Theoretical Physics, Technische Universität Dresden, 01069 Dresden (Germany); K?os, J. S. [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany) [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany); Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Pozna? (Poland); Mironova, O. N. [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany)] [Leibniz Institute of Polymer Research Dresden e. V., 01069 Dresden (Germany)

    2013-12-28T23:59:59.000Z

    Using Monte Carlo simulations based on the bond fluctuation model we study the adsorption of starburst dendrimers with flexible spacers onto a flat surface. The calculations are performed for various generation number G and spacer length S in a wide range of the reduced temperature ? as the measure of the interaction strength between the monomers and the surface. Our simulations indicate a two-step adsorption scenario. Below the critical point of adsorption, ?{sub c}, a weakly adsorbed state of the dendrimer is found. Here, the dendrimer retains its shape but sticks to the surface by adsorbed spacers. By lowering the temperature below a spacer-length dependent value, ?*(S) < ?{sub c}, a step-like transition into a strongly adsorbed state takes place. In the flatly adsorbed state the shape of the dendrimer is well described by a mean field model of a dendrimer in two dimensions. We also performed simulations of star-polymers which display a simple crossover-behavior in full analogy to linear chains. By analyzing the order parameter of the adsorption transition, we determine the critical point of adsorption of the dendrimers which is located close to the critical point of adsorption for star-polymers. While the order parameter for the adsorbed spacers displays a critical crossover scaling, the overall order parameter, which combines both critical and discontinuous transition effects, does not display simple scaling. The step-like transition from the weak into the strong adsorbed regime is confirmed by analyzing the shape-anisotropy of the dendrimers. We present a mean-field model based on the concept of spacer adsorption which predicts a discontinuous transition of dendrimers due to an excluded volume barrier. The latter results from an increased density of the dendrimer in the flatly adsorbed state which has to be overcome before this state is thermodynamically stable.

  11. Heat Transfer Analysis for a Fixed CST Column

    SciTech Connect (OSTI)

    Lee, S.Y.

    2004-02-19T23:59:59.000Z

    In support of a small column ion exchange (SCIX) process for the Savannah River Site waste processing program, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the crystalline silicotitanate (CST) column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. A series of the modeling calculations has been performed using a computational heat transfer approach. Results for the baseline model indicate that transit times to reach 130 degrees Celsius maximum temperature of the CST-salt solution column are about 96 hours when the 20-in CST column with 300 Ci/liter heat generation source and 25 degrees Celsius initial column temperature is cooled by natural convection of external air as a primary heat transfer mechanism. The modeling results for the 28-in column equipped with water jacket systems on the external wall surface of the column and water coolant pipe at the center of the CST column demonstrate that the column loaded with 300 Ci/liter heat source can be maintained non-boiling indefinitely. Sensitivity calculations for several alternate column sizes, heat loads of the packed column, engineered cooling systems, and various ambient conditions at the exterior wall of the column have been performed under the reference conditions of the CST-salt solution to assess the impact of those parameters on the peak temperatures of the packed column for a given transient time. The results indicate that a water-coolant pipe at the center of the CST column filled with salt solution is the most effective one among the potential design parameters related to the thermal energy dissipation of decay heat load. It is noted that the cooling mechanism at the wall boundary of the column has significant impact on maximum and wall temperatures of the column. In addition, the results computed by the present model were verified by the theoretical results. The analysis results will provide quantitative information associated with the process heat control and management of the CST base design. For example, transient responses of the CST system under a loss-of-flow accident condition will provide safety design information for an emergency cooling system of the column.

  12. Energy Star

    E-Print Network [OSTI]

    Reihl, K.; Tullos, A.

    2012-01-01T23:59:59.000Z

    is a joint program of: ? U.S. Environmental Protection Agency (EPA) ? U.S. Department of Energy (DOE) ? Mission: ? ?Help us all save money and protect the environment through energy efficient products and practices.? ? History: ? 1992 ? Energy... Star Label introduced for energy-efficient products ? Expanded to include technical information & tools ? Website: www.energystar.gov ESL-KT-12-10-08 CATEE 2012: Clean Air Through Energy Efficiency Conference, Galveston, TX, October 9-11, 2012...

  13. flats for rent 2 | 3 How to find private

    E-Print Network [OSTI]

    Painter, Kevin

    .lettingweb.com/student-flats-heriot-watt-university www.citylets.co.uk www.landlordaccreditationscotland.com www.espc.com www.rightmove.co.uk www

  14. EIS-0276: Rocky Flats Plutonium Storage, Golden, Colorado

    Broader source: Energy.gov [DOE]

    This EIS analyzes DOE's proposed action to provide safe interim storage of approximately 10 metric tons of plutonium at the Rocky Flats Environmental Technology Site (RFETS).

  15. 2006 Annual Ecology Report for the Rocky Flats Site

    Office of Legacy Management (LM)

    Ecology Report for the Rocky Flats Site Click on the links below to access different portions of the electronic annual report. 2006 Annual Report Sections Diffuse Knapweed...

  16. adsorption chromatography columns: Topics by E-print Network

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

    conformation and to the results for polymers at flat and energetically homogeneous surfaces. The disorder-induced enhancement of adsorption is confirmed and is shown to be...

  17. Evaluation of Packed Columns in Supercritical Extraction Processes

    E-Print Network [OSTI]

    Rathkamp, P. J.; Fair, J. R.; Humphrey, J. L.

    process. A 10 wt.% aqueous solution of etha nol was extracted in a spray column using super critical carbon dioxide. Mass transfer coefficients were determined to be more than ten times greater than those associated with conventional liquid extraction... form near the bottom when flooding occurs. The column was operated with countercurrent flow, with the more dense aqueous feed entering near the top of the column, and the less dense super critical carbon dioxide entering near the bottom. The light...

  18. accretion column structure: Topics by E-print Network

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

    of Alternative Control Structures for an Ideal Two-Product Reactive Distillation Column Engineering Websites Summary: Comparison of Alternative Control Structures for an...

  19. argon plasma column: Topics by E-print Network

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

    25 Next Page Last Page Topic Index 1 First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon CERN Preprints Summary: We report on the...

  20. Applicability of hydroxylamine nitrate reductant in pulse-column contactors

    SciTech Connect (OSTI)

    Reif, D.J.

    1983-05-01T23:59:59.000Z

    Uranium and plutonium separations were made from simulated breeder reactor spent fuel dissolver solution with laboratory-sized pulse column contactors. Hydroxylamine nitrate (HAN) was used for reduction of plutonium (1V). An integrated extraction-partition system, simulating a breeder fuel reprocessing flowsheet, carried out a partial partition of uranium and plutonium in the second contactor. Tests have shown that acceptable coprocessing can be ontained using HAN as a plutonium reductant. Pulse column performance was stable even though gaseous HAN oxidation products were present in the column. Gas evolution rates up to 0.27 cfm/ft/sup 2/ of column cross section were tested and found acceptable.

  1. INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO.

    E-Print Network [OSTI]

    Birmingham, University of

    INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO. Staff on the Vale Village try to ensure and cleaned to a high standard. Please make sure that you complete this inventory and note down anything which seat x 1 Toilet roll holder x 1 INVENTORY FOR SHACKLETON FLAT NO: BLOCK NO: ROOM NO: NAME: TELEPHONE

  2. INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO.

    E-Print Network [OSTI]

    Birmingham, University of

    INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO. Staff on the Vale Village try to ensure and cleaned to a high standard. Please make sure that you complete this inventory and note down anything which Toilet seat x 1 Toilet roll holder x 1 INVENTORY FOR MASON FLAT NO: BLOCK NO: ROOM NO: NAME: TELEPHONE

  3. INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO.

    E-Print Network [OSTI]

    Birmingham, University of

    INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO. Staff on the Vale Village try to ensure and cleaned to a high standard. Please make sure that you complete this inventory and note down anything which holder x 1 INVENTORY FOR TENNIS COURT BLOCK NO: FLAT NO: ROOM NO: NAME: TELEPHONE EXT. NO: #12;How

  4. INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO.

    E-Print Network [OSTI]

    Birmingham, University of

    INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO. Staff on the Vale Village try to ensure and cleaned to a high standard. Please make sure that you complete this inventory and note down anything which Toilet seat x 1 Toilet roll holder x 1 INVENTORY FOR ELGAR COURT FLAT NO: BLOCK NO: ROOM NO: NAME

  5. INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO.

    E-Print Network [OSTI]

    Birmingham, University of

    INVENTORY FOR ELGAR COURT FLAT NO. BLOCK NO. ROOM NO. Staff on the Vale Village try to ensure and cleaned to a high standard. Please make sure that you complete this inventory and note down anything which rail x 1 INVENTORY FOR MAPLE BANK FLAT NO: BLOCK NO: ROOM NO: NAME: TELEPHONE EXT. NO: #12;How

  6. Commercial Decommissioning at DOE's Rocky Flats

    SciTech Connect (OSTI)

    Freiboth, C.; Sandlin, N.; Schubert, A.; Hansen, S.

    2002-02-25T23:59:59.000Z

    Due in large part to the number of nuclear facilities that make up the DOE complex, DOE-EM work has historically been paperwork intensive and driven by extensive regulations. Requirements for non-nuclear facilities are often grouped with those of nuclear facilities, driving up costs. Kaiser-Hill was interested in applying a commercial model to demolition of these facilities and wanted to apply necessary and sufficient standards to the work activities, but avoid applying unnecessary requirements. Faced with demolishing hundreds of uncontaminated or non-radiologically contaminated facilities, Kaiser-Hill has developed a subcontracting strategy to drastically reduce the cost of demolishing these facilities at Rocky Flats. Aiming to tailor the demolition approach of such facilities to more closely follow commercial practices, Kaiser-Hill recently released a Request for Proposals (RFP) for the demolition of the site's former central administration facility. The RFP significantly reduced requirements for compliance with specific DOE directives. Instead, the RFP required subcontractors to comply with health and safety requirements commonly found in the demolition of similar facilities in a commercial setting. This resulted in a number of bids from companies who have normally not bid on DOE work previously and at a reduced cost over previous approaches. This paper will discuss the details of this subcontracting strategy.

  7. The Critical Mass Laboratory at Rocky Flats

    SciTech Connect (OSTI)

    Rothe, Robert E

    2003-10-15T23:59:59.000Z

    The Critical Mass Laboratory (CML) at Rocky Flats northwest of Denver, Colorado, was built in 1964 and commissioned to conduct nuclear experiments on January 28, 1965. It was built to attain more accurate and precise experimental data to ensure nuclear criticality safety at the plant than were previously possible. Prior to its construction, safety data were obtained from long extrapolations of subcritical data (called in situ experiments), calculated parameters from reactor engineering 'models', and a few other imprecise methods. About 1700 critical and critical-approach experiments involving several chemical forms of enriched uranium and plutonium were performed between then and 1988. These experiments included single units and arrays of fissile materials, reflected and 'bare' systems, and configurations with various degrees of moderation, as well as some containing strong neutron absorbers. In 1989, a raid by the Federal Bureau of Investigation (FBI) caused the plant as a whole to focus on 'resumption' instead of further criticality safety experiments. Though either not recognized or not admitted for a few years, that FBI raid did sound the death knell for the CML. The plant's optimistic goal of resumption evolved to one of deactivation, decommissioning, and plantwide demolition during the 1990s. The once-proud CML facility was finally demolished in April of 2002.

  8. Spectral Modeling Hot Star Winds

    E-Print Network [OSTI]

    Cohen, David

    supernovaeProduce supernovae (neutron stars, black holes)(neutron stars, black holes) ·· Found near birth

  9. Behavior of the Mass Transfer Zone in a Biosorption Column

    E-Print Network [OSTI]

    Volesky, Bohumil

    in a flow-through fixed-bed sorption column enabled the prediction of breakthrough curves for Cu2+ and Ca in a flow-through fixed-bed column. Copper has been chosen as a typical toxic heavy metal with simple

  10. DYNAMICS AND CONTROL OF DISTILLATION COLUMNS A CRITICAL SURVEY

    E-Print Network [OSTI]

    Skogestad, Sigurd

    DYNAMICS AND CONTROL OF DISTILLATION COLUMNS ­ A CRITICAL SURVEY Sigurd Skogestad \\Lambda Chemical, Identification and Control, 18, 177­217, 1997. Abstract Distillation column dynamics and control has been viewed these, the feasibility of using the distillate­bottom structure for control (which was believed

  11. DYNAMICS AND CONTROL OF DISTILLATION COLUMNS -A CRITICAL SURVEY

    E-Print Network [OSTI]

    Skogestad, Sigurd

    DYNAMICS AND CONTROL OF DISTILLATION COLUMNS - A CRITICAL SURVEY Sigurd Skogestad Chemical cation and Control, 18, 177-217, 1997. Abstract Distillation column dynamics and control has been viewed, the feasibility of using the distillate-bottomstructure for control which was believed to be impossible

  12. THE DOS AND DONTS OF DISTILLATION COLUMN CONTROL

    E-Print Network [OSTI]

    Skogestad, Sigurd

    THE DOS AND DON·TS OF DISTILLATION COLUMN CONTROL S. Skogestadà Department of Chemical Engineering distillation column control within the general framework of plant- wide control. In addition, it aims at providing simple recommendations to assist the engineer in designing control systems for distillation

  13. The Adsorption of Arsenic Oxyacids to Iron Oxyhydroxide Columns

    E-Print Network [OSTI]

    The Adsorption of Arsenic Oxyacids to Iron Oxyhydroxide Columns Including Studies of Weakly. (photo: Mr. J. Mähler, image editing Dr. D. Lundberg) #12;The Adsorption of Arsenic Oxyacids to Iron of columns and iron content of the adsorbent material. Experiments have shown that adsorption does occur

  14. 2005 ASHRAE. 109 Groundwater heat pump systems using standing column

    E-Print Network [OSTI]

    ©2005 ASHRAE. 109 ABSTRACT Groundwater heat pump systems using standing column wells the well through the heat pump in an open-loop pipe circuit. Standing column wells have been in use in growing numbers since the advent of geothermal heat pump systems and are recently receiving much more

  15. NONLINEAR MPC BASED ON MULTI-MODEL FOR DISTILLATION COLUMNS

    E-Print Network [OSTI]

    Foss, Bjarne A.

    NONLINEAR MPC BASED ON MULTI-MODEL FOR DISTILLATION COLUMNS Bjarne A. Foss1 , Song-Bo Cong established for a petroleum distillation column through first principle analysis, and its parameters have been-estimation and prediction in a MPC scheme. The controller has been applied to quality control of a FCCU fractionator

  16. THERMAL MODELING OF ION EXCHANGE COLUMNS WITH SPHERICAL RF RESIN

    SciTech Connect (OSTI)

    Lee, S.; King, W.

    2009-12-30T23:59:59.000Z

    Models have been developed to simulate the thermal performance of RF columns fully loaded with radioactive cesium. Temperature distributions and maximum temperatures across the column were calculated during Small Column Ion Exchange (SCIX) process upset conditions with a focus on implementation at Hanford. A two-dimensional computational modeling approach was taken to include conservative, bounding estimates for key parameters such that the results will provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on RF. The current full-scale design for the SCIX system includes a central cooling tube, and one objective of these calculations was to examine its elimination to simplify the design. Results confirmed that a column design without a central cooling tube is feasible for RF, allowing for the possibility of significant design simplifications if it can be assumed that the columns are always filled with liquid. With active cooling through the four outer tubes, the maximum column diameter expected to maintain the temperature below the assumed media and safety limits is 26 inches, which is comparable to the current design diameter. Additional analysis was conducted to predict the maximum column temperatures for the previously unevaluated accident scenario involving inadvertent drainage of liquid from a cesium-saturated column, with retention of the ion exchange media and cesium in the column. As expected, much higher maximum temperatures are observed in this case due to the poor heat transfer properties of air versus liquid. For this hypothetical accident scenario involving inadvertent and complete drainage of liquid from a cesium-saturated column, the modeling results indicate that the maximum temperature within a 28 inch diameter RF column with external cooling is expected to exceed 250 C within 2 days, while the maximum temperature of a 12 inch column is maintained below 100 C. In addition, the calculation results demonstrate that the cooling tube system external to an air-filled column is not highly effective at reducing the maximum temperature, but the baseline design using a central cooling tube inside the column provides sufficient cooling to maintain the maximum temperature near the assumed safety limit.

  17. The Chemical Evolution of the Universe I: High Column Density Absorbers

    E-Print Network [OSTI]

    G. P. Mathlin; A. C. Baker; D. K. Churches; M. G. Edmunds

    2000-09-14T23:59:59.000Z

    We construct a simple, robust model of the chemical evolution of galaxies from high to low redshift, and apply it to published observations of damped Lyman-alpha quasar absorption line systems (DLAs). The elementary model assumes quiescent star formation and isolated galaxies (no interactions, mergers or gas flows). We consider the influence of dust and chemical gradients in the galaxies, and hence explore the selection effects in quasar surveys. We fit individual DLA systems to predict some observable properties of the absorbing galaxies, and also indicate the expected redshift behaviour of chemical element ratios involving nucleosynthetic time delays. Despite its simplicity, our `monolithic collapse' model gives a good account of the distribution and evolution of the metallicity and column density of DLAs, and of the evolution of the global star formation rate and gas density below redshifts z 3. However, from the comparison of DLA observations with our model, it is clear that star formation rates at higher redshifts (z>3) are enhanced. Galaxy interactions and mergers, and gas flows very probably play a major role.

  18. HEAT TRANSFER ANALYSIS FOR ION-EXCHANGE COLUMN SYSTEM

    SciTech Connect (OSTI)

    Lee, S.; King, W.

    2011-05-23T23:59:59.000Z

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed, inadvertent column drainage, and loss of active cooling in the column. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature.

  19. A quantum kinematics for asymptotically flat spacetimes

    E-Print Network [OSTI]

    Miguel Campiglia; Madhavan Varadarajan

    2014-12-17T23:59:59.000Z

    We construct a quantum kinematics for asymptotically flat spacetimes based on the Koslowski-Sahlmann (KS) representation. The KS representation is a generalization of the representation underlying Loop Quantum Gravity (LQG) which supports, in addition to the usual LQG operators, the action of `background exponential operators' which are connection dependent operators labelled by `background' $su(2)$ electric fields. KS states have, in addition to the LQG state label corresponding to 1 dimensional excitations of the triad, a label corresponding to a `background' electric field which describes 3 dimensional excitations of the triad. Asymptotic behaviour in quantum theory is controlled through asymptotic conditions on the background electric fields which label the {\\em states} and the background electric fields which label the {\\em operators}. Asymptotic conditions on the triad are imposed as conditions on the background electric field state label while confining the LQG spin net graph labels to compact sets. We show that KS states can be realised as wave functions on a quantum configuration space of generalized connections and that the asymptotic behaviour of each such generalized connection is determined by that of the background electric fields which label the background exponential operators. Similar to the spatially compact case, the Gauss Law and diffeomorphism constraints are then imposed through Group Averaging techniques to obtain a large sector of gauge invariant states. It is shown that this sector supports a unitary action of the group of asymptotic rotations and translations and that, as anticipated by Friedman and Sorkin, for appropriate spatial topology, this sector contains states which display fermionic behaviour under $2\\pi$ rotations.

  20. Calculation of CO2 column heights in depleted gas fields from known pre-production gas column heights

    E-Print Network [OSTI]

    Calculation of CO2 column heights in depleted gas fields from known pre-production gas column that the CO2 is in a dense phase (either liquid or supercritical). Accurate assessment of the storage capacity also requires an estimation of the amount of CO2 that can be safely stored beneath the reservoir seal

  1. Chern-Simons classes of flat connections on supermanifolds

    E-Print Network [OSTI]

    JN Iyer; Un Iyer

    2007-07-16T23:59:59.000Z

    In this note we define Chern-Simons classes of a superconnection $D+L$ on a complex supervector bundle $E$ such that $D$ is flat and preserves the grading, and $L$ is an odd endomorphism of $E$ on a supermanifold. As an application we obtain a definition of Chern-Simons classes of a (not necessarily flat) morphism between flat vector bundles on a smooth manifold. We extend Reznikov's theorem on triviality of these classes when the manifold is a compact K\\"ahler manifold or a smooth complex quasi--projective variety, in degrees > 1.

  2. Chern-Simons classes of flat connections on supermanifolds

    E-Print Network [OSTI]

    Iyer, JN

    2007-01-01T23:59:59.000Z

    In this note we define Chern-Simons classes of a superconnection $D+L$ on a complex supervector bundle $E$ such that $D$ is flat and preserves the grading, and $L$ is an odd endomorphism of $E$ on a supermanifold. As an application we obtain a definition of Chern-Simons classes of a (not necessarily flat) morphism between flat vector bundles on a smooth manifold. We extend Reznikov's theorem on triviality of these classes when the manifold is a compact K\\"ahler manifold or a smooth complex quasi--projective variety, in degrees > 1.

  3. Column-by-column compositional mapping by Z-contrast imaging

    SciTech Connect (OSTI)

    Molina Rubio, Sergio I [ORNL; Varela del Arco, Maria [ORNL; Sales Lerida, David [ORNL; Galindo, Pedro [Universidad de Cadiz, Spain; Fuster, David [Instituto de Microelectronica de Madrid (CNM, CSIC); Gonzalez, Yolanda [Instituto de Microelectronica de Madrid (CNM, CSIC); Alen, B. [Instituto de Microelectronica de Madrid (CNM, CSIC); Gonzalez, Luisa [Instituto de Microelectronica de Madrid (CNM, CSIC); Pennycook, Stephen J [ORNL

    2009-01-01T23:59:59.000Z

    A phenomenological method is developed to determine the composition of materials, with atomic column resolution, by analysis of integrated intensities of aberration-corrected Z-contrast scanning transmission electron microscopy images. The method is exemplified for InAsxP1-x alloys using epitaxial thin films with calibrated compositions as standards. Using this approach we have determined the composition of the two-dimensional wetting layer formed between self-assembled InAs quantum wires on InP (001) substrates. The method utilizes a series of B coefficients that models the background signal in Z-contrast images, which is unaccounted for by image simulations.

  4. Active vapor split control for dividing-wall columns Journal: Industrial & Engineering Chemistry Research

    E-Print Network [OSTI]

    Skogestad, Sigurd

    @ntnu.no Abstract Dividing-wall distillation columns offer large potential energy savings over conventional column column Introduction Dividing-wall distillation columns such as Petlyuk arrangements and the Kaibel column vapor fraction Purities (mol %): 97.6 % (D), 97.3 % (S); 99.6 % (B) Stages: 40 in prefractionator and 80

  5. Flat plate puncture test convergence study.

    SciTech Connect (OSTI)

    Snow, Spencer (Idaho National Laboratories); Ammerman, Douglas James; Molitoris, David (Westinghouse); Tso, Chi-Fung (ARUP); Yaksh, Mike (NAC International)

    2010-10-01T23:59:59.000Z

    The ASME Task Group on Computational Mechanics for Explicit Dynamics is investigating the types of finite element models needed to accurately solve various problems that occur frequently in cask design. One type of problem is the 1-meter impact onto a puncture spike. The work described in this paper considers this impact for a relatively thin-walled shell, represented as a flat plate. The effects of mesh refinement, friction coefficient, material models, and finite element code will be discussed. The actual punch, as defined in the transport regulations, is 15 cm in diameter with a corner radius of no more than 6 mm. The punch used in the initial part of this study has the same diameter, but has a corner radius of 25 mm. This more rounded punch was used to allow convergence of the solution with a coarser mesh. A future task will be to investigate the effect of having a punch with a smaller corner radius. The 25-cm thick type 304 stainless steel plate that represents the cask wall is 1 meter in diameter and has added mass on the edge to represent the remainder of the cask. The amount of added mass to use was calculated using Nelm's equation, an empirically derived relationship between weight, wall thickness, and ultimate strength that prevents punch through. The outer edge of the plate is restrained so that it can only move in the direction parallel to the axis of the punch. Results that are compared include the deflection at the edge of the plate, the deflection at the center of the plate, the plastic strains at radius r=50 cm and r=100 cm , and qualitatively, the distribution of plastic strains. The strains of interest are those on the surface of the plate, not the integration point strains. Because cask designers are using analyses of this type to determine if shell will puncture, a failure theory, including the effect of the tri-axial nature of the stress state, is also discussed. The results of this study will help to determine what constitutes an adequate finite element model for analyzing the puncture hypothetical accident.

  6. Seismic rehabilitation of a reinforced concrete flat-slab structure 

    E-Print Network [OSTI]

    Jimenez, Laila Margarita

    1999-01-01T23:59:59.000Z

    The effectiveness of seismic rehabilitation techniques used to eliminate punching shear failures was assessed for flat-slab structural systems. This type of retrofit was evaluated for a four-story reinforced concrete (RC) ...

  7. DOE's Former Rocky Flats Weapons Production Site to Become National...

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

    Flats nuclear weapons production site to the Department of the Interior's (DOI) U.S. Fish and Wildlife Service (FWS) for use as a National Wildlife Refuge. After more than a...

  8. atomically flat gold: Topics by E-print Network

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

    Flat(Tire1) Intact(Tire1) StartFinish Inflate(Tire1 Starner, Thad E. 147 Local and global instabilities in nanosize rectangular prismatic gold specimens R.C. Batra *, A.A....

  9. Modified Ricci flow and asymptotically non-flat spaces

    E-Print Network [OSTI]

    Shubhayu Chatterjee; Narayan Banerjee

    2013-04-08T23:59:59.000Z

    The present work extends the application of a modified Ricci flow equation to an asymptotically non flat space, namely Marder's cylindrially symmetric space. It is found that the flow equation has a solution at least in a particular case.

  10. MODELING AND SIMULATION OF SOLID FLUIDIZATION IN A RESIN COLUMN

    SciTech Connect (OSTI)

    Lee, S.

    2014-06-24T23:59:59.000Z

    The objective of the present work is to model the resin particles within the column during fluidization and sedimentation processes using computation fluid dynamics (CFD) approach. The calculated results will help interpret experimental results, and they will assist in providing guidance on specific details of testing design and establishing a basic understanding of particle’s hydraulic characteristics within the column. The model is benchmarked against the literature data and the test data (2003) conducted at Savannah River Site (SRS). The paper presents the benchmarking results and the modeling predictions of the SRS resin column using the improved literature correlations applicable for liquid-solid granular flow.

  11. SENSITIVITY ANALYSIS FOR SALTSTONE DISPOSAL UNIT COLUMN DEGRADATION ANALYSES

    SciTech Connect (OSTI)

    Flach, G.

    2014-10-28T23:59:59.000Z

    PORFLOW related analyses supporting a Sensitivity Analysis for Saltstone Disposal Unit (SDU) column degradation were performed. Previous analyses, Flach and Taylor 2014, used a model in which the SDU columns degraded in a piecewise manner from the top and bottom simultaneously. The current analyses employs a model in which all pieces of the column degrade at the same time. Information was extracted from the analyses which may be useful in determining the distribution of Tc-99 in the various SDUs throughout time and in determining flow balances for the SDUs.

  12. Flat Lens Criterion by Small-Angle Phase

    E-Print Network [OSTI]

    Ott, Peter; Lezec, Henri J; Chau, Kenneth J

    2015-01-01T23:59:59.000Z

    We show that a classical imaging criterion based on angular dependence of small-angle phase can be applied to any system composed of planar, uniform media to determine if it is a flat lens capable of forming a real paraxial image and to estimate the image location. The real paraxial image location obtained by this method shows agreement with past demonstrations of far-field flat-lens imaging and can even predict the location of super-resolved images in the near-field. The generality of this criterion leads to several new predictions: flat lenses for transverse-electric polarization using dielectric layers, a broadband flat lens working across the ultraviolet-visible spectrum, and a flat lens configuration with an image plane located up to several wavelengths from the exit surface. These predictions are supported by full-wave simulations. Our work shows that small-angle phase can be used as a generic metric to categorize and design flat lenses.

  13. A two component jet model for the X-ray afterglow flat segment in short GRB 051221A

    E-Print Network [OSTI]

    Zhi-Ping Jin; Ting Yan; Yi-Zhong Fan; Da-Ming Wei

    2007-01-20T23:59:59.000Z

    In the double neutron star merger or neutron star-black hole merger model for short GRBs, the outflow launched might be mildly magnetized and neutron rich. The magnetized neutron-rich outflow will be accelerated by the magnetic and thermal pressure and may form a two component jet finally, as suggested by Vlahakis, Peng & K\\"{o}nigl (2003). We show in this work that such a two component jet model could well reproduce the multi-wavelength afterglow lightcurves, in particular the X-ray flat segment, of short GRB 051221A. In this model, the central engine need not to be active much longer than the prompt $\\gamma-$ray emission.

  14. Cyclic behavior and design of steel columns subjected to large drift

    E-Print Network [OSTI]

    Newell, James David

    2008-01-01T23:59:59.000Z

    testing. These deep columns have larger web width-to-that provided by the web of a deep column with a similarflange and web local buckling for the deep column sections.

  15. Transformations of mercury in the marine water column

    E-Print Network [OSTI]

    Munson, Kathleen M. (Kathleen May)

    2014-01-01T23:59:59.000Z

    Methylation of mercury (Hg) in the marine water column has been hypothesized to serve as the primary source of the bioaccumulating chemical species monomethylmercury (MMHg) to marine food webs. Despite decades of research ...

  16. Optimization Online - Simultaneous Column-and-Row Generation ...

    E-Print Network [OSTI]

    Ibrahim Muter

    2010-11-14T23:59:59.000Z

    Nov 14, 2010 ... Abstract: In this paper, we develop a simultaneous column-and-row generation algorithm that could be applied to a general class of large-scale ...

  17. Practical Application of Distillation Column Energy Control Systems

    E-Print Network [OSTI]

    Matthews, S. A.

    1980-01-01T23:59:59.000Z

    Closed loop computer control of an ethylene column has been shown to save $350/day in improved ethylene recovery and $150/day in reduced energy consumption. These savings are achieved through material balance optimization and energy balance...

  18. 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.

  19. Practical Application of Distillation Column Energy Control Systems 

    E-Print Network [OSTI]

    Matthews, S. A.

    1980-01-01T23:59:59.000Z

    Closed loop computer control of an ethylene column has been shown to save $350/day in improved ethylene recovery and $150/day in reduced energy consumption. These savings are achieved through material balance optimization and energy balance...

  20. Insitu expanding foam based carbon/epoxy sandwich jackets for column retrofit

    E-Print Network [OSTI]

    Danyeur, Alicia

    2008-01-01T23:59:59.000Z

    the construction and testing of 6 concrete columns and aUp Creating Gap with Concrete Base Column testing continuedagainst the concrete base was witnessed during testing and

  1. Revised Thermal Analysis of LANL Ion Exchange Column

    SciTech Connect (OSTI)

    Laurinat, J

    2006-04-11T23:59:59.000Z

    This document updates a previous calculation of the temperature distributions in a Los Alamos National Laboratory (LANL) ion exchange column.1 LANL operates two laboratory-scale anion exchange columns, in series, to extract Pu-238 from nitric acid solutions. The Defense Nuclear Facilities Safety Board has requested an updated analysis to calculate maximum temperatures for higher resin loading capacities obtained with a new formulation of the Reillex HPQ anion exchange resin. The increased resin loading capacity will not exceed 118 g plutonium per L of resin bed. Calculations were requested for normal operation of the resin bed at the minimum allowable solution feed rate of 30 mL/min and after an interruption of flow at the end of the feed stage, when one of the columns is fully loaded. The object of the analysis is to demonstrate that the decay heat from the Pu-238 will not cause resin bed temperatures to increase to a level where the resin significantly degrades. At low temperatures, resin bed temperatures increase primarily due to decay heat. At {approx}70 C a Low Temperature Exotherm (LTE) resulting from the reaction between 8-12 M HNO{sub 3} and the resin has been observed. The LTE has been attributed to an irreversible oxidation of pendant ethyl benzene groups at the termini of the resin polymer chains by nitric acid. The ethyl benzene groups are converted to benzoic acid moities. The resin can be treated to permanently remove the LTE by heating a resin suspension in 8M HNO{sub 3} for 30-45 minutes. No degradation of the resin performance is observed after the LTE removal treatment. In fact, heating the resin in boiling ({approx}115-120 C) 12 M HNO{sub 3} for 3 hr displays thermal stability analogous to resin that has been treated to remove the LTE. The analysis is based on a previous study of the SRS Frames Waste Recovery (FWR) column, performed in support of the Pu-238 production campaign for NASA's Cassini mission. In that study, temperature transients following an interruption of flow to the column were calculated. The transient calculations were terminated after the maximum resin bed temperature reached the Technical Standard of 60 C, which was set to prevent significant resin degradation. The LANL column differs from the FWR column in that it has a significantly smaller radius, 3.73 cm nominal versus approximately 28 cm. It follows that natural convection removes heat much more effectively from the LANL column, so that the column may reach thermal equilibrium. Consequently, the calculations for a flow interruption were extended until an approach to thermal equilibrium was observed. The LANL ion exchange process also uses a different resin than was used in the FWR column. The LANL column uses Reillex HPQ{trademark} resin, which is more resistant to attack by nitric acid than the Ionac 641{trademark} resin used in the FWR column. Heat generation from the resin oxidation reaction with nitric acid is neglected in this analysis since LANL will be treating the resin to remove the LTE prior to loading the resin in the columns. Calculations were performed using a finite difference computer code, which incorporates models for absorption and elution of plutonium and for forced and natural convection within the resin bed. Calculations for normal column operation during loading were performed using an initial temperature and a feed temperature equal to the ambient air temperature. The model for the normal flow calculations did not include natural convection within the resin bed. The no flow calculations were started with the temperature and concentration profiles at the end of the loading stage, when there would be a maximum amount of plutonium either adsorbed on the resin or in the feed solution in the column.

  2. FROM FLAT DIRECT MODELS TO SEGMENTAL CRF MODELS Geoffrey Zweig and Patrick Nguyen

    E-Print Network [OSTI]

    Hunt, Galen

    the SCRF is better suited. Index Terms-- Flat Direct Model, Segmental CRF, Voice Search, Speech Recognition

  3. From Neutron Stars to Strange Stars

    E-Print Network [OSTI]

    Fridolin Weber

    2001-12-04T23:59:59.000Z

    This paper discusses several most intruigung astrophysical implications connected with the possible absolute stability of strange quark matter.This is followed by a discussion of two astrophysical signals that may point at the existence of quark matter in both isolated neutron stars as well as in neutron stars in low-mass x-ray binaries (LMXBs).

  4. Projective flatness in the quantisation of bosons and fermions

    E-Print Network [OSTI]

    Siye Wu

    2010-10-06T23:59:59.000Z

    We compare the quantisation of linear systems of bosons and fermions. We recall the appearance of projectively flat connection and results on parallel transport in the quantisation of bosons. We then discuss pre-quantisation and quantisation of fermions using the calculus of fermionic variables. We then define a natural connection on the bundle of Hilbert spaces and show that it is projectively flat. This identifies, up to a phase, equivalent spinor representations constructed by various polarisations. We introduce the concept of metaplectic correction for fermions and show that the bundle of corrected Hilbert spaces is naturally flat. We then show that the parallel transport in the bundle of Hilbert spaces along a geodesic is the rescaled projection or the Bogoliubov transformation provided that the geodesic lies within the complement of a cut locus. Finally, we study the bundle of Hilbert spaces when there is a symmetry.

  5. Spectral Formation in X-Ray Pulsar Accretion Columns

    E-Print Network [OSTI]

    Peter A. Becker; Michael T. Wolff

    2005-03-03T23:59:59.000Z

    We present the first self-consistent model for the dynamics and the radiative transfer occurring in bright X-ray pulsar accretion columns, with a special focus on the role of the shock in energizing the emerging X-rays. The pressure inside the accretion column of a luminous X-ray pulsar is dominated by the photons, and consequently the equations describing the coupled radiative-dynamical structure must be solved simultaneously. Spectral formation in these sources is therefore a complex, nonlinear phenomenon. We obtain the analytical solution for the Green's function describing the upscattering of monochromatic radiation injected into the column from the thermal mound located near the base of the flow. The Green's function is convolved with a Planck distribution to model the X-ray spectrum resulting from the reprocessing of blackbody photons produced in the thermal mound. These photons diffuse through the infalling gas and eventually escape out the walls of the column, forming the observed X-ray spectrum. We show that the resulting column-integrated, phase-averaged spectrum has a power-law shape at high energies and a blackbody shape at low energies, in agreement with the observational data for many X-ray pulsars.

  6. Superintegrability in a non-conformally-flat space

    E-Print Network [OSTI]

    E. G. Kalnins; J. M. Kress; W. Miller Jr

    2012-11-07T23:59:59.000Z

    Superintegrable systems in two- and three-dimensional spaces of constant curvature have been extensively studied. From these, superintegrable systems in conformally flat spaces can be constructed by Staeckel transform. In this paper a method developed to establish the superintegrability of the Tremblay-Turbiner-Winternitz system in two dimensions is extended to higher dimensions and a superintegrable system on a non-conformally-flat four-dimensional space is found. In doing so, curvature corrections to the corresponding classical potential are found to be necessary. It is found that some subalgebras of the symmetry algebra close polynomially.

  7. T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial

    E-Print Network [OSTI]

    Skogestad, Sigurd

    T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial heat integrated distillation column Truls Larsson Sigurd Skogestad ÝDepartment of Chemical. Larsson, S. Skogestad Control of a industrial heat integrated distillation column The process QH column

  8. Design of Extraction Column Methanol Recovery System for the TAME Reactive Distillation Process

    E-Print Network [OSTI]

    Al-Arfaj, Muhammad A.

    Design of Extraction Column Methanol Recovery System for the TAME Reactive Distillation Process system for TAME reactive distillation process using extraction column with water as a solvent. The design distillation column which was optimized to recover methanol and recycle water to the extraction column. Other

  9. T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial

    E-Print Network [OSTI]

    Skogestad, Sigurd

    T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial heat integrated distillation column Truls Larsson Sigurd Skogestad y Department of Chemical. Larsson, S. Skogestad Control of a industrial heat integrated distillation column The process Q H column

  10. Control Structure Design for Optimal Operation of 4-Product Thermally Coupled Columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control Structure Design for Optimal Operation of 4-Product Thermally Coupled Columns Deeptanshu: distillation, thermal coupling, Kaibel column, Petlyuk column Prepared for presentation at the James R. Fair distillation arrangements like Kaibel and Petlyuk columns can be challenging. This paper discusses the control

  11. Use of Short-cut Methods to Analyse Optimal Operation of Petlyuk Distillation Columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Use of Short-cut Methods to Analyse Optimal Operation of Petlyuk Distillation Columns Ivar J: Petlyuk distillation column, dividing wall column, optimizing control, minimum energy 1. INTRODUCTION- ments for the level of automatic control and to the design of number of stages in each column section. 2

  12. Use of Shortcut Methods to Analyse Optimal Operation of Petlyuk Distillation Columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Use of Short­cut Methods to Analyse Optimal Operation of Petlyuk Distillation Columns Ivar J: Petlyuk distillation column, dividing wall column, optimizing control, minimum energy 1. INTRODUCTION­ ments for the level of automatic control and to the design of number of stages in each column section. 2

  13. 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.

  14. 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.

  15. 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.

  16. Effects of system densities on distillation column performance

    SciTech Connect (OSTI)

    Fasesan, S.O.; Sanni, S.A.; Taiwo, E.A. [Obafemi Awolowo Univ., Ile-Ife (Nigeria). Dept. of Chemical Engineering

    1998-06-01T23:59:59.000Z

    Distillation experiments were carried out on three binary systems (ethanol-butanol, ethanol-propan-2-ol, and propan-2-ol-butanol) in a 0.1-m internal diameter glass column packed with 8 mm diameter Raschig rings. The experiments were performed under total reflux conditions and at atmospheric pressure. The data collected on column performance showed that performance declined with increasing average bulk liquid density. The results also lend credence to earlier reports on the behavior of column performance with respect to component concentration in the feed mixtures. The system densities of the three binary systems were measured at four different temperatures, 30, 40, 50, and 60 C. The data were compared with the predicted data of Yen-Woods and Multifluid models. The accuracy of the predictions of the Yen-Woods model was rather poor while that of the Multifluid model was very encouraging.

  17. Heat Transfer Calculations for a Fixed CST Bed Column

    SciTech Connect (OSTI)

    Lee, S.Y.

    2001-03-28T23:59:59.000Z

    In support of the crystalline silicotitanate (CST) ion exchange project of High-Level Waste (HLW) Process Engineering, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the CST column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. The modeling and calculations were performed using a computational heat transfer approach.

  18. Extraplanar Dust and Star Formation in Nearby Edge-On Galaxies

    E-Print Network [OSTI]

    J. Christopher Howk; Blair D. Savage

    1998-10-27T23:59:59.000Z

    We present high-resolution ( 0.5 - 2.0. If Milky Way gas-to-dust relationships are appropriate, then these structures have gaseous column densities N_H > 10(21) cm(-2), with very large masses (>10(5) - 10(6) solar masses) and gravitational potential energies (> 10(51) - 10(52) ergs relative to z=0). The estimated column densities suggest molecular gas may be present, and with the estimated masses allows for the possibility of star formation in these dusty clouds. Recent star formation is the likely cause of the discrete H II regions, in some cases associated with relatively blue continuum sources, observed at heights 0.6 < |z| < 0.8 kpc above the disks of these galaxies. The presence of early-type stars at high-z in these galaxies may be related to the extraplanar dust structures seen in our images.

  19. Scaling attractors for quintessence in flat universe with cosmological term

    E-Print Network [OSTI]

    V. V. Kiselev

    2007-02-08T23:59:59.000Z

    For evolution of flat universe, we classify late time and future attractors with scaling behavior of scalar field quintessence in the case of potential, which, at definite values of its parameters and initial data, corresponds to exact scaling in the presence of cosmological constant.

  20. Distributed Roughness Receptivity in a Flat Plate Boundary Layer

    E-Print Network [OSTI]

    Kuester, Matthew Scott

    2014-04-18T23:59:59.000Z

    for the three different unit Reynolds num- ber test conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.4 Spanwise uniformity of boundary layer integral quantities at x = 870 mm for low unit Reynolds number test condition... with the distributed roughness configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.5 Differential pressure across the flat plate leading edge. . . . . . . . . . 25 3.6 Roughness patch (k = 1 mm), before windowing . . . . . . . . . . . . 27 3...

  1. Film cooling on a flat plate: investigating density

    E-Print Network [OSTI]

    Grizzle, Joshua Peter Fletcher

    2009-05-15T23:59:59.000Z

    This study is an investigation of two specific effects on turbine blade film cooling. The effect of coolant to mainstream density ratio and upstream steps was studied. The studies were conducted on two flat plates with 4mm cylindrical film cooling...

  2. Avoidance of a Landau pole by flat contributions in QED

    SciTech Connect (OSTI)

    Klaczynski, Lutz, E-mail: lutz.klaczynski@gmx.de [Department of Physics, Humboldt University Berlin, 12489 Berlin (Germany); Kreimer, Dirk, E-mail: kreimer@mathematik.hu-berlin.de [Alexander von Humboldt Chair in Mathematical Physics, Humboldt University, Berlin 12489 (Germany)

    2014-05-15T23:59:59.000Z

    We consider massless Quantum Electrodynamics in the momentum scheme and carry forward an approach based on Dyson–Schwinger equations to approximate both the ?-function and the renormalized photon self-energy (Yeats, 2011). Starting from the Callan–Symanzik equation, we derive a renormalization group (RG) recursion identity which implies a non-linear ODE for the anomalous dimension and extract a sufficient but not necessary criterion for the existence of a Landau pole. This criterion implies a necessary condition for QED to have no such pole. Solving the differential equation exactly for a toy model case, we integrate the corresponding RG equation for the running coupling and find that even though the ?-function entails a Landau pole it exhibits a flat contribution capable of decreasing its growth, in other cases possibly to the extent that such a pole is avoided altogether. Finally, by applying the recursion identity, we compute the photon propagator and investigate the effect of flat contributions on both spacelike and timelike photons. -- Highlights: •We present an approach to approximate both the ?-function and the photon self-energy. •We find a sufficient criterion for the self-energy to entail the existence of a Landau pole. •We study non-perturbative ‘flat’ contributions that emerge within the context of our approach. •We discuss a toy model and how it is affected by flat contributions.

  3. Flatness of heavy chain systems Nicolas Petit 1

    E-Print Network [OSTI]

    .e. trolleys carrying a fixed length heavy chain that may carry a load, is addressed in the partial derivatives the homogeneous chain carrying a load, see equation (13). In [11] the flatness [3, 4] of heavy chain systems, i dimensional case. Under small angle approximations, these heavy chain systems are described by a 1D partial

  4. Flatness-based control of an irrigation canal using SCADA

    E-Print Network [OSTI]

    -time irrigation operations using a supervision, control, and data acquisition (SCADA) system with automatic centralized controller. Irrigation canals can be viewed and modeled as delay systems since it takes timeFlatness-based control of an irrigation canal using SCADA Tarek Rabbani, Simon Munier, David

  5. Asymptotically flat gravitating spinor field solutions. Step 2 - the compatibility of Dirac equations in a curve and a flat spaces

    E-Print Network [OSTI]

    V. Dzhunushaliev

    2012-01-17T23:59:59.000Z

    Using the fact that a spin connection is defined to an accuracy of a vector it is shown that the spin connection should be modified in such a manner that Dirac equation in a curve space would be compatible with Dirac equation in a flat space.

  6. IT Profession Column --November 2003 Communications of ACM

    E-Print Network [OSTI]

    Guzdial, Mark

    IT Profession Column -- November 2003 Communications of ACM DRAFT 9/12/03 Great Principles and behavior, which I call mechanics, and principles of design. What we call principles are almost always distilled from recurrent patterns observed in practice. Do practices shape to underlying principles? Do

  7. How To Run a Flash Column Contributed by Jeffrey Bode

    E-Print Network [OSTI]

    Yao, Shao Q

    toluene, this will remove the acid without exposing the neat compound to it. 2. Packing the Column a/methanol (100:1 - 100:10); ethyl acetate/acetone (100:0 - 50:50); and toluene with acetone, ethyl acetate. In these cases, the acetic acid can often be safely rotavaped away by adding portions of toluene

  8. Plastic Hinging Behavior of Reinforced Concrete Bridge Columns

    E-Print Network [OSTI]

    Firat Alemdar, Zeynep

    2010-04-27T23:59:59.000Z

    of the seismic performance of four-span large-scale bridge systems at the University of Nevada Reno that details deformations in column hinging regions during response to strong shaking events. In order to evaluate the plastic hinging regions, a photogrammetric...

  9. Water column characterization of anchialine caves in Quintana Roo, Mexico

    E-Print Network [OSTI]

    Dodson, Brett Wayne

    2000-01-01T23:59:59.000Z

    on temperature, salinity, dissolved oxygen, and pH of the caves. Water columns were divided into three zones, brackish, transition, and saline, and a new method was employed to define these boundaries by using "best it" calculations and subsequent regression...

  10. U. L'Aquila INVERTING GOME FORMALDEHYDE COLUMN

    E-Print Network [OSTI]

    Curci, Gabriele

    % of anthropogenic plus biomass burning contribution. Europe is the only continent where anthropogenic VOC emissionsU. L'Aquila CETEMPS INVERTING GOME FORMALDEHYDE COLUMN FOR BIOGENIC EMISSIONS OVER EUROPE Gabriele over Europe is generally overestimated by the state-of-the-art chemistry and transport model GEOS- CHEM

  11. Modeling of Immobilized Cell Columns for Bioconversion and Wastewater Treatment

    E-Print Network [OSTI]

    Gu, Tingyue

    used in bioconversions to produce biological products as well as in wastewater treatmentModeling of Immobilized Cell Columns for Bioconversion and Wastewater Treatment Tingyue Gu* and Mei for wastewater treatment using oxidation-reduction potential. Cohen (10) reviewed bio- filtration

  12. ON THE STAR FORMATION EFFICIENCY OF TURBULENT MAGNETIZED CLOUDS

    SciTech Connect (OSTI)

    Federrath, Christoph [Monash Centre for Astrophysics, School of Mathematical Sciences, Monash University, Vic 3800 (Australia)] [Monash Centre for Astrophysics, School of Mathematical Sciences, Monash University, Vic 3800 (Australia); Klessen, Ralf S., E-mail: christoph.federrath@monash.edu [Institut fuer Theoretische Astrophysik, Zentrum fuer Astronomie, Universitaet Heidelberg, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany)

    2013-01-20T23:59:59.000Z

    We study the star formation efficiency (SFE) in simulations and observations of turbulent, magnetized, molecular clouds. We find that the probability density functions (PDFs) of the density and the column density in our simulations with solenoidal, mixed, and compressive forcing of turbulence, sonic Mach numbers of 3-50, and magnetic fields in the super- to the trans-Alfvenic regime all develop power-law tails of flattening slope with increasing SFE. The high-density tails of the PDFs are consistent with equivalent radial density profiles, {rho}{proportional_to}r {sup -{kappa}} with {kappa} {approx} 1.5-2.5, in agreement with observations. Studying velocity-size scalings, we find that all the simulations are consistent with the observed v{proportional_to}l{sup 1/2} scaling of supersonic turbulence and seem to approach Kolmogorov turbulence with v{proportional_to}l{sup 1/3} below the sonic scale. The velocity-size scaling is, however, largely independent of the SFE. In contrast, the density-size and column density-size scalings are highly sensitive to star formation. We find that the power-law slope {alpha} of the density power spectrum, P {sub 3D}({rho}, k){proportional_to}k {sup {alpha}}, or equivalently the {Delta}-variance spectrum of the column density, {sigma}{sup 2} {sub {Delta}}({Sigma}, l) {proportional_to} l{sup -{alpha}}, switches sign from {alpha} {approx}< 0 for SFE {approx} 0 to {alpha} {approx}> 0 when star formation proceeds (SFE > 0). We provide a relation to compute the SFE from a measurement of {alpha}. Studying the literature, we find values ranging from {alpha} = -1.6 to +1.6 in observations covering scales from the large-scale atomic medium, over cold molecular clouds, down to dense star-forming cores. From those {alpha} values, we infer SFEs and find good agreement with independent measurements based on young stellar object (YSO) counts, where available. Our SFE-{alpha} relation provides an independent estimate of the SFE based on the column density map of a cloud alone, without requiring a priori knowledge of star formation activity or YSO counts.

  13. BIMA CO OBSERVATION OF EP AQUARII: THE SEMIREGULAR PULSATING STAR WITH A DOUBLE-COMPONENT LINE PROFILE

    E-Print Network [OSTI]

    Nakashima, Jun-ichi

    PROFILE Jun-ichi Nakashima1 Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West interferometric observation of EP Aqr, a semiregular pulsating star with a double-component line profile in the CO J ¼ 1­0 line. The broad component shows a flat-topped profile, and the narrow component shows

  14. The multiplicity of massive stars: A high angular resolution survey with the HST fine guidance sensor

    SciTech Connect (OSTI)

    Aldoretta, E. J.; Gies, D. R.; Henry, T. J.; Jao, W.-C.; Norris, R. P., E-mail: emily@astro.umontreal.ca, E-mail: gies@chara.gsu.edu, E-mail: thenry@chara.gsu.edu, E-mail: jao@chara.gsu.edu, E-mail: norris@chara.gsu.edu [Center for High Angular Resolution Astronomy, Department of Physics and Astronomy, Georgia State University, P. O. Box 5060, Atlanta, GA 30302-5060 (United States); and others

    2015-01-01T23:59:59.000Z

    We present the results of an all-sky survey made with the Fine Guidance Sensor on the Hubble Space Telescope to search for angularly resolved binary systems among massive stars. The sample of 224 stars is comprised mainly of Galactic O- and B-type stars and luminous blue variables, plus a few luminous stars in the Large Magellanic Cloud. The FGS TRANS mode observations are sensitive to the detection of companions with an angular separation between 0.?01 and 1.?0 and brighter than ?m=5. The FGS observations resolved 52 binary and 6 triple star systems and detected partially resolved binaries in 7 additional targets (43 of these are new detections). These numbers yield a companion detection frequency of 29% for the FGS survey. We also gathered literature results on the numbers of close spectroscopic binaries and wider astrometric binaries among the sample, and we present estimates of the frequency of multiple systems and the companion frequency for subsets of stars residing in clusters and associations, field stars, and runaway stars. These results confirm the high multiplicity fraction, especially among massive stars in clusters and associations. We show that the period distribution is approximately flat in increments of logP. We identify a number of systems of potential interest for long-term orbital determinations, and we note the importance of some of these companions for the interpretation of the radial velocities and light curves of close binaries that have third companions.

  15. Asymptotically flat black holes with scalar hair: a review

    E-Print Network [OSTI]

    Carlos A. R. Herdeiro; Eugen Radu

    2015-04-30T23:59:59.000Z

    We consider the status of black hole solutions with non-trivial scalar fields but no gauge fields, in four dimensional asymptotically flat space-times, reviewing both classical results and recent developments. We start by providing a simple illustration on the physical difference between black holes in electro-vacuum and scalar-vacuum. Next, we review no-scalar-hair theorems. In particular, we detail an influential theorem by Bekenstein and stress three key assumptions: 1) the type of scalar field equation; 2) the spacetime symmetry inheritance by the scalar field; 3) an energy condition. Then, we list regular (on and outside the horizon), asymptotically flat BH solutions with scalar hair, organizing them by the assumption which is violated in each case and distinguishing primary from secondary hair. We provide a table summary of the state of the art.

  16. Asymptotically flat black holes with scalar hair: a review

    E-Print Network [OSTI]

    Herdeiro, Carlos A R

    2015-01-01T23:59:59.000Z

    We consider the status of black hole solutions with non-trivial scalar fields but no gauge fields, in four dimensional asymptotically flat space-times, reviewing both classical results and recent developments. We start by providing a simple illustration on the physical difference between black holes in electro-vacuum and scalar-vacuum. Next, we review no-scalar-hair theorems. In particular, we detail an influential theorem by Bekenstein and stress three key assumptions: 1) the type of scalar field equation; 2) the spacetime symmetry inheritance by the scalar field; 3) an energy condition. Then, we list regular (on and outside the horizon), asymptotically flat BH solutions with scalar hair, organizing them by the assumption which is violated in each case and distinguishing primary from secondary hair. We provide a table summary of the state of the art.

  17. Plane-parallel waves as duals of the flat background

    E-Print Network [OSTI]

    Ladislav Hlavaty; Ivo Petr

    2014-12-03T23:59:59.000Z

    We give a classification of non-Abelian T-duals of the flat metric in D=4 dimensions with respect to the four-dimensional continuous subgroups of the Poincare group. After dualizing the flat background, we identify majority of dual models as conformal sigma models in plane-parallel wave backgrounds, most of them having torsion. We give their form in Brinkmann coordinates. We find, besides the plane-parallel waves, several diagonalizable curved metrics with nontrivial scalar curvature and torsion. Using the non-Abelian T-duality, we find general solution of the classical field equations for all the sigma models in terms of d'Alembert solutions of the wave equation.

  18. Wave interaction with a fixed vertical flat plate

    E-Print Network [OSTI]

    Glover, Lanny Bruce

    1985-01-01T23:59:59.000Z

    of Science in Ocean Engineering and graduated with merit in 1979. Commissioned an Ensign in the United States Navy he was selected for the Navy's Nuclear Power Program. After completing formal navy training he served onboard the USS TRUXTUN (CGN-35...) Andrew C. Vastano (Member) December )985 ABSTRACT wave Interaction with a Fixed Vertical Flat Plate. (December 1985) Lenny Bruce Glover, B. S. , United States Naval Academy Chairman of Advisory Committee: Dr. John B. Herbich The lift and drag...

  19. The Xi-transform for conformally flat space-time

    E-Print Network [OSTI]

    George Sparling

    2006-12-01T23:59:59.000Z

    The Xi-transform is a new spinor transform arising naturally in Einstein's general relativity. Here the example of conformally flat space-time is discussed in detail. In particular it is shown that for this case, the transform coincides with two other naturally defined transforms: one a two-variable transform on the Lie group SU(2, C), the other a transform on the space of null split octaves. The key properties of the transform are developed.

  20. DECOMMISSIONING CHALLENGES AT THE ROCKY FLATS ENVIRONMENTAL TECHNOLOGY SITE

    SciTech Connect (OSTI)

    Dorr, K. A.; Hoover, J.

    2002-02-25T23:59:59.000Z

    This paper presents a discussion of the demolition of the Building 788 cluster at the Rocky Flats Environmental Technology Site (RFETS) in Golden, Colorado. The Building 788 Cluster was a Resource Conservation and Recovery Act (RCRA) permitted storage facilities and ancillary structures. Topics covered include the methods employed for Project Planning, Regulatory Compliance, Waste Management, Hazard Identification, Radiological Controls, Risk Management, Field Implementation, and Cost Schedule control, and Lessons Learned and Project Closeout.

  1. Evaluation of tracking flat plate and concentrator PV systems

    SciTech Connect (OSTI)

    Lepley, T. [Phasor Energy Co., Phoenix, AZ (United States); Hammond, B.; Harris, A. [Arizona State Univ., Tempe, AZ (United States)

    1997-12-31T23:59:59.000Z

    Arizona Public Service Company has conducted side-by-side field tests of most of the leading tracking flat plate and concentrating PV technologies. The results verify the added value due to tracking, but show that additional reliability improvements are needed in most cases. Concentrator PV systems can be high performers in sunny regions. In addition, a novel inverter system design by Raytheon has demonstrated excellent performance and promises to be more reliable and have lower cost than competing technologies.

  2. Rocky Flats Plant Site Environmental Report: 1993 Highlights

    SciTech Connect (OSTI)

    Not Available

    1993-12-31T23:59:59.000Z

    The Rocky Flats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1993. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population. This section provides an overview of these topics and summarizes more comprehensive discussions found in the main text of this annual report.

  3. Flat-response x-ray-diode-detector development

    SciTech Connect (OSTI)

    Tirsell, G.

    1982-10-01T23:59:59.000Z

    In this report we discuss the design of an improved sub-nanosecond flat response x-ray diode detector needed for ICF diagnostics. This device consists of a high Z cathode and a complex filter tailored to flatten the response so that the total x-ray energy below 1.5 keV can be measured using a single detector. Three major problems have become evident as a result of our work with the original LLNL design including deviation from flatness due to a peak in the response below 200 eV, saturation at relatively low x-ray fluences, and long term gold cathode instability. We are investigating grazing incidence reflection to reduce the response below 200 eV, new high Z cathode materials for long term stability, and a new complex filter for improved flatness. Better saturation performance will require a modified XRD detector under development with reduced anode to cathode spacing and increased anode bias voltage.

  4. Asymptotically flat radiating solutions in third order Lovelock gravity

    SciTech Connect (OSTI)

    Dehghani, M. H. [Physics Department and Biruni Observatory, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Research Institute for Astrophysics and Astronomy of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Farhangkhah, N. [Physics Department and Biruni Observatory, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of)

    2008-09-15T23:59:59.000Z

    In this paper, we present an exact spherically symmetric solution of third order Lovelock gravity in n dimensions which describes the gravitational collapse of a null dust fluid. This solution is asymptotically (anti-)de Sitter or flat depending on the choice of the cosmological constant. Using the asymptotically flat solution for n{>=}7 with a power-law form of the mass as a function of the null coordinate, we present a model for a gravitational collapse in which a null dust fluid radially injects into an initially flat and empty region. It is found that a naked singularity is inevitably formed whose strength is different for the n=7 and n{>=}8 cases. In the n=7 case, the limiting focusing condition for the strength of curvature singularity is satisfied. But for n{>=}8, the strength of curvature singularity depends on the rate of increase of mass of the spacetime. These considerations show that the third order Lovelock term weakens the strength of the curvature singularity.

  5. Neutrostriction in Neutron stars

    E-Print Network [OSTI]

    V. K. Ignatovich

    2006-06-29T23:59:59.000Z

    It is demonstrated that not only gravity, but also neutrostriction forces due to optical potential created by coherent elastic neutron-neutron scattering can hold a neutron star together. The latter forces can be stronger than gravitational ones. The effect of these forces on mass, radius and structure of the neutron star is estimated.

  6. Liquid membrane coated ion-exchange column solids

    DOE Patents [OSTI]

    Barkey, Dale P. (Berkeley, CA)

    1989-01-01T23:59:59.000Z

    This invention relates to a method for improving the performance of liquid embrane separations by coating a liquid membrane onto solid ion-exchange resin beads in a fixed bed. Ion-exchange beads fabricated from an ion-exchange resin are swelled with water and are coated with a liquid membrane material that forms a film over the beads. The beads constitute a fixed bed ion-exchange column. Fluid being treated that contains the desired ion to be trapped by the ion-exchange particle is passed through the column. A carrier molecule, contained in the liquid membrane ion-exchange material, is selected for the desired ion in the fluid. The carrier molecule forms a complex with the desired ion, transporting it through the membrane and thus separating it from the other ions. The solution is fed continuously until breakthrough occurs at which time the ion is recovered, and the bed is regenerated.

  7. Liquid membrane coated ion-exchange column solids

    DOE Patents [OSTI]

    Barkey, Dale P. (Berkeley, CA)

    1988-01-01T23:59:59.000Z

    This invention relates to a method for improving the performance of liquid membrane separations by coating a liquid membrane onto solid ion-exchange resin beads in a fixed bed. Ion-exchange beads fabricated from an ion-exchange resin are swelled with water and are coated with a liquid membrane material that forms a film over the beads. The beads constitute a fixed bed ion-exchange column. Fluid being treated that contains the desired ion to be trapped by the ion-exchange particle is passed through the column. A carrier molecule, contained in the liquid membrane ion-exchange material, is selective for the desired ion in the fluid. The carrier molecule forms a complex with the desired ion, transporting it through the membrane and thus separating it from the other ions. The solution is fed continuously until breakthrough occurs at which time the ion is recovered, and the bed is regenerated.

  8. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOE Patents [OSTI]

    Burkholder, Harvey R. (Ames, IA); Fanslow, Glenn E. (Ames, IA)

    1983-01-01T23:59:59.000Z

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed.

  9. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOE Patents [OSTI]

    Burkholder, H.R.; Fanslow, G.E.

    1983-12-20T23:59:59.000Z

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed. 8 figs.

  10. 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.

  11. Electrically charged compact stars

    E-Print Network [OSTI]

    Subharthi Ray; Manuel Malheiro; Jose' P. S. Lemos; Vilson T. Zanchin

    2006-04-17T23:59:59.000Z

    We review here the classical argument used to justify the electrical neutrality of stars and show that if the pressure and density of the matter and gravitational field inside the star are large, then a charge and a strong electric field can be present. For a neutron star with high pressure (~ 10^{33} to 10^{35} dynes /cm^2) and strong gravitational field (~ 10^{14} cm/s^2), these conditions are satisfied. The hydrostatic equation which arises from general relativity, is modified considerably to meet the requirements of the inclusion of the charge. In order to see any appreciable effect on the phenomenology of the neutron stars, the charge and the electrical fields have to be huge (~ 10^{21} Volts/cm). These stars are not however stable from the viewpoint that each charged particle is unbound to the uncharged particles, and thus the system collapses one step further to a charged black hole

  12. ARM - Field Campaign - Two-Column Aerosol Project (TCAP)

    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- PolarizationgovCampaignsSummer Single Column Model

  13. Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report

    SciTech Connect (OSTI)

    W.E. Lowry

    2001-12-13T23:59:59.000Z

    The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.

  14. December 13, 2012 The steady state model of a reactive distillation column for ethylene glycol

    E-Print Network [OSTI]

    Neumaier, Arnold

    December 13, 2012 The steady state model of a reactive distillation column for ethylene glycol in an ethylene glycol reactive distillation column. Ind. Eng. Chem. Res., 33:2738­2748, 1994. 3 #12;

  15. Application of a Plantwide Control Design Procedure to a Distillation Column with Heat Pump

    E-Print Network [OSTI]

    Skogestad, Sigurd

    (Larsson & Skogestad 2001) to a distillation column heat-integrated by using a heatpump. Top-down analysis) and apply it to a distillation column with heatpump. Plantwide control design should start by formulating

  16. Preparation of Papers in Two-Column Format for Conference Proceedings Sponsored by IEEE

    E-Print Network [OSTI]

    Xie, Tao

    give you basic guidelines for preparing camera-ready papers for conference proceedings. I. INTRODUCTION column width is 88mm (3.45 in). The space between the two columns is 4mm (0.17 in). Paragraph indentation

  17. Experimental and Analytical Studies on Old Reinforced Concrete Buildings with Seismically Vulnerable Beam-Column Joints

    E-Print Network [OSTI]

    PARK, SANGJOON

    2010-01-01T23:59:59.000Z

    compression block in the beam section at the column jointcompression block in the column section at the beam jointblock Figure IV.17 Instrumentation for rotation at the beam-joint

  18. 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, ...

  19. Complete pattern of ocular dominance columns in human primary visual cortex.

    E-Print Network [OSTI]

    Adams, Daniel L; Sincich, Lawrence C; Horton, Jonathan C

    2007-01-01T23:59:59.000Z

    exhibit greater heterogeneity. dle of the cortex devoid oflarger V1 correlates with a dle of ocular dominance columns.

  20. Planets of young stars

    E-Print Network [OSTI]

    E. W. Guenther; E. Esposito

    2007-01-10T23:59:59.000Z

    Since the first massive planet in a short period orbit was discovered, the question arised how such an object could have formed. There are basically two formation scenarios: migration due to planet-disk or planet-planet interaction. Which of the two scenarios is more realistic can be found out by observing short-period planets of stars with an age between 10E7 and 10E8 yrs. The second aim of the survey is to find out how many planets originally formed, and how many of these are destroyed in the first Gyrs: Do most young, close-in planets evaporate, or spiral into the host stars? In here we report on the first results of a radial-velocity search program for planets of young stars which we began in 2004. Using HARPS, we currently monitor 85 stars with ages between 10E7 and 10E8 yrs. We show that the detection of planets of young stars is possible. Up to now, we have identified 3 planet-candidates. Taking this result together with the results of other surveys, we conclude that the frequency of massive-short period planets of young stars is not dramatically higher than that of old stars.

  1. Laboratory Glass Columns "Next Generation" technology for high-performance preparative chromatography

    E-Print Network [OSTI]

    Lebendiker, Mario

    SNAP ® Laboratory Glass Columns "Next Generation" technology for high-performance preparative lesiones graves o la muerte! WARNING Glass SNAP® columns are intended for use in a liquid environment disassembly or cleaning for scratches, chips or defects, particularly on the glass surfaces. DO NOT use column

  2. Optimal operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionation

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Optimal operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionation · The Petlyuk distillation column, see Figure 1(a), with a pre-fractionator (C1) and a main column (C21 and C22) N-7465 Trondheim, Norway Abstract This work shows the unexpected result that over-fractionating one

  3. The dos and don'ts of distillation column control Sigurd Skogestad*

    E-Print Network [OSTI]

    Skogestad, Sigurd

    The dos and don'ts of distillation column control Sigurd Skogestad* Department of Chemical discusses distillation column control within the general framework of plantwide control. In addition for distillation columns. The standard LV-configuration combined with a fast temperature loop is recommended

  4. Comparison of Alternative Control Structures for an Ideal Two-Product Reactive Distillation Column

    E-Print Network [OSTI]

    Al-Arfaj, Muhammad A.

    Comparison of Alternative Control Structures for an Ideal Two-Product Reactive Distillation Column distillation columns have been explored in many papers, very few papers have dealt with closed-loop control. Most of these control papers consider reactive distillation columns in which there is only one product

  5. THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES --WITH APPLICATION TO DISTILLATION COLUMNS

    E-Print Network [OSTI]

    Skogestad, Sigurd

    THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES --WITH APPLICATION TO DISTILLATION COLUMNS John Morud that a subsystem is influenced only by its nabor subsystems. An example of such a process is a distillation column in high purity distillation columns; in fact, the magnitude of these time constants may increase

  6. THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES WITH APPLICATION TO DISTILLATION COLUMNS

    E-Print Network [OSTI]

    Skogestad, Sigurd

    THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES WITH APPLICATION TO DISTILLATION COLUMNS John Morud that a subsystem is in uenced only by its nabor subsystems. An example of such a process is a distillation column in high purity distillation columns; in fact, the magnitude of these time constants may increase

  7. A globally convergent method for finding all steady-state solutions of distillation columns

    E-Print Network [OSTI]

    Neumaier, Arnold

    A globally convergent method for finding all steady-state solutions of distillation columns Ali distillation column with 7 steady-states show the robustness of the method. No published software known to the steady-state model of distillation columns as it returns the original system as a single large block

  8. Department of Mechanical Engineering Spring 2011 Liquid Nitrogen Packed Column Distributor Design

    E-Print Network [OSTI]

    Demirel, Melik C.

    concepts for a liquid nitrogen distributor for a packed distillation column. The design team at Penn State distillation column design. Approach The design team first gathered customer specifications from Air ProductsPENNSTATE Department of Mechanical Engineering Spring 2011 Liquid Nitrogen Packed Column

  9. Spatial distribution of isoprene emissions from North America derived from formaldehyde column measurements by the OMI satellite sensor

    E-Print Network [OSTI]

    Chance, Kelly

    Spatial distribution of isoprene emissions from North America derived from formaldehyde column isoprene emission from North America. OMI HCHO columns for June-August 2006 are consistent distribution of OMI HCHO columns follows that of isoprene emission; anthropogenic hydrocarbon emissions

  10. Rocky Flats Neutron Detector Testing at Valduc, France

    SciTech Connect (OSTI)

    Kim, S S; Dulik, G M

    2011-01-03T23:59:59.000Z

    Recent program requirements of the US Department of Energy/NNSA have led to a need for a criticality accident alarm system to be installed at a newly activated facility. The Criticality Safety Group of the Lawrence Livermore National Laboratory (LLNL) was able to recover and store for possible future use approximately 200 neutron criticality detectors and 20 master alarm panels from the former Rocky Flats Plant in Golden, Colorado when the plant was closed. The Criticality Safety Group participated in a facility analysis and evaluation, the engineering design and review process, as well as the refurbishment, testing, and recalibration of the Rocky Flats criticality alarm system equipment to be used in the new facility. In order to demonstrate the functionality and survivability of the neutron detectors to the effects of an actual criticality accident, neutron detector testing was performed at the French CEA Valduc SILENE reactor from October 7 to October 19, 2010. The neutron detectors were exposed to three criticality events or pulses generated by the SILENE reactor. The first excursion was performed with a bare or unshielded reactor, and the second excursion was made with a lead shielded/reflected reactor, and the third excursion with a polyethylene reflected core. These tests of the Rocky Flats neutron detectors were performed as a part of the 2010 Criticality Accident Alarm System Benchmark Measurements at the SILENE Reactor. The principal investigators for this series of experiments were Thomas M. Miller and John C. Wagner of the Oak Ridge National Laboratory, with Nicolas Authier and Nathalie Baclet of CEA Valduc. Several other organizations were also represented, including the Y-12 National Security Complex, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, CEA Saclay, and Babcock International Group.

  11. Entanglement entropy in Galilean conformal field theories and flat holography

    E-Print Network [OSTI]

    Arjun Bagchi; Rudranil Basu; Daniel Grumiller; Max Riegler

    2014-10-15T23:59:59.000Z

    We present the analytical calculation of entanglement entropy for a class of two dimensional field theories governed by the symmetries of the Galilean conformal algebra, thus providing a rare example of such an exact computation. These field theories are the putative holographic duals to theories of gravity in three-dimensional asymptotically flat spacetimes. We provide a check of our field theory answers by an analysis of geodesics. We also exploit the Chern-Simons formulation of three-dimensional gravity and adapt recent proposals of calculating entanglement entropy by Wilson lines in this context to find an independent confirmation of our results from holography.

  12. Radion stabilization from the vacuum on flat extra dimensions

    SciTech Connect (OSTI)

    Santos, Eli [Departamento de Fisica, Universidad Autonoma Metropolitana, Apartado Postal 55-534, C. P. 09340 Mexico, D.F. (Mexico); Secretaria Academica de Fisica y Matematicas, Fac. de Ingenieria, Universidad Autonoma de Chiapas, Calle 4a. Oriente, Norte 1428, 29000 Tuxtla Gutierrez, Chiapas (Mexico); Perez-Lorenzana, A. [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del I.P.N., Apartado Postal 14-740, 07000, Mexico, D.F. (Mexico); Pimentel, Luis O. [Departamento de Fisica, Universidad Autonoma Metropolitana, Apartado Postal 55-534, C. P. 09340 Mexico, D.F. (Mexico)

    2008-01-15T23:59:59.000Z

    Volume stabilization in models with flat extra dimensions could follow from vacuum energy residing in the bulk when translational invariance is spontaneously broken. We study a simple toy model that exemplifies this mechanism which considers a massive scalar field with nontrivial boundary conditions at the end points of the compact space, and includes contributions from brane and bulk cosmological constants. We perform our analysis in the conformal frame where the radion field, associated with volume variations, is defined, and present a general strategy for building stabilization potentials out of those ingredients. We also provide working examples for the interval and the T{sup n}/Z{sub 2} orbifold configuration.

  13. DOE - Office of Legacy Management -- Rocky Flats Petition

    Office of Legacy Management (LM)

    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 for4,645 3,625 1,006 492 742EnergyOn AprilA group currentBradleyTableSelling7111A Lithologic andRECORDDPetition Rocky Flats

  14. Final Rocky Flats Cleanup Agreement, July 19, 1996 Summary

    Office of Environmental Management (EM)

    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 for4,645 3,625 1,006 492 742 33 1112011 Strategic Plan| Departmentof Ohio Environmental Protection AgencyFinalRocky Flats Cleanup

  15. West Ford Flat Geothermal Facility | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTri GlobalJump to: navigation,Goff, 2002)WellingtonInformationFlat

  16. Windy Flats(3Q09 portion) | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat 1 Wind Project Jump to:WilsonIIa extension Jump to:Flats

  17. Property:FlatDemandStructure | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag Jump to: navigation, search Property NameFirstWellDepth JumpFlatDemandStructure

  18. East Flat Rock, North Carolina: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOE FacilityDimondale,South,Earlsboro,Canton, Ohio:Information FelicianaFlat

  19. Flat Plate PV Module Eligibility Listing Procedure Updated 6/2/14 Senate Bill 1 (SB1) defines the solar incentive programs for California, and flat plate PV

    E-Print Network [OSTI]

    Flat Plate PV Module Eligibility Listing Procedure Updated 6/2/14 Senate Bill 1 (SB1) defines the solar incentive programs for California, and flat plate PV modules 1 must be listed on the SB1 for adding PV modules to the SB1 list is as follows: 1 . Data submitted to the Energy Commission

  20. Hypernuclear Physics for Neutron Stars

    E-Print Network [OSTI]

    Jurgen Schaffner-Bielich

    2008-01-24T23:59:59.000Z

    The role of hypernuclear physics for the physics of neutron stars is delineated. Hypernuclear potentials in dense matter control the hyperon composition of dense neutron star matter. The three-body interactions of nucleons and hyperons determine the stiffness of the neutron star equation of state and thereby the maximum neutron star mass. Two-body hyperon-nucleon and hyperon-hyperon interactions give rise to hyperon pairing which exponentially suppresses cooling of neutron stars via the direct hyperon URCA processes. Non-mesonic weak reactions with hyperons in dense neutron star matter govern the gravitational wave emissions due to the r-mode instability of rotating neutron stars.

  1. Strangeness in Neutron Stars

    E-Print Network [OSTI]

    Fridolin Weber; Alexander Ho; Rodrigo P. Negreiros; Philip Rosenfield

    2006-04-20T23:59:59.000Z

    It is generally agreed on that the tremendous densities reached in the centers of neutron stars provide a high-pressure environment in which several intriguing particles processes may compete with each other. These range from the generation of hyperons to quark deconfinement to the formation of kaon condensates and H-matter. There are theoretical suggestions of even more exotic processes inside neutron stars, such as the formation of absolutely stable strange quark matter. In the latter event, neutron stars would be largely composed of strange quark matter possibly enveloped in a thin nuclear crust. This paper gives a brief overview of these striking physical possibilities with an emphasis on the role played by strangeness in neutron star matter, which constitutes compressed baryonic matter at ultra-high baryon number density but low temperature which is no accessible to relativistic heavy ion collision experiments.

  2. Masers and star formation

    E-Print Network [OSTI]

    Vincent L. Fish

    2007-04-02T23:59:59.000Z

    Recent observational and theoretical advances concerning astronomical masers in star forming regions are reviewed. Major masing species are considered individually and in combination. Key results are summarized with emphasis on present science and future prospects.

  3. Fundamental chromatographic equations designed for columns packed with very fine particles and operated at very high pressures applications to the prediction of elution times and the column efficiencies

    SciTech Connect (OSTI)

    Gritti, Fabrice [University of Tennessee, Knoxville (UTK); Guiochon, Georges A [ORNL

    2008-01-01T23:59:59.000Z

    The wall temperatures of three Acquity-BEH-C{sub 18}columns (2.1 mm x 50, 100, and 150 mm) and the temperature of the incoming eluent were maintained constant at 289 K, using a circulating water heat exchanger. The retention times and the band broadening of naphtho[2,3-a]pyrene were measured for each column as a function of the flow rate applied. Pure acetonitrile was used as the eluent. The flow rate dependence of neither elution volumes nor bandwidths can be accounted for by classical models of retention and HETP, respectively, since these models assume columns to be isothermal. Because the heat generated by friction of the eluent against the column bed increases with increasing flow rate, the column bed cannot remain isothermal at high flow rates. This heat is evacuated radially and/or longitudinally by convection, conduction, and radiation. Radial and axial temperature gradients are formed, which are maximum and minimum, respectively, when the temperature of the column wall is kept uniform and constant. The retention times that we measured match well with the values predicted based on the temperature distribution along and across the column, which we calculated and on the temperature dependence of the retention for the same column operated isothermally (i.e., at very low flow rate). The rate of band spreading varies along non-isothermal columns, so the HETP can only be defined locally. It is a function of the axial coordinate. A new contribution is needed to account for the radial thermal heterogeneity of the column, hence the radial distribution of the flow velocities, which warps the elution band. A new model, based on the general dispersion theory of Aris, allows a successful prediction of the unusually large bandwidths observed with columns packed with fine particles, operated at high flow rates, hence high inlet pressures.

  4. Analytical and Experimental Assessment of Seismic Vulnerability of Beam-Column Joints without Transverse Reinforcement in Concrete Buildings

    E-Print Network [OSTI]

    Hassan, Wael M.

    2011-01-01T23:59:59.000Z

    Deformations in Reinforced Concrete Beam–Column Joints?,P. , ?Update to ASCE/SEI 41 Concrete Provisions?, EarthquakeEffective Stiffness of Reinforced Concrete Columns?, Pacific

  5. STAR Facility Tritium Accountancy

    SciTech Connect (OSTI)

    R. J. Pawelko; J. P. Sharpe; B. J. Denny

    2007-09-01T23:59:59.000Z

    The Safety and Tritium Applied Research (STAR) facility has been established to provide a laboratory infrastructure for the fusion community to study tritium science associated with the development of safe fusion energy and other technologies. STAR is a radiological facility with an administrative total tritium inventory limit of 1.5g (14,429 Ci) [1]. Research studies with moderate tritium quantities and various radionuclides are performed in STAR. Successful operation of the STAR facility requires the ability to receive, inventory, store, dispense tritium to experiments, and to dispose of tritiated waste while accurately monitoring the tritium inventory in the facility. This paper describes tritium accountancy in the STAR facility. A primary accountancy instrument is the tritium Storage and Assay System (SAS): a system designed to receive, assay, store, and dispense tritium to experiments. Presented are the methods used to calibrate and operate the SAS. Accountancy processes utilizing the Tritium Cleanup System (TCS), and the Stack Tritium Monitoring System (STMS) are also discussed. Also presented are the equations used to quantify the amount of tritium being received into the facility, transferred to experiments, and removed from the facility. Finally, the STAR tritium accountability database is discussed.

  6. STAR facility tritium accountancy

    SciTech Connect (OSTI)

    Pawelko, R. J.; Sharpe, J. P.; Denny, B. J. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States)

    2008-07-15T23:59:59.000Z

    The Safety and Tritium Applied Research (STAR) facility has been established to provide a laboratory infrastructure for the fusion community to study tritium science associated with the development of safe fusion energy and other technologies. STAR is a radiological facility with an administrative total tritium inventory limit of 1.5 g (14,429 Ci) [1]. Research studies with moderate tritium quantities and various radionuclides are performed in STAR. Successful operation of the STAR facility requires the ability to receive, inventory, store, dispense tritium to experiments, and to dispose of tritiated waste while accurately monitoring the tritium inventory in the facility. This paper describes tritium accountancy in the STAR facility. A primary accountancy instrument is the tritium Storage and Assay System (SAS): a system designed to receive, assay, store, and dispense tritium to experiments. Presented are the methods used to calibrate and operate the SAS. Accountancy processes utilizing the Tritium Cleanup System (TCS), and the Stack Tritium Monitoring System (STMS) are also discussed. Also presented are the equations used to quantify the amount of tritium being received into the facility, transferred to experiments, and removed from the facility. Finally, the STAR tritium accountability database is discussed. (authors)

  7. Separation specifications for complex columns of minimum reflux

    E-Print Network [OSTI]

    Abdel-Aal, Hussein K

    1962-01-01T23:59:59.000Z

    slightly different foras frow those of a conventional oolumn (18). A aaterial balanoe enolos- ing the top of the column (including the side-stream Wl) and any plate ($ 1) below plate p gives g-l, i i li di, wli di"i wli (4) Siaoe J (A )(v )) Equation... (4) aay be written as follows (6) The "rectifying pinch" is given by taking the following limit. i li i li i li (7) The existence of such limit and the proof that the Equation (7) tahoe the fora( ri 1 di + wli 1 - A i at the rectifying pinch...

  8. ARM - Field Campaign - Fall 1995 Single Column Model IOP

    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(ANL-IN-03-032)8LigovCampaignsCLEX-5 CampaignSP2govCampaignsFIRE-ArcticSingle Column

  9. ARM - Field Campaign - Summer Single Column Model IOP

    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- PolarizationgovCampaignsSummer Single Column Model IOP ARM Data Discovery Browse Data

  10. Using Surface Impedance for Calculating Wakefields in Flat Geometry

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

    Bane, Karl; Stupakov, Gennady

    2015-03-01T23:59:59.000Z

    Beginning with Maxwell's equations and assuming only that the wall interaction can be approximated by a surface impedance, we derive formulas for the generalized longitudinal and transverse impedance in flat geometry, from which the wakefields can also be obtained. From the generalized impedances, by taking the proper limits, we obtain the normal longitudinal, dipole, and quad impedances in flat geometry. These equations can be applied to any surface impedance, such as the known dc, ac, and anomalous skin models of wall resistance, a model of wall roughness, or one for a pipe with small, periodic corrugations. We show that, formore »the particular case of dc wall resistance, the longitudinal impedance obtained here agrees with a known result in the literature, a result that was derived from a very general formula by Henke and Napoly. As concrete example, we apply our results to representative beam and machine parameters in the undulator region of LCLS-II and estimate the impact of the transverse wakes on the machine performance.« less

  11. Geologic and geotechnical assessment RFETS Building 371, Rocky Flats, Colorado

    SciTech Connect (OSTI)

    Maryak, M.E.; Wyatt, D.E.; Bartlett, S.F.; Lewis, M.R.; Lee, R.C.

    1995-12-13T23:59:59.000Z

    This report describes the review and evaluation of the geological, geotechnical and geophysical data supporting the design basis analysis for the Rocky Flats Environmental Test Site (RFETS) Building 371. The primary purpose of the geologic and geotechnical reviews and assessments described herein are to assess the adequacy of the crustal and near surface rock and soil model used in the seismic analysis of Building 371. This review was requested by the RFETS Seismic Evaluation Program. The purpose was to determine the adequacy of data to support the design basis for Building 371, with respect to seismic loading. The objectives required to meet this goal were to: (1) review techniques used to gather data (2) review analysis and interpretations of the data; and (3) make recommendations to gather additional data if required. Where there were questions or inadequacies in data or interpretation, recommendations were made for new data that will support the design basis analysis and operation of Building 371. In addition, recommendations are provided for a geologic and geophysical assessment for a new facility at the Rocky Flats Site.

  12. Using Surface Impedance for Calculating Wakefields in Flat Geometry

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

    Bane, Karl; Stupakov, Gennady

    2015-03-01T23:59:59.000Z

    Beginning with Maxwell's equations and assuming only that the wall interaction can be approximated by a surface impedance, we derive formulas for the generalized longitudinal and transverse impedance in flat geometry, from which the wakefields can also be obtained. From the generalized impedances, by taking the proper limits, we obtain the normal longitudinal, dipole, and quad impedances in flat geometry. These equations can be applied to any surface impedance, such as the known dc, ac, and anomalous skin models of wall resistance, a model of wall roughness, or one for a pipe with small, periodic corrugations. We show that, for the particular case of dc wall resistance, the longitudinal impedance obtained here agrees with a known result in the literature, a result that was derived from a very general formula by Henke and Napoly. As concrete example, we apply our results to representative beam and machine parameters in the undulator region of LCLS-II and estimate the impact of the transverse wakes on the machine performance.

  13. Minimization of effluent discharge to the Soil Column

    SciTech Connect (OSTI)

    Dronen, V.R.; Hydzik, K.M.

    1994-01-01T23:59:59.000Z

    In 1987, the US Congress mandated that the US Department of Energy (DOE), cease discharge of contaminated effluents to the soil column at the Hanford Site by calendar year 1995. The plan and schedule for this activity can be found in The Plan and Schedule to Discontinue Disposal of Contaminated Liquid into the Soil Column at the Hanford Site, (WHC 1987). Coupled with this mandate and DOE`s intent to cleanup Hanford (remediate and restore to the extent practicable), DOE entered into an agreement with the US Environmental Protection Agency (EPA) and the Washington State Department of Ecology (Ecology). The agreement is called the ``Hanford Federal Facility Agreement and Consent Order`` (Ecology et al. 1992) otherwise known as the Tri-Party Agreement. The Tri-Party Agreement established schedules and legally enforceable milestones for the Hanford cleanup mission. One such milestone was to cease discharge of effluent to Hanford`s 300 Area process trenches located approximately 100 m from the Columbia River, north of Richland, Washington.

  14. The Two-Column Aerosol Project (TCAP) Science Plan

    SciTech Connect (OSTI)

    Berkowitz, CM; Berg, LK; Cziczo, DJ; Flynn, CJ; Kassianov, EI; Fast, JD; Rasch, PJ; Shilling, JE; Zaveri, RA; Zelenyuk, A; Ferrare, RA; Hostetler, CA; Cairns, B; Russell, PB; Ervens, B

    2011-07-27T23:59:59.000Z

    The Two-Column Aerosol Project (TCAP) field campaign will provide a detailed set of observations with which to (1) perform radiative and cloud condensation nuclei (CCN) closure studies, (2) evaluate a new retrieval algorithm for aerosol optical depth (AOD) in the presence of clouds using passive remote sensing, (3) extend a previously developed technique to investigate aerosol indirect effects, and (4) evaluate the performance of a detailed regional-scale model and a more parameterized global-scale model in simulating particle activation and AOD associated with the aging of anthropogenic aerosols. To meet these science objectives, the Atmospheric Radiation Measurement (ARM) Climate Research Facility will deploy the ARM Mobile Facility (AMF) and the Mobile Aerosol Observing System (MAOS) on Cape Cod, Massachusetts, for a 12-month period starting in the summer of 2012 in order to quantify aerosol properties, radiation, and cloud characteristics at a location subject to both clear and cloudy conditions, and clean and polluted conditions. These observations will be supplemented by two aircraft intensive observation periods (IOPs), one in the summer and a second in the winter. Each IOP will deploy one, and possibly two, aircraft depending on available resources. The first aircraft will be equipped with a suite of in situ instrumentation to provide measurements of aerosol optical properties, particle composition and direct-beam irradiance. The second aircraft will fly directly over the first and use a multi-wavelength high spectral resolution lidar (HSRL) and scanning polarimeter to provide continuous optical and cloud properties in the column below.

  15. Strangeness in Neutron Stars

    E-Print Network [OSTI]

    Fridolin Weber

    2000-08-23T23:59:59.000Z

    It is generally agreed on that the tremendous densities reached in the centers of neutron stars provide a high-pressure environment in which numerous novel particles processes are likely to compete with each other. These processes range from the generation of hyperons to quark deconfinement to the formation of kaon condensates and H-matter. There are theoretical suggestions of even more exotic processes inside neutron stars, such as the formation of absolutely stable strange quark matter, a configuration of matter even more stable than the most stable atomic nucleus, iron. In the latter event, neutron stars would be largely composed of pure quark matter, eventually enveloped in a thin nuclear crust. No matter which physical processes are actually realized inside neutron stars, each one leads to fingerprints, some more pronounced than others though, in the observable stellar quantities. This feature combined with the unprecedented progress in observational astronomy, which allows us to see vistas with remarkable clarity that previously were only imagined, renders neutron stars to nearly ideal probes for a wide range of physical studies, including the role of strangeness in dense matter.

  16. Dark Stars: A Review

    E-Print Network [OSTI]

    Freese, Katherine; Spolyar, Douglas; Valluri, Monica

    2015-01-01T23:59:59.000Z

    Dark Stars (DS) are stellar objects made (almost entirely) of ordinary atomic material but powered by the heat from Dark Matter (DM) annihilation (rather than by fusion). Weakly Interacting Massive Particles (WIMPs), among the best candidates for DM, can be their own antimatter and can accumulate inside the star, with their annihilation products thermalizing with and heating the DS. The resulting DSs are in hydrostatic and thermal equilibrium. The first phase of stellar evolution in the history of the Universe may have been dark stars. Though DM constituted only $10^6 M_\\odot$), very bright ($>10^9 L_\\odot$), and potentially detectable with the James Webb Space Telescope (JWST). Once the DM runs out and the dark star dies, it may collapse to a black hole; thus DSs can provide seeds for the supermassive black holes observed throughout the Universe and at early times. Other sites for dark star formation exist in the Universe today in regions of high dark matter density such as the centers of galaxies. The curre...

  17. Sitewide risk perspectives for the Rocky Flats Environmental Technology Site

    SciTech Connect (OSTI)

    Olinger, S.J. [Dept. of Energy, Golden, CO (United States). Rocky Flats Field Office; Foppe, T.L. [M.H. Chew and Associates, Inc., Golden, CO (United States)

    1998-05-01T23:59:59.000Z

    The US Department of Energy (DOE) has recently finalized a closure plan (originally called the Ten Year Plan) for closure and environmental cleanup of previous nuclear weapons facilities. The DOE Rocky Flats Field Office has established priorities for risk reduction work to Support closure activities, as well as addressing those hazards associated with storage and management of radioactive materials and hazardous chemicals. To provide information for future National Environmental Policy Act (NEPA) or other regulatory assessments of specific risk reduction projects identified in the Closure Plan, a risk assessment of normal operations and potential accidents was recently prepared to provide an updated baseline of the cumulative impacts to the worker, public and environment due to the Site`s operations, activities, and environmental conditions in light of the Site`s change in mission, and of future closure projects. This paper summarizes the risk assessment approach, results, and conclusions.

  18. Epidemiologic surveillance. Annual report for EG&G Rocky Flats

    SciTech Connect (OSTI)

    NONE

    1994-12-31T23:59:59.000Z

    Epidemiologic surveillance at U.S. Department of Energy (DOE) facilities consists of regular and systematic collection, analysis, and interpretation of data on absences resulting from illness and injury in the work force. Its purpose is to provide an early warning system for health problems occurring among employees at participating sites. Data are collected by coordinators at each site and submitted to the Epidemiologic Surveillance Data Center, located at the Oak Ridge Institute for Science and Education, where quality control procedures and analyses are carried out. Rates of absences and rates of diagnoses associated with absences are analyzed by occupation and other relevant variables. They may be compared with the disease experience of different groups within the DOE work force and with populations that do not work for DOE to identify disease patterns or clusters that may be associated with work activities. This report presents the 1994 morbidity data for the Rocky Flats plant.

  19. System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report

    SciTech Connect (OSTI)

    Freeman, J.; Whitmore, J.; Kaffine, L.; Blair, N.; Dobos, A. P.

    2013-12-01T23:59:59.000Z

    The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.

  20. Majorana Flat Bands in s-Wave Gapless Topological Superconductors

    E-Print Network [OSTI]

    Shusa Deng; Gerardo Ortiz; Amrit Poudel; Lorenza Viola

    2014-04-28T23:59:59.000Z

    We demonstrate how the non-trivial interplay between spin-orbit coupling and nodeless $s$-wave superconductivity can drive a fully gapped two-band topological insulator into a time-reversal invariant gapless topological superconductor supporting symmetry-protected Majorana flat bands. We characterize topological phase diagrams by a ${\\mathbb Z}_2 \\times{\\mathbb Z}_2$ partial Berry-phase invariant, and show that, despite the trivial crystal geometry, no unique bulk-boundary correspondence exists. We trace this behavior to the anisotropic quasiparticle bulk gap closing, linear vs. quadratic, and argue that this provides a unifying principle for gapless topological superconductivity. Experimental implications for tunneling conductance measurements are addressed, relevant for lead chalcogenide materials.

  1. Improving the diversity of manufacturing electroluminescent flat panel displays

    SciTech Connect (OSTI)

    Moss, T.S.; Samuels, J.A.; Smith, D.C. [and others

    1995-09-01T23:59:59.000Z

    Crystalline calcium thiogallate with a cerium dopant has been deposited by metal-organic chemical vapor deposition (MOCVD) at temperatures below 600{degrees}C on a low cost glass substrate. An EL luminance of 1.05 fL was observed 40 volts above threshold at 60 Hz. This is more than an order of magnitude improvement over earlier crystalline-as-deposited thiogallate materials. These results pave the way for the use of MOCVD as a potential method for processing full color thin-film electroluminescent (TFEL) flat panel displays. The formation of the CaGa{sub 2}S{sub 4}:Ce phosphor requires precise control over a number of deposition parameters including flow rates, substrate temperature, and reactor pressure. The influence of these parameters will be discussed in terms of structure, uniformity, and TFEL device performance.

  2. Diffractive optics for compact flat panel displays. Final report

    SciTech Connect (OSTI)

    Sweeney, D.; DeLong, K.

    1997-04-29T23:59:59.000Z

    Three years ago LLNL developed a practical method to dramatically reduce the chromatic aberration in single element diffractive imaging lenses. High efficiency, achromatic imaging lenses have been fabricated for human vision correction. This LDRD supported research in applying our new methods to develop a unique, diffraction-based optical interface with solid state, microelectronic imaging devices. Advances in microelectronics have led to smaller, more efficient components for optical systems. There have, however, been no equivalent advances in the imaging optics associated with these devices. The goal of this project was to replace the bulky, refractive optics in typical head-mounted displays with micro-thin diffractive optics to directly image flat-panel displays into the eye. To visualize the system think of the lenses of someone`s eyeglasses becoming flat-panel displays. To realize this embodiment, we needed to solve the problems of large chromatic aberrations and low efficiency that are associated with diffraction. We have developed a graceful tradeoff between chromatic aberrations and the diffractive optic thickness. It turns out that by doubling the thickness of a micro-thin diffractive lens we obtain nearly a two-times improvement in chromatic performance. Since the human eye will tolerate one diopter of chromatic aberration, we are able to achieve an achromatic image with a diffractive lens that is only 20 microns thick, versus 3 mm thickness for the comparable refractive lens. Molds for the diffractive lenses are diamond turned with sub-micron accuracy; the final lenses are cast from these molds using various polymers. We thus retain both the micro- thin nature of the diffractive optics and the achromatic image quality of refractive optics. During the first year of funding we successfully extended our earlier technology from 1 cm diameter optics required for vision applications up to the 5 cm diameter optics required for this application. 3 refs., 6 figs.

  3. The Planck quantum hypothesis and the Friedmannian models of flat universe

    E-Print Network [OSTI]

    V. Skalsky

    2000-09-25T23:59:59.000Z

    Only one model from an infinite number of the Friedmannian models of flat expansive isotropic and homogeneous universe satisfies the assumptions resulting from the Planck quantum hypothesis.

  4. amorphous selenium flat-panel: Topics by E-print Network

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

    and organic Heikenfeld, Jason 12 Asymmetric electrical properties of fork a-Si:H thin-film transistor and its application to flat panel displays Mathematics Websites Summary:...

  5. E-Print Network 3.0 - amorphous selenium flat Sample Search Results

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

    on a-Se direct conversion detector Summary: ). The digital detector consists of a flat panel using the amorphous selenium technology (ANRAD Corporation... : the most promising are...

  6. amorphous silicon flat-panel: Topics by E-print Network

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

    5 Asymmetric Electrical Properties of Half Corbino Hydrogenated Amorphous Silicon Thin-Film Transistor and Its Applications to Flat Panel Displays Materials Science...

  7. Flat space cosmologies in two dimensions - Phase transitions and asymptotic mass-domination

    E-Print Network [OSTI]

    Arjun Bagchi; Daniel Grumiller; Jakob Salzer; Sourav Sarkar; Friedrich Schöller

    2014-08-22T23:59:59.000Z

    We study flat space cosmologies in two dimensions by taking the flat space limit of the Achucarro-Ortiz model. We unravel a phase transition between hot flat space and flat space cosmologies, and derive a new dilaton-dependent counterterm required for the consistency of the Euclidean partition function. Our results generalize to asymptotically mass-dominated 2-dimensional dilaton gravity models, whose thermodynamical properties we discuss. The novel case of asymptotic mass-domination is neither covered by the comprehensive discussion of hep-th/0703230 nor by the more recent generalization to dilaton gravity with confining U(1) charges in 1406.7007.

  8. Small Column Ion Exchange Design and Safety Strategy

    SciTech Connect (OSTI)

    Huff, T.; Rios-Armstrong, M.; Edwards, R.; Herman, D.

    2011-02-07T23:59:59.000Z

    Small Column Ion Exchange (SCIX) is a transformational technology originally developed by the Department of Energy (DOE) Environmental Management (EM-30) office and is now being deployed at the Savannah River Site (SRS) to significantly increase overall salt processing capacity and accelerate the Liquid Waste System life-cycle. The process combines strontium and actinide removal using Monosodium Titanate (MST), Rotary Microfiltration, and cesium removal using Crystalline Silicotitanate (CST, specifically UOP IONSIV{reg_sign}IE-911 ion exchanger) to create a low level waste stream to be disposed in grout and a high level waste stream to be vitrified. The process also includes preparation of the streams for disposal, e.g., grinding of the loaded CST material. These waste processing components are technically mature and flowsheet integration studies are being performed including glass formulations studies, application specific thermal modeling, and mixing studies. The deployment program includes design and fabrication of the Rotary Microfilter (RMF) assembly, ion-exchange columns (IXCs), and grinder module, utilizing an integrated system safety design approach. The design concept is to install the process inside an existing waste tank, Tank 41H. The process consists of a feed pump with a set of four RMFs, two IXCs, a media grinder, three Submersible Mixer Pumps (SMPs), and all supporting infrastructure including media receipt and preparation facilities. The design addresses MST mixing to achieve the required strontium and actinide removal and to prevent future retrieval problems. CST achieves very high cesium loadings (up to 1,100 curies per gallon (Ci/gal) bed volume). The design addresses the hazards associated with this material including heat management (in column and in-tank), as detailed in the thermal modeling. The CST must be size reduced for compatibility with downstream processes. The design addresses material transport into and out of the grinder and includes provisions for equipment maintenance including remote handling. The design includes a robust set of nuclear safety controls compliant with DOE Standard (STD)-1189, Integration of Safety into the Design Process. The controls cover explosions, spills, boiling, aerosolization, and criticality. Natural Phenomena Hazards (NPH) including seismic event, tornado/high wind, and wildland fire are considered. In addition, the SCIX process equipment was evaluated for impact to existing facility safety equipment including the waste tank itself. SCIX is an innovative program which leverages DOE's technology development capabilities to provide a basis for a successful field deployment.

  9. Pre-main sequence stars, emission stars and recent star formation in the Cygnus Region

    E-Print Network [OSTI]

    Bhavya B; Blesson Mathew; Annapurni Subramaniam

    2008-04-09T23:59:59.000Z

    The recent star formation history in the Cygnus region is studied using 5 clusters (IC 4996, NGC 6910, Berkeley 87, Biurakan 2 and Berkeley 86). The optical data from the literature are combined with the 2MASS data to identify the pre-main sequence (pre-MS) stars as stars with near IR excess. We identified 93 pre-MS stars and 9 stars with H$_\\alpha$ emission spectra. The identified pre-MS stars are used to estimate the turn-on age of the clusters. The duration of star formation was estimated as the difference between the turn-on and the turn-off age. We find that, NGC 6910 and IC 4996 have been forming stars continuously for the last 6 -- 7 Myr, Berkeley 86 and Biurakan 2 for 5 Myr and Berkeley 87 for the last 2 Myr. This indicates that the Cygnus region has been actively forming stars for the last 7 Myr, depending on the location. 9 emission line stars were identified in 4 clusters, using slit-less spectra (Be 87 - 4 stars; Be 86 - 2 stars, NGC 6910 - 2 stars and IC 4996 - 1 star). The individual spectra were obtained and analysed to estimate stellar as well as disk properties. All the emission stars are in the MS, well below the turn-off, in the core hydrogen burning phase. These stars are likely to be Classical Be (CBe) stars. Thus CBe phenomenon can be found in very young MS stars which are just a few (2 -- 7) Myrs old. This is an indication that CBe phenomenon need not be an evolutionary effect.

  10. Spectropolarimetry of cool stars

    E-Print Network [OSTI]

    P. Petit

    2007-03-27T23:59:59.000Z

    In recent years, the development of spectropolarimetric techniques deeply modified our knowledge of stellar magnetism. In the case of solar-type stars, the challenge is to measure a geometrically complex field and determine its evolution over very different time frames. In this article, I summarize some important observational results obtained in this field over the last two decades and detail what they tell us about the dynamo processes that orchestrate the activity of cool stars. I also discuss what we learn from such observations about the ability of magnetic fields to affect the formation and evolution of Sun-like stars. Finally, I evoke promising directions to be explored in the coming years, thanks to the advent of a new generation of instruments specifically designed to progress in this domain.

  11. Measurement Reconciliation and Interpretation in Packed Distillation Column Operation Teck C. Lee and Colin S. Howat, Ph.D.

    E-Print Network [OSTI]

    Howat, Colin S. "Chip"

    . To overcome this limitation, a pilot plant scale, packed distillation column was designed, built, and tested plant scale, packed distillation column was designed, built, and tested. This column can be operatedMeasurement Reconciliation and Interpretation in Packed Distillation Column Operation Teck C. Lee

  12. Isolating Triggered Star Formation

    SciTech Connect (OSTI)

    Barton, Elizabeth J.; Arnold, Jacob A.; /UC, Irvine; Zentner, Andrew R.; /KICP, Chicago /Chicago U., EFI; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo

    2007-09-12T23:59:59.000Z

    Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to 'field' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than 'field' galaxies is primarily a selection effect. We use our simulations to devise a means to select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N= 2 halos) and to select a control sample of isolated galaxies (N= 1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M{sub B,j} {le} -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5 %) of these L* and sub-L* galaxies in isolated 50 (30) h{sup -1} kpc pairs exhibit star formation that is boosted by a factor of {approx}> 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. Our orbit models suggest that 12% (16%) of 50 (30) h{sup -1} kpc close pairs that are isolated according to our definition have had a close ({le} 30 h{sup -1} kpc) pass within the last Gyr. Thus, the data are broadly consistent with a scenario in which most or all close passes of isolated pairs result in triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding the importance of triggered star formation in a cosmological context.

  13. Synthetic guide star generation

    DOE Patents [OSTI]

    Payne, Stephen A.; Page, Ralph H.; Ebbers, Christopher A.; Beach, Raymond J.

    2004-03-09T23:59:59.000Z

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  14. Synthetic guide star generation

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA) [Castro Valley, CA; Page, Ralph H. (Castro Valley, CA) [Castro Valley, CA; Ebbers, Christopher A. (Livermore, CA) [Livermore, CA; Beach, Raymond J. (Livermore, CA) [Livermore, CA

    2008-06-10T23:59:59.000Z

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  15. A Star on Earth

    ScienceCinema (OSTI)

    Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

    2014-06-06T23:59:59.000Z

    At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

  16. A Star on Earth

    SciTech Connect (OSTI)

    Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

    2014-03-05T23:59:59.000Z

    At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

  17. Evaluation of fluoride-induced metal mobilization in soil columns

    SciTech Connect (OSTI)

    Totsche, K.U.; Wilcke, W.; Koerber, M.; Kobza, J.; Zech, W.

    2000-04-01T23:59:59.000Z

    Fluoride in soil solution may cause substantially increased leaching of dissolved organic carbon (DOC), Al, and heavy metals from soils. The authors objective was to examine whether increased metal solubility is attributable to formation of fluoro- or organo-complexes. The A horizon of a Slovak soil contaminated with heavy metals and F by Al smelter emissions was used to conduct two column experiments under saturated and steady-state water flow conditions. The columns were leached with 5 mM Na{sub 2}SO{sub 4}, 1 mM NaCl, and 9 mM NaF solutions at pH 5.5 and an electrical conductivity of 1,000 {micro}S cm{sup {minus}1}. Samples were collected in 70-min intervals for approximately 7 d. Two experiments were performed. In the first experiment (single F pulse), a fluoride (F) pulse was applied for 36 pore volumes (PVs), while in the second experiment (dual F pulse), two consecutive F pulses (each for 2.8 PVs) were applied. For both experiments, Cl breakthrough curves (BTCs) revealed a convection-dominated transport regime. The breakthrough of Cd, Cr, Fe, Ni, and Pb paralleled DOC breakthrough in both experiments indicating metal leaching as organocomplex. In the dual F pulse experiment, peak separation of the DOC and the complexed F (F{sub bound}) breakthrough was achieved. The highest F{sub bound} concentration occurred 3.8 PVs later than that of DOC. The AlBTC paralleled that of F{sub bound} but showed tailing with a turning point simultaneous to the highest DOC concentration. Thus, the increase in Al solubility was mainly caused by fluoro-complexation and only to a lesser extent by organo-complexation.

  18. CFL Manufacturers: ENERGY STAR Letters

    Broader source: Energy.gov [DOE]

    DOE issued letters to 25 manufacturers of compact fluorescent lamps (CFLs) involving various models after PEARL Cycle 9 testing indicated that the models do not meet the ENERGY STAR specification and, therefore, are disqualified from the ENERGY STAR Program.

  19. Lithium in LMC carbon stars

    E-Print Network [OSTI]

    D. Hatzidimitriou; D. H. Morgan; R. D. Cannon; B. F. W. Croke

    2003-04-16T23:59:59.000Z

    Nineteen carbon stars that show lithium enrichment in their atmospheres have been discovered among a sample of 674 carbon stars in the Large Magellanic Cloud. Six of the Li-rich carbon stars are of J-type, i.e. with strong 13C isotopic features. No super-Li-rich carbon stars were found. The incidence of lithium enrichment among carbon stars in the LMC is much rarer than in the Galaxy, and about five times more frequent among J-type than among N-type carbon stars. The bolometric magnitudes of the Li-rich carbon stars range between -3.3 and -5.7. Existing models of Li-enrichment via the hot bottom burning process fail to account for all of the observed properties of the Li-enriched stars studied here.

  20. Improving the Performance of a Two-Shell Column with Advanced Control

    E-Print Network [OSTI]

    Morrison, T. A.; Laflamme, D.

    IMPROVING THE PERFORMANCE OF A TWO-SHELL COLUMN WITH ADVANCED CONTROL TIMOTHY A. MORRISON SENIOR PROJECT ENGINEER SETPOINT Inc. Houston, Texas ABSTRACT Application of advanced control techniques to a two-shell, two- pressure distillation... column has yielded stable operation with reduced utility consumption and increased capacity. Prior to the application of advanced controls this column was a plant capacity limit and composition control was very difficult. The advanced controls now...

  1. Influence of viscous friction heating on the efficiency of columns operated under very high pressures

    SciTech Connect (OSTI)

    Gritti, Fabrice [University of Tennessee, Knoxville (UTK); Guiochon, Georges A [ORNL

    2009-01-01T23:59:59.000Z

    When columns packed with very fine particles are operated at high mobile phase velocities, the friction of the mobile phase percolating through the column bed generates heat. This heat dissipates along and across the column and axial and radial temperature gradients appear. The wall region of the column tends to be cooler than its center, and due to the influence of temperature on the mobile phase viscosity and on the equilibrium constant of analytes, the band velocity is not constant across the column. This radial heterogeneity of the temperature distribution across the column contributes to band broadening. This phenomenon was investigated assuming a cylindrically symmetrical column and using the general dispersion theory of Aris, which relates the height equivalent to the theoretical plate (HETP) contribution due to a radial heterogeneity of the column to the radial distribution of the linear velocities of a compound peak and to the radial distribution of its apparent dispersion coefficients in the column bed. The former is known from the temperature gradient across the column, the temperature dependencies of the mobile phase viscosity, and the retention factor of the compound. The latter is derived from the known expression of the transverse reduced HETP equation for the column. The values of the HETP calculated with the Aris model and a classical HETP equation were compared to those measured on a 2.1 x 50 mm Acquity BEH-C{sub 18} column, run at flow rates of 0.6, 0.95, 1.30, and 1.65 mL/min, with pure acetonitrile as the mobile phase and naphtho[2,3-a]pyrene as the retained compound. These two sets of data are in generally good agreement, although the experimental values of the HETP tend to increase faster with increasing mobile phase velocity than the calculated values.

  2. anion-exchange column chromatography: Topics by E-print Network

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

    BDNF 12 Grossberg, Stephen 339 The impact of technical specifications on the life cycle costs of process columns in petrochemical facilities. Open Access Theses and...

  3. Testing and analysis of structural steel columns subjected to blast loads

    E-Print Network [OSTI]

    Stewart, Lauren K.

    2010-01-01T23:59:59.000Z

    to simulate a testing series on concrete masonry walls suchand testing for steel columns with a simplified boundary design of a concrete

  4. A new warmstarting strategy for the primal-dual column generation ...

    E-Print Network [OSTI]

    Jacek Gondzio

    2012-06-24T23:59:59.000Z

    Jun 24, 2012 ... Abstract: This paper presents a new warmstarting technique in the context of a primal-dual column generation method applied to solve a ...

  5. Improved Design Tools for Surface Water and Standing Column Well Heat Pump Systems

    Broader source: Energy.gov [DOE]

    This project will improve the capability of engineers to design heat pump systems that utilize surface water or standing column wells (SCW) as their heat sources and sinks.

  6. High-gravity central stars

    E-Print Network [OSTI]

    Thomas Rauch

    2006-07-11T23:59:59.000Z

    NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

  7. Energy generation in stars

    E-Print Network [OSTI]

    B. V. Vasiliev

    2001-10-29T23:59:59.000Z

    It is a current opinion that thermonuclear fusion is the main source of the star activity. It is shown below that this source is not unique. There is another electrostatic mechanism of the energy generation which accompanies thermonuclear fusion. Probably, this approach can solve the solar neutrino problem.

  8. The Abundance of Fluorine in Normal G and K Stars of the Galactic Thin Disk

    E-Print Network [OSTI]

    Pilachowski, Catherine A

    2015-01-01T23:59:59.000Z

    The abundance of fluorine is determined from the (2-0) R9 2.3358 micron feature of the molecule HF for several dozen normal G and K stars in the Galactic thin disk from spectra obtained with the Phoenix IR spectrometer on the 2.1-m telescope at Kitt Peak. The abundances are analyzed in the context of Galactic chemical evolution to explore the contributions of supernovae and asymptotic giant branch (AGB) stars to the abundance of fluorine in the thin disk. The average abundance of fluorine in the thin disk is found to be [F/Fe] = +0.23 +/- 0.03, and the [F/Fe] ratio is flat or declines slowly with metallicity in the range from -0.6 supernovae contributes significantly to the Galactic fluorine abundance, although contributions from AGB stars may also be important.

  9. Envelope density pattern around wide binary AGB stars: a dynamical model

    E-Print Network [OSTI]

    J. H. He

    2007-03-26T23:59:59.000Z

    The goal is to build up a simple dynamical model for the out-flowing circumstellar envelope around AGB stars in a wide binary system to explore the parameter dependence of the geometrical characteristics of column density patterns. An AGB star in a wide binary system is considered as a 3-D piston model that can induce a 3-D quasi-spherical density structure in the circumstellar envelope by orbital motion of the AGB star. The column density pattern only depends on two parameters: eccentricity of the orbit e and the terminal outflow velocity to mean orbital velocity ratio gamma. When viewed perpendicular to the orbital plane, spiral, broken spiral, and incomplete concentric shell patterns can be seen, while when viewed along the orbital plane, alternative concentric half-shell, egg-shell, and half-shell half-gap patterns will develop. Non-zero eccentricity causes asymmetry, while larger gamma makes a weaker pattern and helps bring out asymmetry. A spiral pattern may becomes broken when e > 0.4. The spiral center is always less than 12% of spiral pitch away from the orbit center. One should have more chances (~ 80%) seeing spiral-like patterns than seeing concentric shells (~ 20%) in the circumstellar envelope of wide binary AGB stars.

  10. Learning Manifolds with K-Means and K-Flats Guille D. Canas ,

    E-Print Network [OSTI]

    Poggio, Tomaso

    Learning Manifolds with K-Means and K-Flats Guille D. Canas , Tomaso Poggio , Lorenzo A. Rosasco samples. In particular, we consider piecewise constant and piecewise linear estima- tors induced by k-means and k-flats, and analyze their performance. We extend previous results for k-means in two separate

  11. Holographic Dark Energy with Time Varying n^2 Parameter in Non-Flat Universe

    E-Print Network [OSTI]

    Bushra Majeed; Mubasher Jamil; Azad A. Siddiqui

    2014-11-01T23:59:59.000Z

    We consider a holographic dark energy model, with a varying parameter, n, which evolves slowly with time. We obtain the differential equation describing evolution of the dark energy density parameter, $\\Omega_d$, for the flat and non-flat FRW universes. The equation of state parameter in this generalized version of holographic dark energy depends on n.

  12. DUST EXTINCTION BIAS IN THE COLUMN DENSITY DISTRIBUTION OF GAMMA-RAY BURSTS: HIGH COLUMN DENSITY, LOW-REDSHIFT GRBs ARE MORE HEAVILY OBSCURED

    SciTech Connect (OSTI)

    Watson, Darach [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Jakobsson, Pall, E-mail: darach@dark-cosmology.dk, E-mail: pja@raunvis.hi.is [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhaga 5, IS-107 Reykjavik (Iceland)

    2012-08-01T23:59:59.000Z

    The afterglows of gamma-ray bursts (GRBs) have more soft-X-ray absorption than expected from the foreground gas column in the Galaxy. While the redshift of the absorption can in general not be constrained from current X-ray observations, it has been assumed that the absorption is due to metals in the host galaxy of the GRB. The large sample of X-ray afterglows and redshifts now available allows the construction of statistically meaningful distributions of the metal column densities. We construct such a sample and show, as found in previous studies, that the typical absorbing column density (N{sub H{sub X}}) increases substantially with redshift, with few high column density objects found at low-to-moderate redshifts. We show, however, that when highly extinguished bursts are included in the sample, using redshifts from their host galaxies, high column density sources are also found at low-to-moderate redshift. We infer from individual objects in the sample and from observations of blazars that the increase in column density with redshift is unlikely to be related to metals in the intergalactic medium or intervening absorbers. Instead we show that the origin of the apparent increase with redshift is primarily due to dust extinction bias: GRBs with high X-ray absorption column densities found at z {approx}< 4 typically have very high dust extinction column densities, while those found at the highest redshifts do not. It is unclear how such a strongly evolving N{sub H{sub X}}/A{sub V} ratio would arise, and based on current data, remains a puzzle.

  13. Environmental Survey preliminary report, Rocky Flats Plant, Golden, Colorado

    SciTech Connect (OSTI)

    Not Available

    1987-06-01T23:59:59.000Z

    This report presents the preliminary findings of the Environmental Survey of the United States Department of Energy (DOE), Rocky Flats Plant (RFP), conducted August 11 through 22, 1986. The Survey is being conducted by an multidisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual team members are outside experts supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with the RFP. The Survey covers all environmental media and all areas of environmental regulations. It is being performed in accordance with the DOE Environmental Survey Manual. The on-site phase of the Survey involves the review of existing site environmental data observations of the operations carried on at RFP, and interviews with site personnel. The Survey team developed a Sampling and Analysis Plan to assist in further assessing certain environmental problems identified during its on-site activates. The Sampling and Analysis Plan is being executed by DOE's Oak Ridge National Laboratory. When completed, the results will be incorporated into the RFP Environmental Survey Interim Report. The Interim Report will reflect the final determinations of the RFP Survey. 75 refs., 24 figs., 33 tabs.

  14. Seismic equipment qualification at Rocky Flats Plant: Lessons learned

    SciTech Connect (OSTI)

    Peregoy, W.; Herring, K.

    1993-08-01T23:59:59.000Z

    Seismic equipment qualification is being evaluated as a part of the Systematic Evaluation Program (SEP) at Rocky Flats Plant (RFP). Initially it was believed that the experience database developed by the Seismic Qualification Utility Group (SQUG) for commercial nuclear power plants, as outlined in their Generic Implementation Procedure (GIP), would provide a substantial benefit for the seismic adequacy verification of equipment at RFP. However, further review of the simplified guidelines contained in the GIP with respect to the specific RFP structures and components revealed substantial differences from the GIP criteria. Therefore, the number of ``outliers`` from the experience database defined in the GIP is greater than was initially anticipated. This paper presents details of the differences found between the RFP structures and components and those represented in the GIP, and the challenges presented for their evaluation at RFP. Approaches necessary to develop seismic verification data are also discussed. The discussions focus on experience with one of the nuclear facilities at RFP, Building 707. However, the conclusions are generally applicable to other similar facilities that typically comprise the RFP nuclear facilities.

  15. 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.

  16. Conceptual design for the STAR barrel electromagnetic calorimeter support rings

    SciTech Connect (OSTI)

    Bielick, E.; Fornek, T.; Spinka, H.; Underwood, D.

    1994-02-15T23:59:59.000Z

    The STAR electromagnetic calorimeter (EMC) will be used to measure the energy of photons and electrons from collisions of beams of particles in the RHIC accelerator under construction at Brookhaven National Laboratory. The present design is documented in the EMC Conceptual Design Report, and consists of a cylindrical barrel and two flat endcap calorimeter sections. The barrel EMC will consist of 120 modules, each subtending 6{degrees} in azimuthal angle about the beam ({phi}), and half the barrel length. Each module will be subdivided into ``towers`` of alternating scintillator and lead, which project to the nominal interaction point. There is a strong coupling between the designs for the EMC and for the conventional solenoidal magnet, which will be located immediately outside the barrel EMC. For example, the inner radius of the magnet must be minimized to lower costs and to reduce the STAR detector`s outer diameter to fit within constraints of the existing detector building. This condition requires the calorimeter modules to be just thick enough to accomplish physics goals and to support their weight with small deflections. This note describes progress in the design of the EMC support rings. Several ring designs and methods of construction have been considered. In addition, installation and alignment problems for both the rings and the rails have been considered in more depth. Finally, revised stress calculations for the recommended ring designs have been performed. Most of this work has been done in close collaboration with the STAR magnet subgroup.

  17. Minimum Energy Consumption in Multicomponent Distillation. 1. Vmin Diagram for a Two-Product Column

    E-Print Network [OSTI]

    Skogestad, Sigurd

    of Science and Technology, N-7491 Trondheim, Norway The Vmin diagram is introduced to effectively visualize derivation of the Vmin diagram was based on computing pinch zone compositions for columns with an infinite 215 and 316 of this series. The behavior of composition profiles and pinch zones in a column and how

  18. Active Vapor Split Control for Dividing-Wall Columns Deeptanshu Dwivedi,

    E-Print Network [OSTI]

    Skogestad, Sigurd

    , Norway ABSTRACT: Dividing-wall distillation columns offer large potential energy savings over the energy requirements. INTRODUCTION Dividing-wall distillation columns such as Petlyuk arrangements, where the vapor fraction or degree of subcooling in the feed is varied to achieve optimum operation.13

  19. Use of Two Distillation Columns in Systems with Maximum Temperature Limitations

    E-Print Network [OSTI]

    Gilchrist, James F.

    Use of Two Distillation Columns in Systems with Maximum Temperature Limitations Rebecca H. Masel, Pennsylvania 18015, United States ABSTRACT: Maximum temperature limitations are encountered in distillation of the bottoms product fixes the column base pressure and, hence, the condenser pressure. The distillate

  20. Optimal Operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionating

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Optimal Operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionating Vidar Trondheim, Norway Keywords: Distillation, Petlyuk, Divided-wall, Minimum energy Abstract This paper shows the unexpected result that over-fractionating one of the product streams in a Petlyuk distillation column may

  1. Dividing wall columns for heterogeneous azeotropic distillation Quang-Khoa Le1

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Dividing wall columns for heterogeneous azeotropic distillation Quang-Khoa Le1 , Ivar J. Halvorsen2 of this work is to implement heterogeneous azeotropic distillation schemes in a dividing wall column (DWC distillation, Petlyuk arrangement, energy saving. 1. Introduction Distillation is one of the most energy

  2. Rigorous Separation Design. 1. Multicomponent Mixtures, Nonideal Mixtures, and Prefractionating Column Networks

    E-Print Network [OSTI]

    Linninger, Andreas A.

    -integrated prefractionating columns. Our employed inverse design procedure enables the systematic design of physically process design with ecological or energy targets.1,2 Distillation is arguably the most significant suggested.4­12 For example, thermally coupled distillation columns known as Petlyuk configurations13 only

  3. Identification and analysis of possible splits for azeotropic mixtures. 2. Method for simple columns

    E-Print Network [OSTI]

    Skogestad, Sigurd

    disadvantages of the conventional cut-and-try method for the design of distillation columns used in commercial columns Felix Petlyuk a , Roman Danilov b,n , Stathis Skouras c , Sigurd Skogestad d a NYC, USA b ECT 6 October 2011 Available online 14 October 2011 Keywords: Azeotrope Distillation Phase equilibrium

  4. Cyclotron waves in a non-neutral plasma column Daniel H. E. Dubin

    E-Print Network [OSTI]

    California at San Diego, University of

    plasma column with near-Maxwellian velocity distributions. We focus on the z-independent componentCyclotron waves in a non-neutral plasma column Daniel H. E. Dubin Citation: Phys. Plasmas 20. Additional information on Phys. Plasmas Journal Homepage: http://pop.aip.org/ Journal Information: http

  5. Cyclotron Waves in a Nonneutral Plasma Column Daniel H.E. Dubin

    E-Print Network [OSTI]

    California at San Diego, University of

    plasma column with near-Maxwellian velocity distributions. We focus on the z-independent componentCyclotron Waves in a Nonneutral Plasma Column Daniel H.E. Dubin Department of Physics, University of California at San Diego, La Jolla, California 92093 (Dated: February 22, 2013 [submitted to Phys. Plasmas

  6. Cyclotron waves in a non-neutral plasma column Daniel H. E. Dubin

    E-Print Network [OSTI]

    California at San Diego, University of

    plasma column with near-Maxwellian velocity distributions. We focus on the z-independent component#12;Cyclotron waves in a non-neutral plasma column Daniel H. E. Dubin Department of Physics April 2013; published online 25 April 2013) A kinetic theory of linear electrostatic plasma waves

  7. Optogalvanic isotope enrichment of Cu ions in Cu-Ne positive column discharges

    E-Print Network [OSTI]

    Kushner, Mark

    Optogalvanic isotope enrichment of Cu ions in Cu-Ne positive column discharges M. J. Kushner The isotopic enrichment of copper ions in a positive column Cu-Ne discharge using optogalvanic excitation the 63-amu isotope of copper is enriched relative to the neutral abundance. Enrichment as large as 10

  8. A dusty plasma device for producing extended, steady state, magnetized, dusty plasma columns

    E-Print Network [OSTI]

    Merlino, Robert L.

    A dusty plasma device for producing extended, steady state, magnetized, dusty plasma columns Wenjun with an existing Q machine, to produce extended, steady state, magnetized plasma columns. The dusty plasma device (DPD) is to be used for the investigation of waves in dusty plasmas and of other plasma/dust aspects

  9. The production and degradation of trichloroacetic acid in soil: results from in situ soil column experiments 

    E-Print Network [OSTI]

    Heal, Mathew R; Dickey, Catherine A; Heal, Kate V; Stidson, Ruth T; Matucha, Miroslav; Cape, J Neil

    2010-01-01T23:59:59.000Z

    experiments with radioactively-labelled TCA and with irradiated (sterilised) soil columns. Control in situ forest soil columns showed evidence of net export (i.e. in situ production) of TCA, consistent with a net soil TCA production inferred from forest...

  10. Journal of Fluids and Structures 22 (2006) 135171 Water hammer with column separation: A historical review

    E-Print Network [OSTI]

    Tijsseling, A.S.

    2006-01-01T23:59:59.000Z

    Available online 13 October 2005 Abstract Column separation refers to the breaking of liquid columns. Gaseous cavitation and steam condensation are beyond the scope of the paper. r 2005 Elsevier Ltd. All vaporous cavitation model HGL hydraulic grade line MOC method of characteristics Scalars A cross

  11. Chromate transport through columns packed with surfactant-modified zeolite/zero valent iron pellets

    E-Print Network [OSTI]

    Li, Zhaohui

    Chromate transport through columns packed with surfactant-modified zeolite/zero valent iron pellets Chromate transport through columns packed with zeolite/zero valent iron (Z/ZVI) pellets, either untreated originated from chromate sorption onto the HDTMA modified Z/ZVI pellets. Due to dual porosity, the presence

  12. Model predictive control of a pilot-scale distillation column using a programmable automation controller

    E-Print Network [OSTI]

    Model predictive control of a pilot-scale distillation column using a programmable automation). The controller is tested on a pilot-scale binary distillation column to track reference temperatures. A majorRIO) to control a pilot-scale binary distillation col- umn. Both the PI-controllers and the supervising online MPC

  13. THE POWER SUPPLY SYSTEM FOR THE ACCELERATING COLUMN OF THE 2 MEV ELECTRON COOLER FOR COSY

    E-Print Network [OSTI]

    Kozak, Victor R.

    a high-energy electron beam. The power supply for the accelerating column of the electron cooling systemTHE POWER SUPPLY SYSTEM FOR THE ACCELERATING COLUMN OF THE 2 MEV ELECTRON COOLER FOR COSY D controlled voltage source for 60 kV, 1mA and an additional supply for the solenoids of the magnetic system

  14. Using observations of deep convective systems to constrain atmospheric column absorption of solar radiation in the

    E-Print Network [OSTI]

    Dong, Xiquan

    column absorption of solar radiation (Acol) is a fundamental part of the Earth's energy cycle.e., the Acol values at both regions converge to the same value ($0.27 of the total incoming solar radiation to constrain atmospheric column absorption of solar radiation in the optically thick limit, J. Geophys. Res

  15. Behavior of Reinforced Concrete ColumnSteel Beam Roof Level T-Connections under Displacement Reversals

    E-Print Network [OSTI]

    Parra-Montesinos, Gustavo J.

    Behavior of Reinforced Concrete Column­Steel Beam Roof Level T-Connections under Displacement study on the seismic response of two hybrid RC column-to-steel S beam RCS roof level T longitudinal bars; and 2 confinement requirements in RCS roof level T-connections. In the first subassembly

  16. PRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux

    E-Print Network [OSTI]

    Mallin, Michael

    PRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux: patterns of oxygen dissolved oxygen (DO) levels often occur during summer in tidal creeks along the southeastern coast of the USA. We analyzed rates of oxygen loss as water-column biochemical oxygen demand (BOD5) and sediment

  17. Weak-Axis Behavior of Wide Flange Columns Subjected to Blast

    E-Print Network [OSTI]

    Bruneau, Michel

    the effect of blast loading on wide flange columns loaded perpendicular to the weak axis of bending field detonations. Furthermore, past studies investigating the effect of blast load- ing on wide flangeWeak-Axis Behavior of Wide Flange Columns Subjected to Blast Nagarjun Krishnappa1 ; Michel Bruneau

  18. RESEARCH NOTE: DEFLECTION EQUATION FOR THE BUCKLING OF AN ELASTIC COLUMN

    E-Print Network [OSTI]

    Newland, David E.

    13 RESEARCH NOTE: DEFLECTION EQUATION FOR THE BUCKLING OF AN ELASTIC COLUMN SUBJECTED TO SURFACE. Introduction THE EFFECT of pressure on the buckling of elastic columns has been studied for at least the last to axial load and lateral pressure. Other authors have considered the theoretical aspects (Handelman (4

  19. Micro-miniature gas chromatograph column disposed in silicon wafers

    DOE Patents [OSTI]

    Yu, Conrad M. (Antioch, CA)

    2000-01-01T23:59:59.000Z

    A micro-miniature gas chromatograph column is fabricated by forming matching halves of a circular cross-section spiral microcapillary in two silicon wafers and then bonding the two wafers together using visual or physical alignment methods. Heating wires are deposited on the outside surfaces of each wafer in a spiral or serpentine pattern large enough in area to cover the whole microcapillary area inside the joined wafers. The visual alignment method includes etching through an alignment window in one wafer and a precision-matching alignment target in the other wafer. The two wafers are then bonded together using the window and target. The physical alignment methods include etching through vertical alignment holes in both wafers and then using pins or posts through corresponding vertical alignment holes to force precision alignment during bonding. The pins or posts may be withdrawn after curing of the bond. Once the wafers are bonded together, a solid phase of very pure silicone is injected in a solution of very pure chloroform into one end of the microcapillary. The chloroform lowers the viscosity of the silicone enough that a high pressure hypodermic needle with a thumbscrew plunger can force the solution into the whole length of the spiral microcapillary. The chloroform is then evaporated out slowly to leave the silicone behind in a deposit.

  20. Cyclotron waves in a non-neutral plasma column

    SciTech Connect (OSTI)

    Dubin, Daniel H. E. [Department of Physics, University of California at San Diego, La Jolla, California 92093 (United States)

    2013-04-15T23:59:59.000Z

    A kinetic theory of linear electrostatic plasma waves with frequencies near the cyclotron frequency {Omega}{sub c{sub s}} of a given plasma species s is developed for a multispecies non-neutral plasma column with general radial density and electric field profiles. Terms in the perturbed distribution function up to O(1/{Omega}{sub c{sub s}{sup 2}}) are kept, as are the effects of finite cyclotron radius r{sub c} up to O(r{sub c}{sup 2}). At this order, the equilibrium distribution is not Maxwellian if the plasma temperature or rotation frequency is not uniform. For r{sub c}{yields}0, the theory reproduces cold-fluid theory and predicts surface cyclotron waves propagating azimuthally. For finite r{sub c}, the wave equation predicts that the surface wave couples to radially and azimuthally propagating Bernstein waves, at locations where the wave frequency equals the local upper hybrid frequency. The equation also predicts a second set of Bernstein waves that do not couple to the surface wave, and therefore have no effect on the external potential. The wave equation is solved both numerically and analytically in the WKB approximation, and analytic dispersion relations for the waves are obtained. The theory predicts that both types of Bernstein wave are damped at resonances, which are locations where the Doppler-shifted wave frequency matches the local cyclotron frequency as seen in the rotating frame.

  1. Star-planet magnetic interaction and evaporation of planetary atmospheres

    E-Print Network [OSTI]

    Lanza, A F

    2013-01-01T23:59:59.000Z

    Stars interact with their close-in planets through radiation, gravitation, and magnetic fields. We investigate the energy input to a planetary atmosphere by reconnection between stellar and planetary magnetic fields and compare it to the energy input of the extreme ultraviolet (EUV) radiation field of the star. We quantify the power released by magnetic reconnection at the boundary of the planetary magnetosphere that is conveyed to the atmosphere by accelerated electrons. We introduce simple models to evaluate the energy spectrum of the accelerated electrons and the energy dissipated in the atmospheric layers in the polar regions of the planet upon which they impinge. A simple transonic isothermal wind flow along field lines is considered to estimate the increase in mass loss rate in comparison with a planet irradiated only by the EUV flux of its host star. We find that energetic electrons can reach levels down to column densities of 10^{23}-10^{25} m^{-2}, comparable with or deeper than EUV photons, and incr...

  2. Cosmic constraint on unified model of dark sectors in flat and non-flat varying gravitational constant theory

    E-Print Network [OSTI]

    Lu, Jianbo; Wu, Yabo; Xu, Lixin

    2015-01-01T23:59:59.000Z

    Observations indicate that most universal matter are invisible and gravitational constant $G(t)$ maybe depends on the time. The theory of variation of $G$ (VG) is explored in this paper, with naturally resulting to the invisible components in universe. We utilize the observational data: lookback time data, model-independent gamma ray bursts data, growth function of matter linear perturbations, type Ia supernovae data with systematic errors, cosmic microwave background, and baryon acoustic oscillation data from the radial scale measurement and the peak-positions measurement, to restrict the unified model (UM) of dark components in VG theory. Using the best-fit values of parameters with the covariance matrix, constraints on the variation of $G$ are $(\\frac{G}{G_{0}})_{z=3.5}\\simeq 1.0003^{+0.0014}_{-0.0016}$ and $(\\frac{\\dot{G}}{G})_{today}\\simeq 0.7977^{+2.3566}_{-2.3566}\\times 10^{-13} yr^{-1}$ in a flat geometry, the small uncertainties around constants. Limit on equation of state of dark matter is $w_{0dm}=...

  3. Technical safety appraisal: Buildings 776/777 Rocky Flats Plant

    SciTech Connect (OSTI)

    Field, H C

    1988-03-01T23:59:59.000Z

    Buildings 776/777 at the Rocky Flats Plant are major components of the production complex at the plant site. They have been in operation since 1957. The operations taking place in the buildings are nuclear weapons production support, processing of weapons assemblies returned from Pantex, waste processing, research and development in support of production, special projects, and those generated by support groups, such as maintenance. The appraisal team identified nine deficiencies that it believed required prompt attention. DOE management for EH, the program office (Defense Programs), and the field office analyzed the information provided by the appraisal team and instituted compensatory measures for closer monitoring of contractor activities by knowledgeable DOE staff and staff from other sites. Concurrently, the contractor was requested to address both short-term and long-term remedial measures to correct the identified issues as well as the underlying problems. The contractor has provided his action plan, which is included. This plan was under evaluation by EH and the DOE program office at the time this report was prepared. In addressing the major areas of concern identified above, a well as the specific deficiencies identified by the appraisal team, the contractor and the field office are cautioned to search for the root causes for the problems and to direct corrective actions to those root causes rather than solely to the symptoms to assure the sustainability of the improvements being made. The results of prior TSAs led DOE to conclude that previous corrective actions were not sufficient in that a large number of the individual findings are recurrent. Pending completion of remedial actions over the next few months, enhanced DOE oversight of the contractor is warranted.

  4. ENERGY STAR Webinar: Financing Energy Efficient Upgrades with...

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

    ENERGY STAR Webinar: Financing Energy Efficient Upgrades with ENERGY STAR ENERGY STAR Webinar: Financing Energy Efficient Upgrades with ENERGY STAR October 21, 2014 2:00PM to...

  5. ENERGY STAR Webinar: Financing Energy Efficient Upgrades with ENERGY STAR

    Broader source: Energy.gov [DOE]

    Hosted by ENERGY STAR, this webinar will show how public sector organizations are improving energy efficiency with innovative solutions to financial barriers.

  6. Triggered Star Formation in the Environment of Young Massive Stars

    E-Print Network [OSTI]

    M. Gritschneder; T. Naab; F. Heitsch; A. Burkert

    2006-09-26T23:59:59.000Z

    Recent observations with the Spitzer Space Telescope show clear evidence that star formation takes place in the surrounding of young massive O-type stars, which are shaping their environment due to their powerful radiation and stellar winds. In this work we investigate the effect of ionising radiation of massive stars on the ambient interstellar medium (ISM): In particular we want to examine whether the UV-radiation of O-type stars can lead to the observed pillar-like structures and can trigger star formation. We developed a new implementation, based on a parallel Smooth Particle Hydrodynamics code (called IVINE), that allows an efficient treatment of the effect of ionising radiation from massive stars on their turbulent gaseous environment. Here we present first results at very high resolution. We show that ionising radiation can trigger the collapse of an otherwise stable molecular cloud. The arising structures resemble observed structures (e.g. the pillars of creation in the Eagle Nebula (M16) or the Horsehead Nebula B33). Including the effect of gravitation we find small regions that can be identified as formation places of individual stars. We conclude that ionising radiation from massive stars alone can trigger substantial star formation in molecular clouds.

  7. New holographic scalar field models of dark energy in non-flat universe

    E-Print Network [OSTI]

    K. Karami; J. Fehri

    2009-12-08T23:59:59.000Z

    Motivated by the work of Granda and Oliveros [L.N. Granda, A. Oliveros, Phys. Lett. B {\\bf 671}, 199 (2009)], we generalize their work to the non-flat case. We study the correspondence between the quintessence, tachyon, K-essence and dilaton scalar field models with the new holographic dark energy model in the non-flat FRW universe. We reconstruct the potentials and the dynamics for these scalar field models, which describe accelerated expansion of the universe. In the limiting case of a flat universe, i.e. $k = 0$, all results given in [L.N. Granda, A. Oliveros, Phys. Lett. B {\\bf 671}, 199 (2009)] are obtained.

  8. A Corona Australis cloud filament seen in NIR scattered light I. Comparison with extinction of background stars

    E-Print Network [OSTI]

    M. Juvela; V. -M. Pelkonen; P. Padoan; K. Mattila

    2008-01-09T23:59:59.000Z

    With current near-infrared (NIR) instruments the near-infrared light scattered from interstellar clouds can be mapped over large areas. The surface brightness carries information on the line-of-sight dust column density. Therefore, scattered light could provide an important tool to study mass distribution in quiescent interstellar clouds at a high, even sub-arcsecond resolution. We wish to confirm the assumption that light scattering dominates the surface brightness in all NIR bands. Furthermore, we want to show that scattered light can be used for an accurate estimation of dust column densities in clouds with Av in the range 1-15mag. We have obtained NIR images of a quiescent filament in the Corona Australis molecular cloud. The observations provide maps of diffuse surface brightness in J, H, and Ks bands. Using the assumption that signal is caused by scattered light we convert surface brightness data into a map of dust column density. The same observations provide colour excesses for a large number of background stars. These data are used to derive an extinction map of the cloud. The two, largely independent tracers of the cloud structure are compared. Results. In regions below Av=15m both diffuse surface brightness and background stars lead to similar column density estimates. The existing differences can be explained as a result of normal observational errors and bias in the sampling of extinctions provided by the background stars. There is no indication that thermal dust emission would have a significant contribution even in the Ks band. The results show that, below Av=15mag, scattered light does provide a reliable way to map cloud structure. Compared with the use of background stars it can also in practice provide a significantly higher spatial resolution.

  9. Nuclear Star Clusters and Bulges

    E-Print Network [OSTI]

    Cole, David R

    2015-01-01T23:59:59.000Z

    Nuclear star clusters are among the densest stellar systems known and are common in both early- and late-type galaxies. They exhibit scaling relations with their host galaxy which may be related to those of supermassive black holes. These may therefore help us to unravel the complex physical processes occurring at the centres of galaxies. The properties of nuclear stellar systems suggest that their formation requires both dissipational and dissipationless processes. They have stellar populations of different ages, from stars as old as their host galaxy to young stars formed in the last 100 Myr. Therefore star formation must be happening either directly in the nuclear star cluster or in its vicinity. The secular processes that fuel the formation of pseudobulges very likely also contributes to nuclear star cluster growth.

  10. Spontaneous Scalarization and Boson Stars

    E-Print Network [OSTI]

    A. W. Whinnett

    2000-02-17T23:59:59.000Z

    We study spontaneous scalarization in Scalar-Tensor boson stars. We find that scalarization does not occur in stars whose bosons have no self-interaction. We introduce a quartic self-interaction term into the boson Lagrangian and show that when this term is large, scalarization does occur. Strong self-interaction leads to a large value of the compactness (or sensitivity) of the boson star, a necessary condition for scalarization to occur, and we derive an analytical expression for computing the sensitivity of a boson star in Brans-Dicke theory from its mass and particle number. Next we comment on how one can use the sensitivity of a star in any Scalar-Tensor theory to determine how its mass changes when it undergoes gravitational evolution. Finally, in the Appendix, we derive the most general form of the boson wavefunction that minimises the energy of the star when the bosons carry a U(1) charge.

  11. New Abundansec From Very Old Stars

    E-Print Network [OSTI]

    Hansen, T; Christlieb, N; Yong, D; Beers, T C; Andersen, J

    2015-01-01T23:59:59.000Z

    Metal-poor stars hold the fossil record of the Galactic chemical evolution and nucleosynthesis processes that took place at the earliest times in the history of our Galaxy. From detailed abundance studies of low mass, extremely metal-poor stars ([Fe/H] capture. The sample includes some of the most metal-poor stars ([Fe/H] capture elements, and also a number of stars enhanced in carbon. The so called CEMP (carbon enhanced metal-poor) stars, these stars make up ~20% of the stars with [Fe/H] < -3, and 80% of the stars with [Fe/H] < -4.5. The progenitors of CEMP stars is still ...

  12. Flat-top pulse generation based on the combined action of active mode locking and nonlinear polarization rotation

    E-Print Network [OSTI]

    Wai, Ping-kong Alexander

    Flat-top pulse generation based on the combined action of active mode locking and nonlinear: A pulsewidth tunable 10 GHz flat-top pulse train is generated based on the combined action of active mode can be improved by using flat top clock pulses for the demultiplexing. Recently, there are reports

  13. EVIDENCE OF CONTRIBUTION OF INTERVENING CLOUDS TO GAMMA-RAY BURST'S X-RAY COLUMN DENSITY

    SciTech Connect (OSTI)

    Wang, J., E-mail: wj@bao.ac.cn [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2013-10-20T23:59:59.000Z

    The origin of excess of X-ray column density with respect to optical extinction in gamma-ray bursts (GRBs) is still a puzzle. A proposed explanation of the excess is the photoelectric absorption due to the intervening clouds along a GRB's line of sight. Here, we test this scenario by using the intervening Mg II absorption as a tracer of the neutral hydrogen column density of the intervening clouds. We identify a connection between the large X-ray column density (and large column density ratio of log (N{sub H,X}/N{sub H{sub I}})?0.5) and large neutral hydrogen column density probed by the Mg II doublet ratio (DR). In addition, GRBs with large X-ray column density (and large ratio of log (N{sub H,X}/N{sub H{sub I}})>0) tend to have multiple saturated intervening absorbers with DR < 1.2. These results therefore indicate an additional contribution from the intervening system to the observed X-ray column density in some GRBs, although the contribution from the host galaxy alone cannot be excluded based on this study.

  14. Surface abundances of ON stars

    E-Print Network [OSTI]

    Martins, F; Palacios, A; Howarth, I; Georgy, C; Walborn, N R; Bouret, J -C; Barba, R

    2015-01-01T23:59:59.000Z

    Massive stars burn hydrogen through the CNO cycle during most of their evolution. When mixing is efficient, or when mass transfer in binary systems happens, chemically processed material is observed at the surface of O and B stars. ON stars show stronger lines of nitrogen than morphologically normal counterparts. Whether this corresponds to the presence of material processed through the CNO cycle or not is not known. Our goal is to answer this question. We perform a spectroscopic analysis of a sample of ON stars with atmosphere models. We determine the fundamental parameters as well as the He, C, N, and O surface abundances. We also measure the projected rotational velocities. We compare the properties of the ON stars to those of normal O stars. We show that ON stars are usually helium-rich. Their CNO surface abundances are fully consistent with predictions of nucleosynthesis. ON stars are more chemically evolved and rotate - on average - faster than normal O stars. Evolutionary models including rotation cann...

  15. Creating a Star on Earth

    Broader source: Energy.gov [DOE]

    At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: creating a star on Earth.

  16. Excavation of the first stars

    E-Print Network [OSTI]

    Toshikazu Shigeyama; Takuji Tsujimoto; Yuzuru Yoshii

    2003-02-17T23:59:59.000Z

    The external pollution of the first stars in the Galaxy is investigated. The first stars were born in clouds composed of the pristine gas without heavy elements. These stars accreted gas polluted with heavy elements while they still remained in the cloud. As a result, it is found that they exhibit a distribution with respect to the surface metallicity. We have derived the actual form of this distribution function. This metallicity distribution function strongly suggests that the recently discovered most metal-deficient star HE0107-5240 with [Fe/H]=-5.3 was born as a metal-free star and accreted gas polluted with heavy elements. Thus the heavy elements such as Fe in HE0107-5240 must have been supplied from supernovae of later generations exploding inside the cloud in which the star had been formed. The elemental abundance pattern on the surface of stars suffering from such an external pollution should not be diverse but exhibit the average pattern of numerous supernovae. Future observations for a number of metal-deficient stars with [Fe/H]<-5 will be able to prove or disprove this external pollution scenario. Other possibilities to produce a star with this metallicity are also discussed.

  17. Home Performance with Energy Star

    Broader source: Energy.gov [DOE]

    Through the Home Performance with Energy Star program, Focus on Energy offers instant rewards for installing select recommended efficiency measures following a home energy audit. Energy consultants...

  18. Streamlining ENERGY STAR Appliance Testing

    Broader source: Energy.gov [DOE]

    To save taxpayer dollars and help lower the costs of innovative energy-efficient technologies, the Energy Department is streamlining ENERGY STAR testing for appliances.

  19. A Mosque Among the Stars

    E-Print Network [OSTI]

    Ahmad, Muhammad Aurangzeb; Khan, Ahmad

    2007-01-04T23:59:59.000Z

    A Mosque Among The Stars was the first anthology that dealt with the subject of Muslim characters and/or Islamic themes and Science Fiction....

  20. Star Formation Activity in the Long, Filamentary Infrared Dark Cloud G53.2

    E-Print Network [OSTI]

    Kim, Hyun-Jeong; Davis, Christopher J

    2015-01-01T23:59:59.000Z

    We present star formation activity in the infrared dark cloud (IRDC) G53.2, a remarkable IRDC located at Galactic coordinates $(l,b)\\sim(53^{\\circ}.2,\\,0^{\\circ}.0)$ based on the census of young stellar object (YSO) candidates. IRDC G53.2 was previously identified as several IRDCs in mid-IR images, but it is in fact a long ($\\gtrsim$45 pc) cloud, well consistent with a CO cloud at $v\\sim23$ \\kms\\ (or at $d\\sim$1.7 kpc). We present a point-source catalog of IRDC G53.2 that contains $\\sim$370 sources from our photometry of the {\\it Spitzer} MIPS 24 \\um\\ data and Galactic Legacy Infrared Mid-Plane Survey Extraordinaire Catalog. The classification of the identified sources based on their spectral index and control field analysis to remove field star contamination reveals that IRDC G53.2 is an active star-forming region with $\\sim$300 YSO candidates. We compare the YSO classification based on spectral index, mid-IR colors, and the wavelength range used, which results in consistent classification, except for flat-s...

  1. Sulfur-Bearing Molecules In Massive Star-Forming Regions: Observations Of OCS, CS, H2S and SO

    E-Print Network [OSTI]

    Li, Juan; Zhu, Qingfeng; Zhang, Jiangshui; Li, Di

    2015-01-01T23:59:59.000Z

    We studied sulfur chemistry of massive star-forming regions through single-dish submillimeter spectroscopy. OCS, O13CS, 13CS, H2S and SO transitions were observed toward a sample of massive star-forming regions with embedded UCH II or CH II regions. These sources could be divided into H II-hot core and H II-only sources based on their CH3CN emission. Our results show that the OCS line of thirteen sources is optically thick, with optical depth ranging from 5 to 16. Column densities of these molecules were computed under LTE conditions. CS column densities were also derived using its optically thin isotopologue 13CS. H2S is likely to be the most abundant gas-phase sulfuretted molecules in hot assive cores. Both the column density and abundance of sulfur-bearing molecules decrease significantly from H II-hot core to H II-only sources. Ages derived from hot core models appear to be consistent with star-formation theories, suggesting that abundance ratios of [CS]/[SO], [SO]/[OCS] and [OCS]/[CS] could be used as ch...

  2. Analytical and Experimental Assessment of Seismic Vulnerability of Beam-Column Joints without Transverse Reinforcement in Concrete Buildings

    E-Print Network [OSTI]

    Hassan, Wael M.

    2011-01-01T23:59:59.000Z

    of the upper block of the beam-column joint subassemblybeam-column joints. The third block of this research is theand corner joints. The second building block in the current

  3. Evaluation of Vitrification Processing Step for Rocky Flats Incinerator Ash

    SciTech Connect (OSTI)

    Wigent, W.L.; Luey, J.K.; Scheele, R.D.; Li, H.

    1999-04-08T23:59:59.000Z

    In 1997, Pacific Northwest National Laboratory (PNNL) staff developed a processing option for incinerator ash at the Rocky Flats Environmental Technology Sites (RFETS). This work was performed with support from Los Alamos National Laboratory (LANL) and Safe Sites of Colorado (SSOC). A description of the remediation needs for the RFETS incinerator ash is provided in a report summarizing the recommended processing option for treatment of the ash (Lucy et al. 1998). The recommended process flowsheet involves a calcination pretreatment step to remove carbonaceous material followed by a vitrification processing step for a mixture of glass tit and calcined incinerator ash. Using the calcination pretreatment step to remove carbonaceous material reduced process upsets for the vitrification step, allowed for increased waste loading in the final product, and improved the quality of the final product. Figure 1.1 illustrates the flow sheet for the recommended processing option for treatment of RFETS incinerator ash. In 1998, work at PNNL further developed the recommended flow sheet through a series of studies to better define the vitrification operating parameters and to address secondary processing issues (such as characterizing the offgas species from the calcination process). Because a prototypical rotary calciner was not available for use, studies to evaluate the offgas from the calcination process were performed using a benchtop rotary calciner and laboratory-scale equipment (Lucy et al. 1998). This report focuses on the vitrification process step after ash has been calcined. Testing with full-scale containers was performed using ash surrogates and a muffle furnace similar to that planned for use at RFETS. Small-scale testing was performed using plutonium-bearing incinerator ash to verify performance of the waste form. Ash was not obtained from RFETS because of transportation requirements to calcine the incinerator ash prior to shipment of the material. Because part of PNNL's work was to characterize the ash prior to calcination and to investigate the effect of calcination on product quality, representative material was obtained from LANL. Ash obtained from LANL was selected based on its similarity to that currently stored at RFETS. The plutonium-bearing ashes obtained from LANL are likely from a RFETS incinerator, but the exact origin was not identified.

  4. On the origin of ionising photons emitted by T Tauri stars

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2003-11-12T23:59:59.000Z

    We address the issue of the production of Lyman continuum photons by T Tauri stars, in an attempt to provide constraints on theoretical models of disc photoionisation. By treating the accretion shock as a hotspot on the stellar surface we show that Lyman continuum photons are produced at a rate approximately three orders of magnitude lower than that produced by a corresponding black body, and that a strong Lyman continuum is only emitted for high mass accretion rates. When our models are extended to include a column of material accreting on to the hotspot we find that the accretion column is extremely optically thick to Lyman continuum photons. Further, we find that radiative recombination of hydrogen atoms within the column is not an efficient means of producing photons with energies greater than 13.6eV, and find that an accretion column of any conceivable height suppresses the emission of Lyman continuum photons to a level below or comparable to that expected from the stellar photosphere. The photospheric Lyman continuum is itself much too weak to affect disc evolution significantly, and we find that the Lyman continuum emitted by an accretion shock is similarly unable to influence disc evolution significantly. This result has important consequences for models which use photoionisation as a mechanism to drive the dispersal of circumstellar discs, essentially proving that an additional source of Lyman continuum photons must exist if disc photoionisation is to be significant.

  5. Flatness-Based Control of Open-Channel Flow in an Irrigation Canal Using SCADA

    E-Print Network [OSTI]

    Boyer, Edmond

    Flatness-Based Control of Open-Channel Flow in an Irrigation Canal Using SCADA Tarek Rabbani, Simon of an algorithm for real-time irrigation operations using a supervision, control, and data acquisition (SCADA

  6. Methods of improving the surface flatness of thin glass sheets and silicon wafers

    E-Print Network [OSTI]

    Akilian, Mireille

    2008-01-01T23:59:59.000Z

    The manufacturing of high quality sheet glass has allowed for many technologies to advance to astonishing frontiers. With dimensions reaching ~ 3 x 3 m², sheet glass is pushing the envelope for producing massive size flat ...

  7. An evaluation of the thermal characteristics of a flat plate heat pipe spreader

    E-Print Network [OSTI]

    Chesser, Jason Blake

    2000-01-01T23:59:59.000Z

    An evaluation of the thermal characteristics of a flat plate heat pipe spreader was performed through an analytical, numerical, and experimental analysis. The physical system considered was comprised of a high heat flux heat source attached...

  8. SINGULAR LEVI-FLAT REAL ANALYTIC HYPERSURFACES By DANIEL BURNS and XIANGHONG GONG

    E-Print Network [OSTI]

    Gong, Xianghong

    SINGULAR LEVI-FLAT REAL ANALYTIC HYPERSURFACES By DANIEL BURNS and XIANGHONG GONG Abstract. We #12;24 DANIEL BURNS AND XIANGHONG GONG Let M be a real analytic hypersurface defined by r = 0

  9. Seismic fragility and retrofitting for a reinforced concrete flat-slab structure

    E-Print Network [OSTI]

    Bai, Jong-Wha

    2004-09-30T23:59:59.000Z

    The effectiveness of seismic retrofitting applied to enhance seismic performance was assessed for a five-story reinforced concrete (RC) flat-slab building structure in the central United States. In addition to this, an assessment of seismic...

  10. Experimental Investigations of Vortex Induced Vibration of A Flat Plate in Pitch Oscillation

    E-Print Network [OSTI]

    Yang, Yi

    2012-02-14T23:59:59.000Z

    A bluff structure placed in a flowing fluid, may be subjected to vortex-induced vibrations (VIV). For a flat plate with only rotational degree of freedom, the VIV is rotational oscillation. Based on the experimental investigation, vortex...

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

    SciTech Connect (OSTI)

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

    1983-10-15T23:59:59.000Z

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

  12. Flat Quartz-Crystal X-ray Spectrometer for Nuclear Forensics Applications

    E-Print Network [OSTI]

    Goodsell, Alison

    2012-10-19T23:59:59.000Z

    structure. The higher energy background radiation was blocked from reaching the detector using a customized collimator and shielding system. A flat quartz-crystal x-ray spectrometer system was designed specifically to fit the constraints and requirements...

  13. Comparison and evaluation of turbulence estimation schemes at Rocky Flats Plant

    SciTech Connect (OSTI)

    Bowen, B.M.; Pamp, S.E.

    1993-10-01T23:59:59.000Z

    The Rocky Flats Plant (RFP) routinely measures meteorological data to support Air Quality and Emergency Response activities. These data help to characterize the transport and dispersion of actual or potential airborne releases of radionuclides or other hazardous materials.

  14. DOE's Rocky Flats Cleanup Site Named 2006 Project of the Year...

    Office of Environmental Management (EM)

    U.S. Department of Energy (DOE) today announced that the Project Management Institute (PMI) has awarded its 2006 Project of the Year to DOE's Rocky Flats Environmental Technology...

  15. VWZ-0008- In the Matter of EG&G Rocky Flats, Inc.

    Broader source: Energy.gov [DOE]

    This decision will consider a Motion for Partial Dismissal and Limitation on Scope of Complainant's Claims filed by EG&G Rocky Flats, Inc. (EG&G) on June 13, 1997. In its motion, EG&G...

  16. How are flat demand charges based on the highest peak over the...

    Open Energy Info (EERE)

    How are flat demand charges based on the highest peak over the past 12 months designated in the database (LADWP does this) Home > Groups > Utility Rate Submitted by Marcroper on 11...

  17. Design of Flat-Plate Dehumidifiers for Humidification–Dehumidification Desalination Systems

    E-Print Network [OSTI]

    Sievers, Martin

    Flat-plate heat exchangers are examined for use as dehumidifiers in humidification–dehumidification (HDH) desalination systems. The temperature and humidity ratio differences that drive mass transfer are considerably higher ...

  18. EA-1146: Radioactive Waste Storage at Rocky Flats Environmental Technology Site, Golden, Colorado

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of the proposal to convert buildings at the U.S. Department of Energy Rocky Flats Environmental Technology Site from their former uses to interim waste...

  19. A Study of Multistage/Multifunction Column for Fine Particle Separation.

    SciTech Connect (OSTI)

    Chiang, S.

    1997-09-15T23:59:59.000Z

    A non-agitated multi-stage column was constructed and applied to wastewater treatment. Preliminary oil/water separation tests were performed. Excellent separation results verifies the multi-function feature of the multi-stage column. Hydrodynamic behavior is considered as the underlying cause for the separation performance. Therefore, a series of experiments were carried out to investigate the hydrodynamic parameters, including gas holdups and liquid circulating velocities. The experimental data will be used to create a mathematical model to simulate the multi-stage column process. The model will further shed light on the future scale-up of the MSTLFLO process.

  20. A STUDY OF MULTISTAGE/MULTIFUNCTION COLUMN FOR FINE PARTICLE SEPARATION

    SciTech Connect (OSTI)

    Dr. Shiao-Hung Chiang

    1999-10-01T23:59:59.000Z

    A non-agitated multi-stage column was constructed and applied to wastewater treatment. Preliminary oil/water separation tests were performed. Excellent separation results verifies the multi-function feature of the multi-stage column. Hydrodynamic behavior is considered as the underlying cause for the separation performance. Therefore, a series of experiments were carried out to investigate the hydrodynamic parameters, including gas holdups and liquid circulating velocities. The experimental data will be used to create a mathematical model to simulate the multi-stage column process. The model will further shed light on the future scale-up of the MSTLFLO process.

  1. Process for the production of ultrahigh purity silane with recycle from separation columns

    DOE Patents [OSTI]

    Coleman, Larry M. (Tonawanda, NY)

    1982-07-20T23:59:59.000Z

    Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

  2. An investigation of the buckling criteria of columns that have large angles of initial twist

    E-Print Network [OSTI]

    Jordan, Basil Magee, Jr

    1962-01-01T23:59:59.000Z

    of the requirements for the degree of MASTER OP SCIENCE August, 1962 Major Subject: Aeronautical Engineering AN INVESTIGATION OF THE BUCKLING CRITERIA. OF COLUMNS THAT HAVE LARGE ANGLES OF INITIAL TWIST A Thesis BASIL MAGEE JORDAN, JR. Approved ss to style... for the stepped columns were 2120 and 1750 pounds. The longer stepped oolumn buckled at 1750 pounds whereas the shorter column buckled at 2120 pounds. The theoretical buckling loads were calculated from mEI2 cr 2 L where m is a function of the length...

  3. Sub-to super-ambient temperature programmable microfabricated gas chromatography column

    DOE Patents [OSTI]

    Robinson, Alex L.; Anderson, Lawrence F.

    2004-03-16T23:59:59.000Z

    A sub- to super-ambient temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by combining a thermoelectric cooler and temperature sensing on the microfabricated column. Sub-ambient temperature programming enables the efficient separation of volatile organic compounds and super-ambient temperature programming enables the elution of less volatile analytes within a reasonable time. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  4. Influence of the gas-flow Reynolds number on a plasma column in a glass tube

    SciTech Connect (OSTI)

    Jin, Dong Jun; Uhm, Han S.; Cho, Guangsup [Department of Electronic and Biological Physics, Kwangwoon University, 20 Kwangwon-Ro, Nowon-Gu, Seoul 139-701 (Korea, Republic of)] [Department of Electronic and Biological Physics, Kwangwoon University, 20 Kwangwon-Ro, Nowon-Gu, Seoul 139-701 (Korea, Republic of)

    2013-08-15T23:59:59.000Z

    Atmospheric-plasma generation inside a glass tube is influenced by gas stream behavior as described by the Reynolds number (Rn). In experiments with He, Ne, and Ar, the plasma column length increases with an increase in the gas flow rate under laminar flow characterized by Rn < 2000. The length of the plasma column decreases as the flow rate increases in the transition region of 2000 < Rn < 4000. For a turbulent flow beyond Rn > 4000, the length of the plasma column is short in front of the electrode, eventually leading to a shutdown.

  5. Dynamic behavior of chemical exchange column in a water detritiation system for a fusion reactor

    SciTech Connect (OSTI)

    Yamanishi, T.; Iwai, Y. [Tritium Engineering Group, JAEA, Tokai, Ibaraki, 319-1195 (Japan)

    2008-07-15T23:59:59.000Z

    The dynamic behavior of a CECE column used for a demonstration reactor (DEMO) plant has been studied. In the case where the column was filled with natural water, the time required to achieve steady state was almost the same as that for the column operated under the total reflux mode. The manipulated variables were flow rate of the bottom stream for the control of the bottom tritium concentration, and flow rate of the hydrogen stream for the control of the top tritium concentration. For both the variables, the response curve was expressed by the first-order lag system, and a PID controller could be applied. (authors)

  6. Ion exchange columns for selective removal of cesium from aqueous radioactive waste using hydrous crystalline silico-titanates

    E-Print Network [OSTI]

    Ricci, David Michael

    1995-01-01T23:59:59.000Z

    conscious society. In Hanford, WA, hundreds of underground storage tanks hold tens of millions of gallons of aqueous radioactive waste. This liquid waste, which has a very high sodium content, contains trace amounts of radioactive cesium 137. Since... the material for batch ion exchange of the nuclear waste solution. More research was needed to investigate the material's effectiveness in a column operation. An ion exchange column system was developed to study column performance. The column design...

  7. Dredging as remediation for white phosphorus contamination at Eagle River Flats, Alaska

    SciTech Connect (OSTI)

    Walsh, M.R.; Collins, C.M.

    1998-08-01T23:59:59.000Z

    The Eagle River Flats impact area is a Ft. Richardson Superfund site. It is a salt marsh that is contaminated with white phosphorus (WP), and remediation of sediments in permanently ponded areas may require dredging. A remotely piloted dredging system was designed, constructed, and deployed at the Flats as part of the overall site remediation feasibility study. Experience gained over two years of engineering study and contract operation indicates that, although feasible and effective, this alternative is slow, difficult, and very expensive.

  8. Cavitation from bulk viscosity in neutron stars and quark stars

    E-Print Network [OSTI]

    Jes Madsen

    2009-09-30T23:59:59.000Z

    The bulk viscosity in quark matter is sufficiently high to reduce the effective pressure below the corresponding vapor pressure during density perturbations in neutron stars and strange stars. This leads to mechanical instability where the quark matter breaks apart into fragments comparable to cavitation scenarios discussed for ultra-relativistic heavy-ion collisions. Similar phenomena may take place in kaon-condensed stellar cores. Possible applications to compact star phenomenology include a new mechanism for damping oscillations and instabilities, triggering of phase transitions, changes in gravitational wave signatures of binary star inspiral, and astrophysical formation of strangelets. At a more fundamental level it points to the possible inadequacy of a hydrodynamical treatment of these processes in compact stars.

  9. ROTARY FILTER FINES TESTING FOR SMALL COLUMN ION EXCHANGE

    SciTech Connect (OSTI)

    Herman, D.

    2011-08-03T23:59:59.000Z

    SRNL was requested to quantify the amount of 'fines passage' through the 0.5 micron membranes currently used for the rotary microfilter (RMF). Testing was also completed to determine if there is any additional benefit to utilizing a 0.1 micron filter to reduce the amount of fines that could pass through the filter. Quantifying of the amount of fines that passed through the two sets of membranes that were tested was accomplished by analyzing the filtrate by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for titanium. Even with preparations to isolate the titanium, all samples returned results of less than the instrument's detection limit of 0.184 mg/L. Test results show that the 0.5 micron filters produced a significantly higher flux while showing a negligible difference in filtrate clarity measured by turbidity. The first targeted deployment of the RMF is with the Small Column Ion Exchange (SCIX) at the Savannah River Site (SRS). SCIX uses crystalline silicotitanate (CST) to sorb cesium to decontaminate a clarified salt solution. The passage of fine particles through the filter membranes in sufficient quantities has the potential to impact the downstream facilities. To determine the amount of fines passage, a contract was established with SpinTek Filtration to operate a 3-disk pilot scale unit with prototypic filter disk and various feeds and two different filter disk membranes. SpinTek evaluated a set of the baseline 0.5 micron filter disks as well as a set of 0.1 micron filter disks to determine the amount of fine particles that would pass the membrane and to determine the flux each set produced. The membrane on both disk sets is manufactured by the Pall Corporation (PMM 050). Each set of disks was run with three feed combinations: prototypically ground CST, CST plus monosodium titanate (MST), and CST, MST, plus Sludge Batch 6 (SB6) simulant. Throughout the testing, samples of the filtrate were collected, measured for turbidity, and sent back to SRNL for analysis to quantify the amount of fines that passed through the membrane. It should be noted that even though ground CST was tested, it will be transferred to the Defense Waste Processing Facility (DWPF) feed tank and is not expected to require filtration.

  10. AN EXPLANATION FOR THE DIFFERENT X-RAY TO OPTICAL COLUMN DENSITIES IN THE ENVIRONMENTS OF GAMMA RAY BURSTS: A PROGENITOR EMBEDDED IN A DENSE MEDIUM

    SciTech Connect (OSTI)

    Krongold, Yair [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-264, 04510 Mexico DF (Mexico); Prochaska, J. Xavier, E-mail: xavier@ucolick.org [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2013-09-10T23:59:59.000Z

    We study the {approx}> 10 ratios in the X-ray to optical column densities inferred from afterglow spectra of gamma ray bursts (GRBs) due to gas surrounding their progenitors. We present time-evolving photoionization calculations for these afterglows and explore different conditions of their environment. We find that homogenous models of the environment (constant density) predict X-ray columns similar to those found in the optical spectra, with the bulk of the opacity being produced by neutral material at large distances from the burst. This result is independent of gas density or metallicity. Only models assuming a progenitor immersed in a dense ({approx}10{sup 2-4} cm{sup -3}) cloud of gas (with radius {approx}10 pc), with a strong, declining gradient of density for the surrounding interstellar medium (ISM) are able to account for the large X-ray to optical column density ratios. However, to avoid an unphysical correlation between the size of this cloud and the size of the ionization front produced by the GRB, the models also require that the circumburst medium is already ionized prior to the burst. The inferred cloud masses are {approx}< 10{sup 6} M{sub Sun }, even if low metallicities in the medium are assumed (Z {approx} 0.1 Z{sub Sun }). These cloud properties are consistent with those found in giant molecular clouds and our results support a scenario in which the progenitors reside within intense star formation regions of galaxies. Finally, we show that modeling over large samples of GRB afterglows may offer strong constraints on the range of properties in these clouds, and the host galaxy ISM.

  11. Heat Transfer -2 A heat generating ( ) flat plate fuel element of thickness 2L is covered with flat plate steel cladding of

    E-Print Network [OSTI]

    Virginia Tech

    with flat plate steel cladding of thickness b. The heat generated is removed by a fluid at T, which adjoins on both sides On the sketch show regions where dT/dx is zero, constant and increasing. T , h x LL bb SteelSteel

  12. Physics of Neutron Star Crusts

    E-Print Network [OSTI]

    N. Chamel; P. Haensel

    2008-12-20T23:59:59.000Z

    The physics of neutron star crusts is vast, involving many different research fields, from nuclear and condensed matter physics to general relativity. This review summarizes the progress, which has been achieved over the last few years, in modeling neutron star crusts, both at the microscopic and macroscopic levels. The confrontation of these theoretical models with observations is also briefly discussed.

  13. Star formation in the multiverse

    SciTech Connect (OSTI)

    Bousso, Raphael; Leichenauer, Stefan [Center for Theoretical Physics, Department of Physics, University of California, Berkeley, California 94720-7300 (United States) and Lawrence Berkeley National Laboratory, Berkeley, California 94720-8162 (United States)

    2009-03-15T23:59:59.000Z

    We develop a simple semianalytic model of the star formation rate as a function of time. We estimate the star formation rate for a wide range of values of the cosmological constant, spatial curvature, and primordial density contrast. Our model can predict such parameters in the multiverse, if the underlying theory landscape and the cosmological measure are known.

  14. Thermal Evolution of Strange Stars

    E-Print Network [OSTI]

    Zhou Xia; Wang Lingzhi; Zhou Aizhi

    2007-09-03T23:59:59.000Z

    We investigated the thermal evolution of rotating strange stars with the deconfinement heating due to magnetic braking. We consider the stars consisting of either normal quark matter or color-flavor-locked phase. Combining deconfinement heating with magnetic field decay, we find that the thermal evolution curves are identical to pulsar data.

  15. Modeling of FRP-jacketed RC columns subject to combined axial and lateral loads

    E-Print Network [OSTI]

    Lee, Chung-Sheng

    2006-01-01T23:59:59.000Z

    LOCATIONS #6 u-bars @ 4" 3" PVC for axial load and verticalsteel Steel jacket encasing load stub 2" PVC for clevisattatch 3" PVC for axial load A B Vertical tiedown Column

  16. Strategic Planning -College -Agricultural Sciences & Natural Resources Unit Assessment Report -Four Column

    E-Print Network [OSTI]

    Zhang, Yuanlin

    Strategic Planning - College - Agricultural Sciences & Natural Resources Unit Assessment Report - Four Column Texas Tech University Priorities Means of Assessment & Criteria / Tasks Results Action & Natural Resources - 2013 Priority 1_Increase Enrollment and Promote Student Success (CASNR - Outcome 1

  17. Bond-Slip Behavior and Development of Bridge Column Longitudinal Reinforcing Bars in Enlarged Pile Shafts

    E-Print Network [OSTI]

    Murcia-Delso, Juan

    embedded 1829 mm (6 ft) in the pile shaft. The transversebridge drilled-shaft RC pile/columns,” Journal of Structuraland ductility of extended pile-shafts I: Analytical model,”

  18. Preparation of Papers in Two-Column Format for Conference Proceedings Sponsored by IEEE

    E-Print Network [OSTI]

    Masoudi, Husain M.

    you basic guidelines for preparing papers for conference proceedings. 15 I. INTRODUCTION Your goal). The space between the two columns is 4mm (0.17 in). Paragraph indentation is 3.5 mm (0.14 in). Left

  19. A Decomposition Method for Synthesizing Complex Column Configurations Using Tray-by-Tray GDP Models

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    , complex distillation columns, initialization, discrete decision. Abstract This paper describes on the Reversible Distillation Sequence Model (RDSM) is proposed embedding all possible alternative designs using applied mathematical programming tools to rigorously solve the distillation design problem

  20. Solution of systems of columns with energy exchange between recycle streams 

    E-Print Network [OSTI]

    Haas, Joe Ray

    1980-01-01T23:59:59.000Z

    Rate Profiles and Product Distribution for Example 10 122 32. Convergence Characteri. sties for Example 10 124 33. Execution Time and Number of Trials Required to Solve Examples 7 Through 10 126 34. Column Specifications, Feed Conditions...

  1. Lateral behavior of reinforced concrete columns supported on Type II shafts

    E-Print Network [OSTI]

    Liu, Yujia

    2012-01-01T23:59:59.000Z

    concrete strength reached the desired strength on the day of testingconcrete and reinforcing steel during the construction period and on the day of column-shaft assembly testing.during testing. However, the cracking of the concrete at the

  2. Wave Energy Extraction from an Oscillating Water Column in a Truncated Circular Cylinder

    E-Print Network [OSTI]

    Wang, Hao

    2013-07-19T23:59:59.000Z

    Oscillating Water Column (OWC) device is a relatively practical and convenient way that converts wave energy to a utilizable form, which is usually electricity. The OWC is kept inside a fixed truncated vertical cylinder, which is a hollow structure...

  3. Simulation of microbial transport and carbon tetrachloride biodegradation in intermittently-fed aquifer columns

    E-Print Network [OSTI]

    Simulation of microbial transport and carbon tetrachloride biodegradation in intermittently associated with carbon tetrachloride (CT) biodegradation in laboratory aquifer columns operated with a pulsed Hydrology: Groundwater transport; KEYWORDS: biodegradation, carbon tetrachloride, microbial transport

  4. Correction to ``Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon monoxide total columns

    E-Print Network [OSTI]

    Laat, Jos de

    Correction to ``Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon to ``Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon monoxide total columns, doi:10.1029/2007JD009378. [1] In the paper ``Scanning Imaging Absorption Spec- trometer

  5. Constraining the Power Spectrum Using the Column Density Distribution: a Status Report

    E-Print Network [OSTI]

    Lam Hui

    1997-12-04T23:59:59.000Z

    We review the arguments for how the slope of the column density distribution of the Lyman-alpha forest should depend on the matter power spectrum. The latest progress, presented by various groups in this conference and elsewhere, is summarized.

  6. A Column-Row-Parallel ASIC architecture for 3D wearable / portable medical ultrasonic imaging

    E-Print Network [OSTI]

    Chen, Kailiang

    2014-01-01T23:59:59.000Z

    This work presents a scalable Column-Row-Parallel ASIC architecture for 3D wearable / portable medical ultrasound. It leverages programmable electronic addressing to achieve linear scaling for both hardware interconnection ...

  7. Macroalgal-mediated transfers of water column nitrogen to intertidal sediments and salt marsh plants

    E-Print Network [OSTI]

    Boyer, Katharyn

    ), fueling remineralization, and nutrient fluxes back to the water column (Lavery and McComb, 1991; Hansen the relationship between algae and benthic/pelagic nutrient exchanges. For example, benthic microalgae

  8. 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 ...

  9. Seismic Assessment and Retrofit of Existing Multi-Column Bent Bridges

    E-Print Network [OSTI]

    Seismic Assessment and Retrofit of Existing Multi-Column Bent Bridges By Cole C. Mc ................................................................................................................................... 6 Seismic Activity in Western Washington State Approach ­ Bridge Modeling .............................................11 Seismic Excitations

  10. DEVELOPMENT AND DESIGN OF A MULTI-COLUMN EXPERIMENTAL SETUP FOR KR/XE SEPARATION

    SciTech Connect (OSTI)

    Troy G. Garn; Mitchell Greenhalgh; Tony Watson

    2014-12-01T23:59:59.000Z

    As a precursor to FY-15 Kr/Xe separation testing, design modifications to an existing experimental setup are warranted. The modifications would allow for multi-column testing to facilitate a Xe separation followed by a Kr separation using engineered form sorbents prepared using an INL patented process. A new cooling apparatus capable of achieving test temperatures to -40° C and able to house a newly designed Xe column was acquired. Modifications to the existing setup are being installed to allow for multi-column testing and gas constituent analyses using evacuated sample bombs. The new modifications will allow for independent temperature control for each column enabling a plethora of test conditions to be implemented. Sample analyses will be used to evaluate the Xe/Kr selectivity of the AgZ-PAN sorbent and determine the Kr purity of the effluent stream following Kr capture using the HZ-PAN sorbent.

  11. Ultra high pressure liquid chromatography column permeability and changes of the eluent properties

    SciTech Connect (OSTI)

    Gritti, Fabrice [University of Tennessee, Knoxville (UTK); Guiochon, Georges A [ORNL

    2008-01-01T23:59:59.000Z

    The behavior of four similar liquid chromatography columns (2.1 mm i.d. x30, 50, 100, and 150 mm, all packed with fine particles, average d{sub p} {approx} 1.7 {micro}m, of bridged ethylsiloxane/silica hybrid-C{sub 18}, named BEH-C{sub 18}) was studied in wide ranges of temperature and pressure. The pressure and the temperature dependencies of the viscosity and the density of the eluent (pure acetonitrile) along the columns were also derived, using the column permeabilities and applying the Kozeny-Carman and the heat balance equations. The heat lost through the external surface area of the chromatographic column was directly derived from the wall temperature of the stainless steel tube measured with a precision of C in still air and C in the oven compartment. The variations of the density and viscosity of pure acetonitrile as a function of the temperature and pressure was derived from empirical correlations based on precise experimental data acquired between 298 and 373 K and at pressures up to 1.5 kbar. The measurements were made with the Acquity UPLC chromatograph that can deliver a maximum flow rate of 2 mL/min and apply a maximum column inlet pressure of 1038 bar. The average Kozeny-Carman permeability constant of the columns was 144 {+-} 3.5%. The temperature hence the viscosity and the density profiles of the eluent along the column deviate significantly from linear behavior under high-pressure gradients. For a 1000 bar pressure drop, we measured {Delta}T = 25-30 K, ({Delta}{eta}/{eta}) {approx_equal} 100%, and ({Delta}{rho}/{rho}) {approx_equal} 10%. These results show that the radial temperature profiles are never fully developed within 1% for any of the columns, even under still-air conditions. This represents a practical advantage regarding the apparent column efficiency at high flow rates, since the impact of the differential analyte velocity between the column center and the column wall is not maximum. The interpretation of the peak profiles recorded in UPLC is discussed.

  12. The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power

    E-Print Network [OSTI]

    Lam Hui; Nickolay Y. Gnedin; Yu Zhang

    1997-02-19T23:59:59.000Z

    Absorption lines in the Lyman-alpha forest can be thought of as peaks in neutral hydrogen density along lines of sight. The column density distribution (the number density of absorption lines as a function of column density) is then a statistic of density peaks, which contains information about the underlying power spectrum. In particular, we show that the slope of the distribution provides a measure of power on scales smaller than those probed by studies of present-day large scale structure.

  13. 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...

  14. DUST EMISSION AND STAR FORMATION IN STEPHAN'S QUINTET

    SciTech Connect (OSTI)

    Natale, G.; Tuffs, R. J. [Max Planck Institute fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Xu, C. K.; Lu, N. [Infrared Processing and Analysis Center, California Institute of Technology 100-22, Pasadena, CA 91125 (United States); Popescu, C. C. [University of Central Lancashire, Preston, PR1 2HE (United Kingdom); Fischera, J. [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 Saint George Street, Toronto, ON, M5S 3H8 (Canada); Lisenfeld, U. [Department de Fisica Teorica y del Cosmos, Universidad de Granada, Granada (Spain); Appleton, P. [NASA Herschel Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Dopita, M. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Duc, P.-A. [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Dapnia/Service d'Astrophysique, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Gao, Y. [Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008 (China); Reach, W. [Spitzer Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Sulentic, J. [Instituto de Astrofisica de AndalucIa, CSIC, Apdo. 3004, 18080, Granada (Spain); Yun, M., E-mail: giovanni.natale@mpi-hd.mpg.d, E-mail: richard.buffs@mpi-hd.mpg.d [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)

    2010-12-10T23:59:59.000Z

    We analyze a comprehensive set of MIR/FIR observations of Stephan's Quintet (SQ), taken with the Spitzer Space Telescope. Our study reveals the presence of a luminous (L{sub IR} {approx} 4.6 x 10{sup 43} erg s{sup -1}) and extended component of infrared dust emission, not connected with the main bodies of the galaxies, but roughly coincident with the X-ray halo of the group. We fitted the inferred dust emission spectral energy distribution of this extended source and the other main infrared emission components of SQ, including the intergalactic shock, to elucidate the mechanisms powering the dust and polycyclic aromatic hydrocarbon emission, taking into account collisional heating by the plasma and heating through UV and optical photons. Combining the inferred direct and dust-processed UV emission to estimate the star formation rate (SFR) for each source we obtain a total SFR for SQ of 7.5 M{sub sun} yr{sup -1}, similar to that expected for non-interacting galaxies with stellar mass comparable to the SQ galaxies. Although star formation in SQ is mainly occurring at, or external to the periphery of the galaxies, the relation of SFR per unit physical area to gas column density for the brightest sources is similar to that seen for star formation regions in galactic disks. We also show that available sources of dust in the group halo can provide enough dust to produce up to L{sub IR} {approx} 10{sup 42} erg s{sup -1} powered by collisional heating. Though a minority of the total infrared emission (which we infer to trace distributed star-formation), this is several times higher than the X-ray luminosity of the halo, so could indicate an important cooling mechanism for the hot intergalactic medium (IGM) and account for the overall correspondence between FIR and X-ray emission. We investigate two potential modes of star formation in SQ consistent with the data, fueled either by gas from a virialized hot IGM continuously accreting onto the group, whose cooling is enhanced by grains injected from an in situ population of intermediate mass stars, or by interstellar gas stripped from the galaxies. The former mode offers a natural explanation for the observed baryon deficiency in the IGM of SQ as well as for the steep L{sub X}-T{sub X} relation of groups such as SQ with lower velocity dispersions.

  15. Efficiencies of Low-Mass Star and Star Cluster Formation

    E-Print Network [OSTI]

    Christopher D. Matzner; Christopher F. McKee

    2000-07-25T23:59:59.000Z

    Using a quantitative model for bipolar outflows driven by hydromagnetic protostellar winds, we calculate the efficiency of star formation assuming that available gas is either converted into stars or ejected in outflows. We estimate the efficiency of a single star formation event in a protostellar core, finding 25%-70% for cores with various possible degrees of flattening. The core mass function and the stellar initial mass function have similar slopes, because the efficiency is not sensitive to its parameters. We then consider the disruption of gas from a dense molecular clump in which a cluster of young stars is being born. In both cases, we present analytical formulae for the efficiencies that compare favorably against observations and, for clusters, against numerical simulations. We predict efficiencies in the range 30%-50% for the regions that form clusters of low-mass stars. In our model, star formation and gas dispersal happen concurrently. We neglect the destructive effects of massive stars: our results are therefore upper limits to the efficiency in regions more massive than about 3000 Msun.

  16. Roles of cavitation/column separation due to earthquake-induced hydraulic transients

    SciTech Connect (OSTI)

    Hwang, Y.D.

    1986-01-01T23:59:59.000Z

    The roles of cavitation/column separation due to earthquake-induced hydraulic transients in pipe flow were investigated experimentally and theoretically. It is known that when the system pressure during a hydraulic transient reaches the saturation pressure of the liquid, cavitation/column separation occurs. When the cavities collapse or when the separated liquid columns rejoin, very high pressures are produced. The experiment employed a pipe mounted between a constant-pressure tank and a piston-type excitation device. The resulting pressure variation at the piston was recorded continually. Comparison of pressure response for various test runs indicated that the peak pressures at/near resonance frequency were not affected significantly by the excitation velocity amplitude in cases of cavitation/column separation. These results were confirmed by comparison with theoretical analysis. A numerical method to simulate column separation/cavitation was developed. In order to eliminate numerical oscillation, the flux-correction method was introduced. Results obtained suggest that the cavitation/column separation due to earthquake-induced hydraulic transients is an important damage mechanism.

  17. Complete temperature profiles in ultra-high pressure liquid chromatography columns

    SciTech Connect (OSTI)

    Gritti, Fabrice [University of Tennessee, Knoxville (UTK); Guiochon, Georges A [ORNL

    2008-01-01T23:59:59.000Z

    The temperature profiles were calculated along and across seven packed columns (lengths 30, 50, 100, and 150 mm, i.d., 1 and 2.1 mm, all packed with Acquity UPLC, BEH-C{sub 18} particles, average d{sub p} {approx} 1.7 {micro}m) and their stainless steel tubes (o.d. 4.53 and 6.35 mm). These columns were kept horizontal and sheltered from forced air convection (i.e., under still air conditions), at room temperature. They were all percolated with pure acetonitrile, either under the maximum pressure drop (1034 bar) or at the maximum flow rate (2 mL/min) permitted by the chromatograph. The heat balance equation of chromatographic columns was discretized and solved numerically with minimum approximation. Both the compressibility and the thermal expansion of the eluent were taken into account. The boundary conditions were determined from the experimental measurements of the column inlet pressure and of the temperature profile along the column wall, which were made with a precision better than {+-}0.1 K. These calculation results provide the 3-D temperature profiles along and across the columns. The axial and radial temperature gradients are discussed in relationship with the experimental conditions used. The temperature map obtained permits a prediction of the chromatographic data obtained under a very high pressure gradient.

  18. Mass and Weak Field Limit of Boson Stars in Brans Dicke Gravity

    E-Print Network [OSTI]

    A. W. Whinnett

    1999-06-14T23:59:59.000Z

    We study boson stars in Brans Dicke gravity and use them to illustrate some of the properties of three different mass definitions: the Schwarzschild mass, the Keplerian mass and the Tensor mass. We analyse the weak field limit of the solutions and show that only the Tensor mass leads to a physically reasonable definition of the binding energy. We examine numerically strong field $\\omega=-1$ solutions and show how, in this extreme case, the three mass values and the conserved particle number behave as a function of the central boson field amplitude. The numerical studies imply that for $\\omega=-1$, solutions with extremal Tensor mass also have extremal particle number. This is a property that a physically reasonable definition of the mass of a boson star must have, and we prove analytically that this is true for all values of $\\omega$. The analysis supports the conjecture that the Tensor mass uniquely describes the total energy of an asymptotically flat solution in BD gravity.

  19. EPA ENERGY STAR: Tackling Growth in Home Electronics and Small Appliances

    E-Print Network [OSTI]

    Sanchez, Marla Christine

    2008-01-01T23:59:59.000Z

    behavior: the case of ENERGY STAR computers Unlike ENERGY STAR ME, participation in ENERGY STAR home

  20. EPA ENERGY STAR Webcast: Value of ENERGY STAR Certification

    Office of Energy Efficiency and Renewable Energy (EERE)

    For thousands of organizations, ENERGY STAR is the simple choice for saving money and demonstrating environmental leadership to the public. Lower energy costs aren't the only financial benefit of...

  1. EPA ENERGY STAR Webinar: ENERGY STAR Portfolio Manager 201

    Office of Energy Efficiency and Renewable Energy (EERE)

    Continue to learn about EPA’s ENERGY STAR Portfolio Manager tool, with a deeper dive into more advanced functionalities such as: managing and tracking changes to your property uses over time; using...

  2. ENERGY STAR Webinar: Financing Energy Efficient Upgrades with ENERGY STAR

    Broader source: Energy.gov [DOE]

    ENERGY STAR is hosting a webinar on how public sector organizations are improving energy efficiency with innovative solutions to financial barriers on Oct. 21, 2014, from 2:00 p.m. - 3:15 p.m.

  3. Star Trek Songbook Issue 3

    E-Print Network [OSTI]

    Multiple Contributors

    1976-01-01T23:59:59.000Z

    lunar flower Is growing, Somewhere beyond the stars... Beyond Antares. There waits my love, a-sleeplng, Where my heart is, where my heart is, Where the great blue crane Its watch is keeping, Somewhere beyond the stars... Beyond Antares. I...'ll be back, though It takes forever. Forever is just a day. Forever is just another journey, Tomorrow a stop along the way. Then let the years go fading, Where my heart is, where my heart Is, For my love eternally Is waiting Somewhere, beyond the stars...

  4. Relativistic outflow from two thermonuclear shell flashes on neutron stars

    E-Print Network [OSTI]

    Zand, Jean in 't; Cavecchi, Yuri

    2014-01-01T23:59:59.000Z

    We study the exceptionally short (32-41 ms) precursors of two intermediate-duration thermonuclear X-ray bursts observed with RXTE from the neutron stars in 4U 0614+09 and 2S 0918-549. They exhibit photon fluxes that surpass those at the Eddington limit later in the burst by factors of 2.6 to 3.1. We are able to explain both the short duration and the super-Eddington flux by mildly relativistic outflow velocities of 0.1$c$ to 0.3$c$ subsequent to the thermonuclear shell flashes on the neutron stars. These are the highest velocities ever measured from any thermonuclear flash. The precursor rise times are also exceptionally short: about 1 ms. This is inconsistent with predictions for nuclear flames spreading laterally as deflagrations and suggests detonations instead. This is the first time that a detonation is suggested for such a shallow ignition column depth ($y_{\\rm ign}$ = 10$^{10}$ g cm$^{-2}$). The detonation would possibly require a faster nuclear reaction chain, such as bypassing the alpha-capture on $^...

  5. Stringy Stability of Charged Dilaton Black Holes with Flat Event Horizon

    E-Print Network [OSTI]

    Yen Chin Ong; Pisin Chen

    2014-12-29T23:59:59.000Z

    Electrically charged black holes with flat event horizon in anti-de Sitter space have received much attention due to various applications in Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence, from modeling the behavior of quark-gluon plasma to superconductor. Crucial to the physics on the dual field theory is the fact that when embedded in string theory, black holes in the bulk may become vulnerable to instability caused by brane pair-production. Since dilaton arises naturally in the context of string theory, we study the effect of coupling dilaton to Maxwell field on the stability of flat charged AdS black holes. In particular, we study the stability of Gao-Zhang black holes, which are locally asymptotically anti-de Sitter. We find that for dilaton coupling parameter $\\alpha$ > 1, flat black holes are stable against brane pair production, however for 0 electrical charges is increased. Such instability however, behaves somewhat differently from that of flat Reissner-Nordstr\\"om black holes. In addition, we prove that the Seiberg-Witten action of charged dilaton AdS black hole of Gao-Zhang type with flat event horizon (at least in 5-dimension) is always logarithmically divergent at infinity for finite values of $\\alpha$, and is finite and positive in the case $\\alpha$ tends to infinity . We also comment on the robustness of our result for other charged dilaton black holes that are not of Gao-Zhang type.

  6. Hanford/Rocky Flats collaboration on development of supercritical carbon dioxide extraction to treat mixed waste

    SciTech Connect (OSTI)

    Hendrickson, D.W.; Biyani, R.K. [Westinghouse Hanford Co., Richland, WA (United States); Brown, C.M.; Teter, W.L. [Kaiser-Hill Co., Golden, CO (United States)

    1995-11-01T23:59:59.000Z

    Proposals for demonstration work under the Department of Energy`s Mixed Waste Focus Area, during the 1996 through 1997 fiscal years included two applications of supercritical carbon dioxide to mixed waste pretreatment. These proposals included task RF15MW58 of Rocky Flats and task RL46MW59 of Hanford. Analysis of compatibilities in wastes and work scopes yielded an expectation of substantial collaboration between sites whereby Hanford waste streams may undergo demonstration testing at Rocky Flats, thereby eliminating the need for test facilities at Hanford. This form of collaboration is premised the continued deployment at Rocky Flats and the capability for Hanford samples to be treated at Rocky Flats. The recent creation of a thermal treatment contract for a facility near Hanford may alleviate the need to conduct organic extraction upon Rocky Flats wastes by providing a cost effective thermal treatment alternative, however, some waste streams at Hanford will continue to require organic extraction. Final site waste stream treatment locations are not within the scope of this document.

  7. Gravitational Waves from Relativistic Stars

    E-Print Network [OSTI]

    Yasufumi Kojima

    2000-02-23T23:59:59.000Z

    Stellar pulsations in rotating relativistic stars are reviewed. Slow rotation approximation is applied to solving the Einstein equations. The rotational effects on the non-axisymmetric oscillations are explicitly shown in the polar and axial modes.

  8. Inversion of the star transform

    E-Print Network [OSTI]

    Fan Zhao; John C. Schotland; Vadim A. Markel

    2014-05-06T23:59:59.000Z

    We define the star transform as a generalization of the broken ray transform introduced by us in previous work. The advantages of using the star transform include the possibility to reconstruct the absorption and the scattering coefficients of the medium separately and simultaneously (from the same data) and the possibility to utilize scattered radiation which, in the case of the conventional X-ray tomography, is discarded. In this paper, we derive the star transform from physical principles, discuss its mathematical properties and analyze numerical stability of inversion. In particular, it is shown that stable inversion of the star transform can be obtained only for configurations involving odd number of rays. Several computationally-efficient inversion algorithms are derived and tested numerically.

  9. ENERGY STAR Portfolio Manager 101

    Office of Energy Efficiency and Renewable Energy (EERE)

    Join us as we introduce and demonstrate the core functionality of EPA’s ENERGY STAR Portfolio Manager tool. Attendees will learn how to: navigate Portfolio Manager; add a property and enter details...

  10. The STAR Vertex Position Detector

    E-Print Network [OSTI]

    W. J. Llope; J. Zhou; T. Nussbaum; G. W. Hoffmann; K. Asselta; J. D. Brandenburg; J. Butterworth; T. Camarda; W. Christie; H. J. Crawford; X. Dong; J. Engelage; G. Eppley; F. Geurts; J. Hammond; E. Judd; D. L. McDonald; C. Perkins; L. Ruan; J. Scheblein; J. J. Schambach; R. Soja; K. Xin; C. Yang

    2014-03-26T23:59:59.000Z

    The 2x3 channel pseudo Vertex Position Detector (pVPD) in the STAR experiment at RHIC has been upgraded to a 2x19 channel detector in the same acceptance, called the Vertex Position Detector (VPD). This detector is fully integrated into the STAR trigger system and provides the primary input to the minimum-bias trigger in Au+Au collisions. The information from the detector is used both in the STAR Level-0 trigger and offline to measure the location of the primary collision vertex along the beam pipe and the event "start time" needed by other fast-timing detectors in STAR. The offline timing resolution of single detector channels in full-energy Au+Au collisions is ~100 ps, resulting in a start time resolution of a few tens of picoseconds and a resolution on the primary vertex location of ~1 cm.

  11. ENERGY STAR Portfolio Manager 201

    Office of Energy Efficiency and Renewable Energy (EERE)

    Continue to learn about EPA’s new ENERGY STAR Portfolio Manager tool, with a deeper dive into more advanced functionalities such as: managing and tracking changes to your property uses over time;...

  12. NYSERDA- Energy Star Home Builders

    Broader source: Energy.gov [DOE]

    NYSERDA offers a program to encourage more industry involvement in the building of Energy Star rated Homes. Incentives are available for newly constructed residential dwellings of 3 stories or less...

  13. The low frequency 2D vibration sensor based on flat coil element

    SciTech Connect (OSTI)

    Djamal, Mitra; Sanjaya, Edi; Islahudin; Ramli [Department of Physics, Institut Teknologi Bandung, Jl. Ganesa 10 Bandung 40116 (Indonesia); Department of Physics, Institut Teknologi Bandung, Jl. Ganesa 10 Bandung 40116 (Indonesia) and Department of Physics, UIN Syarif Hidayatullah, Jl. Ir.H. Djuanda 95 Ciputat 15412 (Indonesia); MTs NW Nurul Iman Kembang Kerang, Jl. Raya Mataram - Lb.Lombok, NTB (Indonesia); Department of Physics, Institut Teknologi Bandung, Jl. Ganesa 10 Bandung 40116 (Indonesia) and Department of Physics,Universitas Negeri Padang, Jl. Prof. Hamka, Padang 25132 (Indonesia)

    2012-06-20T23:59:59.000Z

    Vibration like an earthquake is a phenomenon of physics. The characteristics of these vibrations can be used as an early warning system so as to reduce the loss or damage caused by earthquakes. In this paper, we introduced a new type of low frequency 2D vibration sensor based on flat coil element that we have developed. Its working principle is based on position change of a seismic mass that put in front of a flat coil element. The flat coil is a part of a LC oscillator; therefore, the change of seismic mass position will change its resonance frequency. The results of measurements of low frequency vibration sensor in the direction of the x axis and y axis gives the frequency range between 0.2 to 1.0 Hz.

  14. Dynamical generation of Floquet Majorana flat bands in s-wave superconductors

    E-Print Network [OSTI]

    Amrit Poudel; Gerardo Ortiz; Lorenza Viola

    2014-12-08T23:59:59.000Z

    We present quantum control techniques to engineer flat bands of symmetry-protected Majorana edge modes in s-wave superconductors. Specifically, we show how periodic control may be employed for designing time-independent effective Hamiltonians, which support $Floquet$ $Majorana$ $flat$ $bands$, starting from equilibrium conditions that are either topologically trivial or only support individual Majorana pairs. In the first approach, a suitable modulation of the chemical potential simultaneously induces Majorana flat bands and dynamically $activates$ a pre-existing chiral symmetry which is responsible for their protection. In the second approach, the application of effective parity kicks dynamically $generates$ a desired chiral symmetry by suppressing chirality-breaking terms in the static Hamiltonian. Our results demonstrate how the use of time-dependent control enlarges the range of possibilities for realizing gapless topological superconductivity, potentially enabling access to topological states of matter that have no known equilibrium counterpart.

  15. STAR Vertex Detector Upgrade Development

    SciTech Connect (OSTI)

    Greiner, Leo C.; Matis, Howard S.; Stezelberger, Thorsten; Vu,Chinh Q.; Wieman, Howard; Szelezniak, Michal; Sun, Xiangming

    2008-01-28T23:59:59.000Z

    We report on the development and prototyping efforts undertaken with the goal of producing a micro-vertex detector for the STAR experiment at the RHIC accelerator at BNL. We present the basic detector requirements and show a sensor development path, conceptual mechanical design candidates and readout architecture. Prototyping and beam test results with current generation MimoSTAR-2 sensors and a readout system featuring FPGA based on-the-fly hit finding and data sparsification are also presented.

  16. Measurement of changes in linear accelerator photon energy through flatness variation using an ion chamber array

    SciTech Connect (OSTI)

    Gao Song; Balter, Peter A. [Department of Radiation Physics, Unit 94, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Rose, Mark; Simon, William E. [Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States)

    2013-04-15T23:59:59.000Z

    Purpose: To compare the use of flatness versus percent depth dose (PDD) for determining changes in photon beam energy for a megavoltage linear accelerator. Methods: Energy changes were accomplished by adjusting the bending magnet current by up to {+-}15% in 5% increments away from the value used clinically. Two metrics for flatness, relative flatness in the central 80% of the field (Flat) and average maximum dose along the diagonals normalized by central axis dose (F{sub DN}), were measured using a commercially available planner ionization chamber array. PDD was measured in water at depths of 5 and 10 cm in 3 Multiplication-Sign 3 cm{sup 2} and 10 Multiplication-Sign 10 cm{sup 2} fields using a cylindrical chamber. Results: PDD was more sensitive to changes in energy when the beam energy was increased than when it was decreased. For the 18-MV beam in particular, PDD was not sensitive to energy reductions below the nominal energy. The value of Flat was found to be more sensitive to decreases in energy than to increases, with little sensitivity to energy increases above the nominal energy for 18-MV beams. F{sub DN} was the only metric that was found to be sensitive to both increases and reductions of energy for both the 6- and 18-MV beams. Conclusions: Flatness based metrics were found to be more sensitive to energy changes than PDD, In particular, F{sub DN} was found to be the most sensitive metric to energy changes for photon beams of 6 and 18 MV. The ionization chamber array allows this metric to be conveniently measured as part of routine accelerator quality assurance.

  17. Helium in Chemically Peculiar Stars

    E-Print Network [OSTI]

    F. Leone

    1998-05-05T23:59:59.000Z

    For the purpose of deriving the helium abundances in chemically peculiar stars, the importance of assuming a correct helium abundance has been investigated for determining the effective temperature and gravity of main sequence B-type stars, making full use of the present capability of reproducing their helium lines. Even if the flux distribution of main sequence B-type stars appears to depend only on the effective temperature for any helium abundance, the effective temperature, gravity and helium abundance have to be determined simultaneously by matching the Balmer line profiles. New MULTI NLTE calculations, performed adopting ATLAS9 model atmospheres and updated helium atomic parameters, reproduce most of the observed equivalent widths of neutral helium lines for main sequence B-type stars and they make us confident of the possibility to correctly derive the helium abundance in chemically peculiar stars. An application of previous methods to the helium rich star HD 37017 shows that helium could be stratified in the magnetic pole regions, as expected in the framework of the diffusion theory in the presence of mass loss.

  18. Friction factor data for flat plate tests of smooth and honeycomb surfaces

    E-Print Network [OSTI]

    Ha, Tae Woong

    1989-01-01T23:59:59.000Z

    are needed. The purpose of this report is to present the air flow friction factor data for honeycomb surfaces (i.e., 1.57 mm, 0.79 mm and 0.51 mm in cell width, 3.81 mm and 2.29 mm in cell depth) with a flat plate tester. The flat plate tester is designed....2bar, and 17.9bar, respectively and 3 clearances between honeycombs which are 0.25mm, 0.38mm and 0.51mm. These clearance values are representative of actual seals used in the turbomachinary. The following questions wil l be answered: 1) Does...

  19. THz-radiation production using dispersively-selected flat electron bunches

    E-Print Network [OSTI]

    Thangaraj, Jayakar

    2013-01-01T23:59:59.000Z

    We propose an alternative scheme for a tunable THz radiation source generated by relativistic electron bunches. This technique relies on the combination of dispersive selection and flat electron bunch. The dispersive selection uses a slit mask inside a bunch compressor to transform the energy-chirped electron beam into a bunch train. The flat beam transformation boosts the frequency range of the THz source by reducing the beam emittance in one plane. This technique generates narrow-band THz radiation with a tuning range between 0.2 - 4 THz. Single frequency THz spectrum can also be generated by properly choosing the slit spacing, slit width, and the energy chirp.

  20. Undergraduate Honors Research Projects Assessing Flat Field Quality at the University of Maryland Observatory, David Blankenship,

    E-Print Network [OSTI]

    Gruner, Daniel S.

    , Brett M. Morris, (Derek Richardson) 2012. Neutron Star Radii: Theoretical Tests of Frequency Scattering using HNBody, James Keane, (Douglas P. Hamilton) 2011 Measurements of the Mass and Radius of the Neutron Star 4U 1636-53 Using Millisecond Brightness Oscillations during Thermonuclear X-ray Bursts, Ryan

  1. Experimental study on hydrodynamic forces acting on an oscillating column with circular footing

    SciTech Connect (OSTI)

    Hoshino, Kunihiro; Sato, Hiroshi [Ministry of Transport, Mitaka (Japan). Ship Research Inst.

    1994-12-31T23:59:59.000Z

    This paper presents the results of an experimental investigation of the in-line and lift forces acting on an oscillating column with circular footing. Forced surging tests were carried out using a column with circular footing of which ratio of diameter was varied from 1.25 to 2.5. The in-line and lift force have been measured concerning both the whole model and the parts of column and footing. The drag coefficients, inertia coefficients, coefficients of root-mean-square values of the in-line force and lift force coefficients in the range of Keulegan Carpenter number from 5 to 30 have been obtained. Those results have been compared with that of a straight finite length circular cylinder.

  2. First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon

    E-Print Network [OSTI]

    Back, Henning O; Alton, Andrew; Condon, Christopher; de Haas, Ernst; Galbiati, Cristiano; Goretti, Augusto; Hohmann, Tristan; Ianni, Andrea; Kendziora, Cary; Loer, Ben; Montanari, David; Mosteiro, Pablo; Pordes, Stephen

    2012-01-01T23:59:59.000Z

    We report on the performance and commissioning of a cryogenic distillation column for low radioactivity underground argon at Fermi National Accelerator Laboratory. The distillation column is designed to accept a mixture of argon, helium, and nitrogen and return pure argon with a nitrogen contamination less than 10 ppm. In the first commissioning, we were able to run the distillation column in a continuous mode and produce argon that is 99.9% pure. After running in a batch mode, the argon purity was increased to 99.95%, with 500 ppm of nitrogen remaining. The efficiency of collecting the argon from the gas mixture was between 70% and 81%, at an argon production rate of 0.84-0.98 kg/day.

  3. First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon

    E-Print Network [OSTI]

    H. O. Back; T. Alexander; A. Alton; C. Condon; E. de Haas; C. Galbiati; A. Goretti; T. Hohmann; An. Ianni; C. Kendziora; B. Loer; D. Montanari; P. Mosteiro; S. Pordes

    2012-05-01T23:59:59.000Z

    We report on the performance and commissioning of a cryogenic distillation column for low radioactivity underground argon at Fermi National Accelerator Laboratory. The distillation column is designed to accept a mixture of argon, helium, and nitrogen and return pure argon with a nitrogen contamination less than 10 ppm. In the first commissioning, we were able to run the distillation column in a continuous mode and produce argon that is 99.9% pure. After running in a batch mode, the argon purity was increased to 99.95%, with 500 ppm of nitrogen remaining. The efficiency of collecting the argon from the gas mixture was between 70% and 81%, at an argon production rate of 0.84-0.98 kg/day.

  4. Feedback from Protostellar Outflows in Star and Star Cluster Formation

    E-Print Network [OSTI]

    Christopher D. Matzner

    2000-07-13T23:59:59.000Z

    Magnetic stresses collimate protostellar winds into a common distribution of force with angle. Sweeping into the ambient medium, such winds drive bipolar molecular outflows whose properties are insensitive to the distribution of ambient gas and to the details of how the wind is launched, and how its intensity varies over time. Moreover, these properties are in accord with the commonly observed features of outflows. This model is simple enough to permit a quantitative study of the feedback effects from low-mass star formation. It predicts the rate at which star-forming gas is ejected by winds, and hence the efficiency with which stars form. Applied to individual star formation, it relates the stellar initial mass function to the distribution of pre-stellar cores. Applied to cluster formation, it indicates whether the resulting stellar system will remain gravitationally bound. Using the energy injection and mass ejection implied by this model, we investigate the dynamical evolution of a molecular clump as a stellar cluster forms within it. This depends critically on the rate at which turbulence decays: it may involve equilibrium star formation (slow decay), overstable oscillations, or collapse (fast decay).

  5. ENERGY STAR Test Procedures and Verification | Department of...

    Energy Savers [EERE]

    ENERGY STAR ENERGY STAR Test Procedures and Verification ENERGY STAR Test Procedures and Verification The Department of Energy (DOE) is the lead agency in the development and...

  6. Oil production from thin oil columns subject to water and gas coning 

    E-Print Network [OSTI]

    Chai, Kwok Kit

    1981-01-01T23:59:59.000Z

    OIL PRODUCTION FROM THIN OIL COLUMNS SUBJECT TO MATER AND GAS CONING A Thesis by KMOK KIT CHAI Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1981... Major Subject: Petroleum Engineering OIL PRODUCTION FROM THIN OIL COLUMNS SUBJECT TO WATER AND GAS CONING A Thesis by KWOK KIT CHAI Approved as to style and content by airman of o t ee Member Member Head o Department May 1981 ABSTRACT Oil...

  7. Oil production from thin oil columns subject to water and gas coning

    E-Print Network [OSTI]

    Chai, Kwok Kit

    1981-01-01T23:59:59.000Z

    OIL PRODUCTION FROM THIN OIL COLUMNS SUBJECT TO MATER AND GAS CONING A Thesis by KMOK KIT CHAI Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1981... Major Subject: Petroleum Engineering OIL PRODUCTION FROM THIN OIL COLUMNS SUBJECT TO WATER AND GAS CONING A Thesis by KWOK KIT CHAI Approved as to style and content by airman of o t ee Member Member Head o Department May 1981 ABSTRACT Oil...

  8. Kevin E. Trenberth John Fasullo Lesley Smith Trends and variability in column-integrated atmospheric water vapor

    E-Print Network [OSTI]

    Fasullo, John

    Kevin E. Trenberth Ã? John Fasullo Ã? Lesley Smith Trends and variability in column. E. Trenberth (&) Ã? J. Fasullo Ã? L. Smith National C

  9. Supervised Learning via Discriminative k q-Flats Arthur Szlam and Guillermo Sapiro

    E-Print Network [OSTI]

    Soatto, Stefano

    modify this energy so that it penalizes classification errors. In this note we consider the following-q-flats algorithm for pattern classification is introduced in this work. The ba- sic idea is to replace the original, showing that the method is computa- tionally very efficient and gives excellent results on standard

  10. Interacting new agegraphic Phantom model of dark energy in non-flat universe

    E-Print Network [OSTI]

    M. R. Setare

    2009-07-28T23:59:59.000Z

    In this paper we consider the new agegraphic model of interacting dark energy in non-flat universe. We show that the interacting agegraphic dark energy can be described by a phantom scalar field. Then we show this phantomic description of the agegraphic dark energy and reconstruct the potential of the phantom scalar field.

  11. A SOLAR STILL AUGMENTED WITH A FLAT-PLATE COLLECTOR AND A REFLECTOR

    E-Print Network [OSTI]

    A SOLAR STILL AUGMENTED WITH A FLAT-PLATE COLLECTOR AND A REFLECTOR A. Saleh A. Badran Mechanical ­ Jordan Amman ­ Jordan e-mail: asaleh@philadelphia.edu.jo e-mail: badran@ju.edu.jo ABSTRACT A solar distillation system was built and tested to study the effect of increasing the solar radiation incident

  12. A Soft Wearable Robotic Device for Active Knee Motions using Flat Pneumatic Artificial Muscles

    E-Print Network [OSTI]

    Park, Yong-Lae

    elastomer muscles were employed for assisted knee extension and flexion. The robotic device was testedA Soft Wearable Robotic Device for Active Knee Motions using Flat Pneumatic Artificial Muscles Yong present the design of a soft wearable robotic device composed of elastomeric artificial muscle actuators

  13. Mercury Contamination from Hydraulic Placer-Gold Mining in the Dutch Flat Mining

    E-Print Network [OSTI]

    179 Mercury Contamination from Hydraulic Placer-Gold Mining in the Dutch Flat Mining District at historic gold mining sites represents a potential risk to human health and the environment. Elemental mercury (quicksilver) was used extensively for the recovery of gold at both placer and hardrock mines

  14. Dynamic pressure response of water flow between closely spaced roughened flat plates

    E-Print Network [OSTI]

    Hess, John Charles

    1993-01-01T23:59:59.000Z

    A flat plate tester was designed and built to determine friction factors and dynamic pressures for water flow over smooth, knurl, and cavity plates. Reynolds numbers between 2000 and 35000 were obtained at plate clearances of 0.076 mm to 1.270 mm...

  15. Thermal response of a flat heat pipe sandwich structure to a localized heat flux

    E-Print Network [OSTI]

    Wadley, Haydn

    The temperature distribution across a flat heat pipe sandwich structure, subjected to an intense localized thermal metal foam wick and distilled water as the working fluid. Heat was applied via a propane torch and radiative heat transfer. A novel method was developed to estimate experimentally, the heat flux distribution

  16. Tools for Closure Project and Contract Management: Development of the Rocky Flats Integrated Closure Project Baseline

    SciTech Connect (OSTI)

    Gelles, C. M.; Sheppard, F. R.

    2002-02-26T23:59:59.000Z

    This paper details the development of the Rocky Flats Integrated Closure Project Baseline - an innovative project management effort undertaken to ensure proactive management of the Rocky Flats Closure Contract in support of the Department's goal for achieving the safe closure of the Rocky Flats Environmental Technology Site (RFETS) in December 2006. The accelerated closure of RFETS is one of the most prominent projects within the Department of Energy (DOE) Environmental Management program. As the first major former weapons plant to be remediated and closed, it is a first-of-kind effort requiring the resolution of multiple complex technical and institutional challenges. Most significantly, the closure of RFETS is dependent upon the shipment of all special nuclear material and wastes to other DOE sites. The Department is actively working to strengthen project management across programs, and there is increasing external interest in this progress. The development of the Rocky Flats Integrated Closure Project Baseline represents a groundbreaking and cooperative effort to formalize the management of such a complex project across multiple sites and organizations. It is original in both scope and process, however it provides a useful precedent for the other ongoing project management efforts within the Environmental Management program.

  17. American Institute of Aeronautics and Astronautics Jet in Supersonic Crossflow on a Flat Plate

    E-Print Network [OSTI]

    Texas at Arlington, University of

    American Institute of Aeronautics and Astronautics 1 Jet in Supersonic Crossflow on a Flat Plate jet and a supersonic crossflow. A new flow model for jets in supersonic crossflow is presented present in a jet in supersonic cross-flow. Their flow structure model is shown in Fig. 1. Figure 1

  18. RIGID FLAT WEBS ON THE PROJECTIVE PLANE DAVID MARIN AND JORGE VITORIO PEREIRA

    E-Print Network [OSTI]

    Pereira, Jorge Vitório

    RIGID FLAT WEBS ON THE PROJECTIVE PLANE DAVID MAR´IN AND JORGE VIT´ORIO PEREIRA Abstract. This paper studies global webs on the projective plane with van- ishing curvature. The study is based show that the Legendre transform of what we call reduced convex foliations are webs with zero cur

  19. KINEMATIC CONTROL OF A NONHOLONOMIC WHEELED MOBILE MANIPULATOR A DIFFERENTIAL FLATNESS APPROACH

    E-Print Network [OSTI]

    Krovi, Venkat

    the terminal conditions in the flat output space while control design reduces to a pole-placement problem) electro-mechanical testing. NOMENCLATURE WMR Wheeled Mobile Robot WMM Wheeled Mobile Manipulator ( ),x y Cartesian coordinates of the center of the wheel axle of the WMR Orientation of the WMR with respect

  20. FLATNESS BASED CONTROL OF A BUCK-CONVERTER DRIVEN DC MOTOR

    E-Print Network [OSTI]

    Knobloch,Jürgen

    FLATNESS BASED CONTROL OF A BUCK-CONVERTER DRIVEN DC MOTOR Felix Antritter ,1 Peter Maurer Johann on the circuit and control design of a buck converter driven DC motor. The steps of design, as for example objective: tracking control of the DC motor's shaft angular velocity. The dynamic system composed from

  1. EIS-0064: Rocky Flats Plant Site, Jefferson County, Golden, Colorado (see also ERDA-1545-D)

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this statement to evaluate the site specific environmental impacts of continuing to conduct nuclear weapons production activities at the Rocky Flats Plant; alternatives for the conduct of such activities; and environmental impacts of the U.S. policy to produce nuclear weapons.

  2. university-logo Two papers which changed my life: Milnor's seminal work on flat manifolds

    E-Print Network [OSTI]

    Goldman, William

    university-logo Two papers which changed my life: Milnor's seminal work on flat manifolds Two Banff International Research Station February 24, 2011 #12;university-logo Two papers which changed my of Euclidean 3-space by free groups of affine transformations. #12;university-logo Two papers which changed my

  3. Heavily Obscured AGN in Star-Forming Galaxies at z~2

    E-Print Network [OSTI]

    Treister, E; Schawinski, K; Urry, C M; Gawiser, E; Virani, S; Lira, P; Kartaltepe, J; Damen, M; Taylor, E N; Le Floc'h, E; Justham, Stephen; Koekemoer, A

    2009-01-01T23:59:59.000Z

    We study the properties of a sample of 211 heavily-obscured Active Galactic Nucleus (AGN) candidates in the Extended Chandra Deep Field-South selecting objects with f_24/f_R>1000 and R-K>4.5. Of these, 18 were detected in X-rays and found to be obscured AGN with neutral hydrogen column densities of ~10^23 cm^-2. In the X-ray undetected sample, the following evidence suggests a large fraction of heavily-obscured (Compton Thick) AGN: (i) The stacked X-ray signal of the sample is strong, with an observed ratio of soft to hard X-ray counts consistent with a population of ~90% heavily obscured AGN combined with 10% star-forming galaxies. (ii) The X-ray to mid-IR ratios for these sources are significantly larger than that of star-forming galaxies and ~2 orders of magnitude smaller than for the general AGN population, suggesting column densities of N_H>5x10^24 cm^-2. (iii) The Spitzer near- and mid-IR colors of these sources are consistent with those of the X-ray-detected sample if the effects of dust self-absorptio...

  4. Old and new neutron stars

    SciTech Connect (OSTI)

    Ruderman, M.

    1984-09-01T23:59:59.000Z

    The youngest known radiopulsar in the rapidly spinning magnetized neutron star which powers the Crab Nebula, the remnant of the historical supernova explosion of 1054 AD. Similar neutron stars are probably born at least every few hundred years, but are less frequent than Galactic supernova explosions. They are initially sources of extreme relativistic electron and/or positron winds (approx.10/sup 38/s/sup -1/ of 10/sup 12/ eV leptons) which greatly decrease as the neutron stars spin down to become mature pulsars. After several million years these neutron stars are no longer observed as radiopulsars, perhaps because of large magnetic field decay. However, a substantial fraction of the 10/sup 8/ old dead pulsars in the Galaxy are the most probable source for the isotropically distributed ..gamma..-ray burst detected several times per week at the earth. Some old neutron stars are spun-up by accretion from companions to be resurrected as rapidly spinning low magnetic field radiopulsars. 52 references, 6 figures, 3 tables.

  5. Understanding the Elusive Dwarf Carbon Star

    E-Print Network [OSTI]

    Paul J. Green

    1996-08-01T23:59:59.000Z

    Most stars in our Galaxy with photospheric C/O>1 (carbon stars) are not giants but dwarfs. The newly-recognized class of dwarf carbon (dC) stars joins the growing family of stars with peculiar abundances that are now recognized as products of mass-transfer binary (MTB) evolution. The dozen examples now known span a wide range of evolutionary histories, ages, and abundances. These stars can already provide some much-needed constraints on the formation of AGB C stars in the disk and spheroid populations, and on the parameters characterizing binary evolution there. A larger sample of dCs, with some bright members, would hasten our progress.

  6. Understanding the dynamical structure of pulsating stars: The Baade-Wesselink projection factor of the delta Scuti stars AI Vel and beta Cas

    E-Print Network [OSTI]

    Guiglion, G; Mathias, P; de Souza, A Domiciano; Poretti, E; Rainer, M; Fokin, A; Mourard, D; Gieren, W; 10.1051/0004-6361/201220780

    2013-01-01T23:59:59.000Z

    Aims. The Baade-Wesselink method of distance determination is based on the oscillations of pulsating stars. The key parameter of this method is the projection factor used to convert the radial velocity into the pulsation velocity. Our analysis was aimed at deriving for the first time the projection factor of delta Scuti stars, using high-resolution spectra of the high-amplitude pulsator AI Vel and of the fast rotator beta Cas. Methods. The geometric component of the projection factor (i.e. p0) was calculated using a limb-darkening model of the intensity distribution for AI Vel, and a fast-rotator model for beta Cas. Then, using SOPHIE/OHP data for beta Cas and HARPS/ESO data for AI Vel, we compared the radial velocity curves of several spectral lines forming at different levels in the atmosphere and derived the velocity gradient associated to the spectral-line-forming regions in the atmosphere of the star. This velocity gradient was used to derive a dynamical projection factor p. Results. We find a flat veloc...

  7. 10-Dim Einstein spaces made up on basis of 6-Dim Ricci-flat spaces and 4-Dim Einstein spaces

    E-Print Network [OSTI]

    Valery Dryuma

    2006-06-09T23:59:59.000Z

    Some examples of ten-dimensional vacuum Einstein spaces made up on basis of four-dimensional Ricci-flat spaces and six-dimensional Ricci-flat spaces defined by solutions of the Sin-Gordon equation are constructed. The properties of geodesics for such type of the spaces are discussed

  8. Quadratic Program based Control of Fully-Actuated Transfemoral Prosthesis for Flat-Ground and Up-Slope Locomotion

    E-Print Network [OSTI]

    Ames, Aaron

    Quadratic Program based Control of Fully-Actuated Transfemoral Prosthesis for Flat-Ground and Up to achieve flat-ground and up-slope walking on a fully-actuated above-knee prosthesis. CLF based quadratic--implemented as a feed-forward term--the end result is a prosthesis controller that utilizes only local information while

  9. Determination of the optimum inclination of a flat solar collector in function of latitude and local climatic data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    569 Determination of the optimum inclination of a flat solar collector in function of latitude of a solar collector, it is necessary to reduce its size to a minimum for a given collected energy of equations described in this work were developed to determine the inclination angle of a . flat solar

  10. Heat Transfer -1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with

    E-Print Network [OSTI]

    Virginia Tech

    Heat Transfer - 1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with dimensions and properties given below. (a) Calculate the solar heat flux (W/m2 is at a distance where the solar heat flux (as defined above) is 500 W/m2 , and the flat plate is oriented

  11. Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column

    E-Print Network [OSTI]

    Chu, Peter C.

    1 1 Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column-coordinate), cylinder's main-axis following coordinate (M-coordinate), and hydrodynamic force following coordinate (F-coordinate system. The hydrodynamic forces (such as the drag and lift forces) and their moments are easily computed

  12. Control structure selection for the deethanizer column from Mongstad/Statoil

    E-Print Network [OSTI]

    Skogestad, Sigurd

    the maxi- mum allowed concentrations of C3 in the distillate is 10% (mol fraction) and the maximum concen, Sigurd Skogestad April 27, 2007 Abstract The selection of a good control structure for a distillation, it is studied the control structure selection of a deethanizer distillation column from Mongstad

  13. Integrated Column Designs for Minimum Energy and Entropy Requirements in Multicomponent Distillation

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Distillation Ivar J. Halvorsen1 and Sigurd Skogestad Norwegian University of Science and Technology, Department at the Topical conference on Separations Technology, Session 23 - Distillation Modeling and Processes II. 2001 Column Designs for Minimum Energy and Entropy Requirements in Multicomponent Distillation Ivar J

  14. Optimization of a Diabatic Distillation Column with Sequential Heat Edward Steven Jimenez and Peter Salamon*

    E-Print Network [OSTI]

    Salamon, Peter

    Optimization of a Diabatic Distillation Column with Sequential Heat Exchangers Edward Steven of Copenhagen, Copenhagen, Denmark Diabatic distillation is a separation process in which heat is transferred is enormous because distillation is the single largest energy degrading unit operation worldwide. Introduction

  15. Optimal Allocation of Heat Exchanger Inventory in a Serial Type Diabatic Distillation Column

    E-Print Network [OSTI]

    Salamon, Peter

    Optimal Allocation of Heat Exchanger Inventory in a Serial Type Diabatic Distillation Column Edward Abstract Diabatic distillation is a separation process in which heat is transferred on the trays inside savings is through diabatic distillation. Instead of just one heat source (the reboiler) and one heat sink

  16. Improving total column ozone retrievals by using cloud pressures derived from Raman scattering in the UV

    E-Print Network [OSTI]

    Joiner, Joanna

    Improving total column ozone retrievals by using cloud pressures derived from Raman scattering resolution, coverage, and sampling of the Aura satellite ozone monitoring instrument (OMI), as compared with the total ozone mapping spectrometer (TOMS) should allow for improved ozone retrievals. By default, the TOMS

  17. Global inventory of nitrogen oxide emissions constrained by space-based observations of NO2 columns

    E-Print Network [OSTI]

    Chance, Kelly

    Global inventory of nitrogen oxide emissions constrained by space-based observations of NO2 columns NO + NO2), and combine these with a priori information from a bottom- up emission inventory (with error and a factor of 2 over remote regions. We derive a top-down NOx emission inventory from the GOME data by using

  18. STREAMLINE is a range of adsorbents and columns designed for expanded bed adsorption.

    E-Print Network [OSTI]

    Lebendiker, Mario

    STREAMLINE is a range of adsorbents and columns designed for expanded bed adsorption. In this new for expanded bed adsorption. They allow: · Capture of biomolecules directly from unclarified feedstocks · High and mechanical stability Principle of expanded bed adsorption The bed is expanded by the upward liquid flow

  19. Circular and Square Concrete Columns Externally Confined by CFRP Composite: Experimental

    E-Print Network [OSTI]

    Boyer, Edmond

    testing of the FRP composite. In existing models for FRP-confined concrete, it is commonly assumedChapter 6 Circular and Square Concrete Columns Externally Confined by CFRP Composite: Experimental limited. This field remains in its developmental stages and more testing and analysis are needed

  20. Collapse of a granular column under rotation J.M. Warnett a,

    E-Print Network [OSTI]

    Thomas, Peter J.

    and geotechni- cal retaining walls. Failure of these containers is analogous to a `dam break' investigated of experiments on the collapse of a granular column [7­11] and the failure of a granular step [5 the theoretical models with the dam break itself. An agricultural application where granular flows are utilised

  1. Column Studies of Anaerobic Carbon Tetrachloride Biotransformation with Hanford Aquifer Material

    E-Print Network [OSTI]

    Semprini, Lewis

    Column Studies of Anaerobic Carbon Tetrachloride Biotransformation with Hanford Aquifer Material bioremediation of carbon tetrachloride (CT) at the Hanford site in south- central Washington state. Benzoate in south- central Washington state has been a defense materials pro- duction complex since 1943. Carbon

  2. Nested Column Generation applied to the Crude Oil Tanker Routing and Scheduling Problem with

    E-Print Network [OSTI]

    Lübbecke, Marco

    Nested Column Generation applied to the Crude Oil Tanker Routing and Scheduling Problem with Split, Germany March 7, 2012 Abstract The split pickup split delivery crude oil tanker routing and scheduling, because of the large expenses in crude oil shipping it is attractive to make use of optimization

  3. Free and forced motion in an asymmetric liquid-column oscillator

    E-Print Network [OSTI]

    Davidson, Fordyce A.

    terrain produces drag and creates a boundary-layer effect, making the tallest buildings particularly is analogous to that of the tuned liquid-column damper used to suppress oscillatory motion in large semi are designed to counteract the oscillatory motion of the building with their own momentum. The first auxiliary

  4. A column generation based label correcting approach for the sensor management in an

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , Information collection, Vehicle Rout- ing Problem, Column generation, Mixed integer linear programming. 1 in complex sensor-to-task assignment problems, which encompass several difficulties. First of all, the tasks and priority rankings. Second, the assignment problem is correlated by many constraint paradigms. Our problem

  5. Black-Box Identification for PLC based MPC of a Binary Distillation Column

    E-Print Network [OSTI]

    Black-Box Identification for PLC based MPC of a Binary Distillation Column B. Huyck ,, F. Logist J is to upgrade the control system with a linear MPC running on a PLC. However, before a model based controller can be used on a PLC, an accurate (but simple) process model has to be constructed. Hence, the aim

  6. Satelliteobservations,AT2 INVERTING GOME FORMALDEHYDE COLUMN FOR BIOGENIC EMISSIONS OVER EUROPE

    E-Print Network [OSTI]

    Curci, Gabriele

    emissions, as opposed to 30% of anthropogenic plus biomass burning contribution.Europe is the only continentSatelliteobservations,AT2 INVERTING GOME FORMALDEHYDE COLUMN FOR BIOGENIC EMISSIONS OVER EUROPE over Europe is generally overestimated by the state-of-the-art chemistry and transport model GEOS

  7. Charge Collection Measurements in single-type column 3D Sensors

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    . Zorzi ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento), Italy G.-F. Dalla Betta were etched by CNM-Barcelona, and the processing into detectors was done by ITC-irst. The columns plane. The detector should be fully efficient. Similar considerations hold for Cz substrates, for which

  8. Lyman $?$ Absorption as a Sensitive Probe of the H I Column in Cooling Flows

    E-Print Network [OSTI]

    Ari Laor

    1996-09-24T23:59:59.000Z

    X-ray spectra of a significant fraction of cooling flow (CF) clusters of galaxies indicate the presence of a large column of ``cold'' absorbing gas. The physical nature of the absorbing medium remains a mystery. Searches for H I absorption using the 21 cm hyperfine structure line yielded null results in most cases. The purpose of this contribution is to point out that the Lyman $\\alpha$ absorption cross section is ~10^7 times larger than for the 21 cm line, it can therefore be used as a very sensitive probe of the H I column in clusters, and can thus place stringent constraints on the nature of the X-ray absorber. This method is applied to the Perseus CF cluster where a medium resolution (~250 km/s) UV spectrum is available. The upper limit on the H I column obtained using Lyman $\\alpha$ is at least ~50 times smaller than the 21 cm detection, and ~5,000 smaller than implied by X-ray spectra, indicating that the X-ray absorber is exceedingly devoid of H I. Higher resolution UV spectra with HST may improve the H I column limits by an additional factor of ~4,000. This method can be applied to strongly constrain the nature of the X-ray absorbing medium in a significant fraction of CF clusters .

  9. Mapping isoprene emissions over North America using formaldehyde column observations from space

    E-Print Network [OSTI]

    Chance, Kelly

    Mapping isoprene emissions over North America using formaldehyde column observations from space. [1] We present a methodology for deriving emissions of volatile organic compounds (VOC) using space to local VOC emissions, with a spatial smearing that increases with the VOC lifetime. Isoprene

  10. Constraining global isoprene emissions with Global Ozone Monitoring Experiment (GOME) formaldehyde column measurements

    E-Print Network [OSTI]

    Chance, Kelly

    Constraining global isoprene emissions with Global Ozone Monitoring Experiment (GOME) formaldehyde emission estimates are highly uncertain because of a lack of direct observations. Formaldehyde (HCHO the observation of this trace gas to help constrain isoprene emissions. We use HCHO column observations from

  11. A Study on Transverse Vibrations in a Column and an Overview of Structural Control

    E-Print Network [OSTI]

    Roldan Arcos, Alejandra 1990-

    2011-07-19T23:59:59.000Z

    of the structure or of specific members to reduce the vibratory responses. It is vital to understand the behavior of the structural members experiencing the vibrations before being able to monitor and control them. Mode shapes show the different movement of columns...

  12. Experimental studies of the transfer phenomena of tritium in an isotope exchange column for recovery tritium

    E-Print Network [OSTI]

    Experimental studies of the transfer phenomena of tritium in an isotope exchange column for recovery tritium Anisia Bornea, Ion Cristescu, Marius Zamfirache, Carmen Varlam National Institute of R processes for tritium separation, is the catalyst isotope exchange water-hydrogen. The main problem

  13. CHEMICAL ENGINEERING Page 1 of 10 PRE-REQUISITES are listed in this column.

    E-Print Network [OSTI]

    Calgary, University of

    be substituted with approval of the Chemical and Petroleum Engineering department and the relevant departmentCHEMICAL ENGINEERING Page 1 of 10 1st YEAR PRE-REQUISITES are listed in this column. CO. All complementary studies courses must be taken prior to graduation. Chemical Engineering: Regular

  14. Hydro International Corals and Water Column Study for Gulf Oil Spill Response

    E-Print Network [OSTI]

    Belogay, Eugene A.

    of NOAA's response to the Deepwater Horizon/BP oil spill. "This is a major catastrophe," said Nelson of Mexico to gather baseline data against which to measure change if oil from the Deepwater Horizon spillHydro International Corals and Water Column Study for Gulf Oil Spill Response 14/07/2010 A science

  15. Liquid-phase thermal diffusion isotope separation apparatus and method having tapered column

    DOE Patents [OSTI]

    Rutherford, W.M.

    1985-12-04T23:59:59.000Z

    A thermal diffusion counterflow method and apparatus for separating isotopes in solution in which the solution is confined in a long, narrow, vertical slit which tapers from bottom to top. The variation in the width of the slit permits maintenance of a stable concentration distribution with relatively long columns, thus permitting isotopic separation superior to that obtained in the prior art.

  16. DIFFUSIVE NUCLEAR BURNING OF HELIUM ON NEUTRON STARS

    SciTech Connect (OSTI)

    Chang, Philip [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Bildsten, Lars [Kavli Institute for Theoretical Physics, Kohn Hall, University of California, Santa Barbara, CA 93106 (United States); Arras, Phil, E-mail: pchang@cita.utoronto.c, E-mail: bildsten@kitp.ucsb.ed, E-mail: pla7y@virginia.ed [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

    2010-11-01T23:59:59.000Z

    Diffusive nuclear burning (DNB) of H by an underlying material capable of capturing protons can readily consume H from the surface of neutron stars (NSs) during their early cooling history. In the absence of subsequent accretion, it will be depleted from the photosphere. We now extend DNB to He, motivated by the recent observation by Ho and Heinke of a carbon atmosphere on the NS in the Cassiopeia A supernova remnant. We calculate the equilibrium structure of He on an underlying {alpha} capturing material, accounting for thermal, mass defect, and Coulomb corrections on the stratification of material with the same zeroth order {mu}{sub e} = A/Z. We show that Coulomb corrections dominate over thermal and mass defect corrections in the highly degenerate part of the envelope. We also show that the bulk of the He sits deep in the envelope rather than near the surface. Thus, even if the photospheric He abundance is low, the total He column could be substantially larger than the photospheric column, which may have implications for rapid surface evolution ({approx}1 yr timescales) of NSs. When nuclear reactions are taken into account, we find that for base temperatures {approx}>1.6 x 10{sup 8} K, He is readily captured onto C. As these high temperatures are present during the early stages of NS evolution, we expect that the primordial He is completely depleted from the NS surface like the case for primordial H. We also find that magnetic fields {approx}<10{sup 12} G do not affect our conclusions. Armed with the results of this work and our prior efforts, we expect that primordial H and He are depleted, and so any observed H or He on the surfaces of these NS must be due to subsequent accretion (with or without spallation). If this subsequent accretion can be prevented, the underlying mid-Z material would be exposed.

  17. Neutron Star Properties with Hyperons

    E-Print Network [OSTI]

    Whittenbury, D L; Thomas, A W; Tsushima, K; Stone, J R

    2012-01-01T23:59:59.000Z

    In the light of the recent discovery of a neutron star with a mass accurately determined to be almost two solar masses, it has been suggested that hyperons cannot play a role in the equation of state of dense matter in $\\beta$-equilibrium. We re-examine this issue in the most recent development of the quark-meson coupling model. Within a relativistic Hartree-Fock approach and including the full tensor structure at the vector-meson-baryon vertices, we find that not only must hyperons appear in matter at the densities relevant to such a massive star but that the maximum mass predicted is completely consistent with the observation.

  18. Nuclear Physics of Neutron Stars

    E-Print Network [OSTI]

    J. Piekarewicz

    2009-01-28T23:59:59.000Z

    Understanding the equation of state (EOS) of cold nuclear matter, namely, the relation between the pressure and energy density, is a central goal of nuclear physics that cuts across a variety of disciplines. Indeed, the limits of nuclear existence, the collision of heavy ions, the structure of neutron stars, and the dynamics of core-collapse supernova, all depend critically on the equation of state of hadronic matter. In this contribution I will concentrate on the special role that nuclear physics plays in constraining the EOS of cold baryonic matter and its impact on the properties of neutron stars.

  19. The Cooling of Compact Stars

    E-Print Network [OSTI]

    Dany Page; Ulrich Geppert; Fridolin Weber

    2005-08-01T23:59:59.000Z

    The cooling of a compact star depends very sensitively on the state of dense matter at supranuclear densities, which essentially controls the neutrino emission, as well as on the structure of the stellar outer layers which control the photon emission. Open issues concern the hyperon population, the presence of meson condensates, superfluidity and superconductivity, and the transition of confined hadronic matter to quark matter. This paper describes these issues and presents cooling calculations based on a broad collection of equations of state for neutron star matter and strange matter. These results are tested against the body of observed cooling data.

  20. Neutron skins and neutron stars

    SciTech Connect (OSTI)

    Piekarewicz, J. [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States)

    2013-11-07T23:59:59.000Z

    The neutron-skin thickness of heavy nuclei provides a fundamental link to the equation of state of neutron-rich matter, and hence to the properties of neutron stars. The Lead Radius Experiment ('PREX') at Jefferson Laboratory has recently provided the first model-independence evidence on the existence of a neutron-rich skin in {sup 208}Pb. In this contribution we examine how the increased accuracy in the determination of neutron skins expected from the commissioning of intense polarized electron beams may impact the physics of neutron stars.

  1. Towards a realistic axion star

    E-Print Network [OSTI]

    J. Barranco; A. Bernal

    2008-08-01T23:59:59.000Z

    In this work we estimate the radius and the mass of a self-gravitating system made of axions. The quantum axion field satisfies the Klein-Gordon equation in a curved space-time and the metric components of this space-time are solutions to the Einstein equations with a source term given by the vacuum expectation value of the energy-momentum operator constructed from the axion field. As a first step towards an axion star we consider the up to the sixth term in the axion potential expansion. We found that axion stars would have masses of the order of asteroids and radius of the order of few centimeters.

  2. Quark stars: their influence on Astroparticle Physics

    E-Print Network [OSTI]

    Sanjay K. Ghosh

    2008-08-12T23:59:59.000Z

    We discuss some of the recent developments in the quark star physics along with the consequences of possible hadron to quark phase transition at high density scenario of neutron stars and their implications on the Astroparticle Physics.

  3. PNM- Energy Star Home Builder Rebate Program

    Broader source: Energy.gov [DOE]

    PNM is offering home builders a rebate for each Energy Star-qualified home they build in PNM service areas. Every Energy Star-qualified home must include effective insulation and air sealing, high...

  4. How to Apply for the ENERGY STAR®

    Broader source: Energy.gov [DOE]

    Join us to learn about applying for ENERGY STAR Certification in Portfolio Manager. Understand the value of the ENERGY STAR certification, see the step-by-step process of applying, and gain tips to...

  5. Equator Appliance: ENERGY STAR Referral (EZ 3720)

    Broader source: Energy.gov [DOE]

    DOE referred Equator Appliance clothes washer EZ 3720 to EPA, brand manager of the ENERGY STAR program, for appropriate action after DOE testing revealed that the model does not meet ENERGY STAR requirements.

  6. Haier: ENERGY STAR Referral (ESA3087)

    Broader source: Energy.gov [DOE]

    DOE referred Haier room air conditioner model ESA3087 to EPA, brand manager of the ENERGY STAR program, for appropriate action after DOE testing revealed that the model does not meet ENERGY STAR requirements.

  7. Small-Column Cesium Ion Exchange Elution Testing of Spherical Resorcinol-Formaldehyde

    SciTech Connect (OSTI)

    Brown, Garrett N.; Russell, Renee L.; Peterson, Reid A.

    2011-10-21T23:59:59.000Z

    This report summarizes the work performed to evaluate multiple, cesium loading, and elution cycles for small columns containing SRF resin using a simple, high-level waste (HLW) simulant. Cesium ion exchange loading and elution curves were generated for a nominal 5 M Na, 2.4E-05 M Cs, 0.115 M Al loading solution traced with 134Cs followed by elution with variable HNO3 (0.02, 0.07, 0.15, 0.23, and 0.28 M) containing variable CsNO3 (5.0E-09, 5.0E-08, and 5.0E-07 M) and traced with 137Cs. The ion exchange system consisted of a pump, tubing, process solutions, and a single, small ({approx}15.7 mL) bed of SRF resin with a water-jacketed column for temperature-control. The columns were loaded with approximately 250 bed volumes (BVs) of feed solution at 45 C and at 1.5 to 12 BV per hour (0.15 to 1.2 cm/min). The columns were then eluted with 29+ BVs of HNO3 processed at 25 C and at 1.4 BV/h. The two independent tracers allowed analysis of the on-column cesium interaction between the loading and elution solutions. The objective of these tests was to improve the correlation between the spent resin cesium content and cesium leached out of the resin in subsequent loading cycles (cesium leakage) to help establish acid strength and purity requirements.

  8. Gas & Stars Aging low-mass stars eject their outer layers.

    E-Print Network [OSTI]

    Barnes, Joshua Edward

    Recycling Gas & Stars #12;Aging low-mass stars eject their outer layers. M57:The Ring Nebula #12;Thor's Emerald Helmet Winds from high-mass stars blow bubbles of hot gas. #12;Supernova blast waves in stars are mixed back into the gas. NGC 6992: Filaments of theVeil Nebula #12;Bubbles blown by high

  9. Black Stars and Gamma Ray Bursts

    E-Print Network [OSTI]

    Tanmay Vachaspati

    2007-06-08T23:59:59.000Z

    Stars that are collapsing toward forming a black hole but are frozen near the Schwarzschild horizon are termed ``black stars''. Collisions of black stars, in contrast to black hole collisions, may be sources of gamma ray bursts, whose basic parameters are estimated quite simply and are found to be consistent with observed gamma ray bursts. Black star gamma ray bursts should be preceded by gravitational wave emission similar to that from the coalescence of black holes.

  10. NuSTAR: Nuclear Spectroscopic Telescope Array

    ScienceCinema (OSTI)

    Craig, Bill

    2014-06-24T23:59:59.000Z

    Bill Craig, an astrophysicist at Lawrence Livermore National Laboratory, describes the NASA NuSTAR mission, launched June 13, 2012.

  11. The nuclear physics of neutron stars

    SciTech Connect (OSTI)

    Piekarewicz, J. [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States)

    2014-05-09T23:59:59.000Z

    We explore the unique and fascinating structure of neutron stars. Although neutron stars are of interest in many areas of Physics, our aim is to provide an intellectual bridge between Nuclear Physics and Astrophysics. We argue against the naive perception of a neutron star as a uniform assembly of neutrons packed to enormous densities. Rather, by focusing on the many exotic phases that are speculated to exist in a neutron star, we show how the reality is different and far more interesting.

  12. Is Her X-1 a strange star?

    E-Print Network [OSTI]

    Jes Madsen

    1996-01-23T23:59:59.000Z

    The possible identification of Her X-1 with a strange star (Li et al. 1995) is shown to be incorrect.

  13. Proceedings of the Flat-Plate Solar Array Project Research Forum on the design of flat-plate photovoltaic arrays for central stations

    SciTech Connect (OSTI)

    None

    1983-01-01T23:59:59.000Z

    The Flat-Plate Solar Array Project, managed by the Jet Propulsion Laboratory for the US Department of Energy, has focused on advancing technologies relevant to the design and construction of megawatt-level central-station systems. Photovoltaic modules and arrays for flat-plate central-station or other large-scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost-effective configurations. The Central Station Research Forum addressed design, qualification and maintenance issues related to central-station arrays derived from the engineering and operating experiences of early applications and parallel laboratory research activities. Technical issues were examined from the viewpoint of the utility engineer, architect-engineer and laboratory researcher. The forum included presentations on optimum source-circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements and array operation and maintenance. The Research Forum focused on current capabilities as well as design difficulties requiring additional technological thrusts and/or continued research emphasis. Session topic summaries highlighting major points during group discussions, identifying promising technical approaches or areas of future research, are presented.

  14. MODELING, IDENTIFICATION AND CONTROL, 2000, VOL. 21, NO. 2, 83103 Evaluation of Dynamic Models of Distillation Columns with Emphasis

    E-Print Network [OSTI]

    Skogestad, Sigurd

    of Distillation Columns with Emphasis on the Initial Response BERND WITTGENS and SIGURD SKOGESTAD* Keywords: Distillation dynamics, tray hydraulics, experimental response The flow dynamics (tray hydraulics) are of key importance for the initial dynamic response of distillation columns. The most important parameters

  15. Can the Operating Leaves of a Distillation Column Really Be Tshepo S. Modise, Michaela Tapp, Diane Hildebrandt,* and David Glasser

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Can the Operating Leaves of a Distillation Column Really Be Expanded? Tshepo S. Modise, Michaela to determine the operation leaves and hence the feasible region for distillation columns operating at a specific distillate and bottoms composition for all possible constant reflux and reboil ratios

  16. Asymmetric Catalysis on Sequentially-Linked Columns Ahmed M. Hafez, Andrew E. Taggi, Travis Dudding, and Thomas Lectka*

    E-Print Network [OSTI]

    Lectka, Thomas

    Asymmetric Catalysis on Sequentially-Linked Columns Ahmed M. Hafez, Andrew E. Taggi, Travis Dudding of a series of "reaction columns". This process was applied to the catalytic asymmetric synthesis of -lactams that they conduct chemical reactions. In regard to chiral synthesis and drug discovery, asymmetric catalysis1

  17. The Chandrasekhar limit for quark stars

    E-Print Network [OSTI]

    Shibaji Banerjee; Sanjay K. Ghosh; Sibaji Raha

    2000-01-14T23:59:59.000Z

    The Chandrasekhar limit for quark stars is evaluated from simple energy balance relations, as proposed by Landau for white dwarfs or neutron stars. It has been found that the limit for quark stars depends on, in addition to the fundamental constants, the Bag constant.

  18. The apsidal motion in close binary stars

    E-Print Network [OSTI]

    B. V. Vasiliev

    2001-10-10T23:59:59.000Z

    It is usually accepted to consider an apsidal motion in binary stars as a direct confirmation that a substance inside stars is not uniformly distributed. It is shown in this paper that the apsidal motion in binary systems observation data is in a good agreement with an existence of uniform plasma cores inside stars if they consist of hydrogen-deuterium-helium mixture.

  19. Carbon stars in populations of different metallicity

    E-Print Network [OSTI]

    M. A. T. Groenewegen

    1998-11-09T23:59:59.000Z

    Our current knowledge of carbon stars in the Local Group and beyond, is discussed. Although many carbon stars and late M-stars have been identified in external galaxies a coherent understanding in terms of the chemical evolution- and star formation rate-history of a galaxy is still largely lacking. Issues that need to be addressed are: 1) for some of the larger galaxies only a small fraction in area has been surveyed so far, 2) surveys have been conducted using different techniques, and may be incomplete in bolometric magnitude, 3) only for some galaxies is there information about the late M-star population, 4) not all galaxies in the Local Group have been surveyed, 5) only for a sub-set of stars are bolometric magnitudes available. From the existing observations one can derive the following: the formation of carbon stars is both a function of metallicity and star-formation. In galaxies with a similar star-formation rate history, there will be relatively more carbon stars formed in the system with the lower metallicity. On the other hand, the scarcity of AGB type carbon stars in some systems with the lowest metallicity indicates that these galaxies have had a low, if any, star-formation rate history over the last few Gyrs.

  20. Maximally incompressible neutron star matter

    E-Print Network [OSTI]

    Timothy S. Olson

    2000-12-07T23:59:59.000Z

    Relativistic kinetic theory, based on the Grad method of moments as developed by Israel and Stewart, is used to model viscous and thermal dissipation in neutron star matter and determine an upper limit on the maximum mass of neutron stars. In the context of kinetic theory, the equation of state must satisfy a set of constraints in order for the equilibrium states of the fluid to be thermodynamically stable and for perturbations from equilibrium to propagate causally via hyperbolic equations. Application of these constraints to neutron star matter restricts the stiffness of the most incompressible equation of state compatible with causality to be softer than the maximally incompressible equation of state that results from requiring the adiabatic sound speed to not exceed the speed of light. Using three equations of state based on experimental nucleon-nucleon scattering data and properties of light nuclei up to twice normal nuclear energy density, and the kinetic theory maximally incompressible equation of state at higher density, an upper limit on the maximum mass of neutron stars averaging 2.64 solar masses is derived.