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Sample records for local condensation experiment

  1. Experiment of flow regime map and local condensing heat transfer coefficients inside three dimensional inner microfin tubes

    Science.gov (United States)

    Du, Yang; Xin, Ming Dao

    1999-03-01

    This paper developed a new type of three dimensional inner microfin tube. The experimental results of the flow patterns for the horizontal condensation inside these tubes are reported in the paper. The flow patterns for the horizontal condensation inside the new made tubes are divided into annular flow, stratified flow and intermittent flow within the test conditions. The experiments of the local heat transfer coefficients for the different flow patterns have been systematically carried out. The experiments of the local heat transfer coefficients changing with the vapor dryness fraction have also been carried out. As compared with the heat transfer coefficients of the two dimensional inner microfin tubes, those of the three dimensional inner microfin tubes increase 47-127% for the annular flow region, 38-183% for the stratified flow and 15-75% for the intermittent flow, respectively. The enhancement factor of the local heat transfer coefficients is from 1.8-6.9 for the vapor dryness fraction from 0.05 to 1.

  2. Scandinavian experience of titanium condensers

    International Nuclear Information System (INIS)

    Multer, I.; Hedstroem, M.

    1985-01-01

    The Albrass condenser tubing in Sweden and Finnish nuclear power plants has caused much concern. After the appearance of the first tube leak, the deterioration has been very rapid. A typical development is represented by the Ringhals unit 2 eddy current (EC) measurements. They are, despite the difference in salinity, almost identical with Forsmark units 1 and 2 and units 1 and 2 of the TVO power company at Olkiluoto, Finland. For instance, in summer 1984, 3000 tubes were plugged in TVO 2 after four years of operation. The cause was pitting and/or erosion-corrosion. The failure rate, although the plugging criteria have been different from the EPRI concept, has exceeded that reported in the US and UK; and it has been necessary, especially with the strict feed water chemistry requirements in the PWR's, to arrange for retubing after a very short time, approximately 3 years after the first leak. The history of the nuclear plant condensers is shown; the average condenser life span has been approximately 6.5 years

  3. Blockage-induced condensation controlled by a local reaction

    Science.gov (United States)

    Cirillo, Emilio N. M.; Colangeli, Matteo; Muntean, Adrian

    2016-10-01

    We consider the setup of stationary zero range models and discuss the onset of condensation induced by a local blockage on the lattice. We show that the introduction of a local feedback on the hopping rates allows us to control the particle fraction in the condensed phase. This phenomenon results in a current versus blockage parameter curve characterized by two nonanalyticity points.

  4. TRACE assessment on local condensation heat transfer in presence of non-condensable gas inside a vertical tube

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Jin; Ahn, Seung Hoon; Kim, Kap; Kim, Hho Jung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2009-07-01

    TRACE assessment was performed to investigate local condensation heat transfer coefficients in the presence of a noncondensable gas inside a vertical tube. The data obtained from pure steam and steam/nitrogen mixture condensation experiments were compared to study the effects of noncondensable nitrogen gas on the annular film condensation phenomena. The condenser tube had a small inner diameter of 13mm (about 1/2-in.) and this experiment had been performed to prove the effectiveness of the a Passive Residual Heat Removal System (PRHRS) of SMART (System-integrated Modular Advanced ReacTor), which is a small modular integral-type pressurized water reactor that is developed for the dual purposes of seawater desalination and small-scaled power generation. In the case of nitrogen presence, TRACE results show the converged results but the prediction is different from experimental data. The candidate reasons can be focused on several models, such as the film thickness calculation, surface area, and condensation heat transfer correlations, etc. In the case of pure steam condensation case, TRACE results shows large oscillations and do not converge. This should be investigated in detail to identify the reason. Until now, the oscillation in thermal hydraulic parameters results from the film thickness calculation and surface area calculation. For future works, the whole sets of the experiment will be assessed and the improvement of TRACE will be performed.

  5. TRACE assessment on local condensation heat transfer in presence of non-condensable gas inside a vertical tube

    International Nuclear Information System (INIS)

    Cho, Yong Jin; Ahn, Seung Hoon; Kim, Kap; Kim, Hho Jung

    2009-01-01

    TRACE assessment was performed to investigate local condensation heat transfer coefficients in the presence of a noncondensable gas inside a vertical tube. The data obtained from pure steam and steam/nitrogen mixture condensation experiments were compared to study the effects of noncondensable nitrogen gas on the annular film condensation phenomena. The condenser tube had a small inner diameter of 13mm (about 1/2-in.) and this experiment had been performed to prove the effectiveness of the a Passive Residual Heat Removal System (PRHRS) of SMART (System-integrated Modular Advanced ReacTor), which is a small modular integral-type pressurized water reactor that is developed for the dual purposes of seawater desalination and small-scaled power generation. In the case of nitrogen presence, TRACE results show the converged results but the prediction is different from experimental data. The candidate reasons can be focused on several models, such as the film thickness calculation, surface area, and condensation heat transfer correlations, etc. In the case of pure steam condensation case, TRACE results shows large oscillations and do not converge. This should be investigated in detail to identify the reason. Until now, the oscillation in thermal hydraulic parameters results from the film thickness calculation and surface area calculation. For future works, the whole sets of the experiment will be assessed and the improvement of TRACE will be performed

  6. Local condensate depletion at trap center under strong interactions

    Science.gov (United States)

    Yukalov, V. I.; Yukalova, E. P.

    2018-04-01

    Cold trapped Bose-condensed atoms, interacting via hard-sphere repulsive potentials are considered. Simple mean-field approximations show that the condensate distribution inside a harmonic trap always has the shape of a hump with the maximum condensate density occurring at the trap center. However, Monte Carlo simulations at high density and strong interactions display the condensate depletion at the trap center. The explanation of this effect of local condensate depletion at trap center is suggested in the frame of self-consistent theory of Bose-condensed systems. The depletion is shown to be due to the existence of the anomalous average that takes into account pair correlations and appears in systems with broken gauge symmetry.

  7. Polariton condensation with localized excitons and propagating photons

    International Nuclear Information System (INIS)

    Keeling, Jonathan; Eastham, P.R.; Szymanska, M.H.; Littlewood, P.B.

    2004-01-01

    We estimate the condensation temperature for microcavity polaritons, allowing for their internal structure. We consider polaritons formed from localized excitons in a planar microcavity, using a generalized Dicke model. At low densities, we find a condensation temperature T c ∝ρ, as expected for a gas of structureless polaritons. However, as T c becomes of the order of the Rabi splitting, the structure of the polaritons becomes relevant, and the condensation temperature is that of a BCS-like mean-field theory. We also calculate the excitation spectrum, which is related to observable quantities such as the luminescence and absorption spectra

  8. Steam blowdown experiments with the condensation pool test rig

    International Nuclear Information System (INIS)

    Purhonen, H.; Puustinen, M.; Laine, J.; Raesaenen, A.; Kyrki-Rajamaeki, R.; Vihavainen, J.

    2005-01-01

    During a possible loss-of-coolant accident (Local) a large amount of non-condensable (nitrogen) and condensable (steam) gas is blown from the upper drywell of the containment to the condensation pool through the blowdown pipes at the boiling water reactors (BWRs). The wet well pool serves as the major heat sink for condensation of steam. The blowdown causes both dynamic and structural loads to the condensation pool. There might also be a risk that the gas discharging to the pool could push its way to the emergency core cooling systems (ECCS) and undermine their performance. (author)

  9. Accident localization system with jet condensers for VVER 440-V 230 NPP at Jaslovske Bohunice

    International Nuclear Information System (INIS)

    Murani, J.

    1995-01-01

    The operational safety of the V1 nuclear power plant (NPP) is unsatisfactory and does not correspond to present requirements as to nuclear safety. Further NPP operation after 1995 is conditional on nuclear safety enhancement to a level comparable with that in West European countries. This aim should be achieved by a principal reconstruction involving in addition to others also backfitting the V1 NPP with technical facilities aimed at coping with a design basis accident (DBA).To cope with such an accident the Power Equipment Research Institute (VUEZ) designed an accident localization system with jet condensers. This system consists of (a) an air trap (one for each unit, mutually interconnected) with an expansion bell enclosed within, placed on a plate with 200 pipes of jet condensers passing through, and (b) a connecting duct between the hermetic zone and the air trap. The vertical jet condenser is an essential element of the system designed for steam condensation. Apart from condensation it serves as a water seal separating units 1 and 2.Demonstration tests of the jet condenser (model 1:1) condensing function were carried out at the testing unit of the All-Union Research Institute for NPP Operation (VNIIAES), Moscow in Kashir, 11-22 September 1992. These experiments proved the jet condenser ability to ensure complete condensation of the steam produced. Experimental verification of the sealing function (model 1:1) was carried out at the testing unit of the VUEZ Tlmace. These experiments concerning the dynamics and overpressure in the free space above the pool were close to the conditions in the air trap during DBA. The jet condenser height was proved to be sufficient to ensure the sealing function. Design and experimental work has been implemented in close cooperation with Russian experts Mr. V.N. Bulynin from the VNIIAES, Moscow, and Mr. M.V. Kuznecov from the Scientific and Engineering Center for Nuclear and Radiological Safety, Moscow. (orig.)

  10. Localized tachyon condensation and G-parity conservation

    International Nuclear Information System (INIS)

    Lee, Sunggeun; Sin, Sang-Jin

    2004-01-01

    We study the condensation of localized tachyon in non-supersymmetric orbifold. We first show that the G-parity of chiral primaries are preserved under the condensation of localized tachyon (CLT). Using this, we finalize the proof of the conjecture that the lowest-tachyon-mass-squared increases under CLT at the level of type II string with full consideration of GSO projection. We also show the equivalence between the G-parity given by G [jk 1 /n]+[jk 2 /n] coming from partition function and that given by G={jk 1 /n}+k 2 -{jk 2 -/n}k 1 coming from the monomial construction for the chiral primaries in the dual Mirror picture. (author)

  11. Condensers

    International Nuclear Information System (INIS)

    Andrieux, M.B.

    1984-01-01

    Characteristics of the condenser cooling waters of various French 900 MW nuclear power plants. Design and description of various types of condensers: condensers feeded directly with river water, condensers feeded by cooling towers, condensers feeded with sea water of brackish water. Presentation of the main problems encountered with the brass bundles (ammoniacal corrosion, erosion of the peripheral tubes, vibrations of the tubes), with the titanium bundles, with the tubular plates, the tubes-tubular plates assemblies, the coatings of the condenser water chamber (sea water), the vapor by-pass and with the air inlet. Analysis of the in service performances such as condensation pressure, oxygen content and availability [fr

  12. The Mott localization and magnetic properties in condensed fermions systems

    International Nuclear Information System (INIS)

    Wojcik, W.

    1995-01-01

    In the present thesis the Mott localization and magnetic properties in condensed fermions system are considered. The Hubbard model has been used to strongly correlated electron systems and the Skyrme potential to a dense neutron matter with small concentration of protons. A variational approach to the metal-insulator transition is proposed which combines the Mott and Gutzwiller-Brinkman-Rice aspects of the localization. Magnetic properties of strongly correlated electrons are analyzed within the modified spin-rotation-invariant approach in the slow-boson representation. The theoretical prediction for considered systems are presented. 112 refs, 39 figs

  13. Condensation pool experiments with steam using DN200 blowdown pipe

    International Nuclear Information System (INIS)

    Laine, J.; Puustinen, M.

    2005-08-01

    This report summarizes the results of the condensation pool experiments with steam using a DN200 blowdown pipe. Altogether five experiment series, each consisting of several steam blows, were carried out in December 2004 with a scaled-down test facility designed and constructed at Lappeenranta University of Technology. The main purpose of the experiments was to increase the understanding of different phenomena in the condensation pool during steam discharge. (au)

  14. Pion condensation and instabilities: current theory and experiment

    International Nuclear Information System (INIS)

    Gyulassy, M.

    1980-05-01

    Current calculations of pion condensation phenomena in symmetric nuclear matter are reviewed. The RPA and MFA methods are compared. Latest results [LBL-10572] with a relativistic MFA theory constrained by bulk nuclear properties are presented. The differences between equilibrium (condensation) and nonequilibrium (dynamic) instabilities are discussed. Finally, two-proton correlation experiments aimed at looking for critical scattering phenomena and two-pion correlation experiments aimed at looking for pion field coherence are analyzed. 10 figures, 2 tables

  15. On Localized Vapor Pressure Gradients Governing Condensation and Frost Phenomena.

    Science.gov (United States)

    Nath, Saurabh; Boreyko, Jonathan B

    2016-08-23

    Interdroplet vapor pressure gradients are the driving mechanism for several phase-change phenomena such as condensation dry zones, interdroplet ice bridging, dry zones around ice, and frost halos. Despite the fundamental nature of the underlying pressure gradients, the majority of studies on these emerging phenomena have been primarily empirical. Using classical nucleation theory and Becker-Döring embryo formation kinetics, here we calculate the pressure field for all possible modes of condensation and desublimation in order to gain fundamental insight into how pressure gradients govern the behavior of dry zones, condensation frosting, and frost halos. Our findings reveal that in a variety of phase-change systems the thermodynamically favorable mode of nucleation can switch between condensation and desublimation depending upon the temperature and wettability of the surface. The calculated pressure field is used to model the length of a dry zone around liquid or ice droplets over a broad parameter space. The long-standing question of whether the vapor pressure at the interface of growing frost is saturated or supersaturated is resolved by considering the kinetics of interdroplet ice bridging. Finally, on the basis of theoretical calculations, we propose that there exists a new mode of frost halo that is yet to be experimentally observed; a bimodal phase map is developed, demonstrating its dependence on the temperature and wettability of the underlying substrate. We hope that the model and predictions contained herein will assist future efforts to exploit localized vapor pressure gradients for the design of spatially controlled or antifrosting phase-change systems.

  16. Disorder-induced trapping versus Anderson localization in Bose-Einstein condensates expanding in disordered potentials

    International Nuclear Information System (INIS)

    Sanchez-Palencia, L; Clement, D; Lugan, P; Bouyer, P; Aspect, A

    2008-01-01

    We theoretically investigate the localization of an expanding Bose-Einstein condensate (BEC) with repulsive atom-atom interactions in a disordered potential. We focus on the regime where the initial inter-atomic interactions dominate over the kinetic energy and the disorder. At equilibrium in a trapping potential and for the considered small disorder, the condensate shows a Thomas-Fermi shape modified by the disorder. When the condensate is released from the trap, a strong suppression of the expansion is obtained in contrast to the situation in a periodic potential with similar characteristics. This effect crucially depends on both the momentum distribution of the expanding BEC and the strength of the disorder. For strong disorder as in the experiments reported by Clement et al 2005 Phys. Rev. Lett. 95 170409 and Fort et al 2005 Phys. Rev. Lett. 95 170410, the suppression of the expansion results from the fragmentation of the core of the condensate and from classical reflections from large modulations of the disordered potential in the tails of the condensate. We identify the corresponding disorder-induced trapping scenario for which large atom-atom interactions and strong reflections from single modulations of the disordered potential play central roles. For weak disorder, the suppression of the expansion signals the onset of Anderson localization, which is due to multiple scattering from the modulations of the disordered potential. We compute analytically the localized density profile of the condensate and show that the localization crucially depends on the correlation function of the disorder. In particular, for speckle potentials the long-range correlations induce an effective mobility edge in 1D finite systems. Numerical calculations performed in the mean-field approximation support our analysis for both strong and weak disorder

  17. Comparison of condensation correlations in CATHARE for modelling isolation condenser experiment

    International Nuclear Information System (INIS)

    Sorjonen, J.; Kalli, H.

    1996-01-01

    CATHARE is a thermal-hydraulic computer code developed at the Centre d'Etudes Nucleaires de Grenoble (CENG) for nuclear power plant safety analysis. Behaviour of a new Cathare condensation correlation have been studied. The code has been applied to Isolation Condenser (IC) experiment conducted in PIPER-ONE facility. PIPER-ONE simulates a General Electric BWR-6 with volume and height scaling ratios 1/2200 and 1/1, respectively. The facility is installed at Dipartimento di Costruzioni Meccaniche e Nucleari of Pisa University. The facility was equipped with an once-through heat exchanger immersed in a pool of ambient temperature water, installed roughly 10 m above the core, in the aim to reproduce qualitatively the phenomenologies expected for Isolation Condenser in the Simplified BWR (SBWR). Experiment PO-IC-02 included two subsequent power levels with initial pressure of 5.1 MPa. The IC was active during the whole experiment except in the time period between the two different power levels. A previous calculation of above mentioned experiment by Cathare2 V1.3E showed some lacks in the condensation correlation of the code. A new correlation has been developed in Centre d'Etudes Nucleaires de Grenoble (CENG). The new calculation of the PO-IC-02 experiment by Cathare2 Vl.3U 1 with the new correlation gave results consistent with the experiment in the condensing zone of the IC. Also the overall pressure trend was reproduced with estimated heat losses to the environment. A comparison with previously obtained Relap5/Mod3. 1 results is also shown in the present document. (author) (18 refs.)

  18. A microgravity boiling and convective condensation experiment

    Science.gov (United States)

    Kachnik, Leo; Lee, Doojeong; Best, Frederick; Faget, Nanette

    1987-12-01

    A boiling and condensing test article consisting of two straight tube boilers, one quartz and one stainless steel, and two 1.5 m long glass-in-glass heat exchangers, on 6 mm ID and one 10 mm ID, was flown on the NASA KC-135 0-G aircraft. Using water as the working fluid, the 5 kw boiler produces two phase mixtures of varying quality for mass flow rates between 0.005 and 0.1 kg/sec. The test section is instrumented at eight locations with absolute and differential pressure transducers and thermocouples. A gamma densitometer is used to measure void fraction, and high speed photography records the flow regimes. A three axis accelerometer provides aircraft acceleration data (+ or - 0.01G). Data are collected via an analog-to-digital conversion and data acquisition system. Bubbly, annular, and slug flow regimes were observed in the test section under microgravity conditions. Flow oscillations were observed for some operating conditions and the effect of the 2-G pullout prior to the 0-G period was observed by continuously recording data throughout the parabolas. A total fo 300 parabolas was flown.

  19. Condensation on superhydrophobic surfaces: the role of local energy barriers and structure length scale.

    Science.gov (United States)

    Enright, Ryan; Miljkovic, Nenad; Al-Obeidi, Ahmed; Thompson, Carl V; Wang, Evelyn N

    2012-10-09

    Water condensation on surfaces is a ubiquitous phase-change process that plays a crucial role in nature and across a range of industrial applications, including energy production, desalination, and environmental control. Nanotechnology has created opportunities to manipulate this process through the precise control of surface structure and chemistry, thus enabling the biomimicry of natural surfaces, such as the leaves of certain plant species, to realize superhydrophobic condensation. However, this "bottom-up" wetting process is inadequately described using typical global thermodynamic analyses and remains poorly understood. In this work, we elucidate, through imaging experiments on surfaces with structure length scales ranging from 100 nm to 10 μm and wetting physics, how local energy barriers are essential to understand non-equilibrium condensed droplet morphologies and demonstrate that overcoming these barriers via nucleation-mediated droplet-droplet interactions leads to the emergence of wetting states not predicted by scale-invariant global thermodynamic analysis. This mechanistic understanding offers insight into the role of surface-structure length scale, provides a quantitative basis for designing surfaces optimized for condensation in engineered systems, and promises insight into ice formation on surfaces that initiates with the condensation of subcooled water.

  20. Local-order metric for condensed-phase environments

    Science.gov (United States)

    Martelli, Fausto; Ko, Hsin-Yu; Oǧuz, Erdal C.; Car, Roberto

    2018-02-01

    We introduce a local order metric (LOM) that measures the degree of order in the neighborhood of an atomic or molecular site in a condensed medium. The LOM maximizes the overlap between the spatial distribution of sites belonging to that neighborhood and the corresponding distribution in a suitable reference system. The LOM takes a value tending to zero for completely disordered environments and tending to one for environments that perfectly match the reference. The site-averaged LOM and its standard deviation define two scalar order parameters, S and δ S , that characterize with excellent resolution crystals, liquids, and amorphous materials. We show with molecular dynamics simulations that S , δ S , and the LOM provide very insightful information in the study of structural transformations, such as those occurring when ice spontaneously nucleates from supercooled water or when a supercooled water sample becomes amorphous upon progressive cooling.

  1. Experience with titanium condensers in Belgian nuclear power plants

    International Nuclear Information System (INIS)

    Laire, C.; Graeve, R. de; Comptdaer, Y.; Gilbert, P.

    2006-01-01

    At Tihange, one unit is equipped with a replaced condenser in titanium, although the cooling water is less aggressive compared to Doel. At some units, small leaks have occurred during service and the causes of these leaks could be related to the following mechanisms: Steam droplet erosion at the tube outer surface; inspections with eddy current and a visual inspection have drastically reduced the occurrence of small leaks at the Tihange 1 unit. Mechanical wear due to foreign objects blocking the tube entrance on the raw water side. Small debris coming from the cooling tower has generated wear and this type of degradation has resulted in the installation of protective short sleeves at one unit (Doel 4). After 8 years of operation with these sleeves, the absence of degradation was verified on pulled tubes. Despite the aggressive water, no corrosion under the sleeves has occurred, and erosion behind the sleeves - possibly due to local turbulence - has not been observed. This experience confirms the excellent corrosion resistance of titanium. The paper summarizes the results of the different inspections and investigations on pulled tubes. (orig.)

  2. Extracting the Condensate Density from Projection Experiments with Fermi Gases

    International Nuclear Information System (INIS)

    Perali, A.; Pieri, P.; Strinati, G.C.

    2005-01-01

    A debated issue in the physics of the BCS-BEC crossover with trapped Fermi atoms is to identify characteristic properties of the superfluid phase. Recently, a condensate fraction was measured on the BCS side of the crossover by sweeping the system in a fast (nonadiabatic) way from the BCS to the Bose-Einstein condensation (BEC) sides, thus 'projecting' the initial many-body state onto a molecular condensate. We analyze here the theoretical implications of these projection experiments, by identifying the appropriate quantum-mechanical operator associated with the measured quantities and relating them to the many-body correlations occurring in the BCS-BEC crossover. Calculations are presented over wide temperature and coupling ranges, by including pairing fluctuations on top of the mean field

  3. A Local Condensation Analysis Representing Two-phase Annular Flow in Condenser/radiator Capillary Tubes

    Science.gov (United States)

    Karimi, Amir

    1991-01-01

    NASA's effort for the thermal environmental control of the Space Station Freedom is directed towards the design, analysis, and development of an Active Thermal Control System (ATCS). A two phase, flow through condenser/radiator concept was baselined, as a part of the ATCS, for the radiation of space station thermal load into space. The proposed condenser rejects heat through direct condensation of ATCS working fluid (ammonia) in the small diameter radiator tubes. Analysis of the condensation process and design of condenser tubes are based on the available two phase flow models for the prediction of flow regimes, heat transfer, and pressure drops. The prediction formulas use the existing empirical relationships of friction factor at gas-liquid interface. An attempt is made to study the stability of interfacial waves in two phase annular flow. The formulation is presented of a stability problem in cylindrical coordinates. The contribution of fluid viscosity, surface tension, and transverse radius of curvature to the interfacial surface is included. A solution is obtained for Kelvin-Helmholtz instability problem which can be used to determine the critical and most dangerous wavelengths for interfacial waves.

  4. Interferometer tests for quantum non-locality using Bose-Einstein condensates

    Energy Technology Data Exchange (ETDEWEB)

    Mullin, W J [Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Laloe, F [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France)], E-mail: mullin@physics.umass.edu, E-mail: laloe@lkb.ens.fr

    2009-02-01

    In conventional Einstein-Rosen-Podolsky (EPR) experiments that violate local realism, particles are placed in very particular entangled states. We propose here to use two or three spinless Fock-state Bose-Einstein condensates as independent sources in interferometery experiments. While these states do not seem to be entangled, nevertheless we show that interferometers can be constructed that demonstrate a large variety of different violations local reality. We find violations of Bell inequalities, new Greenberger-Horne-Zeilinger (GHZ) contradictions, and Hardy impossibilities. These violations continue to arbitrarily large particle numbers. A necessary condition to observe the quantum effects is that all particles should be observed; if some are missed, the quantum effects disappear.

  5. Condensation during gravity driven ECC: Experiments with PACTEL

    Energy Technology Data Exchange (ETDEWEB)

    Munther, R.; Kalli, H. [Lappeenranta Univ. of Technology (Finland); Kouhia, J. [Technical Research Centre of Finland, Lappeenranta (Finland)

    1995-09-01

    This paper provides the results of the second series of gravity driven emergency core cooling (ECC) experiments with PACTEL (Parallel Channel Test Loop). The simulated accident was a small break loss-of-coolant accident (SBLOCA) with a break in a cold leg. The ECC flow was provided from a core makeup tank (CMT) located at a higher elevation than the main part of the primary system. The CMT was pressurized with pipings from the pressurizer and a cold leg. The tests indicated that steam condensation in the CMT can prevent ECC and lead to core uncovery.

  6. Assessment of RELAP5/MOD3 with condensation experiment for pure steam condensation in a vercal tube

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Jae; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1999-12-31

    The film condensation models in RELAP5/MOD3.1 and RELAP5/MOD3.2 are assessed with the data of experiment performed in the scaled down condensation experimental facility with a single vertical tube of inner diameter of 46 mm in the range of pressure 0.1 {approx} 7.5 MPa for the PSCS(Passive Secondary Condenser System). Both MOD3.1 and MOD3.2 don`t shows any reliable predictions of the experimental data. The RELAP5/MOD3.1 overpredicts the heat transfer coefficients of experiment, whereas the RELAP5/MOD3.2 underpredicts those data. It is recommended that the film condensation model in RELAP5/MOD3.2 should be modified to have a larger heat transfer coefficient than those of the present model to give the reliable predictions. 7 refs., 6 figs., 1 tab. (Author)

  7. Assessment of RELAP5/MOD3 with condensation experiment for pure steam condensation in a vercal tube

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Jae; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    The film condensation models in RELAP5/MOD3.1 and RELAP5/MOD3.2 are assessed with the data of experiment performed in the scaled down condensation experimental facility with a single vertical tube of inner diameter of 46 mm in the range of pressure 0.1 {approx} 7.5 MPa for the PSCS(Passive Secondary Condenser System). Both MOD3.1 and MOD3.2 don`t shows any reliable predictions of the experimental data. The RELAP5/MOD3.1 overpredicts the heat transfer coefficients of experiment, whereas the RELAP5/MOD3.2 underpredicts those data. It is recommended that the film condensation model in RELAP5/MOD3.2 should be modified to have a larger heat transfer coefficient than those of the present model to give the reliable predictions. 7 refs., 6 figs., 1 tab. (Author)

  8. Disorder Induced Dynamic Equilibrium Localization and Random Phase Steps of Bose—Einstein Condensates

    International Nuclear Information System (INIS)

    Duan Ya-Fan; Xu Zhen; Qian Jun; Sun Jian-Fang; Jiang Bo-Nan; Hong Tao

    2011-01-01

    We numerically analyze the dynamic behavior of Bose—Einstein condensate (BEC) in a one-dimensional disordered potential before it completely loses spatial quantum coherence. We find that both the disorder statistics and the atom interactions produce remarkable effects on localization. We also find that the single phase of the initial condensate is broken into many small pieces while the system approaches localization, showing a counter-intuitive step-wise phase but not a thoroughly randomized phase. Although the condensates as a whole show less flow and expansion, the currents between adjacent phase steps retain strong time dependence. Thus we show explicitly that the localization of a finite size Bose—Einstein condensate is a dynamic equilibrium state. (general)

  9. Symmetry breaking in a localized interacting binary Bose-Einstein condensate in a bichromatic optical lattice

    International Nuclear Information System (INIS)

    Cheng Yongshan; Adhikari, S. K.

    2010-01-01

    By direct numerical simulation of the time-dependent Gross-Pitaevskii equation using the split-step Fourier spectral method, we study different aspects of the localization of a cigar-shaped interacting binary (two-component) Bose-Einstein condensate (BEC) in a one-dimensional bichromatic quasiperiodic optical-lattice potential, as used in a recent experiment on the localization of a BEC [Roati et al., Nature 453, 895 (2008)]. We consider two types of localized states: (i) when both localized components have a maximum of density at the origin x=0, and (ii) when the first component has a maximum of density and the second a minimum of density at x=0. In the noninteracting case, the density profiles are symmetric around x=0. We numerically study the breakdown of this symmetry due to interspecies and intraspecies interactions acting on the two components. Where possible, we have compared the numerical results with a time-dependent variational analysis. We also demonstrate the stability of the localized symmetry-broken BEC states under small perturbation.

  10. Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

    Energy Technology Data Exchange (ETDEWEB)

    Buschman, Francis X., E-mail: Francis.Buschman@unnpp.gov; Aumiller, David L.

    2017-02-15

    Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

  11. Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

    International Nuclear Information System (INIS)

    Buschman, Francis X.; Aumiller, David L.

    2017-01-01

    Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

  12. Intrinsic localized modes in arrays of atomic-molecular Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Abdullaev, F.Kh.; Konotop, V.V.

    2003-01-01

    The existence of strongly localized matter solitons, intrinsic localized modes (ILM's), in an array of atomic-molecular Bose-Einstein condensates (AMBEC's) is shown. The theory is based on the Wannier function expansion of the system order parameter and predicts the possibility of strong localization of the atomic and molecular components whose relative populations are determined by the Raman detuning parameter and by the atom-molecule conversion rate. ILM's can possess different symmetries and spatial distributions of the components. In this context AMBEC arrays can be viewed as potential compressors and separators of atomic and molecular condensates

  13. Multiple condensation induced water hammer events, experiments and theoretical investigations

    International Nuclear Information System (INIS)

    Barna, Imre Ferenc; Ezsoel, Gyoergy

    2011-01-01

    We investigate steam condensation induced water hammer (CIWH) phenomena and present experimental and theoretical results. Some of the experiments were performed in the PMK-2 facility, which is a full-pressure thermalhydraulic model of the nuclear power plant of VVER-440/312 type and located in the Atomic Energy Research Institute Budapest, Hungary. Other experiments were done in the ROSA facility in Japan. On the theoretical side CIWH is studied and analyzed with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shockcapturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to RELAP5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. New features are the existence of multiple, independent CIWH pressure peaks both in experiments and in simulations. Experimentally measured and theoretically calculated CIWH pressure peaks are in qualitative agreement. However, the computational results are very sensitive against flow velocity. (orig.)

  14. Condensation induced water hammer. Overview and own experiments

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan; Doerfler, Michael; Kulisch, Helmut; Malcherek, Andreas

    2012-01-01

    A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this phenomenon and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (orig.)

  15. Condensation-induced water hammer - overview and own experiments

    International Nuclear Information System (INIS)

    Dirndorfer, S.; Doerfler, M.; Kulisch, H.; Malcherek, A.

    2011-01-01

    A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this effect and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (author)

  16. Analysis of experiments for vertical out-tube steam condensation in presence of non-condensable gases

    International Nuclear Information System (INIS)

    Su Jiqiang; Sun Zhongning; Fan Guangming; Guo Zixuan

    2014-01-01

    In order to investigate the influence of various parameters in the steam condensation heat transfer process with non-condensable gas, and to get a more suitable empirical correlation, the wall under-cooling, pressure and the content of non-condensable gas were studied outside a vertical tube by experiments. The results showed that: at the same pressure, the relationship between wall sub-cooling and HTC is exponential, and helium stratification does not happen within the experimental range. Based on the analysis of various experimental variables, combined with a large number of experimental data, a wider scope of application of the empirical correlation associated is obtained with the experimental value of the error within ±20%. (authors)

  17. Condensate localization by mesoscale disorder in high-Tc superconductors

    International Nuclear Information System (INIS)

    Kumar, N.

    1994-06-01

    We propose and solve approximately a phenomenological model for Anderson localization of the macroscopic wavefunction for an inhomogeneous superconductor quench-disordered on the mesoscale of the order of the coherence length ξ 0 . Our treatment is based on the non-linear Schroedinger equation resulting from the Ginzburg-Landau free-energy functional having a spatially random coefficient representing spatial disorder of the pairing interaction. Linearization of the equation, valid close to the critical temperature T c , or to the upper critical field H c2 (T c ) maps it to the Anderson localization problem with T c identified with the mobility edge. For the highly anisotropic high-T c materials and thin (2D) films in the quantum Hall geometry, we predict windows of re-entrant superconductivity centered at integrally spaced temperature values. Our model treatment also provides a possible explanation for the critical current J c perpendicular becoming non-zero on cooling before J c parallel does in some high-T c superconductors. (author). 18 refs

  18. Development of passive condensers for accident localization systems at nuclear power plants in the former USSR

    International Nuclear Information System (INIS)

    Kuznecov, M.V.

    1992-01-01

    The development is summarized of passive condensers for accident localization systems at nuclear power plants (with RBMK and WWER reactors) in the former USSR. Basic properties and criteria defining their availability are described, as are experimental tests and technical solution optimization results. (author) 2 fig

  19. Fire Danger of Interaction Processes of Local Sources with a Limited Energy Capacity and Condensed Substances

    OpenAIRE

    Glushkov, Dmitry Olegovich; Strizhak, Pavel Alexandrovich; Vershinina, Kseniya Yurievna

    2015-01-01

    Numerical investigation of flammable interaction processes of local energy sources with liquid condensed substances has been carried out. Basic integrated characteristic values of process have been defined – ignition delay time at different energy sources parameters. Recommendations have been formulated to ensure fire safety of technological processes, characterized by possible local heat sources formation (cutting, welding, friction, metal grinding etc.) in the vicinity of storage areas, tra...

  20. Fire Danger of Interaction Processes of Local Sources with a Limited Energy Capacity and Condensed Substances

    Directory of Open Access Journals (Sweden)

    Glushkov Dmitrii O.

    2015-01-01

    Full Text Available Numerical investigation of flammable interaction processes of local energy sources with liquid condensed substances has been carried out. Basic integrated characteristic values of process have been defined – ignition delay time at different energy sources parameters. Recommendations have been formulated to ensure fire safety of technological processes, characterized by possible local heat sources formation (cutting, welding, friction, metal grinding etc. in the vicinity of storage areas, transportation, transfer and processing of flammable liquids (gasoline, kerosene, diesel fuel.

  1. Design optimization of condenser microphone: a design of experiment perspective.

    Science.gov (United States)

    Tan, Chee Wee; Miao, Jianmin

    2009-06-01

    A well-designed condenser microphone backplate is very important in the attainment of good frequency response characteristics--high sensitivity and wide bandwidth with flat response--and low mechanical-thermal noise. To study the design optimization of the backplate, a 2(6) factorial design with a single replicate, which consists of six backplate parameters and four responses, has been undertaken on a comprehensive condenser microphone model developed by Zuckerwar. Through the elimination of insignificant parameters via normal probability plots of the effect estimates, the projection of an unreplicated factorial design into a replicated one can be performed to carry out an analysis of variance on the factorial design. The air gap and slot have significant effects on the sensitivity, mechanical-thermal noise, and bandwidth while the slot/hole location interaction has major influence over the latter two responses. An organized and systematic approach of designing the backplate is summarized.

  2. Operational experiences with on line BWR condenser tube leak verification

    International Nuclear Information System (INIS)

    Bryant, R.A.; Duvall, W.E.; Kirkley, W.B.; Zavadoski, R.W.

    1988-01-01

    Verifying condenser tube leaks at a boiling water reactor is, at best, a difficult task carried out in hot steamy water boxes with concurrent radiation exposure. For small apparent leaks with slight chemical changes there is always uncertainty of whether the problem is a condenser tube leak or a feedback from radwaste. Most conventional methods (e.g soap tests, Saran wrap suction, and helium tests) usually involve a load reduction to isolate the water boxes one at a time and hours of drain down on each box. The sensitivity of the most sensitive test (helium) is of the order of 7500 l per day per box. Sulfur hexafluoride has been successfully used at a BWR to identify one leaking water box out of four while the unit was at 100 % power. The actual tubes leakig in the water box were identified by injecting helium during drain down of the box and subsequent manifold testing. Additional tests with sulfur hexafluoride on the second BWR unit indicated tight water boxes to within the sensitivity of the measurement, i.e. less than 19 l per day for all four boxes. Problems encountered in both tests included sulfur hexafluoride carry over from the plume of the cooling towers and off gas considerations. In brief sulfur hexafluoride can be used to quickly identify which particular water box has a condenser tube leak or, just as quickly, establish the integrity of all the water boxes to a level not previously attainable. (author)

  3. Light Condensation and Localization in Disordered Photonic Media: Theory and Large Scale ab initio Simulations

    KAUST Repository

    Toth, Laszlo Daniel

    2013-05-07

    Disordered photonics is the study of light in random media. In a disordered photonic medium, multiple scattering of light and coherence, together with the fundamental principle of reciprocity, produce a wide range of interesting phenomena, such as enhanced backscattering and Anderson localization of light. They are also responsible for the existence of modes in these random systems. It is known that analogous processes to Bose-Einstein condensation can occur in classical wave systems, too. Classical condensation has been studied in several contexts in photonics: pulse formation in lasers, mode-locking theory and coherent emission of disordered lasers. All these systems have the common theme of possessing a large ensemble of waves or modes, together with nonlinearity, dispersion or gain. In this work, we study light condensation and its connection with light localization in a disordered, passive dielectric medium. We develop a theory for the modes inside the disordered resonator, which combines the Feshbach projection technique with spin-glass theory and statistical physics. In particular, starting from the Maxwell’s equations, we map the system to a spherical p-spin model with p = 2. The spins are replaced by modes and the temperature is related to the fluctuations in the environment. We study the equilibrium thermodynamics of the system in a general framework and show that two distinct phases exist: a paramagnetic phase, where all the modes are randomly oscillating and a condensed phase, where the energy condensates on a single mode. The thermodynamic quantities can be explicitly interpreted and can also be computed from the disorder-averaged time domain correlation function. We launch an ab initio simulation campaign using our own code and the Shaheen supercomputer to test the theoretical predictions. We construct photonic samples of varying disorder and find computationally relevant ways to obtain the thermodynamic quantities. We observe the phase transition

  4. Disordered-quantum-walk-induced localization of a Bose-Einstein condensate

    International Nuclear Information System (INIS)

    Chandrashekar, C. M.

    2011-01-01

    We present an approach to induce localization of a Bose-Einstein condensate in a one-dimensional lattice under the influence of unitary quantum-walk evolution using disordered quantum coin operation. We introduce a discrete-time quantum-walk model in which the interference effect is modified to diffuse or strongly localize the probability distribution of the particle by assigning a different set of coin parameters picked randomly for each step of the walk, respectively. Spatial localization of the particle or state is explained by comparing the variance of the probability distribution of the quantum walk in position space using disordered coin operation to that of the walk using an identical coin operation for each step. Due to the high degree of control over quantum coin operation and most of the system parameters, ultracold atoms in an optical lattice offer opportunities to implement a disordered quantum walk that is unitary and induces localization. Here we present a scheme to use a Bose-Einstein condensate that can be evolved to the superposition of its internal states in an optical lattice and control the dynamics of atoms to observe localization. This approach can be adopted to any other physical system in which controlled disordered quantum walk can be implemented.

  5. Experimental and theoretical analysis of the local condensation heat transfer in a plate heat exchanger

    International Nuclear Information System (INIS)

    Grabenstein, V; Kabelac, S

    2012-01-01

    Plate heat exchanger (PHE) are today widely used in industrial heat transfer applications due to their good thermal performance, modest space requirement, easy accessibility to all areas and their lower capital and operating costs as compared to shell-and-tube heat exchangers. Although authoritative models for the design of PHE used as condensers are missing, the number of applications where a PHE is operating as a condenser increases. On the way to a reliable model based on physical approaches for the prediction of heat transfer and pressure drop during the condensation process inside a PHE, the flow and heat interactions as well as their dependence on the geometrical parameters of the corrugated plates and the operating conditions must be studied in detail. In this work the stepwise procedure for the fundamental construction of such a model is described. An experimental setup was built to analyze the characteristics of the two-phase-flow in PHE. A single gap, consisting of two transparent corrugated plates, was tested with a two-phase flow of air/water and also with boiling refrigerant R365mfc. Flow pattern maps were constructed for plates with corrugation angles of 27 and 63 degrees relative to the direction of flow. Investigations of the local heat transfer coefficients and the pressure drop were done with the same plates. The measurement of the local heat transfer coefficients was carried out by the use of the 'Temperature Oscillation InfraRed Thermography' (TOIRT) method. Based on these results three main flow patterns are defined: film flow, bubbly flow and slug flow. For each of the three flow patterns an own model for the heat transfer and pressure drop mechanism are developed and the heat transfer coefficient and the friction factor is calculated with different equations depending on the actual steam quality, mass flow and geometrical parameters by means of a flow pattern map. The theory of the flow pattern based prediction models is proved with own

  6. Localized nonlinear waves and dynamical stability in spinor Bose–Einstein condensates with time–space modulation

    Science.gov (United States)

    Yao, Yu-Qin; Han, Wei; Li, Ji; Liu, Wu-Ming

    2018-05-01

    Nonlinearity is one of the most remarkable characteristics of Bose–Einstein condensates (BECs). Much work has been done on one- and two-component BECs with time- or space-modulated nonlinearities, while there is little work on spinor BECs with space–time-modulated nonlinearities. In the present paper we investigate localized nonlinear waves and dynamical stability in spinor Bose–Einstein condensates with nonlinearities dependent on time and space. We solve the three coupled Gross–Pitaevskii equations by similarity transformation and obtain two families of exact matter wave solutions in terms of Jacobi elliptic functions and the Mathieu equation. The localized states of the spinor matter wave describe the dynamics of vector breathing solitons, moving breathing solitons, quasi-breathing solitons and resonant solitons. The results show that one-order vector breathing solitons, quasi-breathing solitons, resonant solitons and the moving breathing solitons ψ ±1 are all stable, but the moving breathing soliton ψ 0 is unstable. We also present the experimental parameters to realize these phenomena in future experiments.

  7. Nonlinear localized modes in dipolar Bose–Einstein condensates in two-dimensional optical lattices

    International Nuclear Information System (INIS)

    Rojas-Rojas, Santiago; Naether, Uta; Delgado, Aldo; Vicencio, Rodrigo A.

    2016-01-01

    Highlights: • We study discrete two-dimensional breathers in dipolar Bose–Einstein Condensates. • Important differences in the properties of three fundamental modes are found. • Norm threshold for existence of 2D breathers varies with dipolar interaction. • The Effective Potential Method is implemented for stability analysis. • Uncommon mobility of 2D discrete solitons is observed. - Abstract: We analyze the existence and properties of discrete localized excitations in a Bose–Einstein condensate loaded into a periodic two-dimensional optical lattice, when a dipolar interaction between atoms is present. The dependence of the Number of Atoms (Norm) on the energy of solutions is studied, along with their stability. Two important features of the system are shown, namely, the absence of the Norm threshold required for localized solutions to exist in finite 2D systems, and the existence of regions in the parameter space where two fundamental solutions are simultaneously unstable. This feature enables mobility of localized solutions, which is an uncommon feature in 2D discrete nonlinear systems. With attractive dipolar interaction, a non-trivial behavior of the Norm dependence is obtained, which is well described by an analytical model.

  8. Nonlinear localized modes in dipolar Bose–Einstein condensates in two-dimensional optical lattices

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Rojas, Santiago, E-mail: srojas@cefop.cl [Center for Optics and Photonics and MSI-Nucleus on Advanced Optics, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Naether, Uta [Instituto de Ciencia de Materiales de Aragón and Departamento de Física de la Materia Condensada, CSIC-Universidad de Zaragoza, 50009 Zaragoza (Spain); Delgado, Aldo [Center for Optics and Photonics and MSI-Nucleus on Advanced Optics, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Vicencio, Rodrigo A. [Center for Optics and Photonics and MSI-Nucleus on Advanced Optics, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Departamento de Física, Facultad de Ciencias, Universidad de Chile, Santiago (Chile)

    2016-09-16

    Highlights: • We study discrete two-dimensional breathers in dipolar Bose–Einstein Condensates. • Important differences in the properties of three fundamental modes are found. • Norm threshold for existence of 2D breathers varies with dipolar interaction. • The Effective Potential Method is implemented for stability analysis. • Uncommon mobility of 2D discrete solitons is observed. - Abstract: We analyze the existence and properties of discrete localized excitations in a Bose–Einstein condensate loaded into a periodic two-dimensional optical lattice, when a dipolar interaction between atoms is present. The dependence of the Number of Atoms (Norm) on the energy of solutions is studied, along with their stability. Two important features of the system are shown, namely, the absence of the Norm threshold required for localized solutions to exist in finite 2D systems, and the existence of regions in the parameter space where two fundamental solutions are simultaneously unstable. This feature enables mobility of localized solutions, which is an uncommon feature in 2D discrete nonlinear systems. With attractive dipolar interaction, a non-trivial behavior of the Norm dependence is obtained, which is well described by an analytical model.

  9. Assessment of GOTHIC and TRACE codes against selected PANDA experiments on a Passive Containment Condenser

    Energy Technology Data Exchange (ETDEWEB)

    Papini, Davide, E-mail: davide.papini@psi.ch; Adamsson, Carl; Andreani, Michele; Prasser, Horst-Michael

    2014-10-15

    Highlights: • Code comparison on the performance of a Passive Containment Condenser. • Simulation of separate effect tests with pure steam and non-condensable gases. • Role of the secondary side and accuracy of pool boiling models are discussed. • GOTHIC and TRACE predict the experimental performance with slight underestimation. • Recirculatory flow pattern with injection of light non-condensable gas is inferred. - Abstract: Typical passive safety systems for ALWRs (Advanced Light Water Reactors) rely on the condensation of steam to remove the decay heat from the core or the containment. In the present paper the three-dimensional containment code GOTHIC and the one-dimensional system code TRACE are compared on the calculation of a variety of phenomena characterizing the response of a passive condenser submerged in a boiling pool. The investigation addresses the conditions of interest for the Passive Containment Cooling System (PCCS) proposed for the ESBWR (Economic Simplified Boiling Water Reactor). The analysis of selected separate effect tests carried out on a PCC (Passive Containment Condenser) unit in the PANDA large-scale thermal-hydraulic facility is presented to assess the code predictions. Both pure steam conditions (operating pressure of 3 bar, 6 bar and 9 bar) and the effect on the condensation heat transfer of non-condensable gases heavier than steam (air) and lighter than steam (helium) are considered. The role of the secondary side (pool side) heat transfer on the condenser performance is examined too. In general, this study shows that both the GOTHIC and TRACE codes are able to reasonably predict the heat transfer capability of the PCC as well as the influence of non-condensable gas on the system. A slight underestimation of the condenser performance is obtained with both codes. For those tests where the experimental and simulated efficiencies agree better the possibility of compensating errors among different parts of the heat transfer

  10. Performance Evaluation of the International Space Station Flow Boiling and Condensation Experiment (FBCE) Test Facility

    Science.gov (United States)

    Hasan, Mohammad; Balasubramaniam, R.; Nahra, Henry; Mackey, Jeff; Hall, Nancy; Frankenfield, Bruce; Harpster, George; May, Rochelle; Mudawar, Issam; Kharangate, Chirag R.; hide

    2016-01-01

    A ground-based experimental facility to perform flow boiling and condensation experiments is built in support of the development of the long duration Flow Boiling and Condensation Experiment (FBCE) destined for operation on board of the International Space Station (ISS) Fluid Integrated Rack (FIR). We performed tests with the condensation test module oriented horizontally and vertically. Using FC-72 as the test fluid and water as the cooling fluid, we evaluated the operational characteristics of the condensation module and generated ground based data encompassing the range of parameters of interest to the condensation experiment to be performed on the ISS. During this testing, we also evaluated the pressure drop profile across different components of the fluid subsystem, heater performance, on-orbit degassing subsystem, and the heat loss from different components. In this presentation, we discuss representative results of performance testing of the FBCE flow loop. These results will be used in the refinement of the flight system design and build-up of the FBCE which is scheduled for flight in 2019.

  11. Topflow-experiments on direct condensation and bubble entrainment. Technical report

    International Nuclear Information System (INIS)

    Seidel, Tobias; Lucas, Dirk; Beyer, Matthias

    2016-01-01

    Direct Contact Condensation between steam and water as well as bubble entrainment below the water surface play an important role in different accident scenarios for light water reactors. One example is the emergency core cooling water injection into a two-phase mixture. It has to be considered for example to evaluate potential pressurized thermal shock phenomena. This report documents experiments conducted in flat basin inside the TOPFLOW pressure chamber aiming on the generation of a database useful for CFD model development and validation. It comprises 3 different setups: condensation at a stratified flow of sub-cooled water, condensation at a sub-cooled water jet and a combination of both phenomena with steam bubble entrainment. The documentation includes all details on the experimental set up, on experimental conditions (experimental matrices), on the conduction of the experiments, on measuring techniques used and on data evaluation procedures. In addition, selected results are presented.

  12. [X-ray diffraction experiments with condenser matter

    International Nuclear Information System (INIS)

    Coppens, P.

    1990-01-01

    This report discusses research on the following topics: high-T c superconductors; The response of crystal to an applied electric field; quasicrystals; surface structure and kinetics of surface layer formation; EXAFS studies of superconductors and heterostructures; effect of iron on the crystal structure of perovskite; x-ray detector development; and SAXS experiments

  13. Code-experiment comparison on wall condensation tests in the presence of non-condensable gases-Numerical calculations for containment studies

    Energy Technology Data Exchange (ETDEWEB)

    Malet, J., E-mail: jeanne.malet@irsn.fr [Institut de Radioprotection et de Surete Nucleaire (IRSN), PSN-RES, SCA, BP 68, 91192 Gif-sur-Yvette (France); Porcheron, E.; Dumay, F.; Vendel, J. [Institut de Radioprotection et de Surete Nucleaire (IRSN), PSN-RES, SCA, BP 68, 91192 Gif-sur-Yvette (France)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Steam condensation on walls has been investigated in the TOSQAN vessel. Black-Right-Pointing-Pointer Experiments on 7 different tests have been performed. Black-Right-Pointing-Pointer Different steam injections and wall temperatures are used. Black-Right-Pointing-Pointer Simulations are performed in 2D using the TONUS code. Black-Right-Pointing-Pointer Code-experiments comparisons at many different locations show a good agreement. - Abstract: During the course of a severe Pressurized Water Reactor accident, pressurization of the containment occurs and hydrogen can be produced by the reactor core oxidation and distributed in the containment according to convection flows and wall condensation. Filmwise wall condensation in the presence of non-condensable gases is a subject of many interests and extensive studies have been performed in the past. Some empirical correlations have demonstrated their limit for extrapolation under different thermal-hydraulic conditions and at different geometries/scales. The French Institute for Radiological Protection and Nuclear Safety (IRSN) has developed a numerical tool and an experimental facility in order to investigate free convection flows in the presence of condensation. The objective of this paper is to present numerical results obtained on different wall condensation tests in 7 m{sup 3} volume vessel (TOSQAN facility), and to compare them with the experimental ones. Over eight tests are considered here, and code-experiment comparison is performed on many different locations, giving an extensive insight of the code assessment for air-steam mixture flows involving wall condensation in the presence of non-condensable gases.

  14. MELCOR 1.8.1 assessment: PNL Ice Condenser Aerosol Experiments

    International Nuclear Information System (INIS)

    Gross, R.J.

    1993-06-01

    The MELCOR code was used to simulate PNL's Ice Condenser Experiments 11-6 and 16-11. In these experiments, ZnS was injected into a mixing chamber, and the combined steam/air/aerosol mixture flowed into an ice condenser which was l4.7m tall. Experiment 11-6 was a low flow test; Experiment l6-1l was a high flow test. Temperatures in the ice condenser region and particle retention were measured in these tests. MELCOR predictions compared very well to the experimental data. The MELCOR calculations were also compared to CONTAIN code calculations for the same tests. A number of sensitivity studies were performed. It as found that simulation time step, aerosol parameters such as the number of MAEROS components and sections used and the particle density, and ice condenser parameters such as the energy capacity of the ice, ice heat transfer coefficient multiplier, and ice heat structure characteristic length all could affect the results. Thermal/hydraulic parameters such as control volume equilibrium assumptions, flow loss coefficients, and the bubble rise model were found to affect the results less significantly. MELCOR results were not machine dependent for this problem

  15. Preliminary Analysis of Rapid Condensation Experiment with MARS-KS Code

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Ho; Jun, Hwang Yong; Jeong, Hae Yong [Sejong University, Seoul (Korea, Republic of)

    2016-05-15

    In the present study, the rapid condensation experiment performed in MANOTEA facility is analyzed with the MARS-KS code. It is known that there exists some limitation with a system code to predict this kind of a very active condensation due to direct mixing of cold injection flow and steam. Through the analysis we investigated the applicability of MARS-KS code for the design of various passive safety systems in the future. The configuration of the experimental facility MANOTEA, which has been constructed at the University of Maryland - United States Naval Academy, is described and the modeling approach using the MARS-KS code is also provided. The preliminary result shows that the MARS-KS predicts the general trend of pressure and temperature in the condensing part correctly. However, it is also found that there exist some limitations in the simulation such as an unexpected pressure peak or a sudden temperature change.

  16. Simulation of the condensation experiment for the SG primary of SMART with MIDAS/SMR

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Hwa; Kim, Dong Ha; Chung, Young Jong; Park, Sun Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Cho, Seong Won [Korea Radiation Technology Institute Co., Daejeon (Korea, Republic of)

    2012-05-15

    SMART is new concept of reactor that all the main components such as the steam generator, the coolant pumps and the pressurizer are located inside the reactor vessel. MIDAS/SMR V1.0.3 code has been used for estimating the severe accident from SMART. SMART has the SG tube with helical shape that is different from that of PWR. MIDAS code has the condensation model for the both sides of surfaces from the various kinds of geometry. But it does not have the condensation model for the helical type of tube. In this study, the condensation experiment for the outer surface of the SG tube in SMART that was performed by Po-Hang university was simulated with MIDAS/SMR under the assumption of straight pipe. The simulation results showed well predictions of the amount of heat removal from the SG tube primary side and thermal hydraulic parameters

  17. Simulation of the condensation experiment for the SG primary of SMART with MIDAS/SMR

    International Nuclear Information System (INIS)

    Park, Jong Hwa; Kim, Dong Ha; Chung, Young Jong; Park, Sun Hee; Cho, Seong Won

    2012-01-01

    SMART is new concept of reactor that all the main components such as the steam generator, the coolant pumps and the pressurizer are located inside the reactor vessel. MIDAS/SMR V1.0.3 code has been used for estimating the severe accident from SMART. SMART has the SG tube with helical shape that is different from that of PWR. MIDAS code has the condensation model for the both sides of surfaces from the various kinds of geometry. But it does not have the condensation model for the helical type of tube. In this study, the condensation experiment for the outer surface of the SG tube in SMART that was performed by Po-Hang university was simulated with MIDAS/SMR under the assumption of straight pipe. The simulation results showed well predictions of the amount of heat removal from the SG tube primary side and thermal hydraulic parameters

  18. Preliminary condensation pool experiments with steam using DN80 and DN100 blowdown pipes

    International Nuclear Information System (INIS)

    Laine, J.; Puustinen, M.

    2004-03-01

    The report summarizes the results of the preliminary steam blowdown experiments. Altogether eight experiment series, each consisting of several steam blows, were carried out in autumn 2003 with a scaled-down condensation pool test rig designed and constructed at Lappeenranta University of Technology. The main purpose of the experiments was to evaluate the capabilities of the test rig and the needs for measurement and visualization devices. The experiments showed that a high-speed video camera is essential for visual observation due to the rapid condensation of steam bubbles. Furthermore, the maximum measurement frequency of the current combination of instrumentation and data acquisition system is inadequate for the actual steam tests in 2004. (au)

  19. Evolution of the feedback from experience on degradations of French nuclear power plants condensers and foreseen solutions

    Energy Technology Data Exchange (ETDEWEB)

    Mayos, M.; Chanel, F.; Copin, E.; Carlier, L. [EDF/DIN/CEIDRE, Saint-Denis (France); Coquio, N.; Garbay, E. [EDF/DIN/CEIDRE, Avoine (France); Bastian, C. [EDF/DPN/UNIE, Saint-Denis (France)

    2011-07-01

    The materials constituting the condenser tubes of French nuclear power plants display a great diversity and are subject to different degradations, known from the operational feedback from experience. Copper alloys (mainly brass), which were bound to disappear in renovated condensers, are still significantly present, due to their unique bacteriostatic ability. Brass tubes lifetime is still governed in general by steady abrasion, as evaluated by eddy current nondestructive testing. However, an atypical NDE (non-destructive evaluation) behavior has led to spot a new damage: localized under-deposit pitting corrosion on the raw water side, caused by the particular quality of water chemistry and heavy scaling of the tube surface. This damage is likely to overcome steady abrasion for tube life prediction. Prevention includes a tighter look at NDE indications and improved descaling solutions (chemical or mechanical). Other specific damages have been reported from operation feedback: the main one was accidental stress corrosion cracking, which has occurred on some recently renovated brass condenser tube bundles. Thanks to a metallurgical and mechanical study, its cause was found in the manufacturing process. This experience has resulted in tightened specifications for brass tubes manufacturing. Stainless steel and titanium still appear more damage-resistant and represent a safe solution when no microorganism issue is present. The degradation feedback, confirmed by NDE inspections, is very low in French power plants. However, titanium hydriding still represents an issue when cathodic protection is present. Furthermore, some other damages have been reported on titanium, like isolated steam erosion. Vibration fatigue damage has been observed on stainless steel tubes, but it is more in relationship with the condenser design than with the material itself. (authors)

  20. A condensation experiment in the accumulated conditions of noncondensable gas in a vertical tube

    International Nuclear Information System (INIS)

    Lee, Kwon Yeong; Kim, Moo Hwan

    2005-01-01

    Full text of publication follows: It has been well known that the presence of noncondensable gases in vapors can greatly inhibit the condensation process. Many analytical and experimental studies were conducted to investigate the effect of noncondensable gases on steam condensation for both stagnant and forced-convective situations either over a plate or outside a horizontal tube. Recently, several researches have been performed for the condensation in the presence of noncondensable gases taken place inside the vertical tube in order to give the information to design the passive containment cooling system (PCCS) in Simplified Boiling Water Reactor (SBWR). Generally, the experimental results showed that the heat transfer coefficient depends on inlet noncondensable gas mass fraction, inlet saturated steam temperature related with system pressure and inlet mixture Reynolds number. This research was performed for the System-integrated Modular Advanced ReacTor-Pilot (SMART-P), in which the remaining heat is removed from the core passively by Passive Residual Heat Removal System (PRHRS) condenser in a period of serious accident. The PRHRS is separated from working fluid loop, and pressurized by a nitrogen gas during the normal operation of SMART-P. But when the PRHRS starts operating, the nitrogen gas acts as a noncondensable gas and affects the heat transfer characteristics of the PRHRS. The experimental conditions of this study were almost similar with those of previous researches except the noncondensable gas was accumulated and remained inside the vertical tube. In the previous researches, the noncondensable gas was flowing with constant flow rate. Because of the condensate inside condenser tube, the accumulation of noncondensable gas could be developed inside the vertical tube. At steady-state condition the local temperatures and system pressure were measured to obtain heat transfer characteristics. This study also gave the information about the distribution of the

  1. MELCOR simulation of steam condensation effect on hydrogen behavior in THAI HM-2 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seongnyeon; Lee, Jung-Jae; Cho, Yong-Jin [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Kim, Sung Joong [Hanyang University, Seoul (Korea, Republic of)

    2015-10-15

    In this study, MELCOR simulation was carried out for THAI HM-2 experiment of OECD. As a results, stratification of hydrogen cloud was reasonably captured in MELCOR simulation. Furthermore, the pressure from simulation results in cases where mass transfer coefficient of MELCOR condensation model was modified was good agreement with the experimental results. Containment Filtered Ventilation System (CFVS) has been introduced as facility to prevent containment failure during severe accident. However, possibility of hydrogen risk has been issued due to inflow of hydrogen, condensation and removal of steam and complicated inner structure in CFVS. Preferentially benchmark work for THAI HM-2 experiment of OECD was decided to validate the methodology before detailed assessment of hydrogen risk in CFVS. The objectives of THAI HM-2 experiment were evaluation of hydrogen behavior, verification of numerical analysis tools and so on. In this paper, therefore, MELCOR simulation was carried out in comparison with the experiment results. Additionally, steam condensation effect was considered for detailed simulation. Hydrogen concentration from MELCOR results was underestimated in comparison to the experimental results.

  2. Experiments of condensation-induced water hammers at the UniBw Munich

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas

    2013-01-01

    Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

  3. Experiments of condensation-induced water hammers at the UniBw Munich

    Energy Technology Data Exchange (ETDEWEB)

    Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas [Universitaet der Bundeswehr Muenchen, Neubiberg (Germany). Hydromechanik und Wasserbau

    2013-03-15

    Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

  4. Turning Local Bilingualism into a Touristic Experience

    Science.gov (United States)

    Schedel, Larissa Semiramis

    2018-01-01

    Local languages/varieties play a key role in the construction of an authentic and local tourism experience. This is also the case in the bilingual town of Murten, which uses its situation at the language border between the French- and the German-speaking part of Switzerland and the local bilingualism to attract and entertain tourists in different…

  5. MARS-KS Code Assessment for Condensation Heat Transfer in Horizontal Tube with the Presence of Non-Condensable Gas using Purdue Experiment

    International Nuclear Information System (INIS)

    Jeon, Seong Su; Lee, Byung Chul; Park, Ju Yeop; Seul, Kwang Won

    2011-01-01

    uncertainty bounds, the assessment of the model should be provided by comparison with experimental data. In this study, the condensation experiment performed in Purdue University, which was selected as a first validation experiment, was simulated by using MARSKS. By comparing MARS-KS predictions with the experimental data, the accuracy and applicability was investigated

  6. Flow Boiling and Condensation Experiment (FBCE) for the International Space Station

    Science.gov (United States)

    Mudawar, Issam; O'Neill, Lucas; Hasan, Mohammad; Nahra, Henry; Hall, Nancy; Balasubramaniam, R.; Mackey, Jeffrey

    2016-01-01

    An effective means to reducing the size and weight of future space vehicles is to replace present mostly single-phase thermal management systems with two-phase counterparts. By capitalizing upon both latent and sensible heat of the coolant rather than sensible heat alone, two-phase thermal management systems can yield orders of magnitude enhancement in flow boiling and condensation heat transfer coefficients. Because the understanding of the influence of microgravity on two-phase flow and heat transfer is quite limited, there is an urgent need for a new experimental microgravity facility to enable investigators to perform long-duration flow boiling and condensation experiments in pursuit of reliable databases, correlations and models. This presentation will discuss recent progress in the development of the Flow Boiling and Condensation Experiment (FBCE) for the International Space Station (ISS) in collaboration between Purdue University and NASA Glenn Research Center. Emphasis will be placed on the design of the flow boiling module and on new flow boiling data that were measured in parabolic flight, along with extensive flow visualization of interfacial features at heat fluxes up to critical heat flux (CHF). Also discussed a theoretical model that will be shown to predict CHF with high accuracy.

  7. Bose-Einstein condensate collapse: A comparison between theory and experiment

    International Nuclear Information System (INIS)

    Savage, C.M.; Robins, N.P.; Hope, J.J.

    2003-01-01

    We solve the Gross-Pitaevskii equation numerically for the collapse induced by a switch from positive to negative scattering lengths. We compare our results with experiments performed with Bose-Einstein condensates of 85 Rb, in which the scattering length was controlled using a Feshbach resonance. Building on previous theoretical work we identify quantitative differences between the predictions of mean-field theory and the results of the experiments. In addition to the previously reported difference between the predicted and observed critical atom number for collapse, we also find that the predicted collapse times systematically exceed those observed experimentally

  8. Effect of interactions on the localization of a Bose-Einstein condensate in a quasi-periodic lattice

    OpenAIRE

    Lye, J. E.; Fallani, L.; Fort, C.; Guarrera, V.; Modugno, M.; Wiersma, D. S.; Inguscio, M.

    2006-01-01

    The transport properties of a Bose-Einstein condensate in a 1D incommensurate bichromatic lattice are investigated both theoretically and experimentally. We observe a blockage of the center of mass motion with low atom number, and a return of motion when the atom number is increased. Solutions of the Gross-Pitaevskii equation show how the localization due to the quasi-disorder introduced by the incommensurate bichromatic lattice is affected by the interactions.

  9. Direct-contact condensers for open-cycle OTEC applications: Model validation with fresh water experiments for structured packings

    Energy Technology Data Exchange (ETDEWEB)

    Bharathan, D.; Parsons, B.K.; Althof, J.A.

    1988-10-01

    The objective of the reported work was to develop analytical methods for evaluating the design and performance of advanced high-performance heat exchangers for use in open-cycle thermal energy conversion (OC-OTEC) systems. This report describes the progress made on validating a one-dimensional, steady-state analytical computer of fresh water experiments. The condenser model represents the state of the art in direct-contact heat exchange for condensation for OC-OTEC applications. This is expected to provide a basis for optimizing OC-OTEC plant configurations. Using the model, we examined two condenser geometries, a cocurrent and a countercurrent configuration. This report provides detailed validation results for important condenser parameters for cocurrent and countercurrent flows. Based on the comparisons and uncertainty overlap between the experimental data and predictions, the model is shown to predict critical condenser performance parameters with an uncertainty acceptable for general engineering design and performance evaluations. 33 refs., 69 figs., 38 tabs.

  10. The Mott localization and magnetic properties in condensed fermions systems; Lokalizacja Motta i wlasnosci magnetyczne skondensowanych ukladow fermionowych

    Energy Technology Data Exchange (ETDEWEB)

    Wojcik, W. [Politechnika Krakowska, Cracow (Poland)

    1995-12-31

    In the present thesis the Mott localization and magnetic properties in condensed fermions system are considered. The Hubbard model has been used to strongly correlated electron systems and the Skyrme potential to a dense neutron matter with small concentration of protons. A variational approach to the metal-insulator transition is proposed which combines the Mott and Gutzwiller-Brinkman-Rice aspects of the localization. Magnetic properties of strongly correlated electrons are analyzed within the modified spin-rotation-invariant approach in the slow-boson representation. The theoretical prediction for considered systems are presented. 112 refs, 39 figs.

  11. The Mott localization and magnetic properties in condensed fermions systems; Lokalizacja Motta i wlasnosci magnetyczne skondensowanych ukladow fermionowych

    Energy Technology Data Exchange (ETDEWEB)

    Wojcik, W [Politechnika Krakowska, Cracow (Poland)

    1996-12-31

    In the present thesis the Mott localization and magnetic properties in condensed fermions system are considered. The Hubbard model has been used to strongly correlated electron systems and the Skyrme potential to a dense neutron matter with small concentration of protons. A variational approach to the metal-insulator transition is proposed which combines the Mott and Gutzwiller-Brinkman-Rice aspects of the localization. Magnetic properties of strongly correlated electrons are analyzed within the modified spin-rotation-invariant approach in the slow-boson representation. The theoretical prediction for considered systems are presented. 112 refs, 39 figs.

  12. Thermal hydraulics-I. 5. Local Heat Transfer and Flow Transition in U-Tubes During a Reflux Condensation Mode

    International Nuclear Information System (INIS)

    Chun, Moon-Hyun; Lee, Kyung-Won; Chu, In-Cheol

    2001-01-01

    For the safety analysis of nuclear power plant (NPP) mid-loop operation, it is very important to determine the mechanisms governing heat transfer and to investigate the factors affecting the onset of flooding in steam generator U-tubes during a reflux condensation mode. The main purpose of this work is to evaluate the local condensation heat transfer with and without non-condensable gases (air) and to investigate the effect of multiple U-tubes on the onset of flooding during a reflux condensation. A schematic diagram of the experimental apparatus is shown in Fig. 1. In the present study, five U-tubes with the same inner diameter of 0.0162 m are installed in a rectangular pool to simulate the geometry of the pressurized water reactor steam generator U-tubes of the Korea standard NPP (KSNPP) (Ulchin Units 3 and 4, inner diameter≅0.01692 m). One central U-tube (2.8 m high) is fully equipped with 32 thermocouples to evaluate the heat transfer coefficients (HTCs), whereas the others (i.e., two short tubes 2.5 m high and two long tubes 3.3 m high) are used to investigate the effect of multiple U-tubes on the flooding phenomena. The local heat flux through a U-tube wall was evaluated from the temperature gradient of the U-tube wall. The onset of flooding, on the other hand, was determined by measuring the change in pressure difference between the bottom and the top of the U-tubes. A total of 512 data for local condensation HTCs (108 for pure steam flow and 404 for steam-air flow conditions, respectively) have been obtained for various flow rates of steam and air under atmospheric conditions. The experimental results for a pure steam flow, in general, agree with the classical Nusselt theory, as shown in Fig. 2. At a relatively high-steam Reynolds number (i.e., >3500), however, the present data are slightly higher than the values predicted by Nusselt theory because of the influence of interfacial shear. In the case of pure steam condensation, the condensate film acts as

  13. Cooperative and Heterogeneous Indoor Localization - Experiments

    DEFF Research Database (Denmark)

    Benoît, Denis; Raulefs, Ronald; Fleury, Bernard Henri

    2013-01-01

    In this paper we present the results of real-life localization experiments performed in an unprecedented cooperative and heterogeneous wireless context. These measurements are based on ZigBee and orthogonal frequency division multiplexing (OFDM) devices, respectively endowed with received signal...

  14. Experiments on condensation heat transfer characteristics inside a microfin tube with R410A

    Energy Technology Data Exchange (ETDEWEB)

    Han, D H; Cho, Y J [Korea University Graduate School, Seoul (Korea); Lee, K J; Park, S S [Korea University, Seoul (Korea)

    2000-11-01

    Due to the ozone depletion and global warming potentials, some refrigerants (CFCs and HCFCs) have been rapidly substituted. R410A is considered as the alternative refrigerant of R22 for the air-conditioners used at home and in industry. Experiments on the condensation heat transfer characteristics inside a smooth or a micro-fin tube with R410A are performed in this study. The test tubes 7/9.52 mm in outer diameters and 3 m in length are used. Varying the mass flux of the refrigerant and the condensation temperatures, the average heat transfer coefficients and pressure drop are investigated. It is shown that the heat transfer is enhanced and the amount of pressure drops are larger in the microfin tube than the smooth tube. From the heat transfer enhancement coefficient and the pressure penalty factor, it is found that the high heat transfer enhancement coefficients are obtained in the range of small mass flux while the penalty factors are almost equal. (author). 13 refs., 12 figs., 1 tab.

  15. Single-tube condensation experiment in Passive Auxiliary Feedwater System of APR1400+

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chang Wook; No, Hee Cheon; Yun, Bong Yo; Jeon, Byong Guk [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2012-05-15

    Conventional Korean nuclear power plants, Advanced Power Reactors (APR), are characterized by an active cooling system. However, Active cooling system may not prevent significant damage without any AC power source available for its operation as vividly illustrated through the recent Fukushima incident. In the APR1400+ to be designed, an independent passive cooling system was added in order to overcome the aforementioned shortcomings. In the Passive Auxiliary Feedwater System (PAFS), gravity force and density difference between steam and water are used. The system comprises of 240 condensation tubes to efficiently remove decay heat. Before applying the PAFS to APR1400+, the system's safety and heat removal performance must be verified. The present study experimentally evaluates the heat removal performance of a single tube in the PAFS. The objectives of SCOP (Single-tube Condensation experiment facility of PAFS) are the evaluation of the heat removal performance in the tube of the PAFS and database construction under various tube designs and test conditions. Reaching these objectives, we developed advanced measurement techniques for the amount of moisture, heat flux, and water film thickness.

  16. Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

    Energy Technology Data Exchange (ETDEWEB)

    Dirndorfer, Stefan

    2017-01-17

    Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

  17. Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan

    2017-01-01

    Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

  18. Casimir amplitudes and capillary condensation of near-critical fluids between parallel plates: renormalized local functional theory.

    Science.gov (United States)

    Okamoto, Ryuichi; Onuki, Akira

    2012-03-21

    We investigate the critical behavior of a near-critical fluid confined between two parallel plates in contact with a reservoir by calculating the order parameter profile and the Casimir amplitudes (for the force density and for the grand potential). Our results are applicable to one-component fluids and binary mixtures. We assume that the walls absorb one of the fluid components selectively for binary mixtures. We propose a renormalized local functional theory accounting for the fluctuation effects. Analysis is performed in the plane of the temperature T and the order parameter in the reservoir ψ(∞). Our theory is universal if the physical quantities are scaled appropriately. If the component favored by the walls is slightly poor in the reservoir, there appears a line of first-order phase transition of capillary condensation outside the bulk coexistence curve. The excess adsorption changes discontinuously between condensed and noncondensed states at the transition. With increasing T, the transition line ends at a capillary critical point T=T(c) (ca) slightly lower than the bulk critical temperature T(c) for the upper critical solution temperature. The Casimir amplitudes are larger than their critical point values by 10-100 times at off-critical compositions near the capillary condensation line. © 2012 American Institute of Physics

  19. Interstellar silicate analogs for grain-surface reaction experiments: Gas-phase condensation and characterization of the silicate dust grains

    Energy Technology Data Exchange (ETDEWEB)

    Sabri, T.; Jäger, C. [Laboratory Astrophysics Group of the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena Institute of Solid State Physics, Helmholtzweg 3, D-07743 Jena (Germany); Gavilan, L.; Lemaire, J. L.; Vidali, G. [Observatoire de Paris/Université de Cergy-Pontoise, 5 mail Gay Lussac, F-95000 Cergy-Pontoise (France); Mutschke, H. [Laboratory Astrophysics Group of the Astrophysical Institute and University Observatory, Friedrich Schiller University Jena Schillergässchen 3, D-07743 Jena (Germany); Henning, T., E-mail: tolou.sabri@uni-jena.de [Max Planck Institute for Astronomy Königstuhl 17, D-69117 Heidelberg (Germany)

    2014-01-10

    Amorphous, astrophysically relevant silicates were prepared by laser ablation of siliceous targets and subsequent quenching of the evaporated atoms and clusters in a helium/oxygen gas atmosphere. The described gas-phase condensation method can be used to synthesize homogeneous and astrophysically relevant silicates with different compositions ranging from nonstoichiometric magnesium iron silicates to pyroxene- and olivine-type stoichiometry. Analytical tools have been used to characterize the morphology, composition, and spectral properties of the condensates. The nanometer-sized silicate condensates represent a new family of cosmic dust analogs that can generally be used for laboratory studies of cosmic processes related to condensation, processing, and destruction of cosmic dust in different astrophysical environments. The well-characterized silicates comprising amorphous Mg{sub 2}SiO{sub 4} and Fe{sub 2}SiO{sub 4}, as well as the corresponding crystalline silicates forsterite and fayalite, produced by thermal annealing of the amorphous condensates, have been used as real grain surfaces for H{sub 2} formation experiments. A specifically developed ultra-high vacuum apparatus has been used for the investigation of molecule formation experiments. The results of these molecular formation experiments on differently structured Mg{sub 2}SiO{sub 4} and Fe{sub 2}SiO{sub 4} described in this paper will be the topic of the next paper of this series.

  20. Local island divertor experiments on LHD

    International Nuclear Information System (INIS)

    Morisaki, T.; Masuzaki, S.; Komori, A.; Ohyabu, N.; Kobayashi, M.; Feng, Y.; Sardei, F.; Narihara, K.; Tanaka, K.; Ida, K.; Peterson, B.J.; Yoshinuma, M.; Ashikawa, N.; Emoto, M.; Funaba, H.; Goto, M.; Ikeda, K.; Inagaki, S.; Kaneko, O.; Kawahata, K.; Kubo, S.; Miyazawa, J.; Morita, S.; Nagaoka, K.; Nagayama, Y.; Nakanishi, H.; Ohkubo, K.; Oka, Y.; Osakabe, M.; Shimozuma, T.; Shoji, M.; Takeiri, Y.; Sakakibara, S.; Sakamoto, R.; Sato, K.; Toi, K.; Tsumori, K.; Watababe, K.Y.; Yamada, H.; Yamada, I.; Yoshimura, Y.; Motojima, O.

    2005-01-01

    A local island divertor (LID) experiment has begun on LHD, with the aims of controlling edge recycling and improving the plasma confinement. The fundamental divertor functions of the LID have been demonstrated in the recent experiments. From the particle flux profile measurements on the LID head it was found that the particles diffusing out from the core region are well guided along the island separatrix to the LID head. Owing to the closed configuration around the LID head, evidence of the high efficient pumping was observed, together with a strong capacity to screen impurities. The first results of edge modeling using the EMC3-EIRENE code are also presented

  1. Investigation and mitigation of condensation induced water hammer by stratified flow experiments

    Science.gov (United States)

    Kadakia, Hiral J.

    This research primarily focuses on the possibility of using stratified flow in preventing an occurrence of condensation induced water hammer (CIWH) in horizontal pipe involving steam and subcooled water. A two-phase flow loop simulating the passive safety systems of an advanced light water reactor was constructed and a series of stratified flow experiments were carried out involving a system of subcooled water, saturated water, and steam. Special instruments were designed to measure steam flow rate and subcooled liquid velocity. These experiments showed that when flow field conditions meet certain criteria CIWH does occur. Flow conditions used in experiments were typically observed in passive safety systems of an advanced light water cooled reactor. This research summarizes a) literature research and other experimental data that signify an occurrence of CIWH, b) experiments in an effort to show an occurrence of CIWH and the ability to prevent CIWH, c) qualitative and quantitative results to underline the mechanism of CIWH, d) experiments that show CIWH can be prevented under certain conditions, and e) guidelines for the safe operating conditions. Based on initial experiment results it was observed that Bernoulli's effect can play an important role in wave formation and instability. A separate effect table top experiment was constructed with plexi-glass. A series of entrance effect tests and stratified experiments were carried out with different fluids to study wave formation and wave bridging. Special test series experiments were carried out to investigate the presence of a saturated layer. The effect of subcooled water and steam flow on wedge length and depth were recorded. These experiments helped create a model which calculates wedge and depth of wedge for a given condition of steam and subcooled water. A very good comparison between the experiment results and the model was obtained. These experiments also showed that the presence of saturated layer can mitigate

  2. Design and performance evaluation of a cryogenic condenser for an in-pile experiment

    Science.gov (United States)

    Graham, R. W.; Crum, R. J.; Hsu, Y.

    1972-01-01

    An apparatus was designed to enable in-pile irradiation of materials in liquid hydrogen at cryogenic temperatures. One of the principal components of this apparatus was a horizontal tube condenser. The performance of the condenser was evaluated by running a liquid-nitrogen prototype of the apparatus at heat loads comparable to or greater than those expected during the irradiation. The test showed that the condenser was capable of handling the design heat load and that the design procedure was sound.

  3. Quantum localization and bound-state formation in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Franzosi, Roberto; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2010-01-01

    We discuss the possibility of exponential quantum localization in systems of ultracold bosonic atoms with repulsive interactions in open optical lattices without disorder. We show that exponential localization occurs in the maximally excited state of the lowest energy band. We establish the conditions under which the presence of the upper energy bands can be neglected, determine the successive stages and the quantum phase boundaries at which localization occurs, and discuss schemes to detect it experimentally by visibility measurements. The discussed mechanism is a particular type of quantum localization that is intuitively understood in terms of the interplay between nonlinearity and a bounded energy spectrum.

  4. Development of Flow Boiling and Condensation Experiment on the International Space Station- Normal and Low Gravity Flow Boiling Experiment Development and Test Results

    Science.gov (United States)

    Nahra, Henry K.; Hall, Nancy R.; Hasan, Mohammad M.; Wagner, James D.; May, Rochelle L.; Mackey, Jeffrey R.; Kolacz, John S.; Butcher, Robert L.; Frankenfield, Bruce J.; Mudawar, Issam; hide

    2013-01-01

    Flow boiling and condensation have been identified as two key mechanisms for heat transport that are vital for achieving weight and volume reduction as well as performance enhancement in future space systems. Since inertia driven flows are demanding on power usage, lower flows are desirable. However, in microgravity, lower flows are dominated by forces other than inertia (like the capillary force). It is of paramount interest to investigate limits of low flows beyond which the flow is inertial enough to be gravity independent. One of the objectives of the Flow Boiling and Condensation Flight Experiment sets to investigate these limits for flow boiling and condensation. A two-phase flow loop consisting of a Flow Boiling Module and two Condensation Modules has been developed to experimentally study flow boiling condensation heat transfer in the reduced gravity environment provided by the reduced gravity platform. This effort supports the development of a flow boiling and condensation facility for the International Space Station (ISS). The closed loop test facility is designed to deliver the test fluid, FC-72 to the inlet of any one of the test modules at specified thermodynamic and flow conditions. The zero-g-aircraft tests will provide subcooled and saturated flow boiling critical heat flux and flow condensation heat transfer data over wide range of flow velocities. Additionally, these tests will verify the performance of all gravity sensitive components, such as evaporator, condenser and accumulator associated with the two-phase flow loop. We will present in this paper the breadboard development and testing results which consist of detailed performance evaluation of the heater and condenser combination in reduced and normal gravity. We will also present the design of the reduced gravity aircraft rack and the results of the ground flow boiling heat transfer testing performed with the Flow Boiling Module that is designed to investigate flow boiling heat transfer and

  5. Collection of european experiences in local investment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This booklet is realized within the framework of the european project called PREDAC. This objective of this project are to promote citizen participation in the financing of renewable energies projects in Europe, to make organizations, investor clubs and local government to be aware of this way of implication into renewable energies development. The first part presents a collection of european experiences, as discussions and perspectives are proposed in the second part. The last part gives a comparative table between Germany and Denmark in term of renewable energies development. (A.L.B.)

  6. Assessment of RELAP5/MOD3.2 with condensation experiment in the presence of noncondensables in a vertical tube

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun Sik; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1999-12-31

    The standard RELAP5/MOD3.2 code were assessed with the condensation experiment in the presence of noncondensable gas in a vertical tube of PCCS of CP-1300. There are two wall film condensation models, the default model and the alternative model, in RELAP5/MOD3.2. The experimental apparatus was modeled with the two models, and simulations were performed for several sub-tests to be compared with the experimental results. In overall sense the simulation results showed that the default model of RELAP5/MOD3.2 under-predicts the heat transfer coefficients, while the alternative model over-predicts them throughout the condensing tube. 10 refs., 6 figs. (Author)

  7. Assessment of RELAP5/MOD3.2 with condensation experiment in the presence of noncondensables in a vertical tube

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun Sik; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    The standard RELAP5/MOD3.2 code were assessed with the condensation experiment in the presence of noncondensable gas in a vertical tube of PCCS of CP-1300. There are two wall film condensation models, the default model and the alternative model, in RELAP5/MOD3.2. The experimental apparatus was modeled with the two models, and simulations were performed for several sub-tests to be compared with the experimental results. In overall sense the simulation results showed that the default model of RELAP5/MOD3.2 under-predicts the heat transfer coefficients, while the alternative model over-predicts them throughout the condensing tube. 10 refs., 6 figs. (Author)

  8. Preliminary condensation pool experiments with steam using DN80 and DN100 blowdown pipes[VIDEO CAMERAS

    Energy Technology Data Exchange (ETDEWEB)

    Laine, J.; Puustinen, M. [Lappeenranta University of Technology (Finland)

    2004-03-01

    The report summarizes the results of the preliminary steam blowdown experiments. Altogether eight experiment series, each consisting of several steam blows, were carried out in autumn 2003 with a scaled-down condensation pool test rig designed and constructed at Lappeenranta University of Technology. The main purpose of the experiments was to evaluate the capabilities of the test rig and the needs for measurement and visualization devices. The experiments showed that a high-speed video camera is essential for visual observation due to the rapid condensation of steam bubbles. Furthermore, the maximum measurement frequency of the current combination of instrumentation and data acquisition system is inadequate for the actual steam tests in 2004. (au)

  9. Mixed-symmetry localized modes and breathers in binary mixtures of Bose-Einstein condensates in optical lattices

    International Nuclear Information System (INIS)

    Cruz, H. A.; Brazhnyi, V. A.; Konotop, V. V.; Alfimov, G. L.; Salerno, M.

    2007-01-01

    We study localized modes in binary mixtures of Bose-Einstein condensates embedded in one-dimensional optical lattices. We report a diversity of asymmetric modes and investigate their dynamics. We concentrate on the cases where one of the components is dominant, i.e., has a much larger number of atoms than the other one, and where both components have the numbers of atoms of the same order but different symmetries. In the first case we propose a method of systematically obtaining the modes, considering the ''small'' component as bifurcating from the continuum spectrum. A generalization of this approach combined with the use of the symmetry of the coupled Gross-Pitaevskii equations allows for obtaining breather modes, which are also presented

  10. From capillary condensation to interface localization transitions in colloid-polymer mixtures confined in thin-film geometry.

    Science.gov (United States)

    De Virgiliis, Andres; Vink, Richard L C; Horbach, Jürgen; Binder, Kurt

    2008-10-01

    Monte Carlo simulations of the Asakura-Oosawa model for colloid-polymer mixtures confined between two parallel repulsive structureless walls are presented and analyzed in the light of current theories on capillary condensation and interface localization transitions. Choosing a polymer-to-colloid size ratio of q=0.8 and studying ultrathin films in the range of D=3 to D=10 colloid diameters thickness, grand canonical Monte Carlo methods are used; phase transitions are analyzed via finite size scaling, as in previous work on bulk systems and under confinement between identical types of walls. Unlike the latter work, inequivalent walls are used here: While the left wall has a hard-core repulsion for both polymers and colloids, at the right-hand wall an additional square-well repulsion of variable strength acting only on the colloids is present. We study how the phase separation into colloid-rich and colloid-poor phases occurring already in the bulk is modified by such a confinement. When the asymmetry of the wall-colloid interaction increases, the character of the transition smoothly changes from capillary condensation type to interface localization type. For very thin films (i.e., for D=3 ) and a suitable choice of the wall-colloid interactions, evidence is found that the critical behavior falls in the universality class of the two-dimensional Ising model. Otherwise, we observe crossover scaling between different universality classes (namely, the crossover from the three-dimensional to the two-dimensional Ising model universality class). The colloid and polymer density profiles across the film in the various phases are discussed, as well as the correlation of interfacial fluctuations in the direction parallel to the confining walls. The broadening of the interface between the coexisting colloid-rich and polymer-rich phases (located parallel to the confining walls) is understood in terms of capillary wave fluctuations. The experimental observability of all these

  11. Local diffusion coefficient determination: Mediterranean Sea experiments

    International Nuclear Information System (INIS)

    Bacciola, D.; Borghini, M.; Cannarsa, S.

    1993-10-01

    The Mediterranean is a semi/enclosed basin characterized by the presence of channels and straits influencing the circulation, temperature and salinity fields. The tides generally have amplitudes of the order of 10 cm and velocities of few cm/s. Conversely, the wind forced circulation is very strong and can assume velocity values of 1 m/s at the sea surface. The temperature and salinity fields have a high temporal and spatial variability, because of many mixing processes existing in the sea. For example, the waters coming from the Provencal basin meet those waters coming from the Tyrrhenian Sea in the eastern Ligurian Sea, creating meanders and eddies. Local runoff influences significantly the coastal circulation. This paper describes diffusion experiments carried out in this complex environment. The experimental apparatus for the detection of the fluorescine released at sea was composed by two Turner mod. 450 fluorometres. During the experiments, temperature and salinity vertical profiles were measured by using a CTD; meteorological data were acquired on a dinghy. The positioning was obtained by means of a Motorola system, having a precision of about 1 meter. The experiments were carried out under different stratification and wind conditions. From data analysis it was found that the horizontal diffusion coefficient does not depend on time or boundary conditions. The role of stratification is important with regard to vertical displacement of the dye. However, its role with regard to vertical diffusion cannot be assessed with the actual experimental apparatus

  12. Solitons in quasi-one-dimensional Bose-Einstein condensates with competing dipolar and local interactions

    International Nuclear Information System (INIS)

    Cuevas, J.; Malomed, Boris A.; Kevrekidis, P. G.; Frantzeskakis, D. J.

    2009-01-01

    We study families of one-dimensional matter-wave bright solitons supported by the competition of contact and dipole-dipole (DD) interactions of opposite signs. Soliton families are found, and their stability is investigated in the free space and in the presence of an optical lattice (OL). Free-space solitons may exist with an arbitrarily weak local attraction if the strength of the DD repulsion is fixed. In the case of the DD attraction, solitons do not exist beyond a maximum value of the local-repulsion strength. In the system which includes the OL, a stability region for subfundamental solitons is found in the second finite band gap. For the existence of gap solitons (GSs) under the attractive DD interaction, the contact repulsion must be strong enough. In the opposite case of the DD repulsion, GSs exist if the contact attraction is not too strong. Collisions between solitons in the free space are studied too. In the case of the local attraction, they merge or pass through each other at small and large velocities, respectively. In the presence of the local repulsion, slowly moving solitons bounce from each other.

  13. Nonlinear localized modes in dipolar Bose-Einstein condensates in optical lattices

    International Nuclear Information System (INIS)

    Rojas-Rojas, S.; Vicencio, R. A.; Molina, M. I.; Abdullaev, F. Kh.

    2011-01-01

    Modulational instability and discrete matter wave solitons in dipolar BECs, loaded into a deep optical lattice, are investigated analytically and numerically. The process of modulational instability of nonlinear plane matter waves in a dipolar nonlinear lattice is studied and the regions of instability are established. The existence and stability of bulk discrete solitons are analyzed analytically and confirmed by numerical simulations. In marked contrast with the usual discrete nonlinear Schroedinger behavior (no dipolar interactions), we found a region where the two fundamental modes are simultaneously unstable, allowing enhanced mobility across the lattice for large norm values. To study the existence and properties of surface discrete solitons, an analysis of the dimer configuration is performed. The properties of symmetric and antisymmetric modes including stability diagrams and bifurcations are investigated in closed form. For the case of a bulk medium, properties of fundamental on-site and intersite localized modes are analyzed. On-site and intersite surface localized modes are studied, and we find that they do not exist when nonlocal interactions predominate with respect to local ones.

  14. On the contribution of polycyclic aromatic hydrocarbons to the carcinogenic impact of automobile exhaust condensate evaluated by local application onto mouse skin.

    Science.gov (United States)

    Grimmer, G; Brune, H; Deutsch-Wenzel, R; Naujack, K W; Misfeld, J; Timm, J

    1983-11-01

    The objective of this investigation was to identify the substances chiefly responsible for the carcinogenicity of automobile exhaust condensate using topical application onto the skin of mice. This was performed by comparing the carcinogenic effect of various fractions with that of an unseparated sample of automobile exhaust condensate, tested in 3 different doses. The probit and Weibull analysis of the result shows: (a) The condensate, emitted from a gasoline-driven automobile provokes local tumors after long-term application to the dorsal skin of mice. The tumor incidence demonstrates a clear cut dose-response relationship. (b) The fraction of polycyclic aromatic hydrocarbons (PAH) containing more than 3 rings accounts for about 84-91% of the total carcinogenicity of automobile exhaust condensate. This fraction represents only about 3.5% by wt of the condensate. (c) The content of benzo[a]pyrene (BaP) (0.414 mg/g) accounts for 6-7.6% of the total carcinogenicity of automobile exhaust condensate, 15 selected PAHs for about 41%. (d) Regarding the minor effect of the PAH-free fraction (about 83% by wt), no hints for a cocarcinogenic activity were observed.

  15. Correlation induced localization of lattice trapped bosons coupled to a Bose–Einstein condensate

    Science.gov (United States)

    Keiler, Kevin; Krönke, Sven; Schmelcher, Peter

    2018-03-01

    We investigate the ground state properties of a lattice trapped bosonic system coupled to a Lieb–Liniger type gas. Our main goal is the description and in depth exploration and analysis of the two-species many-body quantum system including all relevant correlations beyond the standard mean-field approach. To achieve this, we use the multi-configuration time-dependent Hartree method for mixtures (ML-MCTDHX). Increasing the lattice depth and the interspecies interaction strength, the wave function undergoes a transition from an uncorrelated to a highly correlated state, which manifests itself in the localization of the lattice atoms in the latter regime. For small interspecies couplings, we identify the process responsible for this cross-over in a single-particle-like picture. Moreover, we give a full characterization of the wave function’s structure in both regimes, using Bloch and Wannier states of the lowest band, and we find an order parameter, which can be exploited as a corresponding experimental signature. To deepen the understanding, we use an effective Hamiltonian approach, which introduces an induced interaction and is valid for small interspecies interaction. We finally compare the ansatz of the effective Hamiltonian with the results of the ML-MCTDHX simulations.

  16. Edge localized modes control: experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Bedoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P. [Association Euratom-CEA, Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Gonsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Burell, H.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A.; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Lonnroth, J.; Kamiya, K.; Shimada, M.; Polevoi, A.; Federici, G

    2004-07-01

    The paper reviews recent theoretical and experimental results focusing on the identification of the key factors controlling ELM (energy localized mode) energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. The theoretical description of the most studied Type-I ELMs is progressing from linear MHD stability analysis for peeling and ballooning modes to the non-linear explosive models and transport codes. Present theories cannot predict the ELM size self-consistently, however they pointed out the benefit of the high plasma shaping, high q{sub 95} and high pedestal density in reducing the ELM affected area. The experimental data also suggest that the conductive energy losses in Type-I ELM can be controlled by working in specific plasma conditions. In particular, the existence of purely convective small Type-I ELMs regimes at high q{sub 95} (>4.5) with {delta}W{sub ELM}/W{sub ped}<5% was demonstrated in high triangularity ({delta} {approx} 0.5) plasmas in JET. Small benign ELMs regimes in present machines (EDA, HRS, Type-II, grassy, QH, Type-III in impurity seeded discharges at high {delta} and their relevance for ITER parameters are reviewed briefly. The absence of already developed ITER relevant high confinement scenarios with acceptable ELMs has motivated recent intensive experimental and theoretical studies of active control of ELMs. The possibility of suppression of Type-I ELMs in H-mode scenarios at constant confinement was demonstrated in DIII-D experiments with a stochastic boundary created by external coils. It has been demonstrated in AUG that small pellets can trigger Type-I ELMs with a frequency imposed by the pellet injector. Pellet induced ELMs are similar to the intrinsic Type-I ELMs with the same frequency. At the same time the confinement degradation due to the fuelling can be minimized with pellets small as compared to the gas injection. Recent plasma current ramp experiments (JET, COMPASS-D) and

  17. Edge localized modes control: experiment and theory

    International Nuclear Information System (INIS)

    Bedoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P.; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Gonsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Burell, H.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A.; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Lonnroth, J.; Kamiya, K.; Shimada, M.; Polevoi, A.; Federici, G.

    2004-01-01

    The paper reviews recent theoretical and experimental results focusing on the identification of the key factors controlling ELM (energy localized mode) energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. The theoretical description of the most studied Type-I ELMs is progressing from linear MHD stability analysis for peeling and ballooning modes to the non-linear explosive models and transport codes. Present theories cannot predict the ELM size self-consistently, however they pointed out the benefit of the high plasma shaping, high q 95 and high pedestal density in reducing the ELM affected area. The experimental data also suggest that the conductive energy losses in Type-I ELM can be controlled by working in specific plasma conditions. In particular, the existence of purely convective small Type-I ELMs regimes at high q 95 (>4.5) with ΔW ELM /W ped <5% was demonstrated in high triangularity (δ ∼ 0.5) plasmas in JET. Small benign ELMs regimes in present machines (EDA, HRS, Type-II, grassy, QH, Type-III in impurity seeded discharges at high δ and their relevance for ITER parameters are reviewed briefly. The absence of already developed ITER relevant high confinement scenarios with acceptable ELMs has motivated recent intensive experimental and theoretical studies of active control of ELMs. The possibility of suppression of Type-I ELMs in H-mode scenarios at constant confinement was demonstrated in DIII-D experiments with a stochastic boundary created by external coils. It has been demonstrated in AUG that small pellets can trigger Type-I ELMs with a frequency imposed by the pellet injector. Pellet induced ELMs are similar to the intrinsic Type-I ELMs with the same frequency. At the same time the confinement degradation due to the fuelling can be minimized with pellets small as compared to the gas injection. Recent plasma current ramp experiments (JET, COMPASS-D) and modelling (JETTO) demonstrated that the edge

  18. Vapor Compression and Thermoelectric Heat Pump Heat Exchangers for a Condensate Distillation System: Design and Experiment

    Science.gov (United States)

    Erickson, Lisa R.; Ungar, Eugene K.

    2013-01-01

    Maximizing the reuse of wastewater while minimizing the use of consumables is critical in long duration space exploration. One of the more promising methods of reclaiming urine is the distillation/condensation process used in the cascade distillation system (CDS). This system accepts a mixture of urine and toxic stabilizing agents, heats it to vaporize the water and condenses and cools the resulting water vapor. The CDS wastewater flow requires heating and its condensate flow requires cooling. Performing the heating and cooling processes separately requires two separate units, each of which would require large amounts of electrical power. By heating the wastewater and cooling the condensate in a single heat pump unit, mass, volume, and power efficiencies can be obtained. The present work describes and compares two competing heat pump methodologies that meet the needs of the CDS: 1) a series of mini compressor vapor compression cycles and 2) a thermoelectric heat exchanger. In the paper, the system level requirements are outlined, the designs of the two heat pumps are described in detail, and the results of heat pump performance tests are provided. A summary is provided of the heat pump mass, volume and power trades and a selection recommendation is made.

  19. Low pressure lithium condensation

    International Nuclear Information System (INIS)

    Wadkins, R.P.; Oh, C.H.

    1985-01-01

    A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

  20. Lesotho's Democratic Local Government Experiment | Lebusa ...

    African Journals Online (AJOL)

    The residues of Lesotho's political past (party politics, inter-party confl ict and conflict over economic resources and their distribution) remain in force within Lesotho's local government process. Despite commitment to decentralise and the promises for enhanced democracy and poverty reduction, the local government ...

  1. Danish Experience in Local Energy Planning

    DEFF Research Database (Denmark)

    Lund, Henrik; Sørensen, Per Alex

    2003-01-01

    The paper describes the influence from public participation brings examples of local energy planning from Ærø and Samsø islands in Denmark.......The paper describes the influence from public participation brings examples of local energy planning from Ærø and Samsø islands in Denmark....

  2. Operational experiences with condensate purifiers at the Paks Nuclear Power Plant, Hungary

    International Nuclear Information System (INIS)

    Doma, Arpad; Patek, Gabor

    1990-01-01

    Increasingly stricter criteria are applied to the secondary cooling circuits of nuclear power stations, due to technology development of feedwater supply systems. Demands for the minimization of ionic impurities caused by leaks and by the corrosion and erosion products from the unstable metal-water thermodynamic system are growing continuously. Therefore, a full-flow condensate purification system has been installed at the PNPP to meet increased water requirements, and its operation is described. (R.P.) 19 figs

  3. Photothermal experiments on condensed phase samples of agricultural interest : optical and thermal characterization

    OpenAIRE

    Favier, J.P.

    1997-01-01


    A rapidly increasing number of photothermal (PT) techniques has had a considerable impact on agriculture and environmental sciences in the last decade. It was the purpose of the work described here to develop and apply new PT techniques in this specific field of research.

    Chapter I is a general introduction with an overview of PT techniques used in this research. Two different photoacoustic (PA) techniques used for optical characterization of a variety of condensed phase sa...

  4. Modelling of local steam condensation on walls in presence of noncondensable gases. Application to a local calculation in reactor containment using the multidimensional geyser code

    International Nuclear Information System (INIS)

    Benet, L.V.; Caroli, C.; Cornet, P.; Coulon, N.; Magnaud, J.P.

    1995-01-01

    The frame of this paper is the study of severe accidents of pressurized water reactors (PWR). The need for containment modelling, and in particular for hydrogen risk study, was reinforced in France after 1990, with the requirement of taking into account severe accidents in design of future plants. This new need of assessing the transient local hydrogen concentration incited us to develop the multidimensional code GEYSER for containment analysis. This code, developed by the Department of Mechanics and Technology of the French Atomic Energy Commission, is presented here with a detailed example of calculation. We describe the mixture, whose constituents are noncondensable gases (air or air and hydrogen) and water vapor liquid, by a compressible homogeneous diphasic model. The wall condensation is based on the Chilton-Colburn formulation and heat mass transfer analogy. We present a transient two-dimensional axisymmetric calculation of a simplified accidental sequence during one hour. The calculation in the large volume of a reactor containment consists of an injection of vapor, first important then moderate, followed by an injection of hydrogen. (authors). 8 refs., 4 figs., 4 tabs

  5. Operating power plant experience with condensate polishing units in morpholine/ammonia-OH cycle

    International Nuclear Information System (INIS)

    Kumbhar, A.G.; Padmakumari, T.V.; Narasimhan, S.V.; Mathur, P.K.

    1995-01-01

    Impurity removal efficiency of condensate polisher plant (CPP) in ammonium cycle is poor. Cost considerations demand CPP operation in amine-OH cycle. With certain precautions such as higher regeneration levels, good regenerent quality, minimized cross contamination, continuous monitoring of influent and effluent and provision for 100% standby bed, it is possible to operate CPP beyond H-OH cycle while keeping the effluent impurities within the specified limits. This paper presents problem associated with the Madras Atomic Power Station (MAPS) CPP operation in morpholine-OH form and Korba Super Thermal Power Station (KSTPS) CPP in ammonia-OH form and suggested remedial measures. (author). 3 refs., 1 fig

  6. Local investment in renewable energies - European experiences

    International Nuclear Information System (INIS)

    Quantin, J.; Grepmeier, K.; Larsen, J.; Manolakaki, E.; Smith, M.

    2004-01-01

    This booklet is realized within the framework of the european commission called PREDAC. This document have been conceived by a working group specialized on the local investment into renewable energies thematic. The objectives of this project are: to promote citizen participation in the financing of renewable energies projects in Europe; to make organizations, investor clubs and local government to be aware of this way of implication into renewable energies development; to examine more especially three renewable energy sources: biomass, photovoltaic and wind in Denmark, France, Germany, Greece and United Kingdom. (author)

  7. Modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Jeong, Jae Jun; Chang, Won Pyo

    1996-07-01

    Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

  8. Current experience and a new modeling on water hammer due to steam condensation in PWR secondary system

    International Nuclear Information System (INIS)

    Kawanishi, K.; Kasahara, J.; Ueno, T.; Suzuta, T.

    1998-01-01

    There have been possibilities to occur water hammer in pipelines of turbine system for nuclear or fossil fuel power plants. According to the NUREG report, approximately 150 events have been reported since 1969, we also have an experience recently. Water hammer occurs due to sudden steam condensation with pressure pulse. This kind of pressure pulses has been made by alternative producing and condensing of steam slug in the pipe and its frequency relates subcooling and pipe structures. This paper presents our current experience on water hammer with some experimental studies. The present experiment has been performed to obtain the data base for evaluating the pressure pulses. The test pipe was horizontal tubes with dead end connected to vertical tube which simulating drain line in PWR secondary system. The main results are shown as follows; Magnitude of pressure pulse depends drain velocity and initial subcooling. Pipe structure effects on the frequency and continual time of water hammer phenomenon. A new modeling for quantitative explanation of the phenomena is also presented

  9. Proceedings: Condenser technology conference

    International Nuclear Information System (INIS)

    Tsou, J.L.; Mussalli, Y.G.

    1991-08-01

    Seam surface condenser and associated systems performance strongly affects availability and heat rate in nuclear and fossil power plants. Thirty-six papers presented at a 1990 conference discuss research results, industry experience, and case histories of condenser problems and solutions. This report contains papers on life extension, performance improvement, corrosion and failure analysis, fouling prevention, and recommendation for future R ampersand D. The information represents recent work on condenser problems and solutions to improve the procurement, operation, and maintenance functions of power plant personnel. Several key points follow: A nuclear and a fossil power plant report show that replacing titanium tube bundles improves condenser availability and performance. One paper reports 10 years of experience with enhanced heat transfer tubes in utility condensers. The newly developed enhanced condenser tubes could further improve condensing heat transfer. A new resistance summation method improves the accuracy of condenser performance prediction, especially for stainless steel and titanium tubed condensers. Several papers describe improved condenser fouling monitoring techniques, including a review of zebra mussel issues

  10. An experimental study of high pressure steam condensation in a vertical tube of passive secondary condensation system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Jae; No, Hee Cheon [KAIST, Taejon (Korea, Republic of)

    1998-07-01

    To investigate the physical parameters of PSCS (Passive Secondary Condensation System) which is a passive residual heat removal system of CP-1300, the high pressure condensation experiments are performed in a small scale experimental facility. The experimental parameters are the local heat flux and the transfer coefficient and the pressure drop in a condensation heat trasnfer. The film condensation heat transfer coefficients in a vertical tube are calculated from the measured wall temperature difference and compared with the analytical models. A new analytical condensation model is developed based on the annular film flow model. The present model gives marginally better results than those from the Shah model in comparison with the experimental data in the database. Also, experimental data are compared with the results of the RELAP5/MOD3.2 thermal hydraulic code. The RELAP5/MOD3.2 underpredicts the condensation heat transfer coefficients of the present experiment by 50 %.

  11. Bone scans in nasopharyngeal carcinoma: local experience

    International Nuclear Information System (INIS)

    Tiong, S.

    2004-01-01

    Introduction: Nasopharyngeal carcinoma (NPC) tops the list of malignancy in Malaysia and ranks first in male malignancy in the state of Sarawak. The majority of the NPC patients presented in the advanced stages and often with distal metastasis usually to the bones. In our local hospital is the new practice of bone scan using Tc99 started last year. Over a period of 9 months from July 2003 to March 2004, 41 NPC patients had the bone scans and our experience in these are reviewed and presented. Method: The NPC patients are selected consecutively including both new and treated patients. The scanner used is Siemen E.cam plus and Technecium (Tc99) the radio-active isotope used. The scan images are read and reported by qualified and trained Radiologists. The bone scans are requested from the ENT Specialist of the ENT department of the Hospital. The bone scan reports are checked by the ENT Specialists and the decisions made as to clinical correlation and further definitive imaging studies. Results: 41 NPC patients were included in the studies, 29 newly diagnosed and bone-canned before treatment started and 12 treated of which 3 being diagnosed having recurrent NPC. Of the 29 newly diagnosed patients, one was found true positive bone scan having increased radio-tracer uptake and confirmed Xray imagings. 3 of the treated patients had true positive bone scan with increased radio-tracer uptake and confirmed Xray imagings. Hence a total of 4 out of the 41 patients (9.8%) had bone metastasis on positive bone scans. Of the 29 newly diagnosed patients, 14 were found false positive bone scan having increased radio-tracer uptake but no confirmed X ray imagings. 4 of the treated patients had false positive bone scan with increased radio-tracer uptake but no confirmed X ray imagings. Hence a total of 18 out of the 41 patients (44%) had no bone metastasis on positive bone scans. There were 6 patients with symptoms referable to the bones' distal to the head and 2 had true positive bone

  12. Local agenda 21. The French experience

    International Nuclear Information System (INIS)

    2002-01-01

    In keeping with the Rio Declaration on Environment and Development, and with the ''Agenda 21'' Action program for the 21 Century, the French Minister of the Environment, in January 1993, and again on 11 May 1994, set up new mechanisms, entitled ''Urban Ecology Charters'' or ''Environmental Charters'', also described as ''Partnership Programmes for Sustainable Development''. Their purpose is to implement a new economic approach which, in the Rio spirit, encourages a sustainable form of development, characterized by the integration of environmental costs. Since 1999, a broad new legal text, the ''Act on Spatial Planning and Sustainable Development Policy'' encourages urban and rural local government to define and run development projects that refer to Chapter 28 of the Action 21 program of Rio. The development of Agenda 21 is now supported by contracts between the State and local authorities of various character, such as the large ''Regions'' (of which there are only 21 in France), local institutions responsible for managing urban agglomerations, smaller ad-hoc rural areas called ''Pays'', and some of the regional natural parks or reserves. Such development projects are required broadly to call upon the participation of, and partnership with concerned private and public stakeholders. They must support modes of production and consumption that are thrifty in resources (energy, water, soil, air, biodiversity), and also socially responsible towards populations of other countries and future generations. (author)

  13. Experience with the use of SF6 to locate condenser leakage in power plants

    International Nuclear Information System (INIS)

    Tondi, D.M.

    1988-01-01

    Condenser tube water inleakage is a prime source of contamination in power plant steam systems. Conventional techniques of leaking-tube detection require periods of reduced power operation. A new method, using sulfur hexafluoride as a tracer gas, can detect leaking tubes while the plant is operating. Sulfur hexafluoride is a gas that when entrained in the cooling water will follow the water through the leak, be volatilized by the vacuum and heat in the condenser, and be detected in the off-gas. The technique will provide positive identification of a leaking waterbox. Sulfur hexafluoride is innocuous, insoluble, thermally stable, and non-toxic. Its most important characteristic in this application is that it can be detected in very low concentration. This high sensitivity enables waterbox testing to be performed while the unit is on line and at full power. The technique has been used at more than 30 fossil and nuclear stations. Tests show that leaking waterboxes can be isolated, and that leaks of less than one gallon per day are readily detectable. There are several cost benefits associated with this technology. One which can be quantified is the cost for replacement power. The process of reducing power in order to silate a leaking waterbox can cost in excess of 30,000 dollars for even a small unit. In addition to direct cost savings, water chemistry can be improved since sensitivity to leakage is generally greater than station chemistry capabilities. Test results from service work at a range of typical plants will be discussed including: estimations of detected leak rates, injection points and rates, and approximately cost savings

  14. Edge localized modes control: experiment and theory

    International Nuclear Information System (INIS)

    Becoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P.; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Counsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Kamiya, K.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Loennroth, J.; Shimada, M.; Polevoi, A.; Federici, G.

    2005-01-01

    The paper reviews recent theoretical and experimental results focussing on the identification of the key factors controlling ELM energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. Present experiment and theory pointed out the benefit of the high plasma shaping, high q 95 and high pedestal density in reducing the ELM affected area and conductive energy losses in Type I ELMs. Small benign ELMs regimes in present machines (EDA, HRS, Type II, Grassy, QH, Type III in impurity seeded discharges at high δ ) and their relevance for ITER are reviewed. Recent studies of active control of ELMs using stochastic boundaries, small pellets and edge current generation are presented

  15. Chest trauma in children: A local experience

    International Nuclear Information System (INIS)

    Al-Saigh, A.; Fazili, Fiaz M.; Allam, Abdulla R.

    1999-01-01

    Chest trauma in childhood is relatively uncommon in clinical practice andhas been the subject of few reports in literature. This study was undertakento examine our experience in dealing with chest trauma in children. This wasa retrospective study of 74 children who sustained chest trauma and werereferred to King Fahd Hospital in Medina over a two-year period. The age,cause of injury, severity of injury, associated extrathoracic injuries,treatment and outcome were analyzed. The median age of patients was nineyears. Fifty-nine of them (80%) sustained blunt trauma in 62% of thechildren, gun shot wounds were seen in five and stab wounds in 10 children.Head injury was the most common injury associated with thoracic trauma andwas seen in 14 patients (19%) and associated intra-abdominal injuries wereseen in nine patients. Chest x-ray of the blunt trauma patients revealedfractured ribs in 24 children, pneumothorax in six, hemothorax in four,hemoneumothorax in three, and pulmonary contusions in 22 patients. Fifty onepercent of children were managed conservatively, 37% required tubethoracostomy, 8% were mechanically ventilated and 4% underwent thoractomy.The prevalence of chest trauma in children due to road traffic accidents ishigh in Saudi Arabia. Head injury is thought to be the most common associatedextrathoracic injuries, however, most of these patients can be managedconservatively. (author)

  16. The use of contained nuclear explosions to create underground reservoirs, and experience of operating these for gas condensate storage

    International Nuclear Information System (INIS)

    Kedrovskij, O.L.; Myasnikov, K.V.; Leonov, E.A.; Romadin, N.M.; Dorodnov, V.F.; Nikiforov, G.A.

    1975-01-01

    Investigations on the creation of underground reservoirs by means of nuclear explosions have been going on in the Soviet Union for many years. In this paper the authors consider three main kinds of sites or formations that can be used for constructing reservoirs by this method, namely, low-permeable rocks, worked-out mines and rock salt formations. Formulae are given for predicting the mechanical effect of an explosion in rocks, taking their strength characteristics into account. Engineering procedures are described for sealing and restoring the emplacement holes, so that they can be used for operating the underground reservoir. Experience with the contruction and operation of a 50 000 m 3 gas-condensate reservoir in a rock salt formation is described. In the appendix to the paper a method is presented for calculating the stability of spherical cavities created by nuclear explosions in rock salt, allowing for the development of elasto-plastic deformations and creep

  17. Few-Group Transport Analysis of the Core-Reflector Problem in Fast Reactor Cores via Equivalent Group Condensation and Local/Global Iteration

    International Nuclear Information System (INIS)

    Won, Jong Hyuck; Cho, Nam Zin

    2011-01-01

    In deterministic neutron transport methods, a process called fine-group to few-group condensation is used to reduce the computational burden. However, recent results on the core-reflector problem in fast reactor cores show that use of a small number of energy groups has limitation to describe neutron flux around core reflector interface. Therefore, researches are still ongoing to overcome this limitation. Recently, the authors proposed I) direct application of equivalently condensed angle-dependent total cross section to discrete ordinates method to overcome the limitation of conventional multi-group approximations, and II) local/global iteration framework in which fine-group discrete ordinates calculation is used in local problems while few-group transport calculation is used in the global problem iteratively. In this paper, an analysis of the core-reflector problem is performed in few-group structure using equivalent angle-dependent total cross section with local/global iteration. Numerical results are obtained under S 12 discrete ordinates-like transport method with scattering cross section up to P1 Legendre expansion

  18. Water Condensation

    DEFF Research Database (Denmark)

    Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund

    2014-01-01

    The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

  19. Controlling molecular condensation/diffusion of copper phthalocyanine by local electric field induced with scanning tunneling microscope tip

    Science.gov (United States)

    Nagaoka, Katsumi; Yaginuma, Shin; Nakayama, Tomonobu

    2018-02-01

    We have discovered the condensation/diffusion phenomena of copper phthalocyanine (CuPc) molecules controlled with a pulsed electric field induced by the scanning tunneling microscope tip. This behavior is not explained by the conventional induced dipole model. In order to understand the mechanism, we have measured the electronic structure of the molecule by tunneling spectroscopy and also performed theoretical calculations on molecular orbitals. These data clearly indicate that the molecule is positively charged owing to charge transfer to the substrate, and that hydrogen bonding exists between CuPc molecules, which makes the molecular island stable.

  20. Experience in oil field processing of gas and condensate at the Shatlyk deposits

    Energy Technology Data Exchange (ETDEWEB)

    Dalmatov, V.V.; Chernikov, Ye.I.; Govorun, V.P.; Turevskiy, Ye.N.

    1983-01-01

    The operation of installations for preparing gas are analyzed, along with the operation of individual technological devices at the Shatlyk deposit, the basic things which hinder the support of the designed low temperature conditions are shown and recommendations for standardizing the operation of the technological installations are given. Experience in the operation of the gas preparation installations at the Shatlyk deposit is recommended for use in deposits being introduced into development.

  1. Dropwise condensation on inclined textured surfaces

    CERN Document Server

    Khandekar, Sameer

    2014-01-01

    Dropwise Condensation on Textured Surfaces presents a holistic framework for understanding dropwise condensation through mathematical modeling and meaningful experiments. The book presents a review of the subject required to build up models as well as to design experiments. Emphasis is placed on the effect of physical and chemical texturing and their effect on the bulk transport phenomena. Application of the model to metal vapor condensation is of special interest. The unique behavior of liquid metals, with their low Prandtl number and high surface tension, is also discussed. The model predicts instantaneous drop size distribution for a given level of substrate subcooling and derives local as well as spatio-temporally averaged heat transfer rates and wall shear stress.

  2. Percutaneous vertebroplasty under local anaesthesia: feasibility regarding patients' experience

    International Nuclear Information System (INIS)

    Bonnard, Eric; Foti, Pauline; Amoretti, Nicolas; Kastler, Adrian

    2017-01-01

    Evaluate patients' intraoperative experience of percutaneous vertebroplasty (PV) performed without general anaesthesia in order to assess the feasibility of local anaesthesia and simple analgesic medication as pain control protocol. Ninety-five patients who underwent single-site PV were consecutively included in the study between 2011 and 2013. Each procedure was achieved under local anaesthesia and perfusion of paracetamol, tramadol and dolasetron, with combined CT and fluoroscopy guidance. Numeric pain scale (NPS) was collected before, during and after intervention. After intervention, patients were asked to evaluate their experience as ''very bad'', ''bad'', ''fair'', ''good'' or ''very good'', independently of the pain. Indications for vertebroplasty were osteopenic fractures (78 %), aggressive angiomas (13 %) and somatic tumours (9 %). In 76 % of cases, patients' experience was described as ''very good'' (44 %) or ''good'' (32 %), whereas 19 % described it as ''fair'' and 5 % as ''very bad''. Mean operative NPS was 5.5. After intervention, NPS was significantly lower with a decrease of 4.5 points. No differences were found according to the localization, type of lesion, age or sex either in terms of experience or NPS. Percutaneous vertebroplasty is feasible under local anaesthesia alone, with a very good or good experience in 76 % of the patients. (orig.)

  3. Steam condenser

    International Nuclear Information System (INIS)

    Masuda, Fujio

    1980-01-01

    Purpose: To enable safe steam condensation by providing steam condensation blades at the end of a pipe. Constitution: When high temperature high pressure steam flows into a vent pipe having an opening under water in a pool or an exhaust pipe or the like for a main steam eacape safety valve, non-condensable gas filled beforehand in the steam exhaust pipe is compressed, and discharged into the water in the pool. The non-condensable gas thus discharged from the steam exhaust pipe is introduced into the interior of the hollow steam condensing blades, is then suitably expanded, and thereafter exhausted from a number of exhaust holes into the water in the pool. In this manner, the non-condensable gas thus discharged is not directly introduced into the water in the pool, but is suitable expanded in the space of the steam condensing blades to suppress extreme over-compression and over-expansion of the gas so as to prevent unstable pressure vibration. (Yoshihara, H.)

  4. Effects of local mass anomalies in Eoetvoes-like experiments

    International Nuclear Information System (INIS)

    Talmadge, C.; Aronson, S.H.; Fischbach, E.

    1986-01-01

    We consider in detail the effects of local mass anomalies in Eoetvoes-like experiments. It is shown that in the presence of an intermediate-range non-gravitational force, the dominant contributions to both the sign and magnitude of the Eoetvoes anomaly may come from nearby masses and not from the earth as a whole. This observation has important implications in the design and interpretation of future experiments, and in the formulation of unified theories incorporating new intermediate-range forces

  5. Nobel Lecture: Bose-Einstein condensation in a dilute gas, the first 70 years and some recent experiments

    International Nuclear Information System (INIS)

    Cornell, E.A.; Wieman, C.E.

    2002-01-01

    Bose-Einstein condensation, or BEC, has a long and rich history dating from the early 1920s. In this article we will trace briefly over this history and some of the developments in physics that made possible our successful pursuit of BEC in a gas. We will then discuss what was involved in this quest. In this discussion we will go beyond the usual technical description to try and address certain questions that we now hear frequently, but are not covered in our past research papers. These are questions along the lines of: How did you get the idea and decide to pursue it? Did you know it was going to work? How long did it take you and why? We will review some our favorites from among the experiments we have carried out with BEC. There will then be a brief encore on why we are optimistic that BEC can be created with nearly any species of magnetically trappable atom. Throughout this article we will try to explain what makes BEC in a dilute gas so interesting, unique, and experimentally challenging

  6. Modeling of local steam condensation on walls in presence of non-condensable gases. Application to a loca calculation in reactor containment using the multidimensional geyser/tonus code

    Energy Technology Data Exchange (ETDEWEB)

    Benet, L.V.; Caroli, C.; Cornet, P. [Commissariat a l`Energie Atomique, Gif sur Yvette (France)] [and others

    1995-09-01

    This paper reports part of a study of possible severe pressurized water reactor (PWR) accidents. The need for containment modeling, and in particular for a hydrogen risk study, was reinforced in France after 1990, with the requirement that severe accidents must be taken into account in the design of future plants. This new need of assessing the transient local hydrogen concentration led to the development, in the Mechanical Engineering and Technology Department of the French Atomic Energy Commission (CEA/DMT), of the multidimensional code GEYSER/TONUS for containment analysis. A detailed example of the use of this code is presented. The mixture consisted of noncondensable gases (air or air plus hydrogen) and water vapor and liquid water. This is described by a compressible homogeneous two-phase flow model and wall condensation is based on the Chilton-Colburn formula and the analogy between heat and mass transfer. Results are given for a transient two-dimensional axially-symmetric computation for the first hour of a simplified accident sequence. In this there was an initial injection of a large amount of water vapor followed by a smaller amount and by hydrogen injection.

  7. Condensed landscape experience

    DEFF Research Database (Denmark)

    Earon, Ofri

    2011-01-01

    demands, quality of space, mixture of functions, urban complexity, public life and cultural heritage. In order to launch such an approach, an understanding of the spatial, social and environmental significance of a radical re-thinking of relationships between architecture and landscape is necessary...... is becoming a standard in contemporary architecture. Merging architecture and landscape has turned into a principle for an ecological / sustainable architecture. Yet, my aspiration is to achieve a wider interaction involving an application of a wider range of perspectives, such as: urban identity, social......‘Re-thinking interaction between landscape and urban buildings’ participates in an interdisciplinary discourse about the theoretical and practical advantages of openly juxtaposing landscape and architecture without having one more advanced in importance. Recently, the greenification of buildings...

  8. Condensed landscape experience

    DEFF Research Database (Denmark)

    Earon, Ofri

    2011-01-01

    ‘Re-thinking interaction between landscape and urban buildings’ participates in an interdisciplinary discourse about the theoretical and practical advantages of openly juxtaposing landscape and architecture without having one more advanced in importance. Recently, the greenification of buildings...... demands, quality of space, mixture of functions, urban complexity, public life and cultural heritage. In order to launch such an approach, an understanding of the spatial, social and environmental significance of a radical re-thinking of relationships between architecture and landscape is necessary...

  9. Localization and loss of coherence in molecular double slit experiments

    Energy Technology Data Exchange (ETDEWEB)

    Langer, Burkhard [Institut fuer Chemie und Biochemie - Physikalische und Theoretische Chemie, Freie Universitaet Berlin, Takustr. 3, D-14195 Berlin (Germany); Becker, Uwe, E-mail: langer@gpta.d, E-mail: becker_u@fhi-berlin.mpg.d [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany)

    2009-11-01

    In their famous paper Einstein, Podolsky and Rosen questioned 1935 the completeness of quantum mechanics concerning a local realistic description of our reality. They argued on the basis of superpositions of position and momentum states against the inherent non-locality and loss of information on prior conditions by quantum mechanics. This pioneering proposal was, however, too vague to be implemented in any experimental proof. Consequently, angular momentum related variables such as the polarization of light became the working horse of all experiments proving the EPR predictions. However, the spin and its related polarization properties are abstract quantities compared to position and momentum. Here we present the first evidence that non-locality and loss of prior quantum state information occurs also for position in ordinary space. This shows that the tunnelling effect and entanglement are inherently correlated.

  10. Localization and loss of coherence in molecular double slit experiments

    International Nuclear Information System (INIS)

    Langer, Burkhard; Becker, Uwe

    2009-01-01

    In their famous paper Einstein, Podolsky and Rosen questioned 1935 the completeness of quantum mechanics concerning a local realistic description of our reality. They argued on the basis of superpositions of position and momentum states against the inherent non-locality and loss of information on prior conditions by quantum mechanics. This pioneering proposal was, however, too vague to be implemented in any experimental proof. Consequently, angular momentum related variables such as the polarization of light became the working horse of all experiments proving the EPR predictions. However, the spin and its related polarization properties are abstract quantities compared to position and momentum. Here we present the first evidence that non-locality and loss of prior quantum state information occurs also for position in ordinary space. This shows that the tunnelling effect and entanglement are inherently correlated.

  11. Localization and loss of coherence in molecular double slit experiments

    Science.gov (United States)

    Langer, Burkhard; Becker, Uwe

    2009-11-01

    In their famous paper Einstein, Podolsky and Rosen questioned 1935 the completeness of quantum mechanics concerning a local realistic description of our reality. They argued on the basis of superpositions of position and momentum states against the inherent non-locality and loss of information on prior conditions by quantum mechanics. This pioneering proposal was, however, too vague to be implemented in any experimental proof. Consequently, angular momentum related variables such as the polarization of light became the working horse of all experiments proving the EPR predictions. However, the spin and its related polarization properties are abstract quantities compared to position and momentum. Here we present the first evidence that non-locality and loss of prior quantum state information occurs also for position in ordinary space. This shows that the tunnelling effect and entanglement are inherently correlated

  12. SHERLOCK: Simple Human Experiments Regarding Locally Observed Collective Knowledge

    Science.gov (United States)

    2015-12-01

    Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to... aware approach in coalition decision making at or near the network edge. The studies, named SHERLOCK (for Simple Human Experiments Regarding Locally...character’s location, shirt colour , preferred fruit, and hobby — are discoverable by visiting a set of locations around a university building. In

  13. A CFD study of wave influence on film steam condensation in the presence of non-condensable gas

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianmao, E-mail: xm-wang11@mails.tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Chang, Huajian, E-mail: changhj@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Corradini, Michael, E-mail: corradini@engr.wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

    2016-08-15

    Highlights: • A condensation model is incorporated in the ANSYS FLUENT. • Different turbulence models are evaluated for flows over wavy surfaces. • Wavy surfaces with and without moving velocities are used to model the wave. • Various wavy surfaces with different wave heights and wavelengths are selected. • Wave influence on film steam condensation is investigated. - Abstract: Steam condensation plays an important role in removing heat from the containment of a nuclear plant during postulated accidents. However, due to the presence of non-condensable gases such as air and hydrogen in the containment, the condensation rate can decrease dramatically. Under certain conditions, the condensate film on the cold containment walls can affect the overall heat transfer rate. The wavy interface of the condensate film is a factor and is usually believed to enhance the condensation rate, since the waves can both increase the interfacial area and disturb the non-condensable gas boundary layer. However, it is not clear how to properly account for this factor and what is its quantitative influence in experiments. In this work, a CFD approach is applied to study the wave effects on film condensation in the presence of non-condensable gas. Wavy surfaces with and without moving velocities are used to replace the wavy interface of the falling film. A condensation model is incorporated in the ANSYS FLUENT simulation and a realizable k–ε turbulence model is applied. Various wavy surfaces with different wave heights and wavelengths are selected to conduct numerical experiments with a wide range of gas velocities. The results show that the wave structure can enhance condensation rate up to ten percent mainly due to the alteration of local flow structures in the gas phase. The increments of the condensation rate due to the wavy interface can vary with different gas velocities. The investigation shows that a multiplication factor accounts for the wave effects on film

  14. UPTF-TRAM experiments for SBLOCA: Evaluation of condensation processes in TRAM tests A6 and A7

    Energy Technology Data Exchange (ETDEWEB)

    Sonneburg, H.G.; Tuunanen, J.; Palazov, V.V. [Gesellschaft fuer Anlagen-und Reaktorsicherheit (GRS), Muenchen (Germany)

    1995-09-01

    The investigation of thermal-hydraulic phenomena related to reactor transients with accident management measures is the goal of the TRansient and accident Management (TRAM) experimental programme being carried out at the Upper Plenum Test Facility (UPTF) at Mannheim (Germany). These experimental investigations and test analyses are funded by the German Federal Minister for Research and Technology (BMFT). The UPTF simulates these phenomena in a 1:1 such relative to the dimension of a PWR. Condensation of steam during Emergency Core Cooling (ECC) water injection from accumulators into the primary system is one of the phenomena studied within the accumulators into the primary system is one of the phenomena studied within the TRAM programme. This phenomenon partly controls the efficiency of accumulator injection if the high pressure safety systems fail. Beside this, the condensation within the nitrogen inside the accumulator for a certain period controls the pressure development inside the accumulator. Thus, both condensation phenomena determine the ECC flow rate delivered to the primary system. Concerning the condensation inside the primary system, this is also of safety relevance in the case of Pressurized Thermal Shock (PTS) during cold leg injection.

  15. Local beam position feedback experiments on the ESRF storage ring

    International Nuclear Information System (INIS)

    Chung, Y.; Kahana, E.; Kirchman, J.

    1995-01-01

    This paper describes the results of local beam position feedback experiments conducted on the ESRF storage ring using digital signal processing (DSP) under the trilateral agreement of collaboration among ESRF, APS, and SPring-8. Two rf beam position monitors (BPMS) in the, upstream and downstream of the insertion device (ID) and two x-ray BPMs in the sixth cell were used to monitor the electron beam and the x-ray beam emitted from the ID, respectively. The local bump coefficients were obtained using the technique of singular value decomposition (SVD) on the global response matrix for the bump magnets and all the available BPMs outside the local bump. The local response matrix was then obtained between the two three-magnet bumps and the position monitors. The data sampling frequency was 4 kHz and a proportional, integral, and derivative (PID) controller was used. The result indicates the closed-loop feedback bandwidth close to 100 Hz and clear attenuation (∼ -40 dB) of the 7-Hz beam motion due to girder vibration resonance. Comparison of the results using the rf BPMs and x-ray BPMs will be also discussed

  16. Optimal design of condenser weight

    International Nuclear Information System (INIS)

    Zheng Jing; Yan Changqi; Wang Jianjun

    2011-01-01

    The condenser is an important component in nuclear power plants, which dimension and weight will effect the economical performance and the arrangement of the nuclear power plants. In this paper, the calculation model is established according to the design experience. The corresponding codes are also developed, and the sensitivity of design parameters which influence the condenser weight is analyzed. The present design optimization of the condenser, taking the weight minimization as the objective, is carried out with the self-developed complex-genetic algorithm. The results show that the reference condenser design is far from the best scheme, and also verify the feasibility of the complex-genetic algorithm. (authors)

  17. Learning from games: Stakeholders’ experiences involved in local health policy

    DEFF Research Database (Denmark)

    Spitters, Hilde; van de Goor, Ien; Juel Lau, Cathrine

    2018-01-01

    Since public health problems are complex and the related policies need to address a wide range of sectors, cross-sectoral collaboration is beneficial. One intervention focusing on stimulating collaboration is a ‘policy game’. The focus on specific problems facilitates relationships between...... the stakeholders and stimulates cross-sectoral policymaking. The present study explores stakeholders’ learning experiences with respect to the collaboration process in public health policymaking. This was achieved via their game participation, carried out in real-life stakeholder networks in the Netherlands...... the collaboration processes in local policymaking. Specific learning experiences were related to: (i) the stakeholder network, (ii) interaction and (iii) relationships. The game also increased participant’s understanding of group dynamics and need for a coordinator in policymaking. This exploratory study shows...

  18. Improvements to TRAC models of condensing stratified flow. Pt. 1

    International Nuclear Information System (INIS)

    Zhang, Q.; Leslie, D.C.

    1991-12-01

    Direct contact condensation in stratified flow is an important phenomenon in LOCA analyses. In this report, the TRAC interfacial heat transfer model for stratified condensing flow has been assessed against the Bankoff experiments. A rectangular channel option has been added to the code to represent the experimental geometry. In almost all cases the TRAC heat transfer coefficient (HTC) over-predicts the condensation rates and in some cases it is so high that the predicted steam is sucked in from the normal outlet in order to conserve mass. Based on their cocurrent and countercurrent condensing flow experiments, Bankoff and his students (Lim 1981, Kim 1985) developed HTC models from the two cases. The replacement of the TRAC HTC with either of Bankoff's models greatly improves the predictions of condensation rates in the experiment with cocurrent condensing flow. However, the Bankoff HTC for countercurrent flow is preferable because it is based only on the local quantities rather than on the quantities averaged from the inlet. (author)

  19. Polariton condensates

    International Nuclear Information System (INIS)

    Snoke, David; Littlewood, Peter

    2010-01-01

    Most students of physics know about the special properties of Bose-Einstein condensates (BECs) as demonstrated in the two best-known examples: superfluid helium-4, first reported in 1938, and condensates of trapped atomic gases, first observed in 1995. (See the article by Wolfgang Ketterle in PHYSICS TODAY, December 1999, page 30.) Many also know that superfluid 3 He and superconducting metals contain BECs of fermion pairs. An underlying principle of all those condensed-matter systems, known as quantum fluids, is that an even number of fermions with half-integer spin can be combined to make a composite boson with integer spin. Such composite bosons, like all bosons, have the property that below some critical temperature--roughly the temperature at which the thermal de Broglie wavelength becomes comparable to the distance between the bosons--the total free energy is minimized by having a macroscopic number of bosons enter a single quantum state and form a macroscopic, coherent matter wave. Remarkably, the effect of interparticle repulsion is to lead to quantum mechanical exchange interactions that make that state robust, since the exchange interactions add coherently.

  20. Modeling bubble condenser containment with computer code COCOSYS: post-test calculations of the main steam line break experiment at ELECTROGORSK BC V-213 test facility

    International Nuclear Information System (INIS)

    Lola, I.; Gromov, G.; Gumenyuk, D.; Pustovit, V.; Sholomitsky, S.; Wolff, H.; Arndt, S.; Blinkov, V.; Osokin, G.; Melikhov, O.; Melikhov, V.; Sokoline, A.

    2005-01-01

    Containment of the WWER-440 Model 213 nuclear power plant features a Bubble Condenser, a complex passive pressure suppression system, intended to limit pressure rise in the containment during accidents. Due to lack of experimental evidence of its successful operation in the original design documentation, the performance of this system under accidents with ruptures of large high-energy pipes of the primary and secondary sides remains a known safety concern for this containment type. Therefore, a number of research and analytical studies have been conducted by the countries operating WWER-440 reactors and their Western partners in the recent years to verify Bubble Condenser operation under accident conditions. Comprehensive experimental research studies at the Electrogorsk BC V-213 test facility, commissioned in 1999 in Electrogorsk Research and Engineering Centre (EREC), constitute essential part of these efforts. Nowadays this is the only operating large-scale facility enabling integral tests on investigation of the Bubble Condenser performance. Several large international research projects, conducted at this facility in 1999-2003, have covered a spectrum of pipe break accidents. These experiments have substantially improved understanding of the overall system performance and thermal hydraulic phenomena in the Bubble Condenser Containment, and provided valuable information for validating containment codes against experimental results. One of the recent experiments, denoted as SLB-G02, has simulated steam line break. The results of this experiment are of especial value for the engineers working in the area of computer code application for WWER-440 containment analyses, giving an opportunity to verify validity of the code predictions and identify possibilities for model improvement. This paper describes the results of the post-test calculations of the SLB-G02 experiment, conducted as a joint effort of GRS, Germany and Ukrainian technical support organizations for

  1. Design and performance of a mechanically pumped two-phase loop to support the evaporation-condensation experiments on the TZ1

    Directory of Open Access Journals (Sweden)

    Z.R. Wang

    2017-09-01

    Full Text Available The mechanically pumped two-phase loop (MPTL has the advantages of long distance heat transport, high heat density and good temperature control. On TZ1, the MPTL technology is adopted to support a series experiments of evaporation and condensation. The main objective is to provide accurate (±0.5 ℃ temperature control from −5 ℃ to 40 ℃ and remove 80 W heat from the experimental setup. In this paper, the requirements, system design, hardware and performance of the MPTL are introduced.

  2. Bench scale experiments for the remediation of Hanford Waste Treatment Plant low activity waste melter off-gas condensate

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M.L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Poirier, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-08-11

    The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter, so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.

  3. Preliminary experiments on surface flow visualization in the cryogenic wind tunnel by use of condensing or freezing gases

    Science.gov (United States)

    Goodyer, M. J.

    1988-01-01

    Cryogenic wind tunnel users must have available surface flow visualization techniques to satisfy a variety of needs. While the ideal from an aerodynamic stand would be non-intrusive, until an economical technique is developed there will be occasions when the user will be prepared to resort to an intrusive method. One such method is proposed, followed by preliminary evaluation experiments carried out in environments representative of the cryogenic nitrogen tunnel. The technique uses substances which are gases at normal temperature and pressure but liquid or solid at cryogenic temperatures. These are deposited on the model in localized regions, the patterns of the deposits and their subsequent melting or evaporation revealing details of the surface flow. The gases were chosen because of the likelihood that they will not permanently contaminate the model or tunnel. Twenty-four gases were identified as possibly suitable and four of these were tested from which it was concluded that surface flow direction can be shown by the method. Other flow details might also be detectable. The cryogenic wind tunnel used was insulated on the outside and did not show signs of contamination.

  4. Ghost condensate and generalized second law

    International Nuclear Information System (INIS)

    Mukohyama, Shinji

    2009-01-01

    Dubovsky and Sibiryakov recently proposed a scenario in which particles of different species propagate with different speeds due to their direct couplings to ghost condensate. It was argued that this extended version of ghost condensate allows a gedanken experiment leading to violation of the generalized second law. However, in the original ghost condensate scenario, difference in propagation speeds is suppressed by M 2 /M Pl 2 , where M is the order parameter of spontaneous Lorentz breaking and M Pl is the Planck scale. In this case the energy transfer necessary for the gedanken experiment is so slow that the timescale of decrease of entropy, if any, is always longer than the Jeans timescale of ghost condensate. Hence the generalized second law is not violated by the gedanken experiment in the original ghost condensate scenario. This conclusion trivially extends to gauged ghost condensation by taking into account accretion of gauged ghost condensate into a black hole.

  5. Hydrogen behavior in ice condenser containments

    Energy Technology Data Exchange (ETDEWEB)

    Lundstroem, P.; Hongisto, O. [Power Plant Lab., Helsinki (Finland); Theofanous, T.G. [Univ. of California, Santa Barbara, CA (United States)] [and others

    1995-09-01

    A new hydrogen management strategy is being developed for the Loviisa ice condenser containment. The strategy relies on containment-wide natural circulations that develop, once the ice condenser doors are forced open, to effectively produce a well-mixed behavior, and a correspondingly slow rise in hydrogen concentration. Levels can then be kept low by a distributed catalytic recombiner system, and (perhaps) an igniter system as a backup, while the associated energy releases can be effectively dissipated in the ice bed. Verification and fine-tuning of the approach is carried out experimentally in the VICTORIA facility and by associated scaling/modelling studies. VICTORIA represents an 1/15th scale model of the Loviisa containment, hydrogen is simulated by helium, and local concentration measurements are obtained by a newly developed instrument specifically for this purpose, called SPARTA. This paper is focused on experimental results from several key experiments that provide a first delineation of key behaviors.

  6. Bose-Einstein condensation in microgravity.

    Science.gov (United States)

    van Zoest, T; Gaaloul, N; Singh, Y; Ahlers, H; Herr, W; Seidel, S T; Ertmer, W; Rasel, E; Eckart, M; Kajari, E; Arnold, S; Nandi, G; Schleich, W P; Walser, R; Vogel, A; Sengstock, K; Bongs, K; Lewoczko-Adamczyk, W; Schiemangk, M; Schuldt, T; Peters, A; Könemann, T; Müntinga, H; Lämmerzahl, C; Dittus, H; Steinmetz, T; Hänsch, T W; Reichel, J

    2010-06-18

    Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.

  7. Condensed elementary particle matter

    International Nuclear Information System (INIS)

    Kajantie, K.

    1996-01-01

    Quark matter is a special case of condensed elementary particle matter, matter governed by the laws of particle physics. The talk discusses how far one can get in the study of particle matter by reducing the problem to computations based on the action. As an example the computation of the phase diagram of electroweak matter is presented. It is quite possible that ultimately an antireductionist attitude will prevail: experiments will reveal unpredicted phenomena not obviously reducible to the study of the action. (orig.)

  8. Aerosol-Cloud Interactions During Puijo Cloud Experiments - The effects of weather and local sources

    Science.gov (United States)

    Komppula, Mika; Portin, Harri; Leskinen, Ari; Romakkaniemi, Sami; Brus, David; Neitola, Kimmo; Hyvärinen, Antti-Pekka; Kortelainen, Aki; Hao, Liqing; Miettinen, Pasi; Jaatinen, Antti; Ahmad, Irshad; Lihavainen, Heikki; Laaksonen, Ari; Lehtinen, Kari E. J.

    2013-04-01

    The Puijo measurement station has provided continuous data on aerosol-cloud interactions since 2006. The station is located on top of the Puijo observation tower (306 m a.s.l, 224 m above the surrounding lake level) in Kuopio, Finland. The top of the tower is covered by cloud about 15 % of the time, offering perfect conditions for studying aerosol-cloud interactions. With a twin-inlet setup (total and interstitial inlets) we are able to separate the activated particles from the interstitial (non-activated) particles. The continuous twin-inlet measurements include aerosol size distribution, scattering and absorption. In addition cloud droplet number and size distribution are measured continuously with weather parameters. During the campaigns the twin-inlet system was additionally equipped with aerosol mass spectrometer (AMS) and Single Particle Soot Photometer (SP-2). This way we were able to define the differences in chemical composition of the activated and non-activated particles. Potential cloud condensation nuclei (CCN) in different supersaturations were measured with two CCN counters (CCNC). The other CCNC was operated with a Differential Mobility Analyzer (DMA) to obtain size selected CCN spectra. Other additional measurements included Hygroscopic Tandem Differential Mobility Analyzer (HTDMA) for particle hygroscopicity. Additionally the valuable vertical wind profiles (updraft velocities) are available from Halo Doppler lidar during the 2011 campaign. Cloud properties (droplet number and effective radius) from MODIS instrument onboard Terra and Aqua satellites were retrieved and compared with the measured values. This work summarizes the two latest intensive campaigns, Puijo Cloud Experiments (PuCE) 2010 & 2011. We study especially the effect of the local sources on the cloud activation behaviour of the aerosol particles. The main local sources include a paper mill, a heating plant, traffic and residential areas. The sources can be categorized and identified

  9. [Local public health networks. Apropos of an experience].

    Science.gov (United States)

    Guix, Joan; Bocio, Ana; Ferràs, Joaquim; Margalef, Jordi; Osanz, Anna C; Serrano, Mónica; Sentenà, Anna

    2013-01-01

    Public health action on a territory is complex and requires the involvement of multiple actors, who do not always act coordinately. Networks of organizations structures including the whole of the local actors facilitate the generation of synergies and enable greater effectiveness and efficiency of the joint action from the different actors on a same landscape. We present 3 years experience of four Public Health Committees in a region of Catalonia (Spain), composed by the main actors in public health planning. Each of the committees is organized on a plenary and working groups on issues arising from the regional health diagnosis, and coincident with the Health Plan of the Region. Coordination in no case implies the loss or dilution of the firm of the actor generator of intervention initiative in public health, but their empowerment and collaboration by the other actors. In conclusion welcomes the creation of a culture of collaboration and synergies between the different organizations concerned. Lack of specificity is observed in establishing operational objectives, and the need for greater coordination and involvement of the components of the various working groups. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

  10. Treatment of localized prostate cancer with brachytherapy: six years experience

    International Nuclear Information System (INIS)

    Martinez, Pablo; Dourado, Leandro; Giudice, Carlos; Villamil, Wenceslao; Palacios, Victor; Sardi, Mabel; Damia, Oscar

    2006-01-01

    a biochemical relapse. One of them was submitted to a recovery radical prostatectomy and another one has a full androgenic block. The remaining five patients were not submitted to any further treatment to the date. No prostate RTU was required for any patient. Complications were disurya 27%, rectal disorder 27% and acute urine retention 5%. 58% of the patients did not manifest any complication. 98% of the patients claim to have an acceptable quality of life. Conclusion: According to our experience, we can assert that prostate brachytherapy is efficient for localized prostate cancer. The proper selection of patients allows the obtaining of good oncological results. Complications appeared in a low percentage and no case was serious. The quality of life of the patients after the implant is excellent. (author) [es

  11. Condensation of exciton polaritons

    International Nuclear Information System (INIS)

    Kasprzak, J.

    2006-10-01

    Because of their unique property of bringing pure quantum effects into the real world scale, phase transitions towards condensed phases - like Bose-Einstein condensation (BEC), superfluidity, and superconductivity - have always fascinated scientists. The BEC, appearing upon cooling a gas of bosons below a critical temperature, has been given a striking demonstration in dilute atomic gases of rubidium atoms at temperatures below 200 nK. By confining photons in a semiconductor micro-cavity, and strongly coupling them to electronic excitations, one may create polaritons. These bosonic quasi-particles are 10 9 times lighter than rubidium atoms, thus theoretically allowing a BEC at standard cryogenic temperatures. Here we detail a comprehensive set of experiments giving compelling evidence for a BEC of polaritons. Above a critical density, we observe massive occupation of the ground state, developing from a thermalized and saturated distribution of the polariton population at (16-20) K. We demonstrate as well the existence of a critical temperature for this transition. The spontaneous onset of a coherent state is manifested by the increase of temporal coherence, the build-up of long-range spatial coherence and the reduction of the thermal noise observed in second order coherence experiments. The marked linear polarization of the emission from the condensate is also measured. All of these findings indicate the spontaneous onset of a macroscopic quantum phase. (author)

  12. An analysis direct-contact condensation in horizontal cocurrent stratified flow of steam and cold water

    International Nuclear Information System (INIS)

    Lee, Suk Ho; Kim, Hho Jung

    1992-01-01

    The physical benchmark problem on the direct-contact condensation under the horizontal cocurrent stratified flow was analyzed using the RELAP5/MOD2 and /MOD3 one-dimensional model. Analysis was performed for the Northwestern experiments, which involved condensing steam/water flow in a rectangular channel. The study showed that the RELAP5 interfacial heat transfer model, under the horizontal stratified flow regime, predicted the condensation rate well though the interfacial heat transfer area was underpredicted. However, some discrepancies in water layer thickness and local heat transfer coefficient with experimental results were found especially when there is a wavy interface, and those were satisfied only within the range. (Author)

  13. Condensation model for the ESBWR passive condensers

    International Nuclear Information System (INIS)

    Revankar, S. T.; Zhou, W.; Wolf, B.; Oh, S.

    2012-01-01

    In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data from separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)

  14. Experience of Percutaneous Trigger Finger Release under Local ...

    African Journals Online (AJOL)

    New Delhi, India. ... This procedure is easy, quicker, less complications and economical with good results. ... Sahu and Gupta: Trigger finger release under local anesthesia .... the most cost-effective treatment is two trials of corticosteroid.

  15. Women care about local knowledge, experiences from ethnomycology

    Directory of Open Access Journals (Sweden)

    Garibay-Orijel Roberto

    2012-07-01

    Full Text Available Abstract Gender is one of the main variables that influence the distribution of local knowledge. We carried out a literature review concerning local mycological knowledge, paying special attention to data concerning women’s knowledge and comparative gender data. We found that unique features of local mycological knowledge allow people to successfully manage mushrooms. Women are involved in every stage of mushroom utilization from collection to processing and marketing. Local mycological knowledge includes the use mushrooms as food, medicine, and recreational objects as well as an aid to seasonal household economies. In many regions of the world, women are often the main mushroom collectors and possess a vast knowledge about mushroom taxonomy, biology, and ecology. Local experts play a vital role in the transmission of local mycological knowledge. Women participate in the diffusion of this knowledge as well as in its enrichment through innovation. Female mushroom collectors appreciate their mycological knowledge and pursue strategies and organization to reproduce it in their communities. Women mushroom gatherers are conscious of their knowledge, value its contribution in their subsistence systems, and proudly incorporate it in their cultural identity.

  16. Solving local problems through local involvement? Experiences from Danish Urban Regeneration

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole

    -down approaches or massive public subsidies, the public regeneration schemes from the last decade have increasingly emphasized the need for involving local actors in the urban regeneration e.g. through partnerships, network building, involvement and participation of local actors and institutions, and financially...... agenda, and what can be learned from the development so far. Although ‘local involvement’ is a commonly used term in various urban regeneration programs, it can have many different meanings and implications. Therefore, the paper will discuss local involvement in the urban regeneration based on four...

  17. Enhanced Condensation Heat Transfer

    Science.gov (United States)

    Rose, John Winston

    The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.

  18. Simulation of containment atmosphere stratification experiment using local instantaneous description

    International Nuclear Information System (INIS)

    Babic, M.; Kljenak, I.

    2004-01-01

    An experiment on mixing and stratification in the atmosphere of a nuclear power plant containment at accident conditions was simulated with the CFD code CFX4.4. The original experiment was performed in the TOSQAN experimental facility. Simulated nonhomogeneous temperature, species concentration and velocity fields are compared to experimental results. (author)

  19. Clinical experience with intraoperative radiotherapy for locally advanced colorectal cancer

    International Nuclear Information System (INIS)

    Shibamoto, Yuta; Takahashi, Masaharu; Abe, Mitsuyuki

    1988-01-01

    Intraoperative radiotherapy (IORT) was performed on 20 patients with colorectal cancer. IORT with a single dose of 20 to 40 Gy was delivered to the residual tumor, tumor bed, and/or lymphnode regions. Although most of the patients had advanced lesions, local control was achieved in 67 % of the patients when IORT was combined with tumor resection, and 4 patients survived more than 5 years. There were no serious complications, except for contracture or atrophy of the psoas muscle seen in 2 patients. IORT combined with external beam radiotherapy should be a useful adjuvant therapy to surgery for locally advanced colorectal cancer. (author)

  20. Condensation coefficient of water in a weak condensation state

    International Nuclear Information System (INIS)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-01-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  1. Condensation coefficient of water in a weak condensation state

    Science.gov (United States)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-07-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  2. Advances in modelling of condensation phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Zaltsgendler, E. [Ontario Hydro Nuclear, Toronto (Canada); Hanna, B. [Atomic Energy of Canada Limited, Pinawa, Manitoba (Canada)

    1997-07-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

  3. Advances in modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Liu, W.S.; Zaltsgendler, E.; Hanna, B.

    1997-01-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described

  4. Distributed and collaborative: Experiences of local leadership of a first-year experience program

    Directory of Open Access Journals (Sweden)

    Jo McKenzie

    2017-07-01

    Full Text Available Local level leadership of the first year experience (FYE is critical for engaging academic and professional staff in working collaboratively on a whole of institution focus on student transition and success. This paper describes ways in which local informal leadership is experienced at faculty level in an institutional FYE program, based on interviews with faculty coordinators and small grant recipients. Initial analysis using the distributed leadership tenets described by Jones, Hadgraft, Harvey, Lefoe, and Ryland (2014 revealed features that enabled success, such as collaborative communities, as well as faculty differences influenced by the strength of the external mandate for change in the FYE. More fine-grained analysis indicated further themes in engaging others, enabling and enacting the FYE program that fostered internal mandates for change: gaining buy-in; being opportunistic; making use of evidence of success and recognition; along with the need for collegial support for coordinators and self-perceptions of leadership being about making connections, collaboration, trust and expertise.

  5. Endoscopic variceal band ligation: a local experience | Jani | East ...

    African Journals Online (AJOL)

    Objective: To evaluate the results of endoscopic variceal band ligation (EVBL) in the local set-up. Design: Retrospective analysis of data of all patients who had EVBL. Setting: Patients having EVBL at the office endoscopy suite. The Nairobi Hospital, the Aga Khan Hospital and M.P Shah Hospital. Methods: The varices were ...

  6. Experience of Percutaneous Trigger Finger Release under Local ...

    African Journals Online (AJOL)

    Background: Trigger finger is a common disorder of upper extremity. Majority of the patients can be treated conservatively but some resistant cases eventually need surgery. Aim: The aim of this study is to evaluate the results of percutaneous trigger finger release under local anesthesia. Subjects and Methods: This is a ...

  7. Thyroidectomy under local anaesthesia: experience with giant goitres

    African Journals Online (AJOL)

    Adele

    the thyroid notch and the lower flap down to the suprasternal notch. The investing fascia is then incised ... required in thyroid gland mobilization especially when done under local anaesthesia and traction on the .... Gitau W. An analysis of thyroid diseases seen at Kenyatta Hospital. E. Afr. Med. J. 1975; 52:564-570. 4.

  8. Condensed Matter Nuclear Science

    Science.gov (United States)

    Biberian, Jean-Paul

    2006-02-01

    1. General. A tribute to gene Mallove - the "Genie" reactor / K. Wallace and R. Stringham. An update of LENR for ICCF-11 (short course, 10/31/04) / E. Storms. New physical effects in metal deuterides / P. L. Hagelstein ... [et al.]. Reproducibility, controllability, and optimization of LENR experiments / D. J. Nagel -- 2. Experiments. Electrochemistry. Evidence of electromagnetic radiation from Ni-H systems / S. Focardi ... [et al.]. Superwave reality / I. Dardik. Excess heat in electrolysis experiments at energetics technologies / I. Dardik ... [et al.]. "Excess heat" during electrolysis in platinum/K[symbol]CO[symbol]/nickel light water system / J. Tian ... [et al.]. Innovative procedure for the, in situ, measurement of the resistive thermal coefficient of H(D)/Pd during electrolysis; cross-comparison of new elements detected in the Th-Hg-Pd-D(H) electrolytic cells / F. Celani ... [et al.]. Emergence of a high-temperature superconductivity in hydrogen cycled Pd compounds as an evidence for superstoihiometric H/D sites / A. Lipson ... [et al.]. Plasma electrolysis. Calorimetry of energy-efficient glow discharge - apparatus design and calibration / T. B. Benson and T. O. Passell. Generation of heat and products during plasma electrolysis / T. Mizuno ... [et al.]. Glow discharge. Excess heat production in Pd/D during periodic pulse discharge current in various conditions / A. B. Karabut. Beam experiments. Accelerator experiments and theoretical models for the electron screening effect in metallic environments / A. Huke, K. Czerski, and P. Heide. Evidence for a target-material dependence of the neutron-proton branching ratio in d+d reactions for deuteron energies below 20keV / A. Huke ... [et al.]. Experiments on condensed matter nuclear events in Kobe University / T. Minari ... [et al.]. Electron screening constraints for the cold fusion / K. Czerski, P. Heide, and A. Huke. Cavitation. Low mass 1.6 MHz sonofusion reactor / R. Stringham. Particle detection. Research

  9. Local investment in renewable energies - European experiences; Investissement local dans les energies renouvelables - recueil d'experiences europeennes

    Energy Technology Data Exchange (ETDEWEB)

    Quantin, J; Grepmeier, K; Larsen, J; Manolakaki, E; Smith, M

    2004-01-01

    This booklet is realized within the framework of the european commission called PREDAC. This document have been conceived by a working group specialized on the local investment into renewable energies thematic. The objectives of this project are: to promote citizen participation in the financing of renewable energies projects in Europe; to make organizations, investor clubs and local government to be aware of this way of implication into renewable energies development; to examine more especially three renewable energy sources: biomass, photovoltaic and wind in Denmark, France, Germany, Greece and United Kingdom. (author)

  10. Local investment in renewable energies - European experiences; Investissement local dans les energies renouvelables - recueil d'experiences europeennes

    Energy Technology Data Exchange (ETDEWEB)

    Quantin, J.; Grepmeier, K.; Larsen, J.; Manolakaki, E.; Smith, M

    2004-01-01

    This booklet is realized within the framework of the european commission called PREDAC. This document have been conceived by a working group specialized on the local investment into renewable energies thematic. The objectives of this project are: to promote citizen participation in the financing of renewable energies projects in Europe; to make organizations, investor clubs and local government to be aware of this way of implication into renewable energies development; to examine more especially three renewable energy sources: biomass, photovoltaic and wind in Denmark, France, Germany, Greece and United Kingdom. (author)

  11. Universal Themes of Bose-Einstein Condensation

    Science.gov (United States)

    Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.

    2017-04-01

    -Einstein condensation of photons and grand-canonical condensate fluctuations J. Klaers and M. Weitz; 20. Laser operation and Bose-Einstein condensation: analogies and differences A. Chiocchetta, A. Gambassi and I. Carusotto; 21. Vortices in resonant polariton condensates in semiconductor microcavities D. N. Krizhanovskii, K. Guda, M. Sich, M. S. Skolnick, L. Dominici and D. Sanvitto; 22. Optical control of polariton condensates G. Christmann, P. G. Savvidis and J. J. Baumberg; 23. Disorder, synchronization and phase-locking in non-equilibrium Bose-Einstein condensates P. R. Eastham and B. Rosenow; 24. Collective topological excitations in 1D polariton quantum fluids H. Terças, D. D. Solnyshkov and G. Malpuech; 25. Microscopic theory of Bose-Einstein condensation of magnons at room temperature H. Salman, N. G. Berloff and S. O. Demokritov; 26. Spintronics and magnon Bose-Einstein condensation R. A. Duine, A. Brataas, S. A. Bender and Y. Tserkovnyak; 27. Spin-superfluidity and spin-current mediated non-local transport H. Chen and A. H. MacDonald; 28. Bose-Einstein condensation in quantum magnets C. Kollath, T. Giamarchi and C. Rüegg; Part V. Condensates in Astrophysics and Cosmology: Editorial notes; 29. Bose-Einstein condensates in neutron stars C. J. Pethick, T. Schäfer and A. Schwenk; 30. A simulated cosmological metric: the superfluid 3He condensate G. R. Pickett; 31. Cosmic axion Bose-Einstein condensation N. Banik and P. Sikivie; 32. Graviton BECs: a new approach to quantum gravity G. Dvali and C. Gomez; Universal Bose-Einstein condensation workshop; Index.

  12. Uterine fibroid embolisation: Initial experience in our local population

    International Nuclear Information System (INIS)

    Jawad, R.A.; Rehman, I.; Rana, A.I.; Tariq, N.; Tariq, N.

    2013-01-01

    Objective: To evaluate the results of uterine fibroid embolisation as a treatment option for symptomatic uterine fibroids in the local population. Methods: The retrospective study was done at the Department of Diagnostic and Interventional Radiology, Shifa International Hospital, Islamabad, and comprised records of 12 patients with symptomatic uterine fibroids who had undergone uterine fibroid embolisation with the use of polyvinyl alcohol between May 2008 and July 2012. All of these patients had been assessed by a gynaecologist. Pre-embolisation workup was done by pelvic Magnetic Resonance Imaging. A detailed questionnaire was prepared to assess clinical improvement and interval change in fibroid size on follow-up imaging. Results: A technically successful embolisation was done in all patients. All patients experienced immediate post-procedure pain, but responded to conservative treatment. Clinical follow-up showed a significant reduction in symptoms within six months of the procedure, with 88% improvement in menorrhagia and 100% improvement in pain. Follow-up imaging showed reduction in fibroid sizes ranging from 17-63%. Two patients developed infection, which is a known complication of this procedure. Conclusion: Uterine fibroid embolisation is a well-recognised treatment option for symptomatic uterine fibroids. Ascertaining its long-term results in our local population will, however, require additional studies with larger patient populations. (author)

  13. Recent developments in Bose-Einstein condensation

    International Nuclear Information System (INIS)

    Kalman, G.

    1997-01-01

    This paper contains viewgraphs on developments on Bose-Einstein condensation. Some topics covered are: strongly coupled coulomb systems; standard response functions of the first and second kind; dynamical mean field theory; quasi localized charge approximation; and the main equations

  14. Recent developments in Bose-Einstein condensation

    Energy Technology Data Exchange (ETDEWEB)

    Kalman, G.

    1997-09-22

    This paper contains viewgraphs on developments on Bose-Einstein condensation. Some topics covered are: strongly coupled coulomb systems; standard response functions of the first and second kind; dynamical mean field theory; quasi localized charge approximation; and the main equations.

  15. Performance of evaporative condensers

    Energy Technology Data Exchange (ETDEWEB)

    Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

    2001-07-01

    Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

  16. The experience of a local partnership with experts

    International Nuclear Information System (INIS)

    Draulans, H.

    2004-01-01

    STOLA is an abbreviation for Structured Study group for Low-level short-lived radioactive waste, with all the actors of our small community of Dessel. You may know: social culture and economic factors of course all play a role in radioactive waste management and we work together with the experts of ONDRAF/NIRAS. But I am sure that was explained to you sufficiently yesterday and I can skip all that. 70 000 m 3 of low-level radioactive waste can be disposed of in our area and that only under certain safety conditions for humans and the environment. Of course one of the conditions is also that it has an added value for our municipality. In the past four years, I have participated in the activities of STOLA in Dessel and also led them. In that period, I met many, many experts, I spoke to them; I also really listened to them and together we worked on this disposal process. I will give you my personal opinion on that contact with those experts. Although I am going to be one in a long list of professors giving lectures today, I may not be the most scientific of speakers: I will be talking mainly from my experience with the people from STOLA. (author)

  17. A Preliminary Study of Transverse Curvature Effects on Condensation Heat Transfer on Vertical Tube in the Presence of Non-condensable Gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yeon Gun; Kim, Sin [Jeju National Univ., Jeju (Korea, Republic of); Jerng, Dong Wook [Chung Ang Univ., Seoul (Korea, Republic of)

    2013-10-15

    In this study, the effect of the transverse curvature on the condensation HTC on a vertical tube in the presence of air is preliminarily investigated by using the analysis of boundary layer for free convective heat transfer. The results indicate that the heat transfer performance can be enhanced as the outer diameter of condenser tubes is small. To confirm this curvature effect, an experimental program to obtain the condensation heat transfer data for various values of tube diameter is indispensable. Currently, by a joint research project of Jeju National University and Chung-Ang University, a condensation test facility is being designed and constructed to acquire the condensation HTC data as shown in Fig. 3. From a series of experiment on a single vertical tube, the effects of not only the tube diameter but the inclination, the existence of fins and the local velocity of a bulk mixture by natural circulation will be evaluated precisely. An empirical correlation for the condensation heat transfer of a steam-air mixture will also be developed for design optimization and performance evaluation of the PCCS. The Passive Containment Cooling System (PCCS) provides passive means to remove the decay heat and protect the integrity of the containment during severe accidents. Korea, in which all the NPPs employ the concrete containment, may adopt a PCCS using internal condensers. In the event of the loss-of-coolant accident (LOCA), steam released from the reactor coolant system is mixed with air inside the containment and condensed on the outer surface of inclined condenser tubes. It is noted that, among previous theoretical and empirical models for condensation on outer wall in the presence of non-condensable gas, no one took into account the effect of a tube diameter. Though the condensation heat transfer coefficient may vary with transverse curvature of condenser tubes, such a curvature effect has not been reported so far. In this study, a preliminary analysis is conducted

  18. A Preliminary Study of Transverse Curvature Effects on Condensation Heat Transfer on Vertical Tube in the Presence of Non-condensable Gas

    International Nuclear Information System (INIS)

    Lee, Yeon Gun; Kim, Sin; Jerng, Dong Wook

    2013-01-01

    In this study, the effect of the transverse curvature on the condensation HTC on a vertical tube in the presence of air is preliminarily investigated by using the analysis of boundary layer for free convective heat transfer. The results indicate that the heat transfer performance can be enhanced as the outer diameter of condenser tubes is small. To confirm this curvature effect, an experimental program to obtain the condensation heat transfer data for various values of tube diameter is indispensable. Currently, by a joint research project of Jeju National University and Chung-Ang University, a condensation test facility is being designed and constructed to acquire the condensation HTC data as shown in Fig. 3. From a series of experiment on a single vertical tube, the effects of not only the tube diameter but the inclination, the existence of fins and the local velocity of a bulk mixture by natural circulation will be evaluated precisely. An empirical correlation for the condensation heat transfer of a steam-air mixture will also be developed for design optimization and performance evaluation of the PCCS. The Passive Containment Cooling System (PCCS) provides passive means to remove the decay heat and protect the integrity of the containment during severe accidents. Korea, in which all the NPPs employ the concrete containment, may adopt a PCCS using internal condensers. In the event of the loss-of-coolant accident (LOCA), steam released from the reactor coolant system is mixed with air inside the containment and condensed on the outer surface of inclined condenser tubes. It is noted that, among previous theoretical and empirical models for condensation on outer wall in the presence of non-condensable gas, no one took into account the effect of a tube diameter. Though the condensation heat transfer coefficient may vary with transverse curvature of condenser tubes, such a curvature effect has not been reported so far. In this study, a preliminary analysis is conducted

  19. Experience in organizing and operating of local centers of radiation monitoring in Belarus

    International Nuclear Information System (INIS)

    Nesterenko, V.B.; Devojno, A.N.

    1993-01-01

    The paper analyzes the experience in the arrangement and activity of local centres for the radiation monitoring of foods and of articles of daily use established under the control of the rural and urban area administrations at the contaminated territories. The measurement results obtained by the local centres show the deep contamination of food from the local farms and from the local fields and forests, in particular, milk, ferries and mushrooms. RAPIT information system was established automate the processing and analyse of data from the local centres of the radiation monitoring

  20. Condensation of steam

    International Nuclear Information System (INIS)

    Prisyazhniuk, V.A.

    2002-01-01

    An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

  1. In-Space technology experiments program. A high efficiency thermal interface (using condensation heat transfer) between a 2-phase fluid loop and heatpipe radiator: Experiment definition phase

    Science.gov (United States)

    Pohner, John A.; Dempsey, Brian P.; Herold, Leroy M.

    1990-01-01

    Space Station elements and advanced military spacecraft will require rejection of tens of kilowatts of waste heat. Large space radiators and two-phase heat transport loops will be required. To minimize radiator size and weight, it is critical to minimize the temperature drop between the heat source and sink. Under an Air Force contract, a unique, high-performance heat exchanger is developed for coupling the radiator to the transport loop. Since fluid flow through the heat exchanger is driven by capillary forces which are easily dominated by gravity forces in ground testing, it is necessary to perform microgravity thermal testing to verify the design. This contract consists of an experiment definition phase leading to a preliminary design and cost estimate for a shuttle-based flight experiment of this heat exchanger design. This program will utilize modified hardware from a ground test program for the heat exchanger.

  2. Prior Visual Experience Modulates Learning of Sound Localization Among Blind Individuals.

    Science.gov (United States)

    Tao, Qian; Chan, Chetwyn C H; Luo, Yue-Jia; Li, Jian-Jun; Ting, Kin-Hung; Lu, Zhong-Lin; Whitfield-Gabrieli, Susan; Wang, Jun; Lee, Tatia M C

    2017-05-01

    Cross-modal learning requires the use of information from different sensory modalities. This study investigated how the prior visual experience of late blind individuals could modulate neural processes associated with learning of sound localization. Learning was realized by standardized training on sound localization processing, and experience was investigated by comparing brain activations elicited from a sound localization task in individuals with (late blind, LB) and without (early blind, EB) prior visual experience. After the training, EB showed decreased activation in the precuneus, which was functionally connected to a limbic-multisensory network. In contrast, LB showed the increased activation of the precuneus. A subgroup of LB participants who demonstrated higher visuospatial working memory capabilities (LB-HVM) exhibited an enhanced precuneus-lingual gyrus network. This differential connectivity suggests that visuospatial working memory due to the prior visual experience gained via LB-HVM enhanced learning of sound localization. Active visuospatial navigation processes could have occurred in LB-HVM compared to the retrieval of previously bound information from long-term memory for EB. The precuneus appears to play a crucial role in learning of sound localization, disregarding prior visual experience. Prior visual experience, however, could enhance cross-modal learning by extending binding to the integration of unprocessed information, mediated by the cognitive functions that these experiences develop.

  3. Demonstration of Nautilus Centripetal Capillary Condenser Technology

    Science.gov (United States)

    Wheeler, RIchard; Tang, Linh; Wambolt, Spencer; Golliher, Eric; Agui, Juan

    2016-01-01

    This paper describes the results of a proof of concept effort for development of a Nautilus Centripetal Capillary Condenser (NCCC or NC3) used for microgravity compatible water recovery from moist air with integral passive phase separation. Removal of liquid condensate from the air stream exiting a condenser is readily performed here on Earth. In order to perform this function in space however, without gravity or mechanical action, other tactics including utilization of inertial, drag and capillary forces are required. Within the NC3, liquid water forms via condensation on cold condenser surfaces as humid air passes along multiple spiral channels, each in its own plane, all together forming a stacked plate assembly. Non-mechanical inertial forces are employed to transfer condensate, as it forms, via centripetal action to the outer perimeter of each channel. A V-shaped groove, constructed on this outer edge of the spiral channel, increases local capillary forces thereby retaining the liquid. Air drag then pulls the liquid along to a collection region near the center of the device. Dry air produced by each parallel spiral channel is combined in a common orthogonal, out-of-plane conduit passing down the axial center of the stacked device. Similarly, the parallel condensate streams are combined and removed from the condenser/separator through yet another out-of-plane axial conduit. NC3 is an integration of conventional finned condenser operation, combined with static phase separation and capillary transport phenomena. A Mars' transit mission would be a logical application for this technology where gravity is absent and the use of vibrating, energy-intensive, motor-driven centrifugal separators is undesired. Here a vapor stream from either the Heat Melt Compactor or the Carbon dioxide Reduction Assembly, for example, would be dried to a dew point of 10 deg using a passive NC3 condenser/separator with the precious water condensate recycled to the water bus.

  4. Capillary condensation of adsorbates in porous materials.

    Science.gov (United States)

    Horikawa, Toshihide; Do, D D; Nicholson, D

    2011-11-14

    Hysteresis in capillary condensation is important for the fundamental study and application of porous materials, and yet experiments on porous materials are sometimes difficult to interpret because of the many interactions and complex solid structures involved in the condensation and evaporation processes. Here we make an overview of the significant progress in understanding capillary condensation and hysteresis phenomena in mesopores that have followed from experiment and simulation applied to highly ordered mesoporous materials such as MCM-41 and SBA-15 over the last few decades. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Experimental investigation of reflux condensation heat transfer in PWR steam generator tubes in the presence of noncondensible gases

    Energy Technology Data Exchange (ETDEWEB)

    Vierow, Karen; Wu, Tiejun [Purdue Univ., West Lafayette (United States); Nagae, Takashi [Institute of Nuclear Safety System, Tokyo (Japan)

    2003-07-01

    Under certain circumstances in a Pressurized Water Reactor (PWR), the coolant system may be in a partially drained state and reflux condensation in the steam generator U-tubes can be the major heat removal mechanism. Noncondensable gases may be present and would degrade the heat transfer rate. If heat removal rates are insufficient, this situation could lead to core boil-off, fuel rod heatup, and eventually core damage. The Institute of Nuclear Safety System, Inc. (INSS) and the Nuclear Heat Transfer Systems Laboratory at Purdue University have begun a cooperative research program to investigate the effectiveness of reflux condensation in PWR steam generator U-tubes in the presence of noncondensable gases. The final objectives are to provide local heat transfer data for development of methods to analyze reflux condensation in PWR steam generator U-tubes and to investigate the potential for flooding. Key features of the experimental data reported herein are that they are local data under laminar steam/gas mixture and condensate film flow and they are taken from a test section with dimensions similar to an actual steam generator tube. Steady state data were obtained under various steam and air inlet flow rates and pressures. The data show the significant degrading effect of noncondensable gas on heat transfer coefficients. From the data, correlations for the reflux condensation local heat transfer coefficient and the local Nusselt number under laminar conditions were derived. These experiments are providing essential and unique fundamental data for development of methods to analyze reflux condensation.

  6. Condensation of the steam in the horizontal steam line during cold water flooding

    International Nuclear Information System (INIS)

    Strubelj, L.; Tiselj, I.

    2006-01-01

    Direct contact condensation and condensation induced water-hammer in a horizontal pipe was experimentally investigated at PMK-2 test facility of the Hungarian Atomic Energy Research Institute KFKI. The experiment is preformed in the horizontal section of the steam line of the PMK-2 integral test facility. As liquid water floods the horizontal part of the pipeline, the counter current horizontally stratified flow is being observed. During the flooding of the steam line, the vapour-liquid interface area increases and therefore the vapour condensation rate and the vapour velocity also increase. Similar phenomena can occur in the cold/hot leg of the primary loop of PWR nuclear power plant during loss of coolant accident, when emergency core cooling system is activated. Water level at one cross-section and four local void fraction and temperature at the top of steam line was measured and compared with simulation. Condensed steam increases the water temperature that is why the local temperature measurements are the most important information, from which condensation rate can be estimated, since mass of condensed steam was not measured. Free surface simulation of the experiment with thermal phase change model is presented. Surface renewal concept with small eddies is used for calculation of heat transfer coefficient. With surface renewal theory we did not get results similar to experiment, that is why heat transfer coefficient was increased by factor 20. In simulation with heat transfer coefficient calculated with surface renewal concept bubble entrapment is due to reflection of the wave from the end of the pipe. When heat transfer coefficient is increased, condensation rate and steam velocity are also increased, bubble entrapment is due to Kelvin-Helmholtz instability of the free surface, and the results become similar to the measurements. (author)

  7. A Solid-State NMR Experiment: Analysis of Local Structural Environments in Phosphate Glasses

    Science.gov (United States)

    Anderson, Stanley E.; Saiki, David; Eckert, Hellmut; Meise-Gresch, Karin

    2004-01-01

    An experiment that can be used to directly study the local chemical environments of phosphorus in solid amorphous materials is demonstrated. The experiment aims at familiarizing the students of chemistry with the principles of solid-state NMR, by having them synthesize a simple phosphate glass, and making them observe the (super 31)P NMR spectrum,…

  8. Event-based computer simulation model of aspect-type experiments strictly satisfying Einstein's locality conditions

    NARCIS (Netherlands)

    De Raedt, Hans; De Raedt, Koen; Michielsen, Kristel; Keimpema, Koenraad; Miyashita, Seiji

    2007-01-01

    Inspired by Einstein-Podolsky-Rosen-Bohtn experiments with photons, we construct an event-based simulation model in which every essential element in the ideal experiment has a counterpart. The model satisfies Einstein's criterion of local causality and does not rely on concepts of quantum and

  9. Characteristic aspects of pion-condensed phases

    International Nuclear Information System (INIS)

    Takatsuka, Tatsuyuki; Tamagaki, Ryozo; Tatsumi, Toshitaka.

    1993-01-01

    Characteristic aspects of pion-condensed phases are described in a simple model, for the system involving only nucleons and pions which interact through the π-N P-wave interaction. We consider one typical version in each of three kinds of pion condensation; the one of neutral pions (π 0 ), the one of charged pions (π C ) and the combined one in which both the π 0 and π C condensations are coexistent. Emphasis is put on the description to clarify the novel structures of the nucleon system which are realized in the pion-condensed phases. At first, it is shown that the π 0 condensation is equivalent to the particular nucleonic phase realized by a structure change of the nucleon system, where the attractive first-order effect of the one-pion-exchange (OPE) tensor force is brought about coherently. The aspects of this phase are characterized by the layered structure with a specific spin-isospin order with one-dimensional localization (named the ALS structure in short), which provides the source function for the condensed π 0 field. We utilize both descriptions with use of fields and potentials for the π 0 condensation. Next, the π C condensation realized in neutron-rich matter is described by adopting a version of the traveling condensed wave. In this phase, the nucleonic structure becomes the Fermi gas consisting of quasi-neutrons described by a superposition of neutron and proton. In this sense the structure change of the nucleon system for the π C condensation is moderate, and the field description is suitable. Finally, we describe a coexistent pion condensation, in which both the π 0 and π C condensations coexist without interference in such a manner that the π C condensation develops in the ALS structure. The model adopted here provides us with the characteristic aspects of the pion-condensed phases persisting in the realistic situation, where other ingredients affecting the pion condensation are taken into account. (author)

  10. Condensate cleaning systems

    International Nuclear Information System (INIS)

    Yamamoto, Michiyoshi; Oosumi, Katsumi; Takashima, Yoshie; Mitani, Shinji.

    1982-01-01

    Purpose: To decrease the frequency for the backwash and regeneration operations due to the increase in the differential pressure resulted from claddings captured in a mixed floor type desalter, and decrease the amount of radioactive liquid wastes of claddings from the condensate systems by removing claddings with electromagnetic filters. Constitution: In an existent plant, a valves is disposed between a condensate pump and a mixed floor type desalter. A pipeway is branched from a condensate pipe between the condensate pipe and the valve, through which condensates are transferred by a pump to an electromagnetic filter such as of a high gradient type electromagntic filter to remove claddings, then returned to a condensate pipe between the valve and the mixed floor type desalter and, thereafter, are removed with ionic components in the mixed floor type desalter and fed to the reactor. (Yoshino, Y.)

  11. Purification method for condensate

    International Nuclear Information System (INIS)

    Shimoda, Akiyoshi.

    1996-01-01

    Condensates generated in secondary coolant circuits of a PWR type reactor are filtered using a hollow thread separation membranes comprising aromatic polyether ketone. Preferably, condensates after passing through a turbine are filtered at a place between a condensator and a steam generator at high temperature as close as a temperature of the steam generator. As the hollow thread membrane, partially crystalline membrane comprising aromatic polyether ketone is used. When it is used at high temperature, the crystallinity is preferably not less than 15wt%. Since a hollow thread membrane comprising the aromatic polyether ketone of excellent heat resistance is used, it can filter and purify the condensates at not lower than 70degC. Accordingly, impurities such as colloidal iron can be removed from the condensates, and the precipitation of cruds in the condensates to a steam generator and a turbine can be suppressed. (I.N.)

  12. Quark virtuality and QCD vacuum condensates

    International Nuclear Information System (INIS)

    Zhou Lijuan; Ma Weixing

    2004-01-01

    Based on the Dyson-Schwinger equations (DSEs) in the 'rainbow' approximation, the authors investigate the quark virtuality in the vacuum state and quantum-chromodynamics (QCD) vacuum condensates. In particular, authors calculate the local quark vacuum condensate and quark-gluon mixed condensates, and then the virtuality of quark. The calculated quark virtualities are λ u,d 2 =0.7 GeV 2 for u, d quarks, and λ s 2 =1.6 GeV 2 for s quark. The theoretical predictions are consistent with empirical values used in QCD sum rules, and also fit to lattice QCD predictions

  13. LMFBR operational and experimental local-fault experience, primarily with oxide fuel elements

    International Nuclear Information System (INIS)

    Warinner, D.K.

    1980-01-01

    Case-by-case reviews of selective world experience with severe local faults, particularly fuel failure and fuel degradation, are reviewed for two sodium-cooled thermal reactors, several LMFBRs, and LMFBR-fuels experiments. The review summarizes fuel-failure frequency and illustrates the results of the most damaging LMFBR local-fault experiences of the last 20 years beginning with BR-5 and including DFR, BOR-60, BR2's MFBS- and Mol-loops experiments, Fermi, KNK, Rapsodie, EBR-II, and TREAT-D2. Local-fault accommodation is demonstrated and a need to more thoroughly investigate delayed-neutron and gaseous-fission-product signals is highlighted in view of uranate formation, observed blockages, and slow fuel-element failure-propagation

  14. LMFBR operational and experimental in-core local-fault experience, primarily with oxide fuel elements

    International Nuclear Information System (INIS)

    Warinner, D.K.

    Case-by-case reviews of selective world experience with severe local faults, particularly fuel failure and fuel degradation, are reviewed for two sodium-cooled thermal reactors, several LMFBRs, and LMFBR-fuels experiments. The review summarizes fuel-failure frequency and illustrates the results of the most damaging LMFBR local-fault experiences of the last 20 years beginning with BR-5 and including DFR, BOR-60, BR2's MFBS-and Mol-loops experiments, Fermi, KNK, Rapsodie, EBR-II, and TREAT-D2. Local-fault accommodation is demonstrated and a need to more thoroughly investigate delayed-neutron and gaseous-fission-product signals is highlighted in view of uranate formation, observed blockages, and slow fuel-element failure-propagation

  15. Imbibition Triggered by Capillary Condensation in Nanopores.

    Science.gov (United States)

    Vincent, Olivier; Marguet, Bastien; Stroock, Abraham D

    2017-02-21

    We study the spatiotemporal dynamics of water uptake by capillary condensation from unsaturated vapor in mesoporous silicon layers (pore radius r p ≃ 2 nm), taking advantage of the local changes in optical reflectance as a function of water saturation. Our experiments elucidate two qualitatively different regimes as a function of the imposed external vapor pressure: at low vapor pressures, equilibration occurs via a diffusion-like process; at high vapor pressures, an imbibition-like wetting front results in fast equilibration toward a fully saturated sample. We show that the imbibition dynamics can be described by a modified Lucas-Washburn equation that takes into account the liquid stresses implied by Kelvin equation.

  16. Improving students’ creative thinking skill through local material-based experiment (LMBE) on protein qualitative test

    Science.gov (United States)

    Supriyanti, F. M. T.; Halimatul, H. S.

    2018-05-01

    This study aims to enhance chemistry students’ creative thinking skills using material from local resources on protein qualitative test experiment (LMBE). In this study, a quasi experiment method using one group pretest-postest non-equivalen control group design was carried out on the effectiveness of local material-based experiment approach. The data was collected using the test consists of five assay test and student work sheet (LKM). The effectiveness of the local material-based experiment was tested by means of percentage of normalized gain and score percentage of students’ worksheet. Comparison of creative thinking skills pretest and postest scores showed that the implementation of local material- based experiment (LMBE) enhanced students’s creative thinking skills in experiment class with the value of normalized gain (=0,77) at high category, while in control class reached to =0,44 at medium category. In addition, the LKM shown the enhancements of all aspect of creative thinking skills, including fluency, flexibility, and elaboration skills with the score of in experiment class are 0.79; 0.75; and 0.87 at high category, respectively. In contrast, the only the elaboration skill of control group was improved at high category (=0.76), while fluency and flexibility indicators enhanced at medium category (=0.48 and 0.56, respectively).

  17. Comprehensive and consistent interpretation of local fault experiments and application to hypothetical local overpower accident in Monju

    International Nuclear Information System (INIS)

    Fukano, Yoshitaka

    2013-01-01

    Experimental studies on local fault (LF) accidents in fast breeder reactors have been performed in many countries because LFs have been historically considered as one of the possible causes of severe accidents. Comprehensive and consistent interpretations of in-pile and out-of-pile experiments related to LF were arrived at in this study based on state-of-the-art review and data analysis techniques. Safety margins for a hypothetical local overpower accident, which was evaluated as a LF accident in the licensing document of the construction permit for a prototype fast breeder reactor called Monju, were also studied. Based on comprehensive interpretations of the latest experimental database, including those performed after the permission of Monju construction, it was clarified that the evaluation of the hypothetical local overpower accident in the Monju licensing was sufficiently conservative. Furthermore, it incorporated adequate safety margins in terms of failure thresholds of the fuel pin, molten fuel ejection, fuel sweep-out behavior after molten fuel ejection, and pin-to-pin failure propagation. Moreover, these comprehensive interpretations are valid and applicable to the safety evaluation of LF accidents of other fast breeder reactors with various fuel and core designs. (author)

  18. Systematic text condensation

    DEFF Research Database (Denmark)

    Malterud, Kirsti

    2012-01-01

    To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies.......To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies....

  19. Building local competences to meet mining activities – strategies based on experiences from Greenland and Island

    DEFF Research Database (Denmark)

    Jørgensen, Ulrik; Gjedssø Bertelsen, Rasmus; Hendriksen, Kåre

    Mineral extraction in the Arctic is seen as a key to overcome future shortages of raw materials and local economic challenges in northern regions. Governmental strategies aim at building competence in governance and a local workforce that can be employed in mining industries and related businesses....... However many mining companies envisage potentials for a fast extraction of the resources using immigrant and migrant laborers that work intensively over a period of time while living in shantytowns. Past Greenland experiences with this type of work organization is not particularly positive. Experiences...... predominantly been based of norms and practices handled by international consultants and the specific topics lack important impacts related to the speed of economic exploitation and the options for social and educational development for the local population. International experiences also demonstrate...

  20. Bell-type experiments and the concept of locally stochastic causality

    International Nuclear Information System (INIS)

    Andaas, H.E.

    1992-08-01

    The concept of locally stochastic causality (LSC), related to the theory of local beables suggested by Bell, is introduced. It is argued that the experiments performed to verify the predictions of Bell's inequalities have merely been tests for the possibility of a description of nature in terms of joint probability distributions for the observables and that they do not provide sufficient results to sustain claims that theories based upon LSC have been falsified. 31 refs., 5 figs

  1. Local agenda 21. The French experience; Agendas 21 locaux. L'experience francaise

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    In keeping with the Rio Declaration on Environment and Development, and with the ''Agenda 21'' Action program for the 21 Century, the French Minister of the Environment, in January 1993, and again on 11 May 1994, set up new mechanisms, entitled ''Urban Ecology Charters'' or ''Environmental Charters'', also described as ''Partnership Programmes for Sustainable Development''. Their purpose is to implement a new economic approach which, in the Rio spirit, encourages a sustainable form of development, characterized by the integration of environmental costs. Since 1999, a broad new legal text, the ''Act on Spatial Planning and Sustainable Development Policy'' encourages urban and rural local government to define and run development projects that refer to Chapter 28 of the Action 21 program of Rio. The development of Agenda 21 is now supported by contracts between the State and local authorities of various character, such as the large ''Regions'' (of which there are only 21 in France), local institutions responsible for managing urban agglomerations, smaller ad-hoc rural areas called ''Pays'', and some of the regional natural parks or reserves. Such development projects are required broadly to call upon the participation of, and partnership with concerned private and public stakeholders. They must support modes of production and consumption that are thrifty in resources (energy, water, soil, air, biodiversity), and also socially responsible towards populations of other countries and future generations. (author)

  2. Direct contact condensation in packed beds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi; Klausner, James F.; Mei, Renwei; Knight, Jessica [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2006-12-15

    A diffusion driven desalination process was recently described where a very effective direct contact condenser with a packed bed is used to condense water vapor out of an air/vapor mixture. A laboratory scale direct contact condenser has been fabricated as a twin tower structure with two stages, co-current and countercurrent. Experiments have been operated in each stage with respective saturated air inlet temperatures of 36, 40 and 43{sup o}C. The temperature and humidity data have been collected at the inlet and exit of the packed bed for different water to air mass flow ratios that vary between 0 and 2.5. A one-dimensional model based on conservation principles has been developed, which predicts the variation of temperature, humidity, and condensation rate through the condenser stages. Agreement between the model and experiments is very good. It is observed that the countercurrent flow stage condensation effectiveness is significantly higher than that for the co-current stage. The condensation heat and mass transfer rates were found to decrease when water blockages occur within the packed bed. Using high-speed digital cinematography, it was observed that this problem can occur at any operating condition, and is dependent on the packing surface wetting characteristics. This observation is used to explain the requirement for two different empirical constants, depending on packing diameter, suggested by Onda for the air side mass transfer coefficient correlation. (author)

  3. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Viegas-Pequignot, E.M.

    1981-01-01

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs [fr

  4. Condensation in complex geometries

    International Nuclear Information System (INIS)

    Lauro, F.

    1975-01-01

    A mathematical evaluation of the condensation exchange coefficient can only succeds for well specified cases: small upright or inclined plates, horizontal tubes, small height vertical tubes. Among the main hypotheses accounted for this mathematical development in the case of the condensate, a laminar flow and uniform surface temperature are always considered. In practice certain shapes of surfaces significantly increase the heat transfer during the vapor condensation on a surface wet by the condensate. Such surfaces are rough surfaces such as the condensate is submitted to surface tension effects, negligeable for plane or large curvature surfaces, and the nature of the material may play an important role (temperature gradients). Results from tests on tubes with special shapes, performed in France or out of France, are given [fr

  5. Planning experience and prospects of local participation in implementation of nuclear power in Bangladesh

    International Nuclear Information System (INIS)

    Rahman, M.A.; Islam, A.B.M.N.; Quaiyum, M.A.; Hasnat, K.A.; Hossain, M.

    1983-01-01

    The paper summarizes the overall experience of Bangladesh in planning for the introduction of its nuclear power programme. The basis for selection of the type of contract for the first nuclear power project of the country is explained. The paper then analyses the prospect of local participation in the construction of the first nuclear power station by detailing the local capabilities in fields such as civil works, civil works materials supply, electrical/mechanical supplies, mechanical fabrication/erection, transportation, etc. After analysing the domestic infrastructure, the problem areas are identified and measures necessary to improve the degree of local participation are described. (author)

  6. Modeling of Kerena Emergency Condenser

    Science.gov (United States)

    Bryk, Rafał; Schmidt, Holger; Mull, Thomas; Wagner, Thomas; Ganzmann, Ingo; Herbst, Oliver

    2017-12-01

    KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA) was built in Karlstein, Germany. The emergency condenser (EC) system transfers heat from the reactor pressure vessel (RPV) to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA). The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

  7. Modeling of Kerena Emergency Condenser

    Directory of Open Access Journals (Sweden)

    Bryk Rafał

    2017-12-01

    Full Text Available KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA was built in Karlstein, Germany. The emergency condenser (EC system transfers heat from the reactor pressure vessel (RPV to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA. The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

  8. The Role of Musical Experience in Hemispheric Lateralization of Global and Local Auditory Processing.

    Science.gov (United States)

    Black, Emily; Stevenson, Jennifer L; Bish, Joel P

    2017-08-01

    The global precedence effect is a phenomenon in which global aspects of visual and auditory stimuli are processed before local aspects. Individuals with musical experience perform better on all aspects of auditory tasks compared with individuals with less musical experience. The hemispheric lateralization of this auditory processing is less well-defined. The present study aimed to replicate the global precedence effect with auditory stimuli and to explore the lateralization of global and local auditory processing in individuals with differing levels of musical experience. A total of 38 college students completed an auditory-directed attention task while electroencephalography was recorded. Individuals with low musical experience responded significantly faster and more accurately in global trials than in local trials regardless of condition, and significantly faster and more accurately when pitches traveled in the same direction (compatible condition) than when pitches traveled in two different directions (incompatible condition) consistent with a global precedence effect. In contrast, individuals with high musical experience showed less of a global precedence effect with regards to accuracy, but not in terms of reaction time, suggesting an increased ability to overcome global bias. Further, a difference in P300 latency between hemispheres was observed. These findings provide a preliminary neurological framework for auditory processing of individuals with differing degrees of musical experience.

  9. Sedimentary condensation and authigenesis

    Science.gov (United States)

    Föllmi, Karl

    2016-04-01

    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  10. Bi-Polaron Condensation in High Tc Superconductors

    International Nuclear Information System (INIS)

    Ranninger, J.

    1995-01-01

    On the basis of optical measurements-, photoemission-, EXAFS- and neutron scattering-experiments we conclude that itinerant valence electrons coexist with localized bi-polarons.Entering the metallic phase upon chemical doping, a charge transfer between the two electronic subsystems is triggered off. We show that as the temperature is lowered towards Tc this process leads to a delocalization of bi-polarons due to a precursor effect of superfluidity of those bi-polarons. Upon entering the superconducting phase, these bipolarons ultimately condense into a superfluid state which is expected to largely determine the superconducting properties of high Tc materials. (authors)

  11. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    It is always exciting when developments in one branch of physics turn out to have relevance in a quite different branch. It would be hard to find two branches farther apart in terms of energy scales than early-universe cosmology and low-temperature condensed matter physics. Nevertheless ideas about the formation of topological defects during rapid phase transitions that originated in the context of the very early universe have proved remarkably fruitful when applied to a variety of condensed matter systems. The mathematical frameworks for describing these systems can be very similar. This interconnection has led to a deeper understanding of the phenomena in condensed matter systems utilizing ideas from cosmology. At the same time, one can view these condensed matter analogues as providing, at least in a limited sense, experimental access to the phenomena of the early universe for which no direct probe is possible. As this special issue well illustrates, this remains a dynamic and exciting field. The basic idea is that when a system goes through a rapid symmetry-breaking phase transition from a symmetric phase into one with spontaneously broken symmetry, the order parameter may make different choices in different regions, creating domains that when they meet can trap defects. The scale of those domains, and hence the density of defects, is constrained by the rate at which the system goes through the transition and the speed with which order parameter information propagates. This is what has come to be known as the Kibble-Zurek mechanism. The resultant scaling laws have now been tested in a considerable variety of different systems. The earliest experiments illustrating the analogy between cosmology and condensed matter were in liquid crystals, in particular on the isotropic-to-nematic transition, primarily because it is very easy to induce the phase transition (typically at room temperature) and to image precisely what is going on. This field remains one of the

  12. Physics of condensed matter

    CERN Document Server

    Misra, Prasanta K

    2012-01-01

    Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

  13. Study of local seismic events in Lithuania and adjacent areas using data from the PASSEQ experiment

    Czech Academy of Sciences Publication Activity Database

    Janutyte, I.; Kozlovskaya, E.; Motuza, G.; Plomerová, Jaroslava; Babuška, Vladislav; Gaždová, Renata; Jedlička, Petr; Kolínský, Petr; Málek, Jiří; Novotný, Oldřich; Růžek, Bohuslav

    2013-01-01

    Roč. 170, č. 5 (2013), s. 797-814 ISSN 0033-4553 Institutional support: RVO:67985530 ; RVO:67985891 Keywords : location of local seismic events * East European Craton * PASSEQ passive seismic experiment Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.854, year: 2013

  14. Developing Evidence for Action on the Postgraduate Experience: An Effective Local Instrument to Move beyond Benchmarking

    Science.gov (United States)

    Sampson, K. A.; Johnston, L.; Comer, K.; Brogt, E.

    2016-01-01

    Summative and benchmarking surveys to measure the postgraduate student research experience are well reported in the literature. While useful, we argue that local instruments that provide formative resources with an academic development focus are also required. If higher education institutions are to move beyond the identification of issues and…

  15. Modelling of local/global architectures for second level trigger at the LHC experiment

    International Nuclear Information System (INIS)

    Hajduk, Z.; Iwanski, W.; Korecyl, K.; Strong, J.

    1994-01-01

    Different architectures of the second level triggering system for experiments on LHC have been simulated. The basic scheme was local/global system with distributed computing power. As a tool the authors have used the object-oriented MODSIM II language

  16. Holography, Gravity and Condensed Matter

    Energy Technology Data Exchange (ETDEWEB)

    Hartnoll, Sean [Stanford Univ., CA (United States). Dept. of Physics

    2017-12-20

    Over the five years of funding from this grant, I produced 26 publications. These include a book-long monograph on "Holographic Quantum Matter" that is currently in press with MIT press. The remainder were mostly published in Physical Review Letters, the Journal of High Energy Physics, Nature Physics, Classical and Quantum Gravity and Physical Review B. Over this period, the field of holography applied to condensed matter physics developed from a promising theoretical approach to a mature conceptual and practical edifice, whose ideas were realized in experiments. My own work played a central role in this development. In particular, in the final year of this grant, I co-authored two experimental papers in which ideas that I had developed in earlier years were shown to usefully describe transport in strongly correlated materials — these papers were published in Science and in the Proceedings of the National Academy of Sciences (obviously my contribution to these papers was theoretical). My theoretical work in this period developed several new directions of research that have proven to be influential. These include (i) The construction of highly inhomogeneous black hole event horizons, realizing disordered fixed points and describing new regimes of classical gravity, (ii) The conjecture of a bound on diffusivities that could underpin transport in strongly interacting media — an idea which may be proven in the near future and has turned out to be intimately connected to studies of quantum chaos in black holes and strongly correlated media, (iii) The characterization of new forms of hydrodynamic transport, e.g. with phase-disordered order parameters. These studies pertain to key open questions in our understanding of how non-quasiparticle, intrinsically strongly interacting systems can behave. In addition to the interface between holography and strongly interacting condensed matter systems, I made several advances on understanding the role of entanglement in quantum

  17. Inequality measures perform differently in global and local assessments: An exploratory computational experiment

    Science.gov (United States)

    Chiang, Yen-Sheng

    2015-11-01

    Inequality measures are widely used in both the academia and public media to help us understand how incomes and wealth are distributed. They can be used to assess the distribution of a whole society-global inequality-as well as inequality of actors' referent networks-local inequality. How different is local inequality from global inequality? Formalizing the structure of reference groups as a network, the paper conducted a computational experiment to see how the structure of complex networks influences the difference between global and local inequality assessed by a selection of inequality measures. It was found that local inequality tends to be higher than global inequality when population size is large; network is dense and heterophilously assorted, and income distribution is less dispersed. The implications of the simulation findings are discussed.

  18. Application of local computer networks in nuclear-physical experiments and technology

    International Nuclear Information System (INIS)

    Foteev, V.A.

    1986-01-01

    The bases of construction, comparative performance and potentialities of local computer networks with respect to their application in physical experiments are considered. The principle of operation of local networks is shown on the basis of the Ethernet network and the results of analysis of their operating performance are given. The examples of operating local networks in the area of nuclear-physics research and nuclear technology are presented as follows: networks of Japan Atomic Energy Research Institute, California University and Los Alamos National Laboratory, network realization according to the DECnet and Fast-bus programs, home network configurations of the USSR Academy of Sciences and JINR Neutron Physical Laboratory etc. It is shown that local networks allows significantly raise productivity in the sphere of data processing

  19. Condensation in Microchannels

    National Research Council Canada - National Science Library

    Ameel, Timothy

    1999-01-01

    .... Evaporators and condensers for meso-scale energy systems will most likely be constructed of microchannels due to the microfabrication constraints that limit most structures to two-dimensional planar geometries...

  20. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

    Kakac, S.

    1991-01-01

    This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

  1. Molecular equilibrium with condensation

    International Nuclear Information System (INIS)

    Sharp, C.M.; Huebner, W.F.

    1990-01-01

    Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

  2. SLAC synchronous condenser

    International Nuclear Information System (INIS)

    Corvin, C.

    1995-06-01

    A synchronous condenser is a synchronous machine that generates reactive power that leads real power by 90 degrees in phase. The leading reactive power generated by the condenser offsets or cancels the normal lagging reactive power consumed by inductive and nonlinear loads at the accelerator complex. The quality of SLAC's utility power is improved with the addition of the condenser. The inertia of the condenser's 35,000 pound rotor damps and smoothes voltage excursions on two 12 kilovolt master substation buses, improving voltage regulation site wide. The condenser absorbs high frequency transients and noise in effect ''scrubbing'' the electric system power at its primary distribution source. In addition, the condenser produces a substantial savings in power costs. Federal and investor owned utilities that supply electric power to SLAC levy a monthly penalty for lagging reactive power delivered to the site. For the 1993 fiscal year this totaled over $285,000 in added costs for the year. By generating leading reactive power on site, thereby reducing total lagging reactive power requirements, a substantial savings in electric utility bills is achieved. Actual savings of $150,000 or more a year are possible depending on experimental operations

  3. 20 years of local ecological public health: the experience of Sandwell in the English West Midlands.

    Science.gov (United States)

    Middleton, J; Saunders, P

    2015-10-01

    A long-term picture of the economy and living conditions of Sandwell, an area of England's industrial Midlands, is presented to explore how these underpin and influence its 'health economy'. Sandwell's experience illustrates how public health actors have to tackle industrial and other factors which shape human health. The paper explores how the ecological public health perspective has helped inform the modern public health task in an area such as Sandwell. Some lessons are offered, including: the need to understand the specific economic legacy of a local area (in Sandwell, principally one of polluting and then declining manufacturing industries); the continuing story of infection control; the complexity of tackling poor diet; and the importance of the built environment and town planning. Faced by such challenges, local public health action represents, in effect, an attempt to transcend unecological public health. This can be exciting, innovative and ultimately successful; but it also means being prepared to face daunting and politically charged obstacles and superior national or international forces over which local public health practitioners conventionally have little leverage. The paper argues that, in such unequal power circumstances, public health practitioners have to draw on the creativity within the local population and build a facilitative alliance of formal and informal pro-public health actors. Despite the confounding odds and ever-present stretched resources, the Sandwell experience gives grounds for optimism, being a story of constant creativity and effective local alliances. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  4. Factors Constraining Local Food Crop Production in Indonesia: Experiences from Kulon Progo Regency, Yogyakarta Special Province

    Directory of Open Access Journals (Sweden)

    RADEN RIJANTA

    2013-01-01

    Full Text Available Local food crops are believed to be important alternatives in facing the problems of continuously growing price of food stuff worldwide. There has been a strong bias in national agricultural development policy towards the production of rice as staple food in Indonesia. Local food crops have been neglected in the agricultural development policy in the last 50 years, leading to the dependency on imported commodities and creating a vulnerability in the national food security. This paper aims at assessing the factors constraining local food production in Indonesia based on empirical experiences drawn from a research in Kulon Progo Regency, Yogyakarta Province. The government of Kulon Progo Regency has declared its commitment in the development of local food commodities as a part of its agricultural development policy, as it is mentioned in the long-term and medium-term development planning documents. There is also a head regency decree mandating the use of local food commodities in any official events organized by the government organisations. The research shows that there are at least six policy-related problems and nine technical factors constraining local food crops production in the regency. Some of the policy-related and structural factors hampering the production of local food crops consist of (1 long-term policy biases towards rice, (2 strong biases on rice diet in the community, (3 difficulties in linking policy to practices, (4 lack of information on availability of local food crops across the regency and (5 external threat from the readily available instant food on local market and (6 past contra-productive policy to the production of local food crops. The technical factors constraining local food production comprises (1 inferiority of the food stuff versus the instantly prepared food, (2 difficulty in preparation and risk of contagion of some crops, lack of technology for processing, (3 continuity of supply (some crops are seasonally

  5. local

    Directory of Open Access Journals (Sweden)

    Abílio Amiguinho

    2005-01-01

    Full Text Available The process of socio-educational territorialisation in rural contexts is the topic of this text. The theme corresponds to a challenge to address it having as main axis of discussion either the problem of social exclusion or that of local development. The reasons to locate the discussion in this last field of analysis are discussed in the first part of the text. Theoretical and political reasons are there articulated because the question is about projects whose intentions and practices call for the political both in the theoretical debate and in the choices that anticipate intervention. From research conducted for several years, I use contributions that aim at discuss and enlighten how school can be a potential locus of local development. Its identification and recognition as local institution (either because of those that work and live in it or because of those that act in the surrounding context are crucial steps to progressively constitute school as a partner for development. The promotion of the local values and roots, the reconstruction of socio-personal and local identities, the production of sociabilities and the equation and solution of shared problems were the dimensions of a socio-educative intervention, markedly globalising. This scenario, as it is argued, was also, intentionally, one of transformation and of deliberate change of school and of the administration of the educative territoires.

  6. Percutaneous vertebroplasty under local anaesthesia: feasibility regarding patients' experience

    Energy Technology Data Exchange (ETDEWEB)

    Bonnard, Eric; Foti, Pauline; Amoretti, Nicolas [Nice University Hospital, Diagnostic and Interventional Radiology Unit, Nice (France); Kastler, Adrian [Grenoble University Hospital, Neuroradiology and MRI Unit, CLUNI, Grenoble (France)

    2017-04-15

    Evaluate patients' intraoperative experience of percutaneous vertebroplasty (PV) performed without general anaesthesia in order to assess the feasibility of local anaesthesia and simple analgesic medication as pain control protocol. Ninety-five patients who underwent single-site PV were consecutively included in the study between 2011 and 2013. Each procedure was achieved under local anaesthesia and perfusion of paracetamol, tramadol and dolasetron, with combined CT and fluoroscopy guidance. Numeric pain scale (NPS) was collected before, during and after intervention. After intervention, patients were asked to evaluate their experience as ''very bad'', ''bad'', ''fair'', ''good'' or ''very good'', independently of the pain. Indications for vertebroplasty were osteopenic fractures (78 %), aggressive angiomas (13 %) and somatic tumours (9 %). In 76 % of cases, patients' experience was described as ''very good'' (44 %) or ''good'' (32 %), whereas 19 % described it as ''fair'' and 5 % as ''very bad''. Mean operative NPS was 5.5. After intervention, NPS was significantly lower with a decrease of 4.5 points. No differences were found according to the localization, type of lesion, age or sex either in terms of experience or NPS. Percutaneous vertebroplasty is feasible under local anaesthesia alone, with a very good or good experience in 76 % of the patients. (orig.)

  7. Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Su [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Hong, Soon-Joon, E-mail: sjhong90@fnctech.com [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Park, Ju-Yeop; Seul, Kwang-Won [Korea Institute of Nuclear Safety, 19 Kuseong-dong, Yuseong-gu, Daejon (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer This study collected 11 horizontal in-tube condensation models for stratified flow. Black-Right-Pointing-Pointer This study assessed the predictive capability of the models for steam condensation. Black-Right-Pointing-Pointer Purdue-PCCS experiments were simulated using MARS code incorporated with models. Black-Right-Pointing-Pointer Cavallini et al. (2006) model predicts well the data for stratified flow condition. Black-Right-Pointing-Pointer Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

  8. Development of balanced downflow type surface condensers, (2)

    International Nuclear Information System (INIS)

    Tomida, Akira; Oshima, Yoshikuni; Okochi, Isao; Izumi, Kenkichi.

    1976-01-01

    As the size of the condensers for power generation plants grew large, the new balanced downflow type condenser was developed and completed on the basis of the experiment on steam flow according to the two-dimensional flow model, the analysis of the performance in a tube nest with a computer, and the studies on the effect of outside liquid film and the reheating deaeration of condensate. When the balanced downflow type condensers were adopted for actual plants, the construction, strength and production method were examined, and the reliability of the new condenser was confirmed by the thermal characteristic experiment with the model similar to the actual machine. The condenser comprises a condenser body, supporting plates, cooling tubes, tube plates, water chambers, and reinforcements, and the cooling tubes are arranged so as to exchange heat effectively. The arrangement of tubes is divided into three regions, namely radiation portion, densely arranged portion, and air cooling portion. In the balanced downflow type condensers, the dilution by utilizing condensate is provided against ammonia attack. The apparatuses for the thermal characteristic experiment and the experimental results, and the results of the performance test on the actual balanced downflow type condenser are reported. (Kako, I.)

  9. The modelling of wall condensation with noncondensable gases for the containment codes

    Energy Technology Data Exchange (ETDEWEB)

    Leduc, C.; Coste, P.; Barthel, V.; Deslandes, H. [Commissariat a l`Energi Atomique, Grenoble (France)

    1995-09-01

    This paper presents several approaches in the modelling of wall condensation in the presence of noncondensable gases for containment codes. The lumped-parameter modelling and the local modelling by 3-D codes are discussed. Containment analysis codes should be able to predict the spatial distributions of steam, air, and hydrogen as well as the efficiency of cooling by wall condensation in both natural convection and forced convection situations. 3-D calculations with a turbulent diffusion modelling are necessary since the diffusion controls the local condensation whereas the wall condensation may redistribute the air and hydrogen mass in the containment. A fine mesh modelling of film condensation in forced convection has been in the developed taking into account the influence of the suction velocity at the liquid-gas interface. It is associated with the 3-D model of the TRIO code for the gas mixture where a k-{xi} turbulence model is used. The predictions are compared to the Huhtiniemi`s experimental data. The modelling of condensation in natural convection or mixed convection is more complex. As no universal velocity and temperature profile exist for such boundary layers, a very fine nodalization is necessary. More simple models integrate equations over the boundary layer thickness, using the heat and mass transfer analogy. The model predictions are compared with a MIT experiment. For the containment compartments a two node model is proposed using the lumped parameter approach. Heat and mass transfer coefficients are tested on separate effect tests and containment experiments. The CATHARE code has been adapted to perform such calculations and shows a reasonable agreement with data.

  10. Modelling of film condensation in presence of non condensable gases

    International Nuclear Information System (INIS)

    Genevieve Geffraye; Dominique Bestion; Vladimir Kalitvianski

    2005-01-01

    Full text of publication follows: This paper presents recent developments in the modelling of the condensation due to heat removal from a wall with a possible presence of hydrogen, nitrogen, or air. This work is mainly concerned with nuclear reactor safety with particular reference to situations related to new reactor design, cold shutdown state and severe accident analysis. Film condensation of steam in presence of nitrogen and helium in a tube has been investigated in the COTURNE experiment in a rather large range of parameters, pressure (from 0.1 to 7 Mpa), heat flux (0.1 to 6 W/cm 2 ), mass fraction of noncondensable gas (0 to 1) and also in presence of superheated steam. The experiment represents a Steam Generator tube of a Pressurised Water Reactor and can simulate both co-current or countercurrent flow of steam and water.The models are implemented in the CATHARE code used for nuclear reactor thermal-hydraulics. The code uses two mass balance equations for liquid and gas, two momentum balance equations for liquid and gas and two energy balance equations for liquid and gas. Additional mass transport equations can be added for each non condensable gas. Heat transfers from wall to liquid film, from liquid to interface and gas to interface are modelled. The liquid film heat transfer coefficient is first investigated in pure saturated steam conditions in the pressure range from 0.1 to 7 Mpa. The CATHARE film condensation model in pure steam conditions is derived from Chen's correlation. Chen proposes a general correlation for the film condensation, covering the wavy-laminar and the turbulent film regimes and taking into account the interfacial friction effect. A large data base of laminar film regime was used including COTURNE data other available data found in the literature. The analysis of these data base suggests an influence of the liquid Reynolds number, according to the Nusselt theory, and also of the Eoetvoes number, with surface tension effects. A

  11. Measurement techniques of local parameters in the downcomer boiling experiment of APR1400

    International Nuclear Information System (INIS)

    Lee, Eu Hwak

    2004-02-01

    In order to investigate boiling phenomena experimentally in the downcomer during LBLOCA with Direct Vessel Injection (DVI), which is a new Safety Injection System (SIS) of Advanced Power Reactor 1400 MW (APR1400), several parameters should be measured through the verification of their applicability. In this study, measurement techniques of the parameters are developed for the downcomer boiling experiment; local phase velocities, local void fraction and heat flux from the heated wall. The experiment has been performed with the heated wall, which has a thickness of 8.2 cm and a height of 32.5 cm and made of the same material as the prototype (APR1400) with chrome coating against rusting. The newly developed pitot tube is applied to the measurement of local liquid velocity and its calibration curve is obtained experimentally with the consideration of the effect according to water temperature and hole size changes. The developed pitot tube measures the local liquid velocity with 0.69 % deviation and it is confirmed that the water temperature and geometrical change does not affect the calibration curve. The high-speed camera and commercial software are used to measure the local vapor velocity with the accuracy of 0.06 m/sec per pixel and the procedure is confirmed in the present study. It turns out that the vapor velocity is insensitive to void size. High-speed camera and image processing are used to measure the local void fraction with the determined intensity criterion for distinguishing each phase and the results are compared with the bulk void fraction by differential pressure transmitters. In the actual experiment, the developed method is applied successfully and the results show that the criterion of intensity has little effect on local void fraction. And, it is observed that the tendency between the measured local and bulk void faction is maintained with time. In order to measure heat flux from the heated wall, two heat flux measurement techniques are developed

  12. Local mechanical properties of LFT injection molded parts: Numerical simulations versus experiments

    Science.gov (United States)

    Desplentere, F.; Soete, K.; Bonte, H.; Debrabandere, E.

    2014-05-01

    In predictive engineering for polymer processes, the proper prediction of material microstructure from known processing conditions and constituent material properties is a critical step forward properly predicting bulk properties in the finished composite. Operating within the context of long-fiber thermoplastics (LFT, length Autodesk Simulation Moldflow Insight 2014 software has been used. In this software, a fiber breakage algorithm for the polymer flow inside the mold is available. Using well known micro mechanic formulas allow to combine the local fiber length with the local orientation into local mechanical properties. Different experiments were performed using a commercially available glass fiber filled compound to compare the measured data with the numerical simulation results. In this investigation, tensile tests and 3 point bending tests are considered. To characterize the fiber length distribution of the polymer melt entering the mold (necessary for the numerical simulations), air shots were performed. For those air shots, similar homogenization conditions were used as during the injection molding tests. The fiber length distribution is characterized using automated optical method on samples for which the matrix material is burned away. Using the appropriate settings for the different experiments, good predictions of the local mechanical properties are obtained.

  13. Production of clean gasoline from the condensate

    Directory of Open Access Journals (Sweden)

    Noureddin Bentahar

    2013-12-01

    Full Text Available The locally available Algerian bentonite is explored to prepare catalysts for the isomerization of the light fractions of Algerian condensate to produce high quality gasoline of high octane number. Satisfying results are obtained which render these catalysts applicable for a large scale production.

  14. Local content: worldwide trends and the Brazilian experience in the oil and gas sector; Conteudo local: tendencias mundiais e a experiencia brasileira no setor de oleo e gas

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa Junior, Oswaldo A.; Guimaraes, Paulo Buarque [Associacao Brasileira dos Produtores Independentes de Petroleo e Gas - ABPIP, Rio de Janeiro, RJ (Brazil); Fernandez y Fernandez, Eloi [Organizacao Nacional da Industria do Petroleo, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    In recent years a trend on increasing requirements for local investments has been observed worldwide in the petroleum industry. Host countries expect to have increasing social and economical benefits from the development of the oil and gas industry. This expectation drives at a more comprehensive concept of local content to include commitment with social, industrial, and technological development. The Brazilian experience has shown a lot of emphasis on local industry development. Initiatives from governmental authorities and the private sector have been implemented to increase the local industry participation in the oil and gas projects. The current regulation focus on the full and fair opportunities for the local suppliers and the local content commitment established in the E and P concession agreements. A key issue on promoting local content initiatives is to assure that the competitiveness of the indigenous industry will be developed and preserved. The constraints on building up the local industry competitiveness will be addressed, focusing on the taxation overburden, lack of adequate local financing, and internal structural aspects affecting industrial productivity. In addition to this, the experiences on measuring local content for offshore construction and drilling are highlighted. Technology development and technical capability have been addressed by incentive programs for the O and G sector. Finally, the technology learning process and the regulatory requirements to invest in R and D programs conducted by Brazilian technological institutions are discussed. (author)

  15. Alliances for local development success factors. Comparative experiences of Spain and Peru

    Directory of Open Access Journals (Sweden)

    Elsa Del Castillo Mory

    2015-09-01

    Full Text Available Alliances are formed to overcome the constraints partners face to achieve certain goals. When the goal is to promote local development, it requires the participation of stakeholders: private sector, local government, civil associations and community groups, among others. This article seeks, through the comparative analysis of three experiences of local development led by the district of Villa El Salvador (Lima - Peru, the mining company Yanacocha (Cajamarca -Peru and the Spanish Agency for Development Iraugi Lantzen (Basque Country - Spain, to identify the success factors of cooperation agreements for local development. We believe that a better understanding of the factors associated with the success of partnerships could help those who seek the challenge of looking for possible partners, as well as those concerned with the effective management of partnerships in place. The case of Villa El Salvador shows how government support was fundamental in the establishment of the district, but the achievements of this group could not be explained without the active participation of the community. On the other hand, the experience of the company Yanacocha reminds the reader that there is still a big gap to fill in Peru in terms of the joint efforts between private enterprises and stakeholders, and that is necessary to learn from the experiences of those who have gone through part of this path. A different case is shown by the experience of the Spanish Agency Iraugi Lantzen, highlighting the challenges and opportunities that arise from a concerted action between municipal entities pursuing local development. Overall, it can be said that although there are context and situational conditions that favor the development of alliances for development, there are other factors that mediate the success of partnerships. The case studies show that the most successful cooperation experiences are those where there are key individuals that are leaders

  16. Design of a natural draft air-cooled condenser and its heat transfer characteristics in the passive residual heat removal system for 10 MW molten salt reactor experiment

    International Nuclear Information System (INIS)

    Zhao, Hangbin; Yan, Changqi; Sun, Licheng; Zhao, Kaibin; Fa, Dan

    2015-01-01

    As one of the Generation IV reactors, Molten Salt Reactor (MSR) has its superiorities in satisfying the requirements on safety. In order to improve its inherent safety, a concept of passive residual heat removal system (PRHRS) for the 10 MW Molten Salt Reactor Experiment (MSRE) was put forward, which mainly consisted of a fuel drain tank, a feed water tank and a natural draft air-cooled condenser (NDACC). Besides, several valves and pipes are also included in the PRHRS. A NDACC for the PRHRS was preliminarily designed in this paper, which contained a finned tube bundle and a chimney. The tube bundle was installed at the bottom of the chimney for increasing the velocity of the air across the bundle. The heat transfer characteristics of the NDACC were investigated by developing a model of the PRHRS using C++ code. The effects of the environmental temperature, finned tube number and chimney height on heat removal capacity of the NDACC were analyzed. The results show that it has sufficient heat removal capacity to meet the requirements of the residual heat removal for MSRE. The effects of these three factors are obvious. With the decay heat reducing, the heat dissipation power declines after a short-time rise in the beginning. The operation of the NDACC is completely automatic without the need of any external power, resulting in a high safety and reliability of the reactor, especially once the accident of power lost occurs to the power plant. - Highlights: • A model to study the heat transfer characteristics of the NDACC was developed. • The NDACC had sufficient heat removal capacity to remove the decay heat of MSRE. • NDACC heat dissipation power depends on outside temperature and condenser geometry. • As time grown, the effects of outside temperature and condenser geometry diminish. • The NDACC could automatically adjust its heat removal capacity

  17. Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

    International Nuclear Information System (INIS)

    Zhou, W.; Wolf, B.; Revankar, S.T.

    2011-01-01

    The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well. (author)

  18. Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, W., E-mail: wenzzhou@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong (China); Wolf, B. [Purdue University, West Lafayette, IN 47907 (United States); Revankar, S. [Purdue University, West Lafayette, IN 47907 (United States); POSTECH, Pohang (Korea, Republic of)

    2013-11-15

    The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well.

  19. CONDENSATION OF WATER VAPOR IN A VERTICAL TUBE CONDENSER

    Directory of Open Access Journals (Sweden)

    Jan Havlík

    2015-10-01

    Full Text Available This paper presents an analysis of heat transfer in the process of condensation of water vapor in a vertical shell-and-tube condenser. We analyze the use of the Nusselt model for calculating the condensation heat transfer coefficient (HTC inside a vertical tube and the Kern, Bell-Delaware and Stream-flow analysis methods for calculating the shell-side HTC from tubes to cooling water. These methods are experimentally verified for a specific condenser of waste process vapor containing air. The operating conditions of the condenser may be different from the assumptions adopted in the basic Nusselt theory. Modifications to the Nusselt condensation model are theoretically analyzed.

  20. Containment condensing heat transfer

    International Nuclear Information System (INIS)

    Gido, R.G.; Koestel, A.

    1983-01-01

    This report presents a mechanistic heat-transfer model that is valid for large scale containment heat sinks. The model development is based on the determination that the condensation is controlled by mass diffusion through the vapor-air boundary layer, and the application of the classic Reynolds' analogy to formulate expressions for the transfer of heat and mass based on hydrodynamic measurements of the momentum transfer. As a result, the analysis depends on the quantification of the shear stress (momentum transfer) at the interface between the condensate film and the vapor-air boundary layer. In addition, the currently used Tagami and Uchida test observations and their range of applicability are explained

  1. Condensed matter physics

    CERN Document Server

    Isihara, A

    2007-01-01

    More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

  2. Modeling prescribed burning experiments and assessing the fire impacts on local to regional air quality

    Science.gov (United States)

    Zhou, L.; Baker, K. R.; Napelenok, S. L.; Elleman, R. A.; Urbanski, S. P.

    2016-12-01

    Biomass burning, including wildfires and prescribed burns, strongly impact the global carbon cycle and are of increasing concern due to the potential impacts on ambient air quality. This modelling study focuses on the evolution of carbonaceous compounds during a prescribed burning experiment and assesses the impacts of burning on local to regional air quality. The Community Multiscale Air Quality (CMAQ) model is used to conduct 4 and 2 km grid resolution simulations of prescribed burning experiments in southeast Washington state and western Idaho state in summer 2013. The ground and airborne measurements from the field experiment are used to evaluate the model performance in capturing surface and aloft impacts from the burning events. Phase partitioning of organic compounds in the plume are studied as it is a crucial step towards understanding the fate of carbonaceous compounds. The sensitivities of ambient concentrations and deposition to emissions are conducted for organic carbon, elemental carbon and ozone to estimate the impacts of fire on air quality.

  3. Synchronous Condenser Allocation for Improving System Short Circuit Ratio

    DEFF Research Database (Denmark)

    Jia, Jundi; Yang, Guangya; Nielsen, Arne Hejde

    2018-01-01

    With converter-based renewable energy sources increasingly integrated into power systems and conventional power plants gradually phased out, future power systems will experience reduced short circuit strength. The deployment of synchronous condensers can serve as a potential solution. This paper...... presents an optimal synchronous condenser allocation method for improving system short circuit ratio at converter point of common coupling using a modified short circuit analysis approach. The total cost of installing new synchronous condensers is minimized while the system short circuit ratios...

  4. Preoperative and Postoperative Nomograms Incorporating Surgeon Experience for Clinically Localized Prostate Cancer

    Science.gov (United States)

    Kattan, Michael W.; Vickers, Andrew J.; Yu, Changhong; Bianco, Fernando J.; Cronin, Angel M.; Eastham, James A.; Klein, Eric A.; Reuther, Alwyn M.; Pontes, Jose Edson; Scardino, Peter T.

    2012-01-01

    BACKGROUND Accurate preoperative and postoperative risk assessment has been critical for counseling patients regarding radical prostatectomy for clinically localized prostate cancer. In addition to other treatment modalities, neoadjuvant or adjuvant therapies have been considered. The growing literature suggested that the experience of the surgeon may affect the risk of prostate cancer recurrence. The purpose of this study was to develop and internally validate nomograms to predict the probability of recurrence, both preoperatively and postoperatively, with adjustment for standard parameters plus surgeon experience. METHODS The study cohort included 7724 eligible prostate cancer patients treated with radical prostatectomy by 1 of 72 surgeons. For each patient, surgeon experience was coded as the total number of cases conducted by the surgeon before the patient’s operation. Multivariable Cox proportional hazards regression models were developed to predict recurrence. Discrimination and calibration of the models was assessed following bootstrapping methods, and the models were presented as nomograms. RESULTS In this combined series, the 10-year probability of recurrence was 23.9%. The nomograms were quite discriminating (preoperative concordance index, 0.767; postoperative concordance index, 0.812). Calibration appeared to be very good for each. Surgeon experience seemed to have a quite modest effect, especially postoperatively. CONCLUSIONS Nomograms have been developed that consider the surgeon’s experience as a predictor. The tools appeared to predict reasonably well but were somewhat little improved with the addition of surgeon experience as a predictor variable. PMID:19156928

  5. An integrated approach to steam condensation studies inside reactor containments: A review

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Mahesh Kumar [Department of Mechanical Engineering, Indian Institute of Technology Kanpur, 208016 (India); Khandekar, Sameer, E-mail: samkhan@iitk.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Kanpur, 208016 (India); Sharma, Pavan K. [Reactor Safety Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2016-04-15

    Occurrence of severe accidents, such as the Fukushima incident in 2011, is unlikely with a probability of 10{sup −5} per reactor per year. However, such kinds of accidents have serious consequences on both, short term as well as on long term public health, environment and energy policy and security. They also adversely affect the progress of nuclear power industry. Thus, despite such a low probability of occurrence, a need arises to review the safety standards of nuclear power plants, especially in the light of the Fukushima accident. Apart from other systems, a review of thermal-hydraulics and safety system for the reactor containment is vital, as it is the last barrier to radioactive leakage. Main threats to the containment integrity include over-pressurization, not only due to steam alone, but its coupling with the possibility of local hydrogen combustion, depending on the local mixture composition of steam-air-hydrogens. It must be emphasized that steam condensation rate affects the local mixture composition and presence of hydrogen significantly deteriorates the condensation rate. This intrinsic coupling needs to be understood. In this paper, steam condensation and related issues, including basics of condensation, modeling approaches, parameters affecting condensation and experiments performed (in both separate effect and integral test facilities) are critically reviewed, in the light of coupled issues of hydrogen transport and combustion. Such studies are necessary for correlation development and/or to find out the local distribution of steam-hydrogen-air mixture within the containment to locate the possible hydrogen combustion location(s) and hence, deployment of active/passive safety systems. In addition, it is important that future studies, both experimental and numerical modeling, focus on the coupled nature of the problem in a comprehensive manner for ensuring long term safety.

  6. Vortices in trapped Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Jackson, B.

    2000-09-01

    In this thesis we solve the Gross-Pitaevskii equation numerically in order to model the response of trapped Bose-Einstein condensed gases to perturbations by electromagnetic fields. First, we simulate output coupling of pulses from the condensate and compare our results to experiments. The excitation and separation of eigenmodes on flow through a constriction is also studied. We then move on to the main theme of this thesis: the important subject of quantised vortices in Bose condensates, and the relation between Bose-Einstein condensation and superfluidity. We propose methods of producing vortex pairs and rings by controlled motion of objects. Full three-dimensional simulations under realistic experimental conditions are performed in order to test the validity of these ideas. We link vortex formation to drag forces on the object, which in turn is connected with energy transfer to the condensate. We therefore argue that vortex formation by moving objects is intimately related to the onset of dissipation in superfluids. We discuss this idea in the context of a recent experiment, using simulations to provide evidence of vortex formation in the experimental scenario. Superfluidity is also manifest in the property of persistent currents, which is linked to vortex stability and dynamics. We simulate vortex line and ring motion, and find in both cases precessional motion and thermodynamic instability to dissipation. Strictly speaking, the Gross-Pitaevskii equation is valid only for temperatures far below the BEC transition. We end the thesis by describing a simple finite-temperature model to describe mean-field coupling between condensed and non-condensed components of the gas. We show that our hybrid Monte-Carlo/FFT technique can describe damping of the lowest energy excitations of the system. Extensions to this model and future research directions are discussed in the conclusion. (author)

  7. Simple Simulations of DNA Condensation

    Energy Technology Data Exchange (ETDEWEB)

    STEVENS,MARK J.

    2000-07-12

    Molecular dynamics simulations of a simple, bead-spring model of semiflexible polyelectrolytes such as DNA are performed. All charges are explicitly treated. Starting from extended, noncondensed conformations, condensed structures form in the simulations with tetravalent or trivalent counterions. No condensates form or are stable for divalent counterions. The mechanism by which condensates form is described. Briefly, condensation occurs because electrostatic interactions dominate entropy, and the favored Coulombic structure is a charge ordered state. Condensation is a generic phenomena and occurs for a variety of polyelectrolyte parameters. Toroids and rods are the condensate structures. Toroids form preferentially when the molecular stiffness is sufficiently strong.

  8. Vapor condensation device

    International Nuclear Information System (INIS)

    Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

    1992-01-01

    The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

  9. Condensed matter physics

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The condensed matter physics research in the Physics Department of Risoe National Laboratory is predominantly experimental utilising diffraction of neutrons and x-rays. The research topics range from studies of structure, excitations and phase transitions in model systems to studies of ion transport, texture and recrystallization kinetics with a more applied nature. (author)

  10. Bose-Einstein Condensation

    Indian Academy of Sciences (India)

    absolute zero. These ideas had ... Everybody is talking about Bose-Einstein condensation. This discovery ... needed if we want to find the probability distribution of the x- ... Boltzmann took two approaches to the problem, both of them deep and ...

  11. Condensed matter physics

    International Nuclear Information System (INIS)

    1990-01-01

    This is a summary of condensed matter physics in Brazil. It discusses as well, the perspectives and financing evolved in this research area for the next decade. It is specially concerned with semiconductors, magnetic materials, superconductivity, polymers, glasses, crystals ceramics, statistical physics, magnetic resonance and Moessbauer spectroscopy. (A.C.A.S.)

  12. Preventing freezing of condensate inside tubes of air cooled condenser

    International Nuclear Information System (INIS)

    Joo, Jeong A; Hwang, In Hwan; Lee, Dong Hwan; Cho, Young Il

    2012-01-01

    An air cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred

  13. Fermion masses through four-fermion condensates

    Energy Technology Data Exchange (ETDEWEB)

    Ayyar, Venkitesh [Department of Physics, Duke University,Science Drive, Durham, NC 27708 (United States); Chandrasekharan, Shailesh [Department of Physics, Duke University,Science Drive, Durham, NC 27708 (United States); Center for High Energy Physics, Indian Institute of Science,C.V. Raman Avenue, Bangalore, 560012 (India)

    2016-10-12

    Fermion masses can be generated through four-fermion condensates when symmetries prevent fermion bilinear condensates from forming. This less explored mechanism of fermion mass generation is responsible for making four reduced staggered lattice fermions massive at strong couplings in a lattice model with a local four-fermion coupling. The model has a massless fermion phase at weak couplings and a massive fermion phase at strong couplings. In particular there is no spontaneous symmetry breaking of any lattice symmetries in both these phases. Recently it was discovered that in three space-time dimensions there is a direct second order phase transition between the two phases. Here we study the same model in four space-time dimensions and find results consistent with the existence of a narrow intermediate phase with fermion bilinear condensates, that separates the two asymptotic phases by continuous phase transitions.

  14. CAPILLARY CONDENSATION IN MMS AND PORE STRUCTURE CHARACTERIZATION. (R825959)

    Science.gov (United States)

    Phenomena of capillary condensation and desorption in siliceous mesoporous molecular sieves (MMS) with cylindrical channels are studied by means of the non-local density functional theory (NLDFT). The results are compared with macroscopic thermodynamic approaches based on Kelv...

  15. Elastic extension of a local analysis facility on external clouds for the LHC experiments

    Science.gov (United States)

    Ciaschini, V.; Codispoti, G.; Rinaldi, L.; Aiftimiei, D. C.; Bonacorsi, D.; Calligola, P.; Dal Pra, S.; De Girolamo, D.; Di Maria, R.; Grandi, C.; Michelotto, D.; Panella, M.; Taneja, S.; Semeria, F.

    2017-10-01

    The computing infrastructures serving the LHC experiments have been designed to cope at most with the average amount of data recorded. The usage peaks, as already observed in Run-I, may however originate large backlogs, thus delaying the completion of the data reconstruction and ultimately the data availability for physics analysis. In order to cope with the production peaks, the LHC experiments are exploring the opportunity to access Cloud resources provided by external partners or commercial providers. In this work we present the proof of concept of the elastic extension of a local analysis facility, specifically the Bologna Tier-3 Grid site, for the LHC experiments hosted at the site, on an external OpenStack infrastructure. We focus on the Cloud Bursting of the Grid site using DynFarm, a newly designed tool that allows the dynamic registration of new worker nodes to LSF. In this approach, the dynamically added worker nodes instantiated on an OpenStack infrastructure are transparently accessed by the LHC Grid tools and at the same time they serve as an extension of the farm for the local usage.

  16. Experience of BESIII data production with local cluster and distributed computing model

    International Nuclear Information System (INIS)

    Deng, Z Y; Li, W D; Liu, H M; Sun, Y Z; Zhang, X M; Lin, L; Nicholson, C; Zhemchugov, A

    2012-01-01

    The BES III detector is a new spectrometer which works on the upgraded high-luminosity collider, BEPCII. The BES III experiment studies physics in the tau-charm energy region from 2 GeV to 4.6 GeV . From 2009 to 2011, BEPCII has produced 106M ψ(2S) events, 225M J/ψ events, 2.8 fb −1 ψ(3770) data, and 500 pb −1 data at 4.01 GeV. All the data samples were processed successfully and many important physics results have been achieved based on these samples. Doing data production correctly and efficiently with limited CPU and storage resources is a big challenge. This paper will describe the implementation of the experiment-specific data production for BESIII in detail, including data calibration with event-level parallel computing model, data reconstruction, inclusive Monte Carlo generation, random trigger background mixing and multi-stream data skimming. Now, with the data sample increasing rapidly, there is a growing demand to move from solely using a local cluster to a more distributed computing model. A distributed computing environment is being set up and expected to go into production use in 2012. The experience of BESIII data production, both with a local cluster and with a distributed computing model, is presented here.

  17. Coupled Josephson local oscillator and detector experiments in the terahertz regime

    International Nuclear Information System (INIS)

    Robertazzi, R.P.; Hallen, H.D.; Buhrman, R.A.

    1988-01-01

    Recent coupled Josephson junction experiments in the authors' laboratory have demonstrated that high critical current density tunnel junctions can serve as effective local oscillators at frequencies up to and in excess of the gap sum frequency of the junction, i.e. well above 1 Terahertz for a niobium or niobium compound tunnel junction. While the details of the behavior of such a THz. oscillator were found not to be in accord with the predictions of the accepted theory of the A.C. Josephson effect in the gap region significant radiation could be capacitively coupled from the oscillator junction to an adjacent junction, sufficient for SIS mixer experiments at Terahertz frequencies. Research efforts are now under way to further extend and expand these studies. A high critical current density all NbN tunnel junction system is now under development for Terahertz applications and a new set of coupled Josephson oscillator - SIS detector experiments is being initiated using NbN tunnel junctions. In this paper the authors review the original coupled junction high frequency experiments and report on the recent progress of the current NbN tunnel junction experiments

  18. Dropwise condensation on hydrophobic bumps and dimples

    Science.gov (United States)

    Yao, Yuehan; Aizenberg, Joanna; Park, Kyoo-Chul

    2018-04-01

    Surface topography plays an important role in promoting or suppressing localized condensation. In this work, we study the growth of water droplets on hydrophobic convex surface textures such as bumps and concave surface textures such as dimples with a millimeter scale radius of curvature. We analyze the spatio-temporal droplet size distribution under a supersaturation condition created by keeping the uniform surface temperature below the dew point and show its relationship with the sign and magnitude of the surface curvature. In particular, in contrast to the well-known capillary condensation effect, we report an unexpectedly less favorable condensation on smaller, millimeter-scale dimples where the capillary condensation effect is negligible. To explain these experimental results, we numerically calculated the diffusion flux of water vapor around the surface textures, showing that its magnitude is higher on bumps and lower on dimples compared to a flat surface. We envision that our understanding of millimetric surface topography can be applied to improve the energy efficiency of condensation in applications such as water harvesting, heating, ventilation, and air conditioning systems for buildings and transportation, heat exchangers, thermal desalination plants, and fuel processing systems.

  19. Localized reactive flow in carbonate rocks: Core-flood experiments and network simulations

    Science.gov (United States)

    Wang, Haoyue; Bernabé, Yves; Mok, Ulrich; Evans, Brian

    2016-11-01

    We conducted four core-flood experiments on samples of a micritic, reef limestone from Abu Dhabi under conditions of constant flow rate. The pore fluid was water in equilibrium with CO2, which, because of its lowered pH, is chemically reactive with the limestone. Flow rates were between 0.03 and 0.1 mL/min. The difference between up and downstream pore pressures dropped to final values ≪1 MPa over periods of 3-18 h. Scanning electron microscope and microtomography imaging of the starting material showed that the limestone is mostly calcite and lacks connected macroporosity and that the prevailing pores are few microns large. During each experiment, a wormhole formed by localized dissolution, an observation consistent with the decreases in pressure head between the up and downstream reservoirs. Moreover, we numerically modeled the changes in permeability during the experiments. We devised a network approach that separated the pore space into competing subnetworks of pipes. Thus, the problem was framed as a competition of flow of the reactive fluid among the adversary subnetworks. The precondition for localization within certain time is that the leading subnetwork rapidly becomes more transmissible than its competitors. This novel model successfully simulated features of the shape of the wormhole as it grew from few to about 100 µm, matched the pressure history patterns, and yielded the correct order of magnitude of the breakthrough time. Finally, we systematically studied the impact of changing the statistical parameters of the subnetworks. Larger mean radius and spatial correlation of the leading subnetwork led to faster localization.

  20. En bloc urinary bladder resection for locally advanced colorectal cancer: a 17-year experience.

    Science.gov (United States)

    Li, Jimmy C M; Chong, Charing C N; Ng, Simon S M; Yiu, Raymond Y C; Lee, Janet F Y; Leung, Ka Lau

    2011-09-01

    En bloc bladder resection is often required for treating colorectal cancer with suspected urinary bladder invasion. Our aim was to review our institutional experience in en bloc resection of locally advanced colorectal cancer involving the urinary bladder over a period of 17 years. The hospital records of 72 patients with locally advanced colorectal cancer who underwent en bloc urinary bladder resection at our institution between July 1987 and December 2004 were retrospectively reviewed. Clinical and oncologic outcomes were evaluated. The mean duration of follow-up was 64.3 months. Genuine tumor invasion into the urinary bladder was confirmed in 34 patients (47%) by histopathology. Forty patients (56%) underwent primary closure of the urinary bladder, while 32 patients (44%) required various kinds of urologic reconstructive procedures. Operative mortality occurred in four patients (6%). The overall postoperative morbidity rate was significantly higher in patients undergoing urologic reconstruction (81% vs. 45%, p = 0.002) when compared to that in patients undergoing primary closure. This was mostly attributable to significantly higher rates of urinary anastomotic leak (21.9% vs. 0%, p = 0.002) and urinary tract infection (50% vs. 18%, p = 0.003) in the urologic reconstruction group. For the 57 patients (79%) who underwent curative resection, the 5-year overall survival rate was 59%, and the local recurrence at 5 years was 15%. Both parameters were not significantly affected by the presence of pathologic bladder invasion or the extent of surgical procedures. En bloc bladder resection for locally advanced colorectal cancer involving the urinary bladder can produce reasonable long-term local control and patient survival.

  1. Locally advanced cervix cancer: chemotherapy prior to definitive surgery or radiotherapy. A single institutional experience

    International Nuclear Information System (INIS)

    MacLeod, C.; O'Donnell, A.; Tattersall, M.H.N.; Dalrymple, C.; Firth, I.

    2001-01-01

    Primary or neoadjuvant chemotherapy prior to definitive local therapy has potential advantages for locally advanced cervix cancer. It can down stage a cancer and allow definitive local therapy to be technically possible (surgery), or potentially more effective (radiotherapy). It can also eradicate subclinical systemic metastases. This report reviews a single institution's experience of neoadjuvant chemotherapy prior to definitive local therapy for cervix cancer over a 13-year period. One hundred and six patients were treated with this intent. The patients were analysed for their response to chemotherapy, treatment received, survival, relapse and toxicity. The chemotherapy was feasible and the majority of patients had a complete or partial response (58.5%). Eight patients did not proceed to local treatment. Forty-six patients had definitive surgery and 52 had definitive radiotherapy. The 5-year overall survival was 27% and the majority of patients died with disease. The first site of relapse was usually in the pelvis (46.2%). Late complications that required ongoing medical therapy (n = 6) or surgical intervention (n = 2) were recorded in eight patients (7.5%). On univariate analysis stage (P= 0.04), tumour size (P = 0.01), lymph node status (P=0.003), response to chemotherapy (P = 0.045) and treatment (P = 0.003) were all significant predictors of survival. On multivariate analysis, tumour size (P < 0.0001) and nodal status (P = 0.02) were significant predictors of survival. Despite the impressive responses to chemotherapy of advanced cervix cancer, there is evidence from randomized trials that it does not improve or compromise survival prior to radiotherapy. As its role prior to surgery remains unclear, it should not be used in this setting outside a prospective randomized trial. Copyright (2001) Blackwell Science Pty Ltd

  2. Evaporation and condensation at a liquid surface. II. Methanol

    Science.gov (United States)

    Matsumoto, Mitsuhiro; Yasuoka, Kenji; Kataoka, Yosuke

    1994-11-01

    The rates of evaporation and condensation of methanol under the vapor-liquid equilibrium condition at the temperature of 300 and 350 K are investigated with a molecular dynamics computer simulation. Compared with the argon system (reported in part I), the ratio of self-reflection is similar (˜10%), but the ratio of molecule exchange is several times larger than the argon, which suggests that the conventional assumption of condensation as a unimolecular process completely fails for associating fluids. The resulting total condensation coefficient is 20%-25%, and has a quantitative agreement with a recent experiment. The temperature dependence of the evaporation-condensation behavior is not significant.

  3. 1D models for condensation induced water hammer in pipelines

    International Nuclear Information System (INIS)

    Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas

    2013-01-01

    Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

  4. 1D models for condensation induced water hammer in pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas [TUEV NORD SysTec GmbH und Co. KG, Hamburg (Germany)

    2013-03-15

    Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

  5. Bose Condensate in He II

    International Nuclear Information System (INIS)

    Svensson, E.C.

    1984-01-01

    The Condensate Saga, now halfway through its fifth decade, is reviewed. The recent neutron-scattering work which has at last convincingly established that there is indeed a Bose Condensate in He II is described

  6. Maintaining steam/condensate lines

    International Nuclear Information System (INIS)

    Russum, S.A.

    1992-01-01

    Steam and condensate systems must be maintained with the same diligence as the boiler itself. Unfortunately, they often are not. The water treatment program, critical to keeping the boiler at peak efficiency and optimizing operating life, should not stop with the boiler. The program must encompass the steam and condensate system as well. A properly maintained condensate system maximizes condensate recovery, which is a cost-free energy source. The fuel needed to turn the boiler feedwater into steam has already been provided. Returning the condensate allows a significant portion of that fuel cost to be recouped. Condensate has a high heat content. Condensate is a readily available, economical feedwater source. Properly treated, it is very pure. Condensate improves feedwater quality and reduces makeup water demand and pretreatment costs. Higher quality feedwater means more reliable boiler operation

  7. Continuous condensation in nanogrooves

    Science.gov (United States)

    Malijevský, Alexandr

    2018-05-01

    We consider condensation in a capillary groove of width L and depth D , formed by walls that are completely wet (contact angle θ =0 ), which is in a contact with a gas reservoir of the chemical potential μ . On a mesoscopic level, the condensation process can be described in terms of the midpoint height ℓ of a meniscus formed at the liquid-gas interface. For macroscopically deep grooves (D →∞ ), and in the presence of long-range (dispersion) forces, the condensation corresponds to a second-order phase transition, such that ℓ ˜(μcc-μ ) -1 /4 as μ →μcc - where μc c is the chemical potential pertinent to capillary condensation in a slit pore of width L . For finite values of D , the transition becomes rounded and the groove becomes filled with liquid at a chemical potential higher than μc c with a difference of the order of D-3. For sufficiently deep grooves, the meniscus growth initially follows the power law ℓ ˜(μcc-μ ) -1 /4 , but this behavior eventually crosses over to ℓ ˜D -(μ-μc c) -1 /3 above μc c, with a gap between the two regimes shown to be δ ¯μ ˜D-3 . Right at μ =μc c , when the groove is only partially filled with liquid, the height of the meniscus scales as ℓ*˜(D3L) 1 /4 . Moreover, the chemical potential (or pressure) at which the groove is half-filled with liquid exhibits a nonmonotonic dependence on D with a maximum at D ≈3 L /2 and coincides with μc c when L ≈D . Finally, we show that condensation in finite grooves can be mapped on the condensation in capillary slits formed by two asymmetric (competing) walls a distance D apart with potential strengths depending on L . All these predictions, based on mesoscopic arguments, are confirmed by fully microscopic Rosenfeld's density functional theory with a reasonable agreement down to surprisingly small values of both L and D .

  8. Re-distribution (condensation) of magnons in a ferromagnet under pumping

    International Nuclear Information System (INIS)

    Zvyagin, A.A.

    2008-01-01

    In recent years several experiments have been performed to study the Bose-Einstein condensation of quasiparticles, in particular, magnons in magnetically ordered systems. Recently the Bose-Einstein condensation of magnons was observed at room temperatures in a ferromagnetic film. A theory of the condensation (redistribution) of magnons under the conditions of pumping, which explains many features of that experiment, is presented. The use of the term 'Bose-Einstein condensation of magnons' is discussed

  9. TFE-induced local unfolding and fibrillation of SOD1: bridging the experiment and simulation studies.

    Science.gov (United States)

    Kumar, Vijay; Prakash, Amresh; Pandey, Preeti; Lynn, Andrew M; Hassan, Md Imtaiyaz

    2018-05-18

    Misfolding and aggregation of Cu, Zn Superoxide dismutase (SOD1) is involved in the neurodegenerative disease, amyotrophic lateral sclerosis. Many studies have shown that metal-depleted, monomeric form of SOD1 displays substantial local unfolding dynamics and is the precursor for aggregation. Here, we have studied the structure and dynamics of different apo monomeric SOD1 variants associated with unfolding and aggregation in aqueous trifluoroethanol (TFE) through experiments and simulation. TFE induces partially unfolded β-sheet-rich extended conformations in these SOD1 variants, which subsequently develops aggregates with fibril-like characteristics. Fibrillation was achieved more easily in disulfide-reduced monomeric SOD1 when compared with wild-type and mutant monomeric SOD1. At higher concentrations of TFE, a native-like structure with the increase in α-helical content was observed. The molecular dynamics simulation results illustrate distinct structural dynamics for different regions of SOD1 variants and show uniform local unfolding of β-strands. The strands protected by the zinc-binding and electrostatic loops were found to unfold first in 20% (v/v) TFE, leading to a partial unfolding of β-strands 4, 5, and 6 which are prone to aggregation. Our results thus shed light on the role of local unfolding and conformational dynamics in SOD1 misfolding and aggregation. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  10. Local Helicity Injection Systems for Non-solenoidal Startup in the PEGASUS Toroidal Experiment

    Science.gov (United States)

    Perry, J. M.; Barr, J. L.; Bongard, M. W.; Fonck, R. J.; Hinson, E. T.; Lewicki, B. T.; Redd, A. J.

    2013-10-01

    Local helicity injection is being developed in the PEGASUS Toroidal Experiment for non-solenoidal startup in spherical tokamaks. The effective loop voltage due to helicity injection scales with the area of the injectors, requiring the development of electron current injectors with areas much larger than the 2 cm2 plasma arc injectors used to date. Solid and gas-effused metallic electrodes were found to be unusable due to reduced injector area utilization from localized cathode spots and narrow operational regimes. An integrated array of 8 compact plasma arc sources is thus being developed for high current startup. It employs two monolithic power systems, for the plasma arc sources and the bias current extraction system. The array effectively eliminates impurity fueling from plasma-material interaction by incorporating a local scraper-limiter and conical-frustum bias electrodes to mitigate the effects of cathode spots. An energy balance model of helicity injection indicates that the resulting 20 cm2 of total injection area should provide sufficient current drive to reach 0.3 MA. At that level, helicity injection drive exceeds that from poloidal induction, which is the relevant operational regime for large-scale spherical tokamaks. Future placement of the injector array near an expanded boundary divertor region will test simultaneous optimization of helicity drive and the Taylor relaxation current limit. Work supported by US DOE Grant DE-FG02-96ER54375.

  11. Strain Localization and Weakening Processes in Viscously Deforming Rocks: Numerical Modeling Based on Laboratory Torsion Experiments

    Science.gov (United States)

    Doehmann, M.; Brune, S.; Nardini, L.; Rybacki, E.; Dresen, G.

    2017-12-01

    Strain localization is an ubiquitous process in earth materials observed over a broad range of scales in space and time. Localized deformation and the formation of shear zones and faults typically involves material softening by various processes, like shear heating and grain size reduction. Numerical modeling enables us to study the complex physical and chemical weakening processes by separating the effect of individual parameters and boundary conditions. Using simple piece-wise linear functions for the parametrization of weakening processes allows studying a system at a chosen (lower) level of complexity (e.g. Cyprych et al., 2016). In this study, we utilize a finite element model to test two weakening laws that reduce the strength of the material depending on either the I) amount of accumulated strain or II) deformational work. Our 2D Cartesian models are benchmarked to single inclusion torsion experiments performed at elevated temperatures of 900 °C and pressures of up to 400 MPa (Rybacki et al., 2014). The experiments were performed on Carrara marble samples containing a weak Solnhofen limestone inclusion at a maximum strain rate of 2.0*10-4 s-1. Our models are designed to reproduce shear deformation of a hollow cylinder equivalent to the laboratory setup, such that material leaving one side of the model in shear direction enters again on the opposite side using periodic boundary conditions. Similar to the laboratory tests, we applied constant strain rate and constant stress boundary conditions.We use our model to investigate the time-dependent distribution of stress and strain and the effect of different parameters. For instance, inclusion rotation is shown to be strongly dependent on the viscosity ratio between matrix and inclusion and stronger ductile weakening increases the localization rate while decreasing shear zone width. The most suitable weakening law for representation of ductile rock is determined by combining the results of parameter tests with

  12. Keeping condensers clean

    Energy Technology Data Exchange (ETDEWEB)

    Wicker, K.

    2006-04-15

    The humble condenser is among the biggest contributors to a steam power plant's efficiency. But although a clean condenser can provide great economic benefit, a dirty one can raise plant heat rate, resulting in large losses of generation revenue and/or unnecessarily high fuel bills. Conventional methods for cleaning fouled tubes range form chemicals to scrapers to brushes and hydro-blasters. This article compares the available options and describes how one power station, Omaha Public Power District's 600 MW North Omaha coal-fired power station, cleaned up its act. The makeup and cooling water of all its five units comes from the Missouri River. 6 figs.

  13. Condensed matter physics

    CERN Document Server

    Marder, Michael P

    2010-01-01

    This Second Edition presents an updated review of the whole field of condensed matter physics. It consolidates new and classic topics from disparate sources, teaching not only about the effective masses of electrons in semiconductor crystals and band theory, but also about quasicrystals, dynamics of phase separation, why rubber is more floppy than steel, granular materials, quantum dots, Berry phases, the quantum Hall effect, and Luttinger liquids.

  14. Working with local nurses to promote hospital-nursing care during humanitarian assignments overseas: experiences from the perspectives of nurses.

    Science.gov (United States)

    Tjoflåt, Ingrid; Karlsen, Bjørg; Saetre Hansen, Britt

    2016-06-01

    To describe how Norwegian expatriate nurses engaged in humanitarian assignments overseas experience working with the local nurses promoting nursing care in the hospital ward. Western countries have a long tradition of providing nurses with expert knowledge in nursing care for humanitarian projects and international work overseas. Studies from humanitarian mission revealed that health workers rarely acknowledge or use the local knowledge. However, there is a lack of studies highlighting expatriate nurses' experiences working with local nurses to promote nursing care in the hospital ward. This study applies a descriptive explorative qualitative design. The data were collected in 2013 by means of seven semi-structured interviews and analysed using qualitative content analysis. The data analyses revealed three themes related to the expatriate nurses' experiences of working with the local nurses to promote nursing care in the hospital ward: (1) Breaking the code, (2) Colliding worlds and (3) Challenges in sharing knowledge. The findings reflect different challenges when working with the local nurses. Findings indicate valuable knowledge gained about local nursing care and the local health and educational system. They also demonstrate challenges for the expatriate nurses related to the local nursing standard in the wards and using the local nurses' experiences and knowledge when working together. The findings can inform nurses, humanitarian organisations and institutions working overseas regarding the recruitment and the preparation of nurses who want to work cross- culturally or in humanitarian missions overseas. © 2016 John Wiley & Sons Ltd.

  15. Bose-Einstein condensation of atomic gases

    International Nuclear Information System (INIS)

    Anglin, J. R.; Ketterle, W.

    2003-01-01

    The early experiments on Bose-Einstein condensation in dilute atomic gases accomplished three longstanding goals. First, cooling of neutral atoms into their motional state, thus subjecting them to ultimate control, limited only by Heisenberg uncertainty relation. Second, creation of a coherent sample of atoms, in which all occupy the same quantum states, and the realization of atom lasers - devices that output coherent matter waves. And third, creation of gaseous quantum fluid, with properties that are different from the quantum liquids helium-3 and helium-4. The field of Bose-Einstein condensation of atomic gases has continued to progress rapidly, driven by the combination of new experimental techniques and theoretical advances. The family of quantum degenerate gases has grown, and now includes metastable and fermionic atoms. condensates have become an ultralow-temperature laboratory for atom optics, collisional physics and many-body physics, encompassing phonons, superfluidity, quantized vortices, Josephson junctions and quantum phase transitions. (author)

  16. Using helical compressors for coke gas condensation

    Energy Technology Data Exchange (ETDEWEB)

    Privalov, V E; Rezunenko, Yu I; Lelyanov, N V; Zarnitzkii, G Eh; Gordienko, A A; Derebenko, I F; Venzhega, A G; Leonov, N P; Gorokhov, N N

    1982-08-01

    Coke oven gas compression is discussed. Presently used multilevel piston compressors are criticized. The paper recommends using helical machines which combine advantages of using volume condensing compressors and compact high-efficiency centrifugal machines. Two kinds of helical compressors are evaluated: dry and oil-filled; their productivities and coke oven gas chemical composition are analyzed. Experiments using helical compressors were undertaken at the Yasinovskii plant. Flowsheet of the installation is shown. Performance results are given in a table. For all operating conditions content of insolubles in oil compounds is found to be lower than the acceptable value (0.08%). Compressor productivity measurements with variable manifold pressure are evaluated. Figures obtained show that efficient condensation of raw coke oven gas is possible. Increasing oil-filled compressor productivity is recommended by decreasing amount of oil injected and simultaneously increasing rotation speed. The dry helical compressor with water seal is found to be most promising for raw coke oven gas condensation. (10 refs.)

  17. BWR condensate filtration studies

    International Nuclear Information System (INIS)

    Wilson, J.A.; Pasricha, A.; Rekart, T.E.

    1993-09-01

    Poor removal of particulate corrosion products (especially iron) from condensate is one of the major problems in BWR systems. The presence of activated corrosion products creates ''hot spots'' and increases piping dose rates. Also, fuel efficiency is reduced and the risk of fuel failure is increased by the deposit of corrosion products on the fuel. Because of these concerns, current EPRI guidelines call for a maximum of 2 ppb of iron in the reactor feedwater with a level of 0.5 ppb being especially desirable. It has become clear that conventional deep bed resins are incapable of meeting these levels. While installation of prefilter systems is an option, it would be more economical for plants with naked deep beds to find an improved bead resin for use in existing systems. BWR condensate filtration technologies are being tested on a condensate side stream at Hope Creek Nuclear Generating Station. After two years of testing, hollow fiber filters (HFF) and fiber matrix filters (FMF), and low crosslink cation resin, all provide acceptable results. The results are presented for pressure drop, filtration efficiency, and water quality measurements. The costs are compared for backwashable non-precoat HFF and FMF. Results are also presented for full deep bed vessel tests of the low crosslink cation resin

  18. Polymorphism of Lysozyme Condensates.

    Science.gov (United States)

    Safari, Mohammad S; Byington, Michael C; Conrad, Jacinta C; Vekilov, Peter G

    2017-10-05

    Protein condensates play essential roles in physiological processes and pathological conditions. Recently discovered mesoscopic protein-rich clusters may act as crucial precursors for the nucleation of ordered protein solids, such as crystals, sickle hemoglobin polymers, and amyloid fibrils. These clusters challenge settled paradigms of protein condensation as the constituent protein molecules present features characteristic of both partially misfolded and native proteins. Here we employ the antimicrobial enzyme lysozyme and examine the similarities between mesoscopic clusters, amyloid structures, and disordered aggregates consisting of chemically modified protein. We show that the mesoscopic clusters are distinct from the other two classes of aggregates. Whereas cluster formation and amyloid oligomerization are both reversible, aggregation triggered by reduction of the intramolecular S-S bonds is permanent. In contrast to the amyloid structures, protein molecules in the clusters retain their enzymatic activity. Furthermore, an essential feature of the mesoscopic clusters is their constant radius of less than 50 nm. The amyloid and disordered aggregates are significantly larger and rapidly grow. These findings demonstrate that the clusters are a product of limited protein structural flexibility. In view of the role of the clusters in the nucleation of ordered protein solids, our results suggest that fine-tuning the degree of protein conformational stability is a powerful tool to control and direct the pathways of protein condensation.

  19. Asymmetric condensed dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, Anthony; Diez-Tejedor, Alberto, E-mail: aguirre@scipp.ucsc.edu, E-mail: alberto.diez@fisica.ugto.mx [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA, 95064 (United States)

    2016-04-01

    We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component would develop a Bose-Einstein condensate in the early universe that, for appropriate model parameters, could survive the ensuing cosmological evolution until now. The condensation of a dark matter component in equilibrium with the thermal plasma is a relativistic process, hence the amount of matter dictated by the charge asymmetry is complemented by a hot relic density frozen out at the time of decoupling. Contrary to the case of ordinary WIMPs, dark matter particles in a condensate must be lighter than a few tens of eV so that the density from thermal relics is not too large. Big-Bang nucleosynthesis constrains the temperature of decoupling to the scale of the QCD phase transition or above. This requires large dark matter-to-photon ratios and very weak interactions with standard model particles.

  20. Stochastic Models for the Kinematics of Moisture Transport and Condensation in Homogeneous Turbulent Flows

    OpenAIRE

    O'Gorman, Paul A.; Schneider, Tapio

    2006-01-01

    The transport of a condensing passive scalar is studied as a prototype model for the kinematics of moisture transport on isentropic surfaces. Condensation occurs whenever the scalar concentration exceeds a specified local saturation value. Since condensation rates are strongly nonlinear functions of moisture content, the mean moisture flux is generally not diffusive. To relate the mean moisture content, mean condensation rate, and mean moisture flux to statistics of the advecting velocity fie...

  1. Condenser performance monitoring and cleaning

    International Nuclear Information System (INIS)

    Walden, J.V.

    1998-01-01

    The main condenser at Ginna Station was retubed from admiralty brass to 316 stainless steel. A condenser performance monitoring spreadsheet was developed using EPRI guidelines after fouling was discovered. PEPSE computer models were used to determine the power loss and confirm the spreadsheet results. Cleaning of the condenser was performed using plastic scrubbers. Condenser performance improved dramatically following the cleaning. PEPSE, condenser spreadsheet performance, and actual observed plant data correlated well together. The fouling mechanism was determined to be a common lake bacteria and fungus growth which was combined with silt. Chlorination of the circulating water system at the allowable limits is keeping the biofouling under control

  2. Experimental Investigation of Flow Condensation in Microgravity

    Science.gov (United States)

    Lee, Hyoungsoon; Park, Ilchung; Konishi, Christopher; Mudawar, Issam; May, Rochelle I.; Juergens, Jeffery R.; Wagner, James D.; Hall, Nancy R.; Nahra, Henry K.; Hasan, Mohammed M.; hide

    2013-01-01

    Future manned missions to Mars are expected to greatly increase the space vehicle's size, weight, and heat dissipation requirements. An effective means to reducing both size and weight is to replace single-phase thermal management systems with two-phase counterparts that capitalize upon both latent and sensible heat of the coolant rather than sensible heat alone. This shift is expected to yield orders of magnitude enhancements in flow boiling and condensation heat transfer coefficients. A major challenge to this shift is a lack of reliable tools for accurate prediction of two-phase pressure drop and heat transfer coefficient in reduced gravity. Developing such tools will require a sophisticated experimental facility to enable investigators to perform both flow boiling and condensation experiments in microgravity in pursuit of reliable databases. This study will discuss the development of the Flow Boiling and Condensation Experiment (FBCE) for the International Space Station (ISS), which was initiated in 2012 in collaboration between Purdue University and NASA Glenn Research Center. This facility was recently tested in parabolic flight to acquire condensation data for FC-72 in microgravity, aided by high-speed video analysis of interfacial structure of the condensation film. The condensation is achieved by rejecting heat to a counter flow of water, and experiments were performed at different mass velocities of FC-72 and water and different FC-72 inlet qualities. It is shown that the film flow varies from smooth-laminar to wavy-laminar and ultimately turbulent with increasing FC-72 mass velocity. The heat transfer coefficient is highest near the inlet of the condensation tube, where the film is thinnest, and decreases monotonically along the tube, except for high FC-72 mass velocities, where the heat transfer coefficient is enhanced downstream. This enhancement is attributed to both turbulence and increased interfacial waviness. One-ge correlations are shown to

  3. Analytical study of condensation heat transfer on titanium tube with super-hydrophobic surface

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Dae Yun; Park, Hyun Gyu; Lee, Kwon Yeong [Handong Global University, Pohang (Korea, Republic of)

    2016-05-15

    There are many nuclear or fossil power plants which occupy more than 85% among entire power plants in the world. These plants release heat through condenser into nature. The condenser is an important component for cooling the working fluid after the turbine. Its performance is related with material and size of its tubes. To have good performance or to reduce condenser size, it is important to increase condensation heat transfer coefficient on condenser tubes. Ma et al. executed heat transfer experiment in dropwise condensation with non-condensable gas, and studied how the amount of air and pressure difference affect condensation heat transfer coefficient. The more non-condensable gas existed, the condensation heat transfer coefficient was decreased. Shen et al. studied condensation heat transfer at horizontal bundle tubes. Several variables such as coolant velocity, saturated pressure, and surface conditions were studied. As a result, surface modified brass tube and stainless tube showed higher condensation heat transfer coefficient as much as 1.3 and 1.4 times comparing with their bare tubes, in 70 kPa vacuum condition respectively. Rausch et al. studied dropwise condensation on ion-implanted titanium surface. Experimental study is performed to evaluate the performance of surface modified titanium tube in vacuum state. SAM coating is used to make super-hydrophobic surface of titanium tube. Preliminary analysis were performed considering filmwise and dropwise condensations, respectively. Experiment facility is almost prepared and the test result will be shown soon.

  4. Thermal hydraulic behavior of sub-assembly local blockage in China experiment fast reactor

    International Nuclear Information System (INIS)

    Yang Zhimin

    2000-01-01

    The geometrical parameter ratio of pitch to diameter of China Experiment Fast Reactor (CEFR) subassembly is 1,167. To address the thermal hydraulic behavior of subassembly local blockage which may be caused by deformation of cladding due to severe swelling and thermal stresses and by space swirl loosening etc., the porous numerical model and SIMPLE-P code used to solve Navier-Stokes and energy equations in porous medium was developed, and the bundle experiment with 19 pins with 24 subchannels blocked in the sodium coolant was carried on in China Institute of Atomic Energy (CIAE). The comparison of code predictions against experiments (including non-blockage and ten blockage conditions) seems well. The thermal hydraulic behavior of fuel subassembly with 61 fuel pins blockage of CEFR is calculated with SIMPLE-P code. The results indicate that the maximum temperature is 815 deg. C when the blockage area is about 37% (54 central subchannels are blocked). In this case the cladding won't be damaged and no sodium coolant boiling takes place. (author)

  5. Local Navon letter processing affects skilled behavior: a golf-putting experiment.

    Science.gov (United States)

    Lewis, Michael B; Dawkins, Gemma

    2015-04-01

    Expert or skilled behaviors (for example, face recognition or sporting performance) are typically performed automatically and with little conscious awareness. Previous studies, in various domains of performance, have shown that activities immediately prior to a task demanding a learned skill can affect performance. In sport, describing the to-be-performed action is detrimental, whereas in face recognition, describing a face or reading local Navon letters is detrimental. Two golf-putting experiments are presented that compare the effects that these three tasks have on experienced and novice golfers. Experiment 1 found a Navon effect on golf performance for experienced players. Experiment 2 found, for experienced players only, that performance was impaired following the three tasks described above, when compared with reading or global Navon tasks. It is suggested that the three tasks affect skilled performance by provoking a shift from automatic behavior to a more analytic style. By demonstrating similarities between effects in face recognition and sporting behavior, it is hoped to better understand concepts in both fields.

  6. A study of the condensation of a high-velocity vapor jet on a coflowing turbulent liquid jet

    Science.gov (United States)

    Ovsiannikov, V. A.; Levin, A. A.

    A method for the experimental determination of the local value of the heat transfer coefficient under conditions of jet condensation is proposed which employs a heat balance expression in differential form. The method is used in an experimental study of the heat transfer characteristics of the condensation of a high-velocity coaxial jet of a slightly superheated (3 percent) steam on a coflowing cylindrical turbulent water jet. In the experiment, the relative velocities reach hundreds of m/s; the temperature nonequilibrium of the phases is high, as is the steam flow mass density during the initial contact; heat transfer between the phases is significant. The results can be used as the basis for determining experimental criterial dependences for jet condensation.

  7. Decay of non-equilibrium polariton condensate in semiconductors

    International Nuclear Information System (INIS)

    Beloussov, I.V.; Shvera, Y.M.

    1993-08-01

    Excitation dynamics of polariton quantum fluctuations arising in direct-gap semi-conductor as a result of parametric decay of non-equilibrium polariton condensate with non-zero wave vector is studied. The predominant mechanism of polariton scattering is supposed to be exciton-exciton interaction. Steady state which corresponds to the case of dynamic equilibrium between the polariton condensate and quantum fluctuations is obtained. Distribution functions of non-condensate polaritons are localized in the resonant regions, corresponding to two-particle excitation of polaritons from the condensate. The spectrum of elementary excitations in steady state coincides with usual polariton energy with the shift proportional to initial density of polariton condensate. (author). 25 refs

  8. Implementation and validation of a condensation model in ANSYS

    International Nuclear Information System (INIS)

    Lehmkuhl, J.; Kelm, S.; Allelein, H.J.; Forschungszentrum Juelich

    2012-01-01

    During design-based beyond-design accidents large amounts of steam and hydrogen are released onto the containment. The knowledge on the local distribution of gases and atmospheric conditions is therefore necessary for the design of safety systems or emergency measures. Condensation processes have a significant influence on the thermal hydraulics, the hydrogen combustion and the aerosol behavior in the containment. The presented one-phase condensation model was developed for an effective CFD modeling of condensation processes in ANSYS CFX for accident analyses. Based on the assumption that wall condensation is mainly determined by the mass transport the assumption of thermal equilibrium can be used for one-phase calculations. The modeling concept is applicable for wall and volume condensation and has been implemented.

  9. Assessment and improvement of condensation model in RELAP5/MOD3

    Energy Technology Data Exchange (ETDEWEB)

    Rho, Hui Cheon; Choi, Kee Yong; Park, Hyeon Sik; Kim, Sang Jae [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Lee, Sang Il [Korea Power Engineering Co., Inc., Seoul (Korea, Republic of)

    1997-07-15

    The objective of this research is to remove the uncertainty of the condensation model through the assessment and improvement of the various heat transfer correlations used in the RELAP5/MOD3 code. The condensation model of the standard RELAP5/MOD3 code is systematically arranged and analyzed. A condensation heat transfer database is constructed from the previous experimental data on various condensation phenomena. Based on the constructed database, the condensation models in the code are assessed and improved. An experiment on the reflux condensation in a tube of steam generator in the presence of noncondensable gases is planned to acquire the experimental data.

  10. SEA in local land use planning - first experience in the Alpine States

    International Nuclear Information System (INIS)

    Jiricka, Alexandra; Proebstl, Ulrike

    2008-01-01

    In the Alpine area, planning decisions can result in far-reaching consequences because of the high sensitivity of the Alpine ecosystems. This article is based on two hypotheses: (1) The Alpine states/regions were aware of their sensitive environment and therefore recognized the necessity of introducing a comparable instrument to assess local land use planning. (2) By introducing this differentiated assessment tool, namely SEA, an increase in costs may be the consequence. However, better and more transparent planning can contribute to the enhancement of planning standards. To reveal the validity of these assumptions the legal implementation in the Alpine countries Austria, Germany, Italy and France was examined as well as first practical experience resulting from the determined procedures. The results of the implementation process in the four states were compared and discussed on the basis of selected process steps of SEA

  11. Highlight report local initiatives. Experiences with electric transport; Highlight report lokale initiatieven. Ervaringen met elektrisch vervoer

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-15

    In March 2013 Linkingreen and XTNT started a survey on local electric transportation initiatives. The aim is to learn from the experiences, problems and obstacles of business users of electric vehicles: cars, vans or trucks, scooters, boats and special vehicles (e.g. garbage trucks) that are all-electric or plug-in (with plug). In this brief report, the main results are presented [Dutch] In maart 2013 is door Linkingreen en XTNT in opdracht van Agentschap NL een enquete uitgezet naar lokale initiatieven elektrisch vervoer. Doel is te leren wat de ervaringen, knelpunten en belemmeringen zijn van zakelijke gebruikers van elektrisch vervoer: personenauto's, bestel- of vrachtauto's, scooters, vaartuigen en bijzondere voertuigen (vuilniswagens etc.) die volledig elektrische of plug in (met stekker) zijn. In dit korte verslag zijn de belangrijkste resultaten opgenomen.

  12. The FSM technology -- Operational experience and improvements in local corrosion analysis

    International Nuclear Information System (INIS)

    Stroemmen, R.; Horn, H.; Gartland, P.O.; Wold, K.

    1996-01-01

    FSM (Field Signature Method) is a non-intrusive monitoring technique based on a patented principle, developed for the purpose of detection and monitoring of both general and localized corrosion, erosion and cracking in steel and metal structures, piping systems and vessels. Since 1991 FSM has been used for a wide range of applications e.g. for buried and open pipelines, process piping offshore, subsea pipelines and flowlines, applications in the nuclear power industry and in materials research in general. This paper describes typical applications of the FSM technology, and presents operational experience from some of the landbased and subsea installations. The paper also describes recent enhancements in the FSM technology and in the analysis of FSM readings, allowing for monitoring and detailed quantification of pitting and mesa corrosion, and of corrosion in welds

  13. Ormiaochracea as a Model Organism in Sound Localization Experiments and in Inventing Hearing Aids.

    Directory of Open Access Journals (Sweden)

    - -

    1998-09-01

    Full Text Available Hearing aid prescription for patients suffering hearing loss has always been one of the main concerns of the audiologists. Thanks to technology that has provided Hearing aids with digital and computerized systems which has improved the quality of sound heard by hearing aids. Though we can learn from nature in inventing such instruments as in the current article that has been channeled to a kind of fruit fly. Ormiaochracea is a small yellow nocturnal fly, a parasitoid of crickets. It is notable because of its exceptionally acute directional hearing. In the current article we will discuss how it has become a model organism in sound localization experiments and in inventing hearing aids.

  14. Las Cumbres Observatory Partners With Local Museums In “Experience The Eclipse” Community Program

    Science.gov (United States)

    Greenstreet, Sarah; Seale, Sandy; Rivera, Javier; Skinner, Ron

    2017-10-01

    Las Cumbres Observatory (LCO) in Goleta, California, together with the Santa Barbara Museum of Natural History (SBMNH) and the Wolf Museum of Exploration & Innovation (MOXI) put together a community program called “Experience the Eclipse” for the month of August.The greater Santa Barbara community includes over 200,000 people and the city is known for its vibrant cultural life. Events featuring science, physics, and astronomy are very popular. In 2016, Javier Rivera, the Astronomy Program Manager of the SBMNH, and Ron Skinner, the Director of Education at MOXI, met with LCO to discuss planning a month of activities to educate the public about the Great American Eclipse. The vision was to capitalize on the strength of each organization and to share information and events.The events included daily planetarium shows and open houses at the observatory of the SBMNH. All three organizations gave parties at public venues with presentations by astronomers. Together the group purchased 6,000 pairs of eclipse viewer glasses and they shared the responsibility of distributing these to local schools and community groups. A master calendar of the events was published in local press outlets and a document describing the eclipse and safe viewing practices was distributed widely. Preparation of these materials was a joint effort among the three institutions.“Experience the Eclipse” was a great success. The open houses at SBMNH were well attended and all public events sold out very quickly. On August 21, the SBMNH presented a live feed of the eclipse taken from their own observatory.We will present photos and videos from these events, along with data on the attendance and quotes from enthusiastic participants.

  15. Local drug delivery - the early Berlin experience: single drug administration versus sustained release.

    Science.gov (United States)

    Speck, Ulrich; Scheller, Bruno; Rutsch, Wolfgang; Laule, Michael; Stangl, Verena

    2011-05-01

    Our initial investigations into restenosis inhibition by local drug delivery were prompted by reports on an improved outcome of coronary interventions, including a lower rate of target lesion revascularisation, when the intervention was performed with an ionic instead of non-ionic contrast medium. Although this was not confirmed in an animal study, the short exposure of the vessel wall to paclitaxel dissolved in contrast agent or coated on balloons proved to be efficacious. A study comparing three methods of local drug delivery to the coronary artery in pigs indicated the following order of efficacy in inhibiting neointimal proliferation: paclitaxel-coated balloons > sirolimus-eluting stents, sustained drug release > paclitaxel in contrast medium. Cell culture experiments confirmed that cell proliferation can be inhibited by very short exposure to the drug. Shorter exposure times require higher drug concentrations. Effective paclitaxel concentrations in porcine arteries are achieved when the drug is dissolved in contrast medium or coated on balloons. Paclitaxel is an exceptional drug in that it stays in the treated tissue for a long time. This may explain the long-lasting efficacy of paclitaxel-coated balloons, but does not disprove the hypothesis that the agent blocks a process initiating long-lasting excessive neointimal proliferation, which occurs early after vessel injury.

  16. Development of an Acoustic Localization Method for Cavitation Experiments in Reverberant Environments

    Science.gov (United States)

    Ranjeva, Minna; Thompson, Lee; Perlitz, Daniel; Bonness, William; Capone, Dean; Elbing, Brian

    2011-11-01

    Cavitation is a major concern for the US Navy since it can cause ship damage and produce unwanted noise. The ability to precisely locate cavitation onset in laboratory scale experiments is essential for proper design that will minimize this undesired phenomenon. Measuring the cavitation onset is more accurately determined acoustically than visually. However, if other parts of the model begin to cavitate prior to the component of interest the acoustic data is contaminated with spurious noise. Consequently, cavitation onset is widely determined by optically locating the event of interest. The current research effort aims at developing an acoustic localization scheme for reverberant environments such as water tunnels. Currently cavitation bubbles are being induced in a static water tank with a laser, allowing the localization techniques to be refined with the bubble at a known location. The source is located with the use of acoustic data collected with hydrophones and analyzed using signal processing techniques. To verify the accuracy of the acoustic scheme, the events are simultaneously monitored visually with the use of a high speed camera. Once refined testing will be conducted in a water tunnel. This research was sponsored by the Naval Engineering Education Center (NEEC).

  17. Does Local Label Bias Consumer Taste Bud and Preference: Evidence of a Strawberry Sensory Experiment

    OpenAIRE

    He, Chenyi; Gao, Zhifeng; Sims, Charles A.; Zhao, Xin

    2015-01-01

    Demand for local food, particularly for fresh vegetable and fruits, keeps increasing. Consumer claimed reasons of purchasing local food often include that local food are fresher, more environmental friendly and can support local community, which implies that the local information can affect consumer’ perception of food quality. Previous research mainly focused on the impact of local information/label on consumer preference as a credence attribute that is not observable even after purchasing t...

  18. Free convective condensation in a vertical enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R.J.; Peterson, P.F. [Univ. of California, Berkeley, CA (United States); Corradini, M.L.; Pernsteiner, A.P. [Univ. of Wisconsin, Madison, WI (United States)

    1995-09-01

    Free convective condensation in a vertical enclosure was studied numerically and the results were compared with experiments. In both the numerical and experimental investigations, mist formation was observed to occur near the cooling wall, with significant droplet concentrations in the bulk. Large recirculation cells near the end of the condensing section were generated as the heavy noncondensing gas collecting near the cooling wall was accelerated downward. Near the top of the enclosure the recirculation cells became weaker and smaller than those below, ultimately disappearing near the top of the condenser. In the experiment the mist density was seen to be highest near the wall and at the bottom of the condensing section, whereas the numerical model predicted a much more uniform distribution. The model used to describe the formation of mist was based on a Modified Critical Saturation Model (MCSM), which allows mist to be generated once the vapor pressure exceeds a critical value. Equilibrium, nonequilibrium, and MCSM calculations were preformed, showing the experimental results to lie somewhere in between the equilibrium and nonequilibrium predictions of the numerical model. A single adjustable constant (indicating the degree to which equilibrium is achieved) is used in the model in order to match the experimental results.

  19. Condensation of vapor bubble in subcooled pool

    Science.gov (United States)

    Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

    2017-02-01

    We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

  20. The condensed matter physics

    International Nuclear Information System (INIS)

    Sapoval, B.

    1988-01-01

    The 1988 progress report of the laboratory of the Condensed Matter Physics (Polytechnic School, France), is presented. The Laboratory activities are related to the physics of semiconductors and disordered phases. The electrical and optical properties of the semiconductors, mixed conductor, superionic conductors and ceramics, are studied. Moreover, the interfaces of those systems and the sol-gel inorganic polymerization phenomena, are investigated. The most important results obtained, concern the following investigations: the electrochemical field effect transistor, the cathodoluminescence, the low energy secondary electrons emission, the fluctuations of a two-dimensional diffused junction and the aerogels [fr

  1. Topology in Condensed Matter

    CERN Document Server

    Monastyrsky, M I

    2006-01-01

    This book reports new results in condensed matter physics for which topological methods and ideas are important. It considers, on the one hand, recently discovered systems such as carbon nanocrystals and, on the other hand, new topological methods used to describe more traditional systems such as the Fermi surfaces of normal metals, liquid crystals and quasicrystals. The authors of the book are renowned specialists in their fields and present the results of ongoing research, some of it obtained only very recently and not yet published in monograph form.

  2. Air condensation plants

    International Nuclear Information System (INIS)

    Kelp, F.; Pohl, H.H.

    1978-01-01

    In this plant the steam is distributed by a ventilator from the bottom to symmetrically fixed, inclined cooling elements with tubes. The upper part of the current side of the cooling elements as well as the bottom part of the outflow side can be covered by cover plates via a control circuit. This way, part of the air amount is deviated and in case of unfavourable atmospheric conditions (cold) the air is heated. This heating is enough to prevent freezing of the condensate on the cooling tubes. (DG) [de

  3. Locally advanced prostatic cancer: experience with combined pelvic external beam irradiation and interstitial thermobrachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Hancock, Steven L; Kapp, Daniel S; Goffinet, Don R; Prionas, Stavros; Cox, Richard S; Bagshaw, Malcolm A

    1995-07-01

    90 did not correlate significantly with either the rate of de cline in PSA or PSA trend. Side effects included penile dysesthesia or anesthesia in 5 patients, subsequent transurethral resections for prostatic necrosis, bladder ulceration, or stricture in 3 patients, lymphedema in 2 patients, and minor urinary incontinence in 5 patients. Most patients reported erectile impotence after treatment. Conclusions: Adequate hyperthermia remains difficult to achieve within the prostate gland. The limited experience in this series does not support a thermal dose-response. Although only 4 patients have experienced recurrence within the prostate gland, the frequency of distant recurrence among these patients with locally advanced disease obscures evaluation of this endpoint. This treatment regimen approaches local tissue tolerance and its results suggests that there will be limited overall gains from dose-escalation strategies for advanced prostatic cancer.

  4. Munition Burial by Local Scour and Sandwaves: large-scale laboratory experiments

    Science.gov (United States)

    Garcia, M. H.

    2017-12-01

    Our effort has been the direct observation and monitoring of the burial process of munitions induced by the combined action of waves, currents and pure oscillatory flows. The experimental conditions have made it possible to observe the burial process due to both local scour around model munitions as well as the passage of sandwaves. One experimental facility is the Large Oscillating Water Sediment Tunnel (LOWST) constructed with DURIP support. LOWST can reproduce field-like conditions near the sea bed. The second facility is a multipurpose wave-current flume which is 4 feet (1.20 m) deep, 6 feet (1.8 m) wide, and 161 feet (49.2 m) long. More than two hundred experiments were carried out in the wave-current flume. The main task completed within this effort has been the characterization of the burial process induced by local scour as well in the presence of dynamic sandwaves with superimposed ripples. It is found that the burial of a finite-length model munition (cylinder) is determined by local scour around the cylinder and by a more global process associated with the formation and evolution of sandwaves having superimposed ripples on them. Depending on the ratio of the amplitude of these features and the body's diameter (D), a model munition can progressively get partially or totally buried as such bedforms migrate. Analysis of the experimental data indicates that existing semi-empirical formulae for prediction of equilibrium-burial-depth, geometry of the scour hole around a cylinder, and time-scales developed for pipelines are not suitable for the case of a cylinder of finite length. Relative burial depth (Bd / D) is found to be mainly a function of two parameters. One is the Keulegan-Carpenter number, KC, and the Shields parameter, θ. Munition burial under either waves or combined flow, is influenced by two different processes. One is related to the local scour around the object, which takes place within the first few hundred minutes of flow action (i.e. short

  5. Experimental studies on condensation of steam mixed with noncondensable gas inside the vertical tube in a pool filled with subcooled water

    International Nuclear Information System (INIS)

    Maheshwari, N.K.; Saha, D.; Sinha, R.K.; Aritomi, M.

    2003-01-01

    A passive containment cooling system with immersed condensers has been proposed as one of the alternatives for the advanced heavy water reactor (AHWR) being designed in India. The system removes residual/decay heat released into the containment through the immersed condensers kept in a pool of water following loss of coolant accident. An important aspect of the immersed condensers is the potential degradation of its performance due to the presence of noncondensable gases. Experiments are performed to obtain reliable data on condensation phenomena in presence of air. These experiments are conducted on full-scale tubes of condensers immersed in a pool of water maintaining similar conditions as in the prototype of AHWR. A method has been proposed for the determination of the local heat transfer rate using correlations given in literature. The parametric effects of air mass fraction, pressure, steam flow, etc. on condensation heat transfer in presence of noncondensable gas have been studied. The experimental results are compared with the correlations given in literature. (orig.)

  6. Effects of non-condensable gas on the condensation of steam

    International Nuclear Information System (INIS)

    Jackson, J.D.; An, P.; Reinert, A.; Ahmadinejad, M.

    2000-01-01

    The experimental work reported here was undertaken with the aim of extending the database currently available on the condensation of steam in the presence of non-condensable gases and thereby improving the empirical input to thermal-hydraulic codes which might be used for design and safety assessment of advanced water-cooled nuclear reactors. Heat was removed from flowing mixtures of steam and air in a test section by means of a water-cooled condensing plate. The test facility constructed for the study incorporates a degassing unit which supplies water to a boiler. This delivers steam steadily to a mixing chamber where it joins with a flow of preheated air. The mixture of steam and air is supplied to the bottom of a cylindrical test section in which it flows upwards over a double sided condensing plate which can be vertical, inclined or horizontal, The rate at which heat is removed by cooling water flowing through internal passages in the plate can de determined calorimetrically knowing the flow rate of the water and its temperature rise. After commissioning experiments had shown that reliable measurements of condensation heat transfer rate could be made using the test facility, a programme of development work followed in the course of which three different designs of condensing plate were evaluated in turn. The version eventually used in the main programme of experiments which followed was made from copper. However, its surfaces were coated with a thin layer of nickel and then with one of chromium. It was found that such a surface consistently promoted dropwise condensation and showed no signs of deterioration after lengthy periods of use. The rate of heat removal from pure steam and from mixtures of steam and air in varying proportions was measured as a function of plate sub-cooling for a variety of plate orientations. (author)

  7. Condensation Analysis of Steam/Air Mixtures in Horizontal Tubes

    International Nuclear Information System (INIS)

    Lee, Kwon Yeong; Bae, Sung Won; Kim, Moo Hwan

    2008-01-01

    Perhaps the most common flow configuration in which a convective condensation occurs is a flow in a horizontal circular tube. This configuration is encountered in air-conditioning and refrigeration condensers as well as condensers in Rankine power cycles. Although a convective condensation is also sometimes contrived to occur in a co-current vertical downward flow, a horizontal flow is often preferred because the flow can be repeatedly passed through the heat exchanger core in a serpentine fashion without trapping liquid or vapor in the return bends. Many researchers have investigated a in-tube condensation for horizontal heat exchangers. However, almost all of them obtained tube section-averaged data without a noncondensable gas. Recently, Wu and Vierow have experimentally studied the condensation of steam in a horizontal heat exchanger with air present. In order to measure the condenser tube inner surface temperatures and to calculate the local heat fluxes, they developed an innovative thermocouple design that allowed for nonintrusive measurements. Here we developed a theoretical model using the heat and mass analogy to analyze a steam condensation with a noncondensable gas in horizontal tubes

  8. Bose-Einstein condensation and indirect excitons: a review.

    Science.gov (United States)

    Combescot, Monique; Combescot, Roland; Dubin, François

    2017-06-01

    We review recent progress on Bose-Einstein condensation (BEC) of semiconductor excitons. The first part deals with theory, the second part with experiments. This Review is written at a time where the problem of exciton Bose-Einstein condensation has just been revived by the understanding that the exciton condensate must be dark because the exciton ground state is not coupled to light. Here, we theoretically discuss this missed understanding before providing its experimental support through experiments that scrutinize indirect excitons made of spatially separated electrons and holes. The theoretical part first discusses condensation of elementary bosons. In particular, the necessary inhibition of condensate fragmentation by exchange interaction is stressed, before extending the discussion to interacting bosons with spin degrees of freedom. The theoretical part then considers composite bosons made of two fermions like semiconductor excitons. The spin structure of the excitons is detailed, with emphasis on the crucial fact that ground-state excitons are dark: indeed, this imposes the exciton Bose-Einstein condensate to be not coupled to light in the dilute regime. Condensate fragmentations are then reconsidered. In particular, it is shown that while at low density, the exciton condensate is fully dark, it acquires a bright component, coherent with the dark one, beyond a density threshold: in this regime, the exciton condensate is 'gray'. The experimental part first discusses optical creation of indirect excitons in quantum wells, and the detection of their photoluminescence. Exciton thermalisation is also addressed, as well as available approaches to estimate the exciton density. We then switch to specific experiments where indirect excitons form a macroscopic fragmented ring. We show that such ring provides efficient electrostatic trapping in the region of the fragments where an essentially-dark exciton Bose-Einstein condensate is formed at sub-Kelvin bath

  9. Quantum condensation from a tailored exciton population in a microcavity

    International Nuclear Information System (INIS)

    Eastham, P. R.; Phillips, R. T.

    2009-01-01

    An experiment is proposed on the coherent quantum dynamics of a semiconductor microcavity containing quantum dots. Modeling the experiment using a generalized Dicke model, we show that a tailored excitation pulse can create an energy-dependent population of excitons, which subsequently evolves to a quantum condensate of excitons and photons. The population is created by a generalization of adiabatic rapid passage and then condenses due to a dynamical analog of the BCS instability.

  10. Ice condenser experimental plan

    International Nuclear Information System (INIS)

    Kannberg, L.D.; Piepel, G.F.; Owczarski, P.C.; Liebetrau, A.M.

    1986-01-01

    An experimental plan is being developed to validate the computer code ICEDF. The code was developed to estimate the extent of aerosol retention in the ice compartments of pressurized water reactor ice condenser containment systems during severe accidents. The development of the experimental plan began with review of available information on the conditions under which the code will be applied. Computer-generated estimates of thermohydraulic and aerosol conditions entering the ice condenser were evaluated and along with other information, used to generate design criteria. The design criteria have been used for preliminary test assembly design and for generation of statistical test designs. Consideration of the phenomena to be evaluated in the testing program, as well as equipment and measurement limitations, have led to changes in the design criteria and to subsequent changes in the test assembly design and statistical test design. The overall strategy in developing the experimental plan includes iterative generation and evaluation of candidate test designs using computer codes for statistical test design and ICEDF for estimation of experimental results. Estimates of experimental variability made prior to actual testing will be verified by replicate testing at preselected design points

  11. Condensation heat transfer of R22 and R410A in horizontal smooth and microfin tubes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Man-Hoe; Shin, Joeng-Seob [Korea Advanced Institute of Science and Technology, Daejeon (Korea). Department of Mechanical Engineering

    2005-09-01

    An experimental investigation of condensation heat transfer in 9.52 mm O.D. horizontal copper tubes was conducted using R22 and R410A. The test rig had a straight, horizontal test section with an active length of 0.92 m and was cooled by the heat transfer fluid (cold water) circulated in a surrounding annulus. Constant heat flux of 11.0 kW/m{sup 2} was maintained throughout the experiment and refrigerant quality varied from 0.9 to 0.1. The condensation test results at 45 {sup o}C were reported for 40-80 kg/h mass flow rate. The local and average condensation coefficients for seven microfin tubes were presented compared to those for a smooth tube. The average condensation coefficients of R22 and R410A for the microfin tubes were 1.7-3.19 and 1.7-2.94 times larger than those in smooth tube, respectively. (author)

  12. A model for the performance of a vertical tube condenser in the presence of noncondensable gases

    Energy Technology Data Exchange (ETDEWEB)

    Guentay, A.D.S.

    1995-09-01

    Some proposed vertical tube condensers are designed to operate at high noncondensable fractions, which warrants a simple model to predict their performance. Models developed thus far are usually non self-contained as they require the specification of the wall temperature to predict the local condensation rate. The present model attempts to fill this gap by addressing the secondary side heat transfer as well. Starting with momentum balance which includes the effect of interfacial shear stress, a Nusselt-type algebraic equation is derived for the film thickness as a function of flow and geometry parameters. The heat and mass transfer analogy relations are then invoked to deduce the condensation rate of steam onto the tube wall. Lastly, the heat transfer to the secondary side is modelled to include cooling by forced, free or mixed convection flows. The model is used for parametric simulations to determine the impact on the condenser performance of important factors such as the inlet gas fraction, the mixture inlet flowrate, the total pressure, and the molecular weight of the noncondensable gas. The model performed simulations of some experiments with pure steam and air-steam mixtures flowing down a vertical tube. The model predicts the data quite well.

  13. Gravitino Condensates in the Early Universe and Inflation

    CERN Document Server

    Mavromatos, Nick E

    2015-01-01

    We review work on the formation of gravitino condensates via the super-Higgs effect in the early Universe. This is a scenario for both inflating the early universe and breaking local supersymmetry (supergravity), entirely independent of any coupling to external matter. The goldstino mode associated with the breaking of (global) supersymmetry is "eaten" by the gravitino field, which becomes massive (via its own vacuum condensation) and breaks the local supersymmetry (supergravity) dynamically. The most natural association of gravitino condensates with inflation proceeds in an indirect way, via a Starobinsky-inflation-type phase. The higher-order curvature corrections of the (quantum) effective action of gravitino condensates induced by integrating out massive gravitino degrees of freedom in a curved space-time background, in the broken-supergravity phase, are responsible for inducing a scalar mode which inflates the Universe. The scenario is in agreement with Planck data phenomenology in a natural and phenomen...

  14. Recondensation phenomena of a hot two-phase fluid in the presence of non condensable gases

    International Nuclear Information System (INIS)

    Berthoud, G.

    1983-09-01

    The condensation rates obtained during the expansion of a large hot bubble containing non condensable gases in its cold liquid is studied. The failure of theories derived from the Nusselt model for liquid metals led to use the kinetic theory of condensation. The additionnal resistance due to the presence of non condensable gases is expressed by the vapor diffusion through the layer of gases which accumulates at the interface. This model is then used to interprete experiments [fr

  15. Optimal design of condenser volume in nuclear power plant

    International Nuclear Information System (INIS)

    Zheng Jing; Yan Changqi; Wang Jianjun

    2011-01-01

    The condenser is an important component in the nuclear power plant,whose dimension will influence the economy and the arrangement of the nuclear power plant.In this paper, the calculation model was established according to the design experience. The corresponding codes were also developed. The sensitivity of design parameters which influence the condenser Janume was analyzed. The present optimal design of the condenser, aiming at the volume minimization, was carried out with the self-developed complex-genetic algorithm. The results show that the reference condenser design is far from the best scheme. In addition, the results also verify the feasibility of the complex-genetic algorithm. Furthermore, the results of this paper can provide reference for the design of the condenser. (authors)

  16. Confinement and Local Transport in the National Spherical Torus Experiment NSTX

    International Nuclear Information System (INIS)

    Kaye, S.M.; Levinton, F.M.; Stutman, D.; Tritz, K.; Yuh, H.; Bell, M.G.; Bell, R.E.; Domier, C.W.; Gates, D.; Horton, W.; Kim, J.; LeBlanc, B.P.; Luhmann, N.C. Jr.; Maingi, T.; Mazzucato, E.; Menard, J.E.; Mikkelsen, D.; Mueller, D; Park, H.; Rewoldt, G.; Sabbagh, S.A.; Smith, D.R.; Wang, W.

    2007-01-01

    NSTX operates at low aspect ratio (R/a∼1.3) and high beta (up to 40%), allowing tests of global confinement and local transport properties that have been established from higher aspect ratio devices. NSTX plasmas are heated by up to 7 MW of deuterium neutral beams with preferential electron heating as expected for ITER. Confinement scaling studies indicate a strong B T dependence, with a current dependence that is weaker than that observed at higher aspect ratio. Dimensionless scaling experiments indicate a strong increase of confinement with decreasing collisionality and a weak degradation with beta. The increase of confinement with B T is due to reduced transport in the electron channel, while the improvement with plasma current is due to reduced transport in the ion channel related to the decrease in the neoclassical transport level. Improved electron confinement has been observed in plasmas with strong reversed magnetic shear, showing the existence of an electron internal transport barrier (eITB). The development of the eITB may be associated with a reduction in the growth of microtearing modes in the plasma core. Perturbative studies show that while L-mode plasmas with reversed magnetic shear and an eITB exhibit slow changes of L Te across the profile after the pellet injection, H-mode plasmas with a monotonic q-profile and no eITB show no change in this parameter after pellet injection, indicating the existence of a critical gradient that may be related to the q-profile. Both linear and non-linear simulations indicate the potential importance of ETG modes at the lowest B T . Localized measurements of high-k fluctuations exhibit a sharp decrease in signal amplitude levels across the L-H transition, associated with a decrease in both ion and electron transport, and a decrease in calculated linear microinstability growth rates across a wide k-range, from the ITG/TEM regime up to the ETG regime

  17. Local experience with extracorporeal membrane oxygenation in children with acute fulminant myocarditis.

    Directory of Open Access Journals (Sweden)

    Botao Ning

    Full Text Available To analyze the clinical effect of extracorporeal membrane oxygenation (ECMO in children with acute fulminant myocarditis, we retrospectively analyzed the data of five children with acute fulminant myocarditis in the intensive care unit (ICU at the Affiliated Children's Hospital, Zhejiang University from February 2009 to November 2012. The study group included two boys and three girls ranging in age from 9 to 13 years (median 10 years. Body weight ranged from 25 to 33 kg (mean 29.6 kg. They underwent extracorporeal membrane oxygenation (ECMO through a venous-arterial ECMO model with an average ECMO supporting time of 89.8 h (40-142 h. Extracorporeal circulation was established in all five children. After treatment with ECMO, the heart rate, blood pressure, and oxygen saturation were greatly improved in the four children who survived. These four children were successfully weaned from ECMO and discharged from hospital machine-free, for a survival rate of 80% (4/5. One child died still dependent on the machine. Cause of death was irrecoverable cardiac function and multiple organ failure. Complications during ECMO included three cases of suture bleeding, one case of acute hemolytic renal failure and suture bleeding, and one case of hyperglycemia. During the follow-up period of 4-50 months, the four surviving children recovered with normal cardiac function and no abnormal functions of other organs. The application of ECMO in acute fulminant myocarditis, even in local centers that experience low incidence of this disease, remains an effective approach. Larger studies to determine optimal timing of placement on ECMO to guide local centers are warranted.

  18. Quantum tunneling of Bose-Einstein condensates in optical lattices

    CERN Document Server

    Fan Wen Bin

    2003-01-01

    In quantum tunneling a particle with energy E can pass through a high potential barrier V(>E) due to the wave character of the particle. Bose-Einstein condensates can display very strong tunneling depending on the structure of the trap, which may be a double-well or optical lattices. The employed for the first time to our knowledge the periodic instanton method to investigate tunneling of Bose-Einstein condensates in optical lattices. The results show that there are two kinds of tunneling in this system, Landau-Zener tunneling between extended states of the system and Wannier-Stark tunneling between localized states of the system, and that the latter is 1000 times faster than the former. The also obtain the total decay rate for a wide range of temperature, including classical thermal activation, thermally assisted tunneling and quantum tunneling. The results agree with experimental data in references. Finally, the propose an experimental protocol to observe this new phenomenon in future experiments

  19. Academic performance and personal experience of local, international, and collaborative exchange students enrolled in an Australian pharmacy program.

    Science.gov (United States)

    Davey, Andrew K; Grant, Gary D; Anoopkumar-Dukie, Shailendra

    2013-09-12

    To assess the academic performance and experiences of local, international, and collaborative exchange students enrolled in a 4-year Australian bachelor of pharmacy degree program. Survey instruments exploring the demographics, background, and academic and cultural experiences of students during the program were administered in 2005 to students in all 4 years. Additionally, grades from each semester of the program for students (406 local, 70 international, 155 exchange) who graduated between 2002 and 2006 were analyzed retrospectively. The main differences found in the survey responses among the 3 groups were in students' motivations for choosing the degree program and school, with international and collaborative exchange students having put more thought into these decisions than local students. The average grades over the duration of the program were similar in all 3 demographic groups. However, local students slightly outperformed international students, particularly at the start of the year, whereas collaborative exchange students' grades mirrored those of local students during the 2 years prior to leaving their home country of Malaysia but more closely mirrored those of international students in the final 2 years after arriving on campus in Australia. Despite differences in academic backgrounds and culture, international and exchange students can perform well compared to local students in a bachelor of pharmacy program and were actually more satisfied than local students with the overall experience. Studying in a foreign country can negatively influence academic grades to a small extent and this is probably related to adjusting to the new environment.

  20. Effect of design and operation parameters on heat transfer coefficient in condensers

    International Nuclear Information System (INIS)

    Eskin, N.; Arslan, G.; Balci, T.

    2009-01-01

    Accurate and optimum usage of energy sources is gaining importance all over the world due to the increase of energy need and limited energy sources. Increasing condenser efficiency, reduce both the dimensions and the material usage and also the investment cost of the devices. This can be maintained by increasing the heat transfer coefficient in condensers. Generally, tubes having plain inner surfaces are mounted horizontally in serpentine type condenser applications and due to the performance loss results from the congestion in serpentine connections, vertical tube mounting is not preferred. Due to the complexity of the two-phase flow, a single set of correlation for heat transfer cannot be used. Average and local heat transfer coefficient for condensers are determined. Moreover, for each experiments flow pattern is determined and the validity of the correlations are compared according to that flow pattern. In Table 2, some of the experiments for R134a are listed. Local heat transfer coefficient is also important for condenser design. As a result, to design effective condensers the accuracy of the correlations is very important. When all the experiments are taken into account, it is seen that deviation of the correlations differs according to the refrigerant type, tube dimensions, mass flux, saturation temperature and flow pattern. For high mass flux (>400 kg/m 2 s) Traviss (1973) correlation failed. For small diameters (<3.14 mm) Tandon (1985) correlation estimate the heat transfer coefficient with a high deviation. Most accurate results are obtained for Akers et al. (1959), M.M. Shah (1978), Cavallini and Zecchlin (1974), J.R. Thome - J. El Hajal - A. Cavallini (2003) correlations. For high mass flux and annular flow, M.M. Shah (1978) correlation estimates the heat transfer coefficient with high precision. However, as the tube diameter decrease, this deviation increases. For small tube diameter such as 0.691 mm Cavallini and Zecchlin (1974) gives the most

  1. Bose-Einstein Condensation

    International Nuclear Information System (INIS)

    Jaksch, D

    2003-01-01

    The Gross-Pitaevskii equation, named after one of the authors of the book, and its large number of applications for describing the properties of Bose-Einstein condensation (BEC) in trapped weakly interacting atomic gases, is the main topic of this book. In total the monograph comprises 18 chapters and is divided into two parts. Part I introduces the notion of BEC and superfluidity in general terms. The most important properties of the ideal and the weakly interacting Bose gas are described and the effects of nonuniformity due to an external potential at zero temperature are studied. The first part is then concluded with a summary of the properties of superfluid He. In Part II the authors describe the theoretical aspects of BEC in harmonically trapped weakly interacting atomic gases. A short and rather rudimentary chapter on collisions and trapping of atomic gases which seems to be included for completeness only is followed by a detailed analysis of the ground state, collective excitations, thermodynamics, and vortices as well as mixtures of BECs and the Josephson effect in BEC. Finally, the last three chapters deal with topics of more recent interest like BEC in optical lattices, low dimensional systems, and cold Fermi gases. The book is well written and in fact it provides numerous useful and important relations between the different properties of a BEC and covers most of the aspects of ultracold weakly interacting atomic gases from the point of view of condensed matter physics. The book contains a comprehensive introduction to BEC for physicists new to the field as well as a lot of detail and insight for those already familiar with this area. I therefore recommend it to everyone who is interested in BEC. Very clearly however, the intention of the book is not to provide prospects for applications of BEC in atomic physics, quantum optics or quantum state engineering and therefore the more practically oriented reader might sometimes wonder why exactly an equation is

  2. ITALIAN LOCAL PUBLIC SERVICES: SOME GOVERNANCE HIGHLIGHTS FROM THE LARGER CITIES’ EXPERIENCE

    Directory of Open Access Journals (Sweden)

    DE MATTEIS Fabio

    2013-06-01

    Full Text Available Entrusting most local public services to local government entities has led to proliferation of public groups and, consistently, to greater complexity of the governance dynamics of local authorities. Differently from Anglo-Saxon countries, the Italian local public services provision has been characterized by a hybrid externalization process where local entities are legally autonomous but owned by the local government. This leads to a peculiar governance complexity source represented by the dual role (stakeholder and customer assumed by the local authority. Considering these elements (hybrid externalization and governance structure, this work tries to investigate some governance issues of public groups, basing on the two most populous Italian municipalities. The empirical findings highlight a gap between the presence of the conditions for defining a group governance structure and the adoption of a group approach by the parent local government. The authors try to suggest how to bridge this gap.

  3. Experiences of providing prosthetic and orthotic services in Sierra Leone--the local staff's perspective.

    Science.gov (United States)

    Magnusson, Lina; Ahlström, Gerd

    2012-01-01

    In Sierra Leone, West Africa, there are many people with disabilities in need of rehabilitation services after a long civil war. The aim of this qualitative study was to explore the experiences of prosthetic and orthotic service delivery in Sierra Leone from the local staff's perspective. Fifteen prosthetic and orthotic technicians working at all the rehabilitation centres providing prosthetic and orthotic services in Sierra Leone were interviewed. The interviews were transcribed and subjected to latent content analysis. One main theme emerged: sense of inability to deliver high-quality prosthetic and orthotic services. This main theme was generated from eight sub-themes: Desire for professional development; appraisals of work satisfaction and norms; patients neglected by family; limited access to the prosthetic and orthotic services available; problems with materials and machines; low public awareness concerning disabilities; marginalisation in society and low priority on the part of government. The findings illustrated traditional beliefs about the causes of disability and that the public's attitude needs to change to include and value people with disabilities. Support from international organisations was considered necessary as well as educating more prosthetic and orthotic staff to a higher level.

  4. High-accuracy local positioning network for the alignment of the Mu2e experiment.

    Energy Technology Data Exchange (ETDEWEB)

    Hejdukova, Jana B. [Czech Technical Univ., Prague (Czech Republic)

    2017-06-01

    This Diploma thesis describes the establishment of a high-precision local positioning network and accelerator alignment for the Mu2e physics experiment. The process of establishing new network consists of few steps: design of the network, pre-analysis, installation works, measurements of the network and making adjustments. Adjustments were performed using two approaches. First is a geodetic approach of taking into account the Earth’s curvature and the metrological approach of a pure 3D Cartesian system on the other side. The comparison of those two approaches is performed and evaluated in the results and compared with expected differences. The effect of the Earth’s curvature was found to be significant for this kind of network and should not be neglected. The measurements were obtained with Absolute Tracker AT401, leveling instrument Leica DNA03 and gyrotheodolite DMT Gyromat 2000. The coordinates of the points of the reference network were determined by the Least Square Meth od and the overall view is attached as Annexes.

  5. Deliberate ignition of hydrogen-air-steam mixtures in condensing steam environments

    International Nuclear Information System (INIS)

    Blanchat, T.K.; Stamps, D.W.

    1997-05-01

    Large scale experiments were performed to determine the effectiveness of thermal glow plug igniters to burn hydrogen in a condensing steam environment due to the presence of water sprays. The experiments were designed to determine if a detonation or accelerated flame could occur in a hydrogen-air-steam mixture which was initially nonflammable due to steam dilution but was rendered flammable by rapid steam condensation due to water sprays. Eleven Hydrogen Igniter Tests were conducted in the test vessel. The vessel was instrumented with pressure transducers, thermocouple rakes, gas grab sample bottles, hydrogen microsensors, and cameras. The vessel contained two prototypic engineered systems: (1) a deliberate hydrogen ignition system and (2) a water spray system. Experiments were conducted under conditions scaled to be nearly prototypic of those expected in Advanced Light Water Reactors (such as the Combustion Engineering (CE) System 80+), with prototypic spray drop diameter, spray mass flux, steam condensation rates, hydrogen injection flow rates, and using the actual proposed plant igniters. The lack of any significant pressure increase during the majority of the burn and condensation events signified that localized, benign hydrogen deflagration(s) occurred with no significant pressure load on the containment vessel. Igniter location did not appear to be a factor in the open geometry. Initially stratified tests with a stoichiometric mixture in the top showed that the water spray effectively mixes the initially stratified atmosphere prior to the deflagration event. All tests demonstrated that thermal glow plugs ignite hydrogen-air-steam mixtures under conditions with water sprays near the flammability limits previously determined for hydrogen-air-steam mixtures under quiescent conditions. This report describes these experiments, gives experimental results, and provides interpretation of the results. 12 refs., 127 figs., 16 tabs

  6. Condensed matter physics in electrochemistry

    International Nuclear Information System (INIS)

    Kornyshev, A.A.

    1991-01-01

    Some topics in electrochemistry are considered from the condensed matter physics viewpoint in relation to the problems discussed in this book. Examples of the successful application of condensed matter physics to electrochemistry are discussed together with prospective problems and pressing questions. (author). 127 refs, 4 figs

  7. Local vibrational modes of the water dimer - Comparison of theory and experiment

    Science.gov (United States)

    Kalescky, R.; Zou, W.; Kraka, E.; Cremer, D.

    2012-12-01

    Local and normal vibrational modes of the water dimer are calculated at the CCSD(T)/CBS level of theory. The local H-bond stretching frequency is 528 cm-1 compared to a normal mode stretching frequency of just 143 cm-1. The adiabatic connection scheme between local and normal vibrational modes reveals that the lowering is due to mass coupling, a change in the anharmonicity, and coupling with the local HOH bending modes. The local mode stretching force constant is related to the strength of the H-bond whereas the normal mode stretching force constant and frequency lead to an erroneous underestimation of the H-bond strength.

  8. Differences in pollination success between local and foreign flower color phenotypes: a translocation experiment with Gentiana lutea (Gentianaceae)

    Science.gov (United States)

    Sobral, Mar; Veiga, Tania; Guitián, Pablo; Guitián, José M.

    2017-01-01

    Background The adaptive maintenance of flower color variation is frequently attributed to pollinators partly because they preferentially visit certain flower phenotypes. We tested whether Gentiana lutea—which shows a flower color variation (from orange to yellow) in the Cantabrian Mountains range (north of Spain)—is locally adapted to the pollinator community. Methods We transplanted orange-flowering individuals to a population with yellow-flowering individuals and vice versa, in order to assess whether there is a pollination advantage in the local morph by comparing its visitation rate with the foreign morph. Results Our reciprocal transplant experiment did not show clear local morph advantage in overall visitation rate: local orange flowers received more visits than foreign yellow flowers in the orange population, while both local and foreign flowers received the same visits in the yellow population; thus, there is no evidence of local adaptation in Gentiana lutea to the pollinator assemblage. However, some floral visitor groups (such as Bombus pratorum, B. soroensis ancaricus and B. lapidarius decipiens) consistently preferred the local morph to the foreign morph whereas others (such as Bombus terrestris) consistently preferred the foreign morph. Discussion We concluded that there is no evidence of local adaptation to the pollinator community in each of the two G. lutea populations studied. The consequences for local adaptation to pollinator on G. lutea flower color would depend on the variation along the Cantabrian Mountains range in morph frequency and pollinator community composition. PMID:28194308

  9. Differences in pollination success between local and foreign flower color phenotypes: a translocation experiment with Gentiana lutea (Gentianaceae

    Directory of Open Access Journals (Sweden)

    Javier A. Guitián

    2017-02-01

    Full Text Available Background The adaptive maintenance of flower color variation is frequently attributed to pollinators partly because they preferentially visit certain flower phenotypes. We tested whether Gentiana lutea—which shows a flower color variation (from orange to yellow in the Cantabrian Mountains range (north of Spain—is locally adapted to the pollinator community. Methods We transplanted orange-flowering individuals to a population with yellow-flowering individuals and vice versa, in order to assess whether there is a pollination advantage in the local morph by comparing its visitation rate with the foreign morph. Results Our reciprocal transplant experiment did not show clear local morph advantage in overall visitation rate: local orange flowers received more visits than foreign yellow flowers in the orange population, while both local and foreign flowers received the same visits in the yellow population; thus, there is no evidence of local adaptation in Gentiana lutea to the pollinator assemblage. However, some floral visitor groups (such as Bombus pratorum, B. soroensis ancaricus and B. lapidarius decipiens consistently preferred the local morph to the foreign morph whereas others (such as Bombus terrestris consistently preferred the foreign morph. Discussion We concluded that there is no evidence of local adaptation to the pollinator community in each of the two G. lutea populations studied. The consequences for local adaptation to pollinator on G. lutea flower color would depend on the variation along the Cantabrian Mountains range in morph frequency and pollinator community composition.

  10. Differences in pollination success between local and foreign flower color phenotypes: a translocation experiment with Gentiana lutea (Gentianaceae).

    Science.gov (United States)

    Guitián, Javier A; Sobral, Mar; Veiga, Tania; Losada, María; Guitián, Pablo; Guitián, José M

    2017-01-01

    The adaptive maintenance of flower color variation is frequently attributed to pollinators partly because they preferentially visit certain flower phenotypes. We tested whether Gentiana lutea -which shows a flower color variation (from orange to yellow) in the Cantabrian Mountains range (north of Spain)-is locally adapted to the pollinator community. We transplanted orange-flowering individuals to a population with yellow-flowering individuals and vice versa, in order to assess whether there is a pollination advantage in the local morph by comparing its visitation rate with the foreign morph. Our reciprocal transplant experiment did not show clear local morph advantage in overall visitation rate: local orange flowers received more visits than foreign yellow flowers in the orange population, while both local and foreign flowers received the same visits in the yellow population; thus, there is no evidence of local adaptation in Gentiana lutea to the pollinator assemblage. However, some floral visitor groups (such as Bombus pratorum , B. soroensis ancaricus and B. lapidarius decipiens ) consistently preferred the local morph to the foreign morph whereas others (such as Bombus terrestris ) consistently preferred the foreign morph. We concluded that there is no evidence of local adaptation to the pollinator community in each of the two G. lutea populations studied. The consequences for local adaptation to pollinator on G. lutea flower color would depend on the variation along the Cantabrian Mountains range in morph frequency and pollinator community composition.

  11. Off gas condenser performance modelling

    International Nuclear Information System (INIS)

    Cains, P.W.; Hills, K.M.; Waring, S.; Pratchett, A.G.

    1989-12-01

    A suite of three programmes has been developed to model the ruthenium decontamination performance of a vitrification plant off-gas condenser. The stages of the model are: condensation of water vapour, NO x absorption in the condensate, RuO 4 absorption in the condensate. Juxtaposition of these stages gives a package that may be run on an IBM-compatible desktop PC. Experimental work indicates that the criterion [HNO 2 ] > 10 [RuO 4 ] used to determine RuO 4 destruction in solution is probably realistic under condenser conditions. Vapour pressures of RuO 4 over aqueous solutions at 70 o -90 o C are slightly lower than the values given by extrapolating the ln K p vs. T -1 relation derived from lower temperature data. (author)

  12. The effect of non-condensable gas on direct contact condensation of steam/air mixture

    International Nuclear Information System (INIS)

    Lee, H. C.; Park, S. K.; Kim, M. H.

    1998-01-01

    To investigate the effects of noncondensable gas on the direct contact film condensation of vapor mixture, a series of experiments has been carried out. The rectangular duct inclined 87.deg. to the horizontal plane was used for this experiment. The average heat transfer coefficient of the steam-air mixture was obtained at the atmospheric pressure with four main parameters, air-mass fraction, vapor velocity, film Reynolds number,and the degree of water film subcooling having an influence on the condensation heat transfer coefficient. With the analysis on 88 cases of experiments, a correlation of the average Nusselt number for direct contact film condensation of steam-air mixture at a vertical wall proposed as functions of film Reynolds number, mixture Reynolds number, air mass fraction, and Jacob number. The average heat transfer coefficient for steam-air mixture condensation decreased significantly while air mass fraction increases with the same inlet mixture velocity and inlet film temperature. The average heat transfer coefficients also decreased with the degree of film subcooling increasing and were scarcely affected by film Reynolds number below the mixture Reynolds number about 30,000

  13. Morphology and Viscoelastic Properties of Polystyrene Blended with Fully Condensed Polyhedral Oligomeric Silsesquioxanes

    National Research Council Canada - National Science Library

    Namani, Madhu; Geng, Hai-Ping; Lee, Andre; Blanski, Rusty L

    2004-01-01

    .... Experiments were performed using a nearly-monodisperse molecular weight polystyrene (PS) blended with varying amounts of two fully condensed POSS molecules surrounded with phenethyl and styrenyl groups...

  14. Superfluidity, Bose condensation and neutron scattering in liquid 4He

    International Nuclear Information System (INIS)

    Silver, R.N.

    1997-01-01

    The relation between superfluidity and Bose condensation in 4 He provides lessons that may be valuable in understanding the strongly correlated electron system of high T c superconductivity. Direct observation of a Bose condensate in the superfluid by deep inelastic neutron scattering measurements has been attempted over many years. But the impulse approximation, which relates momentum distributions to neutron scattering structure functions, is broadened by final state effects. Nevertheless, the excellent quantitative agreement between ab initio quantum many body theory and high precision neutron experiments provides confidence in the connection between superfluidity and Bose condensation

  15. Enhancing Local Community’s Involvement and Empowerment through Practicing Cittaslow: Experiences from Goolwa, South Australia

    Directory of Open Access Journals (Sweden)

    Park Eerang

    2014-01-01

    Full Text Available This study attempted to investigate how and the extent to which Cittaslow philosophy and practice enhanced local community’s involvement and empowerment in relation to tourism development from the sustainability’s perspective. As an empirical study, a series of in-depth interviews with key stakeholders including local government, local business, and local community’s members were conducted in Goolwa, the first Australian accredited Cittaslow town since 2007, located in South Australia. The results indicated that to a greater extent the accreditation and practice of Cittaslow philosophy in Goolwa increased a stronger and more effective collaboration amongst local community, business and residents as an essential element for achieving sustainability in tourism development. Not only did it encourage the local community’s participation in decision making process from the beginning of tourism development, but also revitalised the locality and sense of place of Goolwa through promoting local specialities and produces, in particular food and wine products. The results also suggested that psychological and social aspects of local community’s empowerment have been significantly enhanced after the establishment of Cittaslow. Yet, the economic empowerment of the local community was less experienced.

  16. Stereotactic Body Radiation Therapy (SBRT) for clinically localized prostate cancer: the Georgetown University experience

    International Nuclear Information System (INIS)

    Chen, Leonard N; Lei, Siyuan; Batipps, Gerald P; Kowalczyk, Keith; Bandi, Gaurav

    2013-01-01

    Stereotactic body radiation therapy (SBRT) delivers fewer high-dose fractions of radiation which may be radiobiologically favorable to conventional low-dose fractions commonly used for prostate cancer radiotherapy. We report our early experience using SBRT for localized prostate cancer. Patients treated with SBRT from June 2008 to May 2010 at Georgetown University Hospital for localized prostate carcinoma, with or without the use of androgen deprivation therapy (ADT), were included in this retrospective review of data that was prospectively collected in an institutional database. Treatment was delivered using the CyberKnife® with doses of 35 Gy or 36.25 Gy in 5 fractions. Biochemical control was assessed using the Phoenix definition. Toxicities were recorded and scored using the CTCAE v.3. Quality of life was assessed before and after treatment using the Short Form-12 Health Survey (SF-12), the American Urological Association Symptom Score (AUA) and Sexual Health Inventory for Men (SHIM) questionnaires. Late urinary symptom flare was defined as an AUA score ≥ 15 with an increase of ≥ 5 points above baseline six months after the completion of SBRT. One hundred patients (37 low-, 55 intermediate- and 8 high-risk according to the D’Amico classification) at a median age of 69 years (range, 48–90 years) received SBRT, with 11 patients receiving ADT. The median pre-treatment prostate-specific antigen (PSA) was 6.2 ng/ml (range, 1.9-31.6 ng/ml) and the median follow-up was 2.3 years (range, 1.4-3.5 years). At 2 years, median PSA decreased to 0.49 ng/ml (range, 0.1-1.9 ng/ml). Benign PSA bounce occurred in 31% of patients. There was one biochemical failure in a high-risk patient, yielding a two-year actuarial biochemical relapse free survival of 99%. The 2-year actuarial incidence rates of GI and GU toxicity ≥ grade 2 were 1% and 31%, respectively. A median baseline AUA symptom score of 8 significantly increased to 11 at 1 month (p = 0.001), however returned to

  17. Methodological challenges for the large N study of local participatory experiences. Combining methods and databases

    Directory of Open Access Journals (Sweden)

    Galais, Carolina

    2012-12-01

    Full Text Available In this article we analyse the effects of different data collection strategies in the study of local participatory experiences in a region of Spain (Andalusia. We examine the divergences and similarities between the data collected using different methods, as well as the implications for the reliability of the data. We have collected participatory experiences through two parallel processes: a survey of municipalities and web content mining. The survey of municipalities used two complementary strategies: an online questionnaire and a CATI follow-up for those municipalities that had not answered our first online contact attempt. Both processes (survey and data mining were applied to the same sample of municipalities, but provided significantly different images of the characteristics of Andalusia’s participatory landscape. The goal of this work is to discuss the different types of biases introduced by each data collection procedure and their implications for substantive analyses.

    En este artículo analizamos los efectos de diferentes estrategias para la recolección de datos en el estudio de las experiencias participativas andaluzas. Examinamos para ello las diferencias y similitudes entre los datos recogidos mediante diferentes métodos, así como las implicaciones para la fiabilidad de los datos. Para ello, hemos utilizado dos procedimientos paralelos. En primer lugar, una encuesta a municipios y la minería de datos en Internet. La encuesta se realizó utilizando dos modos de administración diferentes, un cuestionario online y un cuestionario telefónico de seguimiento a los municipios que no respondieron al primer intento de contacto vía correo electrónico. Tanto la encuesta como la minería de datos fueron aplicados a la misma muestra de municipios, aunque arrojaron diferencias significativas en cuanto a las características del panorama participativo en Andalucía. El objetivo de este trabajo es discutir los diferentes tipos

  18. Experimental study of EHD pseudo-dropwise condensation

    International Nuclear Information System (INIS)

    Yabe, A.; Taketani, T.; Yoshizawa, Y.; Sunada, K.

    1991-01-01

    This paper reports that in order to realize a higher performance heat pump, an electrohydrodynamical (EHD) condenser utilizing a combination of two kinds of EHD phenomena has been researched. In this study, to maximize the augmentation effect, an experimental study has been carried out to clarify the details of an EHD pseudo-dropwise condensation. The diameter of the drops has decreased with the increase of the electric field. The condensation heat transfer coefficients have increased in proportion to the electric field strength, realizing the maximum local heat transfer coefficients of over 9000 W/m 2 K for CFC113 and over 11000W/m 2 K for HCFC123. Furthermore, the heat transfer coefficients have become the same for the same electric field strength, independent of the surface temperature of the heat transfer plate, if the amount of the falling condensate is the same

  19. Characterization of spacecraft humidity condensate

    Science.gov (United States)

    Muckle, Susan; Schultz, John R.; Sauer, Richard L.

    1994-01-01

    When construction of Space Station Freedom reaches the Permanent Manned Capability (PMC) stage, the Water Recovery and Management Subsystem will be fully operational such that (distilled) urine, spent hygiene water, and humidity condensate will be reclaimed to provide water of potable quality. The reclamation technologies currently baselined to process these waste waters include adsorption, ion exchange, catalytic oxidation, and disinfection. To ensure that the baseline technologies will be able to effectively remove those compounds presenting a health risk to the crew, the National Research Council has recommended that additional information be gathered on specific contaminants in waste waters representative of those to be encountered on the Space Station. With the application of new analytical methods and the analysis of waste water samples more representative of the Space Station environment, advances in the identification of the specific contaminants continue to be made. Efforts by the Water and Food Analytical Laboratory at JSC were successful in enlarging the database of contaminants in humidity condensate. These efforts have not only included the chemical characterization of condensate generated during ground-based studies, but most significantly the characterization of cabin and Spacelab condensate generated during Shuttle missions. The analytical results presented in this paper will be used to show how the composition of condensate varies amongst enclosed environments and thus the importance of collecting condensate from an environment close to that of the proposed Space Station. Although advances were made in the characterization of space condensate, complete characterization, particularly of the organics, requires further development of analytical methods.

  20. Condensation in Nanoporous Packed Beds.

    Science.gov (United States)

    Ally, Javed; Molla, Shahnawaz; Mostowfi, Farshid

    2016-05-10

    In materials with tiny, nanometer-scale pores, liquid condensation is shifted from the bulk saturation pressure observed at larger scales. This effect is called capillary condensation and can block pores, which has major consequences in hydrocarbon production, as well as in fuel cells, catalysis, and powder adhesion. In this study, high pressure nanofluidic condensation studies are performed using propane and carbon dioxide in a colloidal crystal packed bed. Direct visualization allows the extent of condensation to be observed, as well as inference of the pore geometry from Bragg diffraction. We show experimentally that capillary condensation depends on pore geometry and wettability because these factors determine the shape of the menisci that coalesce when pore filling occurs, contrary to the typical assumption that all pore structures can be modeled as cylindrical and perfectly wetting. We also observe capillary condensation at higher pressures than has been done previously, which is important because many applications involving this phenomenon occur well above atmospheric pressure, and there is little, if any, experimental validation of capillary condensation at such pressures, particularly with direct visualization.

  1. Synthesis of the day 'Sane dwelling and radon: how to act at the local level?' - Experiments and perspectives

    International Nuclear Information System (INIS)

    Bernier, Sandrine

    2012-01-01

    This document proposes a synthesis of contributions which addressed the knowledge about radon and regulation regarding radon, the management of the risk related to the presence of radon in dwellings and the environment, at the international level (in Switzerland, in Canada); locally implemented experiments (around Montbeliard, in Aix-en-Provence, in the Finistere district) with measurements and public information are discussed

  2. Local expert experiences and perceptions of environmentally induced migration from Bangladesh to India

    NARCIS (Netherlands)

    Stojanov, Robert; Boas, Ingrid; Kelman, Ilan; Duží, Barbora

    2017-01-01

    This study investigates local expert perceptions of the role of environmental factors, especially in terms of contemporary climate change, in population movements from Bangladesh to India. The aim is to delve into locally held understandings of the phenomenon and to gain a better understanding of

  3. Generic Regional Development Strategies from Local Stakeholders' Scenarios - an Alpine Village Experience

    Directory of Open Access Journals (Sweden)

    Wolfgang Loibl

    2010-09-01

    Full Text Available The article discusses the participatory elaboration of strategies for sustainable regional development in an Alpine tourist region in Austria to cope with global change effects evolving locally, considering climate change, economic change as well as (local societal change. Local stakeholders in an Alpine village in the Montafon region contributed in workshops to achieve the final results: participant teams conducted system analyses of the regional system to explore key elements of the region. Narrative scenarios described possible positive and negative development trends and indicated the critical issues controlling future development; 3D-images of landscape transition simulations show the consequences of certain development directions. Alternative development directions supported the local stakeholders to elaborate regional development strategies. In the end, the scientist team derived generic strategies for Alpine regions based on the locally developed strategy bundle. The article presents the intention, progress and outcome of the participatory approach and elaborates the potential to derive generic strategies from local ones and discusses the possibly occurring conflicts regarding cross-scale transfers of these local strategies. Overall, tourism was seen as a key element for future regional development, which can on the one hand derogate Alpine regions and is on the other hand threatened by climate change and diminution of landscape attractiveness. The suggested development strategies will help to cope with global change issues mitigating the negative consequences on the local society and environment.

  4. Early experience of proton beam therapy combined with chemotherapy for locally advanced oropharyngeal cancer

    International Nuclear Information System (INIS)

    Ishikawa, Youjirou; Nakamura, Tatsuya; Takada, Akinori; Takayama, Kanako; Makita, Chiyoko; Suzuki, Motohisa; Azami, Yusuke; Kikuchi, Yasuhiro; Fuwa, Nobukazu

    2013-01-01

    Between 2009 and 2012, 10 patients with advanced oropharyngeal cancer underwent proton therapy combined with chemotherapy. The initial results of this therapy were 8 complete response (CR) and 2 partial response (PR), local recurrence was detected 1 patient. Proton beam therapy combined with chemotherapy is thought to be an effective treatment for locally advanced oropharyngeal cancer. (author)

  5. Faraday waves in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Nicolin, Alexandru I.; Carretero-Gonzalez, R.; Kevrekidis, P. G.

    2007-01-01

    Motivated by recent experiments on Faraday waves in Bose-Einstein condensates we investigate both analytically and numerically the dynamics of cigar-shaped Bose-condensed gases subject to periodic modulation of the strength of the transverse confinement. We offer a fully analytical explanation of the observed parametric resonance, based on a Mathieu-type analysis of the non-polynomial Schroedinger equation. The theoretical prediction for the pattern periodicity versus the driving frequency is directly compared to the experimental data, yielding good qualitative and quantitative agreement between the two. These results are corroborated by direct numerical simulations of both the one-dimensional non-polynomial Schroedinger equation and of the fully three-dimensional Gross-Pitaevskii equation

  6. Bose-Einstein condensation and superfluidity

    CERN Document Server

    Pitaevskii, Lev

    2016-01-01

    This volume introduces the basic concepts of Bose–Einstein condensation and superfluidity. It makes special reference to the physics of ultracold atomic gases; an area in which enormous experimental and theoretical progress has been achieved in the last twenty years. Various theoretical approaches to describing the physics of interacting bosons and of interacting Fermi gases, giving rise to bosonic pairs and hence to condensation, are discussed in detail, both in uniform and harmonically trapped configurations. Special focus is given to the comparison between theory and experiment, concerning various equilibrium, dynamic, thermodynamic, and superfluid properties of these novel systems. The volume also includes discussions of ultracold gases in dimensions, quantum mixtures, and long-range dipolar interactions.

  7. Models of coherent exciton condensation

    International Nuclear Information System (INIS)

    Littlewood, P B; Eastham, P R; Keeling, J M J; Marchetti, F M; Simons, B D; Szymanska, M H

    2004-01-01

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers

  8. Models of coherent exciton condensation

    Energy Technology Data Exchange (ETDEWEB)

    Littlewood, P B [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Eastham, P R [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Keeling, J M J [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Marchetti, F M [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Simons, B D [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Szymanska, M H [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom)

    2004-09-08

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers.

  9. Bose condensation in (random traps

    Directory of Open Access Journals (Sweden)

    V.A. Zagrebnov

    2009-01-01

    Full Text Available We study a non-interacting (perfect Bose-gas in random external potentials (traps. It is shown that a generalized Bose-Einstein condensation in the random eigenstates manifests if and only if the same occurs in the one-particle kinetic-energy eigenstates, which corresponds to the generalized condensation of the free Bose-gas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.

  10. Localization of insulinomas to regions of the pancreas by intraarterial calcium stimulation: the NIH experience.

    Science.gov (United States)

    Guettier, Jean-Marc; Kam, Anthony; Chang, Richard; Skarulis, Monica C; Cochran, Craig; Alexander, H Richard; Libutti, Steven K; Pingpank, James F; Gorden, Phillip

    2009-04-01

    Selective intraarterial calcium injection of the major pancreatic arteries with hepatic venous sampling [calcium arterial stimulation (CaStim)] has been used as a localizing tool for insulinomas at the National Institutes of Health (NIH) since 1989. The accuracy of this technique for localizing insulinomas was reported for all cases until 1996. The aim of the study was to assess the accuracy and track record of the CaStim over time and in the context of evolving technology and to review issues related to result interpretation and procedure complications. CaStim was the only invasive preoperative localization modality used at our center. Endoscopic ultrasound (US) was not studied. We conducted a retrospective case review at a referral center. Twenty-nine women and 16 men (mean age, 47 yr; range, 13-78) were diagnosed with an insulinoma from 1996-2008. A supervised fast was conducted to confirm the diagnosis of insulinoma. US, computed tomography (CT), magnetic resonance imaging (MRI), and CaStim were used as preoperative localization studies. Localization predicted by each preoperative test was compared to surgical localization for accuracy. We measured the accuracy of US, CT, MRI, and CaStim for localization of insulinomas preoperatively. All 45 patients had surgically proven insulinomas. Thirty-eight of 45 (84%) localized to the correct anatomical region by CaStim. In five of 45 (11%) patients, the CaStim was falsely negative. Two of 45 (4%) had false-positive localizations. The CaStim has remained vastly superior to abdominal US, CT, or MRI over time as a preoperative localizing tool for insulinomas. The utility of the CaStim for this purpose and in this setting is thus validated.

  11. Condensation with two constraints and disorder

    Science.gov (United States)

    Barré, J.; Mangeolle, L.

    2018-04-01

    We consider a set of positive random variables obeying two additive constraints, a linear and a quadratic one; these constraints mimic the conservation laws of a dynamical system. In the simplest setting, without disorder, it is known that such a system may undergo a ‘condensation’ transition, whereby one random variable becomes much larger than the others; this transition has been related to the spontaneous appearance of non linear localized excitations in certain nonlinear chains, called breathers. Motivated by the study of breathers in a disordered discrete nonlinear Schrödinger equation, we study different instances of this problem in presence of a quenched disorder. Unless the disorder is too strong, the phase diagram looks like the one without disorder, with a transition separating a fluid phase, where all variables have the same order of magnitude, and a condensed phase, where one variable is much larger than the others. We then show that the condensed phase exhibits various degrees of ‘intermediate symmetry breaking’: the site hosting the condensate is chosen neither uniformly at random, nor is it fixed by the disorder realization. Throughout the article, our heuristic arguments are complemented with direct Monte Carlo simulations.

  12. Steam generators, turbines, and condensers. Volume six

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Volume six covers steam generators (How steam is generated, steam generation in a PWR, vertical U-tube steam generators, once-through steam generators, how much steam do steam generators make?), turbines (basic turbine principles, impulse turbines, reaction turbines, turbine stages, turbine arrangements, turbine steam flow, steam admission to turbines, turbine seals and supports, turbine oil system, generators), and condensers (need for condensers, basic condenser principles, condenser arrangements, heat transfer in condensers, air removal from condensers, circulating water system, heat loss to the circulating water system, factors affecting condenser performance, condenser auxiliaries)

  13. Realising local government visions for developing district heating: Experiences from a learning country

    International Nuclear Information System (INIS)

    Bush, Ruth E.; Bale, Catherine S.E.; Taylor, Peter G.

    2016-01-01

    District heating (DH) has an important role to play in enabling cities to transition to low-carbon heating. Although schemes are commonplace in some countries, in ‘learning countries’ where building-level technologies make up the majority of heating systems there are numerous barriers to introducing DH. Local governments are seen as key actors in helping to create a ‘shared vision’ for DH amongst stakeholders. This study uses interviews with stakeholders from a range of sectors in the UK (an example of a learning country) to examine the visions of local actors for developing DH and the types of national policy that would support local implementation of these visions. The analysis shows that in engaging with DH development local governments seek multiple types of value. Realising this value will most likely happen by taking a long-term, planned approach to development. In contrast, national government policy is geared towards techno-economic criteria and may lead to only a minority of potential sites being developed, without realisation of wider social or environmental benefits aligned to local visions. The work highlights the importance of local strategic planning, enabled by aligned national policy, in realising the full economic, environmental and social benefits of DH. - Highlights: • Local governments are key to the development of district heating (DH). • Local government-led visions of DH seek to deliver complex value. • In the UK development is led by funding and commercial factors and is not strategic. • To enable DH, national policy must align with the vision of local actors. • Social and environmental criteria must be incorporated in decision-making.

  14. Integrating watershed hydrology and economics to establish a local market for water quality improvement: A field experiment.

    Science.gov (United States)

    Uchida, Emi; Swallow, Stephen K; Gold, Arthur; Opaluch, James; Kafle, Achyut; Merrill, Nathaniel; Michaud, Clayton; Gill, Carrie Anne

    2018-04-01

    Innovative market mechanisms are being increasingly recognized as effective decision-making institutions to incorporate the value of ecosystem services into the economy. We present a field experiment that integrates an economic auction and a biophysical water flux model to develop a local market process consisting of both the supply and demand sides. On the supply side, we operate an auction with small-scale livestock owners who bid for contracts to implement site-specific manure management practices that reduce phosphorus loadings to a major reservoir. On the demand side, we implement a real money, multi-unit public good auction for these contracts with residents who potentially benefit from reduced water quality risks. The experiments allow us to construct supply and demand curves to find an equilibrium price for water quality improvement. The field experiments provide a proof-of-concept for practical implementation of a local market for environmental improvements, even for the challenging context of nonpoint pollution.

  15. Experiential Learning in Rodents: Past Experience Enables Rapid Learning and Localized Encoding in Hippocampus

    Science.gov (United States)

    Cox, Conor D.; Palmer, Linda C.; Pham, Danielle T.; Trieu, Brian H.; Gall, Christine M.; Lynch, Gary

    2017-01-01

    Humans routinely use past experience with complexity to deal with novel, challenging circumstances. This fundamental aspect of real-world behavior has received surprisingly little attention in animal studies, and the underlying brain mechanisms are unknown. The present experiments tested for transfer from past experience in rats and then used…

  16. Potentially Prebiotic Syntheses of Condensed Phosphates

    Science.gov (United States)

    Keefe, Anthony D.; Miller, Stanley L.

    1996-01-01

    In view of the importance of a prebiotic source of high energy phosphates, we have investigated a number of potentially prebiotic processes to produce condensed phosphates from orthophosphate and cyclic trimetaphosphate from tripolyphosphate. The reagents investigated include polymerizing nitriles, acid anhydrides, lactones, hexamethylene tetramine and carbon suboxide. A number of these processes give substantial yields of pyrophosphate from orthophosphate and trimetaphosphate from tripolyphosphate. Although these reactions may have been applicable in local areas, they are not sufficiently robust to have been of importance in the prebiotic open ocean.

  17. Solar engineering - a condensed course

    Energy Technology Data Exchange (ETDEWEB)

    Broman, Lars

    2011-11-15

    The document represents the material covered in a condensed two-week course focusing on the most important thermal and PV solar energy engineering topics, while also providing some theoretical background.

  18. The role of local terminologies in electronic health records. The HEGP experience.

    Science.gov (United States)

    Daniel-Le Bozec, Christel; Steichen, Olivier; Dart, Thierry; Jaulent, Marie-Christine

    2007-01-01

    Despite decades of work, there is no universally accepted standard medical terminology and no generally usable terminological tools have yet emerged. The local dictionary of concepts of the Georges Pompidou European Hospital (HEGP) is a Terminological System (TS) designed to support clinical data entry. It covers 93 data entry forms and contains definitions and synonyms of more than 5000 concepts, sometimes linked to reference terminologies such as ICD-10. In this article, we evaluate to which extend SNOMED CT could fully replace or rather be mapped to the local terminology system. We first describe the local dictionary of concepts of HEGP according to some published TS characterization framework. Then we discuss the specific role that a local terminology system plays with regards to reference terminologies.

  19. Capillary Condensation in Confined Media

    OpenAIRE

    Charlaix, Elisabeth; Ciccotti, Matteo

    2009-01-01

    28 pages - To appear in 2010 in the Handbook of Nanophysics - Vol 1 - Edited by Klaus Sattler - CRC Press; We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and...

  20. Local stress modification during in situ transmission electron microscopy straining experiments

    Czech Academy of Sciences Publication Activity Database

    Zárubová, Niva; Gemperle, Antonín; Gemperlová, Juliana

    2007-01-01

    Roč. 462, - (2007), s. 407-411 ISSN 0921-5093 R&D Projects: GA ČR GA202/04/2016 Institutional research plan: CEZ:AV0Z10100520 Keywords : in situ TEM straining, Local stress in a strained foil * local stress in a strained foil Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.457, year: 2007

  1. Building local human resources to implement SLMTA with limited donor funding: The Ghana experience.

    Science.gov (United States)

    Nkrumah, Bernard; van der Puije, Beatrice; Bekoe, Veronica; Adukpo, Rowland; Kotey, Nii A; Yao, Katy; Fonjungo, Peter N; Luman, Elizabeth T; Duh, Samuel; Njukeng, Patrick A; Addo, Nii A; Khan, Fazle N; Woodfill, Celia J I

    2014-11-03

    In 2009, Ghana adopted the Strengthening Laboratory Management Toward Accreditation (SLMTA) programme in order to improve laboratory quality. The programme was implemented successfully with limited donor funding and local human resources. To demonstrate how Ghana, which received very limited PEPFAR funding, was able to achieve marked quality improvement using local human resources. Local partners led the SLMTA implementation and local mentors were embedded in each laboratory. An in-country training-of-trainers workshop was conducted in order to increase the pool of local SLMTA implementers. Three laboratory cohorts were enrolled in SLMTA in 2011, 2012 and 2013. Participants from each cohort attended in a series of three workshops interspersed with improvement projects and mentorship. Supplemental training on internal audit was provided. Baseline, exit and follow-up audits were conducted using the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) checklist. In November 2013, four laboratories underwent official SLIPTA audits by the African Society for Laboratory Medicine (ASLM). The local SLMTA team successfully implemented three cohorts of SLMTA in 15 laboratories. Seven out of the nine laboratories that underwent follow-up audits have reached at least one star. Three out of the four laboratories that underwent official ASLM audits were awarded four stars. Patient satisfaction increased from 25% to 70% and sample rejection rates decreased from 32% to 10%. On average, $40 000 was spent per laboratory to cover mentors' salaries, SLMTA training and improvement project support. Building in-country capacity through local partners is a sustainable model for improving service quality in resource-constrained countries such as Ghana. Such models promote country ownership, capacity building and the use of local human resources for the expansion of SLMTA.

  2. Building local human resources to implement SLMTA with limited donor funding: The Ghana experience

    Directory of Open Access Journals (Sweden)

    Bernard Nkrumah

    2014-11-01

    Full Text Available Background: In 2009, Ghana adopted the Strengthening Laboratory Management Toward Accreditation (SLMTA programme in order to improve laboratory quality. The programme was implemented successfully with limited donor funding and local human resources. Objectives: To demonstrate how Ghana, which received very limited PEPFAR funding, was able to achieve marked quality improvement using local human resources. Method: Local partners led the SLMTA implementation and local mentors were embedded in each laboratory. An in-country training-of-trainers workshop was conducted in order to increase the pool of local SLMTA implementers. Three laboratory cohorts were enrolled in SLMTA in 2011, 2012 and 2013. Participants from each cohort attended in a series of three workshops interspersed with improvement projects and mentorship. Supplemental trainingon internal audit was provided. Baseline, exit and follow-up audits were conducted using the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA checklist. In November 2013, four laboratories underwent official SLIPTA audits by the African Society for Laboratory Medicine (ASLM. Results: The local SLMTA team successfully implemented three cohorts of SLMTA in 15 laboratories. Seven out of the nine laboratories that underwent follow-up audits have reached at least one star. Three out of the four laboratories that underwent official ASLM audits were awarded four stars. Patient satisfaction increased from 25% to 70% and sample rejection rates decreased from 32% to 10%. On average, $40 000 was spent per laboratory to cover mentors’salaries, SLMTA training and improvement project support. Conclusion: Building in-country capacity through local partners is a sustainable model for improving service quality in resource-constrained countries such as Ghana. Such modelspromote country ownership, capacity building and the use of local human resources for the expansion of SLMTA.

  3. Delivering on a gendered definition of health needs in local government budgeting: experiences and concepts.

    Science.gov (United States)

    Buyana, K

    2009-10-01

    Local governments are granted budgetary power in the Local Governments Act of the Republic of Uganda, which allows for local-level participation and flexibility in the allocation of financial grants channelled annually from central to local governments. The act prescribes a legal mandate to allocate public resources based on local priorities including the health needs of women compared with men. This study investigated the responsiveness of local government budgeting to the health needs of women as compared to men. A qualitative study was conducted in Mpigi district using a set of data collection methods including: a) three (3) focus group discussions with 8 female and 8 male respondents in each group; b) face-to-face interviews with a random sample of 120 households, 75% of which were male-headed and 25% female-headed ; c) key informant interviews with a sample of 10 administrative officers in Mpigi district ; and d) desk-review of the Mpigi district Budget Framework Paper. Health needs consist of the daily requirements, which, arise out of common disease infections and the socioeconomic constraints that affect the well-being of women and men. However, the primary concern of the district health sector is disease control measures, without emphasis on the differing socio-economic interests of women as compared to men. Local government budgeting, therefore, does not reflect the broad community-wide understanding of health needs. Local government budgeting should be informed by a two-fold framework for the gendered definition of health needs. The two-fold framework combines both disease-based health needs and socio-economic needs of women as compared to men.

  4. Radio-guided localization of clinically occult breast lesions (ROLL): a DGH experience

    International Nuclear Information System (INIS)

    Thind, C.R.; Desmond, S.; Harris, O.; Nadeem, R.; Chagla, L.S.; Audisio, R.A.

    2005-01-01

    AIM: Wire-guided localization (WGL) of clinically occult breast lesions is a well established technique. The aim of this study was to evaluate radio-guided localization (ROLL) within the breast screening service of a district general hospital. METHOD: The study group comprised 70 women who underwent ROLL under US and stereotaxis. This required an injection of Technetium-labelled colloidal albumen into the impalpable breast lesion. The women then proceeded to theatre, where localization was achieved with the use of a gamma probe. The lesion was identified by the presence of a high signal, caused by the injected isotope. The results of 70 consecutive cases in which a breast lesion was localized using ROLL were compared with the results of the latest 70 WGLs. RESULTS: All 140 lesions were successfully localized. However, the change in technique from WGL to ROLL offered significant benefits to patients. CONCLUSION: Our study demonstrated that ROLL is a practical and reliable localization technique. It can be implemented in hospital units without using valuable gamma camera time. The cost compares well with WGL. There is an improved cosmetic outcome for patients, and the very small quantity of radioactivity used is safe for both patients and staff

  5. The Influence of Soil Particle on Soil Condensation Water

    OpenAIRE

    Hou Xinwei; Chen Hao; Li Xiangquan; Cui Xiaomei; Liu Lingxia; Wang Zhenxing

    2013-01-01

    The experiment results showed that the indoor experiment formed from the volume of soil hygroscopic water increased gradually with decreasing size of soil particles. In the outdoor experiments, the results showed that the formed condensation water in medium sand was greater than it was in fine sand; the soil hot condensation water was mainly formed in the top layer of soil between 0-5 cm. We also found that covering the soil surface with stones can increase the volume of formed soil condensat...

  6. Study of condensate composition during field processing of gas of the Shatlyk field

    Energy Technology Data Exchange (ETDEWEB)

    Kuldzhayev, B.A.; Annamukhamedov, M.B.; Makarov, V.V.; Serbnenko, S.R.; Talalayev, Ye.I.

    1983-01-01

    Studies were made of the composition and properties of condensates from field separators of the East Shatlyk field. The expediency is shown of separate collection of the condensates into a separate container and used for local needs as the diesel fuel. The condensates from the UNTS separators are used as chemical raw material to produce the lowest olephins by pyrolysis of gas-oil fraction and normal paraffins from kerosene-gas-oil part to obtain the protein-vitamin concentrates.

  7. Preliminary experience of a three-dimensional, large-field-of-view PET scanner for the localization of partial epilepsy

    International Nuclear Information System (INIS)

    Binns, D.S.; O'Brien, T.J.; Murphy, M.; Cook, M.J.; Hicks, R.J.

    1999-01-01

    Full text: PET scanning is a useful ancillary technique in the localization of intractable partial epilepsy, but its widespread use has been limited by the high cost of traditional PET equipment and radioisotopes. The use of 3D-scanning mode with a large-field of-view PET scanner involves lower equipment costs and requires significantly lower doses of radioisotope. Our aim was to report our preliminary experience of the use of a 3-D, large-field-of-view scanner for FDG-PET studies in the localization of partial epilepsy. 31 patients (pts) with partial epilepsy were studied. The FDG-PET scans were reviewed blindly by a single reviewer without knowledge of seizure localization on structural imaging or ictal electroencephalographic (EEG) monitoring. The PET results were correlated with the localization by more traditional techniques and the results on surgery when available. A localized region of hypometabolism on FDG-PET scanning was reported in 26/31 (84%) patients (21 temporal, 5 extratemporal). This compared favourably with volumetric MRI on which 19/31 (61%) had a focal potentially epileptogenic abnormality, all of which were concordant with the PET localization. PET was concordant with ictal EEG onset in all 22 patients with localizing studies, including 5 pts with normal MRI. PET demonstrated localized hypometabolism in 4/5 pts with non-localizing ictal EEG and was concordant in both pts with abnormal MRI in this group. PET was considered normal in 4 pts, including 3 pts with normal MRI but localizing EEG and 1 pt without EEG or MRI abnormality. One pt with a localizing EEG and normal MRI was felt to have bitemporal hypometabolism. Five patients have subsequently had resective epilepsy surgery with 4 currently seizure-free and 1 significantly improved. Four patients are planned for surgery in the near future. In conclusion, FDG-PET using a 3-D, large-field-of view PET scanner provides sensitive and specific localization in partial epilepsy, and may provide a

  8. Condensation of sodium on a micromachined surface for AMTEC

    International Nuclear Information System (INIS)

    Crowley, C.J.; Izenson, M.G.

    1993-01-01

    A novel condenser component is being developed to enable Alkali Metal Thermal to Electric Conversion (AMTEC) technology to achieve two critical goals: (1) optimization of conversion efficiency and (2) microgravity fluid management. The first goal is achieved by minimizing parasitic radiation heat transfer losses for condensers with a large view factor to the high-temperature β double-prime-alumina surface. The condenser geometry includes a specially designed, micromachined surface where large capillary forces are used to manage the fluid distribution to accomplish the second goal. We present and discuss the results of separate effects experiments investigating the wetting and condensation behavior of sodium on this capillary surface. Test results show that the micromachined surface maintains a smooth, high reflective film of liquid sodium on the surface, which implies reduced parasitic losses and increased conversion efficiencies in AMTEC cells. Accomplishing this in an adverse gravity gradient demonstrates the potential for management of the fluid even under spacecraft acceleration conditions

  9. Condensate bright solitons under transverse confinement

    International Nuclear Information System (INIS)

    Salasnich, L.; Reatto, L.; Parola, A.

    2002-01-01

    We investigate the dynamics of Bose-Einstein condensate bright solitons made of alkali-metal atoms with negative scattering length and under harmonic confinement in the transverse direction. Contrary to the one-dimensional (1D) case, the 3D bright soliton exists only below a critical attractive interaction that depends on the extent of confinement. Such a behavior is also found in multisoliton condensates with box boundary conditions. We obtain numerical and analytical estimates of the critical strength beyond which the solitons do not exist. By using an effective 1D nonpolynomial nonlinear Schroedinger equation, which accurately takes into account the transverse dynamics of cigarlike condensates, we numerically simulate the dynamics of the 'soliton train' reported in a recent experiment [Nature (London) 417, 150 (2002)]. Then, analyzing the macroscopic quantum tunneling of the bright soliton on a Gaussian barrier, we find that its interference in the tunneling region is strongly suppressed with respect to nonsolitonic case; moreover, the tunneling through a barrier breaks the shape invariance of the matter wave. Finally, we show that the collapse of the soliton is induced by the scattering on the barrier or by the collision with another matter wave when the density reaches a critical value, for which we derive an accurate analytical formula

  10. Bose-Einstein condensation of paraxial light

    Science.gov (United States)

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-10-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have observed thermalization and subsequently Bose-Einstein condensation of the photon gas at room temperature. In this paper, we give a detailed description of the experiment, which is based on a dye-filled optical microcavity, acting as a white-wall box for photons. Thermalization is achieved in a photon number-conserving way by photon scattering off the dye molecules, and the cavity mirrors both provide an effective photon mass and a confining potential-key prerequisites for the Bose-Einstein condensation of photons. The experimental results are in good agreement with both a statistical and a simple rate equation model, describing the properties of the thermalized photon gas.

  11. Experimental study of air-cooled water condensation in slightly inclined circular tube using infrared temperature measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyungdae [Nuclear Engineering Department, Kyung Hee University, Yongin (Korea, Republic of); Kwon, Tae-Soon [Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Dong Eok, E-mail: dekim@knu.ac.kr [Department of Precision Mechanical Engineering, Kyungpook National University, Sangju (Korea, Republic of)

    2016-11-15

    Highlights: • Air-cooled condensation experiments in an inclined Pyrex glass tube were performed. • High-resolution wall temperature data and flow regime formations could be obtained. • The local heat flux was strongly dependent on the air-side heat transfer. • A CFD analysis was conducted for calculating the local heat flux distribution. - Abstract: This study presents the results of an investigation of the air-cooled water condensation heat transfer characteristics inside a slightly inclined circular tube made of transparent Pyrex glass. The high-resolution wall temperature data and stratified film formations could be obtained with the assistance of an infrared (IR) thermometry technique and side-view visualization using a CCD camera. In all experimental cases, the condensation flow patterns were in the fully-stratified flow region. In addition, the experimentally measured void fraction corresponded well with the logarithmic mean void fraction model. The local temperature differences in the cooling air flow across the condenser tube and high-resolution temperature profiles on the tube’s outer wall were obtained in the experimental measurements. Under the experimental conditions of this study, the local heat flux distributions in the longitudinal direction of the test tube were strongly dependent on the cooling air velocity. And, with the help of IR thermometry, the tube outer wall temperature data at 45 local points could be measured. From the data, the asymmetry distribution of the local wall temperatures and the accurate location of the transition from two-phase mixture to single phase liquid inside the tube could be obtained. Also, the analysis of the thermal resistances by condensation, wall conduction and air convection showed that the air convective heat transfer behavior can play a dominant role to the local heat transfer characteristics. Finally, in order to obtain the local heat flux distribution along the tube’s outer wall, a two

  12. Numerical Study of Condensation Heat Exchanger Design in a Subcooled Pool: Correlation Investigation

    International Nuclear Information System (INIS)

    Lee, Hee Joon; Ju, Yun Jae; Kang, Han Ok; Lee, Tae Ho; Park, Cheon Tae

    2012-01-01

    Generally the condensation heat exchanger has higher heat transfer coefficient compared to the single phase heat exchanger, so has been widely applied to the cooling systems of energy plant. Recently vertical or horizontal type condensation heat exchangers are being studied for the application to secondary passive cooling system of nuclear plants. Lee and Lee investigated the existing condensation correlation to the experiment for heat exchanger in saturated pool. They concluded Traviss' correlation showed most satisfactory results for the heat transfer coefficient and mass flow rate in a saturated water pool. In this study, a thermal sizing program of vertical condensation heat exchanger to design, TSCON(Thermal Sizing of CONdenser) was validated with the existing experimental data of condensation heat exchanger in a subcooled pool for pure steam condensation

  13. Evaporation and condensation heat transfer with a noncondensable gas present

    International Nuclear Information System (INIS)

    Murase, M.; Kataoka, Y.; Fujii, T.

    1993-01-01

    To evaluate the system pressure of an external water wall type containment vessel, which is one of the passive systems for containment cooling, the evaporation and condensation behavior under a noncondensable gas presence has been experimentally examined. In the system, steam evaporated from the suppression pool surface into the wetwell, filled with noncondensable gas, and condensed on the containment vessel wall. The system pressure was the sum of the noncondensable gas pressure and saturated steam pressure in the wetwell. The wetwell temperature was, however, lower than the suppression pool temperature and depended on the thermal resistance on the suppression pool surface. The evaporation and condensation heat transfer coefficients in the presence of air as noncondensable gas were measured and expressed by functions of steam/air mass ratio. The evaporation heat transfer coefficients were one order higher than the condensation heat transfer coefficients because the local noncondensable gas pressure was much lower on the evaporating pool surface than on the condensing liquid surface. Using logal properties of the heat transfer surfaces, there was a similar trend between evaporation and condensation even with a noncondensable gas present. (orig.)

  14. Experimental and theoretical study of reflux condensation

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Knut

    1997-12-31

    This thesis studies the separation of gas mixtures in a reflux condenser. also called a dephlegmator. Reflux condensation is separation of a gas mixture, in reflux flow with condensing liquid, under continuous heat removal. A numerical model of a dephlegmator for binary mixtures was developed. The model may readily be extended to multi-component mixtures, as the solution method is based on a matrix solver. Separation of a binary mixture in a reflux condenser test rig is demonstrated. The test facility contains a single-tube test section that was designed and built as part of the project. Test mixtures of propane and n-butane were used, and a total of 15 experiments are reported. Limited degree of separation was achieved due to limited heat transfer area and narrow boiling point range of the test mixture. The numerical model reproduces the experimental data within reasonable accuracy. Deviation between calculated and measured properties is less than 6% of the measured temperature and less than 5% of the measured flow rate. The model is based on mechanistic models of physical processes and is not calibrated or tuned to fit the experimental data. The numerical model is applied to a number of separation processes. These case studies show that the required heat transfer area increases rapidly with increments in top product composition (light component). Flooding limits the amount of reflux liquid. The dephlegmator is suitable for separation of feed mixtures that are rich in light components. The gliding temperature in the dephlegmation process enables utilization of top product as refrigerant, with subsequent energy saving as a result. 61 refs., 50 figs., 34 tabs.

  15. Bose condensation in 4He and neutron scattering

    International Nuclear Information System (INIS)

    Silver, R.N.

    1997-01-01

    The discovery of superfluidity in liquid 4 He below T λ = 2.17 K, and its phenomenological characterization since then, has been one of the great success stories of condensed matter physics. The relation of superfluidity to the behavior of atoms was conjectured by F. London in 1938. Superfluidity is a manifestation of the Bose condensation of helium atoms, the extensive occupation of the zero momentum state. Ever since 4 He has been the paradigm in the search for Bose condensates in other systems. At the Pune meeting scientists have heard exciting new evidence for Bose condensates of laser cooled alkali atoms in magnetic traps, of excitons in Cu 2 O, and possibly pre-formed Cooper pairs of electrons in the high T c perovskite superconductors. There remains the holy-grail of forming a Bose condensate in spin-polarized hydrogen. In the current excitement for new types of Bose condensates, and new phenomena such as atom lasers, it may be useful to recall the older story of the experimental verification of a relation between superfluidity and Bose condensation in 4 He. This topic has been investigated over many years by neutron scattering experiments and quantum many-body theory. The authors goal is to illustrate the difficulties of establishing the existence of a Bose condensate in a strongly interacting system, even though its macroscopic effects are manifest. The author assumes readers have access to a review by Silver and Sokol which emphasizes the neutron scattering theory through 1990 and a review by Snow and Sokol of the deep inelastic neutron scattering (DINS) experiments through 1995

  16. Titanium condenser tubes--problems and their solutions for wider application to large surface condensers

    Energy Technology Data Exchange (ETDEWEB)

    Sato, S; Sugiyama, Y; Nagata, K; Namba, K; Shimono, M

    1978-01-01

    To meet the demand for high reliability condensers for thermal and nuclear power plants, especially for PWR plants, the condensers installed entirely with titanium tubes have been investigated and used. Some difficulties from conventional copper alloy tubes exist. Further investigations are necessary on three items: (1) tube vibration; (2) joining tubes to tube plate; (3) fouling (bio-fouling) control. Literature survey on the tube vibration suggests that the probability of tube vibration due to decreased stiffness of titanium tubes in comparison with conventional copper alloy tubes can be decreased by designing the proper span length between supports. Experiments on seal welding of tubes to a tube plate have successfully proved that pulsed TIG arc welding is applicable to get reliable and strong joints, even on site, by suitable countermeasures. Experiments on the fouling (bio-fouling) of titanium tubes in marine application reveal that the increased fouling of titanium tubes could be controlled by proper application of sponge ball cleaning.

  17. A search for disoriented chiral condensate at Fermilab

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1996-10-01

    A small test/experiment at the Fermilab Collider which measures charged particle and photon multiplicities in the forward direction, η ∼ 4.1, has been carried out, with the primary goal being the search for disoriented chiral condensate (DCC). The author describes the experiment and analysis methods, together with preliminary results

  18. Experimental and theoretical investigations on condensation heat transfer at very low pressure to improve power plant efficiency

    International Nuclear Information System (INIS)

    Berrichon, J.D.; Louahlia-Gualous, H.; Bandelier, Ph.; Bariteau, N.

    2014-01-01

    Highlights: • Theoretical model for condensation heat transfer at very low pressure is developed using only one iterative loop. • Experimental results on steam and air steam condensation heat transfer at very low pressure are presented. • The developed model gives the good predictions for local condensation heat transfer at low pressure. • A maximal deterioration of 50% in condensation heat transfer is obtained at low pressure for air fraction of 4%. • A new correlation including effect of a wavy film surface for steam condensation at low pressure is suggested. - Abstract: This paper presents experimental investigation on the influence of very low pressure on local and average condensation heat transfer in a vertical tube. Furthermore, this paper develops an analytical study for film condensation heat transfer coefficient in the presence of non-condensable gas inside a vertical tube. The condensate film thickness is calculated for each location in a tube using mass and heat transfer analogy. The effects of interfacial shear stress and waves on condensate film surface are included in the model. The comparative studies show that the present model well predicts the experimental data of Khun et al. [1]for local condensation of steam air mixture at high pressure. Different correlations defined for condensation heat transfer are evaluated. It is found that the correlations of Cavallini and Zecchin [2] and Shah [3] are the closest to the calculated steam condensation local heat transfer coefficient. The model gives a satisfactory accuracy with the experimental results for condensation heat transfer at very low pressure. The mean deviation between the predictions of the theoretical model with the measurements for pure saturated vapor is 12%. Experimental data show that the increase of air fraction to 4% deteriorates condensation heat transfer at low pressure up to 50%

  19. Dual approaches for defects condensation

    Energy Technology Data Exchange (ETDEWEB)

    Rougemont, Romulo; Grigorio, Leonardo de Souza; Wotzasek, Clovis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Guimaraes, Marcelo Santos [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

    2009-07-01

    Full text. Due to the fact that the QCD running coupling constant becomes larger as we go into the low energy (or large distance) limit of the theory, a perturbative treatment of its infrared (IR) region is impossible. In particular, a formal mathematical demonstration of color confinement and a complete physical understanding of the exact mechanism that confines quarks and gluons are two missing points in our current knowledge of the IR-QCD. It was known that due to the Meissner effect of expulsion of magnetic fields in a electric condensate that usual superconductors should confine magnetic monopoles. That point led to the conjecture that the QCD vacuum could be a condensate of chromomagnetic monopoles, a dual superconductor (DSC). Such a chromomagnetic condensate should be responsible for the dual Meissner effect which is expected to lead to the confinement of color charges immersed in this medium. In dual superconductor models of color confinement, magnetic monopoles appear as topological defects in points of the space where the abelian projection becomes singular. Also, condensation of other kinds of defects such as vortices in superfluids and line-like defects in solids are responsible for a great variety of phase transitions, which once more proves the relevance of the subject. In the present work we review two methods that allow us to approach the condensation of defects: the Kleinert Mechanism (KM) and the Julia-Toulouse Mechanism (JTM). We show that in the limit where the vortex gauge field goes to zero, which we identify as the signature of the condensation of defects in the dual picture, these are two equivalent dual prescriptions for obtaining an effective theory for a phase where defects are condensed, starting from the fundamental theory defined in the normal phase where defects are diluted. (author)

  20. The Rise and Fall of the Concept of The Experience Economy in the Local Economic Development of Denmark

    DEFF Research Database (Denmark)

    Freire-Gibb, L. Carlos

    2011-01-01

    , nor to tourist attractions, which are also linked to TEE. However, it criticizes the implementation of an unorthodox idea to Local Economic Development, even though it may have useful principles to other disciplines. This article reflects the line of recent research which has questioned its......This article discusses the evolution of the concept of “The Experience Economy“ (TEE) in the Danish local economic policy. The term is rarely known worldwide; however, it has become quite popular among the Danes and other Scandinavians. Its origin comes from the American business-marketing field...... in the late 1990s, while in Denmark, it evolved as a multifaceted idea with notable effects for economic development at the local level. The concept is related to the cultural or creative economy, but in the Danish case, it became more diffuse. This article does not intend to be a critique of these two lines...

  1. Quantum mechanics versus local realism and a recent EPR experiment on K/sup 0/K/sup 0/ pairs

    CERN Document Server

    Foadi, R

    1999-01-01

    The interest of the Orsay Einstein-Podolsky-Rosen experiments of the eighties was limited by a loophole due to the photomultipliers' low detection efficiency. This limitation can be overcome in the case of neutral kaon pairs for which the detection efficiency is high. We show that for such pairs produced in the state J/sup PC/=1/sup --/ the prediction of local realism differ from those of standard quantum theory by 30561400r more. A natural extension of a recent experiment on antiproton annihilations at rest into kaon pairs (CPLEAR collaboration, A. Apostolakis et al., 1998) could lead to a decisive step forward in this matter. (19 refs).

  2. Observation of a High Performance Operating Regime with Small Edge-Localized Modes in the National Spherical Torus Experiment

    International Nuclear Information System (INIS)

    Maingi, R.; Tritz, K.; Fredrickson, E.D.; Menard, J.E.; Sabbagh, S.A.; Stutman, D.; Bell, M.G.; Bell, R.E.; Bush, C.E.; Gates, D.A.; Johnson, D.W.; Kaita, R.; Kaye, S.M.; Kugel, H.W.; LeBlanc, B.P.; Mueller, D.; Raman, R.; Roquemore, A.L.; Soukhanovskii, V.A.

    2004-01-01

    We report observation of a high performance scenario in the National Spherical Torus Experiment with very small edge-localized modes (ELMs). These ELMs have no measurable impact on stored energy and are consistent with high bootstrap current operation with line average density approaching Greenwald scaling. The ELM perturbation is observed to typically originate near the lower divertor region, as opposed to the outer midplane for ELMs described in the literature. If extrapolable, this scenario would provide an attractive operating regime for next step fusion experiments

  3. An Integrated Online Library System as a Node in a Local Area Network: The Mitre Experience.

    Science.gov (United States)

    Kidwell, Mary Coyle

    1987-01-01

    Discusses the Mitre Corporation's implementation of OCLC's LS/2000 integrated library system using a local area network (LAN). LAN issues--requirements, equipment, reliability, growth, security, and traffic--are covered in general and as they relate to Mitre. Installation of the LAN/system interface and benefits and drawbacks of using a LAN for…

  4. I saw the sign: the new federal menu-labeling law and lessons from local experience.

    Science.gov (United States)

    Banker, Michelle I

    2010-01-01

    Following the lead of several state and local governments, Congress recently imposed menu-labeling requirements on chain restaurants as part of the federal health care reform bill signed into law in March 2010. Section 4205 of the Patient Protection and Affordable Care Act requires restaurant chains with 20 or more locations nationwide to display calorie information for standard menu items on menus, menu boards, and drive-thru displays. This paper examines the new federal law in light of existing state and local regulations and considers the arguments for and against mandatory calorie labeling at restaurants as a federal tool for preventing obesity. Specifically, this paper examines the provisions of the new federal law, highlights how it differs from the municipal and state menu-labeling laws already in effect, reviews early studies of the effectiveness of these state and local laws, and considers the propriety of requiring restaurants to disclose calorie information on menus by discussing arguments for and against menu labeling generally and calorie labeling in particular. This paper finds that based on initial studies of state and local menu-labeling regulations, the efficacy of compulsory menu labeling as a tool to combat obesity remains uncertain. Finally, this paper raises practical considerations associated with the new federal law, including implementation issues, potential collateral effects of the law, a survey of legal challenges that may arise, and a discussion of the Food and Drug Administration's competence to enforce a menu-labeling requirement against restaurants.

  5. Experiences with USAR mobile interfaces : The need for persistent geo-localized information

    NARCIS (Netherlands)

    Larochelle, B.; Kruijff, G.J.M.; Smets, N.J.J.M.; Diggelen, J. van

    2013-01-01

    Urban search and rescue (USAR) missions are unique and unpredictable. Communication and coordination is difficult, with high-level actors (e.g. mission commander) lacking local terrain knowledge while low-level actors (e.g. robot operators, in-field rescuers) lack global situation awareness (SA).

  6. Mycorrhizal Symbiosis and Local Adaptation in Aster amellus: A Field Transplant Experiment

    Czech Academy of Sciences Publication Activity Database

    Pánková, Hana; Raabová, J.; Münzbergová, Zuzana

    2014-01-01

    Roč. 9, č. 4 (2014), s. 1-7, e93967 E-ISSN 1932-6203 R&D Projects: GA ČR GAP504/10/1486 Institutional support: RVO:67985939 Keywords : mycorrhizal symbiosis * local adaptation * Aster amellus Subject RIV: EF - Botanics Impact factor: 3.234, year: 2014

  7. Condensation: the new deal; Condensation: la nouvelle donne

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-01

    The principle of condensation boilers is based on the recovery of the latent heat of the steam generated by the combustion of natural gas. This technology was introduced in France at the end of the 80's but failed in its promise because of the complexity of the equipments available at that time. Today, constructors' offer is more mature and reliable and the context has changed. This technology can conciliate three goals: a mastery of energy consumptions, the comfort of the user and the respect of environment. This meeting organized by the research center of Gaz de France (Cegibat), was a good opportunity to makes a status of the market of individual condensation systems in France and in Europe, to present the situation of this technology today and the 10 golden rules for the fitting and maintenance of individual condensation boilers, and to present some technical references, examples and results of today's offer. (J.S.)

  8. Research progress of control of condensate depression for condenser

    Science.gov (United States)

    Liu, Ying; Liang, Run; Li, Fengyu

    2017-08-01

    It is introduced that significance and structure of the condensate depression control system. In accordance with controller devised procedure, we analyze and elaborate how to construct the lumped parameter and dynamic mathematical model which possesses distinct physics significance. Neural network model being called black-box model is also introduced. We analyze and contrast the control technique of condensate depression as conventional PI control, fuzzy PI control and fuzzy control. It is indicated that if the controller of condensate depression were devised inappropriate, while the steam discharged of turbine varying by a large margin, would result in the rotation rate of cooling water circulating pump accelerating at a great lick even to trigger the galloping danger which is less impressive for the units operating safely.

  9. Discrete breathers in Bose–Einstein condensates

    International Nuclear Information System (INIS)

    Franzosi, Roberto; Politi, Antonio; Livi, Roberto; Oppo, Gian-Luca

    2011-01-01

    Discrete breathers, originally introduced in the context of biopolymers and coupled nonlinear oscillators, are also localized modes of excitation of Bose–Einstein condensates (BEC) in periodic potentials such as those generated by counter-propagating laser beams in an optical lattice. Static and dynamical properties of breather states are analysed in the discrete nonlinear Schrödinger equation that is derived in the limit of deep potential wells, tight-binding and the superfluid regime of the condensate. Static and mobile breathers can be formed by progressive re-shaping of initial Gaussian wave-packets or by transporting atomic density towards dissipative boundaries of the lattice. Static breathers generated via boundary dissipations are determined via a transfer-matrix approach and discussed in the two analytic limits of highly localized and very broad profiles. Mobile breathers that move across the lattice are well approximated by modified analytical expressions derived from integrable models with two independent parameters: the core-phase gradient and the peak amplitude. Finally, possible experimental realizations of discrete breathers in BEC in optical lattices are discussed in the presence of residual harmonic trapping and in interferometry configurations suitable to investigate discrete breathers' interactions. (invited article)

  10. High resolution modelling of aerosol dispersion regimes during the CAPITOUL field experiment: from regional to local scale interactions

    Directory of Open Access Journals (Sweden)

    B. Aouizerats

    2011-08-01

    Full Text Available High resolution simulation of complex aerosol particle evolution and gaseous chemistry over an atmospheric urban area is of great interest for understanding air quality and processes. In this context, the CAPITOUL (Canopy and Aerosol Particle Interactions in the Toulouse Urban Layer field experiment aims at a better understanding of the interactions between the urban dynamics and the aerosol plumes. During a two-day Intensive Observational Period, a numerical model experiment was set up to reproduce the spatial distribution of specific particle pollutants, from the regional scales and the interactions between different cities, to the local scales with specific turbulent structures. Observations show that local dynamics depends on the day-regime, and may lead to different mesoscale dynamical structures. This study focuses on reproducing these fine scale dynamical structures, and investigate the impact on the aerosol plume dispersion. The 500-m resolution simulation manages to reproduce convective rolls at local scale, which concentrate most of the aerosol particles and can locally affect the pollutant dispersion and air quality.

  11. Condensed Matter Theories: Volume 25

    Science.gov (United States)

    Ludeña, Eduardo V.; Bishop, Raymond F.; Iza, Peter

    2011-03-01

    pt. A. Fermi and Bose fluids, exotic systems. Reemergence of the collective mode in [symbol]He and electron layers / H. M. Bohm ... [et al.]. Dissecting and testing collective and topological scenarios for the quantum critical point / J. W. Clark, V. A. Khodel and M. V. Zverev. Helium on nanopatterned surfaces at finite temperature / E. S. Hernandez ... [et al.]. Towards DFT calculations of metal clusters in quantum fluid matrices / S. A. Chin ... [et al.]. Acoustic band gap formation in metamaterials / D. P. Elford ... [et al.]. Dissipative processes in low density strongly interacting 2D electron systems / D. Neilson. Dynamical spatially resolved response function of finite 1-D nano plasmas / T. Raitza, H. Reinholz and G. Ropke. Renormalized bosons and fermions / K. A. Gernoth and M. L. Ristig. Light clusters in nuclear matter / G. Ropke -- pt. B. Quantum magnets, quantum dynamics and phase transitions. Magnetic ordering of antiferromagnets on a spatially anisotropic triangular lattice / R. F. Bishop ... [et al.]. Thermodynamic detection of quantum phase transitions / M. K. G. Kruse ... [et al.]. The SU(2) semi quantum systems dynamics and thermodynamics / C. M. Sarris and A. N. Proto -- pt. C. Physics of nanosystems and nanotechnology. Quasi-one dimensional fluids that exhibit higher dimensional behavior / S. M. Gatica ... [et al.]. Spectral properties of molecular oligomers. A non-Markovian quantum state diffusion approach / J. Roden, W. T. Strunz and A. Eisfeld. Quantum properties in transport through nanoscopic rings: Charge-spin separation and interference effects / K. Hallberg, J. Rincon and S. Ramasesha. Cooperative localization-delocalization in the high T[symbol] cuprates / J. Ranninger. Thermodynamically stable vortex states in superconducting nanowires / W. M. Wu, M. B. Sobnack and F. V. Kusmartsev.pt. D. Quantum information. Quantum information in optical lattices / A. M. Guzman and M. A. Duenas E. -- pt. E. Theory and applications of molecular

  12. A Study on Condensation Heat Transfer at the Exterior Surface of S.A.M. Coated Titanium Tube Using in Steam Condensers

    Energy Technology Data Exchange (ETDEWEB)

    Im, Sung-Gu; Lee, Sang-Hyup; Ji, Dae-Yun; Park, Hyun-Gyu; Lee, Kwon-Yeong [Handong Global University, Pohang (Korea, Republic of)

    2016-10-15

    Condensation occurs when the temperature of a steam is reduced below its saturation temperature. There exist two forms of condensation on cooling surface: dropwise, and film condensations. Usually, dropwise condensation has a better heat transfer performance than film condensation, but it has limit of short period. Ma et al. executed heat transfer experiment in dropwise condensation with non-condensable gas, and studied how the amount of air and pressure difference affect condensation heat transfer coefficient. The more non-condensable gas exist, the condensation heat transfer coefficient is decreased. As a result, surface modified brass tube and stainless tube showed higher condensation heat transfer coefficient as much as 1.3 and 1.4 times comparing with their bare tubes in 70 kPa vacuum condition respectively. Most of power plants use sea water as coolant, so the surface of metal tubes could be corroded by the coolant. We had researched an experimental study related to condensation heat transfer on surface modified titanium tube. Our experimental facility was designed to show how two kinds of tube's heat transfer performances are different in a same condition. We changed the range of saturation pressure and coolant flow rate to observe tube's performance change. When saturation pressure and coolant flow rate increase, overall heat transfer coefficients were increased. When residue of non-condensable gases was decreased, the overall heat transfer coefficients were increased. S.A.M. coated tube's overall heat transfer coefficients were lower than those of bare tube, because the droplets didn't have a tendency of frequently falling down.

  13. Hidden Scale Invariance in Condensed Matter

    DEFF Research Database (Denmark)

    Dyre, J. C.

    2014-01-01

    . This means that the phase diagram becomes effectively one-dimensional with regard to several physical properties. Liquids and solids with isomorphs include most or all van der Waals bonded systems and metals, as well as weakly ionic or dipolar systems. On the other hand, systems with directional bonding...... (hydrogen bonds or covalent bonds) or strong Coulomb forces generally do not exhibit hidden scale invariance. The article reviews the theory behind this picture of condensed matter and the evidence for it coming from computer simulations and experiments...

  14. Pain Experience and Behavior Management in Pediatric Dentistry: A Comparison between Traditional Local Anesthesia and the Wand Computerized Delivery System.

    Science.gov (United States)

    Garret-Bernardin, Annelyse; Cantile, Tiziana; D'Antò, Vincenzo; Galanakis, Alexandros; Fauxpoint, Gabriel; Ferrazzano, Gianmaria Fabrizio; De Rosa, Sara; Vallogini, Giulia; Romeo, Umberto; Galeotti, Angela

    2017-01-01

    Aim. To evaluate the pain experience and behavior during dental injection, using the Wand computerized delivery system versus conventional local anesthesia in children and adolescents. Methods. An observational crossover split mouth study was performed on 67 patients (aged 7 to 15 years), requiring local anesthesia for dental treatments in both sides of the dental arch. Patients received both types of injections in two separate appointments, one with the use of a Computer Delivery System (the Wand STA system) and one with the traditional syringe. The following data were recorded: pain rating; changes in heart rate; level of collaboration; patient satisfaction. The data were analyzed using ANOVA for quantitative outcomes and nonparametric analysis (Kruskal-Wallis) for qualitative parameters. Results. The use of the Wand system determined significantly lower pain ratings and lower increase of heart rate than the traditional syringe. During injection, the number of patients showing a relaxed behavior was higher with the Wand than with the traditional local anesthesia. The patient level of satisfaction was higher with the Wand compared to the conventional local anesthesia. Conclusions. The Wand system may provide a less painful injection when compared to the conventional local anesthesia and it seemed to be better tolerated with respect to a traditional syringe.

  15. Pain Experience and Behavior Management in Pediatric Dentistry: A Comparison between Traditional Local Anesthesia and the Wand Computerized Delivery System

    Directory of Open Access Journals (Sweden)

    Annelyse Garret-Bernardin

    2017-01-01

    Full Text Available Aim. To evaluate the pain experience and behavior during dental injection, using the Wand computerized delivery system versus conventional local anesthesia in children and adolescents. Methods. An observational crossover split mouth study was performed on 67 patients (aged 7 to 15 years, requiring local anesthesia for dental treatments in both sides of the dental arch. Patients received both types of injections in two separate appointments, one with the use of a Computer Delivery System (the Wand STA system and one with the traditional syringe. The following data were recorded: pain rating; changes in heart rate; level of collaboration; patient satisfaction. The data were analyzed using ANOVA for quantitative outcomes and nonparametric analysis (Kruskal–Wallis for qualitative parameters. Results. The use of the Wand system determined significantly lower pain ratings and lower increase of heart rate than the traditional syringe. During injection, the number of patients showing a relaxed behavior was higher with the Wand than with the traditional local anesthesia. The patient level of satisfaction was higher with the Wand compared to the conventional local anesthesia. Conclusions. The Wand system may provide a less painful injection when compared to the conventional local anesthesia and it seemed to be better tolerated with respect to a traditional syringe.

  16. Experience from three years of local capacity development for tsunami early warning in Indonesia: challenges, lessons and the way ahead

    Science.gov (United States)

    Spahn, H.; Hoppe, M.; Vidiarina, H. D.; Usdianto, B.

    2010-07-01

    Five years after the 2004 tsunami, a lot has been achieved to make communities in Indonesia better prepared for tsunamis. This achievement is primarily linked to the development of the Indonesian Tsunami Early Warning System (InaTEWS). However, many challenges remain. This paper describes the experience with local capacity development for tsunami early warning (TEW) in Indonesia, based on the activities of a pilot project. TEW in Indonesia is still new to disaster management institutions and the public, as is the paradigm of Disaster Risk Reduction (DRR). The technology components of InaTEWS will soon be fully operational. The major challenge for the system is the establishment of clear institutional arrangements and capacities at national and local levels that support the development of public and institutional response capability at the local level. Due to a lack of information and national guidance, most local actors have a limited understanding of InaTEWS and DRR, and often show little political will and priority to engage in TEW. The often-limited capacity of local governments is contrasted by strong engagement of civil society organisations that opt for early warning based on natural warning signs rather than technology-based early warning. Bringing together the various actors, developing capacities in a multi-stakeholder cooperation for an effective warning system are key challenges for the end-to-end approach of InaTEWS. The development of local response capability needs to receive the same commitment as the development of the system's technology components. Public understanding of and trust in the system comes with knowledge and awareness on the part of the end users of the system and convincing performance on the part of the public service provider. Both sides need to be strengthened. This requires the integration of TEW into DRR, clear institutional arrangements, national guidance and intensive support for capacity development at local levels as well as

  17. Social media, FOAMed in medical education and knowledge sharing: Local experiences with international perspective

    Directory of Open Access Journals (Sweden)

    Arif Alper Cevik

    2016-09-01

    Full Text Available Social media, through the Internet and other web-based technologies, have become a means of communication and knowledge-sharing. In this article, we provide details about the social media traffic of various scientific activities, the organizations of which we have played an active role in. We also provide information in our native language through our FOAMed website, which has been published for about 30 months, with us acting as editors. We are comparing these local and limited ventures with examples from the world and aim to remind that social media sources play a very important role in sharing knowledge in medical training and encouraging local initiatives, like ours, with limited resources. Keywords: Medical education, Social media, FOAMed, Knowledge sharing

  18. Preliminary experience with external hemipelvectomy for locally advanced and recurrent pelvic carcinoma

    DEFF Research Database (Denmark)

    Nielsen, Mette Bak; Rasmussen, Peter Chr.; Keller, Johnny Østergaard

    2012-01-01

    was found. With agreement by the multidisciplinary team, surgery was performed by a colorectal surgeon and an orthopaedic sarcoma surgeon and, if needed, by an urologist and vascular surgeon. Patients were reconstructed with either a femoral or a gluteal musculocutaneous flap. Results Of the eight women...... [median age 54.5 (40– 68) years], two had primary carcinoma and six local recurrence of a previously treated carcinoma. R0 was possible in six patients and R1 resection in two. The median duration of hospital stay was 29.5 (17– 102) days. The median follow up was 8.3 (4.7– 52.8) months. Three patients...... for a highly selected group of patients with locally advanced carcinoma or recurrence involving the lumbosacral neural plexus....

  19. Experience, limits of and prospects for quick local analysis of harmful organic substances

    International Nuclear Information System (INIS)

    Matz, G.

    1993-01-01

    In the area of cleaning up old loads, both in exploration and also for concrete measures such as removing layers or cleaning the soil, the three-dimensionality and non-homogeneousness of the distribution of the harmful substances underground leads to very large numbers of samples, which must be analysed to describe the problem. If the analyses can be carried out directly locally and quickly, then based on the analysis results, the effect on the sample grid and on the course of the work can be estimated. The exploration and cleaning up cases carried out with the quick GC-MS analysis have shown that local analysis, firstly, represents a reasonably priced alternative to conventional laboratory analysis and, secondly, has advantages which very greatly accelerate work on old loads. (orig.) [de

  20. Range-based underwater vehicle localization in the presence of unknown ocean currents: Theory and experiments

    Digital Repository Service at National Institute of Oceanography (India)

    Bayat, M.; Crasta, N.; Aguiar, A.P.; Pascoal, A.M.

    under- water, due to the high attenuation of electromagnetic signals. The above problem can in principle be overcome by resorting to high-performance inertial navigation systems (INS). However, the cost of such systems may be prohibitive. Moreover, even... that include ultra short baseline (USBL), long baseline (LBL), and GPS intelligent buoy (GIB) systems. In practice, acoustic localization systems are often affected by the presence of outliers, latency, and multipath effects. In spite of this, however, acoustic...

  1. Breast Conserving Surgery and Sentinel Lymph Node Biopsy in Locally Advanced Breast Cancer: Single Center Experience

    Directory of Open Access Journals (Sweden)

    Atakan Sezer

    2011-06-01

    Full Text Available Objective: Patients with locally advanced breast cancer may undergo breast conserving surgery after neoadjuvant chemotherapy. The aim of the study is to evaluate the results of locally advanced breast cancer patients who underwent breast conserving surgery, axillary dissection and sentinel lymph node biopsy in a single center. Material and Methods: 12 patients with locally advanced breast cancer stage IIIA/IIIB were included in the study between 2002-2009. The patients were given anthracycline-based regimen before surgery. Patients underwent breast conserving surgery, axillary dissection, and sentinel lymph node biopsy followed by radiotherapy. Results: There were five patients in stage IIIA, six in stage IIIB, and one in stage IIIC. Patients had received 3-6 regimen of FAC/FEC. Eight had partial and four had complete response. Five positive axilla were detected. The median value of the lymph nodes was 12 (n:8-19. Five patients underwent sentinel lymph node biopsy. The biopsy has failed in one patient and the median value of dissected sentinel node was 3.5 (n:3-4. Locoregional recurrence was not observed in any patients. The mean follow-up of the patients was 29.8 months and median time was 16 (n:2-80 months.Of the 12 patients 10 are alive and 2 were deceased. Conclusion: In selected locally advanced patients, breast conserving surgery and sentinel lymph node biopsy may be applied by a multidisciplinary approach, and excellent success may be achieved in those patients as in early breast cancer patients.

  2. Localization of short-range acoustic and seismic wideband sources: Algorithms and experiments

    Science.gov (United States)

    Stafsudd, J. Z.; Asgari, S.; Hudson, R.; Yao, K.; Taciroglu, E.

    2008-04-01

    We consider the determination of the location (source localization) of a disturbance source which emits acoustic and/or seismic signals. We devise an enhanced approximate maximum-likelihood (AML) algorithm to process data collected at acoustic sensors (microphones) belonging to an array of, non-collocated but otherwise identical, sensors. The approximate maximum-likelihood algorithm exploits the time-delay-of-arrival of acoustic signals at different sensors, and yields the source location. For processing the seismic signals, we investigate two distinct algorithms, both of which process data collected at a single measurement station comprising a triaxial accelerometer, to determine direction-of-arrival. The direction-of-arrivals determined at each sensor station are then combined using a weighted least-squares approach for source localization. The first of the direction-of-arrival estimation algorithms is based on the spectral decomposition of the covariance matrix, while the second is based on surface wave analysis. Both of the seismic source localization algorithms have their roots in seismology; and covariance matrix analysis had been successfully employed in applications where the source and the sensors (array) are typically separated by planetary distances (i.e., hundreds to thousands of kilometers). Here, we focus on very-short distances (e.g., less than one hundred meters) instead, with an outlook to applications in multi-modal surveillance, including target detection, tracking, and zone intrusion. We demonstrate the utility of the aforementioned algorithms through a series of open-field tests wherein we successfully localize wideband acoustic and/or seismic sources. We also investigate a basic strategy for fusion of results yielded by acoustic and seismic arrays.

  3. Simplified Surgical Placement of Tenckhoff Catheter under Local Anesthesia: The Dammam Central Hospital Experience

    Directory of Open Access Journals (Sweden)

    Youmbissi T

    2001-01-01

    Full Text Available Many methods are used for the placement of Tenckhoff catheters. Eighteen consecutive Tenckhoff catheters were placed under local anesthesia through a mini laparotomy with a reduced operating team. There were only three total catheter failures. Complications were infrequent and operating time was less than one hour on average. This simple procedure should be a part of the training program of all junior surgeons and nephrologists.

  4. Numerical model of sprayed air cooled condenser coupled to refrigerating system

    International Nuclear Information System (INIS)

    Youbi-Idrissi, M.; Macchi-Tejeda, H.; Fournaison, L.; Guilpart, J.

    2007-01-01

    Because of technological, economic and environmental constraints, many refrigeration and air conditioning units are equipped with a simple air cooled condenser. Spraying the condenser seems to be an original solution to improve the energetic performances of such systems. To characterise this energetic benefit, a semi-local mathematical model was developed and applied to a refrigerating machine with and without spraying its air cooled condenser. It is found that, compared to a dry air cooled condenser, both the calorific capacity and machine COP increase by 13% and 55%, respectively. Furthermore, the model shows that a spray flow rate threshold occurs. It should not be exceeded to assure an effective and rational spray use

  5. Environmental monitoring and independent analysis: the experience of the local information commission in Cadarache

    International Nuclear Information System (INIS)

    Foucher, M.

    2010-01-01

    The 2006 Act on 'Open Access to Information and Nuclear Safety' provides free access to nuclear installations data and submits nuclear facilities to an independent administrative authority, the ASN (French Nuclear Safety Authority). A local information committee (CLI - Commission locale d'informations) has been set up for each nuclear facility. It includes all the parties involved and may commission expert studies and environmental measurement tests from independent laboratories. Prompted by environmental organizations, the Cadarache CLI commissioned a CRIIRAD (Commission de Recherche et d'Informations Independantes sur la Radioactivite) fact-finding survey in 2008-2009 to evaluate the environmental impact of the CEA/Cadarache installations since they were created. This study points to a moderate present impact, though a lack of data makes it impossible to reconstruct environmental impact prior to 1979. A set of guidelines are put forward to assess the past impact in greater detail and to lessen the current impact even further. Following this study, additional steps to minimize this impact will be taken by CEA/Cadarache inside the facilities, and by the relevant LCI outside the installations. Developing independent expert skills is a major challenge for CLIs to gain better knowledge of nuclear activities and improve their local management. (author)

  6. Is green economy achievable through championing green growth? A local government experience from Zambia

    Directory of Open Access Journals (Sweden)

    Phiri Rodgers

    2016-03-01

    Full Text Available The need to enhance environmental sustainability, sustainable development and growth that takes into account the well-being of the people and nature because of the increased production and consumption of goods and services is the major driver to the introduction of green economy in Zambia and countries in southern Africa. This article examines the extent to which local government in Zambia has embraced green growth and green economy and critically analyses the concept of green economy and green growth. This study is based on a review of planning and policy documents, a household questionnaire survey and interviews with various institutions, planners and rural development organisations. A number of policies implemented at the local government level were analysed and reflected upon irrespective of whether they contain the components of green growth and green economy and the extent to which they contribute to attaining green economy. The article argues that the need for economic diversification is important as far as green economy is concerned. The article recommends the need to invest in research and development in order to find more carbon-free economic activities. The conclusion is that local government is key to achieving green growth and green economy, because it is involved at all levels, from policy formulation to implementation.

  7. Condensational theory of stationary tornadoes

    International Nuclear Information System (INIS)

    Makarieva, A.M.; Gorshkov, V.G.; Nefiodov, A.V.

    2011-01-01

    Using the Bernoulli integral for air streamline with condensing water vapor a stationary axisymmetric tornado circulation is described. The obtained profiles of vertical, radial and tangential velocities are in agreement with observations for the Mulhall tornado, world's largest on record and longest-lived among the three tornadoes for which 3D velocity data are available. Maximum possible vortex velocities are estimated. -- Highlights: → Water vapor condensation causes a logarithmic drop of air pressure towards tornado center. → The first ever theoretical description of tornado velocities is obtained. → The maximum vortex velocity grows logarithmically with decreasing tornado eye radius. → Air motion with high velocities can only develop in sufficiently large condensation areas.

  8. Introduction. Cosmology meets condensed matter.

    Science.gov (United States)

    Kibble, T W B; Pickett, G R

    2008-08-28

    At first sight, low-temperature condensed-matter physics and early Universe cosmology seem worlds apart. Yet, in the last few years a remarkable synergy has developed between the two. It has emerged that, in terms of their mathematical description, there are surprisingly close parallels between them. This interplay has been the subject of a very successful European Science Foundation (ESF) programme entitled COSLAB ('Cosmology in the Laboratory') that ran from 2001 to 2006, itself built on an earlier ESF network called TOPDEF ('Topological Defects: Non-equilibrium Field Theory in Particle Physics, Condensed Matter and Cosmology'). The articles presented in this issue of Philosophical Transactions A are based on talks given at the Royal Society Discussion Meeting 'Cosmology meets condensed matter', held on 28 and 29 January 2008. Many of the speakers had participated earlier in the COSLAB programme, but the strength of the field is illustrated by the presence also of quite a few new participants.

  9. Dynamics of inhomogeneous chiral condensates

    Science.gov (United States)

    Carlomagno, Juan Pablo; Krein, Gastão; Kroff, Daniel; Peixoto, Thiago

    2018-01-01

    We study the dynamics of the formation of inhomogeneous chirally broken phases in the final stages of a heavy-ion collision, with particular interest on the time scales involved in the formation process. The study is conducted within the framework of a Ginzburg-Landau time evolution, driven by a free energy functional motivated by the Nambu-Jona-Lasinio model. Expansion of the medium is modeled by one-dimensional Bjorken flow and its effect on the formation of inhomogeneous condensates is investigated. We also use a free energy functional from a nonlocal Nambu-Jona-Lasinio model which predicts metastable phases that lead to long-lived inhomogeneous condensates before reaching an equilibrium phase with homogeneous condensates.

  10. Scrutinizing the pion condensed phase

    Energy Technology Data Exchange (ETDEWEB)

    Carignano, Stefano; Mammarella, Andrea; Mannarelli, Massimo [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Lepori, Luca [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, Coppito-L' Aquila (Italy); Pagliaroli, Giulia [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Gran Sasso Science Institute, L' Aquila (Italy)

    2017-02-15

    When the isospin chemical potential exceeds the pion mass, charged pions condense in the zero-momentum state forming a superfluid. Chiral perturbation theory provides a very powerful tool for studying this phase. However, the formalism that is usually employed in this context does not clarify various aspects of the condensation mechanism and makes the identification of the soft modes problematic. We re-examine the pion condensed phase using different approaches within the chiral perturbation theory framework. As a first step, we perform a low-density expansion of the chiral Lagrangian valid close to the onset of the Bose-Einstein condensation. We obtain an effective theory that can be mapped to a Gross-Pitaevskii Lagrangian in which, remarkably, all the coefficients depend on the isospin chemical potential. The low-density expansion becomes unreliable deep in the pion condensed phase. For this reason, we develop an alternative field expansion deriving a low-energy Lagrangian analog to that of quantum magnets. By integrating out the ''radial'' fluctuations we obtain a soft Lagrangian in terms of the Nambu-Goldstone bosons arising from the breaking of the pion number symmetry. Finally, we test the robustness of the second-order transition between the normal and the pion condensed phase when next-to-leading-order chiral corrections are included. We determine the range of parameters for turning the second-order phase transition into a first-order one, finding that the currently accepted values of these corrections are unlikely to change the order of the phase transition. (orig.)

  11. Excitations of Bose-Einstein condensates at finite temperatures

    International Nuclear Information System (INIS)

    Rusch, M.

    2000-01-01

    Recent experimental observations of collective excitations of Bose condensed atomic vapours have stimulated interest in the microscopic description of the dynamics of a Bose-Einstein condensate confined in an external potential. We present a finite temperature field theory for collective excitations of trapped Bose-Einstein condensates and use a finite-temperature linear response formalism, which goes beyond the simple mean-field approximation of the Gross-Pitaevskii equation. The effect of the non-condensed thermal atoms we include using perturbation theory in a quasiparticle basis. This presents a simple scheme to understand the interaction between condensate and non-condensed atoms and enables us to include the effect the condensate has on collision dynamics. At first we limit our treatment to the case of a spatially homogeneous Bose gas. We include the effect of pair and triplet anomalous averages and thus obtain a gapless theory for the excitations of a weakly interacting system, which we can link to well known results for Landau and Beliaev damping rates. A gapless theory for trapped systems with a static thermal component follows straightforwardly. We then investigate finite temperature excitations of a condensate in a spherically symmetric harmonic trap. We avoid approximations to the density of states and thus emphasise finite size aspects of the problem. We show that excitations couple strongly to a restricted number of modes, giving rise to resonance structure in their frequency spectra. Where possible we derive energy shifts and lifetimes of excitations. For one particular mode, the breathing mode, the effects of the discreteness of the system are sufficiently pronounced that the simple picture of an energy shift and width fails. Experiments in spherical traps have recently become feasible and should be able to test our detailed quantitative predictions. (author)

  12. Radiation education using local environment. Educational experiment using Misasa spring water

    International Nuclear Information System (INIS)

    Nakamura, Mariko; Esaka, Takao; Kamata, Masahiro

    2005-01-01

    Hoping that use of natural radioactivity as teaching materials helps learners to understand the existence of radiation in nature, the authors developed several kinds of safe and inexpensive experiments for elementary and junior high school education using hot spring water taken from Misasa, situated in Tottori prefecture, Japan. Here, they report the details of experimental procedure to observe the radioactive equilibrium between Rn 222 released from the hot spring water and its daughters as well as the decay after isolation from Rn 222. The experiment needs no hazardous chemicals nor Bunsen burners, and can be carried out in normal classrooms without any special apparatus. (S. Ohno)

  13. Minimum Leakage Condenser Test Program

    International Nuclear Information System (INIS)

    1978-05-01

    This report presents the results and analysis of tests performed on four critical areas of large surface condensers: the tubes, tubesheets, tube/tubesheet joints and the water chambers. Significant changes in operation, service duty and the reliability considerations require that certain existing design criteria be verified and that improved design features be developed. The four critical areas were treated analytically and experimentally. The ANSYS finite element computer program was the basic analytical method and strain gages were used for obtaining experimental data. The results of test and analytical data are compared and recommendations made regarding potential improvement in condenser design features and analytical techniques

  14. Vortex dynamics in coherently coupled Bose-Einstein condensates

    Science.gov (United States)

    Calderaro, Luca; Fetter, Alexander L.; Massignan, Pietro; Wittek, Peter

    2017-02-01

    In classical hydrodynamics with uniform density, vortices move with the local fluid velocity. This description is rewritten in terms of forces arising from the interaction with other vortices. Two such positive straight vortices experience a repulsive interaction and precess in a positive (anticlockwise) sense around their common centroid. A similar picture applies to vortices in a two-component, two-dimensional uniform Bose-Einstein condensate (BEC) coherently coupled through rf Rabi fields. Unlike the classical case, however, the rf Rabi coupling induces an attractive interaction and two such vortices with positive signs now rotate in the negative (clockwise) sense. Pairs of counter-rotating vortices are instead found to translate with uniform velocity perpendicular to the line joining their cores. This picture is extended to a single vortex in a two-component trapped BEC. Although two uniform vortex-free components experience familiar Rabi oscillations of particle-number difference, such behavior is absent for a vortex in one component because of the nonuniform vortex phase. Instead the coherent Rabi coupling induces a periodic vorticity transfer between the two components.

  15. A single centre experience with sequential and concomitant chemoradiotherapy in locally advanced stage IV tonsillar cancer

    Directory of Open Access Journals (Sweden)

    Coyle Catherine

    2010-12-01

    Full Text Available Abstract Background Chemo-radiotherapy offers an alternative to primary surgery and adjuvant therapy for the management of locally advanced stage IV squamous cell carcinomas of the tonsil. Methods A retrospective analysis was performed of the outcomes of 41 patients with locoregionally advanced squamous cell carcinoma of the tonsil treated non-surgically at the Yorkshire Cancer Centre between January 2004 and December 2005. Due to long radiotherapy waiting times, patients received induction chemotherapy with cisplatin and 5-fluorouracil followed by either cisplatin concurrent chemoradiotherapy or radiotherapy alone. Results Median age was 55 years (range 34-76 years and 28 (68% patients were male. 35/41 patients (85% received 2 or more cycles of induction chemotherapy. Following induction chemotherapy, 32/41 patients (78% had a clinical response. Concomitant chemotherapy was given to 30/41 (73%. All patients received the planned radiotherapy dose with no delays. There were no treatment related deaths. Six (15% patients had gastrostomy tubes placed before treatment, and 22 (54% required nasogastric tube placement during or after treatment for nutritional support. 17 patients required unplanned admissions during treatment for supportive care. At 4 months post treatment assessment 35 out of 41 (85% patients achieved complete clinical and radiographic response. Median follow-up is 38 months (8-61 months. Local and regional control rate in complete responders at 3 years was 91%. Distant metastases have been found in 4 (9.8% patients. Three year progression-free survival rate in all patients is 75%. The 3-year cause specific survival and overall survival are 75% and 66% respectively. Conclusion Cisplatin-based induction and concurrent chemoradiotherapy provides excellent tumour control with acceptable toxicity for patients with locally advanced tonsillar cancer.

  16. Transition to instability in a kicked Bose-Einstein condensate

    International Nuclear Information System (INIS)

    Zhang Chuanwei; Raizen, Mark G.; Liu Jie; Niu Qian

    2004-01-01

    A periodically kicked ring of a Bose-Einstein condensate is considered as a nonlinear generalization of the quantum kicked rotor. For weak interactions between atoms, periodic motion (antiresonance) becomes quasiperiodic (quantum beating) but remains stable. There exists a critical strength of interactions beyond which quasiperiodic motion becomes chaotic, resulting in an instability of the condensate manifested by exponential growth in the number of noncondensed atoms. Similar behavior is observed for dynamically localized states (essentially quasiperiodic motions), where stability remains for weak interactions but is destroyed by strong interactions

  17. Mitotic chromosome condensation in vertebrates

    International Nuclear Information System (INIS)

    Vagnarelli, Paola

    2012-01-01

    Work from several laboratories over the past 10–15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292–301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories—a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307–316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119–1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579–589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different

  18. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  19. Present it like it is here: Creating local presence to improve online product experiences

    NARCIS (Netherlands)

    Verhagen, Tibert; Vonkeman, Charlotte; Feldberg, Frans; Verhagen, Pleunes Willem

    2014-01-01

    Advanced online product presentation technologies such as virtual mirrors enable consumers to experience products like they are actually present with them in the real world. This study is one of the first to address the mechanism underlying this phenomenon. Inspired by literature on media technology

  20. Teaching Global Change in Local Places: The HERO Research Experiences for Undergraduates Program

    Science.gov (United States)

    Yarnal, Brent; Neff, Rob

    2007-01-01

    The Human-Environment Research Observatory (HERO) Research Experience for Undergraduates (REU) program aimed to develop the next generation of researchers working on place-based human-environment problems. The program followed a cooperative learning model to foster an integrated approach to geographic research and to build collaborative research…

  1. Dose escalation by hypo fractionation in localized prostate cancer - a large single institution experience

    International Nuclear Information System (INIS)

    Mahadevan, A.; Klein, E.; Kupelian, P.

    2003-01-01

    To report the outcomes of high dose radiation therapy using Intensity Modulated Radiation Therapy (IMRT) with hypo fractionation in localized prostate cancer at the Cleveland Clinic Foundation. A total of 278 patients with localized prostate cancer were treated with IMRT between 1998 and 2001. All cases had available pretreatment PSA (iPSA) and biopsy Gleason scores (bGS), no nodal metastasis, a minimum 2 year follow-up, and >5 follow-up PSA levels. The frequency by T-stage was: T1-T2A in 86%, T2B-T2C in 9%, and T3 in 5%. The median iPSA was 8.35. The frequency by bGS was: =7 in 45%. The age range for the patients was from 48 to 85 years (median 68 years). The median follow-up was 33 months (range: 24-49 months). The median doses delivered were 83Gy (delivered at 2.5Gy per fraction to 70 Gy; this being equivalent to 83 Gy at standard fractionation of 1.8 Gy using an alpha/beta of 2). The ASTRO definition for biochemical failure was used. Toxicity was assessed using Radiation Therapy Oncology Group (RTOG) criteria. The 3-year biochemical relapse free survival (bRFS) for the entire cohort at three years was 91%. Any (grade 1 or higher) acute genito-urinary (GU) side effects were seen in 79% of patients. Grade 2 or higher acute GU toxicity was seen in 18% of patients. Any (grade 1 or higher) acute gastro-intestinal (GI) side effects were seen in 65% of patients. Grade 2 or higher acute GI toxicity was seen in 11% of patients. Any (grade 1 or higher) late GU side effects were seen in 3% of patients. Grade 2 or higher late GU toxicity was seen in 1.5% of patients. Any (grade 1 or higher) late GI side effects were seen in 13% of patients. Grade 2 or higher late GI toxicity was seen in 5% of patients. Higher doses of radiation delivered by IMRT resulted in excellent bRFS outcomes in patients with localized prostate cancer receiving external beam radiation therapy. IMRT can be effectively used to safely increase dose delivery without compromising on quality of life

  2. Advantages of carotid endarterectomy under local anaesthesia with minimal cerebral monitoring: an experience of 45 cases

    International Nuclear Information System (INIS)

    Bajwa, S.P.; Jameel, M.; Masood, N.

    2014-01-01

    Objective: To evaluate the benefits, efficacy and safety of local cervical plexus block in the performance of carotid endarterectomy, in the absence of sophisticated cerebral perfusion monitoring. Place and Duration of Study: This study was carried out at Combined Military Hospital (CMH) Lahore, Pakistan from January 2012 to May 2013. Study Design: Quasi-experimental study. Patients and Methods: A total of 45 cases of ASA II and ASA III physical status were operated for carotid endarterectomy under local block of cervical plexus. After thorough preanaesthetic assessment, the patients physical conditions were optimized before surgery. Premedication was given with midazolam and sedated during operation with small doses of propofol. Local anaesthesia (LA) was completed by injecting bupivacaine in cervical plexuses 2, C3 and C4 areas. During operation vital signs and adequacy of cerebral perfusion were monitored by keeping the patient awake and making clinical neurological observations. Verbal contact was maintained with the patient. Breathing patterns and motor power were assessed in contralateral upper and lower limbs. Postoperatively patients were interviewed and analgesia during operation was assessed with visual analogue scale. Surgeon's satisfaction regarding intraoperative analgesia was also noted. Patients who required added sedation or local anesthetic agent were also noted. Average duration of surgery time was two hours and average stay of the patients in hospital was five days. Results: Out of 45 patients, 37 patients (82%) had smooth and comfortable anaesthesia and analgesia. In only 1 patient (2.2%) LA had to be converted into general anaesthesia (GA). In 3 cases (7%) LA was supplemented. One patient (2.2%) developed hoarseness and difficulty in breathing and 1 patient (2.2%) developed hemiparesis intra-operatively; while 1 patient (2.2%) developed hypotension in the immediate postoperative period. One patient (2.2%) developed haematoma at infiltration

  3. Connecting transport, agriculture and rural development: Experiences from Mhlontlo local municipality integrated infrastructure atlas

    CSIR Research Space (South Africa)

    Chakwizira, J

    2010-08-01

    Full Text Available school and clinic established by the company. The project generated many connections with small local enterprises during the construction and operational phases. • Future plans include expanding production on a new site, for which a community... for the majority of the rural poor • Source of livelihood for an estimated 86 percent of rural people • Provides jobs for 1.3 billion small holders and landless workers • Foundation for viable rural communities • Of the developing World’s 5.5 billion...

  4. Calculation of the emergency condenser of the indirect cycle reactor CAREM

    International Nuclear Information System (INIS)

    Walter, D.; Schaffrath, A.

    2002-08-01

    CAREM is an Argentine project to achieve the development, design and construction of an innovative, simple and small Nuclear Power Plant (NPP). This NPP has an indirect cycle reactor with some distinctive and characteristic features (e.g. integrated primary cooling system by natural circulation, self-pressurized primary system and passive safety systems, etc.). In the frame of an IAEA forwarded HUMAN RESOURCES DEVELOPMENT - 'Advice on CAREM passive emergency condenser' at the Centro Atomico in San Carlos de Bariloche (Argentina) German experimental as well as analytical investigations of passive safety systems - mainly performed at the research centers Juelich and Rossendorf - were presented. During this visit it was decided that FZR should determine the emergency condenser capacity by using the ATHLET code with and without the condensation module extension KONWAR (condensation inside horizontal tube). These results should be compared and assessed with existing RELAP calculations. The ATHLET and ATHLET/KONWAR calculations of the emergency condenser were used for minimizing the user influence performed with exactly the same nodalization scheme and the same initial and boundary conditions than the RELAP calculations. The comparison of all three computational results shows that the required condenser capacities were achieved. The magnitudes were in order of up to 12%. An additionally performed evaluation of local flow parameters show large deviations especially for the heat transfer coefficients at the inner and outer tube wall. Due to the good validation progress of KONWAR by an extensive module validation against NOKO and HORUS experiments, the focus of the further investigation were concentrated on the boiling heat transfer. A comparison of the ATHLET boiling model (according to Forster and Zuber in combination with the equation of Thom for the determination of temperature difference between wall and saturated fluid) with other models from literature (Borishansky

  5. Improving the antimicrobial properties of titanium condenser material by surface modification using nanotechnology

    International Nuclear Information System (INIS)

    George, Rani P.; Dash, S.; Krishnan, R.; Kamruddin, M.; Kalavathi, S.; Tyagi, A.K.; Manoharan, N.; Dayal, R.K.; Vishwakarma, Vinita; Theresa, Josephine

    2008-01-01

    Biofouling is one of the major problems faced by condenser materials of power plants using seawater for cooling. Fouling control strategies in condensers include a combination of mechanical and chemical treatments like sponge ball cleaning, back washing and chlorination. In general, numerous studies have shown that no routine treatment regime can successfully keep the condenser tube clean over a period extending to years. Surface properties of the substratum influence initial adhesion and growth of bacterial cells on materials, modification of the surface for mitigating microbial attachment is the need of the hour. Metal nanoparticles are known to exhibit enhanced physical and chemical properties when compared to their bulk counter parts because of their high surface to volume ratios. Metals like copper are very toxic to microorganisms and effectively kill most of the microbes by blocking the respiratory enzyme. Copper alloys with their excellent resistance to biofouling are used extensively for marine applications. However, they are prone to localized corrosion initiation and consequently are getting replaced by extremely corrosion resistant titanium. Still, the inertness and biocompatibility of titanium makes it very susceptible to biofouling. Hence, this study attempts to use nano technology methods of surface modification of titanium using thin film of copper and also multilayers and bilayers of copper and nickel. This is aimed at improving the antimicrobial properties of this condenser pipe material. These nano structured thin films have been grown on titanium substrate using pulsed DC magnetron-sputtering and pulsed laser deposition. The thin films were characterized using Atomic Force Microscopy (AFM), Glancing Incidence X-ray Diffraction (GIXRD) and scanning electron microscopy (SEM with EDAX analysis). Antimicrobial properties were evaluated by exposure studies in seawater and bacterial cultures and by post exposure analysis using culture and

  6. Investigation of Interfacial Phenomena During Condensation of Humid Air on a Horizontal Substrate

    Directory of Open Access Journals (Sweden)

    Tiwari Akhilesh

    2013-12-01

    Full Text Available The condensation phenomenon of humid air on solid substrates can occur in many applications, and it is known as one of the most difficult problem to deal with for the improvement of the quality of air in a closed environment. The present study was motivated by the investigation of the coupling between ventilation and condensation inside controlled ecological life support systems (CELSS, as it has an important role for higher plants growth in greenhouses and living conditions in manned spacecraft cabins, particularly in long duration space flights or in future space bases. It is well known that the enhancement of the gas exchange with leaves and the growth of plants are dependent on the organoleptic and/or the surrounding thermo-physical factors. Insufficient air movement around plants and condensation on plant leaves generally limit their growth by suppressing the gas diffusion in the leaf boundary-layer thereby decreasing photosynthetic and transpiration rates. Thus, the optimization of a CELSS will require the control of the airflow and concomitant gas/liquid transfer at the plant surfaces. The experimental and theoretical modeling of CELSS requires a comprehensive understanding of the micro to the macro levels of liquid gas phase transfer. Hence, an experimental set-up was developed at 1-g to evaluate the mass transfer coefficients due to condensation of humid air on specific geometries in well controlled environmental conditions. The goal was to establish correlations between the fluxes of mass and heat, the relative humidity and the mean flow for the development of theoretical models based on local transfer coefficients. The experiments were performed at ambient temperature, with a relative humidity between 35-70% and for a velocity range of 1.0-3.0 m.s−1.

  7. Grassroots volunteers in context: rewarding and adverse experiences of local women working on HIV and AIDS in Kilimanjaro, Tanzania.

    Science.gov (United States)

    Corbin, J Hope; Mittelmark, Maurice B; Lie, Gro T

    2016-09-01

    Many nongovernmental organizations in Africa rely on grassroots volunteers to provide critical health services. Considering context and the interplay of individual, organizational, and societal influences on the experience of volunteers, this paper addresses three questions: What do grassroots volunteers contribute? What organizational processes promote volunteer engagement? What are the positive and negative consequences of volunteering? Eighteen members and staff of the Tanzanian HIV and AIDS NGO, KIWAKKUKI, were selected from 6000+ women volunteers to be interviewed. The interviews were recorded, transcribed, and analyzed for themes. Within KIWAKKUKI, volunteers contributed time and local knowledge, leading to an indigenous educational approach building on local norms and customs. Volunteers' engagement was motivated by the desire to support family members, reverse stigma, and work/socialize with other women. Benefits to volunteers included skills acquisition and community recognition; yet some volunteers also reported negative experiences including burnout, conferred stigma, and domestic violence. Positive organizational processes built on cultural practices such as collective decision-making and singing. The findings point to important considerations about context, including the synergistic effect training can have on local traditions of caring, complications of gender inequity, and how community health planning processes may need to be modified in extremely poor settings. This research also suggests good utility of the research framework (the Bergen Model of Collaborative Functioning) that was used to analyze volunteer engagement for service delivery in sub-Saharan contexts. © The Author(s) 2015.

  8. Review of Proximal Nail Antirotation (PFNA and PFNA-2 – Our Local Experience

    Directory of Open Access Journals (Sweden)

    WL Loo

    2011-07-01

    Full Text Available The proximal femoral nail antirotation (PFNA device was recently introduced as an option for intramedullary management of pertrochanteric hip fractures. We report here local results with this relatively new implant. Sixty-two patients with pertrochanteric or subtrochanteric fractures underwent intramedullary fixation with PFNA devices in our centre during the 14 month period from September 2008 to October 2009. Data for this report were retrieved from clinical case records and operative notes. We recorded the age, gender, length of stay and operative time, preoperative ambulatory status and days required to regain mobility. Fractures were classified using the AO classification (A1, A2 and A3. Complications were also identified.There were 15 male and 47 female patients and the mean age was 74.3 years. The mean surgical duration was 76.1min and the average length of hospitalisation was 14.5 days. Five cases were noted to have femoral shaft fracture and no occurrences of screw cutout. We found that 83.9% of the patients were able to regain preoperative mobility status by 6 months following surgery. We conclude that the PFNA is an effective implant for stabilisation of proximal hip fractures and that the local complication rate is similar to reports from other centres.

  9. An intelligent stand-alone ultrasonic device for monitoring local structural damage: implementation and preliminary experiments

    International Nuclear Information System (INIS)

    Pertsch, Alexander; Kim, Jin-Yeon; Wang, Yang; Jacobs, Laurence J

    2011-01-01

    Continuous structural health monitoring has the potential to significantly improve the safety management of aged, in-service civil structures. In particular, monitoring of local damage growth at hot-spot areas can help to prevent disastrous structural failures. Although ultrasonic nondestructive evaluation (NDE) has proved to be effective in monitoring local damage growth, conventional equipment and devices are usually bulky and only suitable for scheduled human inspections. The objective of this research is to harness the latest developments in embedded hardware and wireless communication for developing a stand-alone, compact ultrasonic device. The device is directed at the continuous structural health monitoring of civil structures. Relying on battery power, the device possesses the functionalities of high-speed actuation, sensing, signal processing, and wireless communication. Integrated with contact ultrasonic transducers, the device can generate 1 MHz Rayleigh surface waves in a steel specimen and measure response waves. An envelope detection algorithm based on the Hilbert transform is presented for efficiently determining the peak values of the response signals, from which small surface cracks are successfully identified

  10. Local mandate improves equity of paid sick leave coverage: Seattle’s experience

    Directory of Open Access Journals (Sweden)

    Jennifer L. Romich

    2017-01-01

    Full Text Available Abstract Background Paid sick leave allows workers to take time off work for personal or family health needs, improving health and potentially limiting infectious diseases. The U.S. has no national sick leave mandate, and many American workers - particularly those at lower income levels - have no right to paid time off for their own or family members’ health needs. This article reports on outcomes of a local mandate, the City of Seattle Paid Sick and Safe Time Ordinance, which requires certain employers to provide paid sick leave to eligible workers. Methods Survey collectors contacted a stratified random sample of Seattle employers before the Ordinance went into effect and one year later. Pre- and post- analysis draws on responses to survey items by 345 employers who were subject to the paid sick leave mandate. Results Awareness of the policy and provision of paid leave grew significantly over the year after the Ordinance was enacted. More employers offered leave to full-time workers (80.8 to 93.9%, p < .001 and part-time workers (47.1 to 66.7%, p < .001 with particularly large increases in the hospitality sector, which includes food workers (coverage of any hospitality employee: 27.5 to 85.0%, p < .001. Conclusions Absent a federal policy, local paid sick time mandates can increase paid sick leave coverage, an important social determinant of health.

  11. Experiment-based modelling of hardening and localized plasticity in metals irradiated under cascade damage conditions

    International Nuclear Information System (INIS)

    Singh, B.N.; Ghoniem, N.M.; Trinkaus, H.

    2002-01-01

    The analysis of the available experimental observations shows that the occurrence of a sudden yield drop and the associated plastic flow localization are the major concerns regarding the performance and lifetime of materials exposed to fission or fusion neutrons. In the light of the known mechanical properties and microstructures of the as-irradiated and irradiated and deformed materials, it has been argued that the increase in the upper yield stress, the sudden yield drop and the initiation of plastic flow localization, can be rationalized in terms of the cascade induced source hardening (CISH) model. Various aspects of the model (main assumptions and predictions) have been investigated using analytical calculations, 3-D dislocation dynamics and molecular dynamics simulations. The main results and conclusions are briefly summarized. Finally, it is pointed out that even though the formation of cleared channels may be rationalized in terms of climb-controlled glide of the source dislocation, a number of problems regarding the initiation and the evolution of these channels remain unsolved

  12. Experiment-based modelling of hardening and localized plasticity in metals irradiated under cascade damage conditions

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N. E-mail: bachu.singh@risoe.dk; Ghoniem, N.M.; Trinkaus, H

    2002-12-01

    The analysis of the available experimental observations shows that the occurrence of a sudden yield drop and the associated plastic flow localization are the major concerns regarding the performance and lifetime of materials exposed to fission or fusion neutrons. In the light of the known mechanical properties and microstructures of the as-irradiated and irradiated and deformed materials, it has been argued that the increase in the upper yield stress, the sudden yield drop and the initiation of plastic flow localization, can be rationalized in terms of the cascade induced source hardening (CISH) model. Various aspects of the model (main assumptions and predictions) have been investigated using analytical calculations, 3-D dislocation dynamics and molecular dynamics simulations. The main results and conclusions are briefly summarized. Finally, it is pointed out that even though the formation of cleared channels may be rationalized in terms of climb-controlled glide of the source dislocation, a number of problems regarding the initiation and the evolution of these channels remain unsolved.

  13. Clinical experience of a new retractable barb needle for breast lesion localization: The first 60 cases

    International Nuclear Information System (INIS)

    Urrutia, E.J.; Hawkins, I.F.; Hawkins, M.C.; Meacham, M.A.; Bland, K.I.; Copelan, E.M. III.

    1987-01-01

    Recently there has been an increase in the request to the radiologists from surgeons to localize nonpalpable breast lesions suspicious for malignancy. Currently there are several needles used for this purpose. The authors present here a new retractable barb needle which consists of a coaxial system with a 20-gauge outer cannula and a 23-gauge inner cannula with a sharp stylus with a hook spring wire soldered to it. The main advantage of this needle over other systems is the ability of the barb to be retracted and the needle repositioned. Other advantages are the strong anchoring properties of the barb, permitting retraction by the surgeon and ending fear of dislodgement, breaking, or transection as experienced with other systems. This system also lowers the radiation exposure to the patients since only one confirmatory radiograph is necessary after optimal positioning of the needle as opposed to two with the most popular system used currently. The authors have done 60 localizations in 58 patients with no failures or major complications. The area in question was successfully sampled in all cases. The authors' referring surgeons prefer this needle over other commercially available types

  14. Perspectives of Complexity in Water Governance: Local Experiences of Global Trends

    Directory of Open Access Journals (Sweden)

    Michele-Lee Moore

    2013-10-01

    Full Text Available Those responsible for water governance face great complexity. However, the conceptualisations of what comprises that complexity have been broad and inconsistent. When efforts are made to address the complexity in water governance, it is unclear whether the problems and the related solutions will be understood across the actors and institutions involved. This paper provides a review of the literature focused on global water governance to discern core themes that commonly characterise discussions of complexity. It then considers how the consequences of these issues are manifested at the local scale through an examination of empirical research of the Murray-Darling Basin Authority and the Prachinburi River Basin Committee. The results demonstrate that a history of a technical, depoliticised discourse is often perceived to contribute to complexity. The consequence is that when a severe ecological disturbance occurs within a river basin with poorly understood causes, few tools are available to support river basin organisations to address the political nature of these challenges. Additionally, a lack of clear authority structures has been recognised globally, but locally this can contribute to conflict amongst the 'governors' of water. Finally, a range of contested definitions and governance frameworks exists that contributes to complexity, but confronting the diversity of perspectives can lead to ethical dilemmas given that the decisions will affect the health and livelihoods of basin communities.

  15. Metropolization Process for enhancing local and regional planning : an experience of cirebon metropolitan, West Java

    Science.gov (United States)

    Supriyadi Rustidja, E.

    2018-03-01

    Metropolitan develops in line with resource utilization, investment, and transactions of regional activities. Metropolization of an area gives emerge urban economy that changes the situation, form, and pattern of urban space interactions. On the other hand, metropolism concerns the strategy of changing variation of urban space, so that metropolitan invasion not only form of urban space but also the process of interaction among stakeholders in developing metropolitan area. Based on participatory research, this article explores metropolitan invasion process for enhancing local and regional planning, both indigenous and intrusive cataclysmic. The study find that the primeval, rural, and urban as elemental environment must be considered in developing metropolitan, not merely form the structure and pattern of urban space. The metropolization process also requires the strategic of rural urban linkage, context setting and local assessment, strategic community investment, and interculturalist approach. The other findings of the study show that metropolization in Cirebon Metropolitan, West Java emphasizing on promotion of competitiveness strategy, value chain urban activities, and networking of urban areas. Cirebon Metropolitan must promote the realization of growth centers and connect the interregional activities of metropolitan area for providing sustainable economic growth.

  16. Combining partial liver resection and local ablation of liver tumours: a preliminary Dutch experience

    Directory of Open Access Journals (Sweden)

    van Gulik Thomas M

    2006-07-01

    Full Text Available Abstract Background The combination of partial liver resection and radiofrequency ablation (RFA is a novel concept in the treatment of unresectable liver malignancies. The aim of this study is to evaluate the results of this combined strategy in the Netherlands. Methods Thirty-five patients treated with a combination of partial liver resection and RFA were identified from a prospectively registered pooled multicentre database. All patients were operated between June 1999 and November 2003 in 8 medical centres in the Netherlands. Main outcome parameters were morbidity, mortality, local success rate, and survival. Results Thirty-seven operations were performed in 35 patients. The group consisted of 20 male and 15 female patients with a median age of 59 years (range 41–76. Seventy-six lesions were resected and RFA was performed to ablate 82 unresectable liver tumours. Twelve patients developed a total of 24 complications, resulting in an overall perioperative morbidity rate of 32%. In two patients major complications resulted in postoperative death (postoperative mortality rate 5.4%. Local success rate after RFA was 88% and the estimated 1-, 2- and 3-year overall survival rates were 84%, 70% and 43%, respectively. Conclusion This strategy should only be performed following strict patient selection and within the context of prospective clinical trials.

  17. Non-local model analysis of heat pulse propagation and simulation of experiments in W7-AS

    International Nuclear Information System (INIS)

    Iwasaki, Takuya; Itoh, Sanae-I.; Yagi, Masatoshi; Itoh, Kimitaka; Stroth, U.

    1999-01-01

    A new model equation which includes the non-local effect in the hear flux is introduced to study the transient transport phenomena. A non-local heat flux, which is expressed in terms of the integral equation, is superimposed on the conventional form of the heat flux. This model is applied to describe the experimental results from the power switching [U. Stroth et al.: Plasma Phys. Control. Fusion 38 (1996) 1087] and the power modulation experiments [L. Giannone et al.: Nucl. Fusion 32 (1992) 1985] in the W7-AS stellarator. A small fraction of non-local component in the heat flux is found to be very effective in modifying the response against an external modulation. The transient feature of the transport property, which are observed in the response of heat pulse propagation, are qualitatively reproduced by the transport simulations based on this model. A possibility is discussed to estimate the correlation length of the non-local effect experimentally by use of the results of transport simulations. (author)

  18. Development and Optimization of Polymeric Self-Emulsifying Nanocapsules for Localized Drug Delivery: Design of Experiment Approach

    Directory of Open Access Journals (Sweden)

    Jyoti Wadhwa

    2014-01-01

    Full Text Available The purpose of the present study was to formulate polymeric self-emulsifying curcumin nanocapsules with high encapsulation efficiency, good emulsification ability, and optimal globule size for localized targeting in the colon. Formulations were prepared using modified quasiemulsion solvent diffusion method. Concentration of formulation variables, namely, X1 (oil, X2 (polymeric emulsifier, and X3 (adsorbent, was optimized by design of experiments using Box-Behnken design, for its impact on mean globule size (Y1 and encapsulation efficiency (Y2 of the formulation. Polymeric nanocapsules with an average diameter of 100–180 nm and an encapsulation efficiency of 64.85 ± 0.12% were obtained. In vitro studies revealed that formulations released the drug after 5 h lag time corresponding to the time to reach the colonic region. Pronounced localized action was inferred from the plasma concentration profile (Cmax 200 ng/mL that depicts limited systemic absorption. Roentgenography study confirms the localized presence of carrier (0–2 h in upper GIT; 2–4 h in small intestine; and 4–24 h in the lower intestine. Optimized formulation showed significantly higher cytotoxicity (IC50 value 20.32 μM in HT 29 colonic cancer cell line. The present study demonstrates systematic development of polymeric self-emulsifying nanocapsule formulation of curcumin for localized targeting in colon.

  19. Secret Shopping is an Effective Tool for Identifyings in Library User Experience Local Pattern

    Directory of Open Access Journals (Sweden)

    Kelley Wadson

    2016-12-01

    Full Text Available A Review of: Boyce, C. M. (2015. Secret shopping as user experience assessment tool. Public Services Quarterly, 11(4, 237-253. doi:10.1080/15228959.2015.1084903 Objective – To assess library user experience (UX at two entry-level service desks to determine the need for, and inform the aspects in which to improve, services and staff training. Design – Observational study using secret shopping. Setting – A small, private university in Illinois, United States of America. Subjects – Library employees, comprised primarily of student assistants; and 11 secret shoppers, comprised of 5 faculty members, 4 staff members, and 2 first-year students from the university.

  20. Designing Shared Virtual Reality Gaming Experiences in Local Multi-platform Games

    OpenAIRE

    Liszio , Stefan; Masuch , Maic

    2016-01-01

    Part 4: Short Papers; International audience; Designing multiplayer virtual reality games is a challenging task since immersion is easily destroyed by real world influences. However, providing fun and social virtual reality experiences is inevitable for establishing virtual reality gaming as a convincing new medium. We propose a design approach to integrate social interactions into the game design while retaining immersion, and present design methods to implement this approach. Furthermore, w...

  1. GLOBAL AND LOCAL COUPLING COMPENSATION EXPERIMENTS IN RHIC USING AC DIPOLES

    International Nuclear Information System (INIS)

    CALAGA, R.; FRANCHI, A., TOMAS, R.; CERN)

    2006-01-01

    Compensation of transverse coupling during the RHIC energy ramp has been proven to be non-trivial and tedious. The lack of accurate knowledge of the coupling sources has initiated several efforts to develop fast techniques using turn-by-turn BPM data to identify and compensate these sources. This paper aims to summarize the beam experiments performed to measure the coupling, matrix and resonance driving terms with the aid of RHIC ac dipoles at injection energy

  2. Vaginal birth after cesarean section—The world trend and local experience in Taiwan

    OpenAIRE

    Hsiu-Ting Tsai; Chia-Hsun Wu

    2017-01-01

    Objective: The trend of increasing cesarean section rates had evoked worldwide attention. Many approaches were introduced to diminish cesarean section rates. Vaginal birth after cesarean section (VBAC) is a route of delivery with diverse agreements. In this study, we try to reveal the world trend in VBAC and our experience of a 10-year period in a medical center in northern Taiwan. Materials and methods: This is a retrospective study of all women who underwent elective repeat cesarean deli...

  3. Recent experiences in the development of locally-produced ready to use foods

    International Nuclear Information System (INIS)

    Ryan, Kelsey; Manary, Mark

    2014-01-01

    Ready-to-use foods for treatment of moderate acute malnutrition (MAM) are micronutrient-fortified, lipid pastes containing roasted peanuts, oil, micronutrients, sugar, soy and/or dairy ingredient powders. The benefits of pastes like ready-to-use therapeutic food (RUTF), ready-to-use supplementary food (RUSF), and lipid nutrient supplements (LNS) for the treatment of nutritional maladies are that they are shelf-stable due to their low water activity, they are easily transportable, and they can be eaten as-is. Since the development of ready-to-use foods, cost reduction and local production experimentation have been ongoing. Attempts to replace ingredients like skim milk powder with alternate dairy protein ingredients or non-animal ingredients have been reported, but little food and process development information has been revealed. Linear programming or least-cost optimization mathematical models have been employed to help design low cost paste formulas from a selection of ingredients that also meet nutritional requirements. A new user-friendly tool can be used to develop new formulas that incorporate locally-sourced ingredients. New approaches to ingredient utilization are necessary for future ready-to-use food production and will require the development of novel processes for local ingredients compared to traditional pastes. The challenges of incorporating novel ingredients include processing changes, flavor and acceptability, and meeting nutrient requirements. Our research is designed to not only look at substitute ingredients, but also to optimize processing conditions in order to reduce cost by energy savings, extended shelf-life, and lower nutrient degradation. An RUSF using a novel dairy ingredient, whey permeate, was recently developed and is currently being tested in a prospective, double-blind randomized clinical trial for children with MAM in Malawi. Recent research in the development and testing of ready-to-use foods for MAM include a programmatic study

  4. On condensation-induced waves

    NARCIS (Netherlands)

    Cheng, W.; Luo, X.; Dongen, van M.E.H.

    2010-01-01

    Complex wave patterns caused by unsteady heat release due to cloud formation in confined compressible flows are discussed. Two detailed numerical studies of condensation-induced waves are carried out. First, the response of a flow of nitrogen in a slender Laval nozzle to a sudden addition of water

  5. KAON CONDENSATION IN NEUTRON STARS

    International Nuclear Information System (INIS)

    RAMOS, A.; SCHAFFNER-BIELICH, J.; WAMBACH, J.

    2001-01-01

    We discuss the kaon-nucleon interaction and its consequences for the change of the properties of the kaon in the medium. The onset of kaon condensation in neutron stars under various scenarios as well its effects for neutron star properties are reviewed

  6. Thermodynamic entanglement of magnonic condensates

    Science.gov (United States)

    Yuan, H. Y.; Yung, Man-Hong

    2018-02-01

    Over the past decade, significant progress has been achieved to create Bose-Einstein condensates (BECs) of magnetic excitations, i.e., magnons, at room temperature, which is a novel quantum many-body system with a strong spin-spin correlation, and contains potential applications in magnonic spintronics. For quantum information science, the magnonic condensates can become an attractive source of quantum entanglement, which plays a central role in most of the quantum information processing tasks. Here we theoretically study the entanglement properties of a magnon gas above and below the condensation temperature. We show that the thermodynamic entanglement of the spins is a manifestation of the off-diagonal long-range order; the entanglement of the condensate does not vanish, even if the spins are separated by an infinitely long distance, which is fundamentally distinct from the normal magnetic ordering below the Curie temperature. In addition, the phase-transition point occurs when the derivative of the entanglement changes abruptly. These results provide a theoretical foundation for a future investigation of the magnon BEC in terms of quantum entanglement.

  7. Rotary condenser for SC2

    CERN Multimedia

    1975-01-01

    During 1975 the SC2 performance was improved among other things by redesigning some of the elements of the ROTCO (Annual Report 1975, p. 55). The photo shows an interior wiew of the housing of the rotary condenser and of the sixteen sets of shaped stator blades.

  8. Approaching Bose-Einstein Condensation

    Science.gov (United States)

    Ferrari, Loris

    2011-01-01

    Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…

  9. Direct contact condensation induced transition from stratified to slug flow

    International Nuclear Information System (INIS)

    Strubelj, Luka; Ezsoel, Gyoergy; Tiselj, Iztok

    2010-01-01

    Selected condensation-induced water hammer experiments performed on PMK-2 device were numerically modelled with three-dimensional two-fluid models of computer codes NEPTUNE C FD and CFX. Experimental setup consists of the horizontal pipe filled with the hot steam that is being slowly flooded with cold water. In most of the experimental cases, slow flooding of the pipe was abruptly interrupted by a strong slugging and water hammer, while in the selected experimental runs performed at higher initial pressures and temperatures that are analysed in the present work, the transition from the stratified into the slug flow was not accompanied by the water hammer pressure peak. That makes these cases more suitable tests for evaluation of the various condensation models in the horizontally stratified flows and puts them in the range of the available CFD (Computational Fluid Dynamics) codes. The key models for successful simulation appear to be the condensation model of the hot vapour on the cold liquid and the interfacial momentum transfer model. The surface renewal types of condensation correlations, developed for condensation in the stratified flows, were used in the simulations and were applied also in the regions of the slug flow. The 'large interface' model for inter-phase momentum transfer model was compared to the bubble drag model. The CFD simulations quantitatively captured the main phenomena of the experiments, while the stochastic nature of the particular condensation-induced water hammer experiments did not allow detailed prediction of the time and position of the slug formation in the pipe. We have clearly shown that even the selected experiments without water hammer present a tough test for the applied CFD codes, while modelling of the water hammer pressure peaks in two-phase flow, being a strongly compressible flow phenomena, is beyond the capability of the current CFD codes.

  10. Experience of wireless local area network in a radiation oncology department.

    Science.gov (United States)

    Mandal, Abhijit; Asthana, Anupam Kumar; Aggarwal, Lalit Mohan

    2010-01-01

    The aim of this work is to develop a wireless local area network (LAN) between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc) for efficient patient data management and to made easy the availability of information (chair side) to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops) and stationary workstations, all equipped with wireless-fidelity (Wi-Fi) access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ) has been used. The wireless networking was configured with the Service Set Identifier (SSID), Media Access Control (MAC) address filtering, and Wired Equivalent Privacy (WEP) network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

  11. Finnish experiences of health monitoring: local, regional, and national data sources for policy evaluation

    Directory of Open Access Journals (Sweden)

    Katri Kilpeläinen

    2016-02-01

    Full Text Available Background: Finland has a long tradition of gathering information about the health and welfare of the adult population. Design: Surveys and administrative registers form the basis for national and local health monitoring in Finland. Results: Different data sources are used in Finland to develop key indicators, which can be used to evaluate how the national health policy targets have been met in different parts of the country and in different population subgroups. Progress has been shown in chronic disease risk factors, such as smoking reduction. However, some health policy targets have not been met. Socioeconomic health differences, for example, have remained large compared with other European countries. Conclusion: Although data availability for key health indicators is good in Finland, there is a need for wider and more comprehensive use of this information by political decision-makers and healthcare professionals.

  12. Effects of ionizing scrape-off layers on local recycling in Tore Supra pump limiter experiments

    International Nuclear Information System (INIS)

    Owen, L.W.; Hogan, J.T.; Klepper, C.C.; Mioduszewski, P.K.; Uckan, T.; Chatelier, M.; Loarer, T.

    1992-01-01

    A series of ohmic discharges with active pumping in the Tore Supra outboard pump limiter has been analyzed with the DEGAS neutrals transport code and an analysis scrape-off layer (SOL) plasma model. Pumping speed and plenum pressure measurements indicated 5--10 torr-L/s throughput with only modest effects on density (dN core /dt + source rate from ionization and dissociation of wall-desorbed molecules is seen to peak very near the radial position of the limiter throat. Consequently, a strong recycling vortex is created in the region of the limiter, with the ion flux amplified by factors of ∼2 at the outer limiter surfaces and >3 within the limiter throat. The calculations indicate that less than 30% of the pump throughput is due to first-generation ions from the core efflux, with the balance from local recycling in the strongly ionizing scrape-off layer

  13. Local Human Development in contexts of permanent crisis: Women’s experiences in the Western Sahara

    Directory of Open Access Journals (Sweden)

    María López Belloso

    2009-04-01

    Full Text Available Sahrawi women are active agents in the social dynamics of the refugee camps, in which they have developeda number of coping strategies to overcome the hardships of a deteriorating humanitarian situation. Since the outbreak of the con#ict and the forced settlement in Tindouf, Algeria, women have been responsible for the entire management of refugee camps, assuming leadership roles in many sectors of society.This paper highlights the Sahrawi women’s contribution to the process of local human development in a context of protracted refuge such as the one in the Western Sahara. In addition to the enlargement of the refugee population’s capacities in relation to material and physical assets, social and organizational abilities, and motivational strengths, one of the major achievements of Sahrawi women has been their own individual and collective process of empowerment within the camp life.

  14. Integration of foreign and local medical staff in a disaster area: the Honduras and El Salvador experiences.

    Science.gov (United States)

    Waisman, Yehezkel

    2003-06-01

    International medical aid after natural disasters may take various forms, ranging from self-sufficient military forces to single experts or specialists who function primarily as advisers. A model integrating foreign and local medical staff has not previously been reported. In response to the call for international aid by the Honduran and El Salvadorian governments in the wake of Hurricane Mitch in November 1998 and the San Salvador earthquake in January 2001, Israel sent medical supplies and 10 member teams of medical professionals to each country. The aim of the present paper is to describe the unique Israeli approach to providing healthcare in disaster areas by integrating foreign and local medical staff, and to discuss its advantages and disadvantages. The paper focuses on the experience of the two emergency medicine physicians on the team who were assigned to the Atlantida General Hospital in La Ceiba, Honduras. The same team in San Salvador subsequently applied the same approach.

  15. Combined effects of local habitat, anthropogenic stress, and dispersal on stream ecosystems: a mesocosm experiment.

    Science.gov (United States)

    Turunen, Jarno; Louhi, Pauliina; Mykrä, Heikki; Aroviita, Jukka; Putkonen, Emmi; Huusko, Ari; Muotka, Timo

    2018-06-06

    The effects of anthropogenic stressors on community structure and ecosystem functioning can be strongly influenced by local habitat structure and dispersal from source communities. Catchment land uses increase the input of fine sediments into stream channels, clogging the interstitial spaces of benthic habitats. Aquatic macrophytes enhance habitat heterogeneity and mediate important ecosystem functions, being thus a key component of habitat structure in many streams. Therefore, the recovery of macrophytes following in-stream habitat modification may be prerequisite for successful stream restoration. Restoration success is also affected by dispersal of organisms from the source community, with potentially strongest responses in relatively isolated headwater sites that receive limited amount of dispersing individuals. We used a factorial design in a set of stream mesocosms to study the independent and combined effects of an anthropogenic stressor (sand sedimentation), local habitat (macrophytes, i.e. moss transplants) and enhanced dispersal (two levels: high vs. low) on organic matter retention, algal accrual rate, leaf decomposition and macroinvertebrate community structure. Overall, all responses were simple additive effects with no interactions between treatments. Sand reduced algal accumulation, total invertebrate density and density of a few individual taxa. Mosses reduced algal accrual rate and algae-grazing invertebrates, but enhanced organic matter retention and detritus- and filter-feeders. Mosses also reduced macroinvertebrate diversity by increasing the dominance by a few taxa. Mosses also reduced leaf-mass loss, possibly because the organic matter retained by mosses provided an additional food source for leaf-shredding invertebrates and thus reduced shredder aggregation into leaf packs. The effect of mosses on macroinvertebrate communities and ecosystem functioning was distinct irrespective of the level of dispersal, suggesting strong environmental

  16. Evaporation and condensation at a liquid methanol surface

    Science.gov (United States)

    Matsumoto, Mitsuhiro; Yasuoka, Kenji; Kataoka, Yosuke

    1994-07-01

    The dynamics of evaporation and condensation at a flat liquid surface of methanol were studied under the liquidvapor equilibrium condition at room temperature with molecular dynamics computer simulation techniques. Analysis of molecular trajectories shows that the condensation coefficient is 89%. It suggests that only a tenth of incident vapor molecules are reflected at the liquid surface, contrary to a prediction of a classical transition state theory. To investigate the potential barrier of the evaporation-condensation process, a particle insertion method was applied and the local chemical potential near the surface was evaluated. The calculated chemical potential is constant in the whole region including the surface layer and no potential barrier is observed in the vincinity of the surface, which casts strong doubt on the explanation of a transition state theory.

  17. Conditioned random walks and interaction-driven condensation

    International Nuclear Information System (INIS)

    Szavits-Nossan, Juraj; Evans, Martin R; Majumdar, Satya N

    2017-01-01

    We consider a discrete-time continuous-space random walk under the constraints that the number of returns to the origin (local time) and the total area under the walk are fixed. We first compute the joint probability of an excursion having area a and returning to the origin for the first time after time τ . We then show how condensation occurs when the total area constraint is increased: an excursion containing a finite fraction of the area emerges. Finally we show how the phenomena generalises previously studied cases of condensation induced by several constraints and how it is related to interaction-driven condensation which allows us to explain the phenomenon in the framework of large deviation theory. (paper)

  18. Gauss Seidel-type methods for energy states of a multi-component Bose Einstein condensate

    Science.gov (United States)

    Chang, Shu-Ming; Lin, Wen-Wei; Shieh, Shih-Feng

    2005-01-01

    In this paper, we propose two iterative methods, a Jacobi-type iteration (JI) and a Gauss-Seidel-type iteration (GSI), for the computation of energy states of the time-independent vector Gross-Pitaevskii equation (VGPE) which describes a multi-component Bose-Einstein condensate (BEC). A discretization of the VGPE leads to a nonlinear algebraic eigenvalue problem (NAEP). We prove that the GSI method converges locally and linearly to a solution of the NAEP if and only if the associated minimized energy functional problem has a strictly local minimum. The GSI method can thus be used to compute ground states and positive bound states, as well as the corresponding energies of a multi-component BEC. Numerical experience shows that the GSI converges much faster than JI and converges globally within 10-20 steps.

  19. Investigations on the Steam Condensation in a Vertical Tube Geometry

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji-Hwan; Jerng, Dong-wook [Chung-Ang University, Seoul (Korea, Republic of)

    2016-10-15

    In case of accidents that threats containment integrity, such as Station Black Out (SBO), it is able to depressurize containment using exterior-surface condensation in presence of non-condensable gases, which is named as Passive Containment Cooling System (PCCS). It is very important to precisely predict heat removal capability PCCS, as it affects safety and economics. The effect of curvature is not yet experimentally and numerically studied. It is reported that the effect of curvature exists at single-phase condition, yet it is not studied that if it can applicable to two-phase condensation in presence of non-condensables. In this paper, various experimental data are collected to analyze if it is able to observe curvature effect. However, it is hard to analyze experimental data, as the geometry, experimental conditions and means of measurement differs. To check if the differences between experiments are curvature effect, each experiment is compared with CFD simulation result using a commercial CFD code, STAR-CCM+. In this paper, with correlations derived from prior studies, we found the existence of curvature effect under PCCS operating condition. However, it is unable to find out a clear curvature effect at experiment data as they scatter much. As a means of comparison reference between experiment, CFD code is used. From comparison between CFD and experiment, we could confirm the existence of curvature effect. However, measured heat transfer coefficients of Kawakubo’s experiment are relatively low, whereas Dehbi’s measurement data are relatively high. Also, considering that usage of eq. overly supplies steam to condensing shell region, heat transfer coefficients of Pan Tong’s measured relatively high, but not as much that of Dehbi’s. A further experimental identification is needed for evaluation. Currently, CFD code calculates the curvature effect. Overall trend versus air mass fraction is similar with average of experiment.

  20. COMMUNITY BASED TOURISM AND LOCAL EXPERIENCES. CASE STUDY OF THE INDIGENOUS COMMUNITY MARAVILLA, TENEJAPA, CHIAPAS

    Directory of Open Access Journals (Sweden)

    Julio César Sánchez Morales

    2014-01-01

    Full Text Available This article discusses the experiences of the residents of Ejido Las Nubes, municipality of Maravilla Tenejapa in an ecotourism project called Green Causes. The results show the no easy effort they make from years ago, with little relevance to the financial aspect, but strength in decision-making, from the organizational innovations in agency capacity for the permanence of the project and conservation of natural resources. Decisions on the project involve a position not only instrumental, but normative, with participatory and consensus. Nothing strange is that this process has generated social learning among This research was conducted from a qualitative and quantitative approach.

  1. Interplay between kaon condensation and hyperons in highly dense matter

    International Nuclear Information System (INIS)

    Muto, Takumi

    2008-01-01

    The possible coexistence and/or competition of kaon condensation with hyperons are investigated in hyperonic matter, where hyperons are mixed in the ground state of neutron-star matter. The formulation is based on the effective chiral Lagrangian for the kaon-baryon interaction and the nonrelativistic baryon-baryon interaction model. First, the onset condition of the s-wave kaon condensation realized from hyperonic matter is reexamined. It is shown that the usual assumption of the continuous phase transition is not always kept valid in the presence of the negatively charged hyperons (Σ - ). Second, the equation of state (EOS) of the kaon-condensed phase in hyperonic matter is discussed. In the case of the stronger kaon-baryon attractive interaction, it is shown that a local energy minimum with respect to the baryon number density appears as a result of considerable softening of the EOS due to both kaon condensation and hyperon mixing and recovering of the stiffness of the EOS at very high densities. This result implies a possible existence of self-bound objects with kaon condensates on any scale from an atomic nucleus to a neutron star

  2. THE FIRST EXPERIENCE OF USING LOCAL HYPERTHERMIA IN COMBINED MODALITY TREATMENT OF OPERABLE NON-SMALL CELL LUNG CANCER

    Directory of Open Access Journals (Sweden)

    A. Yu. Dobrodeev

    2015-01-01

    Full Text Available The paper presents the first experience in treating 5 patients with stage II–III non-small cell lung cancer using combined modality treatment including 40 Gy preoperative hyperfractionated radiotherapy with concurrent 2 cycles of paclitaxel/carboplatin chemotherapy and local hyperthermia (10 sessions followed by radical surgery. The overal response rate to preoperative treatment was 80 %. Chemotherapy was well tolerated and hyperthermia resulted no in adverse effects. All patients underwent surgery (4 lobectomies and 1 pneumonectomy. No complications were observed in the postoperative period. The follow-up period ranged from 6 to 20 months. No evidence of disease progression and radiation-induced damages were observed.

  3. Radiotherapy of locally advanced laryngeal cancer: the Gliwice Center of Oncology experience, 1990-1996

    International Nuclear Information System (INIS)

    Mucha-Malecka, A.; Skladowski, K.; Wygoda, A.; Sasiadek, W.; Tarnawski, R.

    2001-01-01

    The aim of the study was to assess the efficacy of radiotherapy alone in patients with locally advanced laryngeal cancer T3 - T4, and to establish the prognostic value of the size and the location of the extra laryngeal infiltrations and of emergency tracheostomy. 296 patients with advanced squamous cell cancer of the larynx were radically treated with radiotherapy alone in Center of Oncology in Gliwice between the years 1990 and 1996. There were 221 cases of supraglottic cancer (75%) and 75 of glottic cancer (25%). The stages were as follows: supraglottic cancer: T3 - 113 (51%), T4 - 108 (49%), glottic cancer: T3 - 69 (92%), T4 - 6 (8%). Positive neck nodes were found in 100 patients with supraglottic cancer (45%), and only in 11 patients with glottic cancer (15%). In cases of extra laryngeaI invasion (T4) the pyriform recess was involved in 33%, the base of tongue and valleculae glosso-epiglotticae in 30%, the hypopharyngeal wall in 9% of cases, while a massive involvement of the larynx, the pyriform recess and the base of the tongue was found in 6% of patients. Cartilage involvement was suspected in 22% of patients. Thirty six patients (12%) underwent emergency tracheostomy. Generally, the 3-year local control rate (LC) and disease free survival rate (DSF) were 46% and 41%, respectively. The probability of LC was similar in both supraglottic and glottic cancer: 44% and 47.5% respectively. The presence of involved neck nodes significantly decreased LC and DFS rates in both groups (about 20%). For stage T4 laryngeal cancer the LC rate was correlated with the location of the extra laryngeal infiltrations. Best prognosis was connected with the suspicion of cartilage infiltration - 56% of 3-year LC rate. The worst results were noted in cases of massive infiltrations spreading from larynx through the hypopharynx - 13.5% of 3-year LC rate. Emergency tracheostomy before radiotherapy was very significantly linked to poorer treatment results. The 3-year LC rate in

  4. Patient dosimetry and image quality in conventional diagnostic radiology. An experience from a local Serbian hospital

    International Nuclear Information System (INIS)

    Olivera Ciraj-Bjelac; Milojko Kovacevic; Dusko Kosutic; Milan Loncar; Dajana Veljkovic

    2007-01-01

    Complete test of publication follows. The optimization of image quality vs. patient dose ins an important task in medical imaging. Maximal validity of optimization has to be based on clinical images. Simultaneous measurement of patient dose levels and image quality assessment is used to investigate possibilities for dose reduction and maintain image quality. The survey was conducted in a local hospital performing more than 60000 images annually and representing typical Serbian practice. For four most frequent diagnostic procedures (seven projections) patient exposure was measured using kerma area product meter. Image quality was assessed by experienced radiologists using 'European Guidelines on Quality Criteria for Diagnostic Radiographic Images'. Following examination types were included into the survey: chest PA, chest LAT, pelvis AP, lumbar spine AP, lumbar spine LAT and LSJ, skull PA and skull LAT. Comparing actual radiographic technique with recommended technique in European Guidelines, modification of practice was proposed and implemented and image quality was re-assessed. At least 10 adult patients were followed for each projection, before and after corrective actions. Large dose saving without compromising diagnostic information were found for some examination types, showing that this simple method is very efficient dose reduction tool in conventional diagnostic radiology. Also, need for staff training and difficulties related to practical implementation of optimization methods in Serbia were discussed.

  5. A local area network for medical research; planning, realization and experience.

    Science.gov (United States)

    Schosser, R; Weiss, C; Messmer, K

    1991-01-01

    This report focuses on the planning and realization of an interdisciplinary local area network (LAN) for medical research at the University of Heidelberg. After a detailed requirements analysis, several networks were evaluated by means of a test installation, and a cost-performance analysis was carried out. At present, the LAN connects 45 (IBM-compatible) PCs, several heterogeneous mainframes (IBM, DEC and Siemens) and provides access to the public X.25 network and to wide-area networks for research (EARN, BITNET). The network supports application software that is frequently needed in medical research (word processing, statistics, graphics, literature databases and services, etc.). Compliance with existing "official" (e.g., IEEE 802.3) and "de facto" standards (e.g., PostScript) was considered to be extremely important for the selection of both hardware and software. Customized programs were developed to improve access control, user interface and on-line help. Wide acceptance of the LAN was achieved through extensive education and maintenance facilities, e.g., teaching courses, customized manuals and a hotline service. Since requirements of clinical routine differ substantially from medical research needs, two separate networks (with a gateway in between) are proposed as a solution to optimally satisfy the users' demands.

  6. Practical experience with a local verification system for containment and surveillance sensors

    International Nuclear Information System (INIS)

    Lauppe, W.D.; Richter, B.; Stein, G.

    1984-01-01

    With the growing number of nuclear facilities and a number of large commercial bulk handling facilities steadily coming into operation the International Atomic Energy Agency is faced with increasing requirements as to reducing its inspection efforts. One means of meeting these requirements will be to deploy facility based remote interrogation methods for its containment and surveillance instrumentation. Such a technical concept of remote interrogation was realized through the so-called LOVER system development, a local verification system for electronic safeguards seal systems. In the present investigations the application was extended to radiation monitoring by introducing an electronic interface between the electronic safeguards seal and the neutron detector electronics of a waste monitoring system. The paper discusses the safeguards motivation and background, the experimental setup of the safeguards system and the performance characteristics of this LOVER system. First conclusions can be drawn from the performance results with respect to the applicability in international safeguards. This comprises in particular the definition of design specifications for an integrated remote interrogation system for various types of containment and surveillance instruments and the specifications of safeguards applications employing such a system

  7. Contralateral breast dose from chest wall and breast irradiation: local experience

    International Nuclear Information System (INIS)

    Alzoubi, A.; Kandaiya, S.; Shukri, A.; Elsherbieny, E.

    2010-01-01

    Full text: Second cancer induction in the contralateral breast (CB) is an issue of some concern in breast radiotherapy especially for women under the age of 45 years at the time of treatment. The CB dose from 2-field and 3-field techniques in post-mastectomy chest wall irradiations in an anthropomorphic phantom as well as in patients were measured using thermoluminescent dosimeters (TLDs) at the local radiotherapy center. Breast and chest wall radiotherapy treatments were planned conformally (3D-CRT) and delivered using 6-MV photons. The measured CB dose at the surface fell sharply with distance from the field edge. However, the average ratio of the measured to the calculated CB dose using the pencil beam algorithm at the surface was approximately 53%. The mean and median measured internal dose at the posterior border of CB in a phantom was 5.47 ± 0.22 c G y and 5.44 c G y, respectively. The internal CB dose was relatively independent of depth. In the present study the internal CB dose is 2.1-4.1 % of the prescribed dose which is comparable to the values reported by other authors.

  8. Further experience with the local lymph node assay using standard radioactive and nonradioactive cell count measurements.

    Science.gov (United States)

    Kolle, Susanne N; Basketter, David; Schrage, Arnhild; Gamer, Armin O; van Ravenzwaay, Bennard; Landsiedel, Robert

    2012-08-01

    In a previous study, the predictive capacity of a modified local lymph node assay (LLNA) based on cell counts, the LNCC, was demonstrated to be closely similar to that of the original assay. In addition, a range of substances, including some technical/commercial materials and a range of agrochemical formulations (n = 180) have also been assessed in both methods in parallel. The results in the LNCC and LLNA were generally consistent, with 86% yielding an identical classification outcome. Discordant results were associated with borderline data and were evenly distributed between the two methods. Potency information derived from each method also demonstrated good consistency (n = 101), with 93% of predictions being close. Skin irritation was observed only infrequently and was most commonly associated with positive results; it was not associated with the discordant results. Where different vehicles were used with the same test material, the effect on sensitizing activity was modest, consistent with historical data. Analysis of positive control data indicated that the LNCC and LLNA displayed similar levels of biological variation. When taken in combination with the previously published results on LLNA Performance Standard chemicals, it is concluded that the LNCC provides a viable non-radioactive alternative to the LLNA for the assessment of substances, including potency predictions, as well as for the evaluation of preparations. Copyright © 2012 John Wiley & Sons, Ltd.

  9. Local Control of Perivascular Malignant Liver Lesions Using Percutaneous Irreversible Electroporation: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Eller, Achim, E-mail: Achim.Eller@uk-erlangen.de; Schmid, Axel, E-mail: axel.schmid@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany); Schmidt, Joachim, E-mail: joachim.schmidt@kfa.imed.uni-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Anesthesiology (Germany); May, Matthias, E-mail: matthias.may@uk-erlangen.de; Brand, Michael, E-mail: michael.brand@uk-erlangen.de; Saake, Marc, E-mail: marc.saake@uk-erlangen.de; Uder, Michael, E-mail: michael.uder@uk-erlangen.de; Lell, Michael, E-mail: michael.lell@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany)

    2015-02-15

    PurposeThis study was designed to assess efficacy and safety in the treatment of perivascular malignant liver lesions using percutaneous, computed tomography (CT)-guided irreversible electroporation (IRE).MethodsFourteen patients (mean age 58 ± 11 years) with 18 malignant liver lesions were consecutively enrolled in this study. IRE was performed in patients not eligible for surgery and lesions abutting large vessels or bile ducts. Follow-up exams were performed using multislice-CT (MS-CT) or MRI.ResultsMedium lesion diameter was 20 ± 5 mm. Ten of 14 (71 %) were successfully treated with no local recurrence to date (mean follow-up 388 ± 160 days). One case left initial tumor control unclear and additional RFA was performed 4 weeks after IRE. Complications occurred in 4 of 14 (29 %) cases. In one case, intervention was terminated and abdominal bleeding required laparotomy. In two cases, a postinterventional hematothorax required intervention. In another case, abdominal bleeding could be managed conservatively. No complications related to the bile ducts occurred.ConclusionsPercutaneous IRE seems to be effective in perivascular lesions but is associated with a higher complication rate compared with thermoablative techniques.

  10. Concurrent chemoradiotherapy with gemcitabine plus regional hyperthermia for locally advanced pancreatic carcinoma. Initial experience

    International Nuclear Information System (INIS)

    Ohguri, Takayuki; Imada, Hajime; Yahara, Katsuya; Morioka, Tomoaki; Nakano, Keita; Korogi, Yukunori; Narisada, Hiroyuki

    2008-01-01

    The aim of this study was to evaluate the efficacy and toxicity of concurrent chemoradiotherapy (CRT) with gemcitabine plus regional hyperthermia (HT) for locally advanced pancreatic carcinoma (LAPC). A total of 29 patients with LAPC treated with concurrent CRT using gemcitabine were retrospectively analyzed. Radiotherapy was administered with a median total dose of 61.2 Gy. Of the 29 patients, 20 (69%) also underwent regional HT during CRT (CRHT group). The remaining 9 patients did not receive regional HT (CRT group) because of a common bile duct stent placement, patient refusal, older age, or obesity. The efficacy and toxicity of the treatments and the predictors of good outcome were evaluated. The median disease progression-free and overall survival times were significantly better for the CRHT group than for the CRT group (8.8 vs. 4.9 months, P=0.02, and 18.6 vs. 9.6 months, P=0.01), respectively. Grade 3-4 hematological toxicities for the CRHT group were detected in eight patients (40%) and grade 3 nonhematologic toxicity in one (diarrhea). Concurrent CRT using gemcitabine with regional HT may be a feasible and promising regimen for LAPC, and the results justified further evaluation in a large number of patients to confirm its definite benefit. (author)

  11. ADAPTAÇÃO COMENTADA DE UNIDADE DIDÁTICA AO CONTEXTO LOCAL: LEARNING EXPERIENCES

    Directory of Open Access Journals (Sweden)

    Raquel Salcedo Gomes

    2015-09-01

    Full Text Available O objetivo do presente trabalho é apresentar e discutir o processo de elaboração de uma unidade didática para a 3a série do Ensino Médio a partir da adaptação do livro didático ao contexto local da turma e da escola. Para tanto, articula-se uma reflexão sobre as orientações curriculares para o Ensino Médio brasileiro e os papéis do livro didático nesse processo, atribuindo-se a ele uma função mediadora advinda de uma perspectiva sociocultural de educação, ensino e aprendizagem. A discussão aponta para a necessidade de edição, adaptação e autoria docente na preparação de unidades didáticas e para seu aspecto de inacabamento, visto que a elaboração de materiais didáticos marca o ponto de partida do fazer docente, não sua conclusão. Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial 4.0 Internacional.

  12. Effects of ionizing scrape-off layers on local recycling in Tore Supra pump limiter experiments

    International Nuclear Information System (INIS)

    Chatelier, M.; Loarer, T.

    1992-01-01

    A series of ohmic discharges with active pumping in the Tore Supra outboard pump limiter has been analyzed with the DEGAS neutrals transport code and an analytic scrape-off layer (SOL) plasma model. Pumping speed and plenum pressure measurements indicated 5-10 torr.L/s throughput with only modest effects on density. A model is developed in which large exhaust fluxes, with little attendant effect on core plasma density, are explained in terms of SOL ionization of recycled and wall-desorbed neutrals. Particle balance with active pumping and constant line density requires that the wall return flux exceed the incident flux by approximately the pump throughput in the absence of external fueling. The radial profile of the H + source rate from ionization and dissociation of wall-desorbed molecules is seen to peak very near the radial position of the limiter throat. Consequently, a strong recycling vortex is created in the region of the limiter, with the ion flux amplified by factors of 2 at the outer limiter surfaces and > 3 within the limiter throat. The calculations indicate that less than 30% of the pump throughput is due to first-generation ions from the core efflux, with the balance from local recycling in the strongly ionizing SOL

  13. EMC3-EIRENE modeling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

    Energy Technology Data Exchange (ETDEWEB)

    Lore, J.D., E-mail: lorejd@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Reinke, M.L. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); LaBombard, B. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Lipschultz, B. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Churchill, R.M. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Pitts, R.A. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Feng, Y. [Max Planck Institute for Plasma Physics, Greifswald (Germany)

    2015-08-15

    Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ∼50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modeling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target.

  14. Condensation induced water hammer in steam generators

    International Nuclear Information System (INIS)

    Jones, O.C. Jr.; Saha, P.; Wu, B.J.C.; Ginsberg, T.

    1979-06-01

    The case of condensation induced water hammer in nuclear steam generators is summarized, including both feed ring-type and economizer-type geometries. A slug impact model is described and used to demonstrate the parametric dependence of the impact pressures on heat transfer rates, initial pressures, and relative initial slug and void lengths. The results of the parametric study are related also to the economizer geometry and a suggested alternative model is presented. The importance of concerns regarding attenuation of shocks in two-phase media is delineated, and a simple experiment is described which was used to determine negligible attenuation within the accuracy of the experiment for void fractions up to over 30% in bubbly and slug flows

  15. Coherence and chaos in condensed matter

    International Nuclear Information System (INIS)

    Bishop, A.R.

    1989-01-01

    This paper discusses the following topics: nonlinearity in condensed matter; coherence and chaos in spatially extended condensed matter systems; nonlinearity and magnetism; and solitons and conducting polymers. 52 refs., 7 figs

  16. Some concepts in condensed phase chemical kinetics

    International Nuclear Information System (INIS)

    Adelman, S.A.

    1986-01-01

    Some concepts in condensed phase chemical kinetics which have emerged from a recent rigorous statistical mechanical treatment of condensed phase chemical reaction dynamics (S.A. Adelman, Adv. Chem. Phys.53:61 (1983)) are discussed in simple physical terms

  17. Local experience on radionuclide myocardial imaging in the Philippines at the Philippine Heart Center for Asia

    International Nuclear Information System (INIS)

    Villacorta, E.V.

    1977-01-01

    The Nuclear Medicine Department of the Philippine Heart Center has introduced the detection of coronary heart disease through myocardiac perfusion imaging. The cardiovascular procedures are availed of free-of-charge to registered PHCA patients excepting for the costly TI-201 imaging. In summary, coronary perfusion in imaging should be an integral part of coronary arteriography. Barring the expensive cost of TI-120, myocardial perfusion imaging is ideal for detection of coronary heart disease. Experience shows better sensitivity of TI-201 than exercise ECG for detection of ischemia. Another non-invasive procedure for the detection of acute infarction is the radionuclide imaging using a bone radiopharmaceutical Tc99m prophosphate. In conclusion, acute infarct imaging is a valuable adjunct to ECG and enzyme studies. (RTD)

  18. Heat and mass transfer prediction of binary refrigerant mixtures condensing in a horizontal microfin tube

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Shigeru; Yu, Jian; Ishibashi, Akira

    1999-07-01

    In the face of the phase-out of HCFC22 for its effect on globe environment, the alternative refrigerant has been paid attention in the refrigeration and heat pump industry. In the present stage, it is found that any pure refrigerant is not a good substitute of HCFC22 for the system in use. The authors have to use binary or ternary refrigerant mixtures as the substitute to meet industrial requirement. But until now, although the heat transfer characteristics of the refrigerant mixtures can be measured in experiments and predicted in some degree, the mass transfer characteristics in condensation process, which is a main part in most systems, can not be clarified by both experimental and theoretical methods. In the present study a non-equilibrium model for condensation of binary refrigerant mixtures inside a horizontal microfin tube is proposed. In this model it is assumed that the phase equilibrium is only established at the vapor-liquid interface, while the bulk vapor and the bulk liquid are in non-equilibrium in the same cross section. The mass transfer characteristic in vapor core is obtained from the analogy between mass and momentum transfer. In the liquid layer, the mass fraction distribution is neglected, but the mass transfer coefficient is treated as infinite that can keep a finite value for the mass transfer rate in liquid phase. From the calculation results compared with the experimental ones for the condensation of HFC134a/HCFC123 and HCFC22/CFC114 mixtures, it is found that the calculated heat flux distribution along the tube axis is in good agreement with that of experiment, and the calculated values of condensing length agree well with the experimental ones. Using the present model, the local mass faction distribution, the diffusion mass transfer rate and the mass transfer characteristics in both vapor and liquid phase are demonstrated. From these results, the effect of mass transfer resistance on condensation heat transfer characteristics for binary

  19. Adjuvant chemotherapy for locally advanced urothelial carcinoma: an overview of the USC experience.

    Science.gov (United States)

    Dorff, Tanya B; Tsao-Wei, Denice; Miranda, Gus; Skinner, Donald G; Stein, John P; Quinn, David I

    2009-02-01

    To describe the tolerability of two chemotherapy regimens, gemcitabine and cisplatin (GC) and methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) for adjuvant treatment of patients with locally advanced urothelial cancer after radical cystectomy. The USC Department of Urology bladder cancer database was searched for subjects who received adjuvant chemotherapy following cystectomy for transitional cell carcinoma with extravesical and/or lymph node involvement, yielding 187 cases. Clinical details regarding toxicity, number of cycles administered, and cancer outcome were analyzed. The majority of subjects had lymph node involvement (70%). Sixty-eight percent of subjects received MVAC and 32% received GC, the latter regimen was predominant after 2000. Fifty-six percent of subjects received all four planned cycles (51% GC and 58% MVAC). With a median follow-up of 11.2 years (range 1.9-19.6), 96 patients (51%) have suffered a relapse, with no significant difference between chemotherapy regimens. Median time to recurrence for the population was 3.7 years and median overall survival is 4.6 years (3.0-9.3). The median time from recurrence to death was 6.7 months and was not significantly different between MVAC and GC. Both MVAC and GC are tolerated after cystectomy for advanced urothelial carcinoma. A significant proportion of high-risk patients survive, free of disease, beyond 10 years. At recurrence, patients previously treated with adjuvant chemotherapy have a survival that appears much shorter than patients who develop metastases in the absence of this exposure, suggesting resistance to salvage chemotherapy.

  20. Chest radiographic appearances in adult inpatients admitted with swine flu infection: local experience in Melbourne

    International Nuclear Information System (INIS)

    Pirakalathanan, Janu; Lau, Kenneth K.; Joosten, Simon A.

    2013-01-01

    The influenza A virus (H1N1) pandemic began in Mexico in March 2009. As of July 2009, there were 5298 reported cases in Australia including 10 deaths. The aim of this review is to demonstrate the local chest radiographic findings in adult inpatients with proven H1N1, to assess the radiological disease progression and resolution, and to evaluate whether the severity of chest X-rays findings had a bearing on the length of admission and need for intensive care admission. Eleven H1N1 patients (5 males and 6 females, mean age of 36), presenting with cough (64%), fever (55%) and shortness of breath (55%), were admitted to our hospital between 13 August and 1 November 2010. Details of radiographic features, risk factors, clinical course including length of stay, doubling time of consolidation and time for 50% resolution of consolidation were recorded and analysed. Seventy-three per cent of our patients presented with bilateral mid and/or lower zone alveolar consolidation. One patient with underlying cystic fibrosis had only bilateral upper zone consolidation. No pleural effusion, lymphadenopathy or cardiomegaly was noted on any of the plain chest radiographs. The mean doubling time of consolidation was 1.5 days. The mean time for 50% resolution of consolidation after antiviral treatment was 10.5 days. The average length of stay in hospital was 22 days. Ninety-one per cent of our patients required intensive-care unit admission with 50% of those requiring intubation. Rapid progression of bilateral mid and lower zone air-space opacities in relatively young unwell patients, with lack of pleural effusion, pericardial effusion or lymphadenopathy on plain radiographs, should raise the clinical suspicion of H1N1 infection. Patients requiring hospital admission usually show slow clinical and radiological improvement, and require prolonged hospital stays.

  1. Experience with local lymph node assay performance standards using standard radioactivity and nonradioactive cell count measurements.

    Science.gov (United States)

    Basketter, David; Kolle, Susanne N; Schrage, Arnhild; Honarvar, Naveed; Gamer, Armin O; van Ravenzwaay, Bennard; Landsiedel, Robert

    2012-08-01

    The local lymph node assay (LLNA) is the preferred test for identification of skin-sensitizing substances by measuring radioactive thymidine incorporation into the lymph node. To facilitate acceptance of nonradioactive variants, validation authorities have published harmonized minimum performance standards (PS) that the alternative endpoint assay must meet. In the present work, these standards were applied to a variant of the LLNA based on lymph node cell counts (LNCC) run in parallel as a control with the standard LLNA with radioactivity measurements, with threshold concentrations (EC3) being determined for the sensitizers. Of the 22 PS chemicals tested in this study, 21 yielded the same results from standard radioactivity and cell count measurements; only 2-mercaptobenzothiazole was positive by LLNA but negative by LNCC. Of the 16 PS positives, 15 were positive by LLNA and 14 by LNCC; methylmethacrylate was not identified as sensitizer by either of the measurements. Two of the six PS negatives tested negative in our study by both LLNA and LNCC. Of the four PS negatives which were positive in our study, chlorobenzene and methyl salicylate were tested at higher concentrations than the published PS, whereas the corresponding concentrations resulted in consistent negative results. Methylmethacrylate and nickel chloride tested positive within the concentration range used for the published PS. The results indicate cell counts and radioactive measurements are in good accordance within the same LLNA using the 22 PS test substances. Comparisons with the published PS results may, however, require balanced analysis rather than a simple checklist approach. Copyright © 2011 John Wiley & Sons, Ltd.

  2. Experiences with local power production at the end-user (case studies)

    International Nuclear Information System (INIS)

    Morch, Andrei Z.; Grinden, Bjoern; Fleten, Stein-Erik; Maribu, Karl Magnus; Johansen, Boerre; Vanebo, Torstein; Berner, Monica; Stang, Jacob; Naesje, Paal

    2004-12-01

    This report describes the results of case studies performed as part of the project 'Local power production at the end-user'. It was found that the construction of a power plant, even a small one, is not an easy task. It is important to exploit the resources optimally and to allow for many income and cost elements in calculating the profitability. It may therefore be worth while to consult qualified assistance at an early stage during the planning of such construction projects. It is also found that there are clear scale effects in the development of small power plants, that is, the relative costs (NOK/kWh) are larger for small plants than for bigger ones. This is true of both investment costs and operation costs. This will affect the profitability. Of 16 plants, there is enough data for analysing 15, although estimates must be used instead of real data where the latter is missing. For eight of the 15, the net present value is positive at a power price of 25 oere/kWh, 6% discount rate and 15-20 years lifetime. For the other plants it will be more economical to wait until the market price of power rises. The price that is necessary to make these plants profitable varies from 32 to 45 oere/kWh. Basically it is assumed that the developer of small power plants (up to 10 MW) wants to produce as much energy (kWh) as possible from the plant, both to cover his own consumption and to sell surplus energy to the power market. However, there is an economically interesting market for power (kW), in which the producer (over 25 MW) is paid for being ready to start production on short notice

  3. Local experience in cervical cancer imaging: Comparison in tumour assessment between TRUS and MRI.

    Science.gov (United States)

    Ordeanu, Claudia; Pop, Diana Cristina; Badea, Radu; Csutak, Csaba; Todor, Nicolae; Ordeanu, Calin; Kerekes, Reka; Coza, Ovidiu; Nagy, Viorica; Achimas-Cadariu, Patriciu; Irimie, Alexandru

    2015-01-01

    The aim of study was to analyze the accuracy of TRUS (transrectal ultrasound) vs. MRI (magnetic resonance imaging) and clinical gynecological examination estimation in the evaluation of tumor dimensions. The patients inclusion criterion included primarily pathologically squamous cell carcinoma, but excluded were patients who had not undergone BT (brachytherapy) and treated with palliative intent. We offer two types of treatment for locally advanced cervical cancer: (a) radiochemotherapy followed by surgery and (b) exclusive radiochemotherapy. Imaging tests follow the presence of tumor and tumor size (width and thickness). Each examination was performed by a different physician who had no knowledge of the others' findings. All patients underwent MRI prior to EBRT (external beam radiation therapy) while 18 of them also at the time of the first brachytherapy application. For the analysis we used the r-Pearson correlation coefficient. In 2013, 26 patients with cervical cancer were included. A total of 44 gynecological examinations were performed, 44 MRIs and 18 TRUSs. For the comparisons prior to EBRT the correlation coefficient between TRUS vs. MRI was r = 0.79 for AP and r = 0.83 for LL, for GYN vs. MRI was r = 0.6 for AP and r = 0.75 for LL. Prior to BT for GYN vs. MRI, r values were 0.60 and 0.63 for AP and LL, respectively; for GYN vs. TRUS, r values were 0.56 and 0.78 for AP and LL, respectively. A high correlation between the three examinations was obtained. As such, TRUS can be considered a suitable method in the evaluation of tumor dimensions.

  4. Initial Thomson Scattering Survey of Local Helicity Injection and Ohmic Plasmas at the Pegasus Toroidal Experiment

    Science.gov (United States)

    Schlossberg, D. J.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Winz, G. R.

    2014-10-01

    A multipoint Thomson scattering diagnostic has recently been installed on the Pegasus ST. The system utilizes a frequency-doubled Nd:YAG laser (λ0 ~ 532 nm), spectrometers with volume phase holographic gratings, and a gated, intensified CCD camera. It provides measurements of Te and ne at 8 spatial locations for each spectrometer once per discharge. A new multiple aperture and beam dump system has been implemented to mitigate interference from stray light. This system has provided initial measurements in the core region of plasmas initiated by local helicity injection (LHI), as well as conventional Ohmic L- and H-mode discharges. Multi-shot averages of low-density (ne ~ 3 ×1018 m-3) , Ip ~ 0 . 1 MA LHI discharges show central Te ~ 75 eV at the end of the helicity injection phase. Ip ~ 0 . 13 MA Ohmic plasmas at moderate densities (ne ~ 2 ×1019 m-3) have core Te ~ 150 eV in L-mode. Generally, these plasmas do not reach transport equilibrium in the short 25 ms pulse length available. After an L-H transition, strong spectral broadening indicates increasing Te, to values above the range of the present spectrometer system with a high-dispersion VPH grating. Near-term system upgrades will focus on deploying a second spectrometer, with a lower-dispersion grating capable of measuring the 0.1-1.0 keV range. The second spectrometer system will also increase the available number of spatial channels, enabling study of H-mode pedestal structure. Work supported by US DOE Grant DE-FG02-96ER54375.

  5. Pion condensation and neutron star dynamics

    International Nuclear Information System (INIS)

    Kaempfer, B.

    1983-01-01

    The question of formation of pion condensate via a phase transition in nuclear matter, especially in the core of neutron stars is reviewed. The possible mechanisms and the theoretical restrictions of pion condensation are summarized. The effects of ultradense equation of state and density jumps on the possible condensation phase transition are investigated. The possibilities of observation of condensation process are described. (D.Gy.)

  6. Gauge field condensation in geometric quantum chromodynamics

    International Nuclear Information System (INIS)

    Guendelman, E.I.

    1991-09-01

    In odd number of dimensions, it is possible to construct general covariant gauge theories, where the metric is not an independent variable, but local function of the gauge fields. Starting from standardly defined gauge theory, upon functional integration of some variables, we could end up with such moodels. For models with SU(2) and SU(3) symmetry in three dimensions, gauge field condensation take place in the vacuum, which is nevertheless homogeneous and isotropic up to a gauge transformation, provided the space is flat. Introducing Higgs fields that spontaneously break the gauge symmetry, we get a breakdown of the homogenity and isotropy of the vacuum. Finally, we discuss how some of this ideas can be generalized to four and other even dimensions. (author)

  7. Statistical mechanics and applications in condensed matter

    CERN Document Server

    Di Castro, Carlo

    2015-01-01

    This innovative and modular textbook combines classical topics in thermodynamics, statistical mechanics and many-body theory with the latest developments in condensed matter physics research. Written by internationally renowned experts and logically structured to cater for undergraduate and postgraduate students and researchers, it covers the underlying theoretical principles and includes numerous problems and worked examples to put this knowledge into practice. Three main streams provide a framework for the book; beginning with thermodynamics and classical statistical mechanics, including mean field approximation, fluctuations and the renormalization group approach to critical phenomena. The authors then examine quantum statistical mechanics, covering key topics such as normal Fermi and Luttinger liquids, superfluidity and superconductivity. Finally, they explore classical and quantum kinetics, Anderson localization and quantum interference, and disordered Fermi liquids. Unique in providing a bridge between ...

  8. Condensed matter physics with radioactive ion beams

    International Nuclear Information System (INIS)

    Haas, H.

    1996-01-01

    An overview of the present uses of radioactive ion beams from ISOLDE for condensed matter research is presented. As simple examples of such work, tracer studies of diffusion processes with radioisotopes and blocking/channeling measurements of emitted particles for lattice location are discussed. Especially the application of nuclear hyperfine interaction techniques such as PAC or Moessbauer spectroscopy has become a powerful tool to study local electronic and structural properties at impurities. Recently, interesting information on impurity properties in semiconductors has been obtained using all these methods. The extreme sensitivity of nuclear techniques makes them also well suited for investigations of surfaces, interfaces, and biomolecules. Some ideas for future uses of high energy radioactive ion beams beyond the scope of the present projects are outlined: the study of diffusion in highly immiscible systems by deep implantation, nuclear polarization with the tilted-foil technique, and transmutation doping of wide-bandgap semiconductors. (orig.)

  9. Managed Aquifer Recharge: from Local Research and Experiences to Regional Aquifer Storage and Recovery

    Science.gov (United States)

    Hendriks, D.; Faneca, M.; Oude Essink, G.; van Baaren, E.; Stuurman, R.; Delsman, J. R.; van Kempen, C.; de Louw, P.

    2016-12-01

    Many areas in the world experience periodic water shortages due to meteorological drought, salt water intrusion or over-exploitation of the water resources. Recently, it was established that the depletion of aquifers in many areas of the world is in an advanced state (Gleeson et al, 2012). This poses enormous challenges as 2.5 billion people and many companies depend on groundwater now and in the future (UN, 2015; ESG, 2016). A solution to increase robustness of water systems and prevent water shortage is subsurface storage of water during wet periods using Managed Aquifer Research (MAR). In addition to mitigation of water shortage, MAR can also reduce the occurrence and degree of flooding. Here, we present an overview of Deltares MAR expertise and available tools for up-scaling MAR. Deltares has experience with both research and implementation of MAR in different parts of the world under various hydro(geo)logical, climatic and socio-economic conditions. Various MAR techniques were assessed/tested in coastal areas of the Netherlands, Spain, New York, New Orleans and in Bangladesh. In some of these areas specific groundwater shortage related issues occur, such as salt water intrusion or subsidence. In Singapore, monitoring campaigns and modeling were done to design MAR by infiltration of water in over-exploited aquifers. In Abu Dhabi, geophysical methods were used to detect the optimal conditions for MAR systems. To effectively increase the robustness of groundwater systems up-scaling of MAR is required. For this purpose, Deltares developed tools that provide insight in the potential demand, possibilities and effectiveness of MAR at larger scales. The Quick scan tool for Fresh Groundwater Buffering provides insight on regional to national scale and is based on GIS-information of water demand, water resources, and subsurface properties. This quick scan tool has been applied for Mozambique, Kenya, India and Bangladesh. The Fresh Water Optimizer assesses the

  10. Novel insights into nanopore deformation caused by capillary condensation.

    Science.gov (United States)

    Günther, Gerrit; Prass, Johannes; Paris, Oskar; Schoen, Martin

    2008-08-22

    By means of in situ small-angle x-ray diffraction experiments and semi-grand-canonical ensemble Monte Carlo simulations we demonstrate that sorption and condensation of a fluid confined within nanopores is capable of deforming the pore walls. At low pressures the pore is widened due to a repulsive interaction caused by collisions of the fluid molecules with the walls. At capillary condensation the pores contract abruptly on account of attractive fluid-wall interactions whereas for larger pressures they expand again. These features cannot solely be accounted for by effects related to pore-wall curvature but have to be attributed to fluid-wall dispersion forces instead.

  11. Capillary condensation, invasion percolation, hysteresis, and discrete memory

    International Nuclear Information System (INIS)

    Guyer, R.A.; McCall, K.R.

    1996-01-01

    A model of the capillary condensation process, i.e., of adsorption-desorption isotherms, having only pore-pore interactions is constructed. The model yields (1) hysteretic isotherms, (2) invasion percolation on desorption, and (3) hysteresis with discrete memory for interior chemical potential loops. All of these features are seen in experiment. The model is compared to a model with no pore-pore interactions (the Preisach model) and to a related model of interacting pore systems (the random field Ising model). The capillary condensation model differs from both. copyright 1996 The American Physical Society

  12. Charge Screening in a Charged Condensate

    International Nuclear Information System (INIS)

    Gabadadze, Gregory; Rosen, Rachel A.

    2009-01-01

    We consider a highly dense system of helium-4 nuclei and electrons in which the helium-4 nuclei have condensed. We present the condensation mechanism in the framework of low energy effective field theory and discuss the screening of electric charge in the condensate.

  13. Some issues in the ghost condensation scenario

    International Nuclear Information System (INIS)

    Anisimov, A.

    2004-01-01

    In the recently proposed 'ghost condensation' scenario a model of consistent infrared modification of gravity was suggested. We first review the basic ideas of this scenario. We discuss various phenomenological aspects of the ghost condensation, such as stability of the condensate, bounds on the UV cut-off scale of the corresponding effective field theory and other issues. (author)

  14. Computations for a condenser. Experimental results

    International Nuclear Information System (INIS)

    Walden, Jean.

    1975-01-01

    Computations for condensers are presented with experimental results. The computations are concerned with the steam flux at the condenser input, and inside the tube bundle. Experimental results are given for the flux inside the condenser sleeve and the flow passing through the tube bundle [fr

  15. CO2 capture by Condensed Rotational Separation

    NARCIS (Netherlands)

    Benthum, van R.J.; Kemenade, van H.P.; Brouwers, J.J.H.; Golombok, M.

    2010-01-01

    Condensed Rotational Separation (CRS) technology is a patented method to upgrade gas mixtures. A novel application is thecapture of CO2 from coal-combustion fired power stations: Condensed Contaminant Centrifugal Separation in Coal Combustion(C5sep). CRS involves partial condensation of a gas

  16. Local geology determines responses of stream producers and fungal decomposers to nutrient enrichment: A field experiment.

    Science.gov (United States)

    Mykrä, Heikki; Sarremejane, Romain; Laamanen, Tiina; Karjalainen, Satu Maaria; Markkola, Annamari; Lehtinen, Sirkku; Lehosmaa, Kaisa; Muotka, Timo

    2018-04-16

    We examined how short-term (19 days) nutrient enrichment influences stream fungal and diatom communities, and rates of leaf decomposition and algal biomass accrual. We conducted a field experiment using slow-releasing nutrient pellets to increase nitrate (NO 3 -N) and phosphate (PO 4 -P) concentrations in a riffle section of six naturally acidic (naturally low pH due to catchment geology) and six circumneutral streams. Nutrient enrichment increased microbial decomposition rate on average by 14%, but the effect was significant only in naturally acidic streams. Nutrient enrichment also decreased richness and increased compositional variability of fungal communities in naturally acidic streams. Algal biomass increased in both stream types, but algal growth was overall very low. Diatom richness increased in response to nutrient addition by, but only in circumneutral streams. Our results suggest that primary producers and decomposers are differentially affected by nutrient enrichment and that their responses to excess nutrients are context dependent, with a potentially stronger response of detrital processes and fungal communities in naturally acidic streams than in less selective environments.

  17. WWER-440 local power peaking experiment with/without Hf inserts in the LR-0 reactor

    International Nuclear Information System (INIS)

    Josek, R.; Hudec, F.; Rypar, V.

    2006-01-01

    One of the known issues of the WWER-440 reactors is the control rod coupler induced power peaking in the neighbouring fuel assemblies. The effect has been discovered some years ago and is believed to be the cause of several fuel failures during operation in WWER-440 reactors. The effect itself is due to over-moderation and small absorption in the region of control rod coupler, leading to increase in thermal neutron flux and hence to power flare-up in the neighbouring fuel pins. The fuel vendor tackled the problem by attaching hafnium inserts on the inside of the control assembly box. The experiment performed in the LR-0 reactor was focused on the axial and radial power profiles in the vicinity of the control assembly with and without the hafnium inserts. The results of measurements with zero boron concentration are presented. The hafnium insert causes a decrease in peaking factor of about 30% in selected pins close to the control assembly. The measurements are compared with calculations performed with the MCNP-4C code. The compared variables are: the axial fission density distributions; peking factors and peaking factor decrease due to Hf insert. The MCNP results are accurate with respect to the experimental results. A series of benchmarks is being prepared on the basis of these measurements

  18. Biological distribution of reactor produced 18F-FDG. Local experience

    International Nuclear Information System (INIS)

    Sierralta, M.P.; Massardo, T.; Gil, M.C.; Chandia, M.; Godoy, N.; Troncoso, F.; Jofre, M.J.

    2002-01-01

    differences of SA in many organs, between the authors and between them and our results, except at the heart. Conclusion: No statistically significant differences in the critical organ in study (heart) were found. Hence, local reactor produced 18F-FDG is a useful radiotracer in cardiac cellular metabolism assessment

  19. Biological distribution of reactor produced 18F-FDG. Local experience

    Energy Technology Data Exchange (ETDEWEB)

    Sierralta, M P [University of Chile Clinical Hospital Nuclear Medicine Centre, Santiago (Chile); Military Hospital Nuclear Medicine Department, Santiago (Chile); Massardo, T [University of Chile Clinical Hospital Nuclear Medicine Centre, Santiago (Chile); Gil, M C [CGM Nuclear, Santiago (Chile); Chandia, M; Godoy, N; Troncoso, F [CCHEN, CEN La Reina, Santiago (Chile); Jofre, M J [Military Hospital Nuclear Medicine Department, Santiago (Chile)

    2002-09-01

    differences of SA in many organs, between the authors and between them and our results, except at the heart. Conclusion: No statistically significant differences in the critical organ in study (heart) were found. Hence, local reactor produced 18F-FDG is a useful radiotracer in cardiac cellular metabolism assessment.

  20. Experimental and computational analysis of steam condensation in the presence of air and helium

    International Nuclear Information System (INIS)

    Bucci, M.

    2010-01-01

    Among the different phenomena expected to occur within nuclear reactor containments during a postulated loss of coolant accident, condensation on containment walls plays a major role, since it represents an important heat sink for evacuating the energy released by the discharge of the primary water. Nevertheless, condensation strongly affects other relevant phenomena, like containment atmosphere mixing, that influences the distribution of non-condensable gases hypothetically delivered in severe accident conditions. In this scenario, the role of condensation is not obvious, since it can locally aid the hydrogen produced by the oxidation of the core claddings to concentrate and reach flammability limits, providing a dangerous effect instead of a positive one. The understanding of condensation in the presence of air and hydrogen is therefore a fundamental task for the safety analyses of reactor containments. This research has been carried out with the aim to contribute to the understanding of these phenomena. A double strategy has been adopted, including complementary experimental and computational activities. Novel data have been made available by the CONAN facility, investigating the effects induced by light non-condensable gases in experimental configurations that were scarcely investigated in past studies. Computational fluid dynamics (CFD) condensation models have been developed and validated. The suitability of helium as a substitute for hydrogen in experimental activities has been investigated by theoretical and computational analyses allowing to establish simple criteria for the scaling of condensation tests in the presence of a light non-condensable gas. (authors)