WorldWideScience

Sample records for buildup

  1. From detached to attached buildup complexes

    DEFF Research Database (Denmark)

    Rafaelsen, B.; Elvebakk, G.; Andreassen, K.;

    2008-01-01

    deposition and buildup growth bridged the detached platform with the attached platform. In the Bjarmeland Group (Lower Permian) 0.35-4.8 km wide, 1.5-27 km long and 60-420 m thick cool-water bryozoan-dominated straight, sinuous and continuous carbonate ridges or atoll-like ridges are located on top......Carbonate buildups were abundant during the Palaeozoic. Three-dimensional seismic data from the Finnmark Platform, Barents Sea, has been used to reconstruct the evolution of laterally extensive carbonate buildup complexes in space and time. The results suggest that the location of Upper Palaeozoic...

  2. BWR radiation buildup control with ionic zinc

    International Nuclear Information System (INIS)

    In 1983 a hypothesis was disclosed which suggested that the presence of ionic zinc in the reactor water of the BWR could reduce radiation buildup. This hypothesis was developed from correlations of plant data, and subsequently, from laboratory experiments which demonstrated clearly that ionic zinc inhibits the corrosion of stainless steel. The benefits of zinc addition have been measured at the Vallecitos Nuclear Center under and EPRI/GE project. Experimentation and analyses have been performed to evaluate the impact of intentional zinc addition on the IGSCC characteristics of primary system materials and on the performance of the nuclear fuel. It has been concluded that no negative effects are expected. The author conclude that the intentional addition of ionic zinc to the BWR reactor water at a concentration of approximately 10 ppb will provide major benefits in controlling the Co-60 buildup on primary system stainless steel surfaces. The intentional addition of zinc is now a qualified technique for use in BWRs

  3. Wave turbulence buildup in a vibrating plate

    CERN Document Server

    Auliel, Maria Ines; Mordant, Nicolas

    2015-01-01

    We report experimental and numerical results on the buildup of the energy spectrum in wave turbulence of a vibrating thin elastic plate. Three steps are observed: first a short linear stage, then the turbulent spectrum is constructed by the propagation of a front in wave number space and finally a long time saturation due to the action of dissipation. The propagation of a front at the second step is compatible with scaling predictions from the Weak Turbulence Theory.

  4. Hypergol Systems: Design, Buildup, and Operation

    Science.gov (United States)

    Baker, David; Rathgeber, Kurt

    2006-01-01

    This course was developed by personnel at the NASA JSC White Sands Test Facility in conjunction with the NASA Safety Training Center (NSTC). The NSTC was established in May 1991 by the NASA Headquarters Safety Directorate to provide up-to-date, high-quality, NASA specific safety training on location at NASA centers, or simultaneously to multiple centers over the Video Teleconferencing System (ViTS). Our desire is to establish and maintain a strong, long-lasting relationship with all NASA centers in order to fulfill your safety training needs on a cost-effective basis. Our ultimate goal is to provide a positive contribution to safe operations at NASA. NSTC Course 055 is a 2-day course discussing the safe usage of hypergols (hydrazine fuels and nitrogen tetroxide). During the course we will identify the hazards associated with hypergols including toxicity, reactivity, fire, and explosion. Management of risk is discussed in terms of the primary engineering controls design, buildup, and operation; and secondary controls personal protective equipment and detectors/monitors. The emphasis is on the design and buildup of compatible systems and the safe operation of these systems by technicians and engineers.

  5. Radioactivity build-up and decontamination (part 4)

    International Nuclear Information System (INIS)

    To establish a decontamination method of radioactive corrosion products in BWR primary coolant system, the radioactivity buildup after the decontamination was investigated for 304 stainless steel using a test loop simulating a BWR condition for 400 hours. The results show that; (1) Removal of the chromium in crud may be necessary to supress the activity re-buildup and the validity of Oxidation-reduction method with this process was proved. (2) The most significant activity re-buildup was shown when the original surface layer was exposed after complete removal of the crud. The exposure of chromium rich surface layer may account for the acceralation of activity buildup. (3) The re-buildup was supressed when a pre-filming by H2O2 (8 ppm 140 0C 24 hr) was applied after the electro-polishing up to the original surface layer. This supressing effect was also seen on new SUS304 surface. (author)

  6. Calculation of γ shielding buildup factor for certain light concrete

    International Nuclear Information System (INIS)

    Exposure buildup factors up to 40 mean free paths in ranging from 0.015 MeV to 15 MeV photon energy were calculated by using the Monte Carlo simulation code EGS4 for light concrete used in certain nuclear power plant. The calculation took into account effect of Bremsstrahlung, fluorescence and coherent (Rayleigh) scattering on the buildup factor. Then, the corresponding fitting parameters of the G-P fitting formula were presented by the geometrical progression approximation fitting formula. The method can get the y shielding buildup factors for any shielding thickness of the concrete and any photon energy. (authors)

  7. Analysis of pressure buildup data following a short flow period

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan, R.; Reynolds, A.C. Jr.; Meng, H.Z.

    1982-04-01

    Methods of analyzing buildup data following a short flow period are presented, discussed, and illustrated. A new type curve for uniform-flux and infinite-conductivity vertically fractured wells is presented. By matching buildup data with this new type curve, it is possible to determine the dimensionless flowing time before shut-in. A method for converting buildup data to equivalent drawdown data is discussed. This method can be used to combine buildup and drawdown data to obtain a longer band of data for type-curve matching. This method can be used for constant-rate production, constant-pressure production, and for the case where both pressure and rate vary during production. 17 refs.

  8. Prediction of sulphide build-up in filled sewer pipes.

    Science.gov (United States)

    Alani, Amir M; Faramarzi, Asaad; Mahmoodian, Mojtaba; Tee, Kong Fah

    2014-08-01

    Millions of dollars are being spent worldwide on the repair and maintenance of sewer networks and wastewater treatment plants. The production and emission of hydrogen sulphide has been identified as a major cause of corrosion and odour problems in sewer networks. Accurate prediction of sulphide build-up in a sewer system helps engineers and asset managers to appropriately formulate strategies for optimal sewer management and reliability analysis. This paper presents a novel methodology to model and predict the sulphide build-up for steady state condition in filled sewer pipes. The proposed model is developed using a novel data-driven technique called evolutionary polynomial regression (EPR) and it involves the most effective parameters in the sulphide build-up problem. EPR is a hybrid technique, combining genetic algorithm and least square. It is shown that the proposed model can provide a better prediction for the sulphide build-up as compared with conventional models. PMID:24956763

  9. Effect of pore pressure buildup on slowness of rupture propagation

    Science.gov (United States)

    Ougier-Simonin, A.; Zhu, W.

    2015-12-01

    Pore fluid pressure is known to play an important role in brittle fracture initiation and propagation, yet the underlying mechanisms remain unclear. We conducted triaxial experiments on saturated porous sandstones to investigate effects of pore pressure buildup on the slowness of shear rupture propagation at different confining pressures. At low to intermediate confinements, rocks fail by brittle faulting, and pore pressure buildup causes a reduction in rock's shear strength but does not induce measurable differences in slip behavior. When the confinement is high enough to prohibit dynamic faulting, rocks fail in the brittle-ductile transitional regime. In the transitional regime, pore pressure buildup promotes slip instability on an otherwise stably sliding fracture. Compared to those observed in the brittle regime, the slip rate, stress drop, and energy dissipated during rupture propagation with concurrent pore pressure buildup in the transitional regime are distinctively different. When decreasing confining pressure instead, the slip behavior resembles the ones of the brittle regime, emphasizing how the observed slowness is related to excess pore pressure beyond the effective pressure phenomenon. Analysis of the mechanical data using existing theoretical models confirms these observations. Quantitative microstructural analyses reveal that increasing pore pressure lessens the dilatancy hardening during failure, thus enhances slip along the localized zone in the transitional regime. Our experimental results suggest that pore pressure buildup induces slow slip in the transitional regime, and slip rates along a shear fracture may vary considerably depending on effective stress states.

  10. Dynamical analysis of the buildup process near resonance

    CERN Document Server

    Villavicencio, J; Villavicencio, Jorge; Romo, Roberto

    2000-01-01

    The time evolution of the buildup process inside a double-barrier system for off-resonance incidence energies is studied by considering the analytic solution of the time dependent Schr\\"{o}dinger equation with cutoff plane wave initial conditions. We show that the buildup process exhibits invariances under arbitrary changes on the system parameters, which can be successfully described by a simple and easy-to-use one-level formula. We find that the buildup of the off-resonant probability density is characterized by an oscillatory pattern modulated by the resonant case which governs the duration of the transient regime. This is evidence that off-resonant and resonant tunneling are two correlated processes, whose transient regime is characterized by the same transient time constant of two lifetimes.

  11. Characterising metal build-up on urban road surfaces.

    Science.gov (United States)

    Egodawatta, Prasanna; Ziyath, Abdul M; Goonetilleke, Ashantha

    2013-05-01

    Reliable approaches for predicting pollutant build-up are essential for accurate urban stormwater quality modelling. Based on the in-depth investigation of metal build-up on residential road surfaces, this paper presents empirical models for predicting metal loads on these surfaces. The study investigated metals commonly present in the urban environment. Analysis undertaken found that the build-up process for metals primarily originating from anthropogenic (copper and zinc) and geogenic (aluminium, calcium, iron and manganese) sources were different. Chromium and nickel were below detection limits. Lead was primarily associated with geogenic sources, but also exhibited a significant relationship with anthropogenic sources. The empirical prediction models developed were validated using an independent data set and found to have relative prediction errors of 12-50%, which is generally acceptable for complex systems such as urban road surfaces. Also, the predicted values were very close to the observed values and well within 95% prediction interval. PMID:23416742

  12. Semilog analysis of gas well drawdown and buildup data

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, A.C.; Bratvold, R.G.; Ding, W.

    1985-03-01

    The pseudo-pressure function is well understood and widely used for analyzing gas well drawdown and buildup data. The utility of the pseudo-time function for analyzing buildup data using drawdown type curves also has been established. Unfortunately, the pseudotime concept is often incorrectly applied when analyzing drawdown data by semilog methods. This work provides information on appropriate definitions of time which yield accurate analysis of data obtained under radial flow conditions. From the pratical viewpoint, the most important result is that there exist two Horner time ratios, one based on a normalized shut-in time and one based on shut-in pseudo-time which yield an accurate analysis of buildup data including the correct determination of average pressure using the liquid Matthews-Brons-Hazebroek functions.

  13. Semilog analysis of gas well drawdown and buildup data

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, A.C.; Bratvold, R.B.; Ding, W.

    1987-12-01

    The pseudopressure function is well understood and widely used for analyzing gas well drawdown and buildup data. The usefulness of the pseudotime function for analyzing buildup data with drawdown type curves has also been established. Unfortunately, the pseudotime concept is often incorrectly applied when drawdown data are analyzed by semilog methods. This work provides information on appropriate definitions of dimensionless time that yield accurate analysis of data obtained under radial flow conditions. From the practical viewpoint, the most important result is that two Horner time ratios exist - one based on a normalized shut-in time and one based on shut-in pseudotime - that yield an accurate analysis of buildup data, including the correct determination of average pressure using the liquid Matthews-Brons-Hazebroek (MBH) functions.

  14. E-Cloud Build-up in Grooved Chambers

    OpenAIRE

    Venturini, Marco

    2007-01-01

    We simulate electron cloud build-up in a grooved vacuum chamber including the effect of space charge from the electrons. We identify conditions for e-cloud suppression and make contact with previous estimates of an effective secondary electron yield for grooved surfaces.

  15. Energy Absorption and Exposure Buildup Factors of Essential Amino Acids

    Directory of Open Access Journals (Sweden)

    Ertuğrul Bursalıoğlu

    2014-01-01

    Full Text Available The effective atomic number and effective electron density in amino acids are of significant interest due to their use in various applications. The energy absorption buildup factors, exposure buildup factors, effective atomic numbers, and electron densities of essential amino acids such as Leucine (C6H13NO2, Lysine (C6H14N2O2, Methionine (C5H11NO2S, Phenylalanine (C9H11NO2, Threonine (C4H9NO3, Tryptophan (C11H12N2O2, Valine (C5H11NO2, Arginine (C6H14N4O2, and Histidine (C6H9N3O2 were determined theoretically in the energy range 0.015–15 MeV.

  16. Simulation on Buildup of Electron Cloud in Proton Circular Accelerator

    OpenAIRE

    Liu, Yu-Dong; Li, Kai-Wei

    2014-01-01

    Electron cloud interaction with high energy positive beam are believed responsible for various undesirable effects such as vacuum degradation, collective beam instability and even beam loss in high power proton circular accelerator. An important uncertainty in predicting electron cloud instability lies in the detail processes on the generation and accumulation of the electron cloud. The simulation on the build-up of electron cloud is necessary to further studies on beam instability caused by ...

  17. Dark solitons in laser radiation build-up dynamics.

    Science.gov (United States)

    Woodward, R I; Kelleher, E J R

    2016-03-01

    We reveal the existence of slowly decaying dark solitons in the radiation build-up dynamics of bright pulses in all-normal dispersion mode-locked fiber lasers, numerically modeled in the framework of a generalized nonlinear Schrödinger equation. The evolution of noise perturbations to quasistationary dark solitons is examined, and the significance of background shape and soliton-soliton collisions on the eventual soliton decay is established. We demonstrate the role of a restoring force in extending soliton interactions in conservative systems to include the effects of dissipation, as encountered in laser cavities, and generalize our observations to other nonlinear systems. PMID:27078358

  18. Dust buildup tests of heliostats and mirror specimens

    Energy Technology Data Exchange (ETDEWEB)

    Blackmon, J.B.

    1978-09-01

    Reflectivity variation data are presented for full-scale heliostats and sixty mirror specimens that were tested in a desert environment. Factors investigated included weather, site location, mirror type, and storage position. A method of obtaining reflectivity data for heliostats and specimens under field conditions is presented. Reflectivity degradation rates are determined for different storage positions and compared with weather conditions. Time-averaged reflectivity values are determined. Natural cleaning effectiveness of rain, snow, and frost is discussed. Heliostat operational procedures which appear to decrease reflectivity losses due to dust buildup are described.

  19. Simulation on Buildup of Electron Cloud in Proton Circular Accelerator

    CERN Document Server

    Liu, Yu-Dong

    2014-01-01

    Electron cloud interaction with high energy positive beam are believed responsible for various undesirable effects such as vacuum degradation, collective beam instability and even beam loss in high power proton circular accelerator. An important uncertainty in predicting electron cloud instability lies in the detail processes on the generation and accumulation of the electron cloud. The simulation on the build-up of electron cloud is necessary to further studies on beam instability caused by electron cloud. China Spallation Neutron Source (CSNS) is the largest scientific project in building, whose accelerator complex includes two main parts: an H- linac and a rapid cycling synchrotron (RCS). The RCS accumulates the 80Mev proton beam and accelerates it to 1.6GeV with a repetition rate 25Hz. During the beam injection with lower energy, the emerging electron cloud may cause a serious instability and beam loss on the vacuum pipe. A simulation code has been developed to simulate the build-up, distribution and dens...

  20. Energy buildup in sheared force-free magnetic fields

    Science.gov (United States)

    Wolfson, Richard; Low, Boon C.

    1992-01-01

    Photospheric displacement of the footpoints of solar magnetic field lines results in shearing and twisting of the field, and consequently in the buildup of electric currents and magnetic free energy in the corona. The sudden release of this free energy may be the origin of eruptive events like coronal mass ejections, prominence eruptions, and flares. An important question is whether such an energy release may be accompanied by the opening of magnetic field lines that were previously closed, for such open field lines can provide a route for matter frozen into the field to escape the sun altogether. This paper presents the results of numerical calculations showing that opening of the magnetic field is permitted energetically, in that it is possible to build up more free energy in a sheared, closed, force-free magnetic field than is in a related magnetic configuration having both closed and open field lines. Whether or not the closed force-free field attains enough energy to become partially open depends on the form of the shear profile; the results presented compare the energy buildup for different shear profiles. Implications for solar activity are discussed briefly.

  1. Orbit averaged radial buildup code for tandem mirror geometry

    International Nuclear Information System (INIS)

    The radial Fokker-Planck (RFP) model of A. Futch was modified to treat plasma buildup in the tandem mirror plug and center cell with a self-consistent model (TOARBUC). Two major changes have been made to the original version of this code. First, the center cell is treated as having separate electron and ion confining potentials with the ion potential having the opposite sign of that in a conventional mirror. Second, a two-electron-temperature treatment derived by R. Cohen was included in the present model to allow the plug and center cell to have different T/sub e/'s as observed in the experiment. The following sections explain these changes in greater detail

  2. Analysis of pressure buildup data influenced by wellbore phase redistribution

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.G.; Jones, J.R.; Reynolds, A.C.

    1986-10-01

    This work considers the influence of wellbore phase redistribution effects on the analysis of pressure buildup data. First, the authors show that the pressure responses observed when phase redistribution effects exist consist of three distinct types and delineate the conditions under which each type exists. Second, they investigate the reliability of Fair's type curves for analyzing pressure data. Third, for each type of pressure response, they provide rules for determining when the conventional semilog straight line will begin on a semilog plot of pressure data vs. time. They also consider general procedures that are based on Duhamel's principle for analyzing pressure data when sandface flow rates are also available. They discuss the application of these methods to analyze pressure data influenced by wellbore storage effects and investigate the effect that errors in the measured sandface rate have on the analysis.

  3. Electron-Cloud Build-Up: Theory and Data

    International Nuclear Information System (INIS)

    We present a broad-brush survey of the phenomenology, history and importance of the electron-cloud effect (ECE). We briefly discuss the simulation techniques used to quantify the electron-cloud (EC) dynamics. Finally, we present in more detail an effective theory to describe the EC density build-up in terms of a few effective parameters. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire 'ECLOUD' series. In addition, the proceedings of the various flavors of Particle Accelerator Conferences contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC.

  4. Contour Crafting Simulation Plan for Lunar Settlement Infrastructure Build-Up Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Economically viable and reliable building systems and tool sets are being sought, examined, and tested for extraterrestrial habitat and infrastructure buildup....

  5. Taxonomy of factors which influence heavy metal build-up on urban road surfaces.

    Science.gov (United States)

    Liu, An; Gunawardana, Chandima; Gunawardena, Janaka; Egodawatta, Prasanna; Ayoko, Godwin A; Goonetilleke, Ashantha

    2016-06-01

    Heavy metals build-up on urban road surfaces is a complex process and influenced by a diverse range of factors. Although numerous research studies have been conducted in the area of heavy metals build-up, limited research has been undertaken to rank these factors in terms of their influence on the build-up process. This results in limitations in the identification of the most critical factor/s for accurately estimating heavy metal loads and for designing effective stormwater treatment measures. The research study undertook an in-depth analysis of the factors which influence heavy metals build-up based on data generated from a number of different geographical locations around the world. Traffic volume was found to be the highest ranked factor in terms of influencing heavy metals build-up while land use was ranked the second. Proximity to arterial roads, antecedent dry days and road surface roughness has a relatively lower ranking. Furthermore, the study outcomes advances the conceptual understanding of heavy metals build-up based on the finding that with increasing traffic volume, total heavy metal build-up load increases while the variability decreases. The outcomes from this research study are expected to contribute to more accurate estimation of heavy metals build-up loads leading to more effective stormwater treatment design.

  6. Characterizing polycyclic aromatic hydrocarbon build-up processes on urban road surfaces.

    Science.gov (United States)

    Liu, Liang; Liu, An; Li, Dunzhu; Zhang, Lixun; Guan, Yuntao

    2016-07-01

    Reliable prediction models are essential for modeling pollutant build-up processes on urban road surfaces. Based on successive samplings of road deposited sediments (RDS), this study presents empirical models for mathematical replication of the polycyclic aromatic hydrocarbon (PAH) build-up processes on urban road surfaces. The contaminant build-up behavior was modeled using saturation functions, which are commonly applied in US EPA's Stormwater Management Model (SWMM). Accurate fitting results were achieved in three typical urban land use types, and the applicability of the models was confirmed based on their acceptable relative prediction errors. The fitting results showed high variability in PAH saturation value and build-up rate among different land use types. Results of multivariate data and temporal-based analyses suggested that the quantity and property of RDS significantly influenced PAH build-up. Furthermore, pollution sources, traffic parameters, road surface conditions, and sweeping frequency could synthetically impact the RDS build-up and RDS property change processes. Thus, changes in these parameters could be the main reason for variations in PAH build-up in different urban land use types. PMID:27086074

  7. Energy absorption buildup factors for thermoluminescent dosimetric materials and their tissue equivalence

    DEFF Research Database (Denmark)

    Manohara, S.R.; Hanagodimath, S.M.; Gerward, Leif

    2010-01-01

    Gamma ray energy-absorption buildup factors were computed using the five-parameter geometric progression (G-P) fitting formula for seven thermoluminescent dosimetric (TLD) materials in the energy range 0.015-15 MeV, and for penetration depths up to 40 mfp (mean free path). The generated energy......-absorption buildup factor data have been studied as a function of penetration depth and incident photon energy. Buildup factors determined in the present work should be useful in radiation dosimetry, diagnostics and therapy. The tissue equivalence of TLD materials is also discussed....

  8. Application of Monte Carlo code EGS4 to calculate gamma exposure buildup factors

    International Nuclear Information System (INIS)

    Exposure buildup factors up to 40 mean free paths ranging from 0.015 MeV to 15 MeV photon energy were calculated by using the Monte Carlo simulation code EGS4 for ordinary concrete. The calculation involves PHOTX cross section library, a point isotropic source, infinite uniform medium model and a particle splitting method and considers the Bremsstrahlung, fluorescent effect, correlative (Rayleigh) scatter. The results were compared with the relevant data. Results show that the data of the buildup factors calculated by the Monte Carlo code EGS4 was reliable. The Monte Carlo method can be used widely to calculate gamma-ray exposure buildup factors. (authors)

  9. Modeling of gamma-ray energy absorption buildup factors using response surface method

    International Nuclear Information System (INIS)

    Buildup factors are always useful for practical computations in gamma-ray shield design. Generally point kernel method being easier to handle is adopted for shielding calculations. This method models a gamma ray directly at the evaluation point without scattering which is multiplied by buildup factors to obtain the gamma dose rate. The American Nuclear Society Standard Committee working group (ANSI/ANS-6.4.3-1991) has compiled the energy absorption and exposure buildup factors from 1 mean free path to 40 mean free paths as a standard reference data base for a large number of elements including water, air and concrete. Literature study reveals that there is a substantially significant disagreement in the buildup factor data by different approximating formulae. In view of this, it is required to compute or predict the buildup factor for those materials. The buildup factor data have been computed by various codes. Some of the codes are ASFIT (Gopinath and Sakamoto et al, 1971), PALLAS (Takeuchi and Tanaka, 1984) and EGS4 (Nelson et al, 1985). Taylor (1954), Berger (1956), Capo (1958) have fitted Goldstein and Wilkins (1954) data to construct parametric buildup factor formulae. Harimaet et al. (1986) has developed geometric progress fitting formula for the ANSI/ANS-6.4.3 (ANSI, 1991). The energy absorption buildup factor is defined as the photon buildup factor in which the quantity of interest is the absorbed or deposited energy in the shield medium and the detector response function is that of absorption in the material. Geometric progression buildup factor formula was simplified using the new modeling (fitting algorithm) of gamma ray energy absorption buildup factor. Advantage of having the simplification of buildup factor formula provides the easiness of usage of point kernel method based gamma shielding in the sense that analytic expression of collided flux can be easily constructed. Furthermore, that analytical expression of collided flux can be optimized to

  10. Study of influence of buildup factor form on simulated radiographic image

    Directory of Open Access Journals (Sweden)

    Marinković Predrag

    2009-01-01

    Full Text Available The objective of the study presented in this paper is the analysis of influence of different buildup factor forms on a simulated radiographic image. Simulated radiographic images are obtained by means of the ray-tracing technique. Scattered photons are modelled using the generally accepted geometric progression form, linear form and tabulated data of buildup factors. Simulated images were compared to the reference results obtained by Monte Carlo calculation. The best agreement to Monte Carlo simulated images is achieved for the geometric progression form of buildup factor.

  11. Well-test analysis for solution-gas-drive reservoirs. Part 2; Buildup analysis

    Energy Technology Data Exchange (ETDEWEB)

    Serra, K.V.; Peres, A.M.M. (PETROBRAS, Rio de Janeiro, RJ (Brazil)); Reynolds, A.C. (Tulsa Univ., OK (USA))

    1990-06-01

    This work presents new analysis methods for pressure-buildup data from a well completed in a solution-gas-drive reservoir. New procedures for estimating effective phase permeabilities as functions of pressure and saturation are presented.

  12. Analysis of short-time buildup data for finite-conductivity fractures

    Energy Technology Data Exchange (ETDEWEB)

    Rosato, N.D.; Bennett, C.O.; Raghavan, R.; Reynolds, A.C.

    1982-10-01

    A finite-conductivity vertical fracture intersecting a well is considered. The well is produced at a constant rate or at a constant pressure and then is shut in. The pressure response during the buildup period and the pressure or rate response during the production period are obtained from a numerical model. In this work the authors discuss the analysis of pressure buildup data following a short flow period. The authors present a buildup type curve to analyze pressure buildup data when the pressure (or rate) response is influenced by only the bilinear flow period. This type curve can be used to estimate the fracture flow capacity and a lower limit for the fracture half-length. It will be useful when the equivalent-time or the equivalent-drawdown concepts cannot be used. The authors discuss strengths and limitations of the equivalenttime method proposed in the literature. The theoretical basis for this procedure is provided.

  13. Radionuclide buildup in FFTF [Fast Flux Test Facility] heat transport system cells

    International Nuclear Information System (INIS)

    The purpose of the work reported in this paper was to measure the radionuclide buildup in primary heat transport system cell No. 3 at the Fast Flux Test Facility (FFTF) and to compare the results with predicted values from a model based on experimental studies and experience at similar reactors. The information obtained is used for maintenance planning and to enhance ability to assess radionuclide buildup in the future at FFTF and in other reactors

  14. Assessing uncertainty in pollutant build-up and wash-off processes.

    Science.gov (United States)

    Wijesiri, Buddhi; Egodawatta, Prasanna; McGree, James; Goonetilleke, Ashantha

    2016-05-01

    Assessing build-up and wash-off process uncertainty is important for accurate interpretation of model outcomes to facilitate informed decision making for developing effective stormwater pollution mitigation strategies. Uncertainty inherent to pollutant build-up and wash-off processes influences the variations in pollutant loads entrained in stormwater runoff from urban catchments. However, build-up and wash-off predictions from stormwater quality models do not adequately represent such variations due to poor characterisation of the variability of these processes in mathematical models. The changes to the mathematical form of current models with the incorporation of process variability, facilitates accounting for process uncertainty without significantly affecting the model prediction performance. Moreover, the investigation of uncertainty propagation from build-up to wash-off confirmed that uncertainty in build-up process significantly influences wash-off process uncertainty. Specifically, the behaviour of particles <150 μm during build-up primarily influences uncertainty propagation, resulting in appreciable variations in the pollutant load and composition during a wash-off event. PMID:26840516

  15. Analysis of the build-up of semi and non volatile organic compounds on urban roads.

    Science.gov (United States)

    Mahbub, Parvez; Ayoko, Godwin A; Goonetilleke, Ashantha; Egodawatta, Prasanna

    2011-04-01

    Vehicular traffic in urban areas may adversely affect urban water quality through the build-up of traffic generated semi and non volatile organic compounds (SVOCs and NVOCs) on road surfaces. The characterisation of the build-up processes is the key to developing mitigation measures for the removal of such pollutants from urban stormwater. An in-depth analysis of the build-up of SVOCs and NVOCs was undertaken in the Gold Coast region in Australia. Principal Component Analysis (PCA) and Multicriteria Decision tools such as PROMETHEE and GAIA were employed to understand the SVOC and NVOC build-up under combined traffic scenarios of low, moderate, and high traffic in different land uses. It was found that congestion in the commercial areas and use of lubricants and motor oils in the industrial areas were the main sources of SVOCs and NVOCs on urban roads, respectively. The contribution from residential areas to the build-up of such pollutants was hardly noticeable. It was also revealed through this investigation that the target SVOCs and NVOCs were mainly attached to particulate fractions of 75-300 μm whilst the redistribution of coarse fractions due to vehicle activity mainly occurred in the >300 μm size range. Lastly, under combined traffic scenario, moderate traffic with average daily traffic ranging from 2300 to 5900 and average congestion of 0.47 were found to dominate SVOC and NVOC build-up on roads.

  16. Electron contamination and build-up doses in conformal radiotherapy fields.

    Science.gov (United States)

    Hounsell, A R; Wilkinson, J M

    1999-01-01

    The dose in the build-up region depends upon the primary photon beam, backscattered radiation from the patient and contamination radiation from outside the patient. In this paper, a model based on measured data is proposed which allows the build-up dose for arbitrarily shaped treatment fields to be determined. The dose in the build-up region is assumed to comprise a primary photon component and a contamination component that is a function of the field size and shape. This contamination component, for modelling purposes, is subdivided into contributions that correspond to elements of 1 cm by 1 cm cross-sectional area at the plane of the isocentre. The magnitude of these components has been obtained by fitting measured data to an exponential function. The exponent was found to vary linearly with depth for energies between 4 MV and 20 MV. The coefficient decreased linearly with depth at 4, 6 and 8 MV, but exhibited a broad build-up region at 20 MV. The primary component, in the build-up region, could be approximated by a 100 - (100 - PSD) e(-mu d) function, where PSD is the primary surface dose. The values obtained during the fitting procedure were used to calculate dose in the build-up region for arbitrarily shaped fields. Good agreement was found in each case. PMID:10071874

  17. Understanding the build-up of SMBH and Galaxies

    Science.gov (United States)

    Carrera, Francisco; Georgakakis, Antonis; Ueda, Yoshihiro; Akylas, Thanassis; Lanzuisi, Giorgio; Castello, N.

    2015-09-01

    . The excellent survey capabilities of Athena/WFI (effective area, angular resolution, field of view) will allow to measure the incidence of feedback in the shape of warm absorbers and Ultra Fast Outflows among the general population of AGN, as well as to complete the census of black hole growth by detecting and characterising significant samples of the most heavily obscured (including Compton thick) AGN, to redshifts z~3-4. The outstanding spectral throughput and resolution of Athena/X-IFU will permit measuring the energetics of those outflows to assess their influence on their host galaxies. The demographics of the heavily obscured and outflowing populations relative to their hosts are fundamental for understanding how major black hole growth events relate to the build-up of galaxies.

  18. Analysis of build-up of heavy metals and volatile organics on urban roads in gold coast, Australia.

    Science.gov (United States)

    Mahbub, Parvez; Goonetilleke, Ashantha; Ayoko, Godwin A; Egodawatta, Prasanna; Yigitcanlar, Tan

    2011-01-01

    Urban water quality can be significantly impaired by the build-up of pollutants such as heavy metals and volatile organics on urban road surfaces due to vehicular traffic. Any control strategy for the mitigation of traffic related build-up of heavy metals and volatile organic pollutants should be based on the knowledge of their build-up processes. In the study discussed in this paper, the outcomes of a detailed experimental investigation into build-up processes of heavy metals and volatile organics are presented. It was found that traffic parameters such as average daily traffic, volume over capacity ratio and surface texture depth had similar strong correlations with the build-up of heavy metals and volatile organics. Multicriteria decision analyses revealed that that the 1-74 microm particulate fraction of total suspended solids (TSS) could be regarded as a surrogate indicator for particulate heavy metals in build-up and this same fraction of total organic carbon could be regarded as a surrogate indicator for particulate volatile organics build-up. In terms of pollutants affinity, TSS was found to be the predominant parameter for particulate heavy metals build-up and total dissolved solids was found to be the predominant parameter for the potential dissolved particulate fraction in heavy metals buildup. It was also found that land use did not play a significant role in the build-up of traffic generated heavy metals and volatile organics.

  19. Characterizing heavy metal build-up on urban road surfaces: Implication for stormwater reuse

    International Nuclear Information System (INIS)

    Stormwater reuse is increasingly popular in the worldwide. In terms of urban road stormwater, it commonly contains toxic pollutants such as heavy metals, which could undermine the reuse safety. The research study investigated heavy metal build-up characteristics on urban roads in a typical megacity of South China. The research outcomes show the high variability in heavy metal build-up loads among different urban road sites. The degree of traffic congestion and road surface roughness was found to exert a more significant influence on heavy metal build-up rather than traffic volume. Due to relatively higher heavy metal loads, stormwater from roads with more congested traffic conditions or rougher surfaces might be suitable for low-water-quality required activities while the stormwater from by-pass road sections could be appropriate for relatively high-water-quality required purposes since the stormwater could be relatively less polluted. Based on the research outcomes, a decision-making process for heavy metals based urban road stormwater reuse was proposed. The new finding highlights the importance to undertaking a “fit-for-purpose” road stormwater reuse strategy. Additionally, the research results can also contribute to enhancing stormwater reuse safety. - Highlights: • Heavy metal (HM) build-up varies with traffic and road surface conditions. • Traffic congestion and surface roughness exert a higher impact on HM build-up. • A “fit-for-purpose” strategy could suit urban road stormwater reuse

  20. Characterizing heavy metal build-up on urban road surfaces: Implication for stormwater reuse

    Energy Technology Data Exchange (ETDEWEB)

    Liu, An [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); Cooperative Research and Education Centre for Environmental Technology, Kyoto University–Tsinghua University, 518055 Shenzhen (China); Liu, Liang; Li, Dunzhu [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); Guan, Yuntao, E-mail: guanyt@tsinghua.edu.cn [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); School of Environment, Tsinghua University, Beijing 100084 (China)

    2015-05-15

    Stormwater reuse is increasingly popular in the worldwide. In terms of urban road stormwater, it commonly contains toxic pollutants such as heavy metals, which could undermine the reuse safety. The research study investigated heavy metal build-up characteristics on urban roads in a typical megacity of South China. The research outcomes show the high variability in heavy metal build-up loads among different urban road sites. The degree of traffic congestion and road surface roughness was found to exert a more significant influence on heavy metal build-up rather than traffic volume. Due to relatively higher heavy metal loads, stormwater from roads with more congested traffic conditions or rougher surfaces might be suitable for low-water-quality required activities while the stormwater from by-pass road sections could be appropriate for relatively high-water-quality required purposes since the stormwater could be relatively less polluted. Based on the research outcomes, a decision-making process for heavy metals based urban road stormwater reuse was proposed. The new finding highlights the importance to undertaking a “fit-for-purpose” road stormwater reuse strategy. Additionally, the research results can also contribute to enhancing stormwater reuse safety. - Highlights: • Heavy metal (HM) build-up varies with traffic and road surface conditions. • Traffic congestion and surface roughness exert a higher impact on HM build-up. • A “fit-for-purpose” strategy could suit urban road stormwater reuse.

  1. Gamma-ray energy buildup factor calculations and shielding effects of some Jordanian building structures

    Science.gov (United States)

    Sharaf, J. M.; Saleh, H.

    2015-05-01

    The shielding properties of three different construction styles, and building materials, commonly used in Jordan, were evaluated using parameters such as attenuation coefficients, equivalent atomic number, penetration depth and energy buildup factor. Geometric progression (GP) method was used to calculate gamma-ray energy buildup factors of limestone, concrete, bricks, cement plaster and air for the energy range 0.05-3 MeV, and penetration depths up to 40 mfp. It has been observed that among the examined building materials, limestone offers highest value for equivalent atomic number and linear attenuation coefficient and the lowest values for penetration depth and energy buildup factor. The obtained buildup factors were used as basic data to establish the total equivalent energy buildup factors for three different multilayer construction styles using an iterative method. The three styles were then compared in terms of fractional transmission of photons at different incident photon energies. It is concluded that, in case of any nuclear accident, large multistory buildings with five layers exterior walls, style A, could effectively attenuate radiation more than small dwellings of any construction style.

  2. Analysis of pressure-buildup data from a well in a multiwell system

    Energy Technology Data Exchange (ETDEWEB)

    Onur, M. (Istanbul Technical Univ. (TR)); Serra, K.V. (Petrobras, S.A. (BR)); Reynolds, A.C. (Tulsa Univ., OK (United States))

    1991-03-01

    This paper investigates the buildup response of a well located in a system of producing wells completed in a closed, bounded reservoir. Using an analysis method based on the pressure derivative, the authors show that the drainage area of the well (at the instant of shut-in) and the flow-capacity (permeability-thickness) product can be computed directly from the derivative of pressure-buildup data even in cases when conventional semilog straight lines are not well defined. The analysis methods assume that the buildup-surveyed well has established its own drainage area before shut-in. For a system of wells located in a closed, bounded reservoir, this means that pseudo-steady-state flow prevails at the instant of shut-in. The authors also present a second method for estimating a well's drainage area from pressure-buildup data. The second method relies on the fact that during buildup, the well's shut-in pressure increases to a maximum and then decreases as a result of interference from neighboring producing wells. It is shown that the maximum shut-in pressure, and the time at which it occurs, often can also be used to compute the well's drainage area st the instant of shut-in and the average pressure in this drainage area.

  3. Contour Crafting Simulation Plan for Lunar Settlement Infrastructure Build-Up

    Science.gov (United States)

    Khoshnevis, B.; Carlson, A.; Leach N.; Thangavelu, M.

    2016-01-01

    Economically viable and reliable building systems and tool sets are being sought, examined and tested for extraterrestrial infrastructure buildup. This project focused on a unique architecture weaving the robotic building construction technology with designs for assisting rapid buildup of initial operational capability Lunar and Martian bases. The project aimed to study new methodologies to construct certain crucial infrastructure elements in order to evaluate the merits, limitations and feasibility of adapting and using such technologies for extraterrestrial application. Current extraterrestrial settlement buildup philosophy holds that in order to minimize the materials needed to be flown in, at great transportation costs, strategies that maximize the use of locally available resources must be adopted. Tools and equipment flown as cargo from Earth are proposed to build required infrastructure to support future missions and settlements on the Moon and Mars.

  4. Limit equilibrium analysis of translational failure of landfills under different leachate buildup conditions

    Institute of Scientific and Technical Information of China (English)

    Qian Xuede

    2008-01-01

    Excessive leachate levels in landfills can be a major triggering mechanism for translational failure. The scope of this paper is to present the development of the calculation methods for limit equilibrium analysis of translational failure of landfills and the effects of parametric variation on the factor of safety (FS) of landfills under different leachate buildup conditions. During the development of the calculation methods, 4 leachate buildup conditions are considered. The FS for an interface with high friction angle and low apparent cohesion generally drops much more quickly when leachate levels are increased than that for an interface under inverse conditions. The critical interface of a muitilayer liner system with the lowest FS for the entire waste mass can shift from one to another with changes in the leachate levels. The different interfaces of a multilayer liner will have different FS-values under different leachate buildup conditions.

  5. Investigations of mass attenuation coefficients and exposure buildup factors of some low-Z building materials

    International Nuclear Information System (INIS)

    Highlights: ► Low cost materials show better shielding effectiveness than concrete for E > 1 MeV. ► Correlation between Zeff and EBF for shielding effectiveness. ► Buildup factors are necessary to study shielding properties of materials. - Abstract: To check the gamma ray shielding properties of selected low-Z building materials such as Soil-I, Soil-II, Dolomite, Gypsum, Igneous Rock and Lime Stone, some parameters of dosimetric interest have been investigated in the energy range 0.015–15 MeV. The photon interactions with the samples have been discussed mainly in terms of mass attenuation coefficient, equivalent atomic number and exposure buildup factor. From the present investigations, it has been concluded that the values of exposure buildup factors are very large in the medium energy region and Soil-I acts as best gamma ray shielding material among the selected samples.

  6. Change in surface SP caused by pressure buildup observed at the Nigorikawa geothermal area; Nigorikawa chiiki ni okeru atsuryoku buildup ji no shizen den`i henka

    Energy Technology Data Exchange (ETDEWEB)

    Yasukawa, K.; Yano, Y.; Matsushima, N.; Ishido, T. [Geological Survey of Japan, Tsukuba (Japan); Takahashi, M.; Suzuki, I.; Aoyama, K.; Kuwano, T.

    1996-10-01

    To examine the effect of change of subsurface flow system on the surface SP (self potential), SP measurements were carried out before and after the pressure buildup and drawdown during the periodic inspection at Nigorikawa area. Relation between the SP distribution and the observed data was also examined by 2-D numerical simulation. Tendency was found that the SP increased gradually with the production near the production well, decreased during the pressure buildup, and increased again during the drawdown. There were some points having the reverse tendency in the surrounding area. Behavior during the pressure buildup and drawdown was not clear. The resistivity near the ground surface was low ranging between 2 and 5 ohm/m within the Nigorikawa basin. The variation of SP was not so large when compared with the measuring error. The SP profiles on the secondary section passing in the center of caldera at the production stop and at one week after the production start were well corresponded with the profiles under natural conditions which were reproduces using the 2-D model. It was considered that the SP profile before the production stop was affected by the production. 12 refs., 6 figs., 1 tab.

  7. The Analysis of Performance on Spring-Supported Thrust Pads Inclusive of One-Dimensional Pressure Build-up

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In the paper, a solution of one dimensional fore-region pressure build-up is put forward. The performance of spring-supported thrust bearing is carried out with 3-dimensional thermo-elasto hydrodynamic (TEHD) lubrication theory inclusive of inlet pressure build-up, thermal-elastic distortion of pad and thermal effect. The effects of fore-region pressure build-up and the variation of some operating conditions on the performance of the pad are studied.

  8. The needs for prediction and real-time monitoring for the flare build-up study

    Science.gov (United States)

    Svestka, Z.

    1979-01-01

    Similarities between plasma instabilities occurring in the magnetospheric tail and in active regions on the Sun are discussed. Intense observations of the flare build-up processes on the Sun planned for May and June 1980 as a part of the Solar Maximum Year are described.

  9. Implications for flare build-up and heating from observations made by OSO-7

    Science.gov (United States)

    Neupert, W. M.

    1975-01-01

    The evolution of the EUV and soft X-ray emission in the event on January 19, 1972 are discussed in terms of the slow (passive) and fast (active) phases of flare evolution that were previously discussed. The implications are summarized for a flare build-up model which was derived-from these observations.

  10. On the reversibility of cake buildup and compression in a membrane bioreactor

    DEFF Research Database (Denmark)

    Jørgensen, Mads Koustrup; Keiding, Kristian; Christensen, Morten Lykkegaard

    2014-01-01

    Fouling in a membrane bioreactor was studied by describing the reversibility of fouling developing during short-term experiments. Data were fitted to a recently proposed model of the buildup and compression of fouling layers. Shear stepping experiments performed to characterize the efficiency...

  11. Finite and infinite system gamma ray buildup factor calculations with detailed physics.

    Science.gov (United States)

    Atak, Haluk; Çelikten, Osman Şahin; Tombakoğlu, Mehmet

    2015-11-01

    Examination of physical interactions of photons in materials is a significant subject for buildup factor studies. In most of the buildup calculations, by default, coherent (Rayleigh) scattering is ignored and the Compton scattering is modeled by free-electron Klein-Nishina formula with "simple physics" treatment. In this work, photon buildup factors are calculated for many different cases including "detailed physics" by taking into account coherent and bound-electron Compton scatterings with the Monte Carlo code, MCNP5, and the results are compared with the literature values. They are computed for point isotropic photon sources up to depths of 20 mean free paths and at the three photon energies most widely used (0.06, 0.6 and 6MeV). Calculations are made for both finite and infinite homogeneous ordinary water media. It is concluded that Coherent scattering is very dominant at low energies and for deep penetrations and assumed physical approximation (simple/detailed, finite/infinite) is the critical point for determining shielding material dimensions. After all, it can be stated that all parametric assumptions should be clearly given and indicated in the tabulation of photon buildup factors. PMID:26218451

  12. Repair bond strength of dual-cured resin composite core buildup materials.

    Science.gov (United States)

    El-Deeb, Heba A; Ghalab, Radwa M; Elsayed Akah, Mai M; Mobarak, Enas H

    2016-03-01

    The reparability of dual-cured resin composite core buildup materials using a light-cured one following one week or three months storage, prior to repair was evaluated. Two different dual-cured resin composites; Cosmecore™ DC automix and Clearfil™ DC automix core buildup materials and a light-cured nanofilled resin composite; Filtek™ Z350 XT were used. Substrate specimens were prepared (n = 12/each substrate material) and stored in artificial saliva at 37 °C either for one week or three months. Afterward, all specimens were ground flat, etched using Scotchbond™ phosphoric acid etchant and received Single Bond Universal adhesive system according to the manufacturers' instructions. The light-cured nanofilled resin composite (Filtek™ Z350 XT) was used as a repair material buildup. To determine the cohesive strength of each solid substrate material, additional specimens from each core material (n = 12) were prepared and stored for the same periods. Five sticks (0.8 ± 0.01 mm(2)) were obtained from each specimen (30 sticks/group) for microtensile bond strength (μTBS) testing. Modes of failure were also determined. Two-way ANOVA revealed a significant effect for the core materials but not for the storage periods or their interaction. After one week, dual-cured resin composite core buildup materials (Cosmecore™ DC and Clearfil™ DC) achieved significantly higher repair μTBS than the light-cured nanofilled resin composite (Filtek™ Z350 XT). However, Clearfil™ DC revealed the highest value, then Cosmecore™ DC and Filtek™ Z350 XT, following storage for 3-month. Repair strength values recovered 64-86% of the cohesive strengths of solid substrate materials. The predominant mode of failure was the mixed type. Dual-cured resin composite core buildup materials revealed acceptable repair bond strength values even after 3-month storage.

  13. Repair bond strength of dual-cured resin composite core buildup materials.

    Science.gov (United States)

    El-Deeb, Heba A; Ghalab, Radwa M; Elsayed Akah, Mai M; Mobarak, Enas H

    2016-03-01

    The reparability of dual-cured resin composite core buildup materials using a light-cured one following one week or three months storage, prior to repair was evaluated. Two different dual-cured resin composites; Cosmecore™ DC automix and Clearfil™ DC automix core buildup materials and a light-cured nanofilled resin composite; Filtek™ Z350 XT were used. Substrate specimens were prepared (n = 12/each substrate material) and stored in artificial saliva at 37 °C either for one week or three months. Afterward, all specimens were ground flat, etched using Scotchbond™ phosphoric acid etchant and received Single Bond Universal adhesive system according to the manufacturers' instructions. The light-cured nanofilled resin composite (Filtek™ Z350 XT) was used as a repair material buildup. To determine the cohesive strength of each solid substrate material, additional specimens from each core material (n = 12) were prepared and stored for the same periods. Five sticks (0.8 ± 0.01 mm(2)) were obtained from each specimen (30 sticks/group) for microtensile bond strength (μTBS) testing. Modes of failure were also determined. Two-way ANOVA revealed a significant effect for the core materials but not for the storage periods or their interaction. After one week, dual-cured resin composite core buildup materials (Cosmecore™ DC and Clearfil™ DC) achieved significantly higher repair μTBS than the light-cured nanofilled resin composite (Filtek™ Z350 XT). However, Clearfil™ DC revealed the highest value, then Cosmecore™ DC and Filtek™ Z350 XT, following storage for 3-month. Repair strength values recovered 64-86% of the cohesive strengths of solid substrate materials. The predominant mode of failure was the mixed type. Dual-cured resin composite core buildup materials revealed acceptable repair bond strength values even after 3-month storage. PMID:26966567

  14. Simulations of the electron cloud buildups and suppressions in Tevatron and main injector

    International Nuclear Information System (INIS)

    To assess the effects of the electron cloud on Main Injector intensity upgrades, simulations of the cloud buildup were carried out using POSINST and compared with ECLOUD. Results indicate that even assuming an optimistic 1.3 maximum secondary electron yield, the electron cloud remains a serious concern for the planned future operational mode with 500 bunches, 3e11 proton per bunch. Electron cloud buildup can be mitigated in various ways. We consider a plausible scenario involving solenoids in straight section and a single clearing strip electrode (like SNEG in Tevatron) held at a potential of 500V. Simulations with parameters corresponding to Tevatron and Main Injector operating conditions at locations where special electron cloud detectors have been installed have been carried out and are in satisfactory agreement with preliminary measurements

  15. Calculation of point isotropic buildup factors of gamma rays for water and lead

    Directory of Open Access Journals (Sweden)

    A. S. H.

    2001-12-01

    Full Text Available   Exposure buildup factors for water and lead have been calculated by the Monte-Carlo method for an isotropic point source in an infinite homogeneous medium, using the latest cross secions available on the Internet. The types of interactions considered are ,photoelectric effect, incoherent (or bound-electron Compton. Scattering, coherent (or Rayleigh scattering and pair production. Fluorescence radiations have also been taken into acount for lead. For each material, calculations were made at 10 gamma ray energies in the 40 keV to 10 MeV range and up to penetration depths of 10 mean free paths at each energy point. The results presented in this paper can be considered as modified gamma ray exposure buildup factors and be used in radiation shielding designs.

  16. Effects of hydrogen water chemistry on radiation field buildup in BWRs

    International Nuclear Information System (INIS)

    A number of boiling water reactor (BWR) plants worldwide are currently operating under hydrogen water chemistry (HWC). In some reactors, when switching from normal water chemistry (NWC) to HWC, an increase in the recirculation piping dose rates has been observed. Understanding the key factors which affect the dose rate increase is the subject of our current investigation. Laboratory experiments have been conducted under controlled chemistry conditions to examine the rates of 60Co deposition and the characteristic of oxide films formed on stainless steel surfaces. The activity buildup data obtained from two operating BWRs are carefully reviewed and discussed in this paper. Based on both laboratory and reactor data, a plausible mechanism of enhanced activity buildup under HWC conditions is hypothesized. (orig.)

  17. Secondary side TSP deposit buildup: lab test investigation focused on electrokinetic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Barale, M.; Guillodo, M.; Foucault, M., E-mail: Morgan.Barale@areva.com [AREVA NP SAS, Technical Centre, Le Creusot (France); Ryckelynck, N.; Clinard, M-H.; Chahma, F.; Brun, C. [AREVA NP SAS, Chemistry and Radiochemistry Group, Paris (France); Corredera, G. [Electricite de France, Centre d' Expertise et d' Inspection dans les domaines de la Realisation et de l' Exploitation, Saint-Denis (France)

    2010-07-01

    Deposit buildup which caused the clogging of the 'foils' of the upper tube-support-plates (TSP) inside a PWR steam generator of French NPPs in 2006 presents certain similarities with deposits observed in lab tests performed in secondary coolant chemistry at the Technical Centre of AREVA NP in 2002. The mechanism of TSP clogging seems not to present obvious phenomenological links with the fouling of the free span of SG since deposits buildup is quite uniform and is currently related to a surface boiling effect due to the surface heat flux. A specific mechanism could account for TSP clogging. In particular, electrokinetic effects were investigated by EDF-CEIDRE and AREVA NP SAS in the framework of a lab test program started in 2007. The electrokinetic approach is to consider that the coupling of local hydrodynamic and surface electrochemistry could lead to the formation of a very localized and heterogeneous deposit at the leading edge between both TSP and SG tubing material. Electrokinetic effects can lead to the oxidation and/or the precipitation of ferrous ions and to a variation of the electrokinetic potential which can produce strong attraction of iron oxide colloids. These electrokinetic effects are dependent of the T/H and local hydrodynamic conditions and surface electrochemistry explaining. The objective of this EDF-AREVA lab test program is to investigate the role of secondary chemistry coolant (pH, DH, N{sub 2}H{sub 4}, amine, redox) and of the nature of materials (SS, Ni base alloy) on deposit buildup. Properties of oxide surface and zeta potential of oxidized metallic materials have been also determined at temperature to understand their potential contribution on mechanism of TSP clogging in secondary side chemistry coolant. In this paper, a set of specific experiments carried out in this frame have been presented and discussed, paying particular attention to the effects of electrokinetic considerations and surface charges at oxide

  18. State Interests and Symbolism in India’s Nuclear Build-Up

    OpenAIRE

    Frey, Karsten

    2002-01-01

    India’s nuclear build-up, which culminated in the 1998 nuclear tests and India’s subsequent self-declaration as a nuclear power, bears several puzzles for academic research in the field of strategic studies, as it appears difficult to identify clear strategic motives behind it. In its relations to arch rival Pakistan, the introduction of nuclear weapons was strategically rather counter productive for India, as the equalising effects of these weapons diminished much of India’s overwhelming sup...

  19. Shielded button electrodes for time-resolved measurements of electron cloud buildup

    OpenAIRE

    Crittenden, James A.; Billing, Michael G.; Li, Yulin; Palmer, Mark A.; Sikora, John P.

    2013-01-01

    We report on the design, deployment and signal analysis for shielded button electrodes sensitive to electron cloud buildup at the Cornell Electron Storage Ring. These simple detectors, derived from a beam-position monitor electrode design, have provided detailed information on the physical processes underlying the local production and lifetime of electron densities in the storage ring. Digitizing oscilloscopes are used to record electron fluxes incident on the vacuum chamber wall in 1024 time...

  20. Simulations of electron cloud build-up and saturation in the APS

    OpenAIRE

    Harkay, K.C.; Rosenberg, R. A.; Furman, M.A.; Pivi, M.

    2002-01-01

    In studies with positron beams in the Advanced Photon Source, a dramatic amplification was observed in the electron cloud for certain bunch current and bunch spacings. In modeling presented previously, we found qualitative agreement with the observed beam-induced multipacting condition, provided reasonable values were chosen for the secondary electron yield parameters, including the energy distribution. In this paper, we model and discuss the build-up and saturation process observed ove...

  1. Electron Cloud Buildup Characterization Using Shielded Pickup Measurements and Custom Modeling Code at CESRTA

    OpenAIRE

    Crittenden, James A.; Sikora, John P.

    2013-01-01

    The Cornell Electron Storage Ring Test Accelerator experimental program includes investigations into electron cloud buildup, applying various mitigation techniques in custom vacuum chambers. Among these are two 1.1-m-long sections located symmetrically in the east and west arc regions. These chambers are equipped with pickup detectors shielded against the direct beam-induced signal. They detect cloud electrons migrating through an 18-mm-diameter pattern of small holes in the top of the chambe...

  2. Exposure Buildup Factors for Heavy Metal Oxide Glass: A Radiation Shield

    DEFF Research Database (Denmark)

    Manonara, S. R.; Hanagodimath, S. M.; Gerward, Leif;

    2011-01-01

    Gamma ray exposure buildup factors for three Heavy Metal Oxide (HMO) glass systems, viz. PbO-Bi2O3-B2O3, PbO-B2O3, and Bi2O3-B2O3 glasses are presented. The computations were done by interpolation method using the Geometric Progression fitting formula and ANSI/ANS-6.4.3 library for the energy range...

  3. Flare build-up study; Proceedings of the Workshop, Falmouth, Mass., September 8-11, 1975

    Science.gov (United States)

    Svestka, Z.

    1976-01-01

    The papers deal with problems which might be common to solar flares and earth's magnetosphere, problems associated with the initial phases of the flare phenomenon, the acceleration processes that seem to occur in flares and the magnetosphere, as well as the buildup and storage of flare energy in magnetic-field structures. Topics include the active role of magnetic fields in providing flare energy, current-sheet models of solar flares, the role of plasma turbulence in flare development, similarities and differences between magnetospheric substorms and solar flares, observations of magnetic merging in earth's magnetotail during magnetospheric substorms, evidence for magnetic-energy storage in coronal active regions, the possible role of transition-zone instabilities in preflare energy buildup, and flare energy storage and deposition. Other papers discuss energy release through the interaction of coronal magnetic fields, photospheric electric currents as a source of flare energy, magnetic-energy buildup in the solar atmosphere, magnetic and velocity fields in an active region, flare onset at meter wavelengths, laboratory experiments on field-line reconnection, key problems in auroral flare processes, and the solar-physics Shuttle/Spacelab program. Individual items are announced in this issue.

  4. Gamma-ray dose at shield-tissue interfaces and buildup factor implications

    International Nuclear Information System (INIS)

    Buildup factors continue to be widely used for gamma-ray shield design, but there are several problems in application. Shure has pointed out the need for buildup factors to be consistent with the ANSI standard flux-to-dose factors. However, consistent buildup factor data cannot be obtained by simply integrating the ANSI response function over infinite-medium spectra, because this function gives the response at various depths in a tissue phantom for a gamma ray of a certain energy entering the phantom. The ANSI response function can only be applied to a spectrum emerging from a shield as determined from a transport calculation. In order to evaluate the dose in tissue from gamma rays which have penetrated a shield, a detailed transport study was undertaken at the Safety Research Laboratory at Kalpakkam in collaboration with the Radiation shielding Information Center. Computations were made using the one-dimensional transport code ASFIT which has recently been extended to treat the secondary sources of fluorescence and bremsstrahlung. Results are reported

  5. On spatial stabilization of dielectric barrier discharge microfilaments by residual heat build-up in air

    Science.gov (United States)

    Ráhel, Jozef; Szalay, Zsolt; Čech, Jan; Morávek, Tomás

    2016-04-01

    Microfilaments of dielectric barrier discharge are known for their multiple re-appearance at the same spot on dielectrics. This effect of localized re-appearance is driven by residual excited species and ions, surface charge deposited on the dielectric and the local temperature build-up resulting in the local increase of reduced electric field E/ΔN. To assess the magnitude of the latter, the breakdown voltage vs. temperature up to 180 °C was carefully measured at coplanar DBD and used as an input into the numerical simulation of heat build-up by the train of discharge pulses. An average reduction of breakdown voltage was found to be 20 V/K. The model predicted a quasi-stable microfilament temperature into which the thermal build-up rapidly converges. Its magnitude agreed well with the reported rotational temperature of similar electrode configuration. The impact of quasi-stable temperature on microfilament formation dynamics is further discussed. Contribution to the Topical Issue "Recent Breakthroughs in Microplasma Science and Technology", edited by Kurt Becker, Jose Lopez, David Staack, Klaus-Dieter Weltmann and Wei Dong Zhu.

  6. Optimal Thermo-Structural Analysis for High Density Package Mounting on Build-up Board

    Science.gov (United States)

    Nakanishi, Tohru; Hase, Tomohiro

    The importance of the high density packaging technology and mounting technology on the printed wiring build-up board has been increased for the consumer electric products. On the other hand, the chance to use the build-up boards for mounting the high density packages has been increased. However, the understanding that the reliability of the solder connection depends on the structure of the package, the motherboard, and the material properties, is not very high. In this paper, the reliability for high density packaging, mounted on the build-up board, is assessed. The compact numerical analysis model for the reliability assessment is suggested and the most reliable packaging design with optimizing each of the parameters is reported. For introduction to the reliability assessment of the FCA attachment, ceramic and silicon are compared as the inter-poser with the parameter of the solder height. The verification of the numerical analysis results using tests on the actual hardware is also shown. And the established numerical analysis model is applied to the study of influence of the copper balance between the front side and the back side copper layers.

  7. Pressure Buildup Analysis for Two-Phase Geothermal Wells: Application to the Baca Geothermal Field

    Science.gov (United States)

    Riney, T. D.; Garg, S. K.

    1985-03-01

    The recently published pressure transient analysis methods for two-phase geothermal wells are employed to analyze the pressure buildup data for several wells located in the Redondo Creek area of the Baca geothermal field in New Mexico. The downhole drilling information and pressure/temperature surveys are first interpreted to locate zones at which fluid enters the well bore from the formation and to estimate the initial reservoir temperature and pressure in these zones. All of the Baca wells considered here induced flashing in the formation upon production. Interpretation of the buildup data for each well considers well bore effects (e.g., phase change in the well bore fluid and location of the pressure sensor with respect to the permeable horizon) and the carbon dioxide content of the fluid and its effects on the phase behavior of the reservoir fluids and differentiates between the single- and two-phase portions of the pressure buildup data. Different straight-line approximations to the two portions (i.e., single- and two-phase) of the data on the Homer plot are used to obtain corresponding estimates for the single- and two-phase mobilities. Estimates for the formation permeability-thickness (kH) product are also given.

  8. Monitoring the progress of build-up formation in fatty alcohol plant pipelines using gamma-ray scanning techniques

    International Nuclear Information System (INIS)

    A study was conducted to monitor the progress of material build-up formation in fatty acid alcohol pipelines using gamma ray absorption techniques. The investigation was periodically performed at few selected location which has been defined as critical area. Before performing a scan, the intensity of the gamma ray as a reference at the clean pipe should be determined. From the gamma ray absorption principle, the intensity of the radiation initial and the radiation after it pass through a material should be different, so the thickness of the build-up in the pipeline can be determined. As a result, base on this early information of the actual condition of the build-up formation, the more effective maintenance schedule can be planned. From that, the maintenance cost which is due to the build-up formation could be minimise as low as possible. (Author)

  9. Gamma Ray Buildup Factor for Finite Media in Energy Range (4-10) MeV for Al and Pb

    International Nuclear Information System (INIS)

    A computer program based on Monte Carlo method had been designed and written in visual basic computer language and utilized for simulating the classic problem of gamma ray beam incident on finite plane slabs of absorbing materials.The source geometry adopted in this program is plane normal source. Dose buildup factor of gamma photons in the absence and presence pair production effect have been calculated in the energy range (4-10) MeV for Aluminum and Lead up to 5 mean free path thickness.Dose buildup factor in the presence of pair production is higher than dose buildup factor in the absence of pair production effect.The deviation between the values of dose buildup factor in the presence and absence pair production is increased when the energy is increased within the studied energy range because the cross section for pair production is increased within the studied energy range

  10. Assessment of exposure buildup factors of some oxide dispersion strengthened steels applied in modern nuclear engineering and designs

    International Nuclear Information System (INIS)

    Highlights: • We report new data on energy absorption and exposure buildup factor for some oxide dispersion strengthened steels. • The GP fitting method can be used to calculate buildup factors up to 40 mfp. • These parameters are useful in reactor and to its structural shielding materials. - Abstract: The gamma-ray exposure buildup factors of oxide dispersive-strengthen (ODS) steel alloys have been computed for photon energy 0.015–15 MeV up to 40 mean free path (mfp) penetration depth by geometrical progression (GP) method. An appreciable variation in exposure buildup factors for the investigated ODS steel alloys was observed. The exposure buildup factors of ODS alloys were observed strongly depending upon the photon energy, penetration depths and the chemical compositions. The exposure buildup factors were found to be small in low- and high-photon energy whereas these were very large in intermediate-energy region. Our investigation signifies that the Eurofer 97 ODS steel alloy is the superior gamma-ray and neutron shielding materials. This study should be useful for shielding design and application in future reactor technologies and fusion reactor blankets

  11. Influence of iron and nickel species upon activity buildup under simulated BWR conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bjornsson, S.; Chen, J. [Studsvik Nuclear AB, Nykoping (Sweden); Lejon, J. [OKG AB, Oskarshamn (Sweden); Granath, G. [Ringhals AB, Varobacka (Sweden); Tanse-Larsson, M. [Forsmarks Kraftgrupp AB, Osthammar (Sweden)

    2010-07-01

    Activity build-up in BWR systems are of importance for service- and maintenance work performed at the plants. Minimizing the activity build-up is desirable for minimizing doses of personnel at the plants. Numerous studies have been carried out in this important field to understand the activity uptake mechanisms. This paper studied the possible role of Fe(II/III) and Ni(II) impurities in reactor water in activity uptake on stainless steel surfaces. The study was carried out by using a test loop with simulated BWR water containing Fe(II/III), Ni(II) and Co-60 marked Co(II) species of varied concentration and 500 ppb O{sub 2}. The test tube section in the loop system was pre-exposed type 316L stainless steel material. The microstructures of the formed oxide films were examined with high resolution electron microscopy (FE-SEM and FE-TEM). The activity monitoring on the test section showed that injection of 10 ppb Ni(II) and 0.1 ppb Fe(II/III) in the water with 0.1 ppb Co(II) was capable of stopping completely activity uptake. When Co(II) addition in the loop was stopped no activity return to the water could be seen. In another exposure test, injection of combined 2 ppb Fe(II/III) and 0.5∼10 ppb Ni(II) profoundly increased activity uptake on the test section with a maximum in activity buildup at 5 ppb Ni(II). When Co(II) addition in the loop was stopped a slight activity return was seen. The observed differences as seen in the two tests are discussed in view of the microstructures of the oxide films formed. (author)

  12. Build-up material requirements in clinical dosimetry during total body irradiation treatments.

    Science.gov (United States)

    Butson, Martin; Pope, Dane; Haque, Mamoon; Chen, Tom; Song, Guangli; Whitaker, May

    2016-01-01

    Total body irradiation (TBI) treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow) transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD). This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83-90% (93-97% at 1 mm depth), depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm(2). As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications.

  13. Build-up material requirements in clinical dosimetry during total body irradiation treatments.

    Science.gov (United States)

    Butson, Martin; Pope, Dane; Haque, Mamoon; Chen, Tom; Song, Guangli; Whitaker, May

    2016-01-01

    Total body irradiation (TBI) treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow) transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD). This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83-90% (93-97% at 1 mm depth), depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm(2). As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications. PMID:27217628

  14. Photon buildup factors in some dosimetric materials for heterogeneous radiation sources.

    Science.gov (United States)

    Kurudirek, Murat

    2014-03-01

    Effective photon energy absorption (EABF(eff)) and exposure buildup factors (EBF(eff)) have been calculated based on the effective energy concept, for some dosimetric materials such as water, polymethyl methacrylate (PMMA), polystyrene, solid water (WT1), RW3 (Goettingen Water 3), and ABS (acrylonitrile butadiene styrene), for MV X-rays and (60)Co gamma rays. Firstly, the equivalent atomic numbers (Z(eq)) of the given materials have been determined using the effective photon energies (E eff). Then, the five-parameter geometric progression (G-P) fitting approximation has been used to calculate both EABF(eff) and EBF(eff) values. Since the G-P fitting parameters are not available for the E eff values of the given materials, a linear interpolation in which a function of the logarithm of the variable is used has been performed, in order to calculate the parameters in each E eff, which will be further used for the determination of EABF(eff) and EBF(eff). In the present paper, water equivalence properties of the given materials are also discussed based on the effective buildup factors. In this study, special emphasis is placed on the calculation of EABF(eff) and EBF(eff) values of different materials for photons that are not monoenergetic but heterogeneous in energy, to obtain an initial and prior knowledge of the probable energy and buildup of photons at locations of interest, i.e., to understand whether the real absorbed dose occurs at the surface or somewhere inside the medium of interest. PMID:24287785

  15. Rime Mushrooms - Extreme Rime Ice Buildup on Mountain Summits of Southern Patagonia

    Science.gov (United States)

    Whiteman, C. D.

    2015-12-01

    The Southern Patagonian Andes are known among mountain climbers for a meteorological phenomenon that occurs there but is unknown in many other mountain areas. The phenomenon is the buildup of rime ice in large bulbous or mushroom-shaped accretions on the windward side of projecting mountain summits, ridges and exposed near-vertical rock faces. These "ice mushrooms" have never been investigated scientifically. This talk will introduce the audience to ice mushrooms, describe where they are found, consider the meteorological factors leading to their formation, and illustrate how they are negotiated by mountain climbers using photographs and descriptions from Southern Patagonia.

  16. Time-Scales for Non-Inductive Current Buildup in Low-Aspect-Ratio Toroidal Geometry

    International Nuclear Information System (INIS)

    The fundamental differences between inductive and non-inductive current buildup are clarified and the associated time-scales and other implications are discussed. A simulation is presented whereby the plasma current in a low-aspect-ratio torus is increased primarily by the self-generated bootstrap current with only 10% coming from external current drive. The maximum obtainable plasma current by this process is shown to scale with the toroidal field strength. The basic physics setting the time-scales can be obtained from a 1D analysis. Comparisons are made between the timescales found here and those reported in the experimental literature

  17. Simulations of electron cloud build-up and saturation in the APS

    International Nuclear Information System (INIS)

    In studies with positron beams in the Advanced Photon Source, a dramatic amplification was observed in the electron cloud for certain bunch current and bunch spacings. In modeling presented previously, we found qualitative agreement with the observed beam-induced multipacting condition, provided reasonable values were chosen for the secondary electron yield parameters, including the energy distribution. In this paper, we model and discuss the build-up and saturation process observed over long bunch trains at the resonance condition. Understanding this saturation mechanism in more detail may have implications for predicting electron cloud amplification, multipacting, and instabilities in future rings

  18. The role of the buildup oscillations on the speed of resonant tunneling diodes

    CERN Document Server

    Romo, R; Romo, Roberto; Villavicencio, Jorge

    2001-01-01

    The fastest tunneling response in double barrier resonant structures is investigated by considering explicit analytic solutions of the time dependent Schr\\"{o}dinger equation. For cutoff initial plane waves, we find that the earliest tunneling events consist on the emission of a series of propagating pulses of the probability density governed by the buildup oscillations in the quantum well. We show that the fastest tunneling response comes from the contribution of incident carriers at energies different from resonance, and that its relevant time scale is given by $\\tau_r=\\pi \\hbar /| E-\\epsilon | $, where $\\epsilon $ is the resonance energy and $E$ is the incidence energy.

  19. Energy-dependent finite-orbit treatment for plasma buildup in mirror fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, M.M.

    1980-01-01

    A computer simulation of hot plasma buildup in mirror fusion devices and results from this model are presented. In a small, hot magnetically confined plasma, the ion orbit radius (rho/sub i/) can be comparable to the plasma radius (R/sub p/). It a mirror-confined plasma were rho/sub i//R/sub p/ > 1/25 (such as 2XII-B), a point kinetic treatment of ion interactions becomes inaccurate and a finite gyro-radius (FGR) treatment must be used to adequately describe plasma buildup processes. This is particularly true for describing losses due to cold-gas charge exchange (c-x) near the plasma surface, since a particle lost near the vacuum interface may have contributed to the density as far as 2 rho/sub i/ radially inward from the c-x point. A similar FGR effect applies to beam-deposited ions whose large orbits influence the density up to 2 rho/sub i/ from the trapping point.

  20. Simulation on buildup of electron cloud in a proton circular accelerator

    Science.gov (United States)

    Li, Kai-Wei; Liu, Yu-Dong

    2015-10-01

    Electron cloud interaction with high energy positive beams are believed responsible for various undesirable effects such as vacuum degradation, collective beam instability and even beam loss in high power proton circular accelerators. An important uncertainty in predicting electron cloud instability lies in the detailed processes of the generation and accumulation of the electron cloud. The simulation on the build-up of electron cloud is necessary to further studies on beam instability caused by electron clouds. The China Spallation Neutron Source (CSNS) is an intense proton accelerator facility now being built, whose accelerator complex includes two main parts: an H-linac and a rapid cycling synchrotron (RCS). The RCS accumulates the 80 MeV proton beam and accelerates it to 1.6 GeV with a repetition rate of 25 Hz. During beam injection with lower energy, the emerging electron cloud may cause serious instability and beam loss on the vacuum pipe. A simulation code has been developed to simulate the build-up, distribution and density of electron cloud in CSNS/RCS. Supported by National Natural Science Foundation of China (11275221, 11175193)

  1. Radiation-field buildup at Monticello BWR with hydrogen water chemistry

    International Nuclear Information System (INIS)

    Primary recirculation piping at Monticello Nuclear Generating Plant was replaced in 1984. In November 1988, approximately midway through the third fuel cycle after pipe replacement, Monticello initiated hydrogen addition to mitigate the possibility of stress corrosion cracking. Due to expectedly high activity levels of Cobalt-60 observed in April of 1989, Northern States Power elected to decontaminate the entire primary system during the August 1989 refueling outage at the end of the third fuel cycle after pipe replacement. At the beginning of the fourth fuel cycle after pipe replacement, Monticello also initiated GEZIP in an effort to reduce future radiation level build-up. Four isotopic measurement campaigns of the Monticello recirculation system were performed since the system was decontaminated in 1989. These measurement campaigns and the radiation build-up at MNGP during fuel cycle 14 are the subject of this report. Northern States Power Company also performed a primary system decontamination at the end of cycle 14. the decontamination process was also monitored and the final report documenting these measurements, RCT-9107-2403, is appended to this report. 4 refs., 3 figs., 9 tabs

  2. Hizbollah’s Force Buildup of 2006-2009: Foundations and Future Trends

    Directory of Open Access Journals (Sweden)

    Guy Aviad

    2009-12-01

    Full Text Available On August 12, 2006, the UN Security Council adopted Resolution 1701, paving the way for the end of 34 days of warfare between Israel and Hizbollah, a campaign later named the Second Lebanon War. Apart from the immediate need to establish a ceasefire, the Security Council hoped to change the security reality in southern Lebanon while neutralizing the elements that were responsible for the escalation, and prevent the repetition of another round of fighting between the sides. Resolution 1701 ostensibly gave an adequate response to Israel’s security needs on the Lebanese front and significantly limited Hizbollah’s ability to rearm in southern Lebanon. The purpose of this essay is to examine Hizbollah’s renewed force buildup since the end of the war in August 2006 despite the constraints of Resolution 1701, to understand the foundations underlying the rearmament of the last three years, and on the basis of this analysis to infer future trends in the organization’s operational doctrine and the operative logic behind the trends. The essay analyzes a number of aspects of Hizbollah’s force buildup, such as manpower, armaments, training, and deployment in the arena, in context of the lessons the organization learned from its various successes and failures in the war. The essay also examines the extent to which these conclusions match the organization’s plan for confrontation against the IDF in the next round.

  3. Electron Cloud Buildup Characterization Using Shielded Pickup Measurements and Custom Modeling Code at CESRTA

    CERN Document Server

    Crittenden, James A

    2013-01-01

    The Cornell Electron Storage Ring Test Accelerator experimental program includes investigations into electron cloud buildup, applying various mitigation techniques in custom vacuum chambers. Among these are two 1.1-m-long sections located symmetrically in the east and west arc regions. These chambers are equipped with pickup detectors shielded against the direct beam-induced signal. They detect cloud electrons migrating through an 18-mm-diameter pattern of small holes in the top of the chamber. A digitizing oscilloscope is used to record the signals, providing time-resolved information on cloud development. Carbon-coated, TiN-coated and uncoated aluminum chambers have been tested. Electron and positron beams of 2.1, 4.0 and 5.3 GeV with a variety of bunch populations and spacings in steps of 4 and 14 ns have been used. Here we report on results from the ECLOUD modeling code which highlight the sensitivity of these measurements to the physical phenomena determining cloud buildup such as the photoelectron produ...

  4. Optical fiber sensors and their application in monitoring stress build-up in dental resin cements

    Science.gov (United States)

    Ottevaere, H.; Tabak, M.; Fernandez Fernandez, A.; Berghmans, F.; Thienpont, H.

    2005-09-01

    The field of optical fiber sensing is highly diverse and this diversity is perceived as a great advantage over more conventional sensors in that an optical sensor can be tailored to measure any of a myriad of physical parameters. In this paper we present a niche application for optical fiber sensors in the domain of biophotonics, namely the monitoring of stress build-up during the curing process of dental resin cements. We discuss the origin of this stress build-up and the problems it can cause when treating patients. Optical fiber sensors aim at excelling in two kind of applications: firstly to perform quality control on batch produced dental cements and measure their total material shrinkage, secondly to monitor the hardening of the cement during in-vivo measurements resulting in the dynamic measurement of the shrinkage and to control the stress in a facing based restoration. We therefore investigated two types of optical fiber sensors as alternatives to conventional measurement techniques; namely polarimetric optical fiber sensors and fiber Bragg gratings written in polarization maintaining fibers. After discussing the results obtained with both optical fiber sensors, we will conclude with a critical assessment of the suitability of the two proposed sensing configurations for multi-parameter stress monitoring.

  5. Investigation of Pectin/Chitosan Multilayers Build-up on Corona Charged Polylactide Substrates

    Science.gov (United States)

    Yovcheva, T. A.; Marudova, M. G.; Viraneva, A. P.; Gencheva, E. A.; Mekishev, G. A.; Sainov, S. H.

    2010-01-01

    The aim of the present research is to investigate the formation and stability of pectin/chitosan multilayer films on preliminary corona charged polylactide substrate with different polarity. For this purpose two different multilayer structures with alternative ordering of polycation and polyanion layers were prepared. Layer-by-layer (LbL) deposition technique was used for multilayer build-up. The FT-IR transmittance spectra of the substrates with multilayers indicated of the presence of pectin and chitosan. The intensity of the typical bands was found to increase with increasing of the number of the deposited layers. The stability and physico-chemical properties of the multilayer structures were investigated by determination of surface refractive index and swelling behaviour. Multilayers are stable enough in distilled water and their equilibrium degree of swelling increases with the increase of build-up layers. This relation is correlated with the increased amount of hydrophilic biopolymers. It was found out that chitosan/pectin multilayers buil-up on negatively charged substrate consist of higher amount of polyelectrolytes and are more stable in distilled water.

  6. Prediction model of the buildup of volatile organic compounds on urban roads.

    Science.gov (United States)

    Mahbub, Parvez; Goonetilleke, Ashantha; Ayoko, Godwin A

    2011-05-15

    A model to predict the buildup of mainly traffic-generated volatile organic compounds or VOCs (toluene, ethylbenzene, ortho-xylene, meta-xylene, and para-xylene) on urban road surfaces is presented. The model required three traffic parameters, namely average daily traffic (ADT), volume to capacity ratio (V/C), and surface texture depth (STD), and two chemical parameters, namely total suspended solid (TSS) and total organic carbon (TOC), as predictor variables. Principal component analysis and two phase factor analysis were performed to characterize the model calibration parameters. Traffic congestion was found to be the underlying cause of traffic-related VOC buildup on urban roads. The model calibration was optimized using orthogonal experimental design. Partial least squares regression was used for model prediction. It was found that a better optimized orthogonal design could be achieved by including the latent factors of the data matrix into the design. The model performed fairly accurately for three different land uses as well as five different particle size fractions. The relative prediction errors were 10-40% for the different size fractions and 28-40% for the different land uses while the coefficients of variation of the predicted intersite VOC concentrations were in the range of 25-45% for the different size fractions. Considering the sizes of the data matrices, these coefficients of variation were within the acceptable interlaboratory range for analytes at ppb concentration levels.

  7. The future role of reforestation in reducing buildup of atmospheric CO2

    International Nuclear Information System (INIS)

    Among the options posed for mitigating the buildup of atmospheric CO2 is planting new forest areas to sequester carbon from the atmosphere. Among the questions of interest in modeling the global carbon cycle is the extent to which reforestation is likely to succeed in providing physical removal of CO2 from the atmosphere. There are many strategies for using forest land to mitigate the atmospheric buildup of CO2: decreasing the rate at which forests are cleared for other land uses, increasing the density of carbon storage in existing forests, improving the rate and efficiency at which forest products are used in the place of other energy intensive products, substitution of renewable wood fuels for fossil fuels, improved management of forests and agroforestry, and increasing the amount of land in standing forest. Because increasing the area of forests has social, political, and economic limitations; in addition to physical limitations; it is hard to envision a large increase in forest area except where there are associated economic benefits. The authors speculation is that, over the next several decades, the forest strategies most likely to be pursued for the express purpose of CO2 mitigation are those which provide more or more-efficient substitution of forest products for energy or energy-intensive resources and that the physical accumulation of additional carbon in forests will be of lesser importance

  8. Impact of eccentricity build-up and graveyard disposal Strategies on MEO navigation constellations

    Science.gov (United States)

    Radtke, Jonas; Domínguez-González, Raúl; Flegel, Sven K.; Sánchez-Ortiz, Noelia; Merz, Klaus

    2015-12-01

    With currently two constellations being in or close to the build-up phase, in a few years the Medium Earth Orbit (MEO) region will be populated with four complete navigation systems in relatively close orbital altitudes: The American GPS, Russian GLONASS, European Galileo, and Chinese BeiDou. To guarantee an appropriate visibility of constellation satellites from Earth, these constellations rely on certain defined orbits. For this, both the repeat pattern, which is basically defined by the semimajor axis and inclination, as well as the orbital planes, which are defined by the right ascension of ascending node, are determining values. To avoid an overcrowding of the region of interest, the disposal of satellites after their end-of-life is recommended. However, for the MEO region, no internationally agreed mitigation guidelines exist. Because of their distances to Earth, ordinary disposal manoeuvres leading to a direct or delayed re-entry due to atmospheric drag are not feasible: The needed fuel masses for such manoeuvres are by far above the reasonable limits and available fuel budgets. Thus, additional approaches have to be applied. For this, in general two options exist: disposal to graveyard orbits or the disposal to eccentricity build-up orbits. In the study performed, the key criterion for the graveyard strategy is that the disposed spacecraft must keep a safe minimum distance to the altitude of the active constellation on a long-term time scale of up to 200 years. This constraint imposes stringent requirements on the stability of the graveyard orbit. Similar disposals are also performed for high LEO satellites and disposed GEO payloads. The eccentricity build-up strategy on the other hand uses resonant effects between the Earth's geopotential, the Sun and the Moon. Depending on the initial conditions, these can cause a large eccentricity build-up, which finally can lead to a re-entry of the satellite. In this paper, the effects of applying either the first or

  9. Evaluation of simplified analytical models for CO2 plume movement and pressure buildup

    Science.gov (United States)

    Oruganti, Y.; Mishra, S.

    2011-12-01

    CO2 injection into the sub-surface is emerging as a viable technology for reducing anthropogenic CO2 emissions into the atmosphere. When large amounts of CO2 are sequestered, pressure buildup is an associated risk, along with plume movement beyond the injected domain. In this context, simple modeling tools become valuable assets in preliminary CO2 injection project screening and implementation phases. This study presents an evaluation of two commonly used simplified analytical models for plume movement and pressure buildup, (1) the sharp interface model of Nordbotten et al. (2005), and the corresponding pressure distribution solution of Mathias et al. (2008), and (2) the 3-region model of Burton et al. (2008) based on fractional flow and steady-state pressure gradient considerations. The three-region model of Burton et al. assumes a constant pressure outer boundary. In this study, we incorporate the radius of investigation of the pressure front as the transient pressure boundary, in order to represent an infinite-acting system. The sharp-interface model also assumes the system to be infinite-acting. Temperature and pressure conditions used in these models correspond to the "warm, shallow" and "cold, deep" aquifer conditions as defined by Nordbotten et al. The saturation and pressure profiles as well as injection-well pressure buildup predicted by the analytical models are compared with those from the numerical simulator STOMP in order to provide a verification of the simplified modeling assumptions. Both the STOMP results and the three-region model show two sharp fronts (the drying and two-phase fronts), and a good match is obtained between the front positions at any time. For the sharp interface model, the vertically averaged gas saturation does not exhibit two sharp fronts as seen in the STOMP simulations, but shows a gradual change in saturation with radial distance over the two-phase region. The pressure profiles from STOMP and the analytical model are

  10. Differential aquaporin 4 expression during edema build-up and resolution phases of brain inflammation

    Directory of Open Access Journals (Sweden)

    Brochet Bruno

    2011-10-01

    Full Text Available Abstract Background Vasogenic edema dynamically accumulates in many brain disorders associated with brain inflammation, with the critical step of edema exacerbation feared in patient care. Water entrance through blood-brain barrier (BBB opening is thought to have a role in edema formation. Nevertheless, the mechanisms of edema resolution remain poorly understood. Because the water channel aquaporin 4 (AQP4 provides an important route for vasogenic edema resolution, we studied the time course of AQP4 expression to better understand its potential effect in countering the exacerbation of vasogenic edema. Methods Focal inflammation was induced in the rat brain by a lysolecithin injection and was evaluated at 1, 3, 7, 14 and 20 days using a combination of in vivo MRI with apparent diffusion coefficient (ADC measurements used as a marker of water content, and molecular and histological approaches for the quantification of AQP4 expression. Markers of active inflammation (macrophages, BBB permeability, and interleukin-1β and markers of scarring (gliosis were also quantified. Results This animal model of brain inflammation demonstrated two phases of edema development: an initial edema build-up phase during active inflammation that peaked after 3 days (ADC increase was followed by an edema resolution phase that lasted from 7 to 20 days post injection (ADC decrease and was accompanied by glial scar formation. A moderate upregulation in AQP4 was observed during the build-up phase, but a much stronger transcriptional and translational level of AQP4 expression was observed during the secondary edema resolution phase. Conclusions We conclude that a time lag in AQP4 expression occurs such that the more significant upregulation was achieved only after a delay period. This change in AQP4 expression appears to act as an important determinant in the exacerbation of edema, considering that AQP4 expression is insufficient to counter the water influx during the build-up

  11. The effect of plasma minor-radius expansion in the current build-up phase of a large tokamak

    International Nuclear Information System (INIS)

    A plasma simulation code has been developed to study the plasma current build-up process in JT-60. Plasma simulation is made with a model which represents well overall plasma behavior of the present-day tokamaks. The external electric circuit is taken into consideration in simulation calculation. An emphasis is placed on the simulation of minor-radius expansion of the plasma and behavior of neutral particles in the plasma during current build-up. A calculation with typical parameters of JT-60 shows a week skin distribution in the current density and the electron temperature, if the minor radius of the plasma expands with build-up of the plasma current. (auth.)

  12. Energy absorption buildup factors of human organs and tissues at energies and penetration depths relevant for radiotherapy and diagnostics

    DEFF Research Database (Denmark)

    Manohara, S. R.; Hanagodimath, S. M.; Gerward, Leif

    2011-01-01

    Energy absorption geometric progression (GP) fitting parameters and the corresponding buildup factors have been computed for human organs and tissues, such as adipose tissue, blood (whole), cortical bone, brain (grey/white matter), breast tissue, eye lens, lung tissue, skeletal muscle, ovary...... for skeletal muscle, adipose tissue, cortical bone, and lung tissue are also discussed. It is observed that water and MS20 are good tissue equivalent materials for skeletal muscle in the extended energy range......., testis, soft tissue, and soft tissue (4-component), for the photon energy range 0.015-15 MeV and for penetration depths up to 40 mfp (mean free path). The chemical composition of human organs and tissues is seen to influence the energy absorption buildup factors. It is also found that the buildup factor...

  13. Numerical simulation of flare energy build-up and release via Joule dissipation. [solar MHD model

    Science.gov (United States)

    Wu, S. T.; Bao, J. J.; Wang, J. F.

    1986-01-01

    A new numerical MHD model is developed to study the evolution of an active region due to photospheric converging motion, which leads to magnetic-energy buildup in the form of electric current. Because this new MHD model has incorporated finite conductivity, the energy conversion occurs from magnetic mode to thermal mode through Joule dissipation. In order to test the causality relationship between the occurrence of flare and photospheric motion, a multiple-pole configuration with neutral point is used. Using these results it is found that in addition to the converging motion, the initial magnetic-field configuration and the redistribution of the magnetic flux at photospheric level enhance the possibility for the development of a flare.

  14. The Accelerated Build-up of the Red Sequence in High Redshift Galaxy Clusters

    CERN Document Server

    Cerulo, P; Lidman, C; Demarco, R; Huertas-Company, M; Mei, S; Sánchez-Janssen, R; Barrientos, L F; Muñoz, R P

    2016-01-01

    We analyse the evolution of the red sequence in a sample of galaxy clusters at redshifts $0.8 11.5$) red sequence galaxies in the WINGS clusters, which do not include only the brightest cluster galaxies and which are not present in the HCS clusters, suggesting that they formed at epochs later than $z=0.8$. The comparison with the luminosity distribution of a sample of passive red sequence galaxies drawn from the COSMOS/UltraVISTA field in the photometric redshift range $0.8build-up of the red sequence.

  15. Model Study of the Pressure Build-Up during Subcutaneous Injection

    DEFF Research Database (Denmark)

    Thomsen, Maria; Hernandez Garcia, Anier; Mathiesen, Joachim;

    2014-01-01

    of a porous medium. For equivalent injection forces we measure the change in the infusion rate between injections in air at atmospheric pressure and in tissue. From a best fit with our model, we then determine the flow permeability as well as the bulk modulus of the tissue, estimated to be of the order 10......In this study we estimate the subcutaneous tissue counter pressure during drug infusion from a series of injections of insulin in type 2 diabetic patients using a non-invasive method. We construct a model for the pressure evolution in subcutaneous tissue based on mass continuity and the flow laws......-11-10-10 m2 and 105 Pa, respectively. The permeability is in good agreement with reported values for adipose porcine tissue. We suggest our model as a general way to estimate the pressure build-up in tissue during subcutaneous injection....

  16. Natural refuge crops, buildup of resistance, and zero-refuge strategy for Bt cotton in China

    Institute of Scientific and Technical Information of China (English)

    ROZELLE; Scott; WILEN; James

    2010-01-01

    In the context of genetically modified crops expressing the Bacillus thuringiensis (Bt) toxin, a ‘refuge’ refers to a crop of the same or a related species that is planted nearby to enable growth and reproduction of the target pest without the selection pres- sure imposed by the Bt toxin. The goal of this study is to discuss the role of natural refuge crops in slowing down the buildup of resistance of cotton bollworm (CBW), and to evaluate China’s no-refuge policy for Bt cotton. We describe in detail the dif- ferent factors that China should consider in relation to the refuge policy. Drawing on a review of scientific data, economic analyses of other cases, and a simulation exercise using a bio-economic model, we show that in the case of Bt cotton in China, the no-refuge policy is defensible.

  17. Build-up and decline of organic matter during PeECE III

    Directory of Open Access Journals (Sweden)

    K. G. Schulz

    2007-11-01

    Full Text Available Increasing atmospheric carbon dioxide (CO2 concentrations due to anthropogenic fossil fuel combustion currently change the ocean's chemistry. Increasing oceanic [CO2] and subsequent decreasing seawater pH have the potential to significantly impact marine life. Here we describe and analyze the build-up and decline of a natural phytoplankton bloom initiated during the 2005 mesocosm Pelagic Ecosystem CO2 Enrichment study (PeECE III. We show that processes of inorganic carbon uptake in mixed surface waters and organic carbon export to depth were significantly enhanced at elevated CO2, while ammonium regeneration in deep waters was substantially reduced. This has important implications for our understanding of pelagic ecosystem functioning and future carbon cycling.

  18. Resonant laser power build-up in ALPS - a "light-shining-through-walls" experiment -

    CERN Document Server

    Ehret, Klaus; Ghazaryan, Samvel; Hildebrandt, Matthias; Knabbe, Ernst-Axel; Kracht, Dietmar; Lindner, Axel; List, Jenny; Meier, Tobias; Meyer, Niels; Notz, D; Redondo, Javier; Ringwald, Andreas; Wiedemann, Günter; Willke, Benno

    2009-01-01

    The ALPS collaboration runs a light-shining-through-walls (LSW) experiment to search for photon oscillations into "weakly interacting sub-eV particles" (WISPs) inside of a superconducting HERA dipole magnet at the site of DESY. In this paper we report on the first successful integration of a large-scale optical cavity to boost the available power for WISP production in this type of experiments. The key elements are a frequency tunable narrow line-width continuous wave laser acting as the primary light source and an electronic feed-back control loop to stabilize the power build-up. We describe and characterize our apparatus and demonstrate the data analysis procedures on the basis of a brief exemplary run.

  19. Simulation of sulfide buildup in wastewater and atmosphere of sewer networks.

    Science.gov (United States)

    Nielsen, A H; Yongsiri, C; Hvitved-Jacobsen, T; Vollertsen, J

    2005-01-01

    A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.

  20. History of water loss and atmospheric O2 buildup on rocky exoplanets near M dwarfs

    Science.gov (United States)

    Tian, Feng

    2015-12-01

    It is recently proposed that early stellar luminosity evolution of M dwarfs leads to severe water loss and the buildup of massive O2 atmospheres on rocky exoplanets in the habitable zone of these stars if interactions of such O2 atmospheres with planetary surfaces are inefficient. Here we show that even without considering atmosphere-surface interactions, the existence of a massive O2 atmosphere on such exoplanets is not an unavoidable consequence around M0-M3 stars and depends on stellar XUV properties, the mass of the exoplanets, and most importantly the initial planetary water inventories. In the case of inefficient atmosphere-surface interactions, the distribution of atmospheric O2 contents on these exoplanets should be bi-modal and such a distribution could be verified by future surveys of rocky exoplanets.

  1. Comparison between the radial density buildup in the TARA plugs using hydrogen versus deuterium neutral beams

    International Nuclear Information System (INIS)

    The WOLF code is used to compare the beam divergences from a TARA source using hydrogen and deuterium. Factors which influence the divergence which are investigated are the electron temperature, initial ion energy, electrode positions and ion beam current density. The beam divergence for 20 keV hydrogen is found to be only 20% smaller than for 25 keV deuterium for the same electrode positions. Since the optimal positioning of the electrodes is found to be independent of mesh spacing, a large parameter study is undertaken using little computer time. A time-dependent radial Fokker-Planck code is next used to examine the radial density buildup in a plug of the TARA tandem mirror. For both hydrogen and deuterium neutral beams, the influences of beam positioning, current and energy, edge neutral pressure and assumed electron temperature are studied

  2. Resonant laser power build-up in ALPS. A 'light-shining-through-walls' experiment

    International Nuclear Information System (INIS)

    The ALPS collaboration runs a light-shining-through-walls (LSW) experiment to search for photon oscillations into weakly interacting sub-eV particles (WISPs) inside of a superconducting HERA dipole magnet at the site of DESY. In this paper we report on the first successful integration of a large-scale optical cavity to boost the available power for WISP production in this type of experiments. The key elements are a frequency tunable narrow line-width continuous wave laser acting as the primary light source and an electronic feed-back control loop to stabilize the power build-up. We describe and characterize our apparatus and demonstrate the data analysis procedures on the basis of a brief exemplary run. (orig.)

  3. Buildup of the Kondo effect from real-time effective action for the Anderson impurity model

    Science.gov (United States)

    Bock, Sebastian; Liluashvili, Alexander; Gasenzer, Thomas

    2016-07-01

    The nonequilibrium time evolution of a quantum dot is studied by means of dynamic equations for time-dependent Green's functions derived from a two-particle-irreducible (2PI) effective action for the Anderson impurity model. Coupling the dot between two leads at different voltages, the dynamics of the current through the dot is investigated. We show that the 2PI approach is capable of describing the dynamical buildup of the Kondo effect, which shows up as a sharp resonance in the spectral function, with a width exponentially suppressed in the electron self-coupling on the dot. An external voltage applied to the dot is found to deteriorate the Kondo effect at the hybridization scale. The dynamic equations are evaluated within different nonperturbative resummation schemes, within the direct, particle-particle, and particle-hole channels, as well as their combination, and the results compared with those from other methods.

  4. Effect of the calibration in water and the build-up cap on the Mg(Ar) ionization chamber measurements.

    Science.gov (United States)

    Koivunoro, H; Hyvönen, H; Uusi-Simola, J; Jokelainen, I; Kosunen, A; Kortesniemi, M; Seppälä, T; Auterinen, I; Savolainen, S

    2011-12-01

    Magnesium-walled argon gas flow ionization chamber (Mg(Ar)) is used for photon dose measurements in the epithermal neutron beam of FiR 1 reactor in Finland. In this study, the photon dose measurements were re-evaluated against calculations applying a new chamber calibration factor defined in water instead of in air. Also, effect of the build-up cap on the measurements was investigated. The new calibration factor provides improved agreement between measured and calculated photon dose. Use of the build-up cap does not affect the measured signal in water in neutron beam.

  5. Effect of the calibration in water and the build-up cap on the Mg(Ar) ionization chamber measurements

    Energy Technology Data Exchange (ETDEWEB)

    Koivunoro, H., E-mail: hanna.koivunoro@helsinki.fi [Boneca Corporation, FI-00290 Helsinki (Finland)] [Department of Physics, P.O.B. 64, FI-00014 University of Helsinki (Finland)] [Department of Oncology, Helsinki University Central Hospital, P.O.B. 180, 00029 HUS (Finland); Hyvoenen, H. [Boneca Corporation, FI-00290 Helsinki (Finland); Uusi-Simola, J. [HUS Helsinki Medical Imaging Center, University of Helsinki (Finland); Jokelainen, I.; Kosunen, A. [Radiation Metrology Laboratory, Radiation and Nuclear Safety Authority-STUK, FI-00881 (Finland); Kortesniemi, M. [HUS Helsinki Medical Imaging Center, University of Helsinki (Finland); Seppaelae, T. [Department of Oncology, Helsinki University Central Hospital, P.O.B. 180, 00029 HUS (Finland); Auterinen, I. [VTT Technical Research Centre of Finland, Espoo (Finland); Savolainen, S. [Department of Physics, P.O.B. 64, FI-00014 University of Helsinki (Finland)] [HUS Helsinki Medical Imaging Center, University of Helsinki (Finland)

    2011-12-15

    Magnesium-walled argon gas flow ionization chamber (Mg(Ar)) is used for photon dose measurements in the epithermal neutron beam of FiR 1 reactor in Finland. In this study, the photon dose measurements were re-evaluated against calculations applying a new chamber calibration factor defined in water instead of in air. Also, effect of the build-up cap on the measurements was investigated. The new calibration factor provides improved agreement between measured and calculated photon dose. Use of the build-up cap does not affect the measured signal in water in neutron beam.

  6. Study of Gamma Ray Exposure Buildup Factor for Some Ceramics with Photon Energy, Penetration Depth and Chemical Composition

    Directory of Open Access Journals (Sweden)

    Tejbir Singh

    2013-01-01

    Full Text Available Gamma ray exposure buildup factor for some ceramics such as boron nitride (BN, magnesium diboride (MgB2, silicon carbide (SiC, titanium carbide (TiC and ferrite (Fe3O4 has been computed using five parametric geometric progression (G.P. fitting method in the energy range of 0.015 to 15.0 MeV, up to the penetration of 40 mean free path (mfp. The variation of exposure buildup factors for all the selected ceramics with incident photon energy, penetration depth, and chemical composition has been studied.

  7. Energy absorption buildup factors of human organs and tissues at energies and penetration depths relevant for radiotherapy and diagnostics.

    Science.gov (United States)

    Manohara, S R; Hanagodimath, S M; Gerward, L

    2011-11-15

    Energy absorption geometric progression (GP) fitting parameters and the corresponding buildup factors have been computed for human organs and tissues, such as adipose tissue, blood (whole), cortical bone, brain (grey/white matter), breast tissue, eye lens, lung tissue, skeletal muscle, ovary, testis, soft tissue, and soft tissue (4-component), for the photon energy range 0.015-15 MeV and for penetration depths up to 40 mfp (mean free path). The chemical composition of human organs and tissues is seen to influence the energy absorption buildup factors. It is also found that the buildup factor of human organs and tissues changes significantly with the change of incident photon energy and effective atomic number, Z(eff). These changes are due to the dominance of different photon interaction processes in different energy regions and different chemical compositions of human organs and tissues. With the proper knowledge of buildup factors of human organs and tissues, energy absorption in the human body can be carefully controlled. The present results will help in estimating safe dose levels for radiotherapy patients and also useful in diagnostics and dosimetry. The tissue-equivalent materials for skeletal muscle, adipose tissue, cortical bone, and lung tissue are also discussed. It is observed that water and MS20 are good tissue equivalent materials for skeletal muscle in the extended energy range.

  8. 76 FR 7238 - Pipeline Safety: Dangers of Abnormal Snow and Ice Build-Up on Gas Distribution Systems

    Science.gov (United States)

    2011-02-09

    ... Build-Up on Gas Distribution Systems AGENCY: Pipeline and Hazardous Materials Safety Administration... owners and operators of petroleum gas and natural gas facilities of the need to take the appropriate steps to prevent damage to pipeline facilities from accumulated snow or ice. Past events on natural...

  9. Shielded button electrodes for time-resolved measurements of electron cloud buildup

    International Nuclear Information System (INIS)

    We report on the design, deployment and signal analysis for shielded button electrodes sensitive to electron cloud buildup at the Cornell Electron Storage Ring. These simple detectors, derived from a beam-position monitor electrode design, have provided detailed information on the physical processes underlying the local production and the lifetime of electron densities in the storage ring. Digitizing oscilloscopes are used to record electron fluxes incident on the vacuum chamber wall in 1024 time steps of 100 ps or more. The fine time steps provide a detailed characterization of the cloud, allowing the independent estimation of processes contributing on differing time scales and providing sensitivity to the characteristic kinetic energies of the electrons making up the cloud. By varying the spacing and population of electron and positron beam bunches, we map the time development of the various cloud production and re-absorption processes. The excellent reproducibility of the measurements also permits the measurement of long-term conditioning of vacuum chamber surfaces

  10. Comparative study of mechanical properties of direct core build-up materials

    Directory of Open Access Journals (Sweden)

    Girish Kumar

    2015-01-01

    Full Text Available Background and Objectives: The strength greatly influences the selection of core material because core must withstand forces due to mastication and para-function for many years. This study was conducted to evaluate certain mechanical properties of commonly used materials for direct core build-up, including visible light cured composite, polyacid modified composite, resin modified glass ionomer, high copper amalgam, and silver cermet cement. Materials and Methods: All the materials were manipulated according to the manufacturer′s recommendations and standard test specimens were prepared. A universal testing machine at different cross-head speed was used to determine all the four mechanical properties. Mean compressive strength, diametral tensile strength, flexural strength, and elastic modulus with standard deviations were calculated. Multiple comparisons of the materials were also done. Results: Considerable differences in compressive strength, diametral tensile strength, and flexural strength were observed. Visible light cured composite showed relatively high compressive strength, diametral tensile strength, and flexural strength compared with the other tested materials. Amalgam showed the highest value for elastic modulus. Silver cermet showed less value for all the properties except for elastic modulus. Conclusions: Strength is one of the most important criteria for selection of a core material. Stronger materials better resist deformation and fracture provide more equitable stress distribution, greater stability, and greater probability of clinical success.

  11. An automated classification approach to ranking photospheric proxies of magnetic energy build-up

    CERN Document Server

    Al-Ghraibah, Amani; McAteer, R T James

    2015-01-01

    We study the photospheric magnetic field of ~2000 active regions in solar cycle 23 to search for parameters indicative of energy build-up and subsequent release as a solar flare. We extract three sets of parameters: snapshots in space and time- total flux, magnetic gradients, and neutral lines; evolution in time- flux evolution; structures at multiple size scales- wavelet analysis. This combines pattern recognition and classification techniques via a relevance vector machine to determine whether a region will flare. We consider classification performance using all 38 extracted features and several feature subsets. Classification performance is quantified using both the true positive rate and the true negative rate. Additionally, we compute the true skill score which provides an equal weighting to true positive rate and true negative rate and the Heidke skill score to allow comparison to other flare forecasting work. We obtain a true skill score of ~0.5 for any predictive time window in the range 2-24hr, with ...

  12. Build-up and decline of organic matter during PeECE III

    Directory of Open Access Journals (Sweden)

    K. G. Schulz

    2008-05-01

    Full Text Available Increasing atmospheric carbon dioxide (CO2 concentrations due to anthropogenic fossil fuel combustion are currently changing the ocean's chemistry. Increasing oceanic [CO2] and consequently decreasing seawater pH have the potential to significantly impact marine life. Here we describe and analyze the build-up and decline of a natural phytoplankton bloom initiated during the 2005 mesocosm Pelagic Ecosystem CO2 Enrichment study (PeECE III. The draw-down of inorganic nutrients in the upper surface layer of the mesocosms was reflected by a concomitant increase of organic matter until day t11, the peak of the bloom. From then on, biomass standing stocks steadily decreased as more and more particulate organic matter was lost into the deeper layer of the mesocosms. We show that organic carbon export to the deeper layer was significantly enhanced at elevated CO2. This phenomenon might have impacted organic matter remineralization leading to decreased oxygen concentrations in the deeper layer of the high CO2 mesocosms as indicated by deep water ammonium concentrations. This would have important implications for our understanding of pelagic ecosystem functioning and future carbon cycling.

  13. Correction of build-up factor one x-ray hvl measurement

    International Nuclear Information System (INIS)

    Research to obtain the value build-up factor (b) on half value layers (HVL) measurement of diagnostic X-Rays using pocket dosimeter behind aluminium (AI) filter with its thickness vary from 1 to 4 mm. From the measurement it was obtained HVL value of 1.997, 2.596 and 2.718 mmAI for X-Rays of kVp : 80 Kv with 1, 2, 3 and 4 mm filter thickness respectively. HVL value significantly increase with increasing AI filter thickness. Increasing of HVL means increasing filter thickness. From the calculation it was obtained increasing b value relative to 1 mm AI filter of 18.26 and 46% for filter thickness of 2, 3 and 4 mm respectively. Experiment result shows the need of involving b value in HVL calculation of X-Rays if the filter is relatively thick. Calculation of HVL of X-Rays can be carried out with thin layers filter. Key words : x-rays, half value layer, build up factor

  14. Renewable build-up pathways for the US: Generation costs are not system costs

    CERN Document Server

    Becker, Sarah; Andresen, Gorm B; Jacobson, Mark Z; Schramm, Stefan; Greiner, Martin

    2014-01-01

    The transition to a future electricity system based primarily on wind and solar PV is examined for all regions in the contiguous US. We present optimized pathways for the build-up of wind and solar power for least backup energy needs as well as for least cost obtained with a simplified, lightweight model based on long-term high resolution weather-determined generation data. In the absence of storage, the pathway which achieves the best match of generation and load, thus resulting in the least backup energy requirements, generally favors a combination of both technologies, with a wind/solar PV energy mix of about 80/20 in a fully renewable scenario. The least cost development is seen to start with 100% of the technology with the lowest average generation costs first, but with increasing renewable installations, economically unfavorable excess generation pushes it toward the minimal backup pathway. Surplus generation and the entailed costs can be reduced significantly by combining wind and solar power, and/or a...

  15. Prediction of wax buildup in 24 inch cold, deep sea oil loading line

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, R.G.; Sattler, R.E.; Tolonen, W.J.; Pitchford, A.C.

    1981-10-01

    When designing pipelines for cold environments, it is important to know how to predict potential problems due to wax deposition on the pipeline's inner surface. The goal of this work was to determine the rate of wax buildup and the maximum, equlibrium wax thickness for a North Sea field loading line. The experimental techniques and results used to evaluate the waxing potential of the crude oil (B) are described. Also, the theoretic model which was used for predicting the maximum wax deposit thickness in the crude oil (B) loading pipeline at controlled temperatures of 40 F (4.4 C) and 100 F (38 C), is illustrated. Included is a recommendation of a procedure for using hot oil at the end of a tanker loading period in order to dewax the crude oil (B) line. This technique would give maximum heating of the pipeline and should be followed by shutting the hot oil into the pipeline at the end of the loading cycle which will provide a hot oil soaking to help soften existing wax. 14 references.

  16. Integration of micro-filtration into osmotic membrane bioreactors to prevent salinity build-up.

    Science.gov (United States)

    Wang, Xinhua; Yuan, Bo; Chen, Yao; Li, Xiufen; Ren, Yueping

    2014-09-01

    The high salinity remains as one of major obstacles of the osmotic membrane bioreactor (OMBR). In this study, a new pathway was explored to prevent the salinity build-up by integrating the micro-filtration (MF) membrane to the OMBR (MF-OMBR). The results indicated that the salinity characterized by conductivity in the MF-OMBR was effectively alleviated and controlled at a lower value of about 5 mS/cm, and the stable flux of forward osmosis (FO) membrane correspondingly increased to approximately 5.5L/(m(2)h). Besides, the addition of MF membrane in the OMBR could increase the total organic carbon (TOC) and ammonium nitrogen (NH3-N) removals due to the activated sludge by improving the microbial activity. The membrane fouling especially the reversible fouling in the MF-OMBR was severer compared to that in the conventional OMBR, which resulted in a lower water flux than the expectation due to the increase of filtration resistance and external concentration polarization.

  17. The Build-Up Course of Visuo-Motor and Audio-Motor Temporal Recalibration

    Directory of Open Access Journals (Sweden)

    Yoshimori Sugano

    2011-10-01

    Full Text Available The sensorimotor timing is recalibrated after a brief exposure to a delayed feedback of voluntary actions (temporal recalibration effect: TRE (Heron et al., 2009; Stetson et al., 2006; Sugano et al., 2010. We introduce a new paradigm, namely ‘synchronous tapping’ (ST which allows us to investigate how the TRE builds up during adaptation. In each experimental trial, participants were repeatedly exposed to a constant lag (∼150 ms between their voluntary action (pressing a mouse and a feedback stimulus (a visual flash / an auditory click 10 times. Immediately after that, they performed a ST task with the same stimulus as a pace signal (7 flashes / clicks. A subjective ‘no-delay condition’ (∼50 ms served as control. The TRE manifested itself as a change in the tap-stimulus asynchrony that compensated the exposed lag (eg, after lag adaptation, the tap preceded the stimulus more than in control and built up quickly (∼3–6 trials, ∼23–45 sec in both the visuo- and audio-motor domain. The audio-motor TRE was bigger and built-up faster than the visuo-motor one. To conclude, the TRE is comparable between visuo- and audio-motor domain, though they are slightly different in size and build-up rate.

  18. ANALYSIS OF TWO-PHASE FLOW PRESSURE BUILDUP DATA FROM A WELL IN AN INFINITE MULTIWELL RESERVOIR

    Institute of Scientific and Technical Information of China (English)

    LIN Jia-en; YANG Hui-zhu

    2005-01-01

    A general method has been developed for analyzing two-phase flow pressure buildup data from a well located in a system of both production and injection wells completed in an infinite multiwell reservoir. The analysis technique assumes that the tested well has established its own drainage area before shut-in and a linear reservoir pressure trend dominates the well pressure behavior at the instant of shut-in. And for the two-phase flow problems the horizontal saturation gradients are assumed to be negligible. The entire pressure response, whether or not conventional semilog straight lines exist, can be analyzed and the Injection-Production Ratio (IPR), the total fluid (oil/water) mobility, the average drainage-area pressure, and also the skin factor can be calculated much easily. The validity and applicability of the method are demonstrated by a field example. The technique by using the type curves for analyzing the pressure-buildup data is also presented here.

  19. Clinical comparison of various esthetic restorative options for coronal build-up of primary anterior teeth

    Science.gov (United States)

    Duhan, Himanshu; Pandit, Inder Kumar; Srivastava, Nikhil; Gugnani, Neeraj; Gupta, Monika; Kochhar, Gulsheen Kaur

    2015-01-01

    Background: This study was designed to compare the clinical performance of composite, strip crowns, biological restoration, and composite with stainless steel band when used for the coronal build-up of anterior teeth. Materials and Methods: A total of 20 patients aged 3-6 years presenting with mutilated primary anterior teeth due to caries or trauma were selected for the study using randomized simple sampling. A total of 52 primary anterior teeth were randomly divided into four equal groups having 13 teeth in each group. Teeth in Group I were restored with composite, in Group II with strip crowns, in Group III with biologic restoration and with stainless steel band reinforced composite in group IV. The restorations were evaluated for color match, retention, surface texture, and anatomic form according to Ryge's Direct (US Public Health Service) evaluation criteria at baseline (immediate postoperative), after 48 h, 3, 6, and 9 months. The data obtained were statistically analyzed using Chi-square test, and level of significance, that is, P value was determined. Results: At baseline, none of the groups showed any color changes. Other than Group III all other groups showed highly significant changes (P 0.05). Deterioration in surface texture was exhibited maximum by restorations in Group IV followed by Group I at 3 months. Whereas, no surface changes were seen in Group II and III. Only Group I and IV showed discontinuity in anatomic form after 3 months. After 6 months, except in Group II, discontinuity in anatomic form was observed in all the groups. Discontinuity in anatomic form was seen in all the 4 groups after 9 months although the difference was not significant (P > 0.05). Conclusion: Biological restoration was found to be most satisfying esthetically owing to color compatibility with the patient's tooth. Thus, it has a great potential to be used as esthetic restorative option in primary anteriors. PMID:26759595

  20. Clinical comparison of various esthetic restorative options for coronal build-up of primary anterior teeth

    Directory of Open Access Journals (Sweden)

    Himanshu Duhan

    2015-01-01

    Full Text Available Background: This study was designed to compare the clinical performance of composite, strip crowns, biological restoration, and composite with stainless steel band when used for the coronal build-up of anterior teeth. Materials and Methods: A total of 20 patients aged 3-6 years presenting with mutilated primary anterior teeth due to caries or trauma were selected for the study using randomized simple sampling. A total of 52 primary anterior teeth were randomly divided into four equal groups having 13 teeth in each group. Teeth in Group I were restored with composite, in Group II with strip crowns, in Group III with biologic restoration and with stainless steel band reinforced composite in group IV. The restorations were evaluated for color match, retention, surface texture, and anatomic form according to Ryge′s Direct (US Public Health Service evaluation criteria at baseline (immediate postoperative, after 48 h, 3, 6, and 9 months. The data obtained were statistically analyzed using Chi-square test, and level of significance, that is, P value was determined. Results: At baseline, none of the groups showed any color changes. Other than Group III all other groups showed highly significant changes (P 0.05. Deterioration in surface texture was exhibited maximum by restorations in Group IV followed by Group I at 3 months. Whereas, no surface changes were seen in Group II and III. Only Group I and IV showed discontinuity in anatomic form after 3 months. After 6 months, except in Group II, discontinuity in anatomic form was observed in all the groups. Discontinuity in anatomic form was seen in all the 4 groups after 9 months although the difference was not significant (P > 0.05. Conclusion: Biological restoration was found to be most satisfying esthetically owing to color compatibility with the patient′s tooth. Thus, it has a great potential to be used as esthetic restorative option in primary anteriors.

  1. Population analysis of the genera buildup on some commercially important vegetable crops grown in Kashmir Valley.

    Science.gov (United States)

    Sheikh, Javaid Hassan; Chishti, M Z; Rasheed, Majidah; Tak, Irfan-Ur-Rauf; Dar, Shoaib Ali; Lal, Eugenia P; Mohiuddin, Dawood

    2016-09-01

    In order to list the genera buildup on Brassica oleracea (Cauliflower), Capsicum frustscens (Chillies), Spinacia oleracea (Spinach) and Phaseolus vulgaris (Farash bean) a general survey was carried in the summer season of 2013. On examining the soil samples as well as root samples of Cauliflower Boleodorus, Psilenchus, Helicotylenchus, Merlinius, Aglenchus and Filenchus were encountered with their absolute density of 18, 31, 34.5, 35, 35 and 31.5 %. On Chillies, Tylenchus, Helicotylenchus, Psilenchus, Pratylenchus and Hirschmaniella with their absolute frequency of 86, 96.6, 100, 100 and 96.6 % respectively were collected. Among these five genera recorded on Chillies the Relative prominence value of 16 % is lowest for Psilenchus and 26.7 % for Helicotylenchus. Merlinius, Psilenchus, Aglenchus, and Boleodorus were encountered on examining the soil and root samples of Spinach during the period of study. Boleodorus was met with the highest percentage of frequency of 90 % as well as highest proportion of absolute density of 37 % and lowest value of 24 % in case of Merlinius and Psilenchus. Soil samples as well as root samples of Farash bean, Aglenchus, Tylenchus, Hirschmaniella, Helicotylenchus and Psilenchus were encountered with their absolute density of 27, 19.5, 33, 33 and 35.4 %. The absolute frequency of 100 % was found in Tylenchus with the lowest frequency of 70 % in Helicotylenchus. Among the genera recorded on Farash bean relative prominence value happened to be highest in Hirschmaniella with the value as 23.6 % and lowest on Tylenchus with the value of 14.2 %. PMID:27605801

  2. Can captive orangutans (Pongo pygmaeus abelii) be coaxed into cumulative build-up of techniques?

    Science.gov (United States)

    Lehner, Stephan R; Burkart, Judith M; Schaik, Carel P van

    2011-11-01

    While striking cultural variation in behavior from one site to another has been described in chimpanzees and orangutans, cumulative culture might be unique to humans. Captive chimpanzees were recently found to be rather conservative, sticking to the technique they had mastered, even after more effective alternatives were demonstrated. Behavioral flexibility in problem solving, in the sense of acquiring new solutions after having learned another one earlier, is a vital prerequisite for cumulative build-up of techniques. Here, we experimentally investigate whether captive orangutans show such flexibility, and if so, whether they show techniques that cumulatively build up (ratchet) on previous ones after conditions of the task are changed. We provided nine Sumatran orangutans (Pongo pygmaeus abelii) with two types of transparent tubes partly filled with syrup, along with potential tools such as sticks, twigs, wood wool and paper. In the first phase, the orangutans could reach inside the tubes with their hands (Regular Condition), but in the following phase, tubes had been made too narrow for their hands to fit in (Restricted Condition 1), or in addition the setup lacked their favorite materials (Restricted Condition 2). The orangutans showed high behavioral flexibility, applying nine different techniques under the regular condition in total. Individuals abandoned preferred techniques and switched to different techniques under restricted conditions when this was advantageous. We show for two of these techniques how they cumulatively built up on earlier ones. This suggests that the near-absence of cumulative culture in wild orangutans is not due to a lack of flexibility when existing solutions to tasks are made impossible. PMID:21767010

  3. Benchmarking Electron-Cloud Build-Up and Heat-Load Simulations against Large-Hadron-Collider Observations

    OpenAIRE

    Dominguez, O; Iriso, U; Maury, H.; Rumolo, G.; Zimmermann, F

    2011-01-01

    After reviewing the basic features of electron clouds in particle accelerators, the pertinent vacuum-chamber surface properties, and the electron-cloud simulation tools in use at CERN, we report recent observations of electron-cloud phenomena at the Large Hadron Collider (LHC) and ongoing attempts to benchmark the measured LHC vacuum pressure increases and heat loads against electron-cloud build-up simulations aimed at determining the actual surface parameters and at monitoring the so-called ...

  4. Anatomy of a phylloid algal buildup, Raytown Limestone, Iola Formation, Pennsylvanian, Southeast Kansas, U.S.A.

    Science.gov (United States)

    Dawson, William C.; Carozzi, Albert V.

    1986-05-01

    Quantitative petrography and temporal-spatial relationships of microfacies were used to interpret the depositional history of Iola carbonates. The Paola Limestone, consisting of four microfacies, was deposited on a carbonate ramp and appears to record the maximum transgression within the Iola cycle of deposition. The overlying Raytown Limestone was composed of nineteen microfacies arranged in three vertically successive depositional models of similar general configuration. These models revealed an initial bioclastic bar evolving upward into a complex bioaccumulated-bioconstructed phylloid algal buildup. The latter was replaced landward by a siliciclastic distal deltaic environment and graded basinward into upper ramp and lower ramp carbonates. Locally, restricted circulation caused the development of hypersaline conditions. The shallowing-upward depositional evolution of the phylloid algal buildup consisted of four distinct stages: bioclastic (hydrodynamic buildup), bioaccumulation, bioconstruction, and bioclastic (destruction in storm-dominated conditions and intermittent emergence). Diagenesis of Iola microfacies was complex and included: marine phreatic 1 (bioturbation, syneresis, micritization, micrite lithification, and hardground genesis; freshwater vadose—phreatic undersaturated 1 (dissolution of evaporites, moldic dissolution, collapse brecciation, and vadose silt infiltration); marine phreatic 2 (isopachous rim and botryoidal cementation); freshwater phreatic saturated 2 (sparite cementation, and extensive neomorphism); deep burial (anhydritization, dolomitization, stylolitization, and silicification); and late uplift (fracturation and cementation). Most of the diagenesis was microfacies specific.

  5. Evaluation of Geometric Progression (GP) Buildup Factors using MCNP Codes (MCNP6.1 and MCNP5-1.60)

    Science.gov (United States)

    Kim, Kyung-O.; Roh, Gyuhong; Lee, Byungchul

    2016-02-01

    The gamma-ray buildup factors of three-dimensional point kernel code (QAD-CGGP) are re-evaluated by using MCNP codes (MCNP6.1 and MCNPX5-1.60) and ENDF/B-VI.8 photoatomic data, which cover an energy range of 0.015-15 MeV and an iron thickness of 0.5-40 Mean Free Path (MFP). These new data are fitted to the Geometric Progression (GP) fitting function and are then compared with ANS standard data equipped with QAD-CGGP. In addition, a simple benchmark calculation was performed to compare the QAD-CGGP results applied with new and existing buildup factors based on the MCNP codes. In the case of the buildup factors of low-energy gamma-rays, new data are evaluated to be about 5% higher than the existing data. In other cases, these new data present a similar trend based on the specific penetration depth, while existing data continuously increase beyond that depth. In a simple benchmark, the calculations using the existing data were slightly underestimated compared to the reference data at a deep penetration depth. On the other hand, the calculations with new data were stabilized with an increasing penetration depth, despite a slight overestimation at a shallow penetration depth.

  6. The effect of different initial densities of nematode (Meloidogyne javanica) on the build-up of Pasteuria penetrans population

    Institute of Scientific and Technical Information of China (English)

    DARBAN Daim Ali; PATHAN Mumtaz Ali; BHATTI Abdul Ghaffar; MAITELO Sultan Ahmed

    2005-01-01

    Pasteuria penetrans will build-up faster where there is a high initial nematode density and can suppress root-knot nematode populations in the roots of tomato plants. The effect of different initial densities of nematode (Meloidogyne javanica)(150, 750, 1500, 3000) and P. penetrans infected females (F1, F3) densities (F0=control and AC=absolute control without nematode or P. penetrans inoculum) on the build-up of Pasteuria population was investigated over four crop cycles. Two major points of interest were highlighted. First, that within a confined soil volume, densities of P. penetrans can increase >100 times within 2 or 3 crop cycles. Second, from a relatively small amount of spore inoculum, infection of the host is very high. There were more infected females in the higher P. penetrans doses. The root growth data confirms the greater number of females in the controls particularly at the higher inoculum densities in the third and fourth crops. P. penetrans generally caused the fresh root weights to be higher than those in the control. P. penetrans has shown greater reduction of egg masses per plant at most densities.The effects of different initial densities of M. javanica and P. penetrans on the development of the pest and parasite populations were monitored. And no attempt was made to return the P. penetrans spores to the pots after each crop so the build-up in actual numbers of infected females and spores under natural conditions may be underestimated.

  7. Experimental method of in-vivo dosimetry without build-up device on the skin for external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Hosang [Department of Radiation Oncology, Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of); Medical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of); Nam, Jiho; Lee, Jayoung [Department of Radiation Oncology, Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of); Park, Dahl, E-mail: dpark411@gmail.com [Department of Radiation Oncology, Pusan National University Hospital, Busan (Korea, Republic of); Baek, Cheol-Ha [Department of Radiological Science, Dongseo University, Busan (Korea, Republic of); Kim, Wontaek; Ki, Yongkan; Kim, Dongwon [Department of Radiation Oncology, Pusan National University Hospital, Busan (Korea, Republic of)

    2015-06-01

    Accurate dose delivery is crucial to the success of modern radiotherapy. To evaluate the dose actually delivered to patients, in-vivo dosimetry (IVD) is generally performed during radiotherapy to measure the entrance doses. In IVD, a build-up device should be placed on top of an in-vivo dosimeter to satisfy the electron equilibrium condition. However, a build-up device made of tissue-equivalent material or metal may perturb dose delivery to a patient, and requires an additional laborious and time-consuming process. We developed a novel IVD method using a look-up table of conversion ratios instead of a build-up device. We validated this method through a monte-carlo simulation and 31 clinical trials. The mean error of clinical IVD is 3.17% (standard deviation: 2.58%), which is comparable to that of conventional IVD methods. Moreover, the required time was greatly reduced so that the efficiency of IVD could be improved for both patients and therapists.

  8. Calculation of Buildup Factor for Gamma-ray Exposure in Two Layered Shields Made of Water and Lead

    International Nuclear Information System (INIS)

    The buildup factor for gamma ray exposure is most useful in calculations for biological protective shields.The buildup factors for gamma ray exposure were calculated in tow layered shields consist of water-lead and lead-water up to optical Thickness 20 mean free path (mfp) at gamma ray energies 1, 2 and 6MeV by using kalos's formula.The program has been designed to work at any atomic number of the attenuating medium, photon energy, slab thickness and and the arrangement of materials.The results obtained in this search leading to the buildup factor for gamma ray exposure at energies (1and2MeV) in lead-water were higher than the reverse case,while at energy 6 MeV the effect was opposite.The calculated data were parameterized by an empirical formula as a function of optical thickness of tow materials.The results obtained were in reasonable agreement with a previous work

  9. Evaluation of Geometric Progression (GP Buildup Factors using MCNP Codes (MCNP6.1 and MCNP5-1.60

    Directory of Open Access Journals (Sweden)

    Kim Kyung-O

    2016-01-01

    Full Text Available The gamma-ray buildup factors of three-dimensional point kernel code (QAD-CGGP are re-evaluated by using MCNP codes (MCNP6.1 and MCNPX5-1.60 and ENDF/B-VI.8 photoatomic data, which cover an energy range of 0.015–15 MeV and an iron thickness of 0.5–40 Mean Free Path (MFP. These new data are fitted to the Geometric Progression (GP fitting function and are then compared with ANS standard data equipped with QAD-CGGP. In addition, a simple benchmark calculation was performed to compare the QAD-CGGP results applied with new and existing buildup factors based on the MCNP codes. In the case of the buildup factors of low-energy gamma-rays, new data are evaluated to be about 5% higher than the existing data. In other cases, these new data present a similar trend based on the specific penetration depth, while existing data continuously increase beyond that depth. In a simple benchmark, the calculations using the existing data were slightly underestimated compared to the reference data at a deep penetration depth. On the other hand, the calculations with new data were stabilized with an increasing penetration depth, despite a slight overestimation at a shallow penetration depth.

  10. Understanding the uncertainty associated with particle-bound pollutant build-up and wash-off: A critical review.

    Science.gov (United States)

    Wijesiri, Buddhi; Egodawatta, Prasanna; McGree, James; Goonetilleke, Ashantha

    2016-09-15

    Accurate prediction of stormwater quality is essential for developing effective pollution mitigation strategies. The use of models incorporating simplified mathematical replications of pollutant processes is the common practice for determining stormwater quality. However, an inherent process uncertainty arises due to the intrinsic variability associated with pollutant processes, which has neither been comprehensively understood, nor well accounted for in uncertainty assessment of stormwater quality modelling. This review provides the context for defining and quantifying the uncertainty associated with pollutant build-up and wash-off on urban impervious surfaces based on the hypothesis that particle size is predominant in influencing process variability. Critical analysis of published research literature brings scientific evidence together in order to establish the fact that particle size changes with time, and different sized particles exhibit distinct behaviour during build-up and wash-off, resulting in process variability. Analysis of the different adsorption behaviour of particles confirmed that the variations in pollutant load and composition are influenced by particle size. Particle behaviour and variations in pollutant load and composition are related due to the strong affinity of pollutants such as heavy metals and hydrocarbons for specific particle size ranges. As such, the temporal variation in particle size is identified as the key to establishing a basis for assessing build-up and wash-off process uncertainty. Therefore, accounting for pollutant build-up and wash-off process variability, which is influenced by particle size, would facilitate the assessment of the uncertainty associated with modelling outcomes. Furthermore, the review identified fundamental knowledge gaps where further research is needed in relation to: (1) the aggregation of particles suspended in the atmosphere during build-up; (2) particle re-suspension during wash-off; (3) pollutant

  11. A comprehensive interpretation of the NEEM basal ice build-up using a multi parametric approach

    Directory of Open Access Journals (Sweden)

    T. Goossens

    2015-10-01

    propose a first interpretative framework for the build-up of the NEEM basal ice sequence, based on the origin of the various ice types.

  12. Deposit buildup on prosthetic eyes and implications for conjunctival inflammation and mucoid discharge

    Directory of Open Access Journals (Sweden)

    Pine KR

    2012-10-01

    Full Text Available Keith Raymond Pine,1 Brian Sloan,2 Robert John Jacobs11Department of Optometry and Vision Science, 2New Zealand National Eye Centre, The University of Auckland, Auckland, New ZealandBackground: The aim of this study was to investigate deposit buildup on prosthetic eyes and the implications for conjunctival inflammation and discharge.Methods: Forty-three prosthetic eye wearers participated in the study. Twenty-three had their prostheses polished normally before being worn continuously for 2 weeks. After this time, surface deposits were stained, photographed, and graded. The prostheses were then repolished to optical quality contact lens standard and worn for a further 2 weeks, when the deposits were again stained, photographed, and graded. Two participants had deposits on their prostheses stained, photographed, and graded on nine occasions at decreasing intervals ranging from 1 year to 1 day. Eighteen participants had the wetting angles on their prostheses measured with a goniometer before and after cleaning, after polishing normally, after polishing to optical quality contact lens standard, and after 10 minutes of wearing their optical quality contact lens polished prostheses. Concordance correlation, multiple regression, and paired t-tests were used for the statistical analysis.Results: More surface deposits accumulated on prostheses polished normally than on those polished to an optical quality contact lens standard after 2 weeks of wear. The interpalpebral zone of most prostheses (observed without magnification appeared to be clear of deposits. Removal of deposits significantly decreased surface wettability, but wettability returned after 10 minutes of wear. Optical quality contact lens polishing produced more wettable surfaces and a slower rate of deposit accumulation than normal polishing.Conclusion: We recommend that an optical quality contact lens standard be the minimum standard of finish for prosthetic eyes. This standard may assist the

  13. Deposit buildup on prosthetic eye material (in vitro and its effect on surface wettability

    Directory of Open Access Journals (Sweden)

    Pine KR

    2013-02-01

    Full Text Available Keith Raymond Pine,1 Brian Sloan,2 KyuYeon Ivy Han,1 Simon Swift,3 Robert John Jacobs11Department of Optometry and Vision Science, New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand; 2New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand; 3Department of Molecular Medicine and Pathology, School of Medical Sciences, The University of Auckland, Auckland, New ZealandBackground: The aim of this in-vitro study was to investigate the effect of different polishing standards on prosthetic eye material (poly(methyl methacrylate [PMMA] on surface wettability and the rate of protein and lipid buildup.Methods: Sample disks (12 mm diameter × 1 mm thickness of PMMA were polished to three different standards of surface finish: low, normal, and optical quality contact lens standard. The sample disks were incubated in a protein-rich artificial tear solution (ATS for the following periods of time: 1 second, 30 minutes, 1 hour, 4 hours, 24 hours, and 14 days. Surface wettability was measured with a goniometer before and after protein deposits were removed. One-way analysis of variance and paired-samples t-test were used for the statistical analysis.Results: Between 13.64 and 62.88 µg of protein adhered to the sample disks immediately upon immersion in ATS. Sample disks with the highest polish attracted less protein deposits. The sample disks polished to optical quality contact lens standard were more wettable than those less highly polished, and wettability significantly decreased following removal of protein deposits. The addition of lipids to protein-only ATS made no difference to the amount of protein deposited on the sample disks for any of the standards of surface polish tested.Conclusion: The findings are consistent with the results of the in-vivo investigation reported previously by the authors. Our view that the minimum standard of polish for prosthetic eyes should be optical quality contact

  14. A comprehensive interpretation of the NEEM basal ice build-up using a multi parametric approach

    Science.gov (United States)

    Goossens, T.; Sapart, C. J.; Dahl-Jensen, D.; Popp, T.; El Amri, S.; Tison, J. L.

    2015-10-01

    interpretative framework for the build-up of the NEEM basal ice sequence, based on the origin of the various ice types.

  15. Exposure buildup factors for bakelite, perspex and magnox-A12 up to 40 m.f.p. using the interpolation method

    Science.gov (United States)

    Brar, G. S.; Sandhu, Apjit Kaur; Singh, Makhan; Mudahar, Gurmel S.

    1994-11-01

    The Geometric Progression (G-P) fitting parameters have been computed with respect to the equivalent atomic number for the composite materials of bakelite and perspex by the interpolation method. These parameters are then used to generate the exposure buildup factors up to 40 m.f.p. in the energy range of 0.015-15.0 MeV for these materials. The behaviour of buildup factors is shown in the form of plots as a function of penetration depth.

  16. Understanding the build-up of supermassive black holes and galaxies

    Science.gov (United States)

    Carrera, Francisco; Ueda, Yoshihiro; Georgakakis, Antonis

    2016-07-01

    . The excellent survey capabilities of Athena/WFI (effective area, angular resolution, field of view) will allow to measure the incidence of feedback in the shape of warm absorbers and Ultra Fast Outflows among the general population of AGN, as well as to complete the census of black hole growth by detecting and characterising significant samples of the most heavily obscured (including Compton thick) AGN, to redshifts z~3-4. The outstanding spectral throughput and resolution of Athena/X-IFU will permit measuring the energetics of those outflows to assess their influence on their host galaxies. The demographics of the heavily obscured and outflowing populations relative to their hosts are fundamental for understanding how major black hole growth events relate to the build-up of galaxies.

  17. On scale and magnitude of pressure build-up induced by large-scale geologic storage of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Q.; Birkholzer, J. T.

    2011-05-01

    The scale and magnitude of pressure perturbation and brine migration induced by geologic carbon sequestration is discussed assuming a full-scale deployment scenario in which enough CO{sub 2} is captured and stored to make relevant contributions to global climate change mitigation. In this scenario, the volumetric rates and cumulative volumes of CO{sub 2} injection would be comparable to or higher than those related to existing deep-subsurface injection and extraction activities, such as oil production. Large-scale pressure build-up in response to the injection may limit the dynamic storage capacity of suitable formations, because over-pressurization may fracture the caprock, may drive CO{sub 2}/brine leakage through localized pathways, and may cause induced seismicity. On the other hand, laterally extensive sedimentary basins may be less affected by such limitations because (i) local pressure effects are moderated by pressure propagation and brine displacement into regions far away from the CO{sub 2} storage domain; and (ii) diffuse and/or localized brine migration into overlying and underlying formations allows for pressure bleed-off in the vertical direction. A quick analytical estimate of the extent of pressure build-up induced by industrial-scale CO{sub 2} storage projects is presented. Also discussed are pressure perturbation and attenuation effects simulated for two representative sedimentary basins in the USA: the laterally extensive Illinois Basin and the partially compartmentalized southern San Joaquin Basin in California. These studies show that the limiting effect of pressure build-up on dynamic storage capacity is not as significant as suggested by Ehlig-Economides and Economides, who considered closed systems without any attenuation effects.

  18. Simulation of Electron-Cloud Build-Up for the Cold Arcs of the LHC and Comparison with Measured Data

    CERN Document Server

    Maury Cuna, H; Rumolo, G; Tavian, L; Zimmermann, F

    2011-01-01

    The electron cloud generated by synchrotron radiation or residual gas ionization is a concern for LHC operation and performance. We report the results of simulations studies which examine the electron cloud build-up, at injection energy, 3.5 TeV for various operation parameters. In particular, we determine the value of the secondary emission yield corresponding to the multipacting threshold, and investigate the electron density, and heat as a function of bunch intensity for dipoles and field-free regions. We also include a comparison between simulations results and measured heat-load data from the LHC scrubbing runs in 2011.

  19. Surface analytical characterization of chromium-stabilized protecting oxide layers on stainless steel referring to activity buildup

    Science.gov (United States)

    Thieme, M.; Scharnweber, D.; Drechsler, L.; Heiser, C.; Adolphi, B.; Weiss, A.

    1992-08-01

    Surface analytical methods were used to characterize both protecting oxide layers formed by hydrothermal chromate treatment (HTCT) on stabilized austenitic stainless steel and hydrothermally grown corrosion product layers (CPL) within the scope of lowering the activity buildup in the primary circuit of nuclear power plants. Morphology, thickness and chromium depth distribution of the layers proved to be considerably different from each other. According to Raman microspectrometry, there were also alterations in the chemical nature of the oxide species. Preceding electropolishing gave rise to particular properties of the respective layers. Prerequisites for an optimal corrosion behaviour of the protecting layers are discussed. Titanium-containing precipitations were oxidatively transformed by HTCT.

  20. Comprehensive study on energy absorption buildup factors and exposure buildup factors for photon energy 0.015 to 15 MeV up to 40 mfp penetration depth for gel dosimeters

    International Nuclear Information System (INIS)

    The gel dosimeter comprises of phantom, dosimetric material and three-D spatial dose distribution has advantages over one- and two-D dosimeters. Energy absorption buildup factor (EABF) and exposure buildup factor (EBF) values of sixteen gel dosimeters have been computed for photon energy 0.015 to 15 MeV up to 40 mfp (mean free path) penetration depths. Kerma of the gel dosimeters were computed for photon energy 1 keV to 20 MeV. The water and PMMA phantom equivalence of the gel dosimeters was evaluated using EABF, and large difference was noted below 1 MeV photon energy. This study should be useful for estimation of effective dose to the human organs and simulation of the dose for radiation therapy and various medical applications. - Highlights: • EABF and EBF values of 16 gel dosimeters were computed using GP fitting method. • Water and PMMA equivalence was investigated using EABF. • Ratio of EABF of BANG1 to water and PMMA is close to unity above 1 MeV. • Photon kerma relative to air of PRESAGE shows a peak at 40 keV

  1. Study of radiation build-up and spectral evolution in the Israeli electrostatic accelerator free-electron laser oscillator

    CERN Document Server

    Abramovich, A; Yakover, Y; Gover, A; Sokolowski, J S; Canter, M

    1999-01-01

    Time-frequency study of oscillation build-up in an electrostatic accelerator free-electron laser (EA-FEL) oscillator is presented. The unique features of EA-FEL and its capacity to operate in a long pulse mode, enable observation and study of linear and non-linear processes taking place in the evolution of radiation in the EA-FEL oscillator. The experimental data recorded with the aid of a digital 4 GS/s fast sampling oscilloscope, was analyzed using various signal processing techniques to obtain time-frequency phase space presentation of the power spectral density evolution. This presentation make it possible to follow the radiation field coherence evolution from noise to saturation including intermediate stages of mode build-up from noise and competition between longitudinal modes until single-mode steady-state operation is established. The experimental results were also compared with the results of a FEL oscillator simulation code. The code predicts well the behavior of the oscillator in its various regime...

  2. Design and metrological evaluation of the new 5 MN hexapod-shaped multicomponent build-up system

    Science.gov (United States)

    Palumbo, Stefano; Germak, Alessandro; Mazzoleni, Fabrizio; Desogus, Sergio; Barbato, Giulio

    2016-06-01

    The new 5 MN hexapod-shaped multicomponent build-up system (HSM-BUS) represents significant progress in the field of reference transducers in the high force range. As with any build-up system, the presented hexapod-shaped multicomponent force transducer can lead, not only to measure forces 5 times higher than the capacity of a each single uniaxial force transducer (UFT), but gives also information about the other components of the force vector and of the moment vector. Furthermore, the calibration of such types of multicomponent force transducer regards only the calibration of the signal outputs coming from each UFT and the calibration of the geometry of the system. In this work, an a priori evaluation of the expected uncertainty is performed. As a first approximation, the effects of the calibration uncertainties of UFTs and of the geometrical tolerances given on the construction drawing were considered. Subsequently, with a finite element simulation of the mechanical behavior of the 5 MN HSM-BUS under load, a mathematical model of elastic deformations has been evaluated and applied for evaluating and correcting the systematic errors due to the deformation of the geometry under load.

  3. Gamma-ray double-layered transmission exposure buildup factors of some engineering materials, a comparative study

    Science.gov (United States)

    Mann, Kulwinder Singh; Heer, Manmohan Singh; Rani, Asha

    2016-08-01

    Comparative study on various deterministic methods and formulae of double layered transmission exposure buildup factors (DLEBF) for point isotropic gamma-ray sources has been performed and the results are provided here. This investigation has been performed on some commonly available engineering materials for the purpose of gamma-ray shielding. In reality, the presence of air around the gamma-ray shield motivated to focus this study on exposure buildup factor (EBF). DLEBF have been computed at four energies viz. 0.5, 1.0, 2.0 and 3.0 MeV for various combinations of the chosen five samples taken two at a time with combined optical thickness up to 8 mean free path (mfp). For the necessary computations for DLEBF, a computer program (BUF-toolkit) has been designed. Comparison of Monte Carlo (EGS4-code) and Geometric Progression (G.P.) fitting point kernel methods were done for DLEBF computation. It is concluded that empirical formula given by Lin and Jiang using EBF computed by G.P. fitting formula is the most accurate and easiest method for DLEBF computations. It was observed that DLEBF values at selected energies for two layered slabs with an orientation (low-Z material followed by high-Z material) were lower than the opposite orientation. For optical thickness up to 8 mfp and chosen energy range (0.5-3.0 MeV), Aluminum-Lime Stone shield, appears to provide the best protection against the gamma-rays.

  4. Energy absorption and exposure buildup factors for some polymers and tissue substitute materials: photon energy, penetration depth and chemical composition dependence

    Energy Technology Data Exchange (ETDEWEB)

    Kurudirek, Murat; Oezdemir, Yueksel, E-mail: mkurudirek@gmail.com [Faculty of Science, Department of Physics, Ataturk University, 25240, Erzurum (Turkey)

    2011-03-01

    The gamma ray energy absorption and exposure buildup factors have been calculated by using the five parameter geometric progression (GP) fitting formula for some polymers and tissue substitute materials in the energy region 0.015-15 MeV up to a penetration depth of 40 mean free paths. From the results, it is worth noting that significant variations occur in gamma ray buildup factors for the given polymers and tissue substitute materials depending on photon energy, penetration depth and chemical composition of the materials. Also, it was observed that there are significant variations between energy absorption (EABF) and exposure (EBF) buildup factors which may be due to the variations in chemical composition of the materials used. Finally, it is expected that the presented buildup factor data may be helpful in (a) estimating the effective dose to be given to patients in radiation therapy and diagnostics, hence allowing corrections to be made to the intensity of radiation, as it is somewhat problematic to evaluate the real absorbed dose in critical organs due to the probability of photon buildup somewhere inside the medium; (b) estimating the health hazards arising from the exposure of the human body to radiation, thus it will be helpful in controlling the exposure of the human body to radiation.

  5. Ball phantom for dosimetry of surface and build-up region in megavoltage photon beam of oblique incidence through the couch

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yu-Chuan [Department of Radiation Oncology, Tainan Sin-Lau Hospital, The Presbyterian Church in, Taiwan (China); Institute of Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Chen, Hsin-Hsiung [Institute of Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Ho, Sheng-Yow [Department of Radiation Oncology, Tainan Sin-Lau Hospital, The Presbyterian Church in, Taiwan (China); Kuo, Chung-Ming [Department of Information Engineering, I-Shou University, Taiwan (China); Chen, Ching-Jiang [Department of Medical Imaging and Radiological Sciences, I-Shou University, Kaohsiung, Taiwan (China); Min Chao, Max [Institute of Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Niu, H.; Chao, J.H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Wu, Jia-Ming, E-mail: rtojmwu@gmail.com [Institute of Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Department of Radiation Oncology, E-Da Hospital, Kaohsiung, Taiwan (China); Chen, Tzong-Jer [Department of Medical Imaging and Radiology, Shu-Zen College of Medicine and Management, Taiwan (China); Wu, Jin-Tze [Department of Radiation Oncology, E-Da Hospital, Kaohsiung, Taiwan (China)

    2011-10-01

    This study investigates surface dose and build-up region dosimetry as well as beam attenuation by ball phantom for coplanar and non-coplanar oblique photon beam incidence through a treatment couch in radiation therapy. The dosimetry of the surface and build-up region and attenuating incidence of true posterior and maximum oblique incidence (15{sup 0} below surface) beams on the treatment couch are measured and compared with an open field. Photon calculation kernels of the computerized treatment planning system do not include the factor of scatter doses induced by the couch in the build-up region. These scatter doses can have some implications for skin reactions. Therefore, monitor unit calculation is necessary in posterior oblique angles or non-coplanar incidence of the treatment couch.

  6. The solar physics Shuttle/Spacelab program and its relationship to studies of the flare build-up

    Science.gov (United States)

    Neupert, W. M.

    1976-01-01

    The main phase of solar physics (including flare-buildup) research on Shuttle/Spacelab during the 1980s centers around the use of facility instruments for multiple-user, multiple flight operations. Three main facilities are being considered: a meter-class optical telescope for visible and near-UV wavelengths, an EUV/XUV/soft X-ray facility, and a hard X-ray imaging facility (including a full-sun 5-600 keV spectrometer, a nuclear gamma ray spectrometer, and an X-ray polarimeter for the 5-100 keV range). Smaller instruments designed for specific observations and other classes of instruments such as solar monitors that are not on the facility level are also being considered.

  7. Benchmarking Electron-Cloud Build-Up and Heat-Load Simulations against Large-Hadron-Collider Observations

    CERN Document Server

    Dominguez, O; Maury, H; Rumolo, G; Zimmermann, F

    2011-01-01

    After reviewing the basic features of electron clouds in particle accelerators, the pertinent vacuum-chamber surface properties, and the electron-cloud simulation tools in use at CERN, we report recent observations of electron-cloud phenomena at the Large Hadron Collider (LHC) and ongoing attempts to benchmark the measured LHC vacuum pressure increases and heat loads against electron-cloud build-up simulations aimed at determining the actual surface parameters and at monitoring the so-called scrubbing process. Finally, some other electron-cloud studies related to the LHC are mentioned, and future study plans are described. Presented at MulCoPim2011, Valencia, Spain, 21-23 September 2011.

  8. Endodontic treatment and esthetic management of a primary double tooth with direct composite using silicone buildup guide

    Directory of Open Access Journals (Sweden)

    Vinaya Kumar Kulkarni

    2012-01-01

    Full Text Available Gemination and fusion are morphological dental anomalies, characterized by the formation of a clinically wide tooth. Gemination occurs when one tooth bud tries to divide, while fusion occurs if two buds unite. The terms double teeth, double formation, conjoined teeth, geminifusion, vicinifusion and dental twinning are often used to describe fusion and gemination. Double teeth are associated with clinical problems such as poor esthetics, spacing problems and caries susceptibility. Management of such cases requires a comprehensive knowledge of the clinical entity as well as the problems associated with it. This report presents a case of primary double tooth in a 6-year-old boy involving maxillary left central incisor. The anomalous tooth was carious and pulpally involved. This was treated conservatively by endodontic treatment and esthetic rehabilitation was done with direct composite restoration using a silicone buildup guide. The treated tooth was followed up until exfoliation.

  9. Resonant laser power build-up in ALPS. A 'light-shining-through-walls' experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ehret, Klaus; Ghazaryan, Samvel [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Frede, Maik [Laser Zentrum Hannover e.V. (DE)] (and others)

    2009-05-15

    The ALPS collaboration runs a light-shining-through-walls (LSW) experiment to search for photon oscillations into weakly interacting sub-eV particles (WISPs) inside of a superconducting HERA dipole magnet at the site of DESY. In this paper we report on the first successful integration of a large-scale optical cavity to boost the available power for WISP production in this type of experiments. The key elements are a frequency tunable narrow line-width continuous wave laser acting as the primary light source and an electronic feed-back control loop to stabilize the power build-up. We describe and characterize our apparatus and demonstrate the data analysis procedures on the basis of a brief exemplary run. (orig.)

  10. Characterization of deposits build-up on austenitic stainless steel AISI 316L exposed in high purity water system

    International Nuclear Information System (INIS)

    For the characterization of deposit layers on AISI 316L surfaces in high purity water systems, operating up to 80 deg C Moessbauer spectroscopy (ME), scanning electron microscopy (SEM), X-ray fluorescence (XRF) and X-ray photoelectron spectroscopy (XPS) are used. Austenitic steel particles were identified on the surfaces of systems not properly cleaned before start-up. Long exposition of austenitic surfaces to high purity water promotes the build-up, composed by trivalent iron and chromium oxidehydroxides and oxide. The oxidehydroxide phase is located mainly at the solid-water interface, whereas oxide phase is in direct contact with metal. Spheroid-like morphology of particles in these layers and the lack of metal attack suggest that coagulation and crystallization processes are the way for oxide production from existing dissolved species. (author)

  11. Temperature effect on the build-up of exponentially growing polyelectrolyte multilayers. An exponential-to-linear transition point.

    Science.gov (United States)

    Vikulina, Anna S; Anissimov, Yuri G; Singh, Prateek; Prokopović, Vladimir Z; Uhlig, Katja; Jaeger, Magnus S; von Klitzing, Regine; Duschl, Claus; Volodkin, Dmitry

    2016-03-21

    In this study, the effect of temperature on the build-up of exponentially growing polyelectrolyte multilayer films was investigated. It aims at understanding the multilayer growth mechanism as crucially important for the fabrication of tailor-made multilayer films. Model poly(L-lysine)/hyaluronic acid (PLL/HA) multilayers were assembled in the temperature range of 25-85 °C by layer-by-layer deposition using a dipping method. The film growth switches from the exponential to the linear regime at the transition point as a result of limited polymer diffusion into the film. With the increase of the build-up temperature the film growth rate is enhanced in both regimes; the position of the transition point shifts to a higher number of deposition steps confirming the diffusion-mediated growth mechanism. Not only the faster polymer diffusion into the film but also more porous/permeable film structure are responsible for faster film growth at higher preparation temperature. The latter mechanism is assumed from analysis of the film growth rate upon switching of the preparation temperature during the film growth. Interestingly, the as-prepared films are equilibrated and remain intact (no swelling or shrinking) during temperature variation in the range of 25-45 °C. The average activation energy for complexation between PLL and HA in the multilayers calculated from the Arrhenius plot has been found to be about 0.3 kJ mol(-1) for monomers of PLL. Finally, the following processes known to be dependent on temperature are discussed with respect to the multilayer growth: (i) polymer diffusion, (ii) polymer conformational changes, and (iii) inter-polymer interactions. PMID:26911320

  12. Note: Utilization of polymer gel as a bolus compensator and a dosimeter in the near-surface buildup region for breast-conserving therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fuse, Hiraku, E-mail: fuseh@ipu.ac.jp; Inohira, Masaya; Kawamura, Hiraku; Fujisaki, Tatsuya [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Inashiki-gun, Ibaraki 300-0331 (Japan); Shinoda, Kazuya [Graduate School of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki (Japan); Department of Radiological Technology, Tsukuba Medical Center Hospital, Tsukuba (Japan); Miyamoto, Katsumi [Department of Radiological Technology, Tsukuba Medical Center Hospital, Tsukuba (Japan); Sakae, Takeji [Faculty of Medicine, University of Tsukuba, Tsukuba (Japan)

    2015-09-15

    Tangential beam radiotherapy is routinely used for radiation therapy after breast conserving surgery. A tissue-equivalent bolus placed on the irradiated area shifts the depth of the dose distribution; this bolus provides uniform dose distribution to the breast. The gel bolus made by the BANG-Pro{sup ®} polymer gel and in an oxygen non-transmission pack was applicable as a dosimeter to measure dose distribution in near-surface buildup region. We validated the use of the gel bolus to improve in the whole-breast/chest wall, including the near-surface buildup region.

  13. Enhanced damage buildup in C{sup +}-implanted GaN film studied by a monoenergetic positron beam

    Energy Technology Data Exchange (ETDEWEB)

    Li, X. F.; Chen, Z. Q., E-mail: chenzq@whu.edu.cn; Liu, C. [Department of Physics, Hubei Nuclear Solid Physics Key Laboratory, Wuhan University, Wuhan 430072 (China); Zhang, H. J.; Kawasuso, A. [Advanced Science Research Center, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2015-02-28

    Wurtzite GaN films grown by hydride vapor phase epitaxy were implanted with 280 keV C{sup +} ions to a dose of 6 × 10{sup 16 }cm{sup −2}. Vacancy-type defects in C{sup +}-implanted GaN were probed using a slow positron beam. The increase of Doppler broadening S parameter to a high value of 1.08–1.09 after implantation indicates introduction of very large vacancy clusters. Post-implantation annealing at temperatures up to 800 °C makes these vacancy clusters to agglomerate into microvoids. The vacancy clusters or microvoids show high thermal stability, and they are only partially removed after annealing up to 1000 °C. The other measurements such as X-ray diffraction, Raman scattering and Photoluminescence all indicate severe damage and even disordered structure induced by C{sup +}-implantation. The disordered lattice shows a partial recovery after annealing above 800 °C. Amorphous regions are observed by high resolution transmission electron microscopy measurement, which directly confirms that amorphization is induced by C{sup +}-implantation. The disordered GaN lattice is possibly due to special feature of carbon impurities, which enhance the damage buildup during implantation.

  14. Evaluation of buildup of activated corrosion products for highly compact marine reactor DRX without primary coolant water purification system

    Energy Technology Data Exchange (ETDEWEB)

    Odano, Naoteru; Ishida, Toshihisa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-03-01

    Japan Atomic Energy Research Institute has studied a highly compact reactor DRX for deep-sea research. The DRX has no purification system to achieve compact and light weight design by simplification of the system. The DRX is designed to operate for one month without purification of the primary coolant water. To quantitatively evaluate the validity of reactor operation without a purification system, a computer code CTAM-II has been developed to calculate accumulation of the activated corrosion products during and after reactor operation. The code is an improved and modified version of CTAM, which was developed for the shield modification project of the nuclear ship Mutsu. Validity of CTAM-II and parameters used in the code has been confirmed by comparison of the calculated data and experimental ones for measurement of the concentrations of radioactive materials in the primary coolant water. Estimation of buildup of the corrosion products for DRX using CTAM-II has been carried out and shielding calculations using source terms calculated from CTAM-II have been performed. A radiation safety assessment of the DRX without the purification system has been carried out by these shielding calculations. (author)

  15. On stress-forecasting strategy of earthquakes from stress buildup, stress shadow and stress transfer (SSS) based on numerical approach

    Institute of Scientific and Technical Information of China (English)

    Chunan Tang; Tianhui Ma; Xiaoli Ding

    2009-01-01

    Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR), used for monitoring crust deformation, are found to be very promising in earthquake prediction subject to stress-forecasting. However, it is rec-ognized that unless we can give reasonable explanations of these curious precursory phenomena that continue to be seren-dipitously observed fi'om time to time, such high technology of GPS or InSAR is difficult to be efficiently used. Therefore, a proper model revealing the relation between earthquake evolution and stress variation, such as the phenomena of stress buildup, stress shadow and stress transfer (SSS), is crucial to the GPS or lnSAR based earthquake prediction. Here we ad-dress this question through a numerical approach of earthquake development using an intuitive physical model with a map-like configuration of discontinuous fault system. The simulation provides a physical basis for the principle of stress-forecasting of earthquakes based on SSS and for the application of GPS or InSAR in earthquake prediction. The ob-served SSS associated phenomena with images of stress distribution during the failure process can be continuously simulated. It is shown that the SSS are better indicators of earthquake precursors than that of seismic foreshocks, suggesting a predict-ability of earthquakes based on stress-forecasting strategy.

  16. Effect of the thermoplastic masks on dose distribution in the build-up region for photon beams

    Science.gov (United States)

    Półtorak, Michał; Fujak, Edyta; Kukołowicz, Paweł

    2016-03-01

    The aim of the study was to investigate the influence of thermoplastic masks material (Klarity Medical&Equipment Co., Guangzhou, China) with different diameters of holes (ϕ 0.25 cm and ϕ 0.40 cm) on the dose distribution in the build-up region for photon beams. Measurements were made for external radiation beams produced by the linear accelerator (TrueBeam, Varian Medical Systems, Inc., Palo Alto, CA, USA) using the Markus parallel plane ionization chamber and the Unidos electrometer (both from PTW, Freiburg, Germany). Measurements were made in a solid water phantom for two photon energies 6 MV and 15 MV, at 90 cm source to skin distance, for four fields of 5 cm × 5 cm, 10 cm × 10 cm, 15 cm × 15 cm and 20 cm × 20 cm. Compared to the open field, the maximum dose with mask was closer to the surface of the phantom by about 1.4 mm and 1.2 mm for 6 MV and 15 MV X-Rays, respectively. The surface dose increase from 10% to 42% for 6 MV and from 5% to 28% for 15 MV X-Rays.

  17. Decomposition of litter and soil organic matter - Can we distinguish a mechanism for soil organic matter buildup ?

    International Nuclear Information System (INIS)

    This synthesis paper presents a model for estimating the buildup of soil organic matter in various types of coniferous forests. The knowledge used was obtained from a well-studied forest with good litterfall data, decomposition information and validation measurements of the soil organic matter layer. By constructing a simple model for litterfall, and the information on maximum decomposition levels for litter, we could estimate the annual increase in soil organic matter and extend this to encompass stand age. The validation measurement and the estimated amount of soil organic matter differed by about 8 or 26% over a 120-yr period, depending on the litterfall model. The estimated increased storage of soil organic matter as a consequence of climate change was found to be drastic. We thus found that the soil organic matter layer would grow about four times as fast as a result of the needle component only. This estimate was based on a comparison between latitudes with a difference of 17 degrees. 35 refs, 7 figs, 3 tabs

  18. Determination of neutron buildup factor using analytical solution of one-dimensional neutron diffusion equation in cylindrical geometry

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Julio Cesar L.; Vilhena, Marco Tullio, E-mail: julio.lombaldo@ufrgs.b, E-mail: vilhena@pq.cnpq.b [Universidade Federal do Rio Grande do Sul (DMPA/UFRGS), Porto Alegre, RS (Brazil). Dept. de Matematica Pura e Aplicada. Programa de Pos Graduacao em Matematica Aplicada; Borges, Volnei; Bodmann, Bardo Ernest, E-mail: bardo.bodmann@ufrgs.b, E-mail: borges@ufrgs.b [Universidade Federal do Rio Grande do Sul (PROMEC/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

    2011-07-01

    The principal idea of this work, consist on formulate an analytical method to solved problems for diffusion of neutrons with isotropic scattering in one-dimensional cylindrical geometry. In this area were develop many works that study the same problem in different system of coordinates as well as cartesian system, nevertheless using numerical methods to solve the shielding problem. In view of good results in this works, we starting with the idea that we can represent a source in the origin of the cylindrical system by a Delta Dirac distribution, we describe the physical modeling and solved the neutron diffusion equation inside of cylinder of radius R. For the case of transport equation, the formulation of discrete ordinates S{sub N} consists in discretize the angular variables in N directions and in using a quadrature angular set for approximate the sources of scattering, where the Diffusion equation consist on S{sub 2} approximated transport equation in discrete ordinates. We solved the neutron diffusion equation with an analytical form by the finite Hankel transform. Was presented also the build-up factor for the case that we have neutron flux inside the cylinder. (author)

  19. Hydrocarbon-derived carbonate buildups of the northern Gulf of Mexico continental slope: A review of submersible investigations

    Science.gov (United States)

    Roberts, Harry H.; Aharon, Paul

    1994-06-01

    Hydrocarbon-derived and microbially mediated authigenic carbonates occur over the entire depth range of the northern Gulf of Mexico slope. These carbonates consist of nodules and incipient nodules in surface sediments, hardgrounds and isolated slabs, and moundlike buildups of up to 10 20 m relief above the surrounding seafloor. The authigenic carbonates are characterized byδ 13C negative values in the range -18‰ to -55‰ (PDB) suggesting mixing of seawater carbon with13C-depleted carbon sources ranging from crude oil to biogenic methane. Near the shelf edge, carbonates are “diluted” with biogenic material produced by reefs—bioherms developed at low sea level stands. Fossil-poor carbonates over salt diapirs of the upper and middle slope formed in the shallow subsurface and have been exhumed by the combined processes of uplift and physical erosion. Middle and lower slope carbonates are generally rich in fossil shells of chemosynthetic organisms. Mg calcite pelloidal matrix and acicular to botryoidal aragonitic void-filling cements are common petrographic features of these hydrocarbonderived carbonates. At two sites carbonates are mixed with barite.

  20. Multiwell CO2 injectivity: impact of boundary conditions and brine extraction on geologic CO2 storage efficiency and pressure buildup.

    Science.gov (United States)

    Heath, Jason E; McKenna, Sean A; Dewers, Thomas A; Roach, Jesse D; Kobos, Peter H

    2014-01-21

    CO2 storage efficiency is a metric that expresses the portion of the pore space of a subsurface geologic formation that is available to store CO2. Estimates of storage efficiency for large-scale geologic CO2 storage depend on a variety of factors including geologic properties and operational design. These factors govern estimates on CO2 storage resources, the longevity of storage sites, and potential pressure buildup in storage reservoirs. This study employs numerical modeling to quantify CO2 injection well numbers, well spacing, and storage efficiency as a function of geologic formation properties, open-versus-closed boundary conditions, and injection with or without brine extraction. The set of modeling runs is important as it allows the comparison of controlling factors on CO2 storage efficiency. Brine extraction in closed domains can result in storage efficiencies that are similar to those of injection in open-boundary domains. Geomechanical constraints on downhole pressure at both injection and extraction wells lower CO2 storage efficiency as compared to the idealized scenario in which the same volumes of CO2 and brine are injected and extracted, respectively. Geomechanical constraints should be taken into account to avoid potential damage to the storage site.

  1. Hydrothermal formation of Co complex oxide and 58Co radioactivity build-up on zircaloy in simulated BWR primary coolant system

    International Nuclear Information System (INIS)

    To explicate deposition and release of Co on fuel cladding in BWR, the hydrothermal formation of spinel type oxide from hydroxide and oxide and Co-58 radioactivity build-up on zircaly has been investigated experimentary in a simulated BWR primary coolant system. (1) The order of reactivity in formation of Co complex oxide from Co(OH)2 was CrO3 > Fe(OH)2 ≥ Cr(OH)3. (2) Compared with Co complex oxide, Ni complex oxide was hard to form. (3) Co-58 radioactivity build-up was practically unaffected by zircaloys with the prior treatment condition. (4) Cr ion was selectively deposited among Fe, Cr, Ni and Co ion on zircaloy test pieces. (author)

  2. A closed-form formulation for the build-up factor and absorbed energy for photons and electrons in the Compton energy range in Cartesian geometry

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Volnei; Vilhena, Marco Tullio, E-mail: borges@ufrgs.b, E-mail: vilhena@pq.cnpq.b [Universidade Federal do Rio Grande do Sul (PROMEC/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Fernandes, Julio Cesar Lombaldo, E-mail: julio.lombaldo@ufrgs.b [Universidade Federal do Rio Grande do Sul (DMPA/UFRGS), Porto Alegre, RS (Brazil). Dept. de Matematica Pura e Aplicada. Programa de Pos Graduacao em Matematica Aplicada

    2011-07-01

    In this work, we report on a closed-form formulation for the build-up factor and absorbed energy, in one and two dimensional Cartesian geometry for photons and electrons, in the Compton energy range. For the one-dimensional case we use the LTS{sub N} method, assuming the Klein-Nishina scattering kernel for the determination of the angular radiation intensity for photons. We apply the two-dimensional LTS{sub N} nodal solution for the averaged angular radiation evaluation for the two-dimensional case, using the Klein-Nishina kernel for photons and the Compton kernel for electrons. From the angular radiation intensity we construct a closed-form solution for the build-up factor and evaluate the absorbed energy. We present numerical simulations and comparisons against results from the literature. (author)

  3. Artifacts in time-resolved NUS: A case study of NOE build-up curves from 2D NOESY

    Science.gov (United States)

    Dass, Rupashree; Kasprzak, Paweł; Koźmiński, Wiktor; Kazimierczuk, Krzysztof

    2016-04-01

    Multidimensional NMR spectroscopy requires time-consuming sampling of indirect dimensions and so is usually used to study stable samples. However, dynamically changing compounds or their mixtures commonly occur in problems of natural science. Monitoring them requires the use multidimensional NMR in a time-resolved manner - in other words, a series of quick spectra must be acquired at different points in time. Among the many solutions that have been proposed to achieve this goal, time-resolved non-uniform sampling (TR-NUS) is one of the simplest. In a TR-NUS experiment, the signal is sampled using a shuffled random schedule and then divided into overlapping subsets. These subsets are then processed using one of the NUS reconstruction methods, for example compressed sensing (CS). The resulting stack of spectra forms a temporal "pseudo-dimension" that shows the changes caused by the process occurring in the sample. CS enables the use of small subsets of data, which minimizes the averaging of the effects studied. Yet, even within these limited timeframes, the sample undergoes certain changes. In this paper we discuss the effect of varying signal amplitude in a TR-NUS experiment. Our theoretical calculations show that the variations within the subsets lead to t1 -noise, which is dependent on the rate of change of the signal amplitude. We verify these predictions experimentally. As a model case we choose a novel 2D TR-NOESY experiment in which mixing time is varied in parallel with shuffled NUS in the indirect dimension. The experiment, performed on a sample of strychnine, provides a near-continuous NOE build-up curve, whose shape closely reflects the t1 -noise level. 2D TR-NOESY reduces the measurement time compared to the conventional approach and makes it possible to verify the theoretical predictions about signal variations during TR-NUS.

  4. Study of the Porosity in Plasma-Sprayed Alumina through an Innovative Three-Dimensional Simulation of the Coating Buildup

    Science.gov (United States)

    Beauvais, S.; Guipont, V.; Jeandin, M.; Jeulin, D.; Robisson, A.; Saenger, R.

    2008-11-01

    Porosity is a key feature of a thermally sprayed coating microstructure. Within ceramic coatings, porosity is made of pores and cracks of various shapes, dimensions, and orientations. Cracks can be intralamellar or interlamellar due to the buildup of the coating, which leads to piled-up lamellae from impinging and the additional rapid solidification of liquid droplets. Pores are interconnected with cracks, which results in a three-dimensional (3-D) porosity network. Direct observation of this network is an intricate task and current attempts remain somewhat limited. A 3-D simulation of this network was, therefore, developed in this work, based on a stochastic approach to the building up of simulated lamellae in the sprayed microstructure. A library of mathematical objects was achieved from morphological measurements, using confocal microscopy of actual isolated flattened lamellae, i.e., “splats” and scanning electron microscopy (SEM). This stochastic approach to the simulation of hundreds of lamellae also involves the random distribution of cracks and pores. Simulation fit parameters were selected according to the overall characteristics of porosity ( i.e., content, orientation, size, etc.) that were determined from the thorough quantitative image analysis (QIA) of cross-sectioned plasma-sprayed alumina coatings. Two plasma modes that varied the atmosphere in a controlled-atmosphere plasma spraying (CAPS) chamber were applied, to produce the microstructures of two different alumina coatings. The 3-D random modeling tool allowed the processing of a volume of digital material through a 3-D simulated binary image of a two-phased composite material. Using one 3-D image result of the simulation, finite element (FE) calculations were performed, in order to study the overall dielectric properties of a plasma-sprayed alumina as a function of porosity. The influence of anisotropy is discussed, in particular, and both analytical and numerical predicted values were

  5. Paleoecological Characteristics of the Carboniferous Phylloid Algal Buildups in Southern Guizhou%贵州南部石炭纪叶状藻礁古生态学特征

    Institute of Scientific and Technical Information of China (English)

    巩恩普; 董旭明; 张永利; 关长庆; 孙宝亮

    2009-01-01

    The Carboniferous phylloid algal buildups are widespread and well exposed in southern Guizhou. A unique depositional sequence consists of phylloid algal buildups, bioclastic banks and mud facies affected by frequent changes of depositional environments. The phylloid algae that grow on the margin of carbonate platform prefer to live in clean water with medium turbulence. Therefore the phylloid algae must be a narrow spectrum of ecological environment. Adjacent two leaves of phylloid algae rarely are tightly together in the growth-form and the spaces between two leaves are often filled with sparry calcite. It indicates that phylloid algae thallus should be a certain tenacity and intensity. The worm may be taked part in the construction of buildup substrate, and they are the pioneer of phylloid algal buildup.%贵州紫云石炭纪叶状藻礁极为发育.叶状藻礁在沉积环境频繁变化作用下,与碎屑滩相、灰泥相共同形成独特的沉积序列.产于碳酸盐岩台地边缘的叶状藻生态适应范围较窄,不能忍受混浊的海水,喜欢清洁动荡中等水动力条件.野外很少见到相邻叶状藻片紧密生长在一起,其间空隙常充填亮晶方解石,表明叶状藻片具有一定的强度和韧性.蠕虫很可能参与了基底的建造,并成为叶状藻礁的先驱.

  6. Diagenesis and Geochemistry of Upper Muschelkalk (Triassic) Buildups and Associated Facies in Catalonia (NE Spain): a paper dedicated to Francesc Calvet

    OpenAIRE

    Tucker, M.; Marshall, J

    2004-01-01

    Carbonate buildups are well developed in the Triassic Upper Muschelkalk of eastern Spain in the La Riba Unit, but they are completely dolomitised. These mud-mounds with reefal caps have well-developed fibrous and botryoidal marine cements which were probably high-Mg calcite and aragonite originally. The dolomite is fabric retentive indicating an early origin, but the d18O values are quite negative (average -3.‰), interpreted as indicating recrystallisation during shallow burial, but without f...

  7. Comparison of build-up region doses in oblique tangential 6 MV photon beams calculated by AAA and CCC algorithms in breast Rando phantom

    Science.gov (United States)

    Masunun, P.; Tangboonduangjit, P.; Dumrongkijudom, N.

    2016-03-01

    The purpose of this study is to compare the build-up region doses on breast Rando phantom surface with the bolus covered, the doses in breast Rando phantom and also the doses in a lung that is the heterogeneous region by two algorithms. The AAA in Eclipse TPS and the collapsed cone convolution algorithm in Pinnacle treatment planning system were used to plan in tangential field technique with 6 MV photon beam at 200 cGy total doses in Breast Rando phantom with bolus covered (5 mm and 10 mm). TLDs were calibrated with Cobalt-60 and used to measure the doses in irradiation process. The results in treatment planning show that the doses in build-up region and the doses in breast phantom were closely matched in both algorithms which are less than 2% differences. However, overestimate of doses in a lung (L2) were found in AAA with 13.78% and 6.06% differences at 5 mm and 10 mm bolus thickness, respectively when compared with CCC algorithm. The TLD measurements show the underestimate in buildup region and in breast phantom but the doses in a lung (L2) were overestimated when compared with the doses in the two plannings at both thicknesses of the bolus.

  8. Monte Carlo correction factors for a Farmer 0.6 cm3 ion chamber dose measurement in the build-up region of the 6 MV clinical beam.

    Science.gov (United States)

    Pena, J; Sánchez-Doblado, F; Capote, R; Terrón, J A; Gómez, F

    2006-03-21

    Reference dosimetry of photon fields is a well-established subject and currently available protocols (such as the IAEA TRS-398 and AAPM TG-51) provide methods for converting the ionization chamber (IC) reading into dose to water, provided reference conditions of charged particle equilibrium (CPE) are fulfilled. But these protocols cannot deal with the build-up region, where the lack of CPE limits the applicability of the cavity theorems and so the chamber correction factors become depth dependent. By explicitly including the IC geometry in the Monte Carlo simulations, depth-dependent dose correction factors are calculated for a PTW 30001 0.6 cm(3) ion chamber in the build-up region of the 6 MV photon beam. The corrected percentage depth dose (PDD) agrees within 2% with that measured using the NACP 02 plane-parallel ion chamber in the build-up region at depths greater than 0.4 cm, where the Farmer chamber wall reaches the phantom surface. PMID:16510960

  9. Surface and buildup region dose measurements with Markus parallel-plate ionization chamber, Gafchromic EBT3 film and MOSFET detector for high energy photon beams

    CERN Document Server

    Akbas, Ugur; Koksal, Canan; Bilge, Hatice

    2016-01-01

    The aim of the study was to investigate surface and buildup region doses for 6 MV photon beams using a Markus parallel-plate ionization chamber, GafChromic EBT3 film and MOSFET detector for different field sizes and beam angles. The measurements were made in a water equivalent solid phantom at the surface and in the buildup region of the 6 MV photon beams at 100 cm source-detector distance (SDD) for 5x5, 10x10 and 20x20 cm2 field sizes and 0, 30, 60, 80 and 90 beam angles. The surface doses for 10x10 cm2 field size were found to be 20.33%, 18.80% and 25.48% for Markus chamber, EBT3 film and MOSFET detector, respectively. The surface dose increased with field size for all dosimeters. As the angle of the incident radiation beam became more oblique, the surface dose increased. The effective measurement depths of dosimeters vary, thus the results of the measurements could be different. This issue can lead to mistakes at surface and buildup dosimetry, and must be taken into account.

  10. Eumelanin buildup on the nanoscale: aggregate growth/assembly and visible absorption development in biomimetic 5,6-dihydroxyindole polymerization.

    Science.gov (United States)

    Arzillo, Marianna; Mangiapia, Gaetano; Pezzella, Alessandro; Heenan, Richard K; Radulescu, Aurel; Paduano, Luigi; d'Ischia, Marco

    2012-08-13

    Establishing structure-property relationships in the black insoluble eumelanins, the key determinants of human pigmentation and skin photoprotective system, is a considerable conceptual and experimental challenge in the current drive for elucidation of the biological roles of these biopolymers and their application as advanced materials for organoelectronics. Herein, we report a new breakthrough toward this goal by the first detailed investigation on the nanoscale level of the oxidative polymerization of 5,6-dihydroxyindole (DHI), a model process of eumelanin synthesis. On the basis of a combined use of spectrophotometry, dynamic light scattering (DLS), and small-angle neutron scattering (SANS) investigations, it was possible to unveil the dynamics of the aggregation process before precipitation, the key relationships with visible light absorption and the shape of fundamental aggregates. The results indicated a polymerization mechanism of the type: Polymer(n) + DHI(x) = Polymer(n+x), where DHI(x) indicates monomer, dimer, or low oligomers (x ≤ 5). During polymerization, visible absorption increases rapidly, reaching a plateau. Particle growth proceeds slowly, with formation of 2-D structures ~55 nm thick, until precipitation occurs, that is, when large aggregates with a maximum hydrodynamic radius (R(h)) of ~1200 nm are formed. Notably, markedly smaller R(h) values, up to ~110 nm, were determined in the presence of poly(vinyl alcohol) (PVA) that was shown to be an efficient aggregation-preventing agent for polymerizing DHI ensuring water solubilization. Finally, it is shown that DHI monomer can be efficiently and partially irreversibly depleted from aqueous solutions by the addition of eumelanin suspensions. This behavior is suggested to reflect oxidant-independent competing pathways of polymer synthesis and buildup via monomer conversion on the active aggregate surface contributing to particle growth. Besides filling crucial gaps in DHI polymerization, these

  11. A comprehensive interpretation of the NEEM basal ice build-up using a multi-parametric approach

    Science.gov (United States)

    Goossens, Thomas; Sapart, Célia J.; Dahl-Jensen, Dorthe; Popp, Trevor; El Amri, Saïda; Tison, Jean-Louis

    2016-03-01

    stratified debris-rich layers and the ice containing dispersed debris layers respectively express an "open" or "closed" system melting/refreezing signature, somewhat blurred by mixing processes in the upper part of the sequence. Climatic reconstruction is therefore prohibited from these ice types. We propose a first interpretative framework for the build-up of the NEEM basal ice sequence, based on the origin of the various ice types.

  12. Eumelanin buildup on the nanoscale: aggregate growth/assembly and visible absorption development in biomimetic 5,6-dihydroxyindole polymerization.

    Science.gov (United States)

    Arzillo, Marianna; Mangiapia, Gaetano; Pezzella, Alessandro; Heenan, Richard K; Radulescu, Aurel; Paduano, Luigi; d'Ischia, Marco

    2012-08-13

    Establishing structure-property relationships in the black insoluble eumelanins, the key determinants of human pigmentation and skin photoprotective system, is a considerable conceptual and experimental challenge in the current drive for elucidation of the biological roles of these biopolymers and their application as advanced materials for organoelectronics. Herein, we report a new breakthrough toward this goal by the first detailed investigation on the nanoscale level of the oxidative polymerization of 5,6-dihydroxyindole (DHI), a model process of eumelanin synthesis. On the basis of a combined use of spectrophotometry, dynamic light scattering (DLS), and small-angle neutron scattering (SANS) investigations, it was possible to unveil the dynamics of the aggregation process before precipitation, the key relationships with visible light absorption and the shape of fundamental aggregates. The results indicated a polymerization mechanism of the type: Polymer(n) + DHI(x) = Polymer(n+x), where DHI(x) indicates monomer, dimer, or low oligomers (x ≤ 5). During polymerization, visible absorption increases rapidly, reaching a plateau. Particle growth proceeds slowly, with formation of 2-D structures ~55 nm thick, until precipitation occurs, that is, when large aggregates with a maximum hydrodynamic radius (R(h)) of ~1200 nm are formed. Notably, markedly smaller R(h) values, up to ~110 nm, were determined in the presence of poly(vinyl alcohol) (PVA) that was shown to be an efficient aggregation-preventing agent for polymerizing DHI ensuring water solubilization. Finally, it is shown that DHI monomer can be efficiently and partially irreversibly depleted from aqueous solutions by the addition of eumelanin suspensions. This behavior is suggested to reflect oxidant-independent competing pathways of polymer synthesis and buildup via monomer conversion on the active aggregate surface contributing to particle growth. Besides filling crucial gaps in DHI polymerization, these

  13. Precipitation dominates fire occurrence in Greece (1900-2010): its dual role in fuel build-up and dryness

    Science.gov (United States)

    Xystrakis, F.; Kallimanis, A. S.; Dimopoulos, P.; Halley, J. M.; Koutsias, N.

    2014-01-01

    Historical fire records and meteorological observations spanning over one century (1894-2010) were assembled in a database to collect long-term fire and weather data in Greece. Positive/negative events of fire occurrence on an annual basis were considered as the years where the annual values of the examined parameters were above (positive values) or below (negative values) the 95% confidence limits around the trend line of the corresponding parameter. To analyse the association of positive/negative events of fire occurrence with meteorological extremes, we proceeded with a cross-tabulation analysis based on a Monte Carlo randomization. Positive/negative values of total annual precipitation were randomly associated with the corresponding values of burned areas, and significant associations were observed for seasonal precipitation totals (spring and fire season). Fire season precipitation is the dominant factor coinciding with negative values of area burned, while years with high spring precipitation coincide with years with large areas burned. These results demonstrate the dual role of precipitation in controlling a fire's extent through fuel build-up and dryness. Additionally, there is a clear outperformance of precipitation-related variables compared with temperature-related weather revealing that, at least in Greece, total area burned at the national scale is controlled by precipitation totals rather than air temperature. This analysis improves our understanding of the underlying mechanisms of fire regimes and provides valuable information concerning the development of models relating fire activity to weather parameters, which are essential when facing a changing climate that may be associated with shifts in various aspects of the typical fire regimes of ecosystems. Our results may allow fire managers to more easily incorporate the effect of extreme weather conditions into long-term planning strategies. They contribute to the exploration of fire

  14. Surface and Buildup Region Dose Measurements with Markus Parallel-Plate Ionization Chamber, GafChromic EBT3 Film, and MOSFET Detector for High-Energy Photon Beams

    Directory of Open Access Journals (Sweden)

    Ugur Akbas

    2016-01-01

    Full Text Available The aim of the study was to investigate surface and buildup region doses for 6 MV and 15 MV photon beams using a Markus parallel-plate ionization chamber, GafChromic EBT3 film, and MOSFET detector for different field sizes and beam angles. The measurements were made in a water equivalent solid phantom at the surface and in the buildup region of the 6 MV and 15 MV photon beams at 100 cm source-detector distance for 5 × 5, 10 × 10, and 20 × 20 cm2 field sizes and 0°, 30°, 60°, and 80° beam angles. The surface doses using 6 MV photon beams for 10 × 10 cm2 field size were found to be 20.3%, 18.8%, and 25.5% for Markus chamber, EBT3 film, and MOSFET detector, respectively. The surface doses using 15 MV photon beams for 10 × 10 cm2 field size were found to be 14.9%, 13.4%, and 16.4% for Markus chamber, EBT3 film, and MOSFET detector, respectively. The surface dose increased with field size for all dosimeters. As the angle of the incident radiation beam became more oblique, the surface dose increased. The effective measurement depths of dosimeters vary; thus, the results of the measurements could be different. This issue can lead to mistakes at surface and buildup dosimetry and must be taken into account.

  15. 关于政务公开理念建构的思考%Considerations on Buildup the Concept of Open Government

    Institute of Scientific and Technical Information of China (English)

    王运萍

    2012-01-01

    The concept is of extraordinary power.Open government is the behavior of the governments' administration,which needs not only to build the dams of the system,but also to build moral embankment.The significance of buildup the concepts is well highlighted in the dialectical relationship between the concept and the operations and systems(the rule by law).To achieve effective results in the open government the buildup of the concept of the right to know,of mutually beneficial win-win,of good governance of society,and of flexible treatment is critical.%理念的力量意义非凡,政务公开是政府的治理行为,不但要修筑制度的大坝,更要建构道德的堤岸,理念建构的意义在它与行动和制度(法治)之间的辩证关系中得到了很好的凸显。政务公开要取得实效,知情权理念、双赢互利理念、社会善治理念、柔性处理理念的建构至为关键。

  16. Evolutionary paths among different red galaxy types at 0.3 < z < 1.5 and the build-up of massive E-S0's

    Science.gov (United States)

    Gallego, Jesús; Prieto, Mercedes; Eliche-Moral, M. Carmen; Balcells, Marc; Cristóbal-Hornillos, David; Erwin, Peter; Abreu, David; Domínguez-Palmero, Lilian; Hempel, Angela; López-Sanjuan, Carlos; Guzmán, Rafael; Pérez-González, Pablo G.; Barro, Guillermo; Zamorano, Jaime

    2013-07-01

    Some recent observations seem to disagree with hierarchical theories of galaxy formation on the role of major mergers in a late build-up of massive early-type galaxies. We re-address this question by analysing the morphology, structural distortion level, and star formation enhancement of a sample of massive galaxies (M* > 5 × 1010M⊙) lying on the Red Sequence and its surroundings at 0.3 1011M⊙ at z = 0 through gas-rich major mergers has frozen since z ~ 0.6. Our results support that major mergers have played the dominant role in the definitive build-up of present-day E-S0's with M* > 1011M⊙ at 0.6 Spanish Ministry of Science and Innovation (MICINN) under projects AYA2009-10368, AYA2006-12955, AYA2010-21887-C04-04, and AYA2009-11137, by the Madrid Regional Government through the AstroMadrid Project (CAM S2009/ESP-1496), and by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: ``First Science with the GTC'' (http://www.iac.es/consolider-ingenio-gtc/). S. D. H. & G.

  17. Suspension-firing of wood with coal ash addition: Probe measurements of ash deposit build-up at Avedøre Power Plant (AVV2)

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Jappe Frandsen, Flemming;

    This report is about full-scale probe measurements of deposit build-up and removal conducted at the Avedøreværket Unit 2, a 800 MWth suspension boiler, firing wood and natural gas with the addition of coal ash. Coal ash was used as an additive to capture potassium (K) from wood-firing. Investigat......This report is about full-scale probe measurements of deposit build-up and removal conducted at the Avedøreværket Unit 2, a 800 MWth suspension boiler, firing wood and natural gas with the addition of coal ash. Coal ash was used as an additive to capture potassium (K) from wood......-firing. Investigations of deposit formation rate were made by use of an advanced online ash deposition/shedding probe. Quantification of ash deposition and shedding was made via deposit mass uptake signals obtained from the deposit probe. The influence of coal ash, flue gas temperature, probe surface temperature...... oC), deposit removal through surface melting was not identified. SEM-EDS analysis of the deposits showed significant presence of Ca, Al and Si, indicating that a significant amount of K has been captured by coal ash to form deposits rich in calcium-aluminum-silicates, and possible release of Cl...

  18. Characterization of 2 MeV, 4 MeV, 6 MeV and 18 MeV buildup caps for use with a 0.6 cubic centimeter thimble ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Salyer, R.L.; VanDenburg, J.W.; Prinja, A.K.; Kirby, T.; Busch, R. [Univ. of New Mexico, Albuquerque, NM (United States); Hong-Nian Jow [Sandia National Laboratories, Albuquerque, NM (United States)

    1996-07-01

    The purpose of this research is to characterize existing 2 MeV, 4 MeV and 6 MeV buildup caps, and to determine if a buildup cap can be made for the 0.6 cm{sup 3} thimble ionization chamber that will accurately measure exposures in a high-energy photon radiation field. Two different radiation transport codes were used to computationally characterize existing 2 MeV, 4 MeV, and 6 MeV buildup caps for a 0.6 cm{sup 3} active volume thimble ionization chamber: ITS, The Integrated TIGER Series of Coupled Electron-Photon Monte Carlo Transport Codes; and CEPXS/ONEDANT, A One-Dimensional Coupled Electron-Photon Discrete Ordinates Code Package. These codes were also used to determine the design characteristics of a buildup cap for use in the 18 MeV photon beam produced by the 14 TW pulsed power HERMES-III electron accelerator. The maximum range of the secondary electron, the depth at which maximum dose occurs, and the point where dose and collision kerma are equal have been determined to establish the validity of electronic equilibrium. The ionization chamber with the appropriate buildup cap was then subjected to a 4 MeV and a 6 MeV bremmstrahlung radiation spectrum to determine the detector response.

  19. Together, slowly but surely: the role of social interaction and feedback in the build-up of benefit in collective decision-making

    DEFF Research Database (Denmark)

    Bahrami, Bahador; Olsen, Karsten; Bang, Dan;

    2011-01-01

    asked if social interaction and objective reference contribute differently to the formation and build-up of collective perceptual beliefs. In three experiments, dyads made individual and collective perceptual decisions in a two-interval, forced-choice, visual search task. In Experiment 1, participants...... negotiated their collective decisions with each other verbally and received feedback about accuracy at the end of each trial. In Experiment 2, feedback was not given. In Experiment 3, communication was not allowed but feedback was provided. Social interaction (Experiments 1 and 2 vs. 3) resulted...... in a significant collective benefit in perceptual decisions. When feedback was not available a collective benefit was not initially obtained but emerged through practice to the extent that in the second half of the experiments, collective benefits obtained with (Experiment 1) and without (Experiment 2) feedback...

  20. Effects of salinity build-up on the performance of an anaerobic membrane bioreactor regarding basic water quality parameters and removal of trace organic contaminants.

    Science.gov (United States)

    Song, Xiaoye; McDonald, James; Price, William E; Khan, Stuart J; Hai, Faisal I; Ngo, Hao H; Guo, Wenshan; Nghiem, Long D

    2016-09-01

    The effects of elevated inorganic salt concentration on anaerobic membrane bioreactor (AnMBR) treatment regarding basic biological performance and trace organic contaminant (TrOC) removal were investigated. A set of 33 TrOCs were selected to represent pharmaceuticals, steroids, and pesticides in municipal wastewater. Results show potential adverse effects of increase in the bioreactor salinity to 15g/L (as NaCl) on the performance of AnMBR with respect to chemical oxygen demand removal, biogas production, and the removal of most hydrophilic TrOCs. Furthermore, a decrease in biomass production was observed as salinity in the bioreactor increased. The removal of most hydrophobic TrOCs was high and was not significantly affected by salinity build-up in the bioreactor. The accumulation of a few persistent TrOCs in the sludge phase was observed, but such accumulation did not vary significantly as salinity in the bioreactor increased. PMID:27262094

  1. Time-resolved Shielded-Pickup Measurements and Modeling of Beam Conditioning Effects on Electron Cloud Buildup at CesrTA

    CERN Document Server

    Crittenden, J A; Liu, X; Palmer, M A; Santos, S; Sikora, J P; Kato, S; Calatroni, S; Rumolo, G

    2012-01-01

    The Cornell Electron Storage Ring Test Accelerator program includes investigations into electron cloud buildup in vacuum chambers with various coatings. Two 1.1-mlong sections located symmetrically in the east and west arc regions are equipped with BPM-like pickup detectors shielded against the direct beam-induced signal. They detect cloud electrons migrating through an 18-mm-diameter pattern of 0.76 mm-diameter holes in the top of the chamber. A digitizing oscilloscope is used to record the signals, providing time-resolved information on cloud development. We present new measurements of the effect of beam conditioning on a newly-installed amorphous carbon coated chamber, as well as on an extensively conditioned chamber with a diamond-like carbon coating. The ECLOUD modeling code is used to quantify the sensitivity of these measurements to model parameters, differentiating between photoelectron and secondary-electron production processes.

  2. Study of the effect of external heating and internal temperature build-up during polymerization on the morphology of porous polymethacrylate adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Chan Yi, E-mail: vicchanyiwei@hotmail.com; Ongkudon, Clarence M., E-mail: clarence@ums.edu.my; Kansil, Tamar, E-mail: tamarkansil87@gmail.com [Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah (Malaysia)

    2015-07-22

    Modern day synthesis protocols of methacrylate monolithic polymer adsorbent are based on existing polymerization blueprint without a thorough understanding of the dynamics of pore structure and formation. This has resulted in unproductiveness of polymer adsorbent consequently affecting purity and recovery of final product, productivity, retention time and cost effectiveness of the whole process. The problems magnified in monolith scaling-up where internal heat buildup resulting from external heating and high exothermic polymerization reaction was reflected in cracking of the adsorbent. We believe that through careful and precise control of the polymerization kinetics and parameters, it is possible to prepare macroporous methacrylate monolithic adsorbents with controlled pore structures despite being carried out in an unstirred mould. This research involved the study of the effect of scaling-up on pore morphology of monolith, in other words, porous polymethacrylate adsorbents that were prepared via bulk free radical polymerization process by imaging the porous morphology of polymethacrylate with scanning electron microscope.

  3. Study of Diagenetic Features in Rudist Buildups of Cretaceous Edwards Formation Using Ground Based Hyperspectral Scanning and Terrestrial LiDAR

    Science.gov (United States)

    Krupnik, D.; Khan, S.; Okyay, U.; Hartzell, P. J.; Biber, K.

    2015-12-01

    Ground based remote sensing is a novel technique for development of digital outcrop models which can be instrumental in performing detailed qualitative and quantitative sedimentological analysis for the study of depositional environment, diagenetic processes, and hydrocarbon reservoir characterization. For this investigation, ground-based hyperspectral data collection is combined with terrestrial LiDAR to study outcrops of Late Albian rudist buildups of the Edwards formation in the Lake Georgetown Spillway in Williamson County, Texas. The Edwards formation consists of shallow water deposits of reef and associated inter-reef facies, including rudist bioherms and biostromes. It is a significant aquifer and was investigated as a hydrocarbon play in south central Texas. Hyperspectral data were used to map compositional variation in the outcrop by distinguishing spectral properties unique to each material. Lithological variation was mapped in detail to investigate the structure and composition of rudist buildups. Hyperspectral imagery was registered to a 3D model produced from the LiDAR point cloud with an accuracy of up to one pixel. Flat-topped toucasid-rich bioherm facies were distinguished from overlying toucasid-rich biostrome facies containing chert nodules, overlying sucrosic dolostones, and uppermost peloid wackestones and packstones of back-reef facies. Ground truth was established by petrographic study of samples from this area and has validated classification products of remote sensing data. Several types of porosity were observed and have been associated with increased dolomitization. This ongoing research involves integration of remotely sensed datasets to analyze geometrical and compositional properties of this carbonate formation at a finer scale than traditional methods have achieved and seeks to develop a workflow for quick and efficient ground based remote sensing-assisted outcrop studies.

  4. SU-E-J-239: Influence of RF Coil Materials On Surface and Buildup Dose From a 6MV Photon Beam

    International Nuclear Information System (INIS)

    Purpose: In order to perform real time tumour tracking using an integrated Linac-MR, images have to be acquired during irradiation. MRI uses RF coils in close proximity to the imaged volume. Given current RF coil designs this means that the high energy photons will be passing through the coil before reaching the patient. This study experimentally investigates the dose modifications that occur due to the presence of various RF coil materials in the treatment beam. Methods: Polycarbonate, copper or aluminum tape, and Teflon were used to emulate the base, conductor and cover respectively of a surface RF coil. These materials were placed at various distances from the surface of polystyrene or solid water phantoms which were irradiated in the presence of no magnetic field, a transverse 0.2T magnetic field, and a parallel 0.2T magnetic field. Percent depth doses were measured using ion chambers. Results: A significant increase in surface and buildup dose is observed. The surface dose is seen to decrease with an increasing separation between the emulated coil and the phantom surface, when no magnetic field is present. When a transverse magnetic field is applied the surface dose decreases faster with increasing separation, as some of the electrons created in the coil are curved away from the phantom’s surface. When a parallel field is present the surface dose stays approximately constant for small separations, only slightly decreasing for separations greater than 5cm, since the magnetic field focuses the electrons produced in the coil materials not allowing them to scatter. Conclusion: Irradiating a patient through an RF coil leads to an increase in the surface and buildup doses. Mitigating this increase is important for the successful clinical use of either a transverse or a parallel configuration Linac-MR unit. This project is partially supported by an operating grant from the Canadian Institute of Health Research (CIHR MOP 93752)

  5. SU-E-J-239: Influence of RF Coil Materials On Surface and Buildup Dose From a 6MV Photon Beam

    Energy Technology Data Exchange (ETDEWEB)

    Ghila, A; Fallone, B; Rathee, S [Cross Cancer Institute, Edmonton, AB (United Kingdom)

    2015-06-15

    Purpose: In order to perform real time tumour tracking using an integrated Linac-MR, images have to be acquired during irradiation. MRI uses RF coils in close proximity to the imaged volume. Given current RF coil designs this means that the high energy photons will be passing through the coil before reaching the patient. This study experimentally investigates the dose modifications that occur due to the presence of various RF coil materials in the treatment beam. Methods: Polycarbonate, copper or aluminum tape, and Teflon were used to emulate the base, conductor and cover respectively of a surface RF coil. These materials were placed at various distances from the surface of polystyrene or solid water phantoms which were irradiated in the presence of no magnetic field, a transverse 0.2T magnetic field, and a parallel 0.2T magnetic field. Percent depth doses were measured using ion chambers. Results: A significant increase in surface and buildup dose is observed. The surface dose is seen to decrease with an increasing separation between the emulated coil and the phantom surface, when no magnetic field is present. When a transverse magnetic field is applied the surface dose decreases faster with increasing separation, as some of the electrons created in the coil are curved away from the phantom’s surface. When a parallel field is present the surface dose stays approximately constant for small separations, only slightly decreasing for separations greater than 5cm, since the magnetic field focuses the electrons produced in the coil materials not allowing them to scatter. Conclusion: Irradiating a patient through an RF coil leads to an increase in the surface and buildup doses. Mitigating this increase is important for the successful clinical use of either a transverse or a parallel configuration Linac-MR unit. This project is partially supported by an operating grant from the Canadian Institute of Health Research (CIHR MOP 93752)

  6. The influence of modified water chemistries on metal oxide films, activity build-up and stress corrosion cracking of structural materials in nuclear power plants

    International Nuclear Information System (INIS)

    The primary coolant oxidises the surfaces of construction materials in nuclear power plants. The properties of the oxide films influence significantly the extent of incorporation of actuated corrosion products into the primary circuit surfaces, which may cause additional occupational doses for the maintenance personnel. The physical and chemical properties of the oxide films play also an important role in different forms of corrosion observed in power plants. This report gives a short overview of the factors influencing activity build-up and corrosion phenomena in nuclear power plants. Furthermore, the most recent modifications in the water chemistry to decrease these risks are discussed. A special focus is put on zinc water chemistry, and a preliminary discussion on the mechanism via which zinc influences activity build-up is presented. Even though the exact mechanisms by which zinc acts are not yet known, it is assumed that Zn may block the diffusion paths within the oxide film. This reduces ion transport through the oxide films leading to a reduced rate of oxide growth. Simultaneously the number of available adsorption sites for 60Co is also reduced. The current models for stress corrosion cracking assume that the anodic and the respective cathodic reactions contributing to crack growth occur partly on or in the oxide films. The rates of these reactions may control the crack propagation rate and therefore, the properties of the oxide films play a crucial role in determining the susceptibility of the material to stress corrosion cracking. Finally, attention is paid also on the novel techniques which can be used to mitigate the susceptibility of construction materials to stress corrosion cracking. (orig.)

  7. METHODS FOR PALEO-FLUID PRESSURE BUILD-UP IN BASINS%盆地中古流体压力的恢复方法

    Institute of Scientific and Technical Information of China (English)

    王爱国

    2011-01-01

    为了优化古流体压力恢复的技术途径,结合国内外的研究进展对盆地中古流体压力的恢复方法进行了梳理、分析和讨论.恢复方法主要包括泥岩声波时差法、盆地模拟法和流体包裹体法.泥岩声波时差法廉价、快速,但只能恢复最大埋深时的古流体压力,而不适于欠压实以外其他异常压力形成机制;盆地模拟方法可恢复压力的演化史,但其地质模型复杂、参数繁多且不确定性较强,结果的准确度较低;流体包裹体法不必考虑复杂的地质历史和压力形成机制,但目前在绝多数情况下获得的是均一压力或最小捕获压力.进一步研究盐水包裹体的等容线,可提高古流体压力的准确度.每种恢复方法都有其优缺点,对其局限性进行了重点讨论,并指出了发展方向.%In order to optimize the technical methods of paleo-fluid pressure build-up, the methods for paleo-fluid build-up in basins are sorted out, compared, analyzed and discussed based on the research progresses at home and abroad. The build-up methods mainly include mudstone acoustic travel time method, basin modeling method and fluid inclusion method. Mudstone acoustic travel time method is cheap and rapid. However, it can only recover the paleo-fluid pressure at the maximum burial depth, and it is not suitable for other abnormal pressure formation mechanism except for uncompaction. Basin modeling method can recover the evolutionary history. But in this method, its geological model is complex and has many parameters, moreover many of which have relatively high uncertainty, therefore the accuracy of result obtained by this method is relatively low. Fluid inclusion method can get paleo-fluid pressure without considering the complex geologic history and pressure formation mechanism. However, in most cases ,this method can only obtain homogeneous pressure or minimum trapping pressure at present. The further study on isometric line of saline

  8. HETEROGENEOUS SHALLOW-SHELF CARBONATE BUILDUPS IN THE PARADOX BASIN, UTAH AND COLORADO: TARGETS FOR INCREASED OIL PRODUCTION AND RESERVES USING HORIZONTAL DRILLING TECHNIQUES

    Energy Technology Data Exchange (ETDEWEB)

    David E. Eby; Thomas C. Chidsey, Jr.; Kevin McClure; Craig D. Morgan

    2003-07-01

    The Paradox Basin of Utah, Colorado, Arizona, and New Mexico contains nearly 100 small oil fields producing from carbonate buildups within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to 10 wells with primary production ranging from 700,000 to 2,000,000 barrels (111,300-318,000 m{sup 3}) of oil per field and a 15 to 20 percent recovery rate. At least 200 million barrels (31.8 million m{sup 3}) of oil will not be recovered from these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Several fields in southeastern Utah and southwestern Colorado are being evaluated as candidates for horizontal drilling and enhanced oil recovery from existing vertical wells based upon geological characterization and reservoir modeling case studies. Geological characterization on a local scale is focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible reservoir compartmentalization, within these fields. This study utilizes representative cores, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells. The results of these studies can be applied to similar fields elsewhere in the Paradox Basin and the Rocky Mountain region, the Michigan and Illinois Basins, and the Midcontinent region. This report covers research activities for the second half of the third project year (October 6, 2002, through April 5, 2003). The primary work included describing and mapping regional facies of the upper Ismay and lower Desert Creek zones of the Paradox Formation in the Blanding sub-basin, Utah. Regional cross sections show the development of ''clean carbonate'' packages that contain all of the productive reservoir facies. These clean carbonates abruptly change laterally into thick anhydrite packages that filled several small intra-shelf basins in the upper Ismay zone

  9. Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp

    International Nuclear Information System (INIS)

    We present simulation results of the build-up of the electron-cloud density ne in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range Nt = (2-5) x 1013, and the beam kinetic energy in the range Ek = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) (delta)max vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed Nt there is a clear threshold behavior of ne as a function of (delta)max in the range ∼ 1.1-1.3. (2) At fixed (delta)max, there is a threshold behavior of ne as a function of Nt provided (delta)max is sufficiently high; the threshold value of Nt is a function of the characteristics of the region being simulated. (3) The dependence on Ek is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.

  10. A theoretical study of the build-up of the Sun's polar magnetic field by using a 3D kinematic dynamo model

    CERN Document Server

    Hazra, Gopal; Miesch, Mark S

    2016-01-01

    We develop a three-dimensional kinematic self-sustaining model of the solar dynamo in which the poloidal field generation is from tilted bipolar sunspot pairs placed on the solar surface above regions of strong toroidal field by using the SpotMaker algorithm and then the transport of this poloidal field to the tachocline is primarily caused by turbulent diffusion. We obtain a dipolar solution within a certain range of parameters. We use this model to study the build-up of the polar magnetic field and show that some insights obtained from surface flux transport (SFT) models have to be revised. We present results obtained by putting a single bipolar sunspot pair in a hemisphere and two symmetrical sunspot pairs in two hemispheres. We find that the polar fields produced by them disappear due to subduction by the meridional circulation sinking underneath the surface in the polar region, which is not included in the SFT models. We also study the effect that a large sunspot pair violating Hale's polarity law would ...

  11. Build-up of an antimicrobial multilayer coating on a textile support based on a methylene blue–poly(cyclodextrin) complex

    International Nuclear Information System (INIS)

    The aim of this work was to develop an antibacterial multilayer coating activated with methylene blue (MB) and based on chitosan (CHT) and cyclodextrin polyelectrolyte (polyCD) onto a non-woven polyethylene terephthalate (PET) textile support. The MB-free and MB-loaded systems were built-up by applying the dip-coating technique, alternating soak cycles of the PET textile preliminarily modified with carboxylate groups in CHT and in polyCD or polyCD/MB complex solutions. The layer-by-layer assembly build-up was followed by optical waveguide lightmode spectroscopy on the one hand and by gravimetry once it was applied on the textile substrate on the other hand. Two chitosan grades were used, low molecular weight (CHT-L) and medium molecular weight (CHT-M). The influence of the molar ratio CD/MB in the polyCD solutions was varied and finally the system underwent a post reticulation with genipin. Such parameters influences were investigated with regard to the loading capacity in MB of the systems, the release kinetics profiles of MB in pure water, phosphate buffer and MEM media, and the degradation of the self-assembled coating in the same media. Finally, biological and microbiological tests were performed to demonstrate the cytocompatibility of the systems and their ability to display a sustained antibacterial effect of the device through the MB prolonged release. (paper)

  12. Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M. A.

    2010-12-11

    We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.

  13. The coordinated key role of wet, mixed, and dry major mergers in the buildup of massive early-type galaxies at z<~1

    CERN Document Server

    Eliche-Moral, M Carmen; Gallego, Jesus; Zamorano, Jaime

    2010-01-01

    Hierarchical models predict that massive early-type galaxies (mETGs) derive from the most massive and violent merging sequences occurred in the Universe. However, the role of wet, mixed, and dry major mergers in the assembly of mETGs is questioned by some recent observations. We have developed a semi-analytical model to test the feasibility of the major-merger origin hypothesis for mETGs, just accounting for the effects on galaxy evolution of the major mergers strictly reported by observations. The model proves that it is feasible to reproduce the observed number density evolution of mETGs since z~1, just accounting for the coordinated effects of wet/mixed/dry major mergers. It can also reconcile the different assembly redshifts derived by hierarchical models and by mass downsizing data for mETGs, just considering that a mETG observed at a certain redshift is not necessarily in place since then. The model predicts that wet major mergers have controlled the mETGs buildup since z~1, although dry and mixed merge...

  14. Evolutionary paths among different red galaxy types at 0.3 < z < 1.5 and the late buildup of massive E-S0's through major mergers

    CERN Document Server

    Prieto, Mercedes; Balcells, Marc; Cristobal-Hornillos, David; Erwin, Peter; Abreu, David; Dominguez-Palmero, Lilian; Hempel, Angela; Lopez-Sanjuan, Carlos; Guzman, Rafael; Perez-Gonzalez, Pablo G; Barro, Guillermo; Gallego, Jesus; Zamorano, Jaime

    2012-01-01

    Some recent observations seem to disagree with hierarchical theories of galaxy formation about the role played by major mergers in the late buildup of massive E-S0's. We re-address this question by analysing the morphology, structural distortion level, and star formation enhancement of a sample of massive galaxies (M_* > 5 * 10^10 Msun) lying on the Red Sequence and its surroundings at 0.3 10^11 Msun at z=0 through gas-rich major mergers has frozen since z~0.6. All these facts support that major mergers have played the dominant role in the definitive buildup of present-day E-S0's with M_*> 10^11 Msun at 0.6

  15. Trace organic solutes in closed-loop forward osmosis applications: influence of membrane fouling and modeling of solute build-up.

    Science.gov (United States)

    D'Haese, Arnout; Le-Clech, Pierre; Van Nevel, Sam; Verbeken, Kim; Cornelissen, Emile R; Khan, Stuart J; Verliefde, Arne R D

    2013-09-15

    In this study, trace organics transport in closed-loop forward osmosis (FO) systems was assessed. The FO systems considered, consisted of an FO unit and a nanofiltration (NF) or reverse osmosis (RO) unit, with the draw solution circulating between both units. The rejection of trace organics by FO, NF and RO was tested. It was found that the rejection rates of FO were generally comparable with NF and lower than RO rejection rates. To assess the influence of fouling in FO on trace organics rejection, FO membranes were fouled with sodium alginate, bovine serum albumin or by biofilm growth, after which trace organics rejection was tested. A negative influence of fouling on FO rejection was found which was limited in most cases, while it was significant for some compounds such as paracetamol and naproxen, indicating specific compound-foulant interactions. The transport mechanism of trace organics in FO was tested, in order to differentiate between diffusive and convective transport. The concentration of trace organics in the final product water and the build-up of trace organics in the draw solution were modeled assuming the draw solution was reconcentrated by NF/RO and taking into account different transport mechanisms for the FO membrane and different rejection rates by NF/RO. Modeling results showed that if the FO rejection rate is lower than the RO rejection rate (as is the case for most compounds tested), the added value of the FO-RO cycle compared to RO only at steady-state was small for diffusively and negative for convectively transported trace organics. Modeling also showed that trace organics accumulate in the draw solution.

  16. Build-ups in the supply chain of the brain: on the neuroenergetic cause of obesity and type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Achim Peters

    2009-04-01

    Full Text Available Obesity and type 2 diabetes have become the major health problems in many industrialized countries. A few theoretical frameworks have been set up to derive the possible determinative cause of obesity. One concept views that food availability determines food intake, i.e. that obesity is the result of an external energy “push” into the body. Another one views that the energy milieu within the human organism determines food intake, i.e. that obesity is due to an excessive “pull” from inside the organism. Here we present the unconventional concept that a healthy organism is maintained by a „competent brain-pull“ which serves systemic homeostasis, and that the underlying cause of obesity is “incompetent brain-pull”, i.e. that the brain is unable to properly demand glucose from the body. We describe the energy fluxes from the environment, through the body, towards the brain with a mathematical “supply chain” model and test whether its predictions fit medical and experimental data sets from our and other research groups. In this way, we show data-based support of our hypothesis, which states that under conditions of food abundance incompetent brain-pull will lead to build-ups in the supply chain culminating in obesity and type 2 diabetes. In the same way, we demonstrate support of the related hypothesis, which states that under conditions of food deprivation a competent brain-pull mechanism is indispensable for the continuance of the brain´s high energy level. In conclusion, we took the viewpoint of integrative physiology and provided evidence for the necessity of brain-pull mechanisms for the benefit of health. Along these lines, our work supports recent molecular findings from the field of neuroenergetics and continues the work on the “Selfish Brain” theory dealing with the maintenance of the cerebral and peripheral energy homeostasis.

  17. Influence of light-exposure methods and depths of cavity on the microhardness of dual-cured core build-up resin composites

    Directory of Open Access Journals (Sweden)

    Keiichi YOSHIDA

    2014-01-01

    Full Text Available Objective: The purpose of this study was to evaluate the Knoop hardness number (KHN of dual-cured core build-up resin composites (DCBRCs at 6 depths of cavity after 3 post-irradiation times by 4 light-exposure methods. Material and Methods: Five specimens each of DCBRCs (Clearfil DC Core Plus [DCP] and Unifil Core EM [UCE] were filled in acrylic resin blocks with a semi-cylindrical cavity and light-cured using an LED light unit (power density: 1,000 mW/cm2at the top surface by irradiation for 20 seconds (20 s, 40 seconds (40 s, bonding agent plus 20 seconds (B+20 s, or 40 seconds plus light irradiation of both sides of each acrylic resin block for 40 seconds each (120 s. KHN was measured at depths of 0.5, 2.0, 4.0, 6.0, 8.0, and 10.0 mm at 0.5 hours, 24 hours, and 7 days post-irradiation. Statistical analysis was performed using repeated measures ANOVA and Tukey's compromise post-hoc test with a significance level of p0.05. In DCP, and not UCE, at 24 hours and 7 days post-irradiation, the B+20 s method showed significantly higher KHN at all depths of cavity, except the depth of 0.5 mm (p<0.05. Conclusion: KHN depends on the light-exposure method, use of bonding agent, depth of cavity, post-irradiation time, and material brand. Based on the microhardness behavior, DCBRCs are preferably prepared by the effective exposure method, when used for a greater depth of cavity.

  18. Soil environmental conditions and microbial build-up mediate the effect of plant diversity on soil nitrifying and denitrifying enzyme activities in temperate grasslands.

    Directory of Open Access Journals (Sweden)

    Xavier Le Roux

    Full Text Available Random reductions in plant diversity can affect ecosystem functioning, but it is still unclear which components of plant diversity (species number - namely richness, presence of particular plant functional groups, or particular combinations of these and associated biotic and abiotic drivers explain the observed relationships, particularly for soil processes. We assembled grassland communities including 1 to 16 plant species with a factorial separation of the effects of richness and functional group composition to analyze how plant diversity components influence soil nitrifying and denitrifying enzyme activities (NEA and DEA, respectively, the abundance of nitrifiers (bacterial and archaeal amoA gene number and denitrifiers (nirK, nirS and nosZ gene number, and key soil environmental conditions. Plant diversity effects were largely due to differences in functional group composition between communities of identical richness (number of sown species, though richness also had an effect per se. NEA was positively related to the percentage of legumes in terms of sown species number, the additional effect of richness at any given legume percentage being negative. DEA was higher in plots with legumes, decreased with increasing percentage of grasses, and increased with richness. No correlation was observed between DEA and denitrifier abundance. NEA increased with the abundance of ammonia oxidizing bacteria. The effect of richness on NEA was entirely due to the build-up of nitrifying organisms, while legume effect was partly linked to modified ammonium availability and nitrifier abundance. Richness effect on DEA was entirely due to changes in soil moisture, while the effects of legumes and grasses were partly due to modified nitrate availability, which influenced the specific activity of denitrifiers. These results suggest that plant diversity-induced changes in microbial specific activity are important for facultative activities such as denitrification

  19. Appliance of AC Servo System in Build-up Force Standard Machine Based on FM354%基于FM354的交流伺服系统在机械比对力机上的应用

    Institute of Scientific and Technical Information of China (English)

    张大兴; 张振洲

    2012-01-01

    针对机械比对力机的工艺和控制要求,详细介绍了SIMODRIVE 611A交流伺服驱动系统在机械比对力机上的应用.利用高性能的伺服定位模块FM354,控制交流伺服驱动系统,满足机械比对力机对速度、力矩和大调速范围的要求,使力机满足国家称重传感器检定规程( JJG669 - 90)和称重传感器生产检测要求.%Aimed at technics and control requirement of build-up standard machine,this paper introduced the appliance of SI-MODRIVE 611A AC servo system in build-up standard machine. It use high-powered servo orientation module FM354 to control AC servo drive system. It satisfies the speed,moment and timing range of build-up standard machine,and also satisfies verification regulation of weighing cell (JJG669 -90) and measure requirement of weighing cell in manufacture.

  20. Galaxy stellar mass functions from ZFOURGE/CANDELS: An excess of low-mass galaxies since z = 2 and the rapid buildup of quiescent galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Tomczak, Adam R.; Tran, Kim-Vy H.; Papovich, Casey; Kawinwanichakij, Lalitwadee; Mehrtens, Nicola; Spitler, Lee R.; Tilvi, Vithal [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Quadri, Ryan F.; Kelson, Daniel D.; McCarthy, Patrick J.; Monson, Andrew J.; Persson, S. Eric [Carnegie Observatories, Pasadena, CA 91101 (United States); Labbé, Ivo; Straatman, Caroline M. S. [Sterrewacht Leiden, Leiden University, NL-2300 RA Leiden (Netherlands); Glazebrook, Karl; Allen, Rebecca; Kacprzak, Glenn G. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Brammer, Gabriel B. [European Southern Observatory, Alonso de Córdova 3107, Casilla 19001, Vitacura, Santiago (Chile); Van Dokkum, Pieter, E-mail: tomczak@physics.tamu.edu [Department of Astronomy, Yale University, New Haven, CT 06520 (United States)

    2014-03-10

    Using observations from the FourStar Galaxy Evolution Survey (ZFOURGE), we obtain the deepest measurements to date of the galaxy stellar mass function (SMF) at 0.2 < z < 3. ZFOURGE provides well-constrained photometric redshifts made possible through deep medium-bandwidth imaging at 1-2 μm. We combine this with Hubble Space Telescope imaging from the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey, allowing for the efficient selection of both blue and red galaxies down to stellar masses of ∼10{sup 9.5} M {sub ☉} at z ∼ 2.5. The total surveyed area is 316 arcmin{sup 2} distributed over three independent fields. We supplement these data with the wider and shallower NEWFIRM Medium-Band Survey to provide stronger constraints at high masses. Several studies at z ≤ 1.5 have revealed a steepening of the slope at the low-mass end of the SMF, leading to an upturn at masses <10{sup 10} M {sub ☉} that is not well described by a standard single-Schechter function. We find evidence that this feature extends to at least z ∼ 2 and that it can be found in both the star-forming and quiescent populations individually. The characteristic mass (M*) and slope at the lowest masses (α) of a double-Schechter function fit to the SMF stay roughly constant at Log(M/M {sub ☉}) ∼ 10.65 and ∼ – 1.5, respectively. The SMF of star-forming galaxies has evolved primarily in normalization, while the change in shape is relatively minor. Our data allow us, for the first time, to observe a rapid buildup at the low-mass end of the quiescent SMF. Since z = 2.5, the total stellar mass density of quiescent galaxies (down to 10{sup 9} M {sub ☉}) has increased by a factor of ∼12, whereas the mass density of star-forming galaxies only increases by a factor of ∼2.2.

  1. Effect of composite surface treatment and aging on the bond strength between a core build-up composite and a luting agent

    Directory of Open Access Journals (Sweden)

    Caroline COTES

    2015-02-01

    Full Text Available Objective The purpose of this study was to assess the influence of conditioning methods and thermocycling on the bond strength between composite core and resin cement. Material and Methods Eighty blocks (8×8×4 mm were prepared with core build-up composite. The cementation surface was roughened with 120-grit carbide paper and the blocks were thermocycled (5,000 cycles, between 5°C and 55°C, with a 30 s dwell time in each bath. A layer of temporary luting agent was applied. After 24 h, the layer was removed, and the blocks were divided into five groups, according to surface treatment: (NT No treatment (control; (SP Grinding with 120-grit carbide paper; (AC Etching with 37% phosphoric acid; (SC Sandblasting with 30 mm SiO2 particles, silane application; (AO Sandblasting with 50 mm Al2O3 particles, silane application. Two composite blocks were cemented to each other (n=8 and sectioned into sticks. Half of the specimens from each block were immediately tested for microtensile bond strength (µTBS, while the other half was subjected to storage for 6 months, thermocycling (12,000 cycles, between 5°C and 55°C, with a dwell time of 30 s in each bath and µTBS test in a mechanical testing machine. Bond strength data were analyzed by repeated measures two-way ANOVA and Tukey test (α=0.05. Results The µTBS was significantly affected by surface treatment (p=0.007 and thermocycling (p=0.000. Before aging, the SP group presented higher bond strength when compared to NT and AC groups, whereas all the other groups were statistically similar. After aging, all the groups were statistically similar. SP submitted to thermocycling showed lower bond strength than SP without thermocycling. Conclusion Core composites should be roughened with a diamond bur before the luting process. Thermocycling tends to reduce the bond strength between composite and resin cement.

  2. Heterogeneous Shallow-Shelf Carbonate Buildups in the Paradox Basin, Utah and Colorado: Targets for Increased Oil Production and Reserves Using Horizontal Drilling Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Thomas C. Chidsey; Kevin McClure; Craig D. Morgan

    2003-10-05

    The Paradox Basin of Utah, Colorado, Arizona, and New Mexico contains nearly 100 small oil fields producing from carbonate buildups within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to 10 wells with primary production ranging from 700,000 to 2,000,000 barrels (111,300-318,000 m{sup 3}) of oil per field and a 15 to 20 percent recovery rate. At least 200 million barrels (31.8 million m{sup 3}) of oil will not be recovered from these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Several fields in southeastern Utah and southwestern Colorado are being evaluated as candidates for horizontal drilling and enhanced oil recovery from existing vertical wells based upon geological characterization and reservoir modeling case studies. Geological characterization on a local scale is focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible reservoir compartmentalization, within these fields. This study utilizes representative cores, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells. The results of these studies can be applied to similar fields elsewhere in the Paradox Basin and the Rocky Mountain region, the Michigan and Illinois Basins, and the Midcontinent region. This report covers research activities for the first half of the fourth project year (April 6 through October 5, 2003). The work included (1) analysis of well-test data and oil production from Cherokee and Bug fields, San Juan County, Utah, and (2) diagenetic evaluation of stable isotopes from the upper Ismay and lower Desert Creek zones of the Paradox Formation in the Blanding sub-basin, Utah. Production ''sweet spots'' and potential horizontal drilling candidates were identified for Cherokee and Bug fields. In Cherokee field, the most productive wells are located in the

  3. The Young-Feynman two-slits experiment with single electrons: Build-up of the interference pattern and arrival-time distribution using a fast-readout pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Frabboni, Stefano [Department of Physics, University of Modena and Reggio Emilia, Via G. Campi 213/a, 41125 Modena (Italy); CNR-Institute of Nanoscience-S3, Via G. Campi 213/a, 41125 Modena (Italy); Gabrielli, Alessandro [Department of Physics, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy); INFN, Viale B. Pichat 6/2, 40127 Bologna (Italy); Carlo Gazzadi, Gian [CNR-Institute of Nanoscience-S3, Via G. Campi 213/a, 41125 Modena (Italy); Giorgi, Filippo [Department of Physics, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy); INFN, Viale B. Pichat 6/2, 40127 Bologna (Italy); Matteucci, Giorgio [Department of Physics, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy); Pozzi, Giulio, E-mail: giulio.pozzi@unibo.it [Department of Physics, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy); Cesari, Nicola Semprini; Villa, Mauro; Zoccoli, Antonio [Department of Physics, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy); INFN, Viale B. Pichat 6/2, 40127 Bologna (Italy)

    2012-05-15

    The two-slits experiment for single electrons has been carried out by inserting in a conventional transmission electron microscope a thick sample with two nano-slits fabricated by Focused Ion Beam technique and a fast recording system able to measure the electron arrival-time. The detector, designed for experiments in future colliders, is based on a custom CMOS chip equipped with a fast readout chain able to manage up to 10{sup 6} frames per second. In this way, high statistic samples of single electron events can be collected within a time interval short enough to measure the distribution of the electron arrival-times and to observe the build-up of the interference pattern. -- Highlights: Black-Right-Pointing-Pointer We present the first results obtained regarding the two-slits Young-Feynman experiment with single electrons. Black-Right-Pointing-Pointer We use two nano-slits fabricated by Focused Ion Beam technique. Black-Right-Pointing-Pointer We insert in the transmission electron microscope a detector, designed for experiments in future colliders. Black-Right-Pointing-Pointer We record the build-up of high statistic single electron interference patterns. Black-Right-Pointing-Pointer We measure the time distribution of electron arrivals.

  4. 高造斜率旋转地质导向技术在哈得逊油田的应用%Application of rotary geo-steering technology with high build-up rate in Hadson Oilifeld

    Institute of Scientific and Technical Information of China (English)

    王磊; 周波; 黎强; 苏小飞; 张连成; 滕鑫淼

    2015-01-01

    塔里木油田哈得逊薄油藏埋藏深、构造变化大,水平井钻井井眼轨迹控制困难,传统的旋转导向工具侧钻初期造斜率普遍不足,需使用弯螺杆马达增斜至30°左右后再更换工具,增加了钻井风险与周期。2013年,该区块应用高造斜率旋转导向工具(PowerDriver Archer RSS)及新一代地质导向技术(Scope系列),从侧钻点开始旋转导向钻进,在着陆及水平段加装地质导向工具,相比2012年,水平段平均井深增加214 m,钻井周期缩短36.7 d。在介绍高造斜率旋转导向以及随钻测井技术的基础上,结合现场应用实例分析,认为在哈得逊油藏,全井段旋转导向有利于降低井眼摩阻,节约钻进周期;地层探边及储层评价技术的应用提高了水平井的储层钻遇率,有利于该油藏的规模开采。%The Hadson thin reservoirs in Tarim Oilifeld has great burial depth and large structural variations. The wellbore trajectories in horizontal wells are hard to control. The traditional rotary steering tools could not realize enough build-up rate at the early stage of sidetracking, so the bent screw motor was used ifrst to build up hole angle to about 30°, then changed to other tools, which increased drilling risks and drilling cycle. In 2013, the rotary geo-steering tool with high build-up rate (PowerDriver Archer RSS) and a new generation of geo-steering technology (Scope series) were used in this Block, which started drilling with rotary steering from the sidetracking point, and geo-steering tools were added at landing and horizontal sections. Compared with 2012, the well depth in horizontal hole was increased by 214 m in average, and drilling cycle was less by 36.7 d. Based on rotary steering with high build-up rate and logging while drilling, and in conjunction with analysis of ifeld application cases, it was thought that full-hole rotary steering helps reduce hole friction in Hadson reservoir

  5. Model assumptions for computation of the energy build-up prior to a rock burst on the basis of extension measurements in the coal face. Modellvorstellungen zur Berechnung des Energiestaus vor einem Gebirgsschlag auf der Grundlage von Dehnungsmessungen im Kohlenstoss

    Energy Technology Data Exchange (ETDEWEB)

    Kotitschke, G.; Reisner, M. (DMT-Gesellschaft fuer Lehre und Bildung mbH, Essen (Germany))

    1991-08-01

    Place and time of a rock burst can be computed by means of extension measurements at the coal faces of a mined rock where a rock burst occurred upon approach of a coal face. The extension values measured from nine measuring points at the face side were evaluated. A mathematical model was developed; the model which computes the building-up energy potential which causes the rock burst. The results show that the latent energy potential increases continuously in the range of the rock burst. It increases exponentially in the last days, until a maximum is reached soon before the event. The process is different in the other areas, where the energy provided by the approaching is consumed in a more or less pronounced widening of the coal face. The energy build-up is low. Consequently, the danger potential can be calculated with the aid of a time and location-dependent 'sum extension function' from the extension behavior of the coal face. In this way, the hazard of a rock burst can be predicted. (orig./HS).

  6. The Star Formation Rate Function for Redshift z~4-7 Galaxies: Evidence for a Uniform Build-Up of Star-Forming Galaxies During the First 3 Gyr of Cosmic Time

    CERN Document Server

    Smit, R; Franx, M; Illingworth, G D; Labbé, I; Oesch, P A; van Dokkum, P G

    2012-01-01

    We combine recent estimates of dust extinction at z~4-7 with UV luminosity function (LF) determinations to derive star formation rate (SFR) functions at z~4, 5, 6 and 7. SFR functions provide a more physical description of galaxy build-up at high redshift and allow for direct comparisons to other techniques for determining the SFRs at lower redshifts. The present SFR functions are based on well-established z~4-7 UV LFs, UV-continuum slope trends with redshift and luminosity, and IRX-beta relations, and are well-described by Schechter relations. We extend the comparison baseline to z~2 by considering recent determinations of the H{\\alpha} and mid-IR luminosity functions. We find that the high-end turnover of the SFR function, log SFR*, increases linearly with cosmic time from ~5 M_sun/yr at z~8, 650 Myr after the Big Bang, to ~100 M_sun/yr at z~2, ~2.5 Gyr later. Recent results at z~10, close to the onset of galaxy formation, are consistent with this trend. These results provide strong evidence that galaxies b...

  7. 基于均力结构60 MN叠加式力值传递系统%The 60 MN Build-uP Force Delivery System Based on ComPensating Structure

    Institute of Scientific and Technical Information of China (English)

    池辉

    2015-01-01

    针对60 MN力标准机开展国际力值比对的需求,提出了一种带均力结构的叠加式力值传递系统。采用理论和数值模拟的方法分析了力值传递系统中的侧向力分布及均力结构对侧向力的影响,并通过实验进行了验证。结果表明,均力结构不但能减小传递到每个子传感器上的侧向力,而且能将侧向力较均匀地分配到各子传感器上,减小旋转效应对系统的影响。采用均力结构的力值传递系统能满足国际大力值比对与量值溯源的计量性能要求。%For needs of the force value comparison of 60 MN force standard machine,the 60 MN build-up system is studied. Through theoretical and numerical simulation,analysis on the lateral force distribution and the effect on the compensating structure to the lateral force is analysed,and the validation through the experiment and the international force value comparison is carried out. The results show that using compensating structure can not only reducing the lateral force which is passed on to each load sensor,but also can evenly distribute the lateral force to each load sensor,thus reducing the rotating effect. Reasonable compensating structure design can make the build—up system to have a stable mechanical properties,meet the requirements of both international great force value comparison and the domestic quantity traceability of measuring performance.

  8. 基于压力恢复曲线的油井堵水决策技术%Decision-making technique of oil well water plugging based on pressure buildup curve

    Institute of Scientific and Technical Information of China (English)

    曲占庆; 张杰; 齐宁; 曲永林; 王荣

    2013-01-01

    从渗流力学基础理论出发,利用压力恢复曲线,建立数学模型并推导出计算油井堵水的决策指数fPBD的公式,在此基础上,结合影响堵水油井选择的含水上升率指数和剩余油饱和度两个因素,运用综合模糊评判方法求取油井堵水综合决策值,对需堵水的油井进行选择.对垦东521区块某小块7口油井进行堵水选井决策.结果表明:fPBD与水相渗透率相关,可以作为堵水油井决策的依据;该决策选井方法考虑因素完善、数据易取、决策准确,与成功的经验选井方法得出结果吻合程度较高.%The mathematical model and decision-making index (fPBD) of water shutoff can be established using the seepage mechanics theory and pressure buildup curve.The target wells were selected based on the fPBD value,water cut rising index,remaining oil saturation and water shutoff comprehensive decision value obtained by fuzzy evaluation method.Seven production wells in KD521 block were chosen.The results show thatfPBD is related to water permeability,which can be considered as the foundation of water shutoff decision-making.The decision method of selecting well is characterized by taking into account all the factors,data easy to be obtained,and precise decision.The results agree well with that of experienced well selection method.

  9. P-T封隔器在异常高压低渗透层渗漏原因初探%Exploratory Research on the P-T Pack Leakage Reasons during Pressure Buildup Test in the Abmormal High Pressure Low Permeability Reservoir

    Institute of Scientific and Technical Information of China (English)

    白学东; 耿玉乾; 祁连秋

    2001-01-01

    The P-T pack leakage reasons are pointed out,which are accrued during pressure buildup test in the abnormal high pres sure low penneability reservoir. The calculation formation for determining the highest leakage pressures,and its practica bility is verified by the field examples. The leakage solving methods and measures are given.%用P-T封隔器测试高压低渗透层易发生渗漏,取不到完整的地层资料。经对P-T封隔器 进行井下受力分析,找出了封隔器发生渗漏的原因;给出了确定发生渗漏时最高关井压力的计算公 式并验证了其正确性;提出了解决P-T封隔器渗漏问题的相关措施。

  10. P-T封隔器在异常高压低渗透层渗漏原因初探%Exploratory Research on the P-T Pack Leakage Reasons during Pressure Buildup Test in the Abmormal High Pressure Low Permeability Reservoir

    Institute of Scientific and Technical Information of China (English)

    白学东; 耿玉乾; 祁连秋

    2001-01-01

    The P-T pack leakage reasons are pointed out,which are accruedduring pressure buildup test in the abnormal high pres sure low penneability reservoir. The calculation formation for determining the highest leakage pressures,and its practica bility is verified by the field examples. The leakage solving methods and measures are given.%用P-T封隔器测试高压低渗透层易发生渗漏,取不到完整的地层资料。经对P-T封隔器进行井下受力分析,找出了封隔器发生渗漏的原因;给出了确定发生渗漏时最高关井压力的计算公 式并验证了其正确性;提出了解决P-T封隔器渗漏问题的相关措施。

  11. Flare build-up study - Homologous flares group. I

    Science.gov (United States)

    Martres, M.-J.; Mein, N.; Mouradian, Z.; Rayrole, J.; Schmieder, B.; Simon, G.; Soru-Escaut, I.; Woodgate, B. E.

    1984-01-01

    Solar Maximum Mission observations have been used to study the origin and amount of energy, mechanism of storage and release, and conditions for the occurrence of solar flares, and some results of these studies as they pertain to homologous flares are briefly discussed. It was found that every set of flares produced 'rafales' of homologous flares, i.e., two, three, four, or more flares separated in time by an hour or less. No great changes in macroscopic photospheric patterns were observed during these flaring periods. A quantitative brightness parameter of the relation between homologous flares is defined. Scale changes detected in the dynamic spectrum of flare sites are in good agreement with a theoretical suggestion by Sturrock. Statistical results for different homologous flare active regions show the existence in homologous flaring areas of a 'pivot' of previous filaments interpreted as a signature of an anomaly in the solar rotation.

  12. Flare build-up study: Homologous flares group - Interim report

    Science.gov (United States)

    Woodgate, B. E.

    1982-01-01

    When homologous flares are broadly defined as having footpoint structures in common, it is found that a majority of flares fall into homologous sets. Filament eruptions and mass ejection in members of an homologous flare set show that maintainance of the magnetic structure is not a necessary condition for homology.

  13. Pilot studies on discolouration loose deposits' build-up

    NARCIS (Netherlands)

    Poças, Ana; Rebola, Nazaré; Rodrigues, Sérgio; Benoliel, Maria João; Rietveld, Luuk; Vreeburg, Jan; Menaia, José

    2015-01-01

    Tap water discolouration occurs due to resuspension of loose deposits (LD) that accumulate in drinking water distribution systems. Strategies for discolouration control involve network pipe cleaning and replacement of cast-iron pipes. However, the sole application of such measures is not generall

  14. Inductive Flux Build-Up of RMF Formed FRCs

    Science.gov (United States)

    Hoffman, Alan; Milroy, Richard

    2004-11-01

    Slow formation of high beta plasmas, such as FRCs, is difficult due to the need to build up plasma pressure rapidly enough to balance the dominant poloidal field pressure. Slow formation was attempted in the Coaxial Slow Source (CSS) device where 4-turn inner and outer coils were used to explore slower formation options, but it was not possible to operate at low enough densities to avoid radiative collapse.^1 FRCs have also been formed slowly at relatively low pressures and magnetic fields using Rotating Magnetic Fields (RMF), but it has also been difficult to overcome radiation barriers and achieve high temperatures due to relatively low power inputs.^2 We have performed calculations that show FRCs could be formed using RMF, and then augmented in flux and energy using the inductive input from a CSS type internal coil. With correct tailoring of the coil current profiles, the FRC could then be translated off the central coil. This methodology should be capable of producing hot, high flux FRCs using slow, low voltage technology. ^1 Z.A. Pietrzyk, et. al., Nuclear Fusion 27, 1478 (1987). ^2 H.Y. Guo, et. al., Phys. Plasmas 9, 185 (2002).

  15. Activity build-up in pressure vessel type reactors

    International Nuclear Information System (INIS)

    A simplified model is presented which permits the calculation of the average activity on the fuel elements of a reactor which operates under continuous refuelling, based on the assumption of crud interchange between fuel element surface and coolant in the form of particulate material only and using the crud specific activity as an empirical parameter determined experimentally. The net activity flux from core to out-of-core components is then calculated in the form of parametric curves depending upon crud specific activity and rate particulate release from fuel surface. The contribution to out-of-core radionuclide inventory arising in the release of activated material from core components is then assessed, and a way to estimate it numerically is presented. This method is based on experimentally determined cobalt-contents of structural materials and crud, and is specially suitable when high-cobalt alloys are present in-core. Activation of crud and release of activated materials are compared and it is shown that it is very likely that the latter may represent a sizable (and even the largest) fraction of the total cobalt activity. The use of the ratio of activities of 59 Fe to 54 Mn as a diagnostic tool for in-situ activation of structural materials is discussed. (author)

  16. CCIEE-SSI TO BUILDUP CHINA SHIPPING SOFT POWER

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2010-01-01

    @@ International shipping commonly uses indices, such as the index from the Baltic Shipping Exchange Kelaikesong. Most of the world's leading shipping agencies issue a Freight Index, which is based on tariffs as a fo-cal point, merely using the freight index as a measure of the state of devel-opment entails certain shortcomings, especially regarding the Forward Freight Agreement (FFA) which allows the introduction of additional freight indices and could become an object of financial speculation, which could not response to the actual situation of the global shipping industry.

  17. The Build-Up of Diversity in Complex Ecosystems

    CERN Document Server

    Tacchella, Andrea; Gabrielli, Andrea; Pietronero, Luciano

    2016-01-01

    Diversity is a fundamental feature of ecosystems, even when the concept of ecosystem is extended to sociology or economics. Diversity can be intended as the count of different items, animals, or, more generally, interactions. There are two classes of stylized facts that emerge when diversity is taken into account. The first are Diversity explosions: evolutionary radiations in biology, or the process of escaping 'Poverty Traps' in economics are two well known examples. The second is nestedness: entities with a very diverse set of interactions are the only ones that interact with more specialized ones. In a single sentence: specialists interact with generalists. Nestedness is observed in a variety of bipartite networks of interactions: Biogeographic, macroeconomic and mutualistic to name a few. This indicates that entities diversify following a pattern. Since they appear in such very different systems, these two stylized facts point out that the build up of diversity is driven by a fundamental probabilistic mec...

  18. Alternatives for contaminant control during MFTF plasma buildup

    International Nuclear Information System (INIS)

    The MFTF mirror device considers all low-energy species to be contaminants, since their primary effect is to erode the plasma boundary by charge-exchange reactions. Confinement for other than hydrogen isotypes is far from complete and confinement time is hardly more than transit time from the source to the end wall. The brevity of the confinement time makes it all the more necessary to prevent any contamination which might further reduce it. At Livermore, the historical solution to contaminant control has been to evaporate titanium onto cold surfaces. An alternative to this approach and its implications are considered

  19. Test for bacterial resistance build-up against plasma treatment

    International Nuclear Information System (INIS)

    It is well known that the evolution of resistance of microorganisms to a range of different antibiotics presents a major problem in the control of infectious diseases. Accordingly, new bactericidal ‘agents’ are in great demand. Using a cold atmospheric pressure (CAP) plasma dispenser operated with ambient air, a more than five orders of magnitude inactivation or reduction of Methicillin-resistant Staphylococcus aureus (MRSA; resistant against a large number of the tested antibiotics) was obtained in less than 10 s. This makes CAP the most promising candidate for combating nosocomial (hospital-induced) infections. To test for the occurrence and development of bacterial resistance against such plasmas, experiments with Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Enterococcus mundtii) were performed. The aim was to determine quantitative limits for primary (naturally) or secondary (acquired) resistance against the plasma treatment. Our results show that E. coli and E. mundtii possess no primary resistance against the plasma treatment. By generating four generations of bacteria for every strain, where the survivors of the plasma treatment were used for the production of the next generation, a lower limit to secondary resistance was obtained. Our results indicate that CAP technology could contribute to the control of infections in hospitals, in outpatient care and in disaster situations, providing a new, fast and efficient broad-band disinfection technology that is not constrained by bacterial resistance mechanisms. (paper)

  20. Model for radiation damage buildup in GaN

    International Nuclear Information System (INIS)

    We propose a model that explains both saturation and a shift of the maximum of bulk disorder profiles in ion-implanted GaN. Our model is based on two main assumptions that (i) the advancing amorphous/crystalline interface acts as a perfect sink for mobile point defects generated in the crystal bulk and (ii) the diffusion length of mobile defects increases with increasing ion fluence due to saturation of defect sinks in the bulk.

  1. DROWNING OF ATOLL-LIKE CARBONATE BUILDUPS ON THE NW PACIFIC GUYOTS LINKED TO CRETACEOUS EQUATORIAL CURRENTS%太平洋西北平顶海山上环礁型碳酸盐建造与白垩纪赤道洋流

    Institute of Scientific and Technical Information of China (English)

    Luba JANSA

    2005-01-01

    Cretaceous-Paleogene atolls. These formed through an accumulation of biogenic and inorganic carbonate sediments in mid-oceanic regions. Deep-sea drilling has documented that shallow-water carbonate buildups resembling atolls are capping many of the northwest Pacific guyots. In contrast to the coral-algal bulwarks of modern atolls, the perimeter ridges of these isolated Cretaceous and Paleogene atolls have negligible biohermal content and thus lower up-building capacity. These atolls drowned during the earliest Albian, latest Albian, late Maastrichtian and middle Eocene. The carbonate systems recovered from earlier brief episodes of subaerial exposure and subsequent transgressive flooding. However, when the northward drift of the Pacific plate carried piggy-back these guyots to within ~7° S paleolatitude, the atolls drowned. Several different hypotheses such as atolls emergence, karsting and subaerial erosion, enhanced equatorial upwelling, anoxia and/or presence of nutrient-rich, turbid waters were suggested as the causes of atoll drowning. Study of sedimentary sequences capping the guyots, comprised of a shallow water carbonate buildup, Fe-Mn crusts coating the top of the carbonate buildups and or volcanic pedestal surfaces, and of the overlying pelagic carbonate cap, provide evidence of an overwhelming effect of an equatorial current system on sediment deposition. These late Cretaceous-Paleogene in age atolls drowned when they came into the influence of the proto-South Equatorial Current (pSEC), which created an inhospitable environment for carbonate secreting organisms. A combination of continuing guyot subsidence and northwestward drift of the Pacific plate brought submerging surfaces of guyots into the influence of strong proto-Equatorial Undercurrent (50~400 m bsl), indicated by nondeposition and erosion on guyot surfaces. Precipitation of ferromanganese crusts was initiated between paleolatitude of ~5°S and the equator, when the tops of the guyots subsided

  2. Resistência à remoção por tração de coroas totais metálicas cimentadas em dentes com e sem reconstrução coronária Tensile strength of metal crowns cemented on dental and buildup surfaces

    Directory of Open Access Journals (Sweden)

    Eduardo Batista FRANCO

    1999-12-01

    C, 37°C and 55°C, and later subjected to tensile tests in a Universal Kratos testing machine. The results obtained were submitted to ANOVA, showing statistically significant differences (5% between the distinct conditions studied. Regarding the teeth without reconstruction, we verified improved results of Ketac-Cem when using polyacrylic acid. The teeth reconstructed with Vitremer did not show significant statistical difference between the two cementing agents. The reconstruction of teeth buildup surfaces did not hinder the retentiveness of the metal crowns.

  3. On-site evaluation of crud build-up and clad oxidation level

    International Nuclear Information System (INIS)

    The general trend in the late 1980's is to move toward longer operating cycles and extended burn-up. Among the questions raised by this increased performance PWR's waterside corrosion could be a potentially life-limiting problem. Therefore a large on site surveillance programme has been set up to collect data in various conditions: different plants and cycles, local burn-up up to 60 GWd/MTU, load follow operation, nucleate boiling... For that purpose FRAGEMA has developed a simple device, which can be easily installed in the spent fuel pit, featuring jointly a crud scrapping system and an Eddy-current probe for oxide thickness measurements: this makes possible correlation between clad corrosion and crud thickness. A telescopic pole is hanged along the wall of the pit, an X-Y carriage allows its movement in two perpendicular directions. At the bottom part either a scrapping head or an Eddy-current probe can be mounted. Both selection of the areas to be examined and monitoring during scrapping and measurements are made with the help of a T.V. camera. Design of the tool has been focused on safety aspect to avoid any deterioration of the fuel assembly and to minimize radiation exposure during crud collection and filtration. The positioning and the touching of the eddy-current probe on the rod have been carefully studied to ensure reliable data collection. For calibration, oxidized zircaloy tubes with well known oxide thickness, are used. Detailed description of the complete device and experience obtained through several campaigns are presented in this paper. (author)

  4. Primary water chemistry monitoring from the point of view of radiation build-up

    International Nuclear Information System (INIS)

    Basic operational principles of a computer code system calculating the primary circuit corrosion product activities based on actual measured plant chemistry data are presented. The code system consists of two parts: FeSolub.prg: calculates the characteristic iron solubilities based on actual primary water chemistry (H3BO3KOH, ... etc.) and plant load (MW) data. A developed solubility calculation method has been applied fitted to magnetite solubility data of several authors; RADTRAN.exe: calculates primary circuit water and surface corrosion product activities based on results of FeSolub.prg or planned water chemistry data up to the next shutdown. The computer code system is going to be integrated into a general primary water chemistry monitoring and surveillance system. (author). 15 refs, 4 figs, 3 tabs

  5. Interface slip and the buildup of hydrodynamic pressure in nanoscale bearings

    International Nuclear Information System (INIS)

    A new type of hydrodynamic bearing is presented. Instead of physically forming a wedged space by two plates, the bearing consists of two parallel plates, with regions of different wettability on one of the surfaces. With the introduction of such a wettability-patterned surface, the hydrodynamic pressure can be built up because the local slip length over different regions in the bearing is different and results in similar velocity profiles to that in a traditional wedged bearing. Molecular dynamics simulation results indicate that the hydrodynamic pressure is proportional to the shear velocity. However, as the shear velocity exceeds a critical value, the slip length becomes infinite and the hydrodynamic bearing loses its function

  6. Energy Buildup, Flux Confinement and Helicity Accumulation in the Solar Corona

    Institute of Scientific and Technical Information of China (English)

    You-Qiu Hu; Wen Li

    2006-01-01

    Starting from a dipole field and a given distribution of footpoint displacement of field lines on the photosphere, we find axisymmetric, force-free field solutions in spherical coordinates that have the same distribution of normal field on the photosphere and magnetic topology as the dipole field. A photospheric shear is introduced in the azimuthal direction in a region that strides across the equator and ends at latitude λs. The footpoint displacement has a sine distribution in latitude and a peak amplitude of ψm. The magnetic energy E, azimuthal flux Fψ, and magnetic helicity HT in the solar corona are then calculated for each force-free field solution. It is found that for a given shear region range λs, all of the three quantities increase monotonically with increasing ψm. In particular, both Fψ and HT have a linear dependence on ψm. When ψm reaches a certain critical value ψmc, the force-free field loses equilibrium, leading to a partial opening of the field and the appearance of a current sheet in the equatorial plane. At this point, E, Fψ and HT reach their maximum values,Ec, Fψc and HTc. Ec increases, and Fψc and HTc decrease with decreasing λs. It is found that Ec is always smaller than the open field energy, in agreement with the Aly conjecture. Of the three critical parameters, Ec has the weakest dependence on λs. Therefore, if one is interested in the transition of a magnetic configuration from a stable state to a dynamic one, the magnetic energy is probably the most appropriate marker of the transition.

  7. Magnetohydrodynamic and thermal processes in solar flare energy build-up and release

    International Nuclear Information System (INIS)

    A solar flare can be described as an instability in the upper solar atmosphere that converts 1028 ergs to 1032 ergs of magnetic energy into other forms of energy, mainly kinetic energy. The solar flare gives rise to a wealth of observable phenomena. The author develops a fairly simple model to explain many of these apparently very diverse features of solar flares. (Auth.)

  8. The challenging SO2-mediated chemical build-up of protein aggregates in wines.

    Science.gov (United States)

    Chagas, Ricardo; Ferreira, Luísa M; Laia, César A T; Monteiro, Sara; Ferreira, Ricardo B

    2016-02-01

    Despite the extensive research performed during the last decades, the multifactorial mechanism responsible for white wine protein haze formation is not fully characterized. A model is proposed, which is essentially based on two postulates: the experimental identification of sulfur dioxide as the non-proteinaceous factor, and the inference from reliable data available in the literature of the dynamic chemistry played by wine protein sulfhydryl groups. Unlike other reducing agents, addition of SO2 to must/wine upon heating cleaves intraprotein disulfide bonds, hinders thiol-disulfide exchange during protein interactions, and leads to formation of novel interprotein disulfide bonds. These bonds are ultimately responsible for wine protein aggregation following a nucleation-growth kinetic model, as shown by Dynamic Light Scattering experiments. The model was tested in wine model solution (using total and fractionated wine proteins) and validated under real wine conditions. The results achieved may open the way to develop techniques that will find wide application in the wine industry.

  9. Bar-Driven Mass Build-Up within the Central 50pc of NGC6946

    CERN Document Server

    Schinnerer, E; Emsellem, E; Downes, D

    2007-01-01

    We have used the new extended A configuration of the IRAM Plateau de Bure interferometer to study the dense molecular gas in the nucleus of the nearby spiral galaxy NGC6946 at unprecedented spatial resolution in the HCN(1-0) and CO(2-1) lines. The gas distribution in the central 50pc has been resolved and is consistent with a gas ring or spiral driven by the inner 400pc long stellar bar. For the first time, it is possible to directly compare the location of (dense) giant molecular clouds with that of (optically) visible HII regions in space-based images. We use the 3mm continuum and the HCN emission to estimate in the central 50pc the star formation rates in young clusters that are still embedded in their parent clouds and hence are missed in optical and near-IR surveys of star formation. The amount of embedded star formation is about 1.6 times as high as that measured from HII regions alone, and appears roughly evenly split between ongoing dust-obscured star formation and very young giant molecular cloud cor...

  10. Optimal Pile Arrangement for Minimizing Excess Pore Water Pressure Build-Up

    DEFF Research Database (Denmark)

    Barari, Amin; Saadati, Meysam; Ibsen, Lars Bo;

    2013-01-01

    Numerical analysis of pile group in a liquefiable soil was considered to investigate the influence of pile spacing on excess pore pressure distribution and liquefaction potential. The analysis is conducted using a two-dimensional plain strain finite difference program considering a nonlinear...

  11. Status of Electron-Cloud Build-Up Simulations for the Main Injector

    International Nuclear Information System (INIS)

    We provide a brief status report on measurements and simulations of the electron cloud in the Fermilab Main Injector (MI). Areas of agreement and disagreement are spelled out, along with their possible significance. An upgrade to the MI is being considered that would increase the bunch intensity Nb, from the present ∼ 1 x 1011 to 3 x 1011, corresponding to a total pulse intensity Ntot = 16.4 x 1013, in order to generate intense beams for the neutrino program. Such an increase in beam intensity would place the MI in a parameter regime where other storage rings have seen a significant EC effect. Motivated by this concern, efforts have been undertaken over the recent past to measure and simulate the magnitude of the effect and to assess its operational implications on the proposed upgrade. We report here a summary of simulation results obtained with the code POSINST, and certain benchmarks against measurements. Unless stated otherwise, the simulation parameters used are shown in Tab. 1. Some of these represent a slightly simplified version of the MI operation.

  12. Modelling of e-cloud build-up in grooved vacuum chambers using POSINST

    International Nuclear Information System (INIS)

    Use of grooved vacuum chambers have been suggested as a way to limit electron cloud accumulation in the ILC-DR. We report on simulations carried out using an augmented version of POSINST, accounting for e-cloud dynamics in the presence of grooves, and make contact with previous estimates of an effective secondary electron yield for grooved surfaces

  13. Buildup of electron cloud with different bunch pattern in the presence of solenoid field

    International Nuclear Information System (INIS)

    We have augmented the code POSINST to include solenoid fields, and used it to simulate the build up of electron cloud due to electron multipacting in the PEP-II positron ring. We find that the distribution of electrons is strongly affected by the resonances associated with the cyclotron period and bunch spacing. In addition, we discover a threshold beyond which the electron density grows exponentially until it reaches the space charge limit. The threshold does not depend on the bunch spacing but does depend on the positron bunch population

  14. Status of Electron-Cloud Build-Up Simulations for the Main Injector

    OpenAIRE

    Furman, M.A.

    2011-01-01

    We provide a brief status report on measurements and simulations of the electron cloud in the Fermilab Main Injector. Areas of agreement and disagreement are spelled out, along with their possible significance.

  15. Modelling of e-cloud build-up in grooved vacuum chambers using POSINST

    OpenAIRE

    Venturini, Marco; Celata, C.; Furman, Miguel; Vay, Jean-Luc; Pivi, Mauro

    2008-01-01

    Use of grooved vacuum chambers have been suggested as a way to limit electron cloud accumulation in the ILC-DR. We report on simulations carried out using an augmented version of POSINST, accounting for e-cloud dynamics in the presence of grooves, and make contact with previous estimates of an effective secondary electron yield for grooved surfaces.

  16. Log jams and flood sediment buildup caused channel avulsion in the Pennsylvanian of Atlantic Canada

    DEFF Research Database (Denmark)

    Gibling, Martin R; Bashforth, Arden Roy; Falcon-Lang, Howard J;

    2010-01-01

    Accumulations of logs and flood sediment frequently block modern channels and may trigger avulsion, but these effects are difficult to demonstrate for the ancient record. Braided-fluvial channels in the Pennsylvanian South Bar Formation of Atlantic Canada contain sandstone successions up to 6 m...... thick of sigmoidal cross-beds, plane beds, and antidunes, deposited rapidly at highflow-stage. These strata are commonly capped by accumulations up to 2.5 m thick of flattened, coalified logs and coal intraclasts (originally peat fragments), many of which are overlain by mudstone laid down in abandoned...... channels. The logs include lycopsids, calamiteans, tree ferns, pteridosperms and cordaitaleans, inferred to have grown on inactive braided tracts near the channels. A compaction estimate suggests that one log accumulation was originally more than four times its present thickness. Most accumulations...

  17. Modelling Venting and Pressure Build-up in a 18650 LCO Cell during Thermal Runaway (ABSTRACT)

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Veje, Christian; White, Ralph;

    may lead to fires and explosions. To prevent this, it is therefore important to model thermal runaway considering different events such as venting and the pressure development inside the battery cell, which makes the main purpose of this paper. A model consisting of the different decomposition...... reactions in the anode, cathode and SEI, but also in electrochemical reactions and boiling of the electrolyte is developed for a cylindrical 18650 LCO cell (Lithium Cobalt Oxide). For determining the pressure and the temperature after venting, the isentropic flow equations are included in the model....... By fitting the activation energies, and measuring experimentally the mass of the ejecta during thermal runaway, the model is compared and validated against an extensive experiment performed by Golukbov et al. [1] during oven heating. When analysing the results, it is found that by including the venting...

  18. [Structure and ecological benefits of urban forest in Shenyang build-up area].

    Science.gov (United States)

    Hu, Zhibin; He, Xingyuan; Chen, Wei; Li, Yuehui; Li, Haimei

    2003-12-01

    Investigations were made in the sampling plots covering 243 km2 of the Shenyang urban area, and the results were used as the input for the Urban Forest Management Information System (UFMIS), which was developed based on the model of CITY green. With this system, and using tree species, tree density, tree height grade distribution, tree DBH (diameter at beast height) grade distribution, and tree health condition as parameters, the land use and forest structure in Shenyang City were analyzed. It was found that there were 1,914,500 trees in Shenyang, belonging to 136 species. The 25 dominant species accounted for 84.78% of the total number of trees, and the forest coverage was 9.765%. Trees with DBH 0.5 m accounted for 82.8% of the total, and the young, middle-aged and old trees occupied 27%, 58% and 15% of the total, respectively. The healthy status of 84% of the trees was above middle level. Therefore, the forest in Shenyang urban is at a stable stage. According to the statistical results from UFMIS, the ecological value of forest in Shenyang urban is as high as 26,526,955. 1 USD in terms of economy. PMID:15031897

  19. The Hierarchical Build-Up of Massive Galaxies And the Intracluster Light Since z=1

    Energy Technology Data Exchange (ETDEWEB)

    Conroy, Charlie; /Princeton U.; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC; Kravtsov, Andrey V.; /Chicago U., Astron. Astrophys. Ctr. /Chicago U., EFI

    2007-03-19

    We use a set of simulation-based models for the dissipationless evolution of galaxies since z = 1 to constrain the fate of accreted satellites embedded in dark matter subhalos. These models assign stellar mass to dark matter halos at z = 1 by relating the observed galaxy stellar mass function (GSMF) to the halo+subhalo mass function monotonically. The evolution of the stellar mass content is then followed using halo merger trees extracted from N-body simulations. Our models are differentiated only in the fate assigned to satellite galaxies once subhalos, within which satellites are embedded, disrupt. These models are confronted with the observed evolution in the massive end of the GSMF, the z {approx} 0 brightest cluster galaxy (BCG)-cluster mass relation, and the combined BCG and intracluster light (ICL) luminosity distribution--all observables expected to evolve approximately dissipationlessly since z = 1. The combined observational constraints favor a model in which the vast majority ({approx}> 80%) of satellite stars from disrupted subhalos go into the ICL (operationally defined here as light below a surface brightness cut of {mu}{sub i} {approx} 23mag arcsec{sup -2}). Conversely, models that leave behind a significant population of satellite galaxies once the subhalo has disrupted are strongly disfavored, as are models that put a significant fraction of satellite stars into the BCG. Our results show that observations of the ICL provide useful and unique constraints on models of galaxy merging and the dissipationless evolution of galaxies in groups and clusters.

  20. Effect of density of hydrogen-bonding donor on hydrogen-bonded multilayer buildup

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hongyu; MA Ning; WANG Zhiqiang

    2005-01-01

    The effect of density of hydrogen-bonding donor (HBD) on the formation of layer-by-layer assemblies of poly(4-vinylpyridine) and poly(4-vinylphenol) was investigated. For this purpose, a series of ethyl-substituted poly(4-vinylphenol) (EsPVPhf) with variable ethyl substitute percentage was synthesized by grafting the phenol moiety along the poly(4-vinylphenol) backbone with 1-bromoethane. UV-vis spectroscopy revealed a uniform deposition process of the hydrogen-bonded multilayer consisting of poly(4- vinylpyridine) (PVPy) and EsPVPhf with variable density of HBD. Notably, it was found that increasing the HBD density of EsPVPhf resulted in a marked decrease of both amount of polymers adsorbed and film thickness, which should be related to the EsPVPhf conformation change from coiled state to extended conformation in ethanol solution. Compared with the effect of charge density in polyelectrolyte multilayer, however, there does not exist a critical density of HBD in our case of hydrogen-bonded multilayer assembly. In addition, surface structures of PVPy/EsPVPhf multilayer films also can be tailored controllably by adjusting HBD density of EsPVPhf. As a result, a new method for tuning the structure of hydrogen-bonding-directed multilayer films was developed.

  1. Effect of the LHC Beam Screen Baffle on the Electron Cloud Buildup

    CERN Document Server

    Romano, Annalisa; Li, Kevin; Rumolo, Giovanni

    2016-01-01

    Electron Cloud (EC) has been identified as one of the major intensity-limiting factors in the CERN Large Hadron Collider (LHC). Due to the EC, an additional heat load is deposited on the perforated LHC beam screen, for which only a small cooling capacity is available. In order to preserve the superconducting state of the magnets, pumping slots shields were added on the outer side of the beam screens. In the framework of the design of the beam screens of the new HL-LHC triplets, the impact of these shields on the multipacting process was studied with macroparticle simulations. For this purpose multiple new features had to be introduced in the PyECLOUD code. This contribution will describe the implemented simulation model and summarize the outcome of this study.

  2. Buildup of multilayer structures of organic-inorganic hybrid ultra thin films by wet process

    International Nuclear Information System (INIS)

    Multilayer structures of alternate organic and inorganic semiconductors were fabricated by the wet processes that control thickness of each layer with nanometre level. Organic layers were deposited as electron-donor including poly(p-phenylene vinylene) by the layer-by-layer adsorption method. Inorganic layers composed of titanium oxide were fabricated as electron-acceptor by the surface sol-gel process. Clearly, periodic and uniform nanostructures were confirmed by glow discharge optical emission spectroscopy and transmission electron microscopy analyses. The multilayer exhibited a photovoltaic effect under illumination. The fabrication of those structures by wet process under room temperature and normal pressure will be one of the important methods in energy-saving nano-technology

  3. Understanding the build-up of a technological innovation system around hydrogen and fuel cell technologies

    NARCIS (Netherlands)

    Suurs, R.A.A.; Hekkert, M.P.; Smits, R.E.H.M.

    2009-01-01

    This study provides insight into the development of hydrogen and fuel cell technologies in the Netherlands (1980-2007). This is done by applying a Technological Innovation System (TIS) approach. This approach takes the perspective that a technology is shaped by a surrounding network of actors, insti

  4. Modeling of air-droplet interaction, substrate melting and coating buildup in thermal spraying

    Science.gov (United States)

    Wei, Guanghua

    Among the many surface coating techniques now available, thermal spray is known to offer the most advantages. It can meet a wide range of technical and engineering requirements in a relatively inexpensive and easily controllable way with the capability of producing repeatable results. In the last few decades a lot of important strides have been made in the field of measurements and modelling of thermal spraying. However, due to the complex of the process and the lack of basic materials-based knowledge about the particle melting, spreading and deposition, the relationship between the process parameters and the coating properties still remains unclear. In thermal spraying, a particle is melted to form a droplet with morphology and thermal- and kinetic-energy status change by the interaction with the plasma/flame. In order to produce higher-quality coatings and expand the use of this versatile family of technologies, modelling of the particle behaviors during in-flight, spreading and deposition is essential. This thesis investigates the connections between particle characteristics and coating properties. Momentum, heat and mass transfer phenomena related to particle in-flight, droplet impacting, spreading, and splat layering are studied. Numerical models are developed to establish the quantitative relationships between spray parameters, particle and substrate properties and deposition characteristics. Most existing theoretical studies of in-flight particle assume that the particle is in a spherical shape without voids inside. The behavior of porous particles in thermal spray has not been well understood. However, the presence of voids in the feedstock powders may have a great impact on particle in-flight behaviors such as particle acceleration, melting and oxidation because a hollowed particle is also lighter than a densed one and this will affect the particle trajectory. The particle shape also needs to be taken into account because it influences the drag force and particle feeding velocity. In this thesis, the level set method is used to study the interaction between the droplet and the surrounding air. The level set function is used to track the deformation of the free surface. The capability of this model on accurately and efficiently simulating the droplet deformation and oscillation is demonstrated. The droplet deformation during in-flight caused by the air-droplet interaction and the droplet-substrate interaction are considered here. Particles with different surface tension and morphologies are studied as well. Droplet substrate interaction is studied to understand the substrate melting behavior. A numerical model is developed to investigate the droplet solidification, substrate melting and re-solidification. A dimensionless parameter, "temperature factor", is proposed from analysis and it can be used as an indicator to predict whether substrate melting will occur for a certain combination of the droplet and substrate. This parameter can be correlated with the maximum melting depth of the substrate. The possibility of heating up the substrate by plasma flame, and attaching a temperature-control device on the backside of the substrate to achieve substrate melting is studied. The substrate front surface temperature can be controlled at a sufficient high temperature. With additional heating from superheated molten droplets and the latent heat of droplet solidification, a thin liquid layer of the substrate can be obtained and epitaxy growth of the splats is possible. This could expand thermal spray technology to the applications of semiconductor and solar energy, both of which need epitaxy crystal with big sizes. To better control the existing thermal spray process, it is important to develop the quantitative relationships between spray parameters and coating characteristics. Until recently, the simulation studies have been focused on two-dimensional models and prediction of the cross-section structure of deposited layers; although a few three-dimensional models are developed as well by using the statistical particle par

  5. The VIMOS VLT Deep Survey: The build-up of the colour-density relation

    CERN Document Server

    Cucciati, O; Marinoni, C; Ilbert, O; Bardelli, S; Franzetti, P; Lefèvre, O; Pollo, A; Zamorani, G; Cappi, A; Guzzo, L; McCracken, H J; Meneux, B; Scaramella, R; Scodeggio, M; Tresse, L; Zucca, E; Bottini, D; Garilli, B; Le Brun, V; MacCagni, D; Picat, J P; Vettolani, G; Zanichelli, A; Adami, C; Arnaboldi, M; Arnouts, S; Bolzonella, M; Charlot, S; Ciliegi, P; Contini, T; Foucaud, S; Gavignaud, I; Marano, B; Mazure, A; Merighi, R; Paltani, S; Pellò, R; Pozzetti, L; Radovich, M; Bondi, M; Bongiorno, A; Busarello, G; De la Torre, S D; Gregorini, L; Lamareille, F; Mathez, G; Mellier, Y; Merluzzi, P; Ripepi, V; Rizzo, D; Temporin, G; Vergani, D

    2006-01-01

    We investigate the redshift and luminosity evolution of the galaxy colour-density relation using the data from the First Epoch VIMOS-VLT Deep Survey (VVDS). The size (6582 galaxies), depth (I_AB<=24) and redshift sampling rate of the survey enable us to reconstruct the 3D galaxy environment on relatively local scales (R=5 Mpc) up to z~1.5. Particular attention has been devoted to calibrate a density reconstruction scheme, which factors out survey selection effects and reproduces in an unbiased way the underlying 'real' galaxy environment. While at lower redshift we confirm the existence of a steep colour-density relation, with the fraction of the reddest(/bluest) galaxies of the same luminosity increasing(/decreasing) as a function of density, this trend progressively disappears and eventually reverses in the highest redshift bins investigated. The rest frame U-V colour-magnitude diagram shows a bimodal pattern in both low and high density environments up to z ~ 1.5. The bimodal distribution is not univers...

  6. Witnessing the build-up of the colour-density relation

    CERN Document Server

    Cucciati, O; Marinoni, C; Ilbert, O; Bardelli, S; Franzetti, P; Lefèvre, O; Pollo, A; Zamorani, G; Cappi, A; Guzzo, L; McCracken, H J; Meneux, B; Scaramella, R; Scodeggio, M; Tresse, L; Zucca, E; Bottini, D; Garilli, B; Le Brun, V; MacCagni, D; Picat, J P; Vettolani, G; Zanichelli, A; Adami, C; Arnaboldi, M; Arnouts, S; Bolzonella, M; Charlot, S; Ciliegi, P; Contini, T; Foucaud, S; Gavignaud, I; Marano, B; Mazure, A; Merighi, R; Paltani, S; Pellò, R; Pozzetti, L; Radovich, M; Bondi, M; Bongiorno, A; Busarello, G; De la Torre, S; Gregorini, L; Lamareille, F; Mathez, G; Mellier, Y; Merluzzi, P; Ripepi, V; Rizzo, D; Temporin, G; Vergani, D

    2006-01-01

    We investigate the redshift and luminosity evolution of the galaxy colour-density relation using the data from the First Epoch VIMOS-VLT Deep Survey (VVDS) on scales of R=5 h^(-1)Mpc up to redshift z ~ 1.5. While at lower redshift we confirm the existence of a steep colour-density relation, with the fraction of the reddest(/bluest) galaxies of the same luminosity increasing(/decreasing) as a function of density, this trend progressively disappears in the highest redshift bins investigated.Our results suggest the existence of an epoch (more remote for brighter galaxies) characterized by the absence of the colour-density relation on the R=5 h^(-1)Mpc scales investigated. The rest frame u*-g' colour-magnitude diagram shows a bimodal pattern in both low and high density environments up to redshift z ~ 1.5. We find that the bimodal distribution is not universal but strongly depends upon environment. Both the colour-density and colour-magnitude-density relations, on the R=5 h^(-1)Mpc scales, appear to be a transien...

  7. Internal filtration and external filter cake build-up in sandstones

    NARCIS (Netherlands)

    Al-Abduwani, F.A.H.

    2005-01-01

    Water injection is an integral constituent of most field development scenarios. This injection may take place for secondary recovery and pressure maintenance such as sea water injection. Alternatively, it may take place as a waste water disposal method as in the case of produced water re-injection.

  8. Studies of organic matter turnover and nutrient buildup in a Bangladesh soil for sustainable agriculture

    International Nuclear Information System (INIS)

    A field experiment was conducted with a wheat-rice cropping system over four consecutive years, 1996 to 2000. The objective was to assess whether an adapted residue-management system would enhance the potential to retain added nutrients within the crop-soil system with concomitant increases in yields. To synchronize nutrient release from organic amendments with nutrient uptake by the crop, another experiment was conducted in 1997/98. The rate of decomposition and the release of N from crop residues were determined in an incubation study conducted under field conditions in small 15N microplots contained within cylinders. Results indicated that wheat residue was enriched in 15N at 4.3 to 5.5% a.e., where 10.5% 15N a.e. labelled ammonium sulphate had been applied. Total yields of rice (grain + straw) increased significantly in treatment T2 where 15N-labelled crop residue was applied at 5 Mg ha-1, i.e. 14.0, 11.6, 12.6 and 12.6 Mg ha-1 in the first, second, third and fours years, respectively. The 15N-labelled wheat residue contributed about 3 kg N ha-1 to the total N pool of the first crop of rice in treatment T2 and 0.99, 0.39 and 0.15 N kg ha-1 in the second, third, and fourth years respectively. The 15N fertilizer, which was applied to the first crop (wheat), was gradually recovered in the subsequent crops in plots where 15 N-labelled crop residues were incorporated, and more 15N was retained in the soil than was taken up by plants. In the incubation study, N release from crop residues showed an irregular relationship with crop-N uptake. Changes were observed in soil mineral N following addition of crop residues. The greatest release of 15N from residues was recorded with the longest incubation period. (author)

  9. Build-up and decay of fuel actinides in the fuel cycle of nuclear reactors

    International Nuclear Information System (INIS)

    For boiling water reactors, pressurized light-water reactors, pressure-tube-type heavy water reactors, high-temperature gas-cooled reactors, and sodium-cooled fast breeder reactors, uranium fueled and mixed-oxide fueled, each of 1000 MWe, the following have been studied: (1) quantities of plutonium and other fuel actinides built up in the reactor, (2) cooling behaviors of activities of plutonium and other fuel actinides in the spent fuels, and (3) activities of plutonium and other fuel actinides in the high-level reprocessing wastes as a function of storage time. The neutron cross section and decay data of respective actinide nuclides are presented, with their evaluations. For effective utilization of the uranium resources and easy reprocessing and high-level waste management, a thermal reactor must be fueled with uranium; the plutonium produced in a thermal reactor should be used in a fast reactor; and the plutonium produced in the blanket of a fast reactor is more appropriate for a fast reactor than that from a thermal reactor. (auth.)

  10. Testing Cold Dark Matter with the hierarchical buildup of stellar light

    CERN Document Server

    Balogh, Michael L; Bower, Richard G; Eke, Vincent R

    2008-01-01

    (Abridged) We demonstrate that the tenet of hierarchical structure growth leads directly to a robust, falsifiable prediction for the correlation between stellar fraction (fstar) and total system mass (M500) of galaxy groups and clusters. This prediction is relatively insensitive to the details of baryonic physics or cosmological parameters. In particular, if the fstar-M500 relation is fixed and does not evolve with redshift, CDM models predict the logarithmic slope of this relation to be b>-0.3. This constraint can be weakened if the fstar-M500 relation evolves strongly, but this implies more stars must be formed in situ in groups at low redshift. Conservatively requiring that at least half the stars in groups were formed by z=1, the constraint from evolution models is b>-0.35. Since the most massive clusters (M500=1E15 Msun) are observed to have fstar=0.01, this means that groups with M500=5E13 Msun must have fstar0.04 in groups, leading to b=-0.64. If confirmed, this would rule out hierarchical structure fo...

  11. Quantifying the buildup in extent and complexity of free exploration in mice

    OpenAIRE

    Benjamini, Yoav; Fonio, Ehud; Galili, Tal; Havkin, Gregor Z.; Golani, Ilan

    2011-01-01

    To obtain a perspective on an animal's own functional world, we study its behavior in situations that allow the animal to regulate the growth rate of its behavior and provide us with the opportunity to quantify its moment-by-moment developmental dynamics. Thus, we are able to show that mouse exploratory behavior consists of sequences of repeated motion: iterative processes that increase in extent and complexity, whose presumed function is a systematic active management of input acquired durin...

  12. Buildup of CO2 in Lake Nyos and evaluation of recurrence of future gas outbursts

    International Nuclear Information System (INIS)

    On 21 August 1986 an outburst of lethal gas came from Lake Nyos, Cameroon, killed about 1700 people. The gas was found to be CO2 dissolved in the lake; it was suddenly released from the lake to the atmosphere and flowed rapidly down valleys asphyxiating people and animals in its path. Isotopic analyses of carbon (δ13C = -3/4 per mille) and helium (3He/4He 5.7 Ratm) of the dissolved gases indicate that CO2 and He are of mantle origin. The conductivity-temperature-depth profile measurements and chemical analyses of the lake water done during November 1986 and December 1988 revealed that the temperature, total dissolved solid and CO2 content of the water increased markedly from 160 m to the bottom. This result supports the view that CO2 is being supplied to the lake bottom in the form of warm, CO2-charged, mineralized water favoring the ''limnological'' hypothesis rather than the ''volcanic'' one for the cause of the gas bursts in 1986. The heat and CO2 fluxes at the bottom were estimated to be 0.43 MW and 1.0 Gmol/y, respectively. The CO2 flux is large enough to saturate the lake's hypolimnion within about 30 years. Considering that the gas release may not require full saturation of the lake, another gas outburst could occur at any time. Regular geochemical and limnological monitoring of the lake is highly desirable in order to prevent future disasters. Remedial measures to remove CO2 from the bottom water should also be taken. (author). 25 refs, 10 figs, 1 tab

  13. Adaptive build-up and breakdown of trust : An agent based computational approach

    NARCIS (Netherlands)

    Gorobets, A.; Nooteboom, B.

    2005-01-01

    This article employs Agent-Based Computational Economics (ACE) to investigate whether, and under what conditions, trust is viable in markets. The emergence and breakdown of trust is modeled in a context of multiple buyers and suppliers. Agents develop trust in a partner as a function of observed loy

  14. SOIL-AIR PERMEABILITY MEASUREMENT WITH A TRANSIENT PRESSURE BUILDUP METHOD

    Science.gov (United States)

    An analytical solution for transient pressure change in a single venting well was derived from mass conservation of air, Darcy's law of flow in porous media, and the ideal gas law equation of state. Slopes of plots of Pw2 against ln (t+Δt)/Δt similar to Homer's plot were used to ...

  15. A new buildup biofilm model that mimics accumulation of material in flexible endoscope channels.

    Science.gov (United States)

    da Costa Luciano, Cristiana; Olson, Nancy; DeGagne, Patricia; Franca, Rodrigo; Tipple, Anaclara Ferreira Veiga; Alfa, Michelle

    2016-08-01

    The objective of this study was to develop a new build up biofilm (BBF) model that was based on repeated exposure to test soil containing Enterococcus faecalis and Pseudomonas aeruginosa and repeated rounds of fixation to mimic the accumulation of patient material in endoscope channels during reprocessing. The new BBF model is a novel adaptation of the minimum biofilm effective concentration (MBEC) 96-well model where biofilm is formed on plastic pegs. The new MBEC-BBF model was developed over eight days and included four rounds of partial fixation using glutaraldehyde. There was 6.14Log10cfu/cm(2) of E. faecalis and 7.71Log10cfu/cm(2) of P. aeruginosa in the final BBF. Four detergents (two enzymatic and two non-enzymatic) were tested alone or in combination with orthophthalaldehyde, glutaraldehyde or accelerated hydrogen peroxide to determine if BBF could be either removed or the bacteria within the BBF killed. None of the detergents alone could remove the biofilm or reduce the bacterial level in the BBF as determined by viable count and scanning electron microscopy. The combination of detergents and disinfectants tested provided a 3 to 5Log10 reduction in viable bacteria but no combination could provide the expected 6Log10 reduction. Our data indicated that once formed BBF was extremely difficult to eliminate. Future research using the BBF model may help develop new cleaning and disinfection methods that can prevent or eliminate BBF within endoscope channels. PMID:27345713

  16. Detailed Design Data Package item 3.9a: Cadmium buildup in off-gas lines

    International Nuclear Information System (INIS)

    Waste currently stored at the Hanford Reservation in underground double-shell and single-shell tanks is being considered for vitrification and disposal. To achieve this, Hanford is conducting a Hanford Waste Vitrification Plant Technology Development Project melter campaign. In this campaign, a requirement was identified to quantify the amount of cadmium depositing in the off-gas line between the liquid-fed ceramic melter and the submerged bed scrubber. This issue of cadmium volatility was raised due to the limited data on cadmium volatility in HLW vitrification. Prior to the start of slurry processing, the off-gas line sections were removed and inspects. Any pre-existing deposits were removed. Following the melter campaign, the lines were again removed and solids deposits were sampled and the quantity of deposits were estimated. The data presented in this package include chemical analysis of feed, glass, line deposits, in-ling off-gas stream, and SBS condensate samples. Process data includes melter feeding and glass production rates, off- gas flow rate, and plenum and off-gas stream temperatures

  17. PAD WELDING EFFECT ON CRANKSHAFT LENGTH WHILE MAKING BUILD-UP PROCESS

    Directory of Open Access Journals (Sweden)

    T. V. Vigerina

    2011-01-01

    Full Text Available The paper reveals a pad welding effect on axial sizes of a crankshaft to be built-up and a dependence of axial deformation of built-up element on an elasticity modulus, a heating temperature and thermal coefficient of linear expansion of an element and a plating, weave bead sizes. This dependence enables to forecast tensile stresses in the plating. The paper contains justification on limitation of axial deformation of the built crank due to decrease of pad welding numbers up to only one during the whole period of its lifetime and carrying out  resource-saving measures.

  18. Build-up of macroscopic eigenstates in a memory-based constrained system

    CERN Document Server

    Labousse, Matthieu; Couder, Yves; Fort, Emmanuel

    2016-01-01

    A bouncing drop and its associated accompanying wave forms a walker. Based on previous works, we show in this article that it is possible to formulate a simple theoretical framework for the walker dynamics. It relies on a time scale decomposition corresponding to the effects successively generated when the memory effects increase. While the short time scale effect is simply responsible for the walker's propulsion, the intermediate scale generates spontaneously pivotal structures endowed with angular momentum. At an even larger memory scale, if the walker is spatially confined, the pivots become the building blocks of a self-organization into a global structure. This new theoretical framework is applied in the presence of an external harmonic potential, and reveals the underlying mechanisms leading to the emergence of the macroscopic spatial organization reported by Perrard et al. (2014, Nature Commun. 5, 3219)

  19. Characterization and Quantification of Deposits Buildup and Removal in Biomass Suspension-Fired Boilers

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming;

    2010-01-01

    uptake reduction, fly ash and deposit characteristics, and deposit removal by using an advanced online deposit probe in a suspension­fired boiler using wood and straw pellets as fuel. The influence of fuel type and probe exposure time on the ash deposition rate, the heat uptake, the fly ash and deposit...... small in the tube bank region (flue gas temperature, 550­605 oC) during pure wood­firing. It was found that during suspension­firing of pure straw at low boiler load, the overall weight uptake is comparable with grate­firing, even though the amount of fly ash generated was significantly higher during...

  20. Quasi-static electric field build-up between two spherical conductors

    International Nuclear Information System (INIS)

    It has been observed that the exposure of dielectrics to electron beams can produce electric fields of sufficient magnitude to cause dielectric break-down. It is the purpose of this investigation to calculate the electric fields for two of the geometric shapes of common interest: spherical shells and cylinders. This report summarizes the work done to date on spherical dielectric shells with an inner and outer conducting surface which are traversed by an electron beam through the sphere's center. Future work will deal with a spherical shell when the beam is displaced from the sphere's center and with cylinders

  1. Non-thermal processes during the 'build-up' phase of solar flares and in absence of flares

    Science.gov (United States)

    Kane, S. R.; Pick, M.

    1976-01-01

    Hard X-ray and radio observations indicate production of non-thermal electrons as a common phenomenon of the active sun. A preliminary analysis of three hard X-ray bursts observed with the OGO-5 satellite and radio observations indicate that non-thermal particles are present in the flare region prior to the impulsive (flash) phase and also during the gradual rise and fall (GRF) bursts which are usually explained in terms of purely 'thermal' radiation. The principal difference between the non-thermal electrons observed before the flash phase and during the flash phase appears to be in their total number rather than in the hardness of their energy spectrum. Basic characteristics of the two acceleration processes are probably similar although the total energy converted into non-thermal electrons is considerably larger in the flash phase. Transient absorbing H-alpha features and filament activations are discussed in terms of their ability to produce energetic particle events and magnetic energy release.

  2. An Objective Measurement of the Build-Up of Auditory Streaming and of Its Modulation by Attention

    Science.gov (United States)

    Thompson, Sarah K.; Carlyon, Robert P.; Cusack, Rhodri

    2011-01-01

    Three experiments studied auditory streaming using sequences of alternating "ABA" triplets, where "A" and "B" were 50-ms tones differing in frequency by [delta]f semitones and separated by 75-ms gaps. Experiment 1 showed that detection of a short increase in the gap between a B tone and the preceding A tone, imposed on one ABA triplet, was better…

  3. Humidity Build-Up in a Typical Electronic Enclosure Exposed to Cycling Conditions and Effect on Corrosion Reliability

    DEFF Research Database (Denmark)

    Conseil, Helene; Gudla, Visweswara Chakravarthy; Jellesen, Morten Stendahl;

    2016-01-01

    that the exposure to cycling temperature causes significant change of internal water vapor concentration. The maximum value of humidity reached was a function of the opening size and the presence of thermal mass inside the enclosure. A pumping effect was observed due to cycling temperature, and the increase...

  4. Monolayer Phases of a Dipolar Perylene Derivative on Au(111) and Surface Potential Build-Up in Multilayers.

    Science.gov (United States)

    Niederhausen, Jens; Kersell, Heath R; Christodoulou, Christos; Heimel, Georg; Wonneberger, Henrike; Müllen, Klaus; Rabe, Jürgen P; Hla, Saw-Wai; Koch, Norbert

    2016-04-19

    9-(Bis-p-tert-octylphenyl)-amino-perylene-3,4-dicarboxy anhydride (BOPA-PDCA) is a strongly dipolar molecule representing a group of asymmetrically substituted perylenes that are employed in dye-sensitized solar cells and hold great promise for discotic liquid crystal applications. Thin BOPA-PDCA films with orientated dipole moments can potentially be used to tune the energy-level alignment in electronic devices and store information. To help assessing these prospects, we here elucidate the molecular self-assembly and electronic structure of BOPA-PCDA employing room temperature scanning tunneling microscopy and spectroscopy in combination with ultraviolet and X-ray photoelectron spectroscopies. BOPA-PCDA monolayers on Au(111) exclusively form in-plane antiferroelectric phases. The molecular arrangements, the increase of the average number of molecules per unit cell via ripening, and the rearrangement upon manipulation with the STM tip indicate an influence of the dipole moment on the molecular assembly and the rearrangement. A slightly preferred out-of-plane orientation of the molecules in the multilayer induces a surface potential of 1.2 eV. This resembles the giant surface potential effect that was reported for vacuum-deposited tris(8-hydroxyquinoline)aluminum and deemed applicable for data storage. Notably, the surface potential in the case of BOPA-PDCA can in part be reversibly removed by visible light irradiation. PMID:26991048

  5. Opting different land use for carbon buildup in soils and their bioeconomics in humid subtropics of West Bengal, India

    Directory of Open Access Journals (Sweden)

    Divy Ninad Koul

    2012-12-01

    Full Text Available Long term carbon sequestration in soil had been advocated in almost all the international forum to minimize the global warming. However, the extent of carbon storage in soil will depend on the type of vegetation it supports. The study examined different land use potentiality in sequestering carbon in soil on the basis of extent of tree component. In addition it was also investigated that how soil carbon is related with other physical and chemical parameters of the soil in different land uses. Farmers will adopt a particular land use system only if it fits in his socio-economic frame work. Hence, bioeconomics of different land uses were also calculated and compared. Extent of tree in the land use affected the physical and chemical properties of soil. The pH of the soil decreased from 6.09 to 5.09 and bulk density from 1.55 to 1.21 g/cm3 as the tree component increased. Available soil nitrogen increased from 97 to 143 kg/ha and organic carbon from 0.39 to 1.77 per cent. Out of the four soil depths surface soil had less pH, bulk density and moisture, however soil nitrogen and organic carbon was higher. Physical characters of the soil were found to be more related with organic carbon in land uses which are devoid of trees or when their number was less. However, as the tree component increases both physical and chemical component needs to be taken simultaneously to get better estimate of carbon. Agroforestry systems (agrihorticulture seems to be better land use practices as they fulfill the needs of the farmers and can also earn carbon-credits thus increasing their income by 21 per cent. 

  6. Rigging dark halos: why is hierarchical galaxy formation consistent with the inside-out build-up of thin discs?

    CERN Document Server

    Pichon, C; Kimm, T; Slyz, A; Devriendt, J; Dubois, Y

    2011-01-01

    State-of-the-art hydrodynamical simulations show that gas inflow through the virial sphere of dark matter halos is focused (i.e. has a preferred inflow direction), consistent (i.e. its orientation is steady in time) and amplified (i.e. the amplitude of advected specific angular momentum increases with time). This is a consequence of the dynamics of the cosmic web within the neighbourhood of the halo, which produces steady, angular momentum rich, filamentary inflow of cold gas. On large scales, the dynamics within neighbouring patches drives matter out of the surrounding voids, into walls and filaments before it finally gets accreted onto virialised dark matter halos. As these walls/filaments constitute the boundaries of asymmetric voids, they naturally acquire a net transverse motion, which explains the angular momentum rich nature of the later infall which comes from further away (lever effect). We argue that this large-scale driven consistency explains why cold flows are so efficient at building up thin dis...

  7. Can playing the computer game "Tetris" reduce the build-up of flashbacks for trauma? A proposal from cognitive science.

    Directory of Open Access Journals (Sweden)

    Emily A Holmes

    Full Text Available BACKGROUND: Flashbacks are the hallmark symptom of Posttraumatic Stress Disorder (PTSD. Although we have successful treatments for full-blown PTSD, early interventions are lacking. We propose the utility of developing a 'cognitive vaccine' to prevent PTSD flashback development following exposure to trauma. Our theory is based on two key findings: 1 Cognitive science suggests that the brain has selective resources with limited capacity; 2 The neurobiology of memory suggests a 6-hr window to disrupt memory consolidation. The rationale for a 'cognitive vaccine' approach is as follows: Trauma flashbacks are sensory-perceptual, visuospatial mental images. Visuospatial cognitive tasks selectively compete for resources required to generate mental images. Thus, a visuospatial computer game (e.g. "Tetris" will interfere with flashbacks. Visuospatial tasks post-trauma, performed within the time window for memory consolidation, will reduce subsequent flashbacks. We predicted that playing "Tetris" half an hour after viewing trauma would reduce flashback frequency over 1-week. METHODOLOGY/PRINCIPAL FINDINGS: The Trauma Film paradigm was used as a well-established experimental analog for Post-traumatic Stress. All participants viewed a traumatic film consisting of scenes of real injury and death followed by a 30-min structured break. Participants were then randomly allocated to either a no-task or visuospatial ("Tetris" condition which they undertook for 10-min. Flashbacks were monitored for 1-week. Results indicated that compared to the no-task condition, the "Tetris" condition produced a significant reduction in flashback frequency over 1-week. Convergent results were found on a clinical measure of PTSD symptomatology at 1-week. Recognition memory between groups did not differ significantly. CONCLUSIONS/SIGNIFICANCE: Playing "Tetris" after viewing traumatic material reduces unwanted, involuntary memory flashbacks to that traumatic film, leaving deliberate memory recall of the event intact. Pathological aspects of human memory in the aftermath of trauma may be malleable using non-invasive, cognitive interventions. This has implications for a novel avenue of preventative treatment development, much-needed as a crisis intervention for the aftermath of traumatic events.

  8. Bed mixing and leachate recycling strategies to overcome pressure drop buildup in the biofiltration of hydrogen sulfide.

    Science.gov (United States)

    Roshani, Babak; Torkian, Ayoob; Aslani, Hasan; Dehghanzadeh, Reza

    2012-04-01

    The effects of leachate recycling and bed mixing on the removal rate of H(2)S from waste gas stream were investigated. The experimental setup consisted of an epoxy-coated three-section biofilter with an ID of 8 cm and effective bed height of 120 cm. Bed material consisted of municipal solid waste compost and PVC bits with an overall porosity of 54% and dry bulk density of 0.456 g cm(-3). Leachate recycling had a positive effect of increasing elimination capacity (EC) up to 21 g S m(-3) bed h(-1) at recycling rates of 75 ml d(-1), but in the bed mixing period EC declined to 8 g S m(-3) bed h(-1). Pressure drop had a range of zero to 18 mm H(2)O m(-1) in the course of leachate recycling. Accumulation of sulfur reduced removal efficiency and increased pressure drop up to 110 mm H(2)O m(-1) filter during the bed mixing stage.

  9. Effect of Carbon Sources on the Biomass Build-Up and Degradation of Rubber Processing Industry Effluent

    Directory of Open Access Journals (Sweden)

    K. Girish

    2014-12-01

    Full Text Available Rubber processing industry effluent represents a serious environmental pollution problem especially for underground and surface water. Wastewater collected from rubber processing industry was characterized for their pollution characteristics. Analysis showed that the biological oxygen demand (BOD, chemical oxygen demand (COD, total dissolved solids (TDS, total suspended solids (TSS, total solids (TS, ammonia and phosphate were high when compared to effluent discharge standard for industrial wastewater. Four bacterial species were isolated from the wastes and were identified as Arthrobacter sp., Bacillus sp., Lactobacillus sp., and Pseudomonas sp. A bacterial consortium was constituted by mixing proportionately these four bacteria and used in effluent aerobic biotreatment. Complex carbon sources such as bagasse, corn-cob, rice straw, wheat bran, molasses, corn steep liquor, were screened for their effect on growth of the consortium constituted. Highest biomass production was in molasses followed by rice straw hydrolysate, wheat bran hydrolysate and bagasse hydrolysate. However, the inoculum grown on rice straw and wheat bran hydrolysate caused maximum degradation in terms of reduction in various parameters such as BOD, COD, TDS, TSS, NH4+ and PO43, about 70 to 80% reduction was observed. From the results of the present study it could be inferred that the constituted consortium could effectively be used for the treatment of effluents from rubber processing industry and rice straw and wheat bran hydrolysate could be used for mass production of effective consortium.

  10. Buildup of aerosol precursor gases and sulfur-induced activation of soot in nascent jet aircraft exhaust plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kaercher, B.; Hirschberg, M.M.; Fabian, P. [Muenchen Univ. (Germany). Lehrstuhl fuer Bioklimatologie und Immissionsforschung; Gerz, T. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    Research issues concerning the chemical transformation of exhaust trace gases are summarized. The photochemical evolution of NO{sub x} early in the plume is strongly coupled to plume mixing. Substantial amounts of HNO{sub 3} are generated in nascent plumes even if no NO{sub 2} is emitted. The production of H{sub 2}SO{sub 4} becomes very efficient if part of the fuel sulfur is emitted as SO{sub 3}. Each emitted soot particle can acquire 1-10% by mass fully oxidized sulfur molecules prior to binary homogeneous nucleation, if a few percent of the exhaust SO{sub x} are emitted as SO{sub 3}, indicating an important activation pathway for soot, and leading to a marked enhancement of new aerosol formation and growth rates. (author) 11 refs.

  11. Lack of social capital of the Russian business community as a build-up factors of a political risk

    OpenAIRE

    Sukiasyan Arthur Khachaturovich

    2013-01-01

    This article analyzes the characteristics of the social capital of the business community in modern Russia. Special attention is paid to the conditions of formation of the Russian business social responsibility as a key factor of accumulation of social capital. Particular attention is paid to the proper use of a business institution of social responsibility.

  12. Effects of super-powdered activated carbon pretreatment on coagulation and trans-membrane pressure buildup during microfiltration

    OpenAIRE

    Matsui, Yoshihiko; Hasegawa, Hiroki; Ohno, Koich; Matsushita, Taku; Mima, Satoru; Kawase, Yuji; Aizawa, Takako

    2009-01-01

    As a pretreatment for membrane microfiltration (MF), the use of powdered activated carbon (PAC) with a particle size much smaller than that of conventional PAC (super-powdered PAC, or S-PAC) has been proposed to enhance the removal of dissolved substances. In this paper, another advantage of S-PAC as a pretreatment for MF is described: the use of S-PAC attenuates transmembrane pressure increases during the filtration operation. The floc particles that formed during coagulation preceded by S-P...

  13. Transmission grid extensions during the build-up of a fully renewable pan-European electricity supply

    CERN Document Server

    Becker, Sarah; Andresen, Gorm B; Schramm, Stefan; Greiner, Martin

    2013-01-01

    Spatio-temporal generation patterns for wind and solar photovoltaic power in Europe are used to investigate the future rise in transmission needs with an increasing penetration of these variable renewable energy sources (VRES) on the pan-European electricity system. VRES growth predictions according to the official National Renewable Energy Action Plans of the EU countries are used and extrapolated logistically up to a fully VRES-supplied power system. We find that keeping today's international net transfer capacities (NTCs) fixed over the next forty years reduces the final need for backup energy by 13% when compared to the situation with no NTCs. An overall doubling of today's NTCs will lead to a 26% reduction, and an overall quadrupling to a 33% reduction. The remaining need for backup energy is due to correlations in the generation patterns, and cannot be further reduced by transmission. The main investments in transmission lines are due during the ramp-up of VRES from 15% (as planned for 2020) to 80%. Add...

  14. A recent build-up of atmospheric CO2 over Europe. Part 1: observed signals and possible explanations

    OpenAIRE

    Ramonet, Michael; Ciais, Philippe; Aalto, Tuula; Aulagnier, Céline; Chevallier, Frédéric; Cipriano, Domenico; Conway, Thomas J.; Haszpra, Laszlo; Kazan, Victor; Meinhardt, Frank; Paris, Jean-Daniel; Schmidt, Martina; Simmonds, Peter; Xueref-Rémy, Irène; Necki, Jaroslaw N.

    2011-01-01

    We analysed interannual and decadal changes in the atmospheric CO2 concentration gradient (ΔCO2) between Europe and the Atlantic Ocean over the period 1995–2007. Fourteen measurement stations are used, with Mace-Head being used to define background conditions. The variability of ΔCO2 reflects fossil fuel emissions and natural sinks activity over Europe, as well as atmospheric transport variability. The mean ΔCO2 increased by 1–2 ppm at Eastern European stations (∼30% growth), between 1990–199...

  15. Rigging dark halos: why is hierarchical galaxy formation consistent with the inside-out build-up of thin discs?

    OpenAIRE

    Pichon, C.; Pogosyan, D.; Kimm, T.; Slyz, A.; Devriendt, J; Dubois, Y.

    2011-01-01

    State-of-the-art hydrodynamical simulations show that gas inflow through the virial sphere of dark matter halos is focused (i.e. has a preferred inflow direction), consistent (i.e. its orientation is steady in time) and amplified (i.e. the amplitude of its advected specific angular momentum increases with time). We explain this to be a consequence of the dynamics of the cosmic web within the neighbourhood of the halo, which produces steady, angular momentum rich, filamentary inflow of cold ga...

  16. In-situ buildup of cosmogenic isotopes at the earth`s surface: measurement of erosion rates and exposure times

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, L.K.; Allan, G.L.; Stone, J.O.H.; Evans, J.M.; Cresswell, R.G.; Ophel, T.R. [Australian National Univ., Canberra, ACT (Australia)

    1993-12-31

    Cosmic rays produce a number of nuclides in rocks that can be used to determine the geomorphic history of surfaces. The most useful are the radioactive isotopes {sup 10}Be (t{sub 1/2} = 1.5Ma), {sup 26}Al (0.7Ma) and {sup 36}Cl (0.3Ma). Within the top 2m of the surface, these are produced principally by fast neutrons. At greater depths, production is dominated by the capture of negative muons. Measurements of a single nuclide produced in situ can be used to determine total exposure times or erosion rates. The use of multiple nuclides with different half-lives makes it possible to determine more complex histories, such as exposures interrupted by periods of burial. At the ANU, all three of the isotopes above are being used to study a variety of problems in geomorphology and paleoclimatology, although to date, most of the work has concentrated on {sup 36}Cl. The accumulation of cosmogenic {sup 36}Cl in calcite (CaCO{sub 3}) provides a means of measuring erosion rates on limestone surfaces. Sensitivity is achieved over a wide range of erosion rates due to the high production rate of {sup 36}Cl in calcite (typically greater than 30 atoms/g/yr) and a detection limit of ca. 5000 atoms/g attainable with the ANU AMS system. The method is simplified by the predominance of Ca reactions (principally spallation) over other sources of {sup 36}Cl in calcite, and the ease of sample preparation. This presentation discuss the results of measurements of {sup 36}Cl in calcite from limestone samples from Australia and Papua New Guinea. Erosion rates derived from these measurements range from 3 microns per year (Australia) to over 200 microns per year in the New Guinea highlands. 3 refs.

  17. Ash transformation and deposit build-up during biomass suspension and grate firing: Full-scale experimental studies

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming;

    2012-01-01

    of this study was to investigate ash transformation and deposition behavior in two biomass-fired boilers, firing wheat straw and/or wood. The influence of strawfiring technology (grate and suspension) on the ash transformation, deposit formation rate and deposit characteristics has been investigated. Bulk...... elemental analysis of fly ashes revealed that fly ash from suspension firing of straw has high contents of Si, K and Ca, while fly ash from straw firing on grate was rich in the volatile elements K, Cl and S. Investigations of deposit formation ratesweremade in the superheater and convective pass regions...... of the boilers by use of an advanced online deposit probe. During straw firing on grate, the measured deposit formation ratewas close to 38 g/m2/h. Data fromstraw suspension firing showed a deposit formation rate of 41 g/m2/h. The deposit formation rates during straw suspension firing and straw grate firing were...

  18. Buildup and simulation of a truck model with rear air suspension using leaf spring as guiding rod

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new kind of commercial truck is presented, which has rear air suspension using leaf spring as guiding rod instead of original leaf spring. ADAMS/Car is used as a tool to build the whole truck model. The designed truck's constant-radius cornering analysis and its ride performance simulation analysis under B class random road condition are carried out according to national experimental method standards. Compared the simulation results with the field test results indicate that performance index of the designed air suspension truck's constant-radius cornering and its ride performance meets the design requirements and reaches its prospective target. And results from simulation are similar to those from tests in value and trend, which indicates the virtual prototype is correct. The model can be used further to optinize suspension parameters and do some design work on the control system of air suspension.

  19. Modeling of gamma ray energy-absorption buildup factors for thermoluminescent dosimetric materials using multilayer perceptron neural network

    DEFF Research Database (Denmark)

    Kucuk, Nil; Manohara, S.R.; Hanagodimath, S.M.;

    2013-01-01

    V, and for penetration depths up to 10 mfp (mean-free-path). The MLPNNs have been trained by a Levenberg–Marquardt learning algorithm. The developed model is in 99% agreement with the ANSI/ANS-6.4.3 standard data set. Furthermore, the model is fast and does not require tremendous computational efforts. The estimated BA...

  20. Quantification of Ash Deposit Build-up and Removal in a Straw and Wood Suspension-Fired Boiler

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming;

    2011-01-01

    The aim of this study was to investigate ash deposit formation rate, heat uptake reduction and deposit removal by using advanced online ash deposition and sootblowing probes in a 350 MWth suspension­fired boiler, utilizing wood and straw pellets as fuel. The influence of fuel type (straw share in...

  1. Integration of Mature Adipocytes to Build-Up a Functional Three-Layered Full-Skin Equivalent

    Science.gov (United States)

    Huber, Birgit; Link, Antonia; Linke, Kirstin; Gehrke, Sandra A.; Winnefeld, Marc

    2016-01-01

    Large, deep full-thickness skin wounds from high-graded burns or trauma are not able to reepithelialize sufficiently, resulting in scar formation, mobility limitations, and cosmetic deformities. In this study, in vitro-constructed tissue replacements are needed. Furthermore, such full-skin equivalents would be helpful as in vivo-like test systems for toxicity, cosmetic, and pharmaceutical testing. Up to date, no skin equivalent is available containing the underlying subcutaneous fatty tissue. In this study, we composed a full-skin equivalent and evaluated three different media for the coculture of mature adipocytes, fibroblasts, and keratinocytes. Therefore, adipocyte medium was supplemented with ascorbyl-2-phosphate and calcium chloride, which are important for successful epidermal stratification (Air medium). This medium was further supplemented with two commercially available factor combinations often used for the in vitro culture of keratinocytes (Air-HKGS and Air-KGM medium). We showed that in all media, keratinocytes differentiated successfully to build a stratified epidermal layer and expressed cytokeratin 10 and 14. Perilipin A-positive adipocytes could be found in all tissue models for up to 14 days, whereas adipocytes in the Air-HKGS and Air-KGM medium seemed to be smaller. Adipocytes in all tissue models were able to release adipocyte-specific factors, whereas the supplementation of keratinocyte-specific factors had a slightly negative effect on adipocyte functionality. The permeability of the epidermis of all models was comparable since they were able to withstand a deep penetration of cytotoxic Triton X in the same manner. Taken together, we were able to compose functional three-layered full-skin equivalents by using the Air medium. PMID:27334067

  2. Extreme Water Loss and Abiotic O$_2$ Buildup On Planets Throughout the Habitable Zones of M Dwarfs

    CERN Document Server

    Luger, Rodrigo

    2014-01-01

    We show that terrestrial planets in the habitable zones of M dwarfs older than $\\sim$ 1 Gyr could have been in runaway greenhouses for several hundred Myr following their formation due to the star's extended pre-main sequence phase, provided they form with abundant surface water. Such prolonged runaway greenhouses can lead to planetary evolution divergent from that of Earth. During this early runaway phase, photolysis of water vapor and hydrogen/oxygen escape to space can lead to the loss of several Earth oceans of water from planets throughout the habitable zone, regardless of whether the escape is energy-limited or diffusion-limited. We find that the amount of water lost scales with the planet mass, since the diffusion-limited hydrogen escape flux is proportional to the planet surface gravity. In addition to undergoing potential desiccation, planets with inefficient oxygen sinks at the surface may build up hundreds to thousands of bars of abiotically produced O$_2$, resulting in potential false positives fo...

  3. Providing of environmental safety at construction of residential buildings in compact build-up area / Обеспечение экологической безопасности при строительстве жилых зданий в районах с плотной застройкой

    Directory of Open Access Journals (Sweden)

    Seleznev M.G. / Селезнев Михаил Георгиевич

    Full Text Available Manufacture of civil work in areas with dense building is defined by some major factors of ecological safety of inhabitants. To these factors carry also essential increase in levels of the power impurity including effect of vibration on objects and people in a wide range of frequencies (I include infraыonic and ultrasonic. In article the problem of influence of the raised level of sound pressure on on people and objects is described. The issue of influence of the increased level of sound pressure on people and objects in the areas of compact build-up area was considered. Suitability of assessment of levels of vibration influence on nearby buildings and structures at the stage of design by means of calculation way with the next changing of technological process during the implementation of construction operations was argued. / Освещена проблема влияния повышенного уровня звукового давления на людей и объекты в районах с плотной застройкой. Обоснована целесообразность оценки уровней вибровоз-действия на близлежащие здания и сооружения на стадии проектирования расчетным способом с последующим внесением изменений в технологический процесс при производстве строительных работ.

  4. Spectroscopic far ultraviolet observations of transition zone instabilities and their possible role in a pre-flare energy build-up

    Science.gov (United States)

    Brueckner, G. E.; Patterson, N. P.; Scherrer, V. E.

    1976-01-01

    Highly flare-productive newly emerging active regions are characterized by numerous small low-lying loops which frequently show a chaotic pattern. Flare activity in such a region subsides as the chaotic loop structures relax and expand into a bipolar configuration. The transition zone in such an active region is highly unstable, as shown by broadened and shifted nonthermal line profiles of medium-ionized elements like Si III, Si IV, and C IV. These transition-zone instabilities, which occur as isolated events in active regions of low flare productivity, are often observed prior to flares. Transition-zone instabilities can be traced to the footpoints of active loops and seem to be accompanied by heating of the loop. The loops vary in size and show differing degrees of activity, with the brightest and most compact ones seemingly being in a pre-flare state which results in the catastrophic energy release along the loop during a flare.

  5. Together, Slowly but Surely: The Role of Social Interaction and Feedback on the Build-Up of Benefit in Collective Decision-Making

    Science.gov (United States)

    Bahrami, Bahador; Olsen, Karsten; Bang, Dan; Roepstorff, Andreas; Rees, Geraint; Frith, Chris

    2012-01-01

    That objective reference is necessary for formation of reliable beliefs about the external world is almost axiomatic. However, Condorcet (1785) suggested that purely subjective information--if shared and combined via social interaction--is enough for accurate understanding of the external world. We asked if social interaction and objective…

  6. Characterization and Quantification of Deposit Build-up and Removal in Straw Suspension-Fired Boilers - Ph.d. thesis Muhammad Shafique Bashir

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad

    An increased use of biomass in large suspension-red power plants can be a relatively economic and potentially also efficient way to utilize biomass for heat and power production. However, large deposit formation problems limit the electrical efficiency by limiting the maximum applicable superheat...

  7. Tentative idea for build-up of Shanghai natural gas SCADA system%上海天然气SCADA系统组建设想

    Institute of Scientific and Technical Information of China (English)

    黄均义

    2000-01-01

    作者根据自己多年来从事计算机应用项目,尤其是SCADA系统项目的经验,针对"西气东输"后上海地区天然气发展的客观要求,讨论了天然气SCADA系统的有关技术问题,提出了组建天然气SCADA系统的设想.

  8. A dosimetric phantom study of dose accuracy and build-up effects using IMRT and RapidArc in stereotactic irradiation of lung tumours

    Directory of Open Access Journals (Sweden)

    Seppala Jan

    2012-05-01

    Full Text Available Abstract Background and purpose Stereotactic lung radiotherapy (SLRT has emerged as a curative treatment for medically inoperable patients with early-stage non-small cell lung cancer (NSCLC and the use of intensity-modulated radiotherapy (IMRT and volumetric modulated arc treatments (VMAT have been proposed as the best practical approaches for the delivery of SLRT. However, a large number of narrow field shapes are needed in the dose delivery of intensity-modulated techniques and the probability of underdosing the tumour periphery increases as the effective field size is decreased. The purpose of this study was to evaluate small lung tumour doses irradiated by intensity-modulated techniques to understand the risk for dose calculation errors in precision radiotherapy such as SLRT. Materials and methods The study was executed with two heterogeneous phantoms with targets of Ø1.5 and Ø4.0 cm. Dose distributions in the simulated tumours delivered by small sliding window apertures (SWAs, IMRT and RapidArc treatment plans were measured with radiochromic film. Calculation algorithms of pencil beam convolution (PBC and anisotropic analytic algorithm (AAA were used to calculate the corresponding dose distributions. Results Peripheral doses of the tumours were decreased as SWA decreased, which was not modelled by the calculation algorithms. The smallest SWA studied was 2 mm, which reduced the 90% isodose line width by 4.2 mm with the Ø4.0 cm tumour as compared to open field irradiation. PBC was not able to predict the dose accurately as the gamma evaluation failed to meet the criteria of ±3%/±1 mm on average in 61% of the defined volume with the smaller tumour. With AAA the corresponding value was 16%. The dosimetric inaccuracy of AAA was within ±3% with the optimized treatment plans of IMRT and RapidArc. The exception was the clinical RapidArc plan with dose overestimation of 4%. Conclusions Overall, the peripheral doses of the simulated lung tumours were decreased by decreasing the SWA. To achieve adequate surface dose coverage to small lung tumours with a difference less than 1 mm in the isodose line radius between the open and modulated field, a larger than 6 mm SWA should be used in the dose delivery of SLRT.

  9. Transport and build-up of tropospheric trace gases during the MINOS campaign: comparision of GOME, in situ aircraft measurements and MATCH-MPIC-data

    Directory of Open Access Journals (Sweden)

    A. Ladstätter-Weißenmayer

    2003-01-01

    Full Text Available The MINOS (Mediterranean INtensive Oxidant Study campaign was an international, multi-platform field campaign to measure long-range transport of air-pollution and aerosols from South East Asia and Europe towards the Mediterranean basin during August 2001. High pollution events were observed during this campaign. For the Mediterranean region enhanced tropospheric nitrogen dioxide (NO2 and formaldehyde (HCHO, which are precursors of tropospheric ozone (O3, were detected by the satellite based GOME (Global Ozone Monitoring Experiment instrument and compared with airborne in situ measurements as well as with the output from the global 3D photochemistry-transport model MATCH-MPIC (Model of Atmospheric Transport and CHemistry - Max Planck Institute for Chemistry. The increase of pollution in that region leads to severe air quality degradation with regional and global implications.

  10. Diurnal variation of radon measured indoors and outdoors in Grand Junction, Colorado, and Teaneck, New Jersey, and the influence that ventilation has on the buildup of radon indoors

    International Nuclear Information System (INIS)

    Continuous measurements of 222Rn were performed indoors and outdoors in two localities that differ primarily in the amount of radon source material within, under, and around building foundations. Grand Junction, Colorado, represents an area where uranium mill tailings have been incorporated into several residential and commercial structures. The radon concentration measured in the basement of a residential structure in Grand Junction known to have no uranium mill tailings within or around the foundation was 0.9 +- 0.2 pCi/liter. The presence of uranium mill tailings increased the average indoor radon concentration by at least a factor of 10 compared to the structure without tailings. Continuous radon measurements were made in a residential structure in Teaneck, NJ, which represents a locality where the 226Ra content of soil and building materials is not artificially enhanced. The daily average radon content of the basement was 0.9 +- 0.2 pCi/liter. Diurnal-like fluctuations were observed in the radon concentration in Grand Junction and Teaneck. These fluctuations were primarily a result of ventilation changes made by the occupants of the home. An algebraic equation was developed relating the equilibrium indoor and outdoor radon concentrations, the ventilation rate, and the radon flux from the 226Ra in the soil beneath the structure and in the fabrication materials of the foundation floor and walls. This relationship was used to calculate the basement ventilation rate of the house in New Jersey

  11. A dosimetric phantom study of dose accuracy and build-up effects using IMRT and RapidArc in stereotactic irradiation of lung tumours

    OpenAIRE

    Seppala Jan; Suilamo Sami; Kulmala Jarmo; Mali Pekka; Minn Heikki

    2012-01-01

    Abstract Background and purpose Stereotactic lung radiotherapy (SLRT) has emerged as a curative treatment for medically inoperable patients with early-stage non-small cell lung cancer (NSCLC) and the use of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc treatments (VMAT) have been proposed as the best practical approaches for the delivery of SLRT. However, a large number of narrow field shapes are needed in the dose delivery of intensity-modulated techniques and the prob...

  12. A dosimetric phantom study of dose accuracy and build-up effects using IMRT and RapidArc in stereotactic irradiation of lung tumours

    International Nuclear Information System (INIS)

    Stereotactic lung radiotherapy (SLRT) has emerged as a curative treatment for medically inoperable patients with early-stage non-small cell lung cancer (NSCLC) and the use of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc treatments (VMAT) have been proposed as the best practical approaches for the delivery of SLRT. However, a large number of narrow field shapes are needed in the dose delivery of intensity-modulated techniques and the probability of underdosing the tumour periphery increases as the effective field size is decreased. The purpose of this study was to evaluate small lung tumour doses irradiated by intensity-modulated techniques to understand the risk for dose calculation errors in precision radiotherapy such as SLRT. The study was executed with two heterogeneous phantoms with targets of Ø1.5 and Ø4.0 cm. Dose distributions in the simulated tumours delivered by small sliding window apertures (SWAs), IMRT and RapidArc treatment plans were measured with radiochromic film. Calculation algorithms of pencil beam convolution (PBC) and anisotropic analytic algorithm (AAA) were used to calculate the corresponding dose distributions. Peripheral doses of the tumours were decreased as SWA decreased, which was not modelled by the calculation algorithms. The smallest SWA studied was 2 mm, which reduced the 90% isodose line width by 4.2 mm with the Ø4.0 cm tumour as compared to open field irradiation. PBC was not able to predict the dose accurately as the gamma evaluation failed to meet the criteria of ±3%/±1 mm on average in 61% of the defined volume with the smaller tumour. With AAA the corresponding value was 16%. The dosimetric inaccuracy of AAA was within ±3% with the optimized treatment plans of IMRT and RapidArc. The exception was the clinical RapidArc plan with dose overestimation of 4%. Overall, the peripheral doses of the simulated lung tumours were decreased by decreasing the SWA. To achieve adequate surface dose coverage to small lung tumours with a difference less than 1 mm in the isodose line radius between the open and modulated field, a larger than 6 mm SWA should be used in the dose delivery of SLRT

  13. Heterogeneous Shallow-Shelf Carbonate Buildups in the Paradox Basin, Utah and Colorado: Targets for Increased Oil Production and Reserves Using Horizontal Drilling Techniques; SEMIANNUAL

    International Nuclear Information System (INIS)

    This report covers research activities for the second half of the second project year (October 6, 2001, through April 5, 2002). This work includes description and analysis of cores, correlation of geophysical well logs, reservoir mapping, petrographic description of thin sections, cross plotting of permeability and porosity data, and development of horizontal drilling strategies for the Little Ute and Sleeping Ute fields in Montezuma County, Colorado. Geological characterization on a local scale focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible compartmentalization, within these fields. This study utilizes representative core, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells

  14. Contribution to the build-up of a core calculation frame: comparison between ''diffusion'' and ''SPn'' operators on various configurations of the first N4 core

    International Nuclear Information System (INIS)

    The aim of this study is to compare two calculation methods implemented in the neutronic code CRONOS 2: the diffusion approximation and the SPn method. The APOLLO 2 code is used to build the multiparameter cross section libraries.The comparison is based on the first core of N4 type Chooz reactor. The rod worth and the power map have been calculated. Some recommendations about the SPn development order of flux are made and the results show that the diffusion calculations over-estimate the black rod efficiency up to 10%. (A.C.)

  15. Herschel-ATLAS: Revealing dust build-up and decline across gas, dust and stellar mass selected samples: I. Scaling relations

    CERN Document Server

    De Vis, P; Maddox, S; Gomez, H L; Clark, C J R; Bauer, A E; Viaene, S; Schofield, S P; Baes, M; Baker, A J; Bourne, N; Driver, S P; Dye, S; Eales, S A; Furlanetto, C; Ivison, R J; Robotham, A S G; Rowlands, K; Smith, D J B; Smith, M W L; Valiante, E; Wright, A H

    2016-01-01

    We present a study of the dust, stars and atomic gas (HI) in an HI-selected sample of local galaxies (z80 per cent), low stellar mass sources that appear to be in the earliest stages of their evolution. We compare this sample with dust and stellar mass selected samples to study the dust and gas scaling relations over a wide range of gas fraction (proxy for evolutionary state of a galaxy). The most robust scaling relations for gas and dust are those linked to NUV-r (SSFR) and gas fraction, these do not depend on sample selection or environment. At the highest gas fractions, our additional sample shows the dust content is well below expectations from extrapolating scaling relations for more evolved sources, and dust is not a good tracer of the gas content. The specific dust mass for local galaxies peaks at a gas fraction of ~75 per cent. The atomic gas depletion time is also longer for high gas fraction galaxies, opposite to the trend found for molecular gas depletion timescale. We link this trend to the changi...

  16. Analysis on Employment Opportunities for Medical Graduates and Their Overall Capability Buildup%医学生就业空间的多维建构研究

    Institute of Scientific and Technical Information of China (English)

    洪晓畅; 叶建

    2011-01-01

    With the deepening of the reform in economic structure and educational system, the enrollment of medical students has been expanded. As a result, the employment of medical graduates has become a heated social issue. The thesis will look into the possible future employment opportunities for medical graduates. It also analyzes factors which affect the employment of medical students, including their individual capabilities, graduate schools,family background, enrollment entities, governmental policies, employment market and other affiliated factors. It explores ways to expand the employment opportunities for medical graduates and assist medical graduates to find themselves valuable and competitive in the job market.%对医学生就业空间现状进行研究,分析影响医学生就业的诸多因素如就业竞争力不强,空间维度不宽;择业取向趋同,空间重叠率高等.建构一个包含医学生自身、学校、学生家庭、用人单位、政府、就业市场的多维就业空间,并使各维度的宽度达到最大化,最终实现医学生在广阔的就业空间中找到属于自己的位置,有效促进医学生就业.

  17. High Back Pressure on Pressure Safety Valves (PSVs) in a Flare System. Developing the Simulation model, Identifying and analyzing the back-pressure build-up

    OpenAIRE

    Sahoo, Muktikanta

    2013-01-01

    Process safety is a disciplined framework for managing the integrity of operating systems and processes handling hazardous substances. It is achieved by applying good design principles, engineering, and operating and maintenance practices. Flare systems play an important role in the safety of Oil and Gas installations by serving as outlets for emergency pressure relief in case of process upsets. Accurate and reliable estimation of system thermo-hydraulic parameters, especially system ...

  18. Build-up forces at Military Institute of Medical Radiology and Oncology for emergency medical response to some eventualities of radiological accidents - some suggestions

    International Nuclear Information System (INIS)

    Nowadays, the use of various nuclear sources in some fields of the life has brought many practical advantages in general; especially in the next several years, our country will begin construction of the first nuclear plant. However, if there were user carelessness or objective disadvantageous factors (earthquake, tsunami, etc.), that disadvantages could lead to a radiation accident or nuclear accident which causes damages not only for economy but also for public health. Therefore, the emergency response to radiation accident, especially the emergency medical response that has a great important position. To satisfy this real demand, in 1996, Vietnam Ministry of Defence made the decision to establish Center for Nuclear Medicine and Radiation Protecting (now becomes Military Institute of Medical Radiology and Oncology) with the main missions are research, applying radiation protecting methods and organizing treatments to radiation injured victims. To fulfill above main missions, with the help of Vietnam Atomic Energy Institute (VAEI), Vietnam Agency for Radiation and Nuclear Safety (VARANS), the doctors and staffs of our Institute have been participated in the international training courses and workshops that organized in Vietnam or in regional countries about emergency medical response to radiation accidents, they get valuable information, knowledge and documents from these courses and workshops. Depending on the principles of radiation emergency medical response to nuclear/ radiation accidents that International Atomic Energy Agency (IAEA) guided, and with the experience learned from other countries in Asia region, our Institute have been gradually improving on organization and curing processes for the radiation victims and also setting the preparedness for emergency medical response to radiation accidents if maybe they could occur. (author)

  19. “Waiting for the Bass to Drop”: Correlations between Intense Emotional Experiences and Production Techniques in Build-up and Drop Sections of Electronic Dance Music

    OpenAIRE

    Ragnhild Torvanger Solberg

    2014-01-01

    This study investigates the correlations between theories of intense emotional experiences and production techniques used in the electronic dance music (EDM) sections “build-up” and “drop”, which are designed to build tension and create a heightened emotional intensity among clubbers. This is done by descriptive and interpretive music analysis, where spectrograms and a schematic model visually represent the dominant production techniques. Through a theoretical framework consisting of musical ...

  20. 甲醇合成过程的建模、分析与优化%Module Build-up, Analysis and Optimization for Methanol Synthesis Process

    Institute of Scientific and Technical Information of China (English)

    孟庆军

    2005-01-01

    通过物料衡算与热量衡算,对甲醇合成反应过程进行了建模,以matlab语言为工具进行了多元非线性方程组的求解与验证,从而定量给出了各种工况下的工艺指标、各股物料参数,定量分析和探讨了各操作参数对合成反应过程的影响.

  1. Short-Term Effects of Mixed Species Fallows on Soil Organic Matter Build-Up in the Soil of Western Kenya

    International Nuclear Information System (INIS)

    The rotations of crops with Nitrogen fixing legumes in improved fallows have become central agroforestry technology for soil fertility replenishments in smallholder farms because of high cost of inorganic fertilizers. The choice of the fallow species is important because the quality of residue incorporated into the soil determines it's distribution to soil organic matter (SOM) and nitrogen (N) release. High quality residues (high N content, low lignin and polyphenols) may decompose rapidly and it's unlikely to release N in synchrony with crop demand. In contrast, residues with wide C- to- N ratio, high lignin and high polyphenols may lead to long period of N immobilization and long term build up of SOM. Field experiments were conducted on farmers' fields on a Kandiudalfic eutrudox soil in Western Kenya to determine the fate of 15 N labelled residues in soil. Maize recovered significantly less N from single calliandra residue treatment (3 to 6%). About 70% of the residue N recovered in a mize was contained in the maize grain yield. In long rains 2000, there were no significant differences in residue-N recovery among the different single mixed residue treatment. The percentage 15N recovery of residues N by maize was significantly correlated with maize grain yield. At the end of short rains 1999, legume-15N recovery from 0 to 15 cm depth ranged from 30 to 80 % and was significantly higher for calliandra both in single and mixed treatment. 15N distribution in particle size fraction showed that most calliandra N was found in >20 um fraction but N from sesbania and macroptilium was mostly in the 20 um fraction. The high recovery of N of calliandra in the soil confirms the high contribution of polyphenol rich residues to soil organic matter build up

  2. Employer Brand Buildup Based on Human Resources Management Procedure%基于人力资源管理流程的雇主品牌构建

    Institute of Scientific and Technical Information of China (English)

    冉宁

    2015-01-01

    雇主品牌能够帮助企业吸引和留住优秀的人才,在人力资源市场获得持久竞争优势。文章分析了人力资源管理与雇员聘用的状态关系,并以此为基础,从识人、选人、用人、育人、留人的人力资源管理流程方面阐述了如何构建雇主品牌。%Employer Brand can help enterprises attract and retain outstanding employees as well as enhancing lasting competitive advantages in the human resources market. This paper analyzes the relationship between human resource management and employment, and with the thus obtained results, expounds how to establish the Employer Brand from the procedure of human resource management including selecting, employing, training and retaining employees.

  3. 亚健康评价指标体系的研究与建立%Analysis and Build-up for Sub-Health Evaluating Indicator System

    Institute of Scientific and Technical Information of China (English)

    冯丽仪; 许军; 罗仁; 丘金彩; 张金华

    2011-01-01

    Objective To analyze and screen the items about sub - health evaluation system. so as to keep the more reliable, accurate and representative versions for development of sub - health rueasurement scale ( SHMS ) . Methods Totally 2 400 participants were surveyed by using the 64 - item questionnaire. Critical Ratio ( CR ) method was used for items analysis. The methods of coefficient of variation, coefficient of correlation, factor analysis, principal component analysis and Cronbach's Alpha coefficient were used to screen the 64 items. Results Score of each item in the questionnaire was statistically significantly different between the high - score - group and the low - score - group , except the overall evaluation indexes ( P < 0. 01 ). After screened by the 6 methods. 39 sub - health items were retained in the final version. Conclusion After screened by the 6 methods, the finally obtained indexes for sub - health assessment are more simple, reliable, accurate and representative, and thus the Suh - Health Measurement Scale Version 1. 0 ( SHMS V1. 0 ) is established and it is up to the request of the initial design. However, the reliability and validity of the scale still need to be tested in the future.%目的 为编制亚健康评定量表,对亚健康评价指标体系进行条目分析与筛选,保留更可靠、更准确、更有代表性的条目,最终形成亚健康评定量表.方法 应用由64个亚健康评价指标构成的自测问卷,选取2 400名研究对象进行测试.采用"临界比率"法对评价指标进行分析;采用离散趋势法、相关系数法、因子分析法、主成分分析法、Cronbach's Alpha系数法对指标进行筛选.结果 除4个总体评价指标不参与分析外,所有指标临界比率的高分组和低分组得分间均存在统计学差异(P<0.01).经6种方法筛选,最后保留39个亚健康评定指标.结论 经条目分析和筛选,最终得到更简化、可靠、准确、具有代表性的亚健康评价指标,达到最初的设计要求,形成亚健康评定量表(第1版),但未来仍需对该量表的信度、效度做进一步检验.

  4. Royal jelly-like protein localization reveals differences in hypopharyngeal glands buildup and conserved expression pattern in brains of bumblebees and honeybees

    Directory of Open Access Journals (Sweden)

    Štefan Albert

    2014-03-01

    Full Text Available Royal jelly proteins (MRJPs of the honeybee bear several open questions. One of them is their expression in tissues other than the hypopharyngeal glands (HGs, the site of royal jelly production. The sole MRJP-like gene of the bumblebee, Bombus terrestris (BtRJPL, represents a pre-diversification stage of the MRJP gene evolution in bees. Here we investigate the expression of BtRJPL in the HGs and the brain of bumblebees. Comparison of the HGs of bumblebees and honeybees revealed striking differences in their morphology with respect to sex- and caste-specific appearance, number of cells per acinus, and filamentous actin (F-actin rings. At the cellular level, we found a temporary F-actin-covered meshwork in the secretory cells, which suggests a role for actin in the biogenesis of the end apparatus in HGs. Using immunohistochemical localization, we show that BtRJPL is expressed in the bumblebee brain, predominantly in the Kenyon cells of the mushroom bodies, the site of sensory integration in insects, and in the optic lobes. Our data suggest that a dual gland-brain function preceded the multiplication of MRJPs in the honeybee lineage. In the course of the honeybee evolution, HGs dramatically changed their morphology in order to serve a food-producing function.

  5. The Relation between Galaxy Structure and Spectral Type: Implications for the Buildup of the Quiescent Galaxy Population at 0.5

    CERN Document Server

    Yano, Michael; van der Wel, Arjen; Whitaker, Katherine

    2016-01-01

    We present the relation between galaxy structure and spectral type, using a K-selected galaxy sample at 0.51.5 and significantly smaller than all other galaxy types at the same redshift. This result suggests that the suppression of star formation may be associated with significant structural evolution at z>1.5. At z<1, galaxy types with intermediate sSFRs (10^{-11.5}-10^{-10.5} yr^-1) do not have post-starburst SED shapes. These galaxies have similar sizes as older quiescent galaxies, implying that they can passively evolve onto the quiescent sequence, without increasing the average size of the quiescent galaxy population.

  6. Application Cases and Integration of Additive Manufacturing Processes into Conventional Process Chains by the Example of Tool Repair Using the Con-trolled Metal Build-Up Process

    OpenAIRE

    Wimmer, Felix

    2015-01-01

    In the first part of this thesis an overview of the most common Additive Manufacturing (AM) processes and a valid classification scheme outside of the classification of conventional ma-chining processes is presented. Advantages and shortcomings of these processes are briefly explained and application cases from the industry are given. Transitioning from the shortcom-ings of current Additive Manufacturing processes the so called “hybrid additive subtractive” processes are introduced.The concep...

  7. [The impact of load density differences on land subsidence based on build-up index and PS-InSAR technology].

    Science.gov (United States)

    Chen, Bei-Bei; Gong, Hui-Li; Li, Xiao-Juan; Lei, Kun-Chao; Lin, Zhu; Wang, Yan-Bing

    2013-08-01

    The excessive mining for underground water is the main reason inducing the land subsidence in Beijing, while, increasing of load brought by the urban construction aggravate the local land subsidence in a certain degree. As an international metropolis, the problems of land subsidence that caused by urban construction are becoming increasingly highlights, so revealing the relationship between regional load increase and the response of land subsidence also becomes one of the key problems in the land subsidence research field. In order to analyze the relationship between the load changes in construction and the land subsidence quantitatively, the present study selected the TM remote sensing image covering Beijing plain and used Erdas Modeler tool to invert the index based on building site (IBI), acquired the spatial and temporal change information in research area further; Based on results monitored by PS-InSAR (permanent scatterer interferometry) and IBI index method, and combined with the GIS spatial analysis method in the view of pixels in different scales, this paper analyzes the correlation between typical area load change and land subsidence, The conclusions show that there is a positive correlation between the density of load and the homogeneity of subsidence, especially in area which has a high sedimentation rate. Owing to such characteristics as the complexity and hysteretic nature of soil and geological structure, it is not obvious that the land subsidence caused by the increase of load in a short period. But with the increasing of local land load made by high density buildings and additional settlement of each monomer building superposed with each other, regional land subsidence is still a question that cannot be ignored and needs long-term systematic research and discussion. PMID:24159875

  8. The Coronal Global Evolutionary Model: Using HMI Vector Magnetogram and Doppler Data to Model the Buildup of Free Magnetic Energy in the Solar Corona

    Science.gov (United States)

    Fisher, G. H.; Abbett, W. P.; Bercik, D. J.; Kazachenko, M. D.; Lynch, B. J.; Welsch, B. T.; Hoeksema, J. T.; Hayashi, K.; Liu, Y.; Norton, A. A.; Dalda, A. Sainz; Sun, X.; DeRosa, M. L.; Cheung, M. C. M.

    2015-06-01

    The most violent space weather events (eruptive solar flares and coronal mass ejections) are driven by the release of free magnetic energy stored in the solar corona. Energy can build up on timescales of hours to days, and then may be suddenly released in the form of a magnetic eruption, which then propagates through interplanetary space, possibly impacting the Earth's space environment. Can we use the observed evolution of the magnetic and velocity fields in the solar photosphere to model the evolution of the overlying solar coronal field, including the storage and release of magnetic energy in such eruptions? The objective of CGEM, the Coronal Global Evolutionary Model, funded by the NASA/NSF Space Weather Modeling program, is to develop and evaluate such a model for the evolution of the coronal magnetic field. The evolving coronal magnetic field can then be used as a starting point for magnetohydrodynamic (MHD) models of the corona, which can then be used to drive models of heliospheric evolution and predictions of magnetic field and plasma density conditions at 1AU.

  9. The 3 vs 1 game build-up effectiveness examination in physical and technical tests of 11-year-old football players

    Directory of Open Access Journals (Sweden)

    Tóth jr. Janos

    2014-01-01

    Full Text Available Study aim: The aim of this study is to prove that young players who have been coached with the main focus on technical ability and player interaction, perform better when tested on physical and technical attributes.

  10. Changing the paradigm for marine data production, dissemination and validation with Collaborative Platforms. The GlobColour webservice, a prime example which leads to the integration of CWE technologies to build-up virtual research centres.

    Science.gov (United States)

    Fanton d'Andon, Odile; Martin-Lauzer, François-Regis; Mangin, Antoine; Barrot, Gilbert; Clouaire, Stephane; Sardou, Olivier; Demaria, Julien; Serra, Romain

    2015-04-01

    The GlobColour webservice provides a rich dataset of marine bio-geochemical information for research and education purposes. We report on recent evolutions to improve the functionalities of the service to access EO and in-situ data and check information quality. In addition, a new concept, the Collaborative Platform, support the processing of bespoke information for remote users. At the root of the service is an integrated and automated production chain, processing not only EO satellite data but also in-situ measurements from bio-Argo floats. This production chain provides daily updated bio-geochemical data and performs automated data analysis (merging of sensors, temporal and spatial binning). The GlobColour webservice has been recently upgraded to provide improved navigation and selection capabilities. These evolutions were necessary as the catalogue of EO products has been significantly increased, with many new parameters, new spatial resolution (1 km over Europe in addition to 4 km global products) and projections (rectangular grid in addition to sinus grid). The validation and quality control of the information is essential to demonstrate the fitness-for-purpose of the service. Match-ups between in-situ measurements and EO data are a key element to establish the validity of the information. The standard approach is to perform these match-ups off-line using a database of in-situ measurements, and report the results in a validation document. Two innovations are introduced which greatly increase the value for the user: • An interactive navigation tool allows a detailed analysis the results of the match-ups, with temporal and geographical selection capabilities. Background information for each match-up can be easily retrieved, both for in-situ (measurement identification) and for satellite data (context retrieval, providing information such as cloud coverage and spatial variability). This allows users to get a better insight into the validity of the retrieved data for their particular applications. • Match-ups using real-time EO data and data collected from bio-Argo floats are processed automatically on-the-fly. • This is possible because quality control of the bio-Argo float data is also automated. A dedicated interface has been set-up to monitor the whole fleet of Bio-Argo floats, and access detailed information from each acquired profile. Finally, a Collaborative Platform has been developed to support R&D activities in parallel to the standard production chain, enabling users to work remotely within a dedicated production environment in order to develop new algorithms and methods. The Collaborative Platform is based on a Collaborative Working Environment, a secured IT environment mixing hardware and software elements. It provides access to raw data, to processing and storage facilities, to specific applicative software (e.g. visualisation and post-processing tools). In addition, collaborative tools to exchange data, information and ideas between participants (through forums, web-conferencing…) contribute to create a "Virtual Research Centre" preparing future evolutions of the service. Acknowledgements: This research received funding from the following projects: • MCGS project funded by the Fonds Unique Interministériel, French regional funds PACA and Bretagne, the Fonds Européen de Développement Régional • FP7 Copernicus projects OSS2015 (grant n° 282723) and E-AIMS (grant n° 312642). • The French EQUIPEX project NAOS

  11. Two improvements to the dynamic wake meandering model: including the effects of atmospheric shear on wake turbulence and incorporating turbulence build-up in a row of wind turbines

    DEFF Research Database (Denmark)

    Keck, Rolf-Erik; de Mare, Martin Tobias; Churchfield, Matthew J.;

    2015-01-01

    agreement with the reference data. A quantitative comparison between the mean flow field of the DWM model with and without the suggested improvements, to that of the AL model, shows that the root-mean-square difference in terms of wind speed and turbulence intensity is reduced on the order of 30% and 40......%, respectively, by including the proposed corrections for a row of eight turbines. Furthermore, it is found that the root-mean-square difference between the AL model and the modified DWM model in terms of wind speed and turbulence intensity does not increase over a row of turbines compared with the root-mean-square...

  12. Appliance of AC Servo System in Build-up Force Standard Machine Based on FM354%基于FM354的交流伺服系统在机械比对力机上的应用

    Institute of Scientific and Technical Information of China (English)

    张振洲; 马宏发

    2007-01-01

    针对机械比对力机的工艺和控制要求,详细介绍了西门子SIMODRIVE 611A交流伺服驱动系统在机械比对力机上的应用.利用高性能的伺服定位模块FM354,控制交流伺服驱动系统,满足机械比对力机对速度、力矩和大调速范围的要求,使力机满足国家称重传感器检定规程(JJG669-90)和称重传感器生产检测要求.

  13. Build-up SQL Server 2005 Based Hospital Data Warehouse and Data Mining%基于SQL Server 2005数据仓库构建与数据挖掘

    Institute of Scientific and Technical Information of China (English)

    贺海平; 李捷; 贺明

    2008-01-01

    采用Microsoft SQL Server 2005作为构建数据仓库的技术平台,针对医院的住院、门诊和病历首页的历史记录,构建了医院的数据仓库实例,为医院管理者提供多层次、多角度的数据挖掘和分析,增强医院决策和合理配置医疗资源起到积极作用.

  14. 加强军校技能教员队伍建设的思考%Strengthen the Buildup of Skill -teacher Contigent, Lay a Solid Foundation of Military Skill Teaching

    Institute of Scientific and Technical Information of China (English)

    董洪强; 胡国新; 高博

    2012-01-01

    军事技能教员队伍建设是一项关系到军事人才培养和国防现代化进程的基础性工程.必须加强技能教员队伍建设,从思想上锤炼其爱岗敬业、甘于奉献的高尚品质,通过建立和完善各项制度,充分调动一线技能教员教学积极性,并通过“三支队伍”建设不断提高教员队伍素质,增强教员队伍活力和发展后劲,为培养高素质新型军事人才打牢军事技能教学基石.

  15. A review on tectonic record of strain buildup and stress release across the Andean forearc along the Gulf of Guayaquil-Tumbes basin (GGTB) near Ecuador-Peru border

    OpenAIRE

    2013-01-01

    Gravimetric and geologic data show that the reactivation of the Neogene Interandean depression and/or the ~75 - 65 Ma ophiolite suture into the modern dynamic of the Andes controlled the Gulf of Guayaquil Tumbes basin (GGTB) location and evolution during the past 1.8 - 1.6 Myr at least. Depending on whether the remobilization occurred along the in- terandean depression or the ophiolite suture, the GGTB evolved trough pure or simple shear mechanisms, respectively. Because the GGTB exhibits an ...

  16. 复合树脂核材料与牙本质黏结强度的实验研究%Experimental study of bonding strength between resin composite direct core build-up materials and dentin in vitro

    Institute of Scientific and Technical Information of China (English)

    俞长路; 陈梅梅; 叶茂昌

    2012-01-01

    目的 比较使用3种不同牙本质黏结剂时,2种复合树脂核材料与精细粒度车针预备的牙本质之间的微拉伸黏结强度.方法 本实验使用的2种复合树脂核材料为Bisfil-core和Luxacore,3种黏结剂为ONE-STEPRPLUS、Contax和ibond,各对应的组别为BO组、LO组、BC组、LC组、Bi组和Li组.18颗人类磨牙用于本实验,每组3颗牙齿.所有牙齿均去除冠部釉质,暴露出完整的表浅牙本质,并用精细粒度金钢砂车针预备牙本质.然后按照各厂家的说明完成黏结剂的应用并用2种核材料分别修复牙冠.牙齿在37℃的自来水中保存24 h后,沿与黏结面垂直的方向片切成厚约0.7 mm的薄片,然后修整黏结面,使其面积大约在1.0 mm2.样本在MTS Synergie100材料测试机上进行黏结强度测试,所得数据用方差分析和LSD检验进行统计学处理.结果 各组的黏结强度分别为BO组(27.34±6.52)MPa、LO组(36.49±11.74)MPa、BC组(23.78±9.03)MPa、LC组(34.35±13.35)MPa、Bi组(29.12±7.99)MPa、Li组(32.63±8.17)MPa.统计学分析显示,黏结强度的差异在不同黏结剂之间无统计学意义,在不同的核材料之间差异有统计学意义.结论 3种黏结剂均可以满足临床需要,流动性复合树脂核材料可以显著提高黏结强度.%Objective To compare the microtensile bonding strength between two resin composite direct core build - up materials and dentin prepared with a superfine - grit diamond bur when using three different dentin adhesives. Methods Two kinds of resin composite core build - up materials, Bisfil - core and Luxacore, and three kinds of adhesives, ONE - STEP O RPLUS, Contax and ibond, were used in this stud)'. The six corresponding groups were BO, LO, BC, LC, Bi, Li, respectively. Eighteen human molarswere randomly divided into six groups with three teeth in each group in this stud)'. The coronal enamel of all teeth was removed and the superficial dentin was exposed, which were then prepared with a superfine - grit diamond bur. The dentin adhesives were applied to dentin surface according to manufacturers 'instructions. The teeth were then restored with two resin composite direct core build - up materials and stored in tap water at 370C for 24 hours. After that, the teeth were sectioned perpendicular to the bonded surface into slices approximately 0. 7mm thickness. Each slice was then trimmed into an hourglass shape to provide a 1. 0 mm2 bonded area. The specimens were subjected to microtensile bond strength testing on MTS SynergielOO testing machine. Data were analyzed by ANOVA and LSD test. Results Bonding strength of each group as follows: BO (927.34 ±6.52 )MPa,LO( 36.49 ±11.74 ) MPa,BC ( 23.78 ±9.03 )MPa,LC( 34.35 ±13.35 )MPa,Bi( 29. 12 ±7.99 )MPa,Li( 32.63 ± 8. 17 )MPa. The difference is not significant in dentin adhesives but significant in resin composite direct core build - up materials. Conclusion  All three dentin adhesives can meet the demand of clinical practice. A flowable resin composite core material can enhance the bonding strength significantly.

  17. HerMES: deep number counts at 250, 350, and 500 microns in the COSMOS and GOODS-N fields and the build-up of the cosmic infrared background

    CERN Document Server

    Béthermin, M; Ilbert, O; Conley, A; Lagache, G; Amblard, A; Arumugam, V; Aussel, H; Berta, S; Bock, J; Boselli, A; Buat, V; Casey, C M; Castro-Rodríguez, N; Cava, A; Clements, D L; Cooray, A; Dowell, C D; Eales, S; Farrah, D; Franceschini, A; Glenn, J; Griffin, M; Hatziminaoglou, E; Heinis, S; Ibar, E; Ivison, R J; Kartaltepe, J S; Levenson, L; Magdis, G; Marchetti, L; Marsden, G; Nguyen, H T; O'Halloran, B; Oliver, S J; Omont, A; Page, M J; Panuzzo, P; Papageorgiou, A; Pearson, C P; Pérez-Fournon, I; Pohlen, M; Rigopoulou, D; Roseboom, I G; Rowan-Robinson, M; Salvato, M; Schulz, B; Scott, Douglas; Seymour, N; Shupe, D L; Smith, A J; Symeonidis, M; Trichas, M; Tugwell, K E; Vaccari, M; Valtchanov, I; Vieira, J D; Viero, M; Wang, L; Xu, C K; Zemcov, M

    2012-01-01

    ABRIGED Herschel/SPIRE has provided confusion limited maps of deep fields at 250, 350, and 500um, as part of the HerMES survey. Due to confusion, only a small fraction of the Cosmic Infrared Background can be resolved into individually-detected sources. Our goal is to produce deep galaxy number counts and redshift distributions below the confusion limit, which we then use to place strong constraints on the origins of the cosmic infrared background and on models of galaxy evolution. We individually extracted the bright SPIRE with a method using the positions, the flux densities, and the redshifts of the 24um sources as a prior, and derived the number counts and redshift distributions of the bright SPIRE sources. For fainter SPIRE sources, we reconstructed the number counts and the redshift distribution below the confusion limit using the deep 24um catalogs associated with photometric redshift and information provided by the stacking of these sources into the deep SPIRE maps. Finally, by integrating all these c...

  18. 基于3D CAD MineStar 软件的胶东大尹格庄金矿三维数字实体模型的建立%The Buildup of the 3D Entity Model Based on the Software of 3D CAD MineStar in Dayin’gezhuang Gold Deposit,Jiaodong Region

    Institute of Scientific and Technical Information of China (English)

    孙书彬; 吴洋; 姜新吉; 张瑞忠

    2015-01-01

    Based on analyzing the character of 3D CAD MineStar software,applying AotoCAD software as well as aided design software for 3D mine,according to actual situation of the mine,entity model with 3D digital mock-up for geology and mine system at the Dayin’gezhuang gold mine was established,which had improved the information,production intelligent and automation level,production intelligence information and automation level.Moreover,it is meaningful and can provide significant direction for improving the speed and precision of the prospecting,mining quantity computation,aided design and safety management.%在分析3D CAD MineStar 软件特点的基础上,结合矿山实际情况,应用 AutoCAD 软件和三维矿山辅助设计软件 MineStar,建立了大尹格庄金矿的三维数字地质实体模型和采矿系统实体模型。三维数字实体模型的建立提高了大尹格庄金矿的信息化、生产智能化和自动化水平,对于建设大尹格庄金矿数字矿山平台,提高探矿和矿量计算的速度与精度、辅助设计和安全管理等具有重要的经济价值和指导意义。

  19. Erosion amount build-up of unconformity and its structural significance:Taking Cretaceous T.unconformity in southern Beier Depression as an example%不整合面剥蚀量恢复及其构造意义——以贝南凹陷T22不整合面为例

    Institute of Scientific and Technical Information of China (English)

    夏世强; 刘景彦

    2012-01-01

    文中综合应用声波时差法和地震反射结构外延法对T22不整合面进行剥蚀趋势恢复,进而探讨其构造活动强度及对油气运移和成藏的影响.研究表明,剥蚀厚度沿主干断裂边缘及古隆起斜坡带呈NE-SW向分布,最大剥蚀厚度位于南部苏德尔特断隆东缘,可达900m,紧邻斜坡的低洼处剥蚀较小,约150m.剥蚀量大小和分布形态与区域构造活动密切相关,南屯组末期,由于受来自NW-SE方向挤压应力作用,造成先存的同沉积断裂发生构造反转.反转断裂沟通底部油源向上运移,在断隆高部位,由于剥蚀较大而造成早期油气散失,而斜坡部位则由于反转适度,有利于油气的保存,其中贝8、贝3等5口井出现工业油流,其余4口亦出现良好的油气显示.因此,预测贝南斜坡带是下一步油气勘探的重要区带.

  20. 4-[18F]Fluorophenylpiperazines by Improved Hartwig-Buchwald N-Arylation of 4-[18F]fluoroiodobenzene, Formed via Hypervalent λ3-Iodane Precursors: Application to Build-Up of the Dopamine D4 Ligand [18F]FAUC 316

    Directory of Open Access Journals (Sweden)

    Fabian Kügler

    2014-12-01

    Full Text Available Substituted phenylpiperazines are often neuropharmacologically active compounds and in many cases are essential pharmacophores of neuroligands for different receptors such as D2-like dopaminergic, serotoninergic and other receptors. Nucleophilic, no-carrier-added (n.c.a. 18F-labelling of these ligands in an aromatic position is desirable for studying receptors with in vivo molecular imaging. 1-(4-[18F]Fluorophenylpiperazine was synthesized in two reaction steps starting by 18F-labelling of a iodobenzene-iodonium precursor, followed by Pd-catalyzed N-arylation of the intermediate 4-[18F]fluoro-iodobenzene. Different palladium catalysts and solvents were tested with particular attention to the polar solvents dimethylformamide (DMF and dimethylsulfoxide (DMSO. Weak inorganic bases like potassium phosphate or cesium carbonate seem to be essential for the arylation step and lead to conversation rates above 70% in DMF which is comparable to those in typically used toluene. In DMSO even quantitative conversation was observed. Overall radiochemical yields of up to 40% and 60% in DMF and DMSO, respectively, were reached depending on the labelling yield of the first step. The fluorophenylpiperazine obtained was coupled in a third reaction step with 2-formyl-1H-indole-5-carbonitrile to yield the highly selective dopamine D4 ligand [18F]FAUC 316.

  1. Naval trends in ASEAN: is there a new arms race?

    OpenAIRE

    Jones, Frank Curtis

    1995-01-01

    Global military spending is decreasing. However this trend does not apply to some regions of the world, specifically Southeast Asia. This thesis describes the ongoing naval arms buildup in this region and examines why it is occurring when the rest of the world is decreasing military spending. Next, this thesis asks if this arms build-up is dangerous. Unlike many other arms races around the world, the Southeast Asian build-up is not particularly dangerous because of the parallel development of...

  2. Testing geopressured geothermal reservoirs in existing wells. Final report P. R. Girouard Well No. 1, Lafayette Parish, Louisiana. Volume II. Well test data

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    The following data from the reopening of an abandoned well are presented: reservoir pressure drawdown and buildup data, Institute of Gas Technology test data, Insitute of Gas Technology sample log, reservoir fluid analysis, produced gas/water ratio, chemical analysis procedures, surface flow data, third party sampling and reports, sand detectors charts, and Horner-type buildup data. (MHR)

  3. Environmental Degradation of Solar Reflectors

    Science.gov (United States)

    Bouquet, F. L.

    1985-01-01

    Report presents results of study of atmospheric degradation of large solar reflectors for power generators. Three general types of reflective surfaces investigated. Report also describes computer buildup and removal (by rain and dew) of contamination from reflectors. Data used to determine effects of soil buildup and best method and frequency of washing at various geographic locations.

  4. Equipment and piping for nuclear power plants, test and research reactors, and nuclear installations

    International Nuclear Information System (INIS)

    The standard provides rules for testing the following welding operations: welding of ferritic pearlitic steels, welding of corrosion resistant austenitic steels, welding of components made of corrosion resistant austenitic steels and ferritic pearlitic steels, build-up welding of groove faces, and build-up welding of corrosion protecting layers

  5. Misfolded proteins, endoplasmic reticulum stress and neurodegeneration

    OpenAIRE

    Rao, Rammohan V.; Bredesen, Dale E.

    2004-01-01

    The accumulation of misfolded proteins (e.g. mutant or damaged proteins) triggers cellular stress responses that protect cells against the toxic buildup of such proteins. However, prolonged stress due to the buildup of these toxic proteins induces specific death pathways. Dissecting these pathways should be valuable in understanding the pathogenesis of, and ultimately in designing therapy for, neurodegenerative diseases that feature misfolded proteins.

  6. Take-Off. De opbouw van de Nederlandse luchtstrijdkrachten 1945-1973

    NARCIS (Netherlands)

    van der Vegt, Q.J.

    2013-01-01

    There has been little academic focus on the build-up of the Dutch Air Force after the Second World War. The aim of this study is to identify the key developments in the build-up and sustainment of the Dutch air force between 1945 and 1973 and to answer the question as to which factors and actors sha

  7. Improvement of the gamma-ray transport model the point kernel attenuation method

    International Nuclear Information System (INIS)

    The gamma-ray buildup factor is a multiplicative factor which corrects the response of non-collided photons to include the contribution of the scattered photons. Buildup factors are very important data implemented in Point kernel codes for use in shield design. We propose in this study, a new evaluation of gamma-ray buildup factors which takes into account all the interaction modes of photons with matter, in the energy range of 15 KeV to 10 MeV, for materials of atomic number Z=1 to Z=92. The analytical representation, called Geometric Progression, has been applied to reproduce the buildup factors calculated within a few percent. This formula can be used to interpolate the buildup factors over the full range of distance, energy and atomic number. We tackle also the calculation of buildup factors in stratified shields and propose a new approximate formula to calculate the buildup factors in these complex configurations. (authors). 77 refs., 55 figs., 33 tabs

  8. Improvement of the gamma-ray transport model the point kernel attenuation method; Amelioration de la modelisation du transport des gamma suivant la methode de l`attenuation en ligne droite

    Energy Technology Data Exchange (ETDEWEB)

    Assad, A.

    1995-12-01

    The gamma-ray buildup factor is a multiplicative factor which corrects the response of non-collided photons to include the contribution of the scattered photons. Buildup factors are very important data implemented in Point kernel codes for use in shield design. We propose in this study, a new evaluation of gamma-ray buildup factors which takes into account all the interaction modes of photons with matter, in the energy range of 15 KeV to 10 MeV, for materials of atomic number Z=1 to Z=92. The analytical representation, called Geometric Progression, has been applied to reproduce the buildup factors calculated within a few percent. This formula can be used to interpolate the buildup factors over the full range of distance, energy and atomic number. We tackle also the calculation of buildup factors in stratified shields and propose a new approximate formula to calculate the buildup factors in these complex configurations. (authors). 77 refs., 55 figs., 33 tabs.

  9. Fiber-optic polymer residue monitor

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, K.B.; Jarecki, R.L. Jr. [Sandia National Labs., Albuquerque, NM (United States); Dalton, T.J. [Digital Semiconductor, Hudson, MA (United States)

    1998-10-01

    Semiconductor processing tools that use a plasma to etch polysilicon or oxides produce residue polymers that build up on the exposed surfaces of the processing chamber. These residues are generally stressed and with time can cause flaking onto wafers resulting in yield loss. Currently, residue buildup is not monitored, and chambers are cleaned at regular intervals resulting in excess downtime for the tool. In addition, knowledge of the residue buildup rate and index of refraction is useful in determining the state of health of the chamber process. The authors have developed a novel optical fiber-based robust sensor that allows measurement of the residue polymer buildup while not affecting the plasma process.

  10. Fenofibrate

    Science.gov (United States)

    ... blood and to increase the amount of HDL (high-density lipoprotein; a type of fatty substance that decreases the risk of heart disease) in the blood. Build-up of cholesterol and fats along the walls of the arteries ( ...

  11. Cellulitis

    Science.gov (United States)

    The health care provider will perform a physical exam. This may reveal: Redness, warmth, and swelling of the skin Possible drainage, if there is a buildup of pus ( abscess ) with the skin infection Swollen glands (lymph nodes) ...

  12. Sodium blood test

    Science.gov (United States)

    ... liver Adrenal glands not making enough of their hormones ( Addison disease ) Buildup in urine of waste product from fat breakdown (ketonuria) Syndrome of inappropriate antidiuretic hormone secretion (antidiuretic hormone is released from an abnormal ...

  13. Genetics Home Reference: juvenile Batten disease

    Science.gov (United States)

    ... somehow disrupt the function of cellular structures called lysosomes . Lysosomes are compartments in the cell that normally digest and recycle different types of molecules. Lysosome malfunction leads to a buildup of fatty substances ...

  14. Maple syrup urine disease

    Science.gov (United States)

    ... break down the amino acids leucine, isoleucine, and valine. This leads to a buildup of these chemicals ... levels of the amino acids leucine, isoleucine, and valine. People with this condition must remain on a ...

  15. Hydrocephalus

    Science.gov (United States)

    ... buildup of too much cerebrospinal fluid in the brain. Normally, this fluid cushions your brain. When you have too much, though, it puts harmful pressure on your brain. Hydrocephalus can be congenital, or present at birth. ...

  16. Composition of microfouling on aluminium and fibre glass panels exposed in Agatti waters (Lakshadweep Island)

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; Sankaran, P.D.; Wagh, A.B.

    Rate of microfouling build-up was high during the initial periods of exposure of test surfaces but decreased with the increasing duration. Fibre glass surfaces showed higher deposition than those of aluminium. Carbohydrates and lipids were the major...

  17. Cirrhosis

    Science.gov (United States)

    ... leading cause of death in the United States, accounting for nearly 32,000 deaths each year. More ... stomach, or both an enlarged spleen, called splenomegaly mental confusion due to a buildup of toxins that ...

  18. Radioactivity Calculations

    Science.gov (United States)

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  19. Medline Plus

    Full Text Available ... artery unimpeded. However, a process called atherosclerosis can cause a buildup of cholesterol and cells and other ... lack of oxygen to the heart muscle and cause angina. If the inner wall of a coronary ...

  20. Pressure transient analysis methods for bounded naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C-C; Raghavan, R.; Reynolds, A.C.; Serra, K.

    1985-06-01

    New methods for analyzing drawdown and buildup pressure data obtained at a well located in an infinite, naturally fractured reservoir were presented recently. In this work, the analysis of both drawdown and buildup data in a bounded, naturally fractured reservoir is considered. For the bounded case, the authors show that five possible flow regimes may be exhibited by drawdown data. They delineate the conditions under which each of these five flow regimes exists and the information that can be obtained from each possible combination of flow regimes. Conditions under which semilog methods can be used to analyze buildup data are discussed for the bounded fractured reservoir case. New Matthews-Brons-Hazebroek (MBH) functions for computing the average reservoir pressure from buildup data are presented.

  1. Numerical model of a stationary Alfven flow and magnetohydrodynamic flows close to it in coaxial canals in the presence of a longitudinal magnetic field

    International Nuclear Information System (INIS)

    Stationary transonic super-Alfven, subsonic super-Alfven, supersonic sub-Alfven, and Alfven magnetohydrodynamic flows, obtained by numerical modeling of their build-up processes, in coaxial canals in the presence of longitudinal magnetic field have been considered

  2. Diet - chronic kidney disease

    Science.gov (United States)

    ... this special diet to limit the buildup of waste products in the body. Limiting fluids between dialysis ... up when the kidneys no longer function well. Dangerous heart rhythms may result, which can lead to ...

  3. Development of arctic wind technology

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Marjaniemi, M.; Antikainen, P. [VTT Energy, Espoo (Finland)

    1998-10-01

    The climatic conditions of Lapland set special technical requirements for wind power production. The most difficult problem regarding wind power production in arctic regions is the build-up of hard and rime ice on structures of the machine

  4. Epilepsy in Adults with TSC

    Medline Plus

    Full Text Available ... centers in a large city and/or an academic center near you (for a listing of epilepsy ... onset seizures. Occasionally, the onset of seizures will result from a buildup of pressure in the brain ...

  5. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... system. This pressure buildup can cause blood to flow backward from the liver into the veins of ... does the procedure work? A TIPS reroutes blood flow in the liver and reduces abnormally high blood ...

  6. Genetics Home Reference: cystic fibrosis

    Science.gov (United States)

    ... Me Understand Genetics Home Health Conditions cystic fibrosis cystic fibrosis Enable Javascript to view the expand/collapse boxes. Print All Open All Close All Description Cystic fibrosis is an inherited disease characterized by the buildup ...

  7. Genetics Home Reference: mitochondrial complex III deficiency

    Science.gov (United States)

    ... chemical called lactic acid in the body (lactic acidosis). Some affected individuals also have buildup of molecules ... Additional Information & Resources MedlinePlus (4 links) Encyclopedia: Lactic Acidosis Encyclopedia: Metabolic Acidosis Health Topic: Genetic Brain Disorders ...

  8. Trace Contaminant Monitor for Air in Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A need exists for analyzers that can measure trace contaminants in air on board spacecraft. Toxic gas buildup can endanger the crew particularly during long...

  9. Paint-Bonding Improvement for 2219 Aluminum Alloy

    Science.gov (United States)

    Daech, Alfred F.; Cibula, Audrey Y.

    1987-01-01

    Bonding of adhesives and primers to 2219 aluminum alloy improved by delaying rinse step in surface-treatment process. Delaying rinse allows formation of rougher surface for stronger bonding and greater oxide buildup.

  10. Mounting technique for pressure transducers minimizes measurement interferences

    Science.gov (United States)

    Lanham, R. N.; Taylor, C. E.; Balmer, C. E.; Hwang, C.

    1975-01-01

    Miniaturized transducers are fabricated from commercially available four-arm semiconductor gages; transducers are connected as bridge circuit and mounted on internal face of small diaphragm. Jacket made of conductive plastic may be needed to avoid buildup or static charges.

  11. Pulse radiolysis of tetraalkylammonium hydroxides in alkaline solution containing oxygen

    International Nuclear Information System (INIS)

    In the pulse radiolysis of aqueous oxygenated solutions of tetraalkylammonium hydroxides there is a build-up of ozonide ion lasting up to 100 μs after the pulse. The build-up does not occur in solutions containing a twenty fold (reactivity) excess of N2O to O2. The influence of various concentrations of tetraalkylammonium cations, oxygen and different reactivity ratios of N2O to O2 on the build-up of ozonide ion after the pulse was investigated. The reaction rates of O2-and O- with peroxy radicals and organic cations, respectively, control the nature of the observed build-up and decay of ozonide ion. (author)

  12. Ventriculoperitoneal shunt - discharge

    Science.gov (United States)

    ... in the brain. This buildup of brain and spinal cord fluid (cerebrospinal fluid, or CSF) and pressure causes the brain tissue to press (become compressed) against the skull. Too much pressure or pressure that is present ...

  13. Production of dimethylsulphide during the seasonal anoxia off Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Shenoy, D.M.; Sujith, K.B.; Gauns, M.; Patil, S.; Sarkar, Amit; Naik, H.; Narvekar, P.V.; Naqvi, S.W.A.

    of hydrogen sulphide. However, total dimethylsulphoniopropionate, total dimethylsulphoxide and methanethiol concentrations were quite low and unlikely to account for the DMS build-up through presently known pathways of DMS production. While there are several...

  14. Medline Plus

    Full Text Available ... wall of an artery. This material includes fat, cholesterol, and other substances. Eventually, the material builds up and a plaque is formed, narrowing the artery. When the build-up is ...

  15. Medline Plus

    Full Text Available ... cholesterol, and other substances. Eventually, the material builds up and a plaque is formed, narrowing the artery. When the build-up is severe, a clot could block the vessel ...

  16. Protecting Your Hearing

    Medline Plus

    Full Text Available ... will typically complain that their ear feels blocked up, they feel like they have cotton in their ... the cochlea. The cause may be earwax build-up, fluid, or a punctured eardrum. Medical or surgical ...

  17. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... they have increased pressure in the portal vein system. This pressure buildup can cause blood to flow ... the hepatic vein to identify the portal venous system. Access is then gained from the hepatic vein ...

  18. Bile duct obstruction

    Science.gov (United States)

    ... the liver. It contains cholesterol, bile salts, and waste products such as bilirubin . Bile salts help your ... can lead to life-threatening infection and a dangerous buildup of bilirubin. If the blockage lasts a ...

  19. Simple Signal Source based Micro Controller

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Using micro controller, DAC and Multi-periods syn-thesis, we can buildup a very simple signal source with precisefrequency, amplitude and waveform. Wave parameters can beprogrammed in advance. The circuit can satisfy some special re-quirements.

  20. Kidney Failure and Vascular Disease

    Science.gov (United States)

    ... narrows due to plaque buildup (stenosis) and blood flow is restricted to even one kidney, high blood pressure (hypertension) ... can be detected by physical examination or special tests: A physician’s ... through narrowed renal arteries. An Abdominal Ultrasound examination ...

  1. Modelling ionising radiation induced defect generation in bipolar oxides with gated diodes; Modelisation de la generation de defauts crees par irradiation dans les oxydes de transistors bipolaires: caracterisation par la methode ''diodes controlees par grille''

    Energy Technology Data Exchange (ETDEWEB)

    Barnaby, H.J.; Cirba, C.; Schrimpf, R.D. [Vanderbilt Univ., Dept. of ECE (United States); Kosier, St. [VTC Inc. Bloomington, MN (United States); Fouillat, P.; Montagner, X. [Bordeaux Univ., Lab. IXL, CNRS UMR 5818, 33 (France)

    1999-07-01

    Radiation-induced oxide defects that degrade electrical characteristics of bipolar junction transistor (BJTs) can be measured with the use of gated diodes. The buildup of defects and their effect on device radiation response are modeled with computer simulation. (authors)

  2. Safe venting of ''red oil'' runaway reactions

    International Nuclear Information System (INIS)

    Calorimetry testing of Tri-n-butyl phosphate (TBP) saturated with strong nitric acid was performed to determine the relationship between vent size and pressure buildup in the event of a runaway reaction. These experiments show that runaway can occur in an open system, but that even when runaway is induced in the TBP/HN03 system, dangerous pressure buildup will be prevented with practical vent size

  3. Statistical patterns in the location of natural lightning

    OpenAIRE

    İnan, Umran Savaş; Zoghzoghy, F.G; Cohen,M.B; Said, R.K

    2013-01-01

    Lightning discharges are nature’s way of neutralizing the electrical buildup in thunderclouds. Thus, if an individual discharge destroys a substantial fraction of the cloud charge, the probability of a subsequent ?ash is reduced until the cloud charge separation rebuilds. The temporal pattern of lightning activity in a localized region may thus inherently be a proxy measure of the corresponding timescales for charge separation and electric ?eld buildup processes. We present a s...

  4. Studies of Beam Induced Electron Cloud Resonances in Dipole Magnetic Fields

    OpenAIRE

    Calvey, J. R.; Hartung, W.; Makita, J.; Venturini, M.

    2016-01-01

    The buildup of low energy electrons in an accelerator, known as electron cloud, can be severely detrimental to machine performance. Under certain beam conditions, the beam can become resonant with the cloud dynamics, accelerating the buildup of electrons. This paper will examine two such effects: multipacting resonances, in which the cloud development time is resonant with the bunch spacing, and cyclotron resonances, in which the cyclotron period of electrons in a magnetic field is a multiple...

  5. Application of game theory to the interface between militarization and environmental stewardship in the Mariana Islands

    OpenAIRE

    Marler, Thomas E.; Wiecko, Greg; Moore, Aubrey

    2012-01-01

    We recently described threats to the terrestrial biological resources on the Mariana islands of Guam and Tinian resulting from the large-scale buildup of military operations. Attitudes that view these military buildup plans in a zero sum context whereby the positives of greater security and improved local economy can be attained only with corresponding negatives of environmental destruction are prevalent. We argue these attitudes oversimplify the complicated interactions between military oper...

  6. Assessing Discount Rate for a Project Financed Entirely with Equity Capital

    Directory of Open Access Journals (Sweden)

    Nicoleta Vintila

    2007-09-01

    Full Text Available Estimating discount rate for an investment project is one of the most challenging tasks incapital budgeting. In this paper we discuss different kind of models for cost of equity capital proposed infinance literature (static CAPM, conditional CAPM, APT, build-up model, focusing especially on advantagesand disadvantages of using each of them. In the final section, we estimate the discount rate fora certain project financed entirely with equity capital, using a version of build-up model.

  7. Consistent seasonal snow cover depth and duration variability over the Western Himalayas (WH)

    Indian Academy of Sciences (India)

    Dan Singh; Vikas Juyal; Vikas Sharma

    2016-10-01

    Precipitation in solid form, i.e., snow, during winter season over theWestern Himalayas (WH) leads to the build-up of seasonal snow cover. Seasonal snow cover build-up (snow cover depth and duration) largely depends on atmospheric variables such as temperature, precipitation, radiation, wind, etc. Integrated(combined) influence of atmospheric variables on seasonal snow cover gets reflected in terms of spatial and temporal variability in seasonal snow cover build-up pattern. Hence spatial and temporal variability of seasonal snow cover build-up can serve as a good indicator of climate change in high altitude mountainousregions like the WH. Consistent seasonal snow cover depth and duration, delay days and early melt days of consistent seasonal snow cover at 11 stations spread across different mountain ranges over the WH were analyzed. Mean, maximum and percentiles (25th, 50th, 75th, 90th and 95th) of consistent seasonal snow cover depth and duration show decline over the WH in the recent past 2–3 decades. Consistent seasonal snow cover is found to melt early and snow cover build-up pattern is found to show changes over the WH. Decline in consistent seasonal snow cover depth, duration and changing snow cover buildup pattern over the WH in recent decades indicate that WH has undergone considerable climate changeand winter weather patterns are changing in the WH.

  8. Incorporating process variability into stormwater quality modelling.

    Science.gov (United States)

    Wijesiri, Buddhi; Egodawatta, Prasanna; McGree, James; Goonetilleke, Ashantha

    2015-11-15

    Process variability in pollutant build-up and wash-off generates inherent uncertainty that affects the outcomes of stormwater quality models. Poor characterisation of process variability constrains the accurate accounting of the uncertainty associated with pollutant processes. This acts as a significant limitation to effective decision making in relation to stormwater pollution mitigation. The study undertaken developed three theoretical scenarios based on research findings that variations in particle size fractions 150 μm during pollutant build-up and wash-off primarily determine the variability associated with these processes. These scenarios, which combine pollutant build-up and wash-off processes that takes place on a continuous timeline, are able to explain process variability under different field conditions. Given the variability characteristics of a specific build-up or wash-off event, the theoretical scenarios help to infer the variability characteristics of the associated pollutant process that follows. Mathematical formulation of the theoretical scenarios enables the incorporation of variability characteristics of pollutant build-up and wash-off processes in stormwater quality models. The research study outcomes will contribute to the quantitative assessment of uncertainty as an integral part of the interpretation of stormwater quality modelling outcomes. PMID:26179783

  9. Well testing for radially heterogeneous reservoirs under single and multiphase flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.G.; Reynolds, A.C. [Univ. of Tulsa, OK (United States)

    1997-03-01

    In this work, the authors examine the behavior of pressure-transient data for single and multiphase flow in radially heterogeneous reservoirs. To illustrate multiphase flow behavior in these systems, they focus on heterogeneous gas-condensate reservoirs; however, they also consider other multiphase flow problems. It is well known that in some instances, e.g., water injection/falloff in homogeneous reservoirs, pressure-transient data from buildup (or falloff) tests cannot be obtained by superposition of drawdown (injection) pressure responses. In fact, drawdown and buildup reflect properties in different regions of the reservoir. This behavior is common to most occurrences of multiphase reservoir flow and is exaggerated in the presence of radial heterogeneity. This theoretical work describes the information contained in transient pressure derivative data and explains the fundamental difference in behavior between multiphase drawdown and buildup pressure-transient data in radially heterogeneous reservoirs. The authors show that multiphase buildup data may be treated like single-phase buildup data, but drawdown data is most indicative of properties in that region of the reservoir where mobility is changing most rapidly with time.

  10. Well testing for heterogeneous reservoirs under single and multiphase flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.G.; Reynolds, A.C. [Univ. of Tulsa, OK (United States)

    1995-12-31

    In this work, we examine the behavior of pressure transient data for single and multiphase flow in heterogeneous reservoirs. In order to illustrate multiphase flow behavior in these systems, we focus on heterogeneous gas condensate reservoirs, however, we also consider other multiphase flow problems. It is well known that in some instances, e. g., water injection/falloff in homogeneous reservoirs, pressure transient data from buildup (or falloff) tests cannot be obtained by superposition of drawdown (injection) pressure responses. In fact, drawdown and buildup reflect properties in different regions of the reservoir. This behavior is common to most occurrences of multiphase reservoir flow, and is exaggerated in the presence of radial heterogeneity. This theoretical work describes the information contained in transient pressure derivative data, and explains the fundamental difference in behavior between multiphase drawdown and buildup pressure transient data in radially heterogeneous reservoirs. We show that whereas multiphase buildup data may be treated like single-phase buildup data, drawdown data is most indicative of properties in that region of the reservoir where mobility is changing most rapidly with time.

  11. Recent findings on sinks for sulfide in gravity sewer networks

    DEFF Research Database (Denmark)

    Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

    2006-01-01

    Sulfide buildup in sewer networks is associated with several problems, including health impacts, corrosion of sewer structures and odor nuisance. In recent years, significant advances in the knowledge of the major processes governing sulfide buildup in sewer networks have been made. This paper...... summarizes this newly obtained knowledge and emphasizes important implications of the findings. Model simulations of the in-sewer processes important for the sulfur cycle showed that sulfide oxidation in the wetted biofilm is typically the most important sink for dissolved sulfide in gravity sewers. However......, sulfide emission and thereby potential hydrogen sulfide buildup in the sewer atmosphere is of particular importance in sewers constructed with large diameter pipes, in sewers constructed with steep slopes and in sewers conveying low pH wastewater. Precipitation of metal sulfides is only important when...

  12. Electrohydrodynamic pumping in cable pipes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Crowley, J.M.; Chato, J.C.

    1983-02-01

    Many oil-insulated electric power cables are limited by heat buildup caused in part by the low thermal conductivity of the oil. Circulation of the oil is known to reduce the cable temperature, but can lead to excessive pressure buildup on long cables when using conventional pumping methods. An alternate pumping method using distributed electric fields to avoid this pressure buildup is described. Electrohydrodynamic (EHD) pumping was studied both theoretically and experimentally for possible application in underground cable cooling. Theoretical studies included both analytical and finite-element analysis of the flow patterns driven by travelling electric fields. Experimentally, flow rates in a cable-pipe model were measured under a wide variety of operating conditions. Theory and experiment are in agreement for velocities below 10 cm/s, but higher velocities could not be reached in the experiment, due to increased electroconvection and, possibly, turbulence.

  13. Upflow bioreactor with septum and pressure release mechanism

    Science.gov (United States)

    Hansen, Conly L.; Hansen, Carl S.; Pack, Kevin; Milligan, John; Benefiel, Bradley C.; Tolman, C. Wayne; Tolman, Kenneth W.

    2010-04-20

    An upflow bioreactor includes a vessel having an inlet and an outlet configured for upflow operation. A septum is positioned within the vessel and defines a lower chamber and an upper chamber. The septum includes an aperture that provides fluid communication between the upper chamber and lower chamber. The bioreactor also includes means for releasing pressure buildup in the lower chamber. In one configuration, the septum includes a releasable portion having an open position and a closed position. The releasable portion is configured to move to the open position in response to pressure buildup in the lower chamber. In the open position fluid communication between the lower chamber and the upper chamber is increased. Alternatively the lower chamber can include a pressure release line that is selectively actuated by pressure buildup. The pressure release mechanism can prevent the bioreactor from plugging and/or prevent catastrophic damage to the bioreactor caused by high pressures.

  14. Analysis of finite conductivity fractures intercepting multilayer reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C.; Raghavan, R.; Reynolds, A.C.

    1982-09-01

    This paper presents the analytical and numerical results of an examination into the response of a fractured well in a multi-layered reservoir. The analytical solutions derived are new and served three functions. First, they enabled the verification of the numerical solutions. Second, they provided information on the structure of the solution, and thus increased physical understanding. Third, they suggested a method whereby the authors were able to correlate multi-layer solutions with the single-layer solutions. The authors show that under certain circumstances the well response of wells draining multilayer reservoirs can be correlated with single-layer reservoirs. They also find that the ratio of the fracture height to the fracture length has an influence on well performance. This influence is discussed. The authors also consider the analysis of buildup data following a short producing time. They show that the multi-layer buildup solutions can be correlated with the single-layer buildup solutions.

  15. Analysis of finite conductivity fractures intercepting multilayer reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C.O.; Reynolds, A.C.; Raghavan, R.

    1982-01-01

    The response of a fractured well in a multilayered reservoir is the primary subject of this study. Both analytic and numeric results are presented. The analytic solutions derived are new and served 3 important functions. First, they enable verification of the numeric solutions used in this study. Second, they provided information on the structure of the solution, and thus increased physical understanding. Third, they suggested a method for correlating multilayer solutions with the single-layer solutions. The well response of wells draining multilayer reservoirs can be correlated with single-layer reservoirs. It also was found that the ratio of the fracture height to fracture length has an influence on well performance. The analysis of buildup data following a short producing time is considered. It is shown that the multilayer buildup solutions can be correlated with the single-layer buildup solutions. 21 references.

  16. The Exploration Portable Electrostatic Detector (xPED)

    Science.gov (United States)

    Jackson, Telana L.; Farrell, William M.

    2012-01-01

    Astronauts and rovers, while exploring dynamic environments, can experience charge buildup through Tribo-charging (contact electrification). Charge levels can become substantially high. especially in areas where photoelectric and plasma currents are reduced (e.g. lunar polar crater). Tribo-charging in areas that have little to no charge dissipative path can be severe, leaving an astronaut or roving object to remain charged for extended periods of time. Charge buildup on space suits and/or rovers is expected to present significant hazards to missions, such as electrostatic discharge and arcing, dust adhesion to space suits/equipment, and destruction of equipment. The avoidance of hazards associated with charge buildup is critical for future NASA missions to near earth objects, the Moon and Mars. The Exploration Portable Electrostatic Device (xPED) will allow astronauts to determine their charge state, and also characterize the electrical environment from their excursions. xPED would benefit manned, as well as robotic missions.

  17. Assessment of performance of UV sterilizer for room air bacteria.

    Science.gov (United States)

    Joshi, P V

    2002-02-01

    Paper presents a technique for performance of UV sterilizer for room air bacteria. Patterns of decay of room air bacteria concentration during sterilization and build-up there after as a function of time is studied. Decay process seems to follow exponential pattern. Half-lives during decay are estimated. For single sterilizer unit with a dose of 16 W the decay half-life is around 8.6 min. For the dose of 32 W (2 sterilizers), half-life is estimated to be 6.18 min. The removal rates of room air bacteria due to sterilizer are compared with the natural decay of aerosols at steady state. The importance of decay half-life in the assessment has been stated. The bacteria concentration buildup process after putting off the sterilizers seems to be sigmoidal in nature. The buildup half-life is estimated to be around 53 min for present experimental conditions.

  18. Direct Numerical Modeling of E-Cloud Driven Instability of a Bunch Train in the CERN SPS

    International Nuclear Information System (INIS)

    The simulation package WARP-POSINST was recently upgraded for handling multiple bunches and modeling concurrently the electron cloud buildup and its effect on the beam, allowing for direct self-consistent simulation of bunch trains generating, and interacting with, electron clouds. We have used the WARP-POSINST package on massively parallel supercomputers to study the buildup and interaction of electron clouds with a proton bunch train in the CERN SPS accelerator. Results suggest that a positive feedback mechanism exists between the electron buildup and the e-cloud driven transverse instability, leading to a net increase in predicted electron density. Electron clouds have been shown to trigger fast growing instabilities on proton beams circulating in the SPS and other accelerators. So far, simulations of electron cloud buildup and their effects on beam dynamics have been performed separately. This is a consequence of the large computational cost of the combined calculation due to large space and time scale disparities between the two processes. We have presented the latest improvements of the simulation package WARP-POSINST for the simulation of self-consistent ecloud effects, including mesh refinement, and generation of electrons from gas ionization and impact at the pipe walls. We also presented simulations of two consecutive bunches interacting with electrons clouds in the SPS, which included generation of secondary electrons. The distribution of electrons in front of the first beam was initialized from a dump taken from a preceding buildup calculation using the POSINST code. In this paper, we present an extension of this work where one full batch of 72 bunches is simulated in the SPS, including the entire buildup calculation and the self-consistent interaction between the bunches and the electrons.

  19. In-vivo dosimetry for field sizes down to 6 × 6 mm2 in shaped beam radiosurgery with microMOSFET.

    Science.gov (United States)

    Sors, A; Cassol, E; Latorzeff, I; Duthil, P; Sabatier, J; Lotterie, J A; Redon, A; Berry, I; Franceries, X

    2014-09-01

    The aim of this study is to evaluate microMOSFET as in-vivo dosimeter in 6 MV shaped-beam radiosurgery for field sizes down to 6 × 6 mm2. A homemade build-up cap was developed and its use with microMOSFET was evaluated down to 6 × 6 mm2. The study with the homemade build-up cap was performed considering its influence on field size over-cover occurring at surface, achievement of the overall process of electronic equilibrium, dose deposition along beam axis and dose attenuation. An optimized calibration method has been validated using MOSFET in shaped-beam radiosurgery for field sizes from 98 × 98 down to 18 × 18 mm2. The method was detailed in a previous study and validated in irregular field shapes series measurements performed on a head phantom. The optimized calibration method was applied to microMOSFET equipped with homemade build-up cap down to 6 × 6 mm2. Using the same irregular field shapes, dose measurements were performed on head phantom. MicroMOSFET results were compared to previous MOSFET ones. Additional irregular field shapes down to 8.8 × 8.8 mm2 were studied with microMOSFET. Isocenter dose attenuation due to the homemade build-up cap over the microMOSFET was near 2% irrespective of field size. Our results suggested that microMOSFET equipped with homemade build-up cap is suitable for in-vivo dosimetry in shaped-beam radiosurgery for field sizes down to 6 × 6 mm2 and therefore that the required build-up cap dimensions to perform entrance in-vivo dosimetry in small-fields have to ensure only partial charge particle equilibrium.

  20. Microfractures due to overpressures caused by thermal cracking in well-sealed Devonian reservoirs, deep Alberta basin, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, X.M. [Dept. de Exploracion, Maraven, S.A., Caracas (Venezuela); Mountjoy, E.W. [McGill Univ., Montreal (Canada)

    1996-08-01

    Microfractures (< 1 mm in width) filled with reservoir bitumen crosscut all diagenetic phases in the upper 200 m of the partially to completely dolomitized Upper Devonian (Leduc Formation) Strachan buildup and other buildups in the deep Alberta basin. They display three patterns: (1) subhorizontal, extending from intraskeletal pores and perpendicular to sub-vertical fractures, (2) random in the matrix, and (3) radial around vugs and fossil molds. Subhorizontal microfracturing is most common and radial is the least common. Overpressuring caused by thermal cracking of crude oil to gas during burial can produce most of the characteristics exhibited by these microfractures: their association with all pore types, bitumen fillings and relatively late diagenetic timing. Microfractures are restricted to isolated buildups below depths of about 3800 m in the Alberta Basin. Thermal cracking of crude oil to gas during burial is also indicated by finely and coarsely deformed lamellar textures of the reservoir bitumen that fill the microfractures in the Strachan buildup. Also, the stress field was modified by tectonic compression during the Late Cretaceous and Early Tertiary Laramide orogeny. Pressures generated during thermal cracking of oil together with tectonic compression probably created the microfractures in the isolated and effectively sealed reservoirs. The increased horizontal stresses resulted in subhorizontal microfractures, whereas rare radial and random microfractures formed under conditions of more uniform stress. The lack of microfractures in adjacent gas-bearing and updip buildups along the Rimbey-Meadowbrook reef trend is likely due to the connection of these buildups to a regional conduit system in the underlying Cooking Lake platform, preventing them from developing sufficient overpressures.

  1. Effective management of heat transfer fluid flash point temperatures using a light-ends removal kit (LERK)

    OpenAIRE

    Christopher Ian Wright

    2014-01-01

    Heat transfer fluids (HTF) need to be regularly sampled to assess the extent of thermal degradation, oxidative state, the accumulation of short-chained light-ends and contamination by intrinsic or extrinsic particles. The build-up of light-ends in a HTF system presents a potential fire hazard. A light-ends removal kit (LERK) enables light-ends to be removed continuously, helping to push-up flash point temperatures. In the current case, the concentration of light-ends started to build-up in th...

  2. Studies of Beam Induced Electron Cloud Resonances in Dipole Magnetic Fields

    CERN Document Server

    Calvey, J R; Makita, J; Venturini, M

    2016-01-01

    The buildup of low energy electrons in an accelerator, known as electron cloud, can be severely detrimental to machine performance. Under certain beam conditions, the beam can become resonant with the cloud dynamics, accelerating the buildup of electrons. This paper will examine two such effects: multipacting resonances, in which the cloud development time is resonant with the bunch spacing, and cyclotron resonances, in which the cyclotron period of electrons in a magnetic field is a multiple of bunch spacing. Both resonances have been studied directly in dipole fields using retarding field analyzers installed in the Cornell Electron Storage Ring (CESR). These measurements are supported by both analytical models and computer simulations.

  3. Surface modifications of stainless steel to minimise contamination in mass spectrometers

    Science.gov (United States)

    Abda, J.; Douce, D.; Jones, G.; Skeldon, P.; Thompson, G. E.

    2015-12-01

    The effect of electrochemically grown and vapour deposited coatings on the build-up of contamination on stainless steel surfaces in the electrospray ionisation source of a mass spectrometer is investigated, together with their influence on the robustness of the instrument response. Quantification of the contamination build-up on flat samples, using white light interferometry, allowed the identification of the most beneficial treatments. Coating with electrochemically-grown anodic oxide and cathodic oxide films and amorphous carbon films doped with silicon or nitrogen resulted in reduced contamination compared with the uncoated stainless steel surface, and provided improved robustness of the instrument response.

  4. Suspension-Firing of Biomass

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming;

    2012-01-01

    This paper is the second of two papers, describing probe measurements of deposit buildup and removal (shedding), conducted in a 350 MWth suspension-fired boiler, firing straw and wood. Investigations of deposit buildup and shedding have been made by use of an advanced online deposit probe and a...... sootblowing probe. The influences of feedstock (i.e., straw share in wood), flue gas temperature (600−1050 °C), probe surface temperature (500 and 600 °C), and probe exposure time on deposit shedding have been quantified. Quantification of naturally occurring deposit shedding and deposit shedding during plant...

  5. Damage accumulation in He implanted SiC at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Barbot, Jean Francois; Declemy, Alain; Beaufort, Marie-France [Institut Prime (UPR 3346), Departement Physique et Mecanique des Materiaux, CNRS, Universite de Poitiers, ENSMA, 86962 Futuroscope Chasseneuil (France)

    2013-01-15

    The defect accumulation in helium-implanted 4H-SiC was studied in a large range of temperatures through the elastic strain build-up determined by using X-ray diffraction measurements. The interstitial type defects formation and accumulation result in the strain build-up that was modelled with a multi-step damage accumulation. The gradient of strain imputed to the ion implantation processes leads to the additional step of defect accumulation where the nuclear energy loss is maximal. This phenomenon is enhanced when the formation of bubbles takes place. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. γ-ray shielding effect of various building materials

    International Nuclear Information System (INIS)

    It is necessary to know the γ-ray attenuation coefficients and the dose buildup factors for various building materials in order to evaluate the γ-ray shielding factor of the residential houses in the reactor accident. As a matter of fact, however, there is few information about these values. This report describes measurements of the linear attenuation coefficients and dose buildup factors for the typical building materials used in Japan and estimation of the γ-ray shielding effects of these materials. (author)

  7. Effects of noncontact cleaners on transparent solar materials

    Energy Technology Data Exchange (ETDEWEB)

    Hampton, H.L.; Lind, M.A.

    1979-04-01

    A brief study has been undertaken to evaluate the performance of noncontact cleaning agents for use on solar collectors. Several techniques are used to compare cleansing agents which have been recommended by their respective manufacturers for cleaning solar mirrors. Wetting and residue buildup properties are evaluated for over 50 of these commercially available cleaners. The wetting properties of each cleaner are evaluated by measuring the growth of the contact area of a constant volume drop as a function of time. Losses due to residue buildup are solar weighted and considered equally with the wetting parameters and cost figures to construct a figure of merit for cleaner comparison.

  8. The combination of photocatalysis and ozonolysis as a new approach for cleaning 2,4-dichlorophenoxyaceticacid polluted water.

    Science.gov (United States)

    Müller, T S; Sun, Z; Kumar, G; Itoh, K; Murabayashi, M

    1998-04-01

    Treatment of 2,4-D polluted waters with photocatalysis leads to the buildup of high concentrations of the long living intermediate 2,4-DCP. A new approach using a combination of ozonolysis and photocatalysis gave better degradation results with lower intermediate concentrations. The advantages of photocatalysis giving a constant decline in TOC and of ozonolysis giving no buildup of high intermediate concentrations were combined. Degradation data of 2,4-D for photocatalysis, ozonolysis and the combination of both for different pH ranges are given. Data on the main intermediate 2,4-DCP are given for the three different approaches.

  9. Take-Off. De opbouw van de Nederlandse luchtstrijdkrachten 1945-1973

    OpenAIRE

    van der Vegt, Q.J.

    2013-01-01

    There has been little academic focus on the build-up of the Dutch Air Force after the Second World War. The aim of this study is to identify the key developments in the build-up and sustainment of the Dutch air force between 1945 and 1973 and to answer the question as to which factors and actors shaped these developments. This study describes that process from the perspectives of foreign policy, domestic policy and the institutional perspective. At the level of multilateral dynamics, the Cold...

  10. Beam induced electron cloud resonances in dipole magnetic fields

    Science.gov (United States)

    Calvey, J. R.; Hartung, W.; Makita, J.; Venturini, M.

    2016-07-01

    The buildup of low energy electrons in an accelerator, known as electron cloud, can be severely detrimental to machine performance. Under certain beam conditions, the beam can become resonant with the cloud dynamics, accelerating the buildup of electrons. This paper will examine two such effects: multipacting resonances, in which the cloud development time is resonant with the bunch spacing, and cyclotron resonances, in which the cyclotron period of electrons in a magnetic field is a multiple of bunch spacing. Both resonances have been studied directly in dipole fields using retarding field analyzers installed in the Cornell Electron Storage Ring. These measurements are supported by both analytical models and computer simulations.

  11. Towards an All-Polymer Biosensor for Early Alzheimer's Disease

    DEFF Research Database (Denmark)

    Christiansen, Nikolaj Ormstrup; Heegaard, Niels

    Alzheimer's disease (AD) is quickly evolving into one of the biggest and most costly health issues in Europe and the United States. AD is a protein misfolding disease, caused by accumulation of abnormally folded β-amyloid and tau protein in the brain. The build-up of protein is believed to degene......Alzheimer's disease (AD) is quickly evolving into one of the biggest and most costly health issues in Europe and the United States. AD is a protein misfolding disease, caused by accumulation of abnormally folded β-amyloid and tau protein in the brain. The build-up of protein is believed...

  12. Shift designs for freight handling personnel at air cargo terminals

    DEFF Research Database (Denmark)

    Rong, Aiying; Grunow, Martin

    2009-01-01

    This paper presents an integrated mixed integer linear programming (MILP) model for determining manpower requirements and related personnel shift designs for the build-up and break-down of the unit load devices (ULDs) at the air cargo terminal to minimize manpower costs. To utilize the manpower...... resources efficiently, we implement a new mechanism for demand leveling. In addition, we consider the qualification hierarchy between build-up and break-down workers. A case study based on the real-life data shows that the model is useful for manpower planning at air cargo terminals and the integrated...

  13. Recent trends in salinity control for soilless growing systems management

    NARCIS (Netherlands)

    Katsoulas, N.; Voogt, W.

    2014-01-01

    The consequences of closed hydroponic systems, the impact of salinity build-up on crop yield and product quality are reviewed. Soilless cultivation, especially in closed-loop systems offers a great option for water saving in greenhouses. Capture and recycling of the drainage will considerably improv

  14. Phytoremediation: A green technology to remove environmental pollutants

    Science.gov (United States)

    Land, surface water, and ground water worldwide, are increasingly affected by contaminations from industrial, research experiments, military, and agricultural activities either due to ignorance, lack of vision, carelessness, or high cost of waste disposal and treatment. The rapid build-up of toxic p...

  15. A model for foam formation, stability, and breakdown in glass-melting furnaces

    NARCIS (Netherlands)

    Schaaf, J. van der; Beerkens, R.G.C.

    2006-01-01

    A dynamic model for describing the build-up and breakdown of a glass-melt foam is presented. The foam height is determined by the gas flux to the glass-melt surface and the drainage rate of the liquid lamellae between the gas bubbles. The drainage rate is determined by the average gas bubble radius

  16. Novel Search Algorithms for a Mid-IR Spectra Database of Cotton Contaminants

    Science.gov (United States)

    Cotton lint contamination from the cotton plant itself and transportation debris is a serious problem for the cotton industry. Buildup of foreign substances on processing machinery can lead to decreased production rates and decreased yarn quality. The USDA has been developing a mid-IR spectra data...

  17. Effect of closed v. intermittent-flow respirometry on hypoxia tolerance in the shiner perch Cymatogaster aggregata

    DEFF Research Database (Denmark)

    Snyder, S; Nadler, L E; Bayley, J S;

    2016-01-01

    hypoxia tolerance in closed respirometry is consistent with additional stress, caused by a build-up of ammonia and carbon dioxide and a faster rate in dissolved oxygen decline. The results indicate that these two methods of determining hypoxia tolerance in aquatic organisms are not comparable, and that...

  18. The effect of a fiber reinforced cavity configuration on load bearing capacity and failure mode of endodontically treated molars restored with CAD/CAM resin composite overlay restorations

    NARCIS (Netherlands)

    G.T. Rocca; C.M. Saratti; M. Cattani-Lorente; A.J. Feilzer; S. Scherrer; I. Krecji

    2015-01-01

    Objectives To evaluate the fracture strength and the mode of failure of endodontically treated molars restored with CAD/CAM overlays with fiber reinforced composite build-up of the pulp chamber. Methods 40 Devitalized molars were cut over the CEJ and divided into five groups (n = 8). The pulp chambe

  19. On the Design and Development of WEBSEE: A Web-Based Senior Exit Exam for Value-Added Assessment of a CIS Program

    Science.gov (United States)

    Kamoun, Faouzi; Selim, Said

    2008-01-01

    Higher education institutions are becoming increasingly engaged in assessing their programs in order to enhance student learning outcomes. States, accreditation bodies and various organizations are calling upon institutions to buildup their accountability towards student learning. Accordingly, multiple assessment methods (both direct and indirect)…

  20. Geodetic measurements at sea floor spreading centers

    Science.gov (United States)

    Spiess, F. N.

    1978-01-01

    A network of 8 or more precision transponder units mounted on the sea floor and interrogated periodically from an instrument package towed near bottom through the area to provide the necessary spatial averaging could provide a practical system for observing the pattern of buildup of strain at intermediate and fast spreading centers.

  1. Structure and tectonic evolution of the northeastern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Ramana, M.V.; Krishna, K.S.; Ramprasad, T.; Desa, M.; Subrahmanyam, V.; Sarma, K.V.L.N.S.

    , (3) identification of the Cretaceous magnetic smooth zone and the boundary of the late Cretaceous crust in the distal part of the Bengal Fan, (4) structure and origin of the 85 degrees E Ridge, seismic stratigraphy, the presence of carbonate buildup...

  2. A new conceptual model for the fate of lignin in decomposing plant litter

    NARCIS (Netherlands)

    T. Klotzbücher; K. Kaiser; G. Guggenberger; C. Gatzek; K. Kalbitz

    2011-01-01

    Lignin is a main component of plant litter. Its degradation is thought to be critical for litter decomposition rates and the build-up of soil organic matter. We studied the relationships between lignin degradation and the production of dissolved organic carbon (DOC) and of CO2 during litter decompos

  3. ASSESSMENT OF YOUNG CHILDREN'S POTENTIAL PESTICIDE EXPOSURE FOLLOWING A RESIDENTIAL PESTICIDE APPLICATION - PART I. STUDY DESIGN: EXPOSURE OF CHILDREN AND TOYS

    Science.gov (United States)

    Semi-volatile pesticides such as chlorpyrifos can be dynamic in nature; once applied, they can migrate spatially and concentrations can build-up in and on objects and surfaces. Such pesticides are frequently used in U.S. households. Children within these homes may be exposed ...

  4. In-line monitor of plutonium holdup in glovebox filters

    International Nuclear Information System (INIS)

    An in-line filter holdup monitoring system has been designed and installed in the Los Alamos Scientific Laboratory (LASL) Plutonium Processing Facility to detect plutonium buildup in a glovebox exhaust filter. The filter is located on top of a glovebox in which plutonium and uranium oxide and carbon are blended, milled, and prepared for making advanced fast breeder reactor (FBR) fuel

  5. Collapsible pistons for light-gas guns

    Science.gov (United States)

    Teng, R. N.

    1973-01-01

    Moving and expandable parts of gun consist of pump-tube diaphragm, piston, launch-tube diaphragm, and saboted projectile. As a result of improved piston design, pressure cycle has been significantly improved by smoother buildup, increasing muzzle velocities up to 50%.

  6. Investigation of Operation of the Cryotronic Relaxation Oscillations Generator in the Supercooled Helium

    International Nuclear Information System (INIS)

    The investigation results of operation of the cryotronic relaxation oscillations generator (CROG) in the supercooled helium have been given. The processes that take place in helium during its warming up have been described and the CROG operation peculiarities have been shown. The helium temperature build-up time and CROG frequency under different values of helium supercooling have been measured

  7. A large extra-abdominal prevesical pseudo-cyst in a newborn with posterior urethral valves.

    NARCIS (Netherlands)

    Binkhorst, M.; Gier, R.P.E. de

    2010-01-01

    A male newborn is described, in whom a large extra-abdominal prevesical pseudo-cyst as well as prune-belly features were present, both of which were supposedly secondary to posterior urethral valves. It is postulated that the subvesical obstruction caused pressure build-up in the urinary tract, foll

  8. Iceland's Economic Eruption and Meltdown

    DEFF Research Database (Denmark)

    Nielsson, Ulf; Torfason, Bjarni K.

    2012-01-01

    background that lead to an initially flourishing banking sector. In doing so, the paper elaborates on the economic oversights that were made during the financial build-up of the country and how such mistakes contributed to the crash. The focus is thus on identifying the main factors that contributed to the...

  9. Changes in soil test phosphorus and phosphorus in runoff from calcareous soils receiving manure, compost, and fertilizer application with and without alum

    Science.gov (United States)

    Intensification of the dairy industry in southern Idaho had led to the over-application of manures and a buildup of soil phosphorus (P) which is a potential threat to water quality in the region. As the use of alum has been shown to reduce both soluble manure P and runoff P from alum treated manure...

  10. A Topological Extension of General Relativity to Explore the Nature of Quantum Space-Time, Dark Energy and Inflation

    NARCIS (Netherlands)

    Spaans, M.

    2013-01-01

    General Relativity is extended into the quantum domain. A thought experiment is ex- plored to derive a specific topological build-up for Planckian space-time. The presented arguments are inspired by Feynman’s path integral for superposition andWheeler’s quan- tum foam of Planck mass mini black holes

  11. Residual Stress Induced by Nitriding and Nitrocarburizing

    DEFF Research Database (Denmark)

    Somers, Marcel A.J.

    2005-01-01

    The present chapter is devoted to the various mechanisms involved in the buildup and relief of residual stress in nitrided and nitrocarburized cases. The work presented is an overview of model studies on iron and iron-based alloys. Subdivision is made between the compound (or white) layer...

  12. Unlinked genetic loci control the reduced transcription of aminopeptidase N 1 and 3 in the European corn borer and determine tolerance to Bacillus thuringiensis Cry1Ab toxin

    Science.gov (United States)

    Crystalline (Cry) toxins from Bacillus thuringiensis (Bt) control insect feeding damage on crop plants via foliar applications or by expression within transgenic plants, but continued Bt use is threatened by the buildup of insect resistance traits. Aminopeptidase N (apn) gene family members encode m...

  13. 75 FR 10477 - Draft Report to Congress: Study of Discharges Incidental to Normal Operation of Commercial...

    Science.gov (United States)

    2010-03-08

    ...-disrupting compounds); and pathogen indicators (i.e., E. coli, enterococci, fecal coliforms). EPA found that... that leachate from antifouling hull coatings used on certain vessels to prevent buildup of organisms... water body. Using the results obtained in this study, EPA used a simple model to evaluate how the...

  14. Genetic radiation effects and natural radioactivity of human population in Brazil

    International Nuclear Information System (INIS)

    A study on areas of natural radioactivity is done, covering the genetic effects on human population. The study is done in depth dealing with aspecto such as radioactive area involved, discussion of materials and methods, errors and fallacies, influential factors, models, buildup and natural radioactivity, hypotheses, results and perspectives, etc. It covers 24 localites, 8.572 couples and 43.930 pregnancy cases

  15. Reconciling complexity with stability in naturally assembling food webs

    NARCIS (Netherlands)

    Neutel, Anje-Margriet; Heesterbeek, Johan A.P.; van de Koppel, Johan; Hoenderboom, Guido; Vos, An; Kaldeway, Coen; Berendse, Frank; Ruiter, Peter C. de

    2007-01-01

    Understanding how complex food webs assemble through time is fundamental both for ecological theory and for the development of sustainable strategies of ecosystem conservation and restoration. The build-up of complexity in communities is theoretically difficult, because in random-pattern models comp

  16. Photovoltaic Barometer - EurObserv'ER - April 2010

    International Nuclear Information System (INIS)

    The global photovoltaic market expanded again in 2009. Germany set a new system installation record while the capacity build-up of the major solar photovoltaic markets contained the fallout generated by the Iberian market derailment. The European Union has the highest photovoltaic plant capacity, with almost 5.5 GWp installed in 2009

  17. The Short Term Effects of Ditch Dredging to Nutrient Saturation onto Ditch Bed Materials

    Science.gov (United States)

    In the Midwestern United States, drainage ditches are an essential part of our landscape to ensure agriculture productivity. Sediment buildup reduces the flow rate of ditches and thus field tile lines, it then becomes necessary to dredge drainage ditches occasionally to optimize removal of water fr...

  18. Single-Bunch Instability Driven by the Electron Cloud Effect in the Positron Damping Ring of the International Linear Collider

    OpenAIRE

    Pivi, Mauro; Raubenheimer, Tor O.; Ghalam, Ali; Harkay, Katherine; Ohmi, Kazuhito; Wanzenberg, Rainer; Wolski, Andrzej; Zimmermann, Frank

    2005-01-01

    Collective instabilities caused by the formation of anelectron cloud (EC) are a potential limitation to the performances of the damping rings for a future linear collider. In this paper, we present recent simulation results for the electron cloud build-up in damping rings of different circumferences and discuss the single-bunch instabilities driven by the electron cloud.

  19. Adopt a Four-pronged Approach against Scientific Misconduct

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Scientific misconduct has become a social issue that should not be overlooked,warns CAS President LU Yongxiang. To cope with the problem, he emphasizes that it is far from sufficient to simply call for scientists to exercise self-discipline.Stress must be also placed on the enhancement of ethics education,social supervision and institutional buildup in the S&T community.

  20. Solar-Cell Slide Rule

    Science.gov (United States)

    Yamakawa, K. A.

    1983-01-01

    Slide rule relates efficiency, impurity types, impurity concentrations, and process types. Solar cell slide rule calculations are determination of allowable impurity concentration for nonredistributive process, determination of impurity buildup factor for redistributive process and determination of allowable impurity concentration for redistributive process.

  1. Population dynamics and life history strategies of the dominant copepods in a sub-arctic Greenlandic fjord

    DEFF Research Database (Denmark)

    Kjellerup, Sanne; Nielsen, Torkel Gissel

    production of two Calanus species and Metridia longa was monitored weekly from March-August. M. longa performed diel vertical migration of up to 200 meters and was the dominating larger copepod species. Weekly lipid measurements of M. longa showed a similar buildup of lipids during late summer as the 20...

  2. Cleansing orthodontic brackets with air-powder polishing: effects on frictional force and degree of debris

    Science.gov (United States)

    Leite, Brisa dos Santos; Fagundes, Nathalia Carolina Fernandes; Aragón, Mônica Lídia Castro; Dias, Carmen Gilda Barroso Tavares; Normando, David

    2016-01-01

    ABSTRACT Introduction: Debris buildup on the bracket-wire interface can influence friction. Cleansing brackets with air-powder polishing can affect this process. Objective: The aim of this study was to evaluate the frictional force and amount of debris remaining on orthodontic brackets subjected to prophylaxis with air-powder polishing. Methods: Frictional force and debris buildup on the surface of 28 premolar brackets were evaluated after orthodontic treatment. In one hemiarch, each bracket was subjected to air-powder polishing (n = 14) for five seconds, while the contralateral hemiarch (n = 14) served as control. Mechanical friction tests were performed and images of the polished bracket surfaces and control surfaces were examined. Wilcoxon test was applied for comparative analysis between hemiarches at p < 0.05. Results: Brackets that had been cleaned with air-powder polishing showed lower friction (median = 1.27 N) when compared to the control surfaces (median = 4.52 N) (p < 0.01). Image analysis showed that the control group exhibited greater debris buildup (median = 2.0) compared with the group that received prophylaxis with air-powder polishing (median = 0.5) (p < 0.05). Conclusion: Cleansing orthodontic brackets with air-powder polishing significantly reduces debris buildup on the bracket surface while decreasing friction levels observed during sliding mechanics. PMID:27653265

  3. Mechanisms of nutritional and hormonal regulation of lipogenesis

    NARCIS (Netherlands)

    Kersten, S.

    2001-01-01

    Fat build-up is determined by the balance between lipogenesis and lipolysis/fatty acid oxidation. In the past few years, our understanding of the nutritional, hormonal and particularly transcriptional regulation of lipogenesis has expanded greatly. Lipogenesis is stimulated by a high carbohydrate di

  4. Echolocation Reconsidered: Using Spatial Variations in the Ambient Sound Field To Guide Locomotion.

    Science.gov (United States)

    Ashmead, Daniel H.; Wall, Robert S.; Eaton, Susan B.; Ebinger, Kiara A.; Snook-Hill, Mary-Maureen; And Others

    1998-01-01

    Presents an acoustical model and evidence from four experiments that children with visual impairments use the buildup of low-frequency sound along walls to guide locomotion. The model differs from the concept of echolocation by emphasizing sound that is ambient, rather than self-produced, and of low frequency. (Author/CR)

  5. A Topological Extension of General Relativity to Explore the Nature of Quantum Spacetime, Dark Energy and Inflation

    NARCIS (Netherlands)

    Spaans, M.

    2013-01-01

    General Relativity is extended into the quantum domain. A thought experiment is explored to derive a specific topological build-up for Planckian spacetime. The presented arguments are inspired by Feynman's path integral for superposition and Wheeler's quantum foam of Planck mass mini black holes (BH

  6. Oil supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Babusiaux, D

    2004-07-01

    Following the military intervention in Iraq, it is taking longer than expected for Iraqi exports to make a comeback on the market. Demand is sustained by economic growth in China and in the United States. OPEC is modulating production to prevent inventory build-up. Prices have stayed high despite increased production by non-OPEC countries, especially Russia. (author)

  7. Numerical continuum mechanics

    CERN Document Server

    Kukudzhanov, Vladimir N

    2013-01-01

    This work focuses on computational methods in continuum thermomechanics. The text is based on the author's lectures, which ensures a didactical and coherent buildup.The main emphasis is put on the presentation of ideas and qualitative considerations, illustrated by specific examples and applications. Conditions and explanations that are essential for the practical application of methods are discussed thoroughly.

  8. Traumatic Brain Injury: Hope through Research

    Science.gov (United States)

    ... with CTE have abnormal microscopic deposits of a protein known as tau. Accumulations of tau are also found in the ... substance known as a ligand to bind to tau, which can then be detected using positron ... hygroma - a buildup of protein rich fluid in the area between the dura ...

  9. Experimental Determination and Numerical Modelling of Process Induced Strains and Residual Stresses in Thick Glass/Epoxy Laminate

    DEFF Research Database (Denmark)

    Nielsen, Michael Wenani; Hattel, Jesper Henri; Løgstrup Andersen, Tom;

    2012-01-01

    In this work, a cure hardening instantaneous linear elastic (CHILE) model and a path dependent (PD) constitutive approach are compared, for the case of modelling strain build-up during curing of a thick composite laminate part. The PD approach is a limiting case of viscoelasticity with path...

  10. Filtration of Nanoparticles: Evolution of Cake Structure and Pressure-Drop

    DEFF Research Database (Denmark)

    Elmøe, Tobias Dokkedal; Tricoli, Antonio; Grunwaldt, Jan-Dierk;

    2009-01-01

    with constant solid volume fraction began to form, accompanied with build-up of pressuredrop which was in excellent agreement with classic cake filtration theory. An expression for the solid volume fraction of the cake (fsd,c) was obtained as a sole function of Pe. In addition, the filtration efficiency became...

  11. Five years on. The status at Fukushima-Daiichi

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, David [NucNet, Brussels (Belgium)

    2016-05-15

    Since the March 2011 accident in Japan the authorities and the operator Tepco have been struggling to control the buildup of contaminated water and reduce levels of radiation. What has been done - and what's the work that still remains?.

  12. 77 FR 71561 - Health and Safety Data Reporting; Addition of Certain Chemicals

    Science.gov (United States)

    2012-12-03

    ... cadmium leads to a build-up of cadmium in the kidneys which can cause kidney disease. Cadmium has been.... Federal Register (41 FR 36902, September 1, 1976). 2. EPA. Integrated Risk Information System. Cadmium... . 3. Agency for Toxic Substances and Disease Registry (ATSDR), U.S. Department of Health and...

  13. Exact solutions to the Boltzmann equation by mapping the scattering integral into a differential operator

    Energy Technology Data Exchange (ETDEWEB)

    Zabadal, Jorge; Borges, Volnei; Van der Laan, Flavio T., E-mail: jorge.zabadal@ufrgs.br, E-mail: borges@ufrgs.br, E-mail: ftvdl@ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Departamento de Engenharia Mecanica. Grupo de Pesquisas Radiologicas; Ribeiro, Vinicius G., E-mail: vinicius_ribeiro@uniritter.edu.br [Centro Universitario Ritter dos Reis (UNIRITTER), Porto Alegre, RS (Brazil); Santos, Marcio G., E-mail: phd.marcio@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Tramandai, RS (Brazil). Departamento Interdisciplinar do Campus Litoral Norte

    2015-07-01

    This work presents a new analytical method for solving the Boltzmann equation. In this formulation, a linear differential operator is applied over the Boltzmann model, in order to produce a partial differential equation in which the scattering term is absent. This auxiliary equation is solved via reduction of order. The exact solution obtained is employed to define a precursor for the buildup factor. (author)

  14. In search of sharp fat contours

    NARCIS (Netherlands)

    Van de Graaf, A.

    2005-01-01

    A heart attack is usually caused by a build-up of fatty deposits in the coronary arteries. In many cases the patient will have noticed early warnings signs such as rapid exhaustion and shortness of breath. A cardiologist can now use an ultrasonic sensor to detect fatty deposits in the coronary arter

  15. Biobased chemicals from polyhydroxybutyrate

    NARCIS (Netherlands)

    Spekreijse, Jurjen

    2016-01-01

    Currently, most chemicals and materials are obtained from fossil resources. After use, these chemicals and materials are converted to CO2. As discussed in chapter 1, this causes a build-up of CO2 in the atmosphere, the main driving force of global warming. In order to reach a sustai

  16. Catalytic Converters Maintain Air Quality in Mines

    Science.gov (United States)

    2014-01-01

    At Langley Research Center, engineers developed a tin-oxide based washcoat to prevent oxygen buildup in carbon dioxide lasers used to detect wind shears. Airflow Catalyst Systems Inc. of Rochester, New York, licensed the technology and then adapted the washcoat for use as a catalytic converter to treat the exhaust from diesel mining equipment.

  17. Molecular comparisons for identification of food spoilage yeasts and prediction of species that may develop in different food products

    Science.gov (United States)

    Spoilage of foods and beverages by yeasts is often characterized by objectionable odors, appearance, taste, texture or build-up of gas in packaging containers, resulting in loss of the product. Seldom is human health compromised by products spoiled by yeasts even though some spoilage is caused by sp...

  18. An Ambiguity

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Energy is of strategic importance to sus- tainable development. None of the world’s major energy-consuming economies can af- ford to give up regulating the energy market This regulation consists of price controls, buildup of state reserves and monopolized sales. From this perspective, the Chinese Government’s existing energy policy based

  19. On the normal stress effect in grease-lubricated bearing seals

    NARCIS (Netherlands)

    Baart, P.; Lugt, P.M.; Prakash, B.

    2014-01-01

    The film formation in lip seals, due to the non-Newtonian rheology of the lubricant, has been a topic of speculation. Earlier work suggests that normal stresses in grease would be favorable for the film buildup between the seal lip and shaft or bearing ring. In the current article, we evaluate this

  20. Cyclone separator having boundary layer turbulence control

    Science.gov (United States)

    Krishna, Coimbatore R.; Milau, Julius S.

    1985-01-01

    A cyclone separator including boundary layer turbulence control that is operable to prevent undue build-up of particulate material at selected critical areas on the separator walls, by selectively varying the fluid pressure at those areas to maintain the momentum of the vortex, thereby preventing particulate material from inducing turbulence in the boundary layer of the vortical fluid flow through the separator.

  1. Bacteriological Survey of AFD (Meat Packing Plant

    Directory of Open Access Journals (Sweden)

    T. N. Rawal

    1974-04-01

    Full Text Available The paper describes the manufacturing process of freeze dried mutton from slaughtering to packing and makes an assessment of microbial build-up on equipment, hands of workers and environment in which the mutton comes in contact during processing.

  2. Absolute phase control of spectra effects in a two-level medium driven by two-color ultrashort laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Xia Keyu [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Sciences (China); Niu Yueping [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Sciences (China); Li Chunfang [Department of Physics, Shanghai University, Shanghai 200436 (China); Gong Shangqing [CCAST (World Laboratory), PO Box 8730, Beijing 100080 (China) and State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)]. E-mail: sqgong@siom.ac.cn

    2007-01-22

    Using a {omega}-3{omega} combination scenario, we investigate the absolute phase control of the spectra effects for ultrashort laser pulses propagating in a two-level medium. It is found that the higher spectral components can be controlled by the absolute phases. In particular, different absolute phase combinations can lead to the buildup or split of the even harmonics.

  3. Critical Review of Membrane Bioreactor Models

    DEFF Research Database (Denmark)

    Naessens, W.; Maere, T.; Ratkovich, Nicolas Rios;

    2012-01-01

    Membrane bioreactor technology exists for a couple of decades, but has not yet overwhelmed the market due to some serious drawbacks of which operational cost due to fouling is the major contributor. Knowledge buildup and optimisation for such complex systems can heavily benefit from mathematical...

  4. Failure Analysis and Thermochemical Surface Engineering of Bearings in the Wind Turbine Drivetrain

    DEFF Research Database (Denmark)

    West, Ole H.E.; Dahl, Kristian Vinter; Christiansen, Thomas Lundin

    increase of WEA formation with each cycle was suggested. By X-ray diffraction stress analysis the nonuniform build-up of compressive stresses under testing was identified. Deep nitriding is considered as a potential remedy against WEC failure. Therefore nitriding experiments were conducted to study...

  5. Evaluation of efficacy of restorative dental treatment provided under general anesthesia at hospitalized pediatric dental patients of Isfahan

    Directory of Open Access Journals (Sweden)

    Alireza Eshghi

    2012-01-01

    Conclusion: Stainless steel crown restorations had significantly better results vs other posterior restorations. The failure rates of stainless steel crown and anterior composite resin build-up restorations did not correlate with the time of follow-up in comparison of other restorations.

  6. AIR RADIOACTIVITY MONITOR

    Science.gov (United States)

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  7. Dynamic Desynchronization of a Free-Electron Laser Resonator

    NARCIS (Netherlands)

    Bakker, R. J.; Knippels, G.M.H.; van der Meer, A. F. G.; Oepts, D.; Jaroszynski, D. A.; van Amersfoort, P. W.

    1993-01-01

    In a free-electron laser oscillator operating with short electron bunches, the desynchronism between electron bunches and optical pulses resulting in the shortest buildup time to saturation is different from that giving the largest saturated power. In this Rapid Communication we present an experimen

  8. Cash Constraints and Credit Corsets : The Chimera of Interenterprise Credit

    OpenAIRE

    Condon, Timothy; S. Ramachandran

    1995-01-01

    The buildup of interenterprise credit in many Central and Eastern European countries is often seen as a problem that requires a government bailout. The authors show that arrears rise only temporarily, as the hard budget constraint bites, and then plateau. Therefore, they argue that while governments should monitor the stock of debt to see how quickly enterprises are adjusting, they shouldn...

  9. Silicon nanowire field-effect chemical sensor

    NARCIS (Netherlands)

    Chen, Songyue

    2011-01-01

    This thesis describes the work that has been done on the project “Design and optimization of silicon nanowire for chemical sensing”, including Si-NW fabrication, electrical/electrochemical modeling, the application as ISFET, and the build-up of Si- NW/LOC system for automatic sample delivery. A nove

  10. How to Avoid a Darkening Debt Storm in the Caribbean

    DEFF Research Database (Denmark)

    Hallett, Andrew Hughes; Hougaard Jensen, Svend E.

    2015-01-01

    growth. Specifically, we stress the need to prevent a build-up of debt, public and private, by introducing a mechanism to ensure that public and private borrowing is consistent with an overall macroeconomic strategy. This introduces elements of a banking union framework, tied into Europe's notion...

  11. How to Avoid a Darkening Debt Storm in the Caribbean

    DEFF Research Database (Denmark)

    Hallett, Andrew Hughes; Hougaard Jensen, Svend E.

    growth. Specifically, we stress the need to prevent a build-up of debt, public and private, by introducing a mechanism to ensure that public and private borrowing is consistent with an overall macroeconomic strategy. This introduces elements of a banking union framework, tied into Europe‟s notion...

  12. Trapping effects and acoustoelectric current saturation in ZnO single crystals

    DEFF Research Database (Denmark)

    Mosekilde, Erik

    1970-01-01

    Measurements of current-voltage characteristics for ZnO single crystals at temperatures between 77 and 640 °K are reported. Because of the buildup of an intense acoustic flux, a strong current saturation sets in when the trap-controlled electron drift velocity is equal to the velocity of sound...

  13. CATEGORIAS ESENCIALES PARA COMPRENDER LA EXISTENCIA DEL SER HUMANO Y SUS TRANSFORMACIONES EN LA PSICOLOGIA HUMANISTA EXISTENCIAL

    Directory of Open Access Journals (Sweden)

    Clara Ines Vega Palacio

    2010-06-01

    Full Text Available The current article appears as an intent to buildup a conceptual, punctual, and deep reflectionin the exercise of an enlightening thought aboutthe human being and his transformations, whatthe Humanistic-Existential psychology considersto be the principles to understand existence;four essential categories are approached beingthe capital elements for the research in theContemporary Transformations group.

  14. Experimental Validation of a Mathematical Model for Seabed Liquefaction Under Waves

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Kirca, Özgür; Fredsøe, Jørgen

    2012-01-01

    This paper summarizes the results of an experimental study directed towards the validation of a mathematical model for the buildup of pore water pressure and resulting liquefaction of marine soils under progressive waves. Experiments were conducted under controlled conditions with silt (d(50) = 0...

  15. De invloed van bebouwing en vegetatie op luchtkwaliteit. Scanning en scouting lucht

    NARCIS (Netherlands)

    Bloemen HJT; Uiterwijk W; Putten E van; Wesseling J; LVM

    2007-01-01

    The impact on air quality of build-up and vegetation near highways appears to be limited and in same cases rather complex. Buildings and vegetation will have an impact on air quality in the direct surroundings. In case of exceedences of the EU directives the scale of this impact is of interest for

  16. 9 CFR 318.305 - Equipment and procedures for heat processing systems.

    Science.gov (United States)

    2010-01-01

    ... processing systems. 318.305 Section 318.305 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE... temperature device, the recording accuracy shall be equal to or better than 1F °(or 0.5C°) at the process... and replenished with potable water to prevent the buildup of organic matter and other materials....

  17. 9 CFR 381.305 - Equipment and procedures for heat processing systems.

    Science.gov (United States)

    2010-01-01

    ... processing systems. 381.305 Section 381.305 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE... accuracy shall be equal to or better than 1 °F (or 0.5 °C) at the process temperature. The temperature... to prevent the buildup of organic matter and other materials. (3) Container cooling waters that...

  18. Impact of slow-light enhancement on optical propagation in active semiconductor photonic crystal waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; de Lasson, Jakob Rosenkrantz; Gregersen, Niels;

    2015-01-01

    , the realization of short optical amplifiers compatible with photonic integration. The coupled wave analysis is compared to numerical approaches based on the Fourier modal method and a frequency domain finite element technique. The presence of material gain leads to the build-up of a backscattered field, which...

  19. Discontinuity effects in dynamically loaded tilting pad journal bearings

    DEFF Research Database (Denmark)

    Thomsen, Kim; Klit, Peder; Vølund, Anders

    2011-01-01

    This paper describes two discontinuity effects that can occur when modelling radial tilting pad bearings subjected to high dynamic loads. The first effect to be treated is a pressure build-up discontinuity effect. The second effect is a contact-related discontinuity that disappears when a contact...

  20. Effects of bedding material on ammonia volatilization in a broiler house

    Science.gov (United States)

    Ammonia volatilization from poultry house bedding material is a major production issues because the buildup of ammonia within the facilities is a human health issue and can negatively impact the performance of the birds. Major operational cost is associated with the ventilation of poultry houses to ...

  1. LEAF: a computer program to calculate fission product release from a reactor containment building for arbitrary radioactive decay chains

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.E.; Apperson, C.E. Jr.; Foley, J.E.

    1976-10-01

    The report describes an analytic containment building model that is used for calculating the leakage into the environment of each isotope of an arbitrary radioactive decay chain. The model accounts for the source, the buildup, the decay, the cleanup, and the leakage of isotopes that are gas-borne inside the containment building.

  2. Intumescent coatings under fast heating

    DEFF Research Database (Denmark)

    Nørgaard, Kristian Petersen; Dam-Johansen, Kim; Català, Pere;

    2012-01-01

    Intumescent coatings are widely used to delay or minimise the destructive effects of fire. They are usually tested under conditions that simulate the relatively slow build-up of heat in a normal fire. Here, the effects of damage during a fire causing sudden heating of the coating were studied....

  3. Aged forests could still act as carbon sinks

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Old-growth forests are traditionally negligible as carbon sinks, but CAS scientists recently reported that the buildup of atmospheric carbon in the top-soils of 400-year-old forests in southern China has increased at an unexpectedly high rate up to nearly 68% from 1979 to 2003.

  4. Hammertoe

    Science.gov (United States)

    ... are inherited. Symptoms Common symptoms of hammertoes include: Pain or irritation of the affected toe when wearing shoes. Corns and calluses (a buildup of skin) on the toe, between two toes or on the ball of the foot. Corns are caused by constant friction against the ...

  5. John Hardy is the UK's first Breakthrough Prize laureate.

    Science.gov (United States)

    Martin, Seamus J

    2015-12-01

    John Hardy, Professor of Neuroscience at University College London and Editorial Board member of The FEBS Journal, has been awarded The Breakthrough Prize in Life Sciences in recognition of his work identifying mutations that cause amyloid build-up in the brain--research that has transformed the study of Alzheimer's disease and other major neurodegenerative diseases.

  6. ENGINEERING AND ECONOMIC EVALUATION OF GAS RECOVERY AND UTILIZATION TECHNOLOGIES AT SELECTED U.S. MINES

    Science.gov (United States)

    Methane liberated in underground coal mines is a severe safety hazard to miners. It is also a major contributor to the build-up of greenhouse gases in the global atmosphere. This report presents an engineering and economic evaluation of several methane recovery and end-use techno...

  7. Oil supply and demand

    International Nuclear Information System (INIS)

    Following the military intervention in Iraq, it is taking longer than expected for Iraqi exports to make a comeback on the market. Demand is sustained by economic growth in China and in the United States. OPEC is modulating production to prevent inventory build-up. Prices have stayed high despite increased production by non-OPEC countries, especially Russia. (author)

  8. A New Connection Between Greenhouse Warming and Stratospheric Ozone Depletion

    Science.gov (United States)

    Salawitch, R.

    1998-01-01

    The direct radiative effects of the build-up of carbon dioxide and other greenhouse gases have led to a gradual cooling of the stratosphere with largest changes in temperature occurring in the upper stratosphere, well above the region of peak ozone concentration.

  9. Adaptation Reveals Multiple Levels of Representation in Auditory Stream Segregation

    Science.gov (United States)

    Snyder, Joel S.; Carter, Olivia L.; Hannon, Erin E.; Alain, Claude

    2009-01-01

    When presented with alternating low and high tones, listeners are more likely to perceive 2 separate streams of tones ("streaming") than a single coherent stream when the frequency separation ([delta]f) between tones is greater and the number of tone presentations is greater ("buildup"). However, the same large-[delta]f sequence reduces streaming…

  10. Hydraulic testing of Salado Formation evaporites at the Waste Isolation Pilot Plant site: Second interpretive report

    Energy Technology Data Exchange (ETDEWEB)

    Beauheim, R.L. [Sandia National Labs., Albuquerque, NM (United States); Roberts, R.M.; Dale, T.F.; Fort, M.D.; Stensrud, W.A. [INTERA, Inc., Austin, TX (United States)

    1993-12-01

    Pressure-pulse, constant-pressure flow, and pressure-buildup tests have been performed in bedded evaporites of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) site to evaluate the hydraulic properties controlling brine flow through the Salado. Transmissivities have been interpreted from six sequences of tests conducted on five stratigraphic intervals within 15 m of the WIPP underground excavations.

  11. Sedimented, hybrid and multiple? The new cultural geography of identities

    Directory of Open Access Journals (Sweden)

    Joseph Straubhaar

    2013-06-01

    Full Text Available This paper explores the sedimentation of multiple levels of media use and identity as a key element of the changing cultural geography of globalization. In this paper, we examine the relationship between processes of hybridization of identity and culture over time and the sedimentation or buildup, maintenance, and defense of multilayered identities.

  12. Does a coupling capacitor enhance the charge balance during neural stimulation? An empirical study

    NARCIS (Netherlands)

    Van Dongen, M.N.; Serdijn, W.A.

    2015-01-01

    Due to their DC-blocking characteristic, coupling capacitors are widely used to prevent potentially harmful charge buildup at the electrode–tissue interface. Although the capacitors can be an effective safety measure, it often seems overlooked that coupling capacitors actually introduce an offset vo

  13. All Charged Up!--Experimenting with Static Electricity

    Science.gov (United States)

    Roman, Harry T.

    2011-01-01

    Build-up of static electricity happens readily when the air is cold and dry and is a common part of life. There are lots of ways to make students aware of static electricity--and many things one can teach them about its applications in today's industry. In this article, the author describes examples and experiments that will bring static…

  14. 49 CFR 178.277 - Requirements for the design, construction, inspection and testing of portable tanks intended for...

    Science.gov (United States)

    2010-10-01

    ... construction requirements. (1) Portable tanks must be of seamless or welded steel construction and have a water... vapor side of the pressure build-up coil. (6) The materials of construction of valves and accessories... 49 Transportation 2 2010-10-01 2010-10-01 false Requirements for the design,...

  15. John Hardy is the UK's first Breakthrough Prize laureate.

    Science.gov (United States)

    Martin, Seamus J

    2015-12-01

    John Hardy, Professor of Neuroscience at University College London and Editorial Board member of The FEBS Journal, has been awarded The Breakthrough Prize in Life Sciences in recognition of his work identifying mutations that cause amyloid build-up in the brain--research that has transformed the study of Alzheimer's disease and other major neurodegenerative diseases. PMID:26573785

  16. Pulse-To-Pulse Spectra of a Picosecond Optical Parametric Oscillator Based on Chirped Quasi-Phase Matching

    OpenAIRE

    Descloux, D.; Laporte, C.; Dherbecourt, J.B.; Melkonian, J.M.; Raybaut, M.; Drag, C.; Godard, A.

    2014-01-01

    The pulse-to-pulse evolution of the spectrum emitted by a picoseconds synchronously-pumped optical parametric oscillator based on chirped quasi-phase matching is measured, enabling to study the spectro-temporal dynamics upon the buildup of the oscillation.

  17. Guided wave sensing of polyelectrolyte multilayers

    DEFF Research Database (Denmark)

    Horvath, R.; Pedersen, H.C.; Cuisinier, F.J.G.

    2006-01-01

    A planar optical waveguide configuration is proposed to monitor the buildup of thick polyelectrolyte multilayers on the surface of the waveguide in aqueous solutions. Instead of detecting the layer by the electromagnetic evanescent field the polyelectrolyte layer acts as an additional waveguiding...

  18. Southeastern USA regional landscape patterns and population dynamics of the stink bug, Euchistus servus

    Science.gov (United States)

    Introduction: The brown stink bug, Euschistus servus is an economically important pest of many agronomic crops in the southern USA, motivating the study of factors influencing population build-up in agricultural regions and landscapes to facilitate management. Methods: ArcGIS was used to characteriz...

  19. Lance for injecting highly-loaded coal slurries into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Illuminati, D.

    1991-10-29

    A lance is used to inject fuel oil into a blast furnace. This simple design permits conversion of coal water and coal tar slurries to a fine mist at very low flow rates. This design prevents the build-up of deposits which increases service life and steadies the flow rate.

  20. Asymmetric membrane structures as a result of phase separation phenomena

    NARCIS (Netherlands)

    Broens, L.; Altena, F.W.; Smolders, C.A.; Koenhen, D.M.

    1980-01-01

    In this report we give a description of the membrane formation mechanism based on theoretical and experimental knowledge of phase separation phenomena in concentrated polymer solutions. We demonstrate that different types of phase separation are responsible for the build-up of the dense skin layer a

  1. Enabling laser applications in microelectronics manufacturing

    Science.gov (United States)

    Delmdahl, Ralph; Brune, Jan; Fechner, Burkhard; Senczuk, Rolf

    2016-02-01

    In this experimental study, we report on high-pulse-energy excimer laser drilling into high-performance build-up films which are pivotal in microelectronics manufacturing. Build-up materials ABF-GX13 from Ajinomoto as well as ZS-100 from Zeon Corporation are evaluated with respect to their viability for economic excimer laser-based micro-via formation. Excimer laser mask imaging projection at laser wavelengths of 193, 248 and 308 nm is employed to generate matrices of smaller micro-vias with different diameters and via pitches. High drilling quality is achievable for all excimer laser wavelengths with the fastest ablation rates measured in the case of 248 and 308 nm wavelengths. The presence of glass fillers in build-up films as in the ABF-GX13 material poses some limitations to the minimum achievable via diameter. However, surprisingly good drilling results are obtainable as long as the filler dimensions are well below the diameter of the micro-vias. Sidewall angles of vias are controllable by adjusting the laser energy density and pulse number. In this work, the structuring capabilities of excimer lasers in build-up films as to taper angle variations, attainable via diameters, edge-stop behavior and ablation rates will be elucidated.

  2. LEAF: a computer program to calculate fission product release from a reactor containment building for arbitrary radioactive decay chains

    International Nuclear Information System (INIS)

    The report describes an analytic containment building model that is used for calculating the leakage into the environment of each isotope of an arbitrary radioactive decay chain. The model accounts for the source, the buildup, the decay, the cleanup, and the leakage of isotopes that are gas-borne inside the containment building

  3. Indonesia : Public Spending in a Time of Change

    OpenAIRE

    World Bank

    2000-01-01

    The study identifies strategic priorities for restoring sound public finances, emphasizing the need to maintain fiscal sustainability, under a constrained budget, and the need to improve the processes for making budgetary allocations, and budget implementation, towards greater fiscal transparency. It reviews Indonesia's public spending during the crisis, and the unavoidable build-up of fis...

  4. Phosphorus movement and speciation in a sandy soil profile after long-term animal manure applications

    NARCIS (Netherlands)

    Koopmans, G.F.; Chardon, W.J.; McDowell, R.W.

    2007-01-01

    Long-term application of phosphorus (P) with animal manure in amounts exceeding removal with crops leads to buildup of P in soil and to increasing risk of P loss to surface water and eutrophication. In most manures, the majority of P is held within inorganic forms, but in soil leachates organic P fo

  5. Ears and Altitude

    Science.gov (United States)

    ... the middle ear pressure cannot be equalized. The air already there is absorbed and a vacuum occurs, sucking the eardrum ... a pressure buildup but do not let the air out your mouth The ears have been ... of a physician who has experience in the care of ear disorders. The ear ...

  6. Carbon cycling in the northern Arabian Sea during the northeast monsoon: Significance of salps

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Sarma, V.V.S.S.; Jayakumar, D.A.

    for filter feeders that can efficiently utilize abundant smaller plankton. This may lead to periodic removal of chlorophyll, thereby moderating primary production as well as episodic build-up of DOC in the upper layers. This DOC pool may be used as a nutrient...

  7. The effects of updating ability and knowledge of reading strategies on reading comprehesion

    NARCIS (Netherlands)

    M.M.L. Muijselaar; P.F. de Jong

    2015-01-01

    Updating ability and reading strategies are considered as important factors in the buildup of a mental model of a text. However, only few studies examined the relation of updating and knowledge of reading strategies with reading comprehension. The aim of the current study was to investigate the spec

  8. A derivation of the Derbenev-Kondratenko formula using semi-classical electrodynamics

    International Nuclear Information System (INIS)

    We present a detailed exposition of the mechanism for the build-up of polarization in electron storage rings. A semi-classical approach is used to derive the rate of growth and asymptotic degree of polarization in an electron storage ring (the Derbenev-Kondratenko formula). Statistical mechanical concepts used to obtain as classical an understanding as possible of this phenomenon. (orig.)

  9. Coronary Angioplasty Stent Placement

    Medline Plus

    Full Text Available ... and years to develop. It’s a buildup of cholesterol plaque within the arterial wall that occludes the ... we call “hyperlipidemia” or “dislipidemia,” or commonly, high cholesterol, and we look at the fractions with the ...

  10. Reliability Based assessment of buildings under earthquakes due to gas extraction

    NARCIS (Netherlands)

    Steenbergen, R.D.J.M.; Vrouwenvelder, A.C.W.M.

    2014-01-01

    In the northern part of the Netherlands over de last decades shallow earthquakes are induced due to large scale gas extraction from the Groningen gas field. Earthquakes occur due to the compaction of the reservoir rock, which leads to subsidence at surface and strain build-up in the reservoir rock a

  11. Optimisation potential of sucker rod deep drilling systems in petroleum production at Brown Fields; Optimierungspotential von Gestaengetiefpumpensystemen bei der Erdoelfoerderung von Brown Fields

    Energy Technology Data Exchange (ETDEWEB)

    Sam, G.; Kass, M.; Rice, D. [Rohoel-Aufsuchungs AG (RAG), Gampern (Austria)

    2007-09-13

    Optimised operation of sucker rod deep drilling systems is a decisive criterion for economically efficient production from older wells with liquid build-up (Brown Fields). Possibilities for optimising the system as a whole are reviewed from different angles (software, hardware). Design software, design methods, material problems, and corrosion prevention are gone into. (orig.)

  12. The Potential for Low-Cost Concentrating Solar Power Systems

    International Nuclear Information System (INIS)

    Concern over the possibility of global climate change as a result of anthropogenic greenhouse gas buildup in the atmosphere is resulting in increased interest in renewable energy technologies. The World Bank recently sponsored a study to determine whether solar thermal power plants can achieve cost parity with conventional power plants. The paper reviews the conclusions of that study

  13. Computer simulation of multiple dynamic photorefractive gratings

    DEFF Research Database (Denmark)

    Buchhave, Preben

    1998-01-01

    The benefits of a direct visualization of space-charge grating buildup are described. The visualization is carried out by a simple repetitive computer program, which simulates the basic processes in the band-transport model and displays the result graphically or in the form of numerical data. The...

  14. Optical control of antibacterial activity

    NARCIS (Netherlands)

    Velema, Willem A.; van der Berg, Jan Pieter; Hansen, Mickel J.; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.

    2013-01-01

    Bacterial resistance is a major problem in the modern world, stemming in part from the build-up of antibiotics in the environment. Novel molecular approaches that enable an externally triggered increase in antibiotic activity with high spatiotemporal resolution and auto-inactivation are highly desir

  15. Soviet-American Relations: Cold War to New Thinking. Topic #5 in a Series of International Security and Conflict [Curricula] for Grades 9-12 and Community College.

    Science.gov (United States)

    Chan, Adrian

    This 12-day unit is designed for use in the social studies classroom for grades 9-12 and community college level. Students first learn about the ideological, political, and military rivalries of the United States and the Soviet Union that marked the Cold War. They are then introduced to the nuclear build-up, and they study its impact on matters of…

  16. The Origins of the Cold War.

    Science.gov (United States)

    Paterson, Thomas G.

    1986-01-01

    Briefly reviews conventional reasoning about the start of the Cold War. Describes contemporary revisionist views of the Cold War and the reasons they arose. Maintains that American leaders exaggerated the Soviet ideological and military threat, spurring an American arms build-up which ultimately led to the present-day arms race. (JDH)

  17. 75 FR 3859 - Safety Zone; Baltimore Captain of Port Zone

    Science.gov (United States)

    2010-01-25

    ..., 2008 issue of the Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public.... Heavy ice buildups can occur in the C & D Canal, from Town Point Wharf to Reedy Point. Other areas that... there is little vessel traffic associated with recreational boating and commercial fishing during...

  18. Developments in strategic landscape monitoring for the Nordic countries

    DEFF Research Database (Denmark)

    Landscape plays an increasingly relevant and prominent role in the protection and mangement of the Earth's terrestrial environments and ecosystems, including the diverse forested, agricultural, wilderness and build-up landscapes within the Nordic countries. However to be meaningful in the Informa...

  19. On the Presentation of Wave Phenomena of Electrons with the Young-Feynman Experiment

    Science.gov (United States)

    Matteucci, Giorgio

    2011-01-01

    The Young-Feynman two-hole interferometer is widely used to present electron wave-particle duality and, in particular, the buildup of interference fringes with single electrons. The teaching approach consists of two steps: (i) electrons come through only one hole but diffraction effects are disregarded and (ii) electrons come through both holes…

  20. An examination of the role of colonial Phaeocystis antarctica in the microbial food web of the Ross Sea

    Science.gov (United States)

    The extensive buildup of phytoplankton biomass in the Ross Sea conflicts with the view that high rates of herbivory occur in all regions of the Southern Ocean. Nano- and microplanktonic consumers comprise a significant fraction of total plankton biomass; however, the importance o...