WorldWideScience
1

Extended radio emission in MOJAVE Blazars: Challenges to Unification  

CERN Document Server

We present the results of a study on the 1.4 GHz kpc-scale radio emission in the complete flux density limited MOJAVE sample, comprising 135 radio-loud AGNs. While extended emission is detected in the majority of the sources, about 7% of the sources exhibit only radio core emission. Many BL Lacs exhibit extended radio power and kpc-scale morphology typical of powerful FRII jets, while a substantial number of quasars possess radio powers intermediate between FRIs and FRIIs. This poses challenges to the simple radio-loud unified scheme, which links BL Lacs to FRIs and quasars to FRIIs. We find a significant correlation between extended radio emission and pc-scale jet speeds: the more radio powerful sources possess faster jets. This indicates that the 1.4 GHz (or low frequency) radio emission is indeed related to jet kinetic power. Various properties such as extended radio power and ...

2010-01-01

3

Numerical study of inflow conditions on a turbulent isothermal or heated plane jet; Etude numerique des conditions d'emission sur un ecoulement de type jet plan turbulent isotherme ou chauffe  

Energy Technology Data Exchange (ETDEWEB)

We intend to solve equations governing turbulent plane-vertical isotherm and non isotherm jets by taking into account inflow conditions at the exit of the nozzle. The analysis is focused on the influence of these conditions on this type of flow. Two cases are considered (uniform and parabolic velocity and temperature profiles). A finite difference scheme is developed to solve the governing equations. This numeric model allows us to show that the region of fully developed regime begins much nearer the nozzle for the turbulent case than for the laminar flow case. Indeed, the turbulence increases the mixing between the incoming gas from the nozzle and the ambient fluid, and consequently the size of the potential core zone decreases. The results are compared to other works introducing mathematical variables based on the energy conservation for the case of the mixed convection and the momentum conservation for the forced convection, which allows the ...

1999-11-01

4

Study of the thermal plasma etching at atmospheric pressure on silica rods  

International Nuclear Information System (INIS)

Etching of SiO_2 rods has been obtained with a dc torch with argon as the process gas in an air environment at atmospheric pressure; the high temperature of the plasma jet causes vaporization of the exposed area. The apparatus and torch operative parameters have been set up to obtain a depth etch rate of up to 0.6 mm min"-"1 corresponding to 0.826 g min"-"1. An enthalpy probe has been employed to monitor the plasma conditions before the thermal plasma etching process and from the experimental etch rate a surface rod temperature of T_s_u_r = 2057 K has been derived. Etching has been obtained with uniformity over the entire exposed area with peak to peak differences below 1%. The plasma to rod heat transfer has been simulated using a commercial CFD code Fluent (copyright). The model consists of a non-steady two-dimensional simulation for a compressible turbulent fluid, with an adapted grid calculation. Boundary conditions have been set out using the enthalpy probe ...

2004-04-21

5

Sensitivity-based optimal capacitor placement on a radial distribution feeder  

Energy Technology Data Exchange (ETDEWEB)

Optimal capacitor placement determines the size, type, and location of capacitors to be installed on a radial distribution feeder that will reduce peak power and energy losses while minimizing the costs of investment and installation of the capacitor banks. This paper describes a sensitivity-based optimal placement of capacitors that employs a new load characterization scheme using a voltage-current-angle-logger. The proposed method allows modeling of loads of different power factors for different portions of the distribution feeder. The optimal solution is obtained by testing various combinations of capacitor banks (based on the smallest bank size specified by the user) and candidate nodes along the distribution feeder, and calculating the resultant savings. In order to reduce solution time, the candidate nodes are ranked according to their sensitivity factors. The highest ranking nodes are considered first in the ...

1995-12-31

6

Electron and ion beam effects in amorphous SiO_2 and Si_3N_4 films for electronic devices  

International Nuclear Information System (INIS)

The effect of electron and ion beam irradiation on the Sisub(LVV) Auger spectra of SiO_2, Si_3N_4 and Si-oxynitride films was measured by the relative intensity of the 92 eV signal, characteristic for the formation of 'free' silicon during irradiation. While in Si-oxynitride the beam effects were almost negligible, some damage was found in Si_3N_4, but SiO_2 appeared to be extremely sensitive for electron and ion beam irradiation. By low energy electron loss spectroscopy of ion bombarded SiO_2 and Si_3N_4 films new electron states due to broken Si-O and Si-N bonds could be determined within the band gap of the insulators. The measured energy losses were interpreted by means of electron energy level schemes of the amorphous films. (author).

1982-01-01

7

Electron and ion beam effects in amorphous SiO/sub 2/ and Si/sub 3/N/sub 4/ films for electronic devices  

Energy Technology Data Exchange (ETDEWEB)

The effect of electron and ion beam irradiation on the Sisub(LVV) Auger spectra of SiO/sub 2/, Si/sub 3/N/sub 4/ and Si-oxynitride films was measured by the relative intensity of the 92 eV signal, characteristic for the formation of 'free' silicon during irradiation. While in Si-oxynitride the beam effects were almost negligible, some damage was found in Si/sub 3/N/sub 4/, but SiO/sub 2/ appeared to be extremely sensitive for electron and ion beam irradiation. By low energy electron loss spectroscopy of ion bombarded SiO/sub 2/ and Si/sub 3/N/sub 4/ films new electron states due to broken Si-O and Si-N bonds could be determined within the band gap of the insulators. The measured energy losses were interpreted by means of electron energy level schemes of the amorphous films.

1982-10-01

8

Cumulative Jets Interaction with Spent Nuclear Fuel  

International Science & Technology Center (ISTC)

Research of Cumulative Jets Interaction with Spent Nuclear Fuel

9

Numerical study of the impingement of a supersonic, axisymmetric jet on a flat plate  

International Nuclear Information System (INIS)

A numerical method for studying the flow field of an under-expanded axis-symmetric jet created by a converging-diverging nozzle and impinging on a flat plate is presented. The calculation domain of interest is a region that contains all the features of the jet that leaves the nozzle and impinges onto the plate. Axial symmetry of the domain allows a reduced 2-dimensional model to be used. FLUENT software is utilized to solve the continuity, momentum and energy equations using a coupled implicit scheme. The ideal-gas law is used to determine the gas density along with a k-#epsilon# turbulence model with a special modification to account for compressibility effects. In addition, the temperature dependency of viscosity has been taken into consideration. A number of different modeling techniques are investigated including different approximations to account for the flow inside the nozzle. Performance of non-equilibrium wall ...

10

The oxidation of n-butylbenzene: Experimental study in a JSR at 10atm and detailed chemical kinetic modeling  

British Library Electronic Table of Contents (United Kingdom)

The oxidation of n-butylbenzene was studied in a jet-stirred reactor (JSR) at 10atm in dilute conditions providing new experimental results over the low- and high-temperature range 550-1180K, and variable equivalence ratio (0.25ϕ1.5). They consisted of concentration profiles of the reactants, stable intermediates and final products, measured as a function of temperature, at a constant residence time of 1s, by sonic probe sampling followed by on-line GC-MS and off-line GC-TCD-FID and GC-MS analyses. The oxidation of n-butylbenzene in these conditions was modeled using a detailed chemical kinetic reaction mechanism (404 species and 2210 reactions, most of them reversible) deriving from a previous scheme proposed for the ignition, oxidation, and combustion of simple aromatics (benzene,...

2011-01-01

15

The effects of organosulfur compounds upon the storage stability of Jet A fuel  

Science.gov (United States)

This study examined the effect of sulfur-containing compounds on the storage stability of Jet A

1981-01-01

16

The Behavior of Water in Jet Fuels and the Clogging of ...  

Science.gov (United States)

... values and unless special precautions and equipment are used, it would be very difficult to service and maintain operational jet-fuel systems with ...

1950-01-11

17

Mais Tallinna-Helsingi laevaliinile Nordic Jet Line / Koit Luus  

Index Scriptorium Estoniae

AS Nordic Jet Line uus katamaraan Tallinna-Helsingi laevaliinil

1998-01-01

18

Fuel retention in H mode experiments in JET  

International Nuclear Information System (INIS)

... edge localized modes h-mode plasma confinement jet tokamak l-mode plasma

2007-07-02

19

Range and energy loss rate of 118 MeV "2"8Si in some polymers  

International Nuclear Information System (INIS)

In the present work, range and energy loss rate of "2"8Si in four dielectric track detectors viz: Makrofol-KG (MFKG), Makrofol-G (MFG), Triafol-BN (TBN) and LR-115 (cellulose nitrate) have been measured. To calculate these parameters, a curve fitting method was proved to be very useful and easier with more accuracy. (author)

1999-01-01

20

Theoretical study on device efficiency of pulsed liquid jet pump  

International Nuclear Information System (INIS)

The influence of the main factors on device efficiency of pulsed liquid jet pump with gas-liquid piston is analysed, the theoretical equation and its time-averaged solution of pulsed liquid jet pump device efficiency are derived. The theoretical and experimental results show that the efficiency of transmission of energy and mass to use pulsed jet is greatly raised, compared with steady jet, in the same device of liquid jet pump. The calculating results of time-averaged efficiency of pulsed liquid jet pump are approximately in agreement with the experimental results in our and foreign countries

2001-03-01

21

The radio jet in NGC 6251  

International Nuclear Information System (INIS)

High-resolution observations are presented of the 300-kpc jet in the giant radio galaxy NGC 6251. The width of the jet is resolved over most of its length, and the axis of the jet wiggles with an amplitude increasing linearly with distance from the nucleus. Polarization data are used to derive densities of cold matter in the jet and, from the argument that the jet must form the lobe in a time equal to the age of the lobe, the speed of the jet is estimated as c/20. The energetics of the jet are then dominated by the bulk flow along it of cold matter at a rate of 1 solar mass yr"-"1. The jet appears to be confined; the wiggle of its axis is probably due to oscillations of the direction of the collimator with a period of about 6 x 10"6 yr. (author).

22

Jet cutting and cleaning bibliography  

Energy Technology Data Exchange (ETDEWEB)

This bibliography includes over 600 references (with abstracts) on all aspects of waterjet cutting and cleaning. The references are listed under the following chapter headings: fluid mechanics of jets; jet impact; equipment; jet cleaning; jet cutting; civil engineering; mining and tunnelling; precision cutting; underwater; safety; and bibliographies. Separate author and corporate source indexes are provided.

1988-01-01

23

Lockheed WP-3D Orion  

Science.gov (United States)

Approximately 62,000 lbs Fuel Load: 58,000 lbs. Type Fuel: JP4, JP5, JP8, JET A, JET A-1, JET B Standard Fuel Burn: 4500 - 6000 lbs/hr depending on altitude and airspeed Maximum...

2011-08-17

24

Gas Turbine Blade Heat Transfer Augmentation by Impingement of Air Jets Having Various Configurations.  

Science.gov (United States)

An experimental investigation of heat transfer characteristics for various configurations of air jets impinging on the leading edge inner surface of a gas turbine blade wall is presented. Three configurations were investigated, namely a slot jet, a round ...

1970-01-01

25

Experiments to investigate the effects of radiative cooling on plasma jet collimation  

CERN Document Server

Preliminary experiments have been performed to investigate the effects of radiative cooling on plasma jets. Thin (3 um - 5 um) conical shells were irradiated with an intense laser, driving jets with velocities > 100 km/s. Through use of different target materials - aluminium, copper and gold - the degree of radiative losses was altered, and their importance for jet collimation investigated. A number of temporally resoved optical diagnostics was used, providing information about the jet evolution. Gold jets were seen to be narrower than those from copper targets, while aluminium targets produced the least collimated flows.

2010-01-01

26

Toxicity of Jet A (Aviation Fuel) Selected Aquatic Organisms  

Science.gov (United States)

... Descriptors : *JET ENGINE FUELS, *AQUATIC ORGANISMS, *AVIATION FUELS, *TOXICITY, HEALTH, SMOKE SCREENS, WIND, WATER ...

1989-03-01

27

Sorption of Selected Volatile Organic Constituents of Jet Fuels ...  

Science.gov (United States)

... TITLE (Include Security Classification) Sorption of Selected Volatile Organic Constituents of Jet Fuels and Solvents on Natural Sorbents from Gas ...

1988-08-01

28

Questions and Answers on Changes to the Renewable Fuel Standard...  

Science.gov (United States)

fuel obligation under the RFS2 program for the production or importation of conventional jet fuel, RINs can be generated for renewable jet fuel. Is that right? A: As described in...

2011-08-18

29

CRC literature survey on the thermal oxidation stability of jet fuel. [Coordinating Research Council  

Science.gov (United States)

Two hundred eleven references from the period 1951 to 1978 are reviewed in this survey of literature on the thermal stability of jet aircraft fuels.

1979-01-01

30

Briefing on the Latest Sanctions on Iran  

Science.gov (United States)

of refined petroleum and energy traders have stopped sales of refined product to Iran. Jet fuel suppliers are now refusing to supply jet fuel to Iran Air at most destinations in...

2011-08-28

31

ADVANCED INTERNAL COMBUSTION ENGINE USING JET FUELS ...  

Science.gov (United States)

NASA 1996 STTR Phase I. Proposal Number: 960022. Project Title: ADVANCED INTERNAL COMBUSTION ENGINE USING JET FUELS FOR LIGHT AIRCRAFT ...

32

Thermal energy considerations on solar cavity wall building  

Energy Technology Data Exchange (ETDEWEB)

The dwelling is equipped with solar collectors which heat the air circulating in the cavity walls and the space beneath the floors. The thermal aspects of such a building are described. Heat balance, losses, heating by the sun in different seasons are described. Different measures taken to reduce the energy losses are described.

1983-02-01

33

Simple theory for predicting the natural convective energy loss from side-facing solar cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

A simple theory for predicting the convective energy loss from side-facing cavity receivers in windless environments has been developed. The approach used is to determine the velocity distribution of the incoming air in the aperture plane (and thereby the rate of mass entrainment); and then to estimate the bulk temperature of the heated emerging air. The convective loss is then calculated from an energy balance. To illustrate this theory, numerical results applicable to the 2.15 meter cubic cavity being tested in the laboratory are provided.

1981-01-01

34

Local secondary-electron emission spectra of graphite and gold surfaces obtained using the Scanning Probe Energy Loss Spectrometer (SPELS)  

International Nuclear Information System (INIS)

Secondary-electron emission (SEE) spectra have been obtained with the Scanning Probe Energy Loss Spectrometer at a tip-sample distance of only 50 nm. Such short working distances are required for the best theoretical spatial resolution (<10 nm). The SEE spectra of graphite, obtained as a function of tip bias voltage, are shown to correspond to unoccupied states in the electronic band structure. The SEE spectra of thin gold films demonstrate the capability of identifying (carbonaceous) surface contamination with this technique.

2009-11-25

35

Dynamics of high-energy nucleus-nucleus collisions  

Energy Technology Data Exchange (ETDEWEB)

The authors use a Glauber multiple-collision model to examine the dynamics of nucleus-nucleus collisions. The model introduces a stopping law, which describes how a baryon loses energy in a baryon-baryon collision, and a particle production law, which is based on the baryon energy loss. The model gives results on the longitudinal energy loss which compare well with the recent WA80 experimental data for /sup 16/O on various targets at 60 and 200 GeV per nucleon. The stopping law that is needed to fit the experimental zero-degree spectra reveals that the degree of stopping in these high-energy nuclear collisions is high.

1988-01-01

36

Absolute, cascade-free cross sections for the "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Absolute, cascade-free excitation cross sections in an ion have been measured for the resonance "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged electron-ion beams methods. Measurements were carried out at electron energies of below threshold to 6 times threshold. Comparisons are made with 2-, 5-, and 15-state close-coupling and distorted-wave theories. There is good agreement between experiment and the 15-state close-coupling cross sections over the energy range of the calculations.

37

A perspective of the Malaysian highway energy consumption and future power supply  

British Library Electronic Table of Contents (United Kingdom)

In this short communication, we discuss the energy consumption trends in the Malaysian road transport sector, with a special emphasis on the energy losses due to vehicle aerodynamic drag on highways. The recent trends of energy consumption in the Malaysian road transport sector are reviewed. It is evidently shown that the aerodynamic losses represented exceed 1.2MTOE annually since 2002. A novel concept of vertical-axis wind turbine (VAWT) farms for harvesting aerodynamic energy losses on Malaysian highways is preliminarily proposed. The novel concept aims at providing a sustainable and green energy source for the lighting of the highway network in the country.

2011-01-01

38

Jet initiation and penetration of explosives  

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional Eulerian hydrodynamic code 2DE, with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration ...

1983-01-01

39

Jet initiation and penetration of explosives  

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional Eulerian hydrodynamic code 2DE with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities ...

1983-01-01

40

Modelling of the wall jet in a direct injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

As a part of a phenomenological model, a method for simulating the wall/jet interaction in a direct injection diesel engine is proposed. The method is based on the application of the momentum conservation equation in the different directions in which the wall jet is spread, and takes into account both the interaction with the combustion chamber geometry and with swirl. It takes as initial conditions the results of calculating the free jet, which is divided into packages. The predictions provide good agreement with those by other researchers. (author).

1992-01-01

45

Coal liquefaction to increase jet fuel production  

Science.gov (United States)

Processing concept that increases supply of jet fuel has been developed as part of study on methods for converting coal to hydrogen, methane, and jet fuel. Concept takes advantage of high aromatic content of coal-derived liquids to make high-octane gasoline, instead of destroying aromatics to make jet fuel.

1979-01-01

47

Simplification of the scheme - Department of Energy and Climate Change  

Wastenet

...Simplification of the scheme - Department of Energy and Climate Change simplification, crc energy efficiency scheme Simplification of the scheme Simplification of the CRC Energy ...Efficiency Scheme The Government is considering the simplification of the CRC in the light of experience since the scheme began in April 2010. ...will take into account feedback from stakeholders including: the effectiveness of the CRC framework for driving energy efficiency in large private and public sector ... The perceived complexity of the CRC scheme and hence the administrative burden on: - those organisations that are subject to ...

48

Jet plume injection and combustion system for internal combustion engines  

Energy Technology Data Exchange (ETDEWEB)

This invention is comprised of an improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been ...

1992-12-31

49

JET contribution to ITER fuel cycle issues  

Energy Technology Data Exchange (ETDEWEB)

The Joint European Torus (JET) fusion machine is the only device capable of operation with tritium (as fuel) and Be (as plasma facing component), what makes it best suited to study ITER relevant issues. A large variety of activities are performed within the JET Fusion Technology Task Force. In this paper, some topics such as erosion/deposition and material transport, flakes characterization and detritiation techniques are highlighted. Recent results obtained using a pumping cryo-panel and on plasma facing component characterisation are given. Finally, issues that will be addressed in the forthcoming JET work-programme are presented, such as a beryllium main wall for JET and in-situ laser detritiation. (authors)

2005-07-01

50

Characterization of jet breakup mechanisms observed from simulant experiments of molten fuel penetrating coolant  

Science.gov (United States)

The goal of this research program has been to add to our understanding of the breakup of molten fuel jets penetrating reactor coolant. Easily handled working fluids are used to simulate fuel jet breakup, so that detailed observations may be obtained from a relatively large number of experiments. The tools used for observing this behavior are high speed notion picture photography, Flash X-radiography, and X-ray cine. Jet breakup lengths are determined from motion pictures; the mechanisms by which the jets are fragmented may be inferred from radiographs.

1992-01-01

54

Thermal Interaction Between Molten Metal Jet and Sodium Pool: Effect of Principal Factors Governing Fragmentation of the Jet  

International Nuclear Information System (INIS)

To clarify the effects of the principal factors that govern the thermal fragmentation of a molten metallic fuel jet in the course of fuel-coolant interaction, which is important in evaluating the sequence of core disruptive accidents (CDAs) for metallic fuel fast reactors, basic experiments were carried out using molten metallic fuel simulants (copper and silver) and a sodium pool.Fragmentation of a molten metal jet with a solid crust was caused by internal pressure produced by the boiling of sodium, which is locally entrapped inside the jet due to hydrodynamic motion between the jet and the coolant. The superheating and the latent heat of fusion of the jet are the principal factors governing this type of thermal fragmentation. On the other hand, the effect of the initial sodium temperature is regarded as negligible in the case of thermal conditions expected to result in CDAs for ...

2005-02-01

55

Segmentation and fragmentation of melt jets due to generation of large-scale structures. Observation in low subcooling conditions  

Energy Technology Data Exchange (ETDEWEB)

In order to clarify a mechanism of melt-jet breakup and fragmentation entirely different from the mechanism of stripping, a series of experiments were carried out by using molten tin jets of 100 grams with initial temperatures from 250degC to 900degC. Molten tin jets with a small kinematic viscosity and a large thermal diffusivity were used to observe breakup and fragmentation of melt jets enhanced thermally and hydrodynamically. We observed jet columns with second-stage large-scale structures generated by the coalescence of large-scale structures recognized in the field of fluid mechanics. At a greater depth, the segmentation of jet columns between second-stage large-scale structures and the fragmentation of the segmented jet columns were observed. It is reasonable to consider that the segmentation and the fragmentation of ...

1999-07-01

56

Modeling of thermal and hydrodynamic aspects of molten jet/water interactions  

Energy Technology Data Exchange (ETDEWEB)

In order to predict the effect of a fuel-coolant interaction after a hypothetical core-melt-down accident, a phenomenological model has been developed to describe the thermal and hydrodynamic behavior of a high-temperature molten jet when it interacts with saturated or subcooled water in a film boiling regime. The mechanisms of jet-material erosion were analyzed by Kelvin-Helmholtz instabilities on the coherent column and by boundary layer stripping on the leading edge. The heat transfer coefficient, vapor-film thickness, and net steam generation, all of which strongly affect the jet-breakup behavior, were solved analytically. It was found that the jet breakup (or erosion) depends strongly on the steam generation from the jet/water interaction. The jet-breakup length (i.e., penetration distance) was found to be sensitive to the initial jet ...

1989-01-01

57

Subsolutions of an Isaacs Equation and Efficient Schemes for ...  

Science.gov (United States)

... analyze importance sampling schemes for stochastic networks ... an interesting mixed open/closed queueing network ... with a suitable terminal condition ...

2005-08-08

58

Inelastic-energy-loss measurements of multiple N- and M-shell excitations in 0.3- to 1.2-MeV Xe"+-Xe collisions  

International Nuclear Information System (INIS)

The inelastic energy losses for single collisions of Xe"+ ions with Xe targets have been measured for incident ion energies from 0.3 to 1.2 MeV and for scattering angles from 3"0 to 20"0. The energy losses were found to range from 1 to 11 keV with distinct steps at distances of closest approach of 0.22 and 0.12 A. By comparing these data with earlier ionization data by the same authors these steps are shown to be caused by M-shell excitation. Other excitations observed in the ionization data may be attributed to N-shell excitation. The distances of closest approach at which these excitations occur agree well with calculations by Eichler and Wille and co-workers, giving further evidence of the usefulness of Fano and Lichten's one-electron molecular model and these calculations.

59

The competition of neutrino energy loss due to the pair, photo-, plasma process at the late stages of stellar evolution  

International Nuclear Information System (INIS)

Based on the Weinberg-Salam theory, the competition of the Neutrino Energy Loss (NEL) rates due to the pair, photo- and plasma process are canvassed. The ratio factor C1, C2 and C3 which correspond the different contributions of the pair, photo- and plasma neutrino process to those of the total NEL rates are accurately taken into account. The ratio factors are very sensitive to the temperature and density. The ratio factor C2 always is lower than the ratio factor C1 and C3. The pair NEL process is the dominant contribution before the crossed point O(C1=C3=0.45) and the plasma NEL process will be the main dominant contribution after the crossed point O. With increasing temperature, the crossed point O will move to the direction of higher density. (authors)

2009-01-01

60

Status of research on convective losses from solar central receivers  

Energy Technology Data Exchange (ETDEWEB)

Progress in the worldwide capability of predicting the convective energy loss from solar central receivers is reviewed. The significant advances in the past three years have been in experimental areas. Baseline measurements of the convective heat transfer from large high-temperature surfaces, e.g., a flat plate and a cubical cavity, have been completed and empirical correlations have been obtained. Theoretical modeling activities have not kept pace with the experimental advances, however. Currently, the primary theoretical emphasis is the development and testing of turbulence models suitable for buoyant flows. Three major needs have been identified: the measurement of convective energy losses from operating solar central receivers; the continued development of theoretical models in spite of the relatively slow progress to date; and the quantification of the effects of atmospheric turbulence.

1983-06-01

61

Measurements of vibrational excitation of N_2, CO, and NO by low energy proton impact  

International Nuclear Information System (INIS)

Differential scattering experiments are reported for proton impact on N_2, CO, and NO in the energy range E/sub lab/=30--80 eV. The measurements include the range of very small scattering angles around 0"0 as well as the rainbow region. The vibrationally resolved energy-loss spectra show a relatively low vibrational inelasticity for all three systems. Differential cross sections, transition probabilities, and the mean vibrational energy transfer are presented. Rotational excitation is indicated by the broadening of the energy-loss peaks which is most significant for H"+--NO. The small-angle scattering data for vibrational excitation in CO show good agreement with the impact parameter theory using the known long-range interactions for this system.

1979-07-01

62

Magnetospheric particle acceleration and X-ray emission of pulsars  

CERN Document Server

The available data on isolated X-ray pulsars, their wind nebulae, and the supernova remnants which are connected to some of these sources are analyzed. It is shown that electric fields of neutron stars tear off charged particles from the surface of neutron star and trigger the acceleration of particles. The charged particles are accelerated mainly in the field of magneto-dipole radiation wave. Power and energy spectra of the charged particles depend on the strength of the magneto-dipole radiation. Therefore, the X-ray radiation is strongly dependent on the rate of rotational energy loss and weakly dependent on the electric field intensity. Coulomb interaction between the charged particles is the main factor for the energy loss and the X-ray spectra of the charged particles.

2007-01-01

63

Electron-impact excitation of Si"3"+(3s#->#3p) using a merged-beam electron-energy-loss technique  

International Nuclear Information System (INIS)

For the first time, absolute cross sections for electron-impact excitation of a multiply charged ion have been measured using an electron-energy-loss technique. Cross sections for e+Si"3"+(3s "2S_1_/_2)#->#e+Si"3"+(3p "2P_1_/_2_,_3_/_2)-8.88 eV have been measured with an accuracy of #+-#20% (at 90% confidence level) over a narrow energy range (#+-#0.6 eV) about the threshold energy with an energy resolution of 0.2 eV. Results are in good agreement with close-coupling calculations.

64

Acceleration of particles in pulsar magnetosphere and the X-ray radiation  

CERN Document Server

The available data of single X-ray pulsars, their wind nebulae, and the SNRs which are connected to some of these sources are analysed. It is shown that electric field intensity of neutron stars tears off charged particles from the surface of neutron star and triggers the acceleration of particles. The charged particles are accelerated mainly in the field of magnetodipole radiation wave. Power and energy spectra of the charged particles depend on the strength of the magnetodipole radiation. Therefore, the X-ray radiation is strongly dependent on the rate of rotational energy loss and weakly dependent on the electric field intensity. Coulomb interaction between the charged particles is the main factor for the energy loss and the X-ray spectra of the charged particles.

2004-01-01

65

Absolute electron scattering cross sections for the "2S#->#"2P transition in Zn"+ using energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Using the electron energy-loss method in a merged electron-ion beams geometry absolute, cascade-free excitation cross sections have been measured for the resonance "2S#->#"2P transition in Zn"+. Measurements were carried out at electron energies of below threshold (threshold at 6.011 eV) to 40 eV. Results are in very good agreement with close-coupling calculations and, away from threshold, lie below absolute line-emission cross sections which include effects of cascade into the "2P state from higher levels.

1991-02-20

66

Performance of the gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator GARIS for the 238U (22Ne, 5n)255No reaction  

International Nuclear Information System (INIS)

The performance of the gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator GARIS was investigated using 255No produced in the 238U(22Ne, 5n)255No reaction. Alpha particles of 255No separated with GARIS and transported by the gas-jet system were measured with a rotating wheel apparatus for ? spectrometry under low background condition. The high gas-jet efficiencies of about 75% were independent of the recoil ranges of 255No in the gas-jet chamber. The present results suggest that the GARIS/gas-jet system is a promising tool for the next-generation superheavy element chemistry: (1) the background radioactivities of unwanted reaction products are strongly suppressed, (2) the intense beam is absent in the gas-jet chamber and hence the high gas-jet efficiency is achieved, and (3) the beam-free condition also allows for ...

2008-08-01

67

Multi-Stream Saline-Jet Dissection Using a Simple Irrigation System Defines Difficult Tissue Planes  

UK PubMed Central (United Kingdom)

Introduction:Single-stream hydro-jet dissection is increasingly used in various laparoscopic procedures, but its use requires special equipment. We describe a simple method for using...Full Text Available

2010-01-01

68

Heat Transfer Augmentation in Turbulent Impinging Jets.  

Science.gov (United States)

Heating and cooling by impinging jets is widely used in various engineering applications, due to the high heat transfer rates prevailing in the vicinity of the stagnation point. The authors have been able to utilize acoustically excited turbulence for the...

1979-01-01

69

Experimental simulation of heat transfer augmentation by break-jets in passive containment cooling system  

International Nuclear Information System (INIS)

The studies of forced jet augmentation of natural convection heat transfer are introduced. It investigates experimentally mixed convection and heat transfer augmentation by forced jets in a large rectangular enclosure with a vertical cooling surface. The experiment is designed to measure the key parameters governing the heat transfer augmentation by a forced jet, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio, on conditions simulating those of actual passive containment cooling systems and scales approaching those of actual containment buildings or compartments. The tests that cover a variety of injection modes will contribute to reveal the nature of mixing and stratification phenomena under accident conditions to a new generation of inherently safe reactors. With similarity ...

2010-02-01

70

State of the energy in Lebanon  

International Nuclear Information System (INIS)

The article describes the state of the energy in Lebanon. In 1996, Lebanon consumed 4647 Ktoe as a primary energy. 97% of this energy is imported mainly polluting oil products: 1623 Ktons fuel-oil, 1379 Ktons gasoline, 930 Ktons diesel, 200 Ktons coal, 124 Ktons LPG, 107 Ktons jet-fuel/Kerosene, 109 Ktons Asphaltic products. The remaining 3% of the energy consumption is renewable energy. As for production, the state owns two refineries which are not used anymore. The year 2000 plan includes an expansion project for the Tripoli refinery and an alternative plan for the Zahrani refinery. These refineries require a total investment in order to reach a production capacity of 50000 barrels a day. The article is a description of the pollution type sources and location in Lebanon. The combustion of the total energy produces yearly more than 15 Ktons of dust, 85 Ktons of SO_2, 40 Ktons of NOX and 3500 Ktons of CO_2. Another risk of pollution is due to spilling oil along the ...

1998-04-01

71

Lifetime measurements of singlet ungerade states in isotopic molecular nitrogen  

International Nuclear Information System (INIS)

Full text: In the upper layers of the Earth's atmosphere, molecular nitrogen absorbs the extreme ultraviolet (XUV) solar radiation. The absorption is associated with dipole-allowed excitation of states of singlet ungerade symmetry ("1#SIGMA#"+_u and "1#PI#_u), which are known to undergo predissociation due to coupling with a mainfold of "1#PI#_u states. We determined new N_2 isotopic lifetimes of many "1#SIGMA#"+_u and "1#PI#_u states via line broadening measurements in the frequency domain. Ultrahigh resolution XUV + UV ionization spectra were recorded (bandwidth #approx# 250 MHz, resolving power 10"7), from which the natural linewidth, i.e. lifetime, was determined. These lifetimes provide new information about the predissociation of the singlet ungerade states in N_2. Tunable narrowband XUV radiation was produced by successively pulsed amplification of cw dye laser radiation, frequency doubling the pulsed visible laser beam into the UV and frequency tripling the UV in a xenon ...

2004-07-19

72

Theoretical Calculation of Jet Fuel Thermochemistry  

Science.gov (United States)

High-level ab initio calculations have been performed on the exo and endo isomers of gas-phase

2010-01-01

73

Experimental investigation of the length of a free diffusion jet of fuel gases diluted with inert gases  

Science.gov (United States)

Experimental investigation of the length of single burning jets of methane and hydrogen previously diluted with an inert gas (nitrogen or helium) was carried out. Efflux of fuel gases into the atmosphere occurred through cylindrical extension pieces 4 and 8 mm in diameter. The Reynolds numbers at the cut of a piece varied in the range from 400 to 12,000. A clearly defined dependence of the jet length on the quality of the added inert gas is obtained. The correlation of experimental data made it possible to recommend formulas for engineering calculations of free laminar and turbulent jets.

2010-05-01

74

Energy and Water Conservation  

Science.gov (United States)

Jet Propulsion Laboratory. California Institute of Technology. Pasadena, California. Energy and Water Conservation. Steve Rigdon. Facilities Energy Manager ...

75

Aerosol spectral optical depths - Jet fuel and forest fire smokes  

Science.gov (United States)

The Ames autotracking airborne sun photometer was used to investigate the spectral depth between 380

1990-01-01

76

The JET (Joint European Torus) multipellet launcher and fueling of JET plasmas by multipellet injection  

Energy Technology Data Exchange (ETDEWEB)

A new multipellet long-pulse plasma fueling system is in operation on JET. In the initial experimental phase, a variety of plasma density profile shapes have been produced with peak to average values ranging up to 2.5 and peak plasma density up to 1.2 )times) 10/sup 20/m/sup )minus/3). 7 refs., 4 figs

1988-01-01

77

Physical Modelling of Axisymmetric Turbulent Impinging Jets as used within the Nuclear Industry for Mobilisation of Sludges  

Energy Technology Data Exchange (ETDEWEB)

The impingement of a fluid jet onto a surface has broad applications across many industries. Within the UK nuclear industry, during the final stages of fuel reprocessing, impinging fluid jets are utilised to mobilise settled sludge material within storage tanks and ponds in preparation for transfer and ultimate immobilisation through vitrification. Despite the extensive applications of impinging jets within the nuclear and other industries, the study of two-phase, solid loaded, impinging jets is limited, and generally restricted to computational modelling. Surprisingly, very little fundamental understanding of the turbulence structure within such fluid flows through experimental investigation is found within the literature. The physical modelling of impinging jet systems could successfully serve to aid computer model validation, determine operating requirements, evaluate plant ...

2008-07-01

78

Photon final states at the Tevatron  

Energy Technology Data Exchange (ETDEWEB)

The authors present here several recent measurements involving associate production of photons and jets at the Tevatron. In particular, inclusive photon + met from D0, and photon + b-jets and photon + b-jet + leptons + MET from CDF are described in some detail. These measurements offer a good test of QCD predictions in rather complex final states.

2008-04-01

79

Influence of the jet pressure ratio on the performance of an AGARD single flow afterbody in the 0.60-0.95 Mach range  

Science.gov (United States)

The synthesis of experimental data concerning the effect of jet stagnation conditions on the drag of various afterbodies is presented. Jet pressure ratio effect on boattail pressure and on boundary layer separation is analyzed. This study is made for several values of the boundary layer thickness, taking into account the fact that some test rigs make its control possible by means of tangential blowing.

1975-10-01

80

Gas-temperature-dependent generation of cryoplasma jet under atmospheric pressure  

International Nuclear Information System (INIS)

Plasma with a gas temperature below room temperature is not yet fully understood although it is expected to be an attractive tool for applications to material processing. In the present work, gas-temperature-dependent generation of a cryoplasma jet was studied. So far, we have generated a helium cryoplasma jet (296-5 K) under atmospheric pressure. At gas temperatures below 20 K, the helium excimer, He2, was observed clearly from by optical emission spectroscopy.

2008-09-08

81

Experimental investigation of mixed convection heat transfer caused by forced-jets in large enclosure  

Energy Technology Data Exchange (ETDEWEB)

This research investigates experimentally mixed convection and heat transfer augmentation by forced jets in a large enclosure, at conditions simulating those of actual passive containment cooling systems and scales approaching those of actual containment buildings or compartments. The experiment was designed to measure the key parameters governing the heat transfer augmentation by forced jets and investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest that contribute to reveal the nature of mixing and stratification phenomena in the containment under accident conditions of interest. The heat transfer of mixed convection can be predicted to be controlled by jet Archimedes number and geometric factors. ...

2004-07-01

82

Effects of Chronic JP-8 Jet Fuel Exposure on Lung Function.  

Science.gov (United States)

The past three years of work for the Air Force Office of Scientific Research has resulted in the development of a congenic mouse model of JP-8 jet fuel exposure, the role of substance P in the JP-8 jet fuel-induced lung injury process, and development of ...

1997-01-01

83

Development of a new secondary beam separator and a new gas-jet target at Kyushu University  

International Nuclear Information System (INIS)

In order to facilitate observations of low energy nuclear reactions, a new type recoil mass-separator together with a new gas-jet target system is being developed at the tandem accelerator facility in Kyushu University. The expected mass-resolving power of the separator is 220 for a solid angle of 10 msr and the practical thickness of the gas-jet target will exceed 0.1 atm#centre dot#cm for the light elements of H and He. (author).

1994-06-01

84

Acute Toxicity Evaluation of JP-8 Jet Fuel and JP-8 Jet Fuel Containing Additives.  

Science.gov (United States)

To reduce fuel fouling in current U.S Navy and Air Force aircraft systems and to provide additional heat sink and thermal stability for future systems, the Air Force is developing an improved JP-8 jet fuel (JP-8 + 100). Two companies (Betz and Mobil) have...

1996-01-01

85

What can we learn about extragalactic radio jets from X-ray data?  

CERN Document Server

We review the current status of resolved X-ray emission associated with extragalactic radio jets and hotspots. The primary question for any particular jet is to decide if the X-rays come from the synchrotron process or from inverse Compton scattering. There is considerable evidence supporting synchrotron emission for knots in the jets of FRI galaxies. For FRII terminal hotspots detected in the X-ray band, synchrotron self-Compton emission continues to provide viable models with one possible exception (so far). Inverse Compton scattering on photons of the cosmic microwave background is indicated for a few powerful jets, and is expected to be an important contributor if not the dominating mechanism for higher redshift objects. The application of a model generally yields physical parameters and in many cases, these include the Doppler boosting factor.

2003-01-01

86

Quasi-stationary and transient patterns in jets  

Science.gov (United States)

Apparent evolution of relativistic flows as traced by radio emission results from a combination of several factors related to propagation of relativistic blobs or shocks, velocity, density and pressure stratification of the underlying flow, plasma instability and (possibly also) phase and time travel effect. This combination can create an intricate and chaotic patterns of the observed morphological changes in radio emission, which complicates the analysis and interpretation of kinematic and physical properties of the jet plasma. Recent studies have indicated that slow and quasi-stationary patterns in jets are most likely formed by plasma instabilities while faster, superluminally moving patterns are related to highly relativistic plasma condensations produced by the nuclear flares. Some of the stationary patterns may also be related to recollimation shocks or locations where strong non-thermal continuum is produced in jets. ...

2011-01-01

87

Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA  

Energy Technology Data Exchange (ETDEWEB)

Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.

2001-02-26

88

Investigation of mixed convection in a large rectangular enclosure  

Energy Technology Data Exchange (ETDEWEB)

This experimental research investigates mixed convection and heat transfer augmentation by gaseous forced jets in a large enclosure, at conditions simulating those of passive containment cooling systems for Gen III+ passively safe reactors. The experiment is designed to measure the key parameters governing heat transfer augmentation by forced jets, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest for mixing and stratification phenomena in containments under accident conditions. Correlations for heat transfer augmentation by forced jets are developed and compared with experimental data. The characteristic recirculation speed inside the enclosure is introduced and analyzed. Steady stratified ...

2007-05-15

89

Investigation of mixed convection in a large rectangular enclosure  

International Nuclear Information System (INIS)

This experimental research investigates mixed convection and heat transfer augmentation by gaseous forced jets in a large enclosure, at conditions simulating those of passive containment cooling systems for Gen III+ passively safe reactors. The experiment is designed to measure the key parameters governing heat transfer augmentation by forced jets, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest for mixing and stratification phenomena in containments under accident conditions. Correlations for heat transfer augmentation by forced jets are developed and compared with experimental data. The characteristic recirculation speed inside the enclosure is introduced and analyzed. Steady stratified ...

2007-05-01

90

A pump-probe XFEL particle injector for hydrated samples  

CERN Document Server

We have developed a liquid jet injector system that can be used for hydrated sample delivery at X-ray Free Electron Laser (XFEL) sources and 3rd generation synchrotron sources. The injector is based on the Gas Dynamic Virtual Nozzle (GDVN), which generates a liquid jet with diameter ranging from 300 nm to 20 {\\mu}m without the clogging problems associated with conventional Rayleigh jets. An improved nozzle design is presented here. A differential pumping system protects the vacuum chamber and an in-vacuum microscope allows observation of the liquid jet for diagnostics while it is being exposed to the X-ray beam. A fiber optically coupled pump laser illuminating the jet is incorporated for pump-probe experiments. First results with this injector system have been obtained at the LCLS.

2011-01-01

91

Turbo expanders for separation of gas mixtures by partial condensation  

International Nuclear Information System (INIS)

Thermodynamic consideration and process calculations at equilibrium conditions showed that processes for separating gas mixtures by partial condensation at low temperatures using turboexpanders have got less energy losses than processes with quasi isobar partial condensation. Compared to the low-pressure parts of condensing steam turbines in turboexpanders less erosion problems are to expected for such separating processes. Separation of liquid in the machine, however, is more difficult withouf additional measures. (orig.).

92

Origin of the low-energy cosmic-ray antiprotons  

Energy Technology Data Exchange (ETDEWEB)

A model for generating the observed cosmic-ray antiproton spectrum in plasma consisting mainly of electron--positron pairs (n/sub plus-or-minus//n/sub p/> or approx. =10) is discussed. Coulomb collisions in the plasma would cause additional energy losses, significantly enhancing the antiproton flux at energies < or approx. =1 GeV. The computed p-bar/p ratio satisfactorily fits the observations.

1983-01-01

93

Optimal selection of capacitors for radial distribution systems using a genetic algorithm  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a new design methodology for determining the size, location, type and number of capacitors to be placed on a radial distribution system is presented. The objective is to minimize the peak power losses and the energy losses in the distribution system considering the capacitor cost. A sensitivity analysis based method is used to select the candidate locations for the capacitors. A new optimization method using a Genetic Algorithm is proposed to determine the optimal selection of capacitors. Test results have been presented along with the discussion of the algorithm.

1994-08-01

94

Nitrogen isotope identification by Bragg-curve spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Projectilelike fragments following the 80 MeV /sup 16/O+/sup 27/Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

1984-07-14

95

Nitrogen isotope identification by Bragg-curve spectroscopy  

International Nuclear Information System (INIS)

Projectilelike fragments following the 80 MeV "1"6O+"2"7Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

96

Nature of low-energy antiprotons in cosmic rays  

Energy Technology Data Exchange (ETDEWEB)

A model of formation of cosmic ray antiproton spectrum in plasma consisting mainly of electron-positron pairs (nsub(+-)/nsub(p) > or approximately 10) is considered. Additional energy losses due to Coulomb collisions in plasma provide significant increase of the antiproton flux in the energy range < or approximately 1 GeV. Calculated anti p/p ratio is in a satisfactory agreement with the observational data.

1983-02-01

97

Experimental and evaluated nuclear plus interference cross sections for light charged particles  

Energy Technology Data Exchange (ETDEWEB)

Experimental and evaluated integral parameters derived from nuclear plus interference differential elastic scattering cross sections are presented for all projectile/target combinations of the particles p, d, t, /sup 3/He, and ..cap alpha... The data include reaction rates, average fractional energy losses per collision and per unit path length, and average laboratory scattering cosines. The resulting parameters are of potential use in analysis of charged-particle transport.

1980-07-04

98

Atomic interactions of charged particles with matter  

Energy Technology Data Exchange (ETDEWEB)

Ideas about the interactions of charged particles with matter are discussed. First, some experimental information is presented. Concepts related to collision cross sections and the Bethe model for them are given. The stopping power is derived and applied to the discussion of depth dose functions ('Bragg curves'). Some details of the energy loss in microscopic volumes are discussed.

1993-04-01

99

Application of neural networks to pulse-shape analysis of Bragg curves  

Energy Technology Data Exchange (ETDEWEB)

A novel approach is presented to extract relevant parameters associated with the energy loss of ejectiles from nuclear reactions obtained by digitizing the signals of a Bragg curve spectrometer. New and more powerful computational paradigms allow a more thorough pulse-shape analysis. This is fulfilled using a back-propagation artificial neural network as a pattern identifier. The known problem of over-training is discussed.

2006-01-15

100

X-ray and HeI 1.0830 mu emission from protostellar jets  

CERN Document Server

Context. The high energies of protostellar jets, implied by recent observations of X-rays from such flows, came very much as a surprise. Inferred shock velocities are considerably higher than what was previously known, hence putting even larger energy demands on the driving sources of the jets. The statistics of X-ray emitting jets are still poor, yet a few cases exist which seem to imply a correlation between the presence of HeI 1.0830 mu emission and X-ray radiation in a given source. Aims. This tentative correlation needs confirmation and explanation. If the jet regions of HeI 1.0830 mu emission are closely associated with those producing X-rays, high resolution infared spectroscopy can be used to observationally study the velocity fields in the hot plasma regions of the jets. This would provide the necessary evidence to test and further develop theoretical models of ...

2006-01-01

101

Structure and evolution of the stabilization point of a lifted reacting jet  

Energy Technology Data Exchange (ETDEWEB)

In this work the authors study the stabilization point of a lifted, reacting jet of nitrogen diluted methane in co-flowing air. The jet flow is acoustically forced so as to organize the large scale vortical structures. The validation of the numerical results is possible through a concurrent experimental investigation of a similar planar jet. The use of an acoustically forced planar jet allows for significant savings by the restriction of the computation to two dimensions; the model is otherwise applicable in three dimensions. The authors based their study on the following parameters, which are derived from the experimental setup: a jet width of 1.16 cm, a mean jet velocity of 0.8 m/s, and a coflow velocity of 0.1 m/s. The acoustical forcing is studied at frequencies of 7.5 MHz and 90 MHz, which have been established experimentally as being characteristic of two ...

1997-11-01

102

Quark and Gluon Tagging at the LHC  

CERN Document Server

Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing and novel jet substructure observables, we find that a multivariate approach can filter out over 95% of the gluon jets while keeping more than half of the light-quark jets. Moreover, a combination of two simple variables, the charge track multiplicity and the pT-weighted linear radial moment (girth), can achieve similar results. While this pair appears very promising, our study is only Monte Carlo based, and other discriminants may work better with real data in a realistic experimental environment. To that end, we explore many other observables constructed using different jet sizes and parameters, and highlight those that deserve further ...

2011-01-01

103

Fluid dynamics of jet-forming elements of contact devices with directional gas stream injection  

International Nuclear Information System (INIS)

One way to intensify heat and mass transfer processes in column-type equipment is through use of contact devices with directional gas phase injection into a liquid. Making the perforations at an angle to the tray plane permits a rise in the permissible gas velocity in the column, since inertial force adds to gravity during separation. Different arrangements of the jet-forming elements relative to one another and to partitions and baffle-type contacts installed on the trays can improve phase contact conditions and intensify heat and mass transfer. Design of jet-type trays for a specific purpose requires that the influence of jet-forming, element design parameters on at least the fluid dynamic situation on the tray be known. In this work, the authors evaluate the influence of tab bend-up angle on jet tray working characteristics. These investigations demonstrate that the jet ...

104

Computational study of jet interaction flow field with and without incidence  

International Nuclear Information System (INIS)

The objective was to study the interaction of a side jet with the incoming supersonic flow and hypersonic flow. Qualitatively same Cp trends have been obtained as found experimentally. Also in aerodynamic coefficients side jet interaction results in additional pitching moment which is because of the high pressure region in upstream of the jet and a low pressure region in the downstream of the jet. Also jet interaction results in the rise in the lift coefficient. Whereas in the incidence case, simulation has been performed for the hypersonic flows over a biconic body with supersonic lateral jet at Mach 9.7 and incidence of 0"o to incidence of -12"o and 12"o. The results obtained were compared with the experimental and CFD code CFL3D results. PAK-3D over predicts the surface pressure as compared to the CFL3D and experimental results, whereas the qualitative trends ...

2004-05-09

105

Scheme for Entangling Two Distant Cavity Mirrors  

International Nuclear Information System (INIS)

A scheme is presented for the generation of entangled states for two cavity mirrors. In the scheme each mirror initially in a vacuum state interacts with a weak coherent field, resulting in a photon-number dependent kick. The detection of a photon leaking from the cavities collapses the two mirrors to an entangled state.

2008-04-15

106

Controlled Bidirectional Quantum Direct Communication by Using a GHZ State  

Science.gov (United States)

A controlled bidirectional quantum secret direct communication scheme is proposed by using a Greenberger-Horne-Zeilinger (GHZ) state. In the scheme, two users can exchange their secret messages simultaneously with a set of devices under the control of a third party. The security of the scheme is analysed and confirmed.

2006-07-01

107

Asymptotically Optimal Tree-based Group Key Management Schemes  

CERN Document Server

In key management schemes that realize secure multicast communications encrypted by group keys on a public network, tree structures are often used to update the group keys efficiently. Selcuk and Sidhu have proposed an efficient scheme which updates dynamically the tree structures based on the withdrawal probabilities of members. In this paper, it is shown that Selcuk-Sidhu scheme is asymptotically optimal for the cost of withdrawal. Furthermore, a new key management scheme, which takes account of key update costs of joining in addition to withdrawal, is proposed. It is proved that the proposed scheme is also asymptotically optimal, and it is shown by simulation that it can attain good performance for nonasymptotic cases.

2005-01-01

108

Search for new physics in the jets and missing transverse energy topology with the D0 detector at the Tevatron; Recherche de nouvelle physique dans la topologie a jets et energie transverse manquante avec le detecteur D0 au TeVatron  

Energy Technology Data Exchange (ETDEWEB)

Although the standard model of particle physics agrees perfectly with experimental data, it is unlikely the final theory describing particles and their interactions. New phenomena has been searched in the jets and missing transverse energy topology. Such phenomena may be due to the pair production of leptoquarks decaying into a quark and a neutrino or the pair production of stops decaying into a charm and a neutralino which is assumed to be the lightest supersymmetric particle. These searches have been performed with the Ddiamter detector at hadronic collider TeVatron with a center of mass energy of 1.96 TeV. This kind of searches needs a good understanding of the jet energy calibration. The determination of the relative jet energy scale has allowed us to reduce the systematic uncertainties on the jet energy measurement when comparing the data and the simulation. Moreover a new method has been developed ...

2006-05-15

109

Pre-Flight Development of the PoGOLite Pathfinder  

International Nuclear Information System (INIS)

The Polarized Gamma-ray Observer (PoGOLite) is a balloon-borne instrument that will measure gamma-ray polarization in the energy range 25-80 keV from astronomical sources such as pulsars, accretion discs and jets from active galactic nuclei. The two additional parameters provided by such observations, polarization angle and degree, will allow these objects to be studied in a new way, providing information about their emission mechanisms and geometries. The instrument measures azimuthal scattering angles of photons within a close packed array of phoswich detector cells (PDCs) based on coincident detection of Compton scattering and photoelectric absorption. Each PDC comprises three different scintillating components and combines photon detection, active collimation and bottom anticoincidence into one single unit. The three parts are viewed by a photomultiplier tube (PMT) and pulse shape discrimination is used to identify signals from dierent parts. Surrounding the ...

110

A Scheme of 3-D Breakdown-whip Analysis Methodology for High Energy Piping  

Energy Technology Data Exchange (ETDEWEB)

High energy piping systems are operated with either or both conditions of maximum operating temperature exceeding 200 .deg. F(93.3 .deg. C) or maximum operating pressure exceeding 275 psig(19.3kg/cm{sup 2}) during normal operating conditions in nuclear power plants. A high energy pipe failure is postulated in branches or piping that runs larger than one inch nominal diameter. The resultant consequences of these postulated pipe breaks must be analyzed for the effect on maintenance of plant safe shutdown capability, containment integrity. And the analyzed results must be applied to the system design so that a pipe failure can not damage essential systems to an extent of impairing design function nor affect necessary component operability. The considerable effects of pipe break are as follows; dynamic effects such as pipe whip, jet impingement and environmental impact by release of system contents. Two types of forces are occurred by the pipe whip. The one is pipe ...

2007-10-15

111

The infrared-dominated jet of 3C401  

CERN Document Server

We present a Hubble Space Telescope image of the FRII radio galaxy 3C 401, obtained at 1.6 microns with the NICMOS camera in which we identify the infrared counterpart of the brightest region of the radio jet. The jet has a complex radio structure and brightens where bending occurs, most likely as a result of relativistic beaming. We analyze archival data in the radio, optical and X-ray bands and we derive its spectral energy distribution. Differently from all of the previously known optical extragalactic jets, the jet in 3C401 is not detected in the X-rays even in a long 48ksec X-ray Chandra exposure and the infrared emission dominates the overall SED. We propose that the dominant radiation mechanism of this jet is synchrotron. The low X-ray emission is then caused by two different effects: i) the lack of any strong external photon field and ii) the shape of the electron ...

2005-01-01

112

Suzaku and Optical Spectroscopic Observations of SS 433 in the 2006 April Multiwavelength Campaign  

CERN Document Server

We report results of the 2006 April multi-wavelengths campaign of SS 433, focusing on X-ray data observed with Suzaku at two orbital phases (in- and out-of- eclipse) and simultaneous optical spectroscopic observations. By analyzing the Fe25 K_alpha lines originating from the jets, we detect rapid variability of the Doppler shifts, dz/dt ~ 0.019/0.33 day^-1, which is larger than those expected from the precession and/or nodding motion. This phenomenon probably corresponding to "jitter" motions observed for the first time in X-rays, for which significant variability both in the jet angle and intrinsic speed is required. From the time lag of optical Doppler curves from those of X-rays, we estimate the distance of the optical jets from the base to be ~(3-4) \\times 10^14 cm. Based on the radiatively cooling jet model, we determine the innermost temperature of the jets to be T_0 = 13 +/- ...

2010-01-01

113

Modeling jet penetration in glass  

Energy Technology Data Exchange (ETDEWEB)

It is well known that composite armors, consisting of glass elements confined with metallic tampers, are extraordinarily effective against shaped charge attack. Early experiments showed that jets fired against glass targets appeared to be bombarded by tiny fragments that destroyed alignment and reduced residual jet penetration. This result was attributed to an elastic rebound effect in which the outward radial motion of the target around the jet periphery was supposed to be arrested by tensile hoop stresses which developed behind the divergent shock front. Glass fragments were then accelerated radially inward and these destabilized the jet. To sustain the large tensile hoop stresses required, the glass must not have been fractured by the initial shock, behind which the stress state is typically well above the Hugoniot elastic limit. Modeling the penetration of a jet into glass ...

1990-04-05

114

Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels  

Energy Technology Data Exchange (ETDEWEB)

A transition from petroleum~derived jet fuels to blends with Fischer-Tropsch (F~T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber a-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile a-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, but less for the ...

2009-01-01

115

A relativistic mixing-layer model for jets in low-luminosity radio galaxies  

CERN Document Server

We present an analytical model for jets in Fanaroff & Riley Class I (FRI) radio galaxies, in which an initially laminar, relativistic flow is surrounded by a shear layer. We apply the appropriate conservation laws to constrain the jet parameters, starting the model where the radio emission is observed to brighten abruptly. We assume that the laminar flow fills the jet there and that pressure balance with the surroundings is maintained from that point outwards. Entrainment continuously injects new material into the jet and forms a shear layer, which contains material from both the environment and the laminar core. The shear layer expands rapidly with distance until finally the core disappears, and all of the material is mixed into the shear layer. Beyond this point, the shear layer expands in a cone and decelerates smoothly. We apply our model to the well-observed FRI source 3C31 and show that there ...

2009-01-01

116

Similarity between the primary and secondary air-assisted liquid jet breakup mechanism  

CERN Document Server

we report an ultrafast synchrotron x-ray phase contrast imaging study of the primary breakup mechanism of a coaxial air-assisted water jet. We demonstrate that there exist great similarities in the phenomenology of primary breakup with that of the secondary breakup. Especially, a membrane-mediated breakup mechanism dominates the breakup process for a wide range of air speeds. This finding reveals the intrinsic connections of these two breakup regimes and has deep implications on the unified theoretical approach in treating the breakup mechanism of high speed liquid jet.

2007-01-01

117

Operation of a high temperature ion source at the helium-jet on-line isotope separator facility HELIOS  

Energy Technology Data Exchange (ETDEWEB)

The performance of a high temperature ion source coupled to a helium gas-jet transport system for an efficient mass separation of neutron-rich alkaline earth and lanthanide isotopes is reported and the results of overall efficiency measurements using different cluster materials in the gas-jet are given. A fast, microprocessor controlled tape transport system for ..gamma..-spectroscopic studies on short-lived isotopes is described. Some results on the decay of 3.8sub(-s) /sup 152/Pr are presented. (orig.).

1985-02-01

118

Operation of a high temperature ion source at the helium-jet on-line isotope separator facility HELIOS  

Energy Technology Data Exchange (ETDEWEB)

The performance of a high temperature ion source coupled to a helium gas-jet transport system for an efficient mass separation of neutron-rich alkaline earth and lanthanide isotopes is reported and the results of overall efficiency measurements using different cluster materials in the gas-jet are given. A fast, microprocessor controlled tape transport system for ..gamma..-spectroscopic studies on short-lived isotopes is described. Some results on the decay of 3.8sub(-s) /sup 152/Pr are presented.

1985-02-01

119

Dependence of thermal plasma jet temperature on discharge power and gas flow rate  

International Nuclear Information System (INIS)

With the help of heat balance equation and high temperature thermodynamic function, the calibration relation of jet temperature with discharge power, gas flow rate was obtained for nitrogen thermal plasma. It was shown that the results were agreed with the principle of similarity. The jet temperature was a function of Peff/f, instead of a general two variables function of Peff and f, which were effective discharge power and working gas flow rate, respectively. A related discussion has been given; it will be referable to thermal plasma applications. (authors)

2008-03-01

120

Convective heat transfer under unsteady impinging jets: the effect of the shape of the unsteadiness  

Science.gov (United States)

Unsteady impinging jets are systematically controlled with respect to their time dependence in order to investigate the influence of unsteadiness on the heat transfer performance. This is achieved by a special mass flow control device, which allows almost arbitrary shapes of unsteadiness to be imposed onto the impinging jet. Three different standard signals (sinusoidal, triangular, rectangular) and two specially designed signals are applied and their influence on heat transfer is determined in terms of an enhancement factor. Heat transfer augmentation up to 30% was found and could be physically explained with the help of PIV and hot-wire measurements of the flow field.

2009-10-01

121

The sup(187m)Ir isomer state and its decay scheme  

International Nuclear Information System (INIS)

... beta spectrometers comparative evaluations data decay electrons

125

Wing-surface-jet interaction characteristics of an upper-surface ...  

Science.gov (United States)

Engine flow simulation was provided by four separately mounted air ejectors connected to a high-pressure air supply. The engine nacelle center lines were ...

126

View Record - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jan 13, 2011 ... This 360-degree mosaic of images from the navigation camera on ... The Radiation Assessment Detector, shown prior to its September 2010 ...

127

USDA Blog » 2009 » October  

Science.gov (United States)

or third generation fuels. These are biofuels that can directly substitute for gasoline, jet fuel, and diesel. Today more than 9 billion gallons of biofuels are produced annually...

2011-10-07

128

Time Characterization of High Density Gas Jet from a Pulsed Supersonic Nozzle via Laser Produced Plasma  

International Nuclear Information System (INIS)

A high-density gas jet supersonic nozzle is reported in this paper. The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respectively. The jitter time of the nozzle is within 10 ?s with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle, the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation, which reveals the existence of the gas jet and the relative gas density evolving with time. Consequently the gas density is estimated to be well above 1019 cm-3, compared with theoretical simulations from the nozzle parameters.

2006-07-01

129

The Nuclear Outflow in NGC 2110  

CERN Document Server

We present a HST/STIS spectroscopic and optical/radio imaging study of the Seyfert NGC 2110 aiming to measure the dynamics and understand the nature of the nuclear outflow in the galaxy. Previous HST studies have revealed the presence of a linear structure in the Narrow-Line Region (NLR) aligned with the radio jet. We show that this structure is strongly accelerated, probably by the jet, but is unlikely to be entrained in the jet flow. The ionisation properties of this structure are consistent with photoionisation of dusty, dense gas by the active nucleus. We present a plausible geometrical model for the NLR, bringing together various components of the nuclear environment of the galaxy. We highlight the importance of the circum-nuclear disc in determining the appearance of the emission line gas and the morphology of the jet. From the dynamics of the emission line gas, we place constraints on the ...

2010-01-01

130

State-of-the-Art in Improved Parts Programming for ...  

Science.gov (United States)

... ai jets used for chip removal. Control is normally effectd through the use of miscellaneous function M Codes on the postprocessor NC output. ...

1976-10-01

131

Space Images - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jan 18, 2011 ... The Radiation Assessment Detector, shown prior to its September 2010 ... This 360-degree panorama shows the vista from the location where ...

132

Smoothing of laser energy deposition by gas jets  

International Nuclear Information System (INIS)

Smoothing of laser beam non-uniformities using gas jets has been studied. The experiment has been performed with the PALS (Prague Asterix Laser System) laser working at 0.44 ?m with an intensity of about 1015 W/cm2. The laser beam has been split in two by a prism thus creating an artificial large-scale non-uniformity (? 90 ?m). We recorded time resolved and static images of laser-gas jet interaction with and without an Al target. Multi 1-dimensional and 2-dimensional simulations show that such interaction acts redistributing the over-intensities over larger surface. This effect has to be attributed to ionization processes with consequent laser beam refraction. Results show that Argon gas jet produces a strong refraction of the laser beam thus strongly reducing the initial two spots separation. (authors)

2009-08-01

133

RESEARCH MEMORANDUM - NASA Technical Report Server (NTRS)  

Science.gov (United States)

lytical Comparison of Turbine-Blade Cooling System Designed for a. TurboJet Engine Operat- at Supersonic Speed and Altitude. I1 -. Air-C~Oling Systems. ...

134

Profiles - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jun 30, 2003 ... He graduated from training with top honors and served as a parachute rigger and paratrooper for the 82nd airborne division at Fort Bragg, ...

135

Production of Jet Fuels from Coal-Derived Liquids. Volume 12. ...  

Science.gov (United States)

... The phenol and cresylic acid stream is flashed in a thin film evaporator over a concentrated sulfuric acid mixture to remove pyridine type substances ...

1989-12-01

136

PLASMA JET WELDING, COATING, AND CUTTING: AN ...  

Science.gov (United States)

... 31. New electric forming methods offer potentials for light metals; magnetic forming and plasma forming. ... 3, 25 Magnetic Forming ..... ...

1963-02-01

137

Opposed jet diffusion flames of nitrogen-diluted hydrogen vs air - Axial LDA and CARS surveys; fuel/air rates at extinction  

Science.gov (United States)

An experimental study of H-air counterflow diffusion flames (CFDFs) is reported. Coaxial tubular

1989-01-01

138
139

Numerical simulations of nucleate boiling in impinging jets: Applications in power electronics cooling  

Energy Technology Data Exchange (ETDEWEB)

Boiling jet impingement cooling is currently being explored to cool power electronics components. In hybrid vehicles, inverters are used for DC-AC conversion. These inverters involve a number of insulated-gate bipolar transistors (IGBTs), which are used as on/off switches. The heat dissipated in these transistors can result in heat fluxes of up to 200 W/cm{sup 2}, which makes the thermal management problem quite important. In this paper, turbulent jet impingement involving nucleate boiling is explored numerically. The framework for these computations is the CFD code FLUENT. For nucleate boiling, the Eulerian multiphase model is used. The numerical results for boiling water and R113 jets (submerged) are validated against existing experimental data in the literature. Some representative IGBT package simulations that use R134a as the cooling fluid are also presented. (author)

2008-01-15

140

Non-Intrusive, Laser-Based Imaging of Jet-A Fuel Injection and Combustion Species in High Pressure, Subsonic Flows  

Science.gov (United States)

The emphasis of combustion research efforts at NASA Glenn Research Center (GRC) is on collaborating

2000-01-01

141

NASA Jet Propulsion Laboratory - Lecture series  

Science.gov (United States)

A Self-Powered Underwater Robot for Ocean Exploration and Beyond ... first unmanned underwater vehicle (UUV) that is completely powered by renewable energy . ...

142

NASA - Spitzer Sees Spider Web of Stars  

Science.gov (United States)

star formation. To either side of the center, a small bar of dust and gas is helping to fuel the new stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the...

2011-07-20

143

NASA - A Cosmic Inkblot Test  

Science.gov (United States)

material may survive intact and mix back into interstellar gas clouds, helping to fuel the next generation of stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif.,...

2011-08-10

144

Live Web Chat: Earthquakes - How, Where and Why? - NASA Jet ...  

Science.gov (United States)

Mar 2, 2010 ... The NASA/JPL Education Office works with educators -- both classroom teachers and informal educators -- to provide tools, resources and ...

145

Jet flow analysis of liquid poison injection in a CANDU reactor using source term  

Energy Technology Data Exchange (ETDEWEB)

For the performance analysis of Canadian deuterium uranium (CANDU) reactor shutdown system number 2 (SDS2), a computational fluid dynamics model of poison jet flow has been developed to estimate the flow field and poison concentration formed inside the CANDU reactor calandria. As the ratio of calandria shell radius over injection nozzle hole diameter is so large (1055), it is impractical to develop a full-size model encompassing the whole calandria shell. In order to reduce the model to a manageable size, a quarter of one-pitch length segment of the shell was modeled using symmetric nature of the jet; and the injected jet was treated as a source term to avoid the modeling difficulty caused by the big difference of the hole sizes. For the analysis of an actual CANDU-6 SDS2 poison injection, the grid structure was determined based on the results of two-dimensional real- and source-jet simulations. The ...

2001-01-01

146

Jet Noise Modeling for Suppressed and Unsuppressed Aircraft in - NASA  

Science.gov (United States)

Mechanisms, AGARD Conference Proceedings No. 131, 1974, Paper No. 11. ... Olsen, W. and Karchmer, A., Lip Noise Generated by Flow Separation From Nozzle ...

147

Integrated coke, asphalt and jet fuel production process and apparatus  

Science.gov (United States)

A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

1991-01-01

148

Infrared Thermometer - NASA Spinoff  

Science.gov (United States)

May 1, 2011 ... Abstract: Diatek Corporation, San Diego, CA and the Jet Propulsion Lab developed the Diatek Model 7000 aural thermometer which weighs ...

149

Greenversations » 2009 » October  

Science.gov (United States)

this, however, was a real environmental threat since various drums containing jet fuel, Bunker C, diesel and other petroleum derivatives were on fire. The CAPECO...

2011-10-07

150

GHG Inventories & Forecasts: National Inventories and Forecasts...  

Science.gov (United States)

of different transportation fuels (e.g., gasoline, diesel fuel, aviation gasoline, jet fuel, residual fuel oil). Subsequent calculations are performed to estimate the share...

2011-08-26

151

Frequent Questions - Emissions | Climate Change | U.S. EPA  

Science.gov (United States)

activities, including the combustion of diesel fuel in heavy-duty vehicles and jet fuel in aircrafts. Current details on emissions from the transportation and other...

2011-04-14

152

Force Required to Detach Conidia of Helminthosporium maydis  

UK PubMed Central (United Kingdom)

The force required to break the conidium-conidiophore attachment in Helminthosporium maydis was measured by centrifugation and by a small jet of air. The force which removed half the...Full Text Available

1975-01-01

153

Fifty years of jet in cross flow research  

Science.gov (United States)

The jet in cross flow (JICF) is a basic flowfield which is relevant to a wide variety of applications which are described to provide context for JICF investigations. Material consistent with the scope of topics presented at the 72nd AGARD Fluid Dynamics Panel Meeting and Symposium on Computational and Experimental Assessment of Jets in Cross Flow on 19-22 April 1993 in Winchester, U.K. is summarized. The JICF research was divided into three time periods: (1) early research - up to 1970, (2) research during the 1970's, and (3) research since 1980. The following areas of experimental activity are discussed; the definition of an effective correlation parameter; the jet flowfield including the jet trajectories, cross-section shape, and jet induced pressures; the effects of jet deflection angle, nozzle shape, pressure ratio, velocity decay, and temperature; and the ...

1993-11-01

154

FR Doc 2010-30296  

Science.gov (United States)

cellulosic biofuel volumes for consumption as transportation fuel, heating oil, or jet fuel in the U.S. in 2011. We also evaluated the production and import potential for...

2010-12-08

155

FR Doc 2010-24310  

Science.gov (United States)

and used to reduce or replace petroleum-based transportation fuel, heating oil or jet fuel). In addition, this rule includes a new regulatory provision establishing a...

2010-09-27

156

Does Your Class Have Questions About Earthquakes? - NASA Jet ...  

Science.gov (United States)

Mar 15, 2011 ... The NASA/JPL Education Office works with educators -- both classroom teachers and informal educators -- to provide tools, resources and ...

157

Bioremediation  

Science.gov (United States)

from a military fuel storage facility released about 80,000 gallons of kerosine-based jet fuel. Immediate and extensive recovery measures managed to contain the spill, but...

2011-10-08

158

Bioremediation  

Science.gov (United States)

from a military fuel storage facility released about 80,000 gallons of kerosine-based jet fuel. Immediate and extensive recovery measures managed to contain the spill, but...

2011-08-27

159

Attendees - MEPAG - NASA  

Science.gov (United States)

Barlow, Nadine Northern Arizona University, Flagstaff, AZ. 10. Barker, Don NASA Johnson Space Center, TX. 11. Beaty, David NASA Jet Propulsion Laboratory, ...

160

Application of Synthetic Jets to Reduce Stator Flow Separation in a ...  

Science.gov (United States)

Surface pressure measurements at mid span indicate that flow separation begins near ..... Turbomachinery Flows, AGARD Propulsion Energetics Panel, 1998. ...

161

A Great Day to Go Flying  

Science.gov (United States)

but one test point on the flight cards was achieved before we hit our "bingo," or minimal fuel remaining, and we had to land. The radar was developed by NASA's Jet Propulsion...

2011-10-07

162

49 CFR 130.11 - Communication requirements.  

Science.gov (United States)

...identified as oil when the shipment document accurately describes the material as: aviation fuel, diesel fuel, fuel oil, gasoline, jet fuel, kerosene, motor fuel, or...

2010-10-01

163

--No Title--  

Science.gov (United States)

Air Show. The exhibit will feature 16 fuel companies showcasing cutting-edge alternative jet fuel technologies. In addition to individual company exhibits, the Showcase will...

2011-08-28

164

+ September 2006 - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Post-drive imaging included 360-degree view by the navigation camera and .... Sol 938: Opportunity completed another assessment of the clarity of the sky. ...

165

The Generalized Quantization Schemes for Games and its Application to Quantum Information  

CERN Document Server

Theory of quantum games is relatively new to the literature and its applications to various areas of research are being explored. It is a novel interpretation of strategies and decisions in quantum domain. In the earlier work on quantum games considerable attention was given to the resolution of dilemmas present in corresponding classical games. Two separate quantum schemes were presented by Eisert et al. and Marinatto and Weber to resolve dilemmas in Prisoners' Dilemma and Battle of Sexes games respectively. However for the latter scheme it was argued that dilemma was not resolved. We have modified the quantization scheme of Marinatto and Weber to resolve the dilemma. We have developed a generalized quantization scheme for two person non-zero sum games which reduces to the existing schemes under certain conditions. Applications of this generalized quantization ...

2010-01-01

166

Ramp-rate sensitivity of SSC dipole magnet prototypes  

Energy Technology Data Exchange (ETDEWEB)

One of the major achievements of the magnet R&D program for the Superconducting Super Collider (SSC) is the fabrication and test of a series of 20 5-cm aperture, 15-m long dipole magnet prototypes. The ramp rate sensitivity of these magnets appears to fall in at least two categories that can be correlated to the manufacturer and production batch of the strands used for the inner-coil cables. The first category, referred to as type-A, is characterized by a strong quench current degradation at high ramp rates, usually accompanied by large distortions of the multipole fields and large energy losses. The second category, referred to as type-B, is characterized by a sudden drop of quench current at low ramp rates, followed by a much milder degradation at larger rates. The multipole fields of the type-B magnets show little ramp-rate sensitivity, and the energy losses are smaller than for the type-A ...

1994-07-01

167

Merged-beams energy-loss technique for electron-ion excitation: Absolute total cross sections for O"5"+(2s#->#2p)  

International Nuclear Information System (INIS)

A merged-beams electron-energy-loss technique is described, by which absolute cross sections can be measured for near-threshold electron-impact excitation of multipy charged ions. Results are reported here for absolute total electron-impact excitation cross sections for the O"5"+(2s#->#2p) transition from below threshold to 1.6 eV above threshold. The experimental data are in good agremeent with a seven-state close-coupling calculation throughout the energy range of the experiment. Results agree with calculations showing that more than 90% of the electrons causing excitation are ejected in the backward direction in the center-of-mass frame. This backscattering is shown in both quantum-mechanical and semiclassical calculations. Evidence is observed for high-lying metastable autoionizing states with a lifetime of approximately 0.9 #mu#s which are made to ionize by electron impact.

168

How epitaxial are Pd/sub 2/Si-Si interfaces  

Energy Technology Data Exchange (ETDEWEB)

Pd/sub 2/Si layers produced by evaporation or sputtering onto silicon substrates were examined by high resolution electron microscopy, microdiffraction, X-ray, energy loss and Auger spectroscopy. The Si-Pd/sub 2/Si interfaces produced by evaporation were in all cases rougher and more polycrystalline than those produced by sputtering. X-ray microanalysis showed the predictable variation in palladium distribution across the interface but quantification did not produce the expected palladium-to-silicon ratios, primarily because of probe broadening and X-ray-induced fluorescence. Energy loss spectra showed plasmon energy shifts and changes in Si L edge shape due to bond formation with palladium. Auger data provided evidence for a small amount of oxygen at the Si-Pd/sub 2/Si interface. Electrical measurements of the ideality factor for Schottky barriers made from the materials produced higher values for the ...

1983-06-17

169

Excitation cross sections for the ns "2S#->#np "2P resonance transitions in Mg"+ (n=3) and Zn"+ (n=4) using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Electron-excitation cross sections are reported for the 3s "2S#->#3p "2P(h,k) resonance transition in Mg"+ at energies from threshold (4.43 eV) to approximately 9 times threshold (40.0 eV). The electron-energy-loss merged-beams technique used in these measurements is described in detail. In addition, the method of separating contributions of the elastically scattered (Coulomb) and the inelastically scattered electrons in the present Mg"+ case and previously reported Zn"+ results [Phys. Rev. Lett. 67, 30 (1991)] is described. Comparisons in the experimental energy range are made for Mg"+ with the two five-state close-coupling theoretical calculations carried out herein, and with other published close-coupling, distorted-wave, and semiempirical calculations. The present Mg"+ cross sections and Zn"+ cross sections from earlier measurements are tabulated.

170

Electron-impact excitation of multiply-charged ions using energy loss in merged beams: e+Si"3"+(3s"2S_1_/_2)#->#e+Si"3"+(3p"2P_1_/_2_,_3_/_2)  

International Nuclear Information System (INIS)

For the first time absolute total cross sections for electron-impact excitation of a multiply-charged ion have been measured using an electron-energy-loss technique. Measurements were made near threshold for the process e + Si"3"+(3s"2S_1_/_2) #-># e+Si"3"+(3p"2P_1_/_2_,_3_/_2)-8.88 eV. The 10"-"1"5 cm"2 measured cross section agrees with results of 7-state close coupling calculations to better than the #+-#20% (90% CL) total uncertainty of the measurements. Convoluting the theoretical curve with a Gaussian energy distribution indicates an energy width of 0.15 < or approx. #DELTA#E < or approx. 0.20 eV. (orig.).

171

Determination of the thickness and density of the ion bombardment induced altered layer in SiC by means of reflection electron energy loss study  

International Nuclear Information System (INIS)

The steady state surfaces of ion bombarded 3C-, 4H- and 6H-SiC samples were studied by means of reflected electron energy loss spectroscopy (REELS). The REELS exhibit a well-defined loss peak in the region of about 20 eV. The position of the maximum of the loss peak depends on the bombarding ion energy (decreasing with increasing ion energy), and on the primary electron beam energy (increasing with increasing primary energy). This behavior can be explained if we suppose that the plasmon energy in the altered layer (produced by ion bombardment) is different from that of the unaltered bulk. In this case the measured loss peak is the sum of two overlapping plasmon peaks. With modeling the system as a homogeneous altered layer and a homogeneous unaltered substrate the plasmon energy in the altered layer was derived to be 19.8 eV. The large change of the plasmon energy with respect to the bulk value of 23 eV is explained by a thin low density ...

2005-12-15

172

AC loss measurements of model and full size 50mm SSC collider dipole magnets at Fermilab  

Energy Technology Data Exchange (ETDEWEB)

Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500, to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar magnet types agree to within experimental error, while eddy current losses correlate strongly with the observed ...

1992-09-01

173

The full order weak schemes of the Langevin simulations  

Energy Technology Data Exchange (ETDEWEB)

New partial differential equations (PDEs) for the full order weak schemes of the Langevin simulations are formulated. They are solved recursively in full order series solutions with respect to {radical}(t) (the full order weak Taylor schemes). Arbitrariness involved in the solutions is analyzed and clarified in detail. Specific solutions within some orders are presented as examples of the weak Taylor schemes. These PDEs and their solutions will serve for further developments of efficient higher order Runge-Kutta-like schemes. The similar formulation is possible for the imaginary time Hamiltonian evolution kernels as well. (orig.). 9 refs.

1998-04-01

174

Feasibility study on scheme of disposing spent guide tubes at Daya Bay nuclear power plant  

International Nuclear Information System (INIS)

The author describes feasibility study on the scheme of disposing spent guide tubes at Daya Bay nuclear power plant, including scheme selection, packing cask design, disposal operation and technological process, budget estimation and safety evaluation. The research results show that the new scheme is feasible on technology, and reasonable on budget. If the scheme is adopted to dispose the spent guide tubes at Daya Bay nuclear power station, it can not only save large funds, but also accumulate experience on disposing non-compressible low and intermediate level solid radioactive wastes produced at nuclear power station for the country

1998-12-01

175

Capacity of a Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties  

Science.gov (United States)

We analyse the capacity of a simultaneous quantum secure direct communication scheme between the central party and other M parties via M+1-particle GHZ states and swapping quantum entanglement. It is shown that the encoding scheme should be secret if other M parties wants to transmit M+1 bit classical messages to the centre party secretly. However, when the encoding scheme is announced publicly, we prove that the capacity of the scheme in transmitting the secret messages is 2 bits, no matter how large M is.

2006-10-01

176

Superconducting magnetic and inertial energy pulsed power systems  

International Nuclear Information System (INIS)

Superconducting magnetic and inertial energy pulsed power systems are being developed for future theta-pinch, Tokamak, and laser fusion applications. The short term requirements for these applications are discussed along with present day accomplishments. Areas requiring a research and development effort are examined in detail. Subjects discussed include stresses, energy loss factors, conductor metallurgy, cryogenic requirements, and electrical limitations of superconducting magnetic storage systems; costs, applications, and present technology of homopolar systems; and switching problems associated with both systems.

1975-07-15

177

Study of physical properties of protons and "1"2C ions in medical application  

International Nuclear Information System (INIS)

Depending on their unique physical properties, proton and heavy ions have taken an irreplaceable role in modern means of tumor treatment. One-step process and two-step process physical models were employed to explain the mechanism of ion energy loss. The transport process of proton and "1"2C in water was simulated by Geant4 toolkit to study the physical properties of ion beam. The calculation results were discussed, which showed the advantages and disadvantages of proton and "1"2C in the medical application. (authors)

2009-06-01

178

Smart Acquisition EELS  

Energy Technology Data Exchange (ETDEWEB)

Electron energy loss (EEL) spectroscopy and high angle annular dark field (HAADF) imaging in aberration-corrected electron microscopes are powerful techniques to determine the chemical composition and structure of materials at atomic resolution. We have implemented Smart Acquisition, a flexible system of scanning transmission electron microsocpy (STEM) beam position control and EELS collection, on two aberration-corrected dedicated cold field emission gun (FEG) STEMs located at SuperSTEM, Daresbury Laboratory. This allows the collection of EEL spectra from spatially defined areas with a much lower electron dose possible than existing techniques such as spectrum imaging.

2010-07-01

179

Methods and instruments for nondestructive testing of the anisotropy of the magnetic properties of ferromagnetic sheet materials (review)  

Energy Technology Data Exchange (ETDEWEB)

This review of methods and designs of transducers for nondestructive determination of the magnitude and nature of the anisotropy of magnetic properties (permeability, induction, coercive force, energy loss due to magnetization reversal) in local portions of ferromagnetic sheet and, in some cases, in individual parts of products. The need to measure the anisotropy is considered for two angles: for the case when the anisotropy is due to the crystallographic texture and determines the main operating characteristics of widely used sheet such as electrical steel and automobile body sheet, and for crystallographically isotropic materials, in which the anisotropy of magnetic properties as a result of mechanical stresses is a measure for determining the internal stresses.

1995-04-01

180

Leak detection on petroleum pipelines  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a unique method, currently under evaluation, that can continuously track pipeline operation providing essentially instantaneous responses to leaks or ruptures without causing a pressure drop or energy loss. Using the highly linear characteristics of a very accurate and repeatable meter and then correlating it to a second identical unit, a dynamic leak detection system is planned that can be retrofitted on existing pipelines without a major construction effort nor destroying the integrity of the existing transmission line. Initial tests performed on a crude oil transmission line verified the equipment's performance and established that the repeatability limits are sufficient to continue development of the concept.

1984-04-01

181

Hydrodynamics of swirling flow in a circular tube with sudden increase in cross-section and of the flow through a Borda mouthpiece  

Energy Technology Data Exchange (ETDEWEB)

By applying the mass, momentum, and angular momentum conservation laws and the maximum flow rate principle to swirling, effectively inviscid, incompressible flows in a circular tube with a sudden expansion and the direct-flow and reversed-flow Borda mouthpieces the dependence of the flow rate coefficient and mechanical energy losses on the radius ratio and nondimensional circulation is obtained. Several calculating approaches with potential and helical motion are introduced and investigated. In the case of helical motion, as the swirl decreases the axial core of the flow is found to close with a sudden change of the flow parameters.

1994-11-01

182

Employing exergy-optimized pin fins in the design of an absorber in a solar air heater  

Energy Technology Data Exchange (ETDEWEB)

Fins serve as heat transfer augmentation features in solar air heaters; however, they increase pressure drop in flow channels. Pin fins are relatively good heat transfer augmentation features with superior aerodynamic performance, and as a result find application in some solar air heaters. The exergy optimization method is employed in sizing the pin fin. Results indicate that high efficiency of the optimized fin improves the heat absorption and dissipation potential of a solar air heater. With optimum fin efficiency and superior absorptive coating quality, useful energy losses can be minimized. Some important observations pertinent in design are made. (author)

2010-02-15

183

A new calculation of the cosmic-ray antiproton spectrum in the Galaxy and heliospheric modulation effects on this spectrum using a drift plus wavy current sheet model  

Energy Technology Data Exchange (ETDEWEB)

The expected interstellar antiproton spectrum arising from cosmic-ray interactions in the Galaxy is recalculated, and the modulation of both antiprotons and protons is calculated using a two-dimensional modulation model incorporating gradient and curvature drifts and a wavy current sheet as well as the usual diffusion, convection, and energy-loss effects. Significant differences in the antiproton/proton ratio for different solar magnetic field polarities are predicted as well as a 'low-energy' component for antiprotons below about 1 GeV. 28 refs.

1989-09-01

184

Understanding and predicting soot generation in turbulent non-premixed jet flames.  

Energy Technology Data Exchange (ETDEWEB)

This report documents the results of a project funded by DoD's Strategic Environmental Research and Development Program (SERDP) on the science behind development of predictive models for soot emission from gas turbine engines. Measurements of soot formation were performed in laminar flat premixed flames and turbulent non-premixed jet flames at 1 atm pressure and in turbulent liquid spray flames under representative conditions for takeoff in a gas turbine engine. The laminar flames and open jet flames used both ethylene and a prevaporized JP-8 surrogate fuel composed of n-dodecane and m-xylene. The pressurized turbulent jet flame measurements used the JP-8 surrogate fuel and compared its combustion and sooting characteristics to a world-average JP-8 fuel sample. The pressurized jet flame measurements demonstrated that the surrogate was representative of JP-8, with a somewhat higher tendency to ...

2010-10-01

185

Software framework and jet energy scale calibration in the ATLAS experiment; Environnement logiciel et etalonnage de l'echelle en energie des jets dans l'experience ATLAS  

Energy Technology Data Exchange (ETDEWEB)

This thesis presents the work achieved to instrument the ATLAS software framework, ATHENA, with a library of tools and utensils for the physics analysis as well as the extraction of the jet energy scale using physics events (in-situ calibration). The software part presents the various components of the ATHENA framework which handles the simulated and reconstructed data flow as well as the different stages of this process, before and during the data taking. The building of a library of tools easing the reconstruction of physics objects, their association with Monte-Carlo particles and their API is then explained. The need for common language and collaboration-wide utensils is emphasised as it allows to share the workload of validating these tools and to get reproducible physics results. The analysis part deals with the implementation of a light jet energy scale calibration algorithm within the C++ framework. This calibration algorithm makes use ...

2006-07-01

186

Remote participation technical infrastructure for the JET facilities under EFDA  

Energy Technology Data Exchange (ETDEWEB)

The new collaborative exploitation of the JET Facilities requires suitable technical tools and infrastructure measures to enable the Remote Participation of scientists from all European Fusion labs. Such measures are being gradually introduced. They comprise of a toolkit for Remote Data Access, Remote Computer Access and for teleconferencing, and of infrastructure measures that address network connectivity, network security, shared documentation and technical support.

2001-10-01

187

PIV measurements of flow structures in a spray dryer  

DEFF Research Database (Denmark)

Stereoscopic Particle Image Velocimetry (PIV) measurements are made in horizontal planes in a simplified scale model of a spray dryer using water as fluid. The sample rate was sufficient to resolve phenomena at lower frequencies. Data reveal asymmetric velocity fields in both mean fields and dynamics. Data were analysed using Proper Orthogonal Decomposition (POD). An important periodic event is an elongation of the jet core cross section that results in a downstream displacement of the jet towards the chamber wall.

2011-01-01

188

Neutron detection techniques for plasma diagnostics at the Joint European Torus (JET)  

International Nuclear Information System (INIS)

The importance of neutron measurements both as a succinct measure of the progress to fusion ignition using the magnetic confinement route and also as a diagnostic of plasma conditions is discussed. The various neutron diagnostic systems that have been or are being constructed by AERE Harwell for JET are described. The properties to be measured by such diagnostics are clearly identified and some results obtained with the installed diagnostics during d-d plasmas are presented.

189

Concept of Plasma Spraying System for Solid Oxide Fuel Cell: Heating Studies of YSZ Particle in Plasma Jet  

International Nuclear Information System (INIS)

One of several methods to build YSZ electrolyte of SOFC is plasma spraying. This system heats particle to a melting point and then pushing them into target and forming a deposition. This paper presents heating studies of YSZ particle in plasma jet. By simple model it is shown that the required time such those YSZ particle with grain size of 50 ?m to be melt is around 12 x 10-4 second. (author)

2006-07-01

190

Analytical determination of the dimensions and evolution with current of the ion-emitting jet in liquid-metal ion sources  

Energy Technology Data Exchange (ETDEWEB)

The apex dimensions and length are calculated as a function of current for the ion-emitting jet in liquid-metal ion sources (LMIS). The results agree well with observations. Since the final expressions are analytical, they give more insight into the fundamental mechanisms involved than do numerical calculations. Some implications of the model are discussed concerning focused ion beam (FIB) systems employing LMIS. (author).

1991-12-14

191

Advanced thermally stable jet fuels: Technical progress report, October 1994--December 1994  

Science.gov (United States)

There are five tasks within this project on thermally stable coal-based jet fuels. Progress on each of the tasks is described. Task 1, Investigation of the quantitative degradation chemistry of fuels, has 5 subtasks which are described: Literature review on thermal stability of jet fuels; Pyrolytic and catalytic reactions of potential endothermic fuels: cis- and trans-decalin; Use of site specific {sup 13}C-labeling to examine the thermal stressing of 1-phenylhexane: A case study for the determination of reaction kinetics in complex fuel mixtures versus model compound studies; Estimation of critical temperatures of jet fuels; and Surface effects on deposit formation in a flow reactor system. Under Task 2, Investigation of incipient deposition, the subtask reported is Uncertainty analysis on growth and deposition of particles during heating of coal-derived aviation gas turbine fuels; under Task 3, Characterization of solid ...

1995-02-01

192

The jet-powered optical nebula of Cygnus X-1  

CERN Document Server

We present H-alpha and [O III] (5007 Angstroms) images of the nebula powered by the jet of the black hole candidate and microquasar Cygnus X-1, observed with the 2.5m Isaac Newton Telescope (INT). The ring-like structure is luminous in [O III] and there exists a thin outer shell with a high [O III] / H-alpha flux ratio. This outer shell probably originates in the collisionally excited atoms close to the front of the bow shock. Its presence indicates that the gas is shock excited as opposed to photoionised, supporting the jet-powered scenario. The shock velocity was previously constrained at 20 = 100 km/s (1 sigma confidence) based on a comparison of the observed [O III] / H-alpha ratio in the bow shock with a number of radiative shock models. From this we further constrain the time-averaged power of the jet: P_Jet = (4 - 14)*10^36 erg/s. The H-alpha flux behind the shock front is typically 4*10^-15 ...

2007-01-01

193

Plasma nitriding of substrate by using supersonic nitrogen plasma jet; Cho onsoku chisso plasma jet wo mochiita Ti kizai no plasma chikka  

Energy Technology Data Exchange (ETDEWEB)

Plasma nitriding of a Ti substrate is carried out under a low ambient pressure below 3kPa, and a plasma torch is prepared on a trial basis which is provided with a supersonic expansion nozzle considered to expand plasma jet optimally and to be effective for suppressing the occurrence of shock wave. The system used for the study is provided with a specimen holder having the function of adjusting the distance between the nozzle outlet and the substrate inside the vacuum chamber which is provided with a plasma torch in the flange member. The plasma torch is so structured that a supersonic expansion nozzle can be installed at the tip of the plasma torch. In this process wherein plasma jet is employed, hard nitrided layer can be formed by plasma irradiation for a short time even under such low pressure as less than 3kPa by setting adequate experimental conditions. It is made clear that the use of a supersonic nozzle corresponding to the internal ...

1997-07-01

194

Modification of the sheet resistance of ink jet printed polymer conducting films by changing the plastic substrate  

Energy Technology Data Exchange (ETDEWEB)

The ink jet printing technology is a relatively novel technique in development of organic electronic devices. The technique consists of working out depositions of organic layers by a piezo-based ink jet printer. In this work polymer conducting films deposited by ink jet printing technique on different plastic substrates has been demonstrated. The poly(3,4-ethylenedioxythiofene)/poly(4-styrenesulfonate) [PEDOT/PSS] and glycerol-modified PEDOT/PSS [G-PEDOT/PSS] were used like conducting inks to be applied on polyester and polyethylene terephthalate (PET) substrates. By means of the change of substrate associated to the deposition number or type of polymer ink used for printing of the conducting films, the sheet resistance can be modified. Such a behavior suggests that plastic substrate fulfills an important role for the changing of sheet resistance of the PEDOT/PSS and G-PEDOT/PSS films made by ink jet ...

2005-09-25

195

A new method of heat transfer augmentation by means of foreign gas jet impingement in liquid bath  

International Nuclear Information System (INIS)

The authors discuss a two-phase two-component experimental system developed to study enhancement of heat transfer from a vertical chip size heater to surrounding liquid (Freon 113 or Ethanol) due to air jet impingement. Heat transfer coefficient was measured as function of jet velocity, heat flux and the distance between exit of jet tube and heated surface. The injector was placed very close to the hot surface. It was found that the heat transfer was notably enhanced with foreign gas impingement, especially in the cases of small temperature differences between wall and coolant. In fact for higher jet velocities the heat transfer coefficients tended to infinite while the temperature differences between wall and coolant were zero. The heat transfer coefficients decreased with the increasing of heat flux. High-speed camera was used to study the behaviour of the gas bubbles which play very important role in ...

1985-10-01

196

Analysis of the role of the planetary boundary layer schemes during a severe convective storm  

Energy Technology Data Exchange (ETDEWEB)

The role played by planetary boundary layer (PBL) in the development and evolution of a severe convective storm is studied by means of meso-scale modeling and surface and upper air observations. The severe convective precipitation event that occurred on 14 September 1999 in the northeast of the Iberian Peninsula was simulated by means of the mesoscale model MM5 (version 3) using three different PBL schemes. The numerical results show a large impact of the PBL schemes on the precipitation fields associated to the convective storm. The schemes are based on different physical assumptions: the nonlocal first order medium-range forecast (MRF) and blackadar (BLA) scheme and the local, one-and-a-half order ETA scheme. Surface and radar observations are used to validate the model results. The comparison focuses on three aspects: the evolution, the spatial distribution and the 24-h ...

2004-07-01

197

Quantum secure direct communication scheme using a W state and teleportation  

International Nuclear Information System (INIS)

A theoretical scheme for quantum secure direct communication (QSDC) is proposed, where a three-qubit symmetric W state functions as a quantum channel. Two legitimate communicators can transmit their secret information by using quantum teleportation and local measurements.

2006-11-01

198

Quality control in laboratory investigations on Schistosoma mansoni on St Lucia, West Indies: a staff assessment scheme*  

UK PubMed Central (United Kingdom)

A method is described for the supervision of technicians engaged in microscopical screening of large numbers of stools for Schistosoma mansoni ova. The scheme presents graphically...Full Text Available

1978-01-01

199

Nuclear Data Sheets for A = 66  

International Nuclear Information System (INIS)

The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all isobars with mass number A = 66. The first level- scheme of "6"6As, from (HI,xn#gamma#), has been included in this evaluation.

2010-04-01

200

Microsoft Word - BN001CRC.docx  

Wastenet

Briefing Note November 2009 The Carbon Reduction Commitment (CRC) Energy Efficiency Scheme: UPDATE ...What is the CRC? ... The CRC is a mandatory emissions trading scheme that aims to deliver energy (and so

201

Investigation of the decay scheme of $sup 177$W by means of $gamma$-- $gamma$ coincidences  

Science.gov (United States)

The gamma spectrum and gamma - gamma coincidences of /sup 177/W were measured with a Ge(Li) detector. A level scheme was proposed for /sup 177/Ta. (tr-auth)

1973-08-01

202

Two-phase flow characteristic of inverted bubbly, slug and annular flow in post-critical heat flux region  

Energy Technology Data Exchange (ETDEWEB)

Inverted annular flow can be visualized as a liquid jet-like core surrounded by a vapor annulus. While many analytical and experimental studies of heat transfer in this regime have been performed, there is very little understanding of the basic hydrodynamics of the post-CHF flow field. However, a recent experimental study was done that was able to successfully investigate the effects of various steady-state inlet flow parameters on the post-CHF hydrodynamics of the film boiling of a single phase liquid jet. This study was carried out by means of a visual photographic analysis of an idealized single phase core inverted annular flow initial geometry (single phase liquid jet core surrounded by a coaxial annulus of gas). In order to extend this study, a subsequent flow visualization of an idealized two-phase core inverted annular flow geometry (two-phase central jet core, surrounded by a coaxial annulus of ...

1988-01-01

203

Production of jet fuel using heavy crude oil; Producao de combustiveis de aviacao a partir de petroleos pesados  

Energy Technology Data Exchange (ETDEWEB)

The production of heavy crude oils increased in the last years in the world. Crude oils with high density, viscosity, acidity and sulfur, nitrogen, metals and asphaltenes contents, by the others hand, low stability and low product quality. The challenger of many refiners is find solutions to refine the heavy crude oils, and produce fuels with certify quality, such as Jet Fuel. The principal aviation technique on the world work with gas turbines engines feted for jet fuel (JET A1). The quality specifications of this fuel are establish by International Norms: ASTM-1655, DEF STAN 91-91-3 (DERD 2494) and joint Fuelling System Check List. The world technologies to obtain jet fuel from mixtures of heavy crude oil with middle crude oils are: Atmospheric distillation, with a posterior hydrogenation and finally the additivation. Studies carried out have demonstrates that the Cubans heavy crude oils is ...

2004-07-01

204

Life Cycle Assessment of Potential Bio-jet Fuel Production in the United States.  

Science.gov (United States)

The objective of this paper is to reveal to what degree bio-based jet fuels (bio-jet) can reduce greenhouse gas (GHG) emissions from the US aviation sector. A model of the supply and demand chain of bio-jet involving farmers, bio-refineries, airlines, and policymakers is developed by considering factors that drive the decisions of actors (i.e. decision-makers and stakeholders) in the life cycle stages. Two kinds of feedstock are considered: oil-producing feedstock (i.e. camelina and algae) and lignocellulosic biomass (i.e. corn stover, switchgrass, and short rotation woody crops). By factoring in farmer/ feedstock producer and bio-refinery profitability requirements, land availability and suitability, as well as a time delay factor, a more realistic estimate of the level of bio-jet supply and emissions reduction can be developed under different oil price assumptions. Factors that drive ...

2011-09-29

205
206

Multigrid Particle-in-cell Simulations of Plasma Microturbulence  

Energy Technology Data Exchange (ETDEWEB)

A new scheme to accurately retain kinetic electron effects in particle-in-cell (PIC) simulations for the case of electrostatic drift waves is presented. The splitting scheme, which is based on exact separation between adiabatic and on adiabatic electron responses, is shown to yield more accurate linear growth rates than the standard df scheme. The linear and nonlinear elliptic problems that arise in the splitting scheme are solved using a multi-grid solver. The multi-grid particle-in-cell approach offers an attractive path, both from the physics and numerical points of view, to simulate kinetic electron dynamics in global toroidal plasmas.

2003-06-17

207

Isomer sup(187m)Ir and its decay scheme  

International Nuclear Information System (INIS)

... comparative evaluations energy-level transitions half-life internal conversion

1974-01-29

208

Investigation of W"1"7"7 decay scheme by #gamma##gamma#-coincidence method  

International Nuclear Information System (INIS)

... coincidence spectrometry decay excited states gamma spectra half-life

1973-01-29

209

A practical scheme for error control using feedback  

CERN Document Server

We describe a scheme for quantum error correction that employs feedback and weak measurement rather than the standard tools of projective measurement and fast controlled unitary gates. The advantage of this scheme over previous protocols (for example Ahn et. al, PRA, 65, 042301 (2001)), is that it requires little side processing while remaining robust to measurement inefficiency, and is therefore considerably more practical. We evaluate the performance of our scheme by simulating the correction of bit-flips. We also consider implementation in a solid-state quantum computation architecture and estimate the maximal error rate which could be corrected with current technology.

2004-01-01

211

Three-Party Simultaneous Quantum Secure Direct Communication Scheme with EPR Pairs  

Science.gov (United States)

We present a scheme for three-party simultaneous quantum secure direct communication by using EPR pairs. In the scheme, three legitimate parties can simultaneously exchange their secret messages. It is also proved to be secure against the intercept-and-resend attack, the disturbance attack and the entangled-and-measure attack.

2007-09-01

212

The enhancement of three-party simultaneous quantum secure direct communication scheme with EPR pairs  

Science.gov (United States)

Recently, Wang et al. proposed a three-party simultaneous quantum secure direct communication (3P-SQSDC) scheme with EPR pairs, which enables three involved parties to exchange their secret messages simultaneously by using an EPR pair. This work proposed an enhancement on Wang et al.'s scheme. With the enhancement, the communications in the improved 3P-SQSDC can be paralleled and thus improves the protocol efficiency.

2011-01-01

213

Quantum Discrete Fourier Transform in an Ion Trap System  

International Nuclear Information System (INIS)

We propose two schemes for the implementation of quantum discrete Fourier transform in the ion trap system. In each scheme we design a tunable two-qubit phase gate as the main ingredient. The experimental implementation of the schemes would be an important step toward complex quantum computation in the ion trap system.

2007-06-15

214

Preparation of Cluster States for Many Atoms in Cavity QED  

International Nuclear Information System (INIS)

We propose a scheme for the generation of the cluster states for many atoms in cavity QED. In our scheme, the atoms are sent through nonresonant cavity fields in the vacuum states. The cavity fields are only virtually excited and no quantum information will be transferred from the atoms to the cavity fields. The advantage is that the cavities are suppressed during the procedure. The scheme can also be generalized to the ion trap system.

2007-07-15

215

Enhancing participation in kitchen waste collections  

Wastenet

...food waste recycling schemes; (3) Six in-depth site visits to authorities operating collection schemes in order to capture information on scheme design, operational issues and factors affecting public engagement. The case study areas were: Bexley, Cambridge, Fenland, Hackney, Taunton Deane and Weymouth & Portland;...

216

A nonlinear positive method for solving the transport equation on course meshes  

Energy Technology Data Exchange (ETDEWEB)

A new nonlinear S{sub n} transport differencing scheme for slab geometry is presented that is fourth order accurate for small meshes and is strictly positive. The new scheme has been coded into the existing ONELD code and tested. Numerical results to demonstrate the accuracy and positivity of this new scheme are presented.

1994-02-01

217

A new sixth-order scheme for nonlinear equations  

British Library Electronic Table of Contents (United Kingdom)

In this paper we present a new efficient sixth-order scheme for nonlinear equations. The method is compared to several members of the family of methods developed by Neta (1979) [B. Neta, A sixth-order family of methods for nonlinear equations, Int. J. Comput. Math. 7 (1979) 157-161]. It is shown that the new method is an improvement over this well known scheme.

2012-01-01

218

The new JET phased ICRH array: first experiments and modelling  

Energy Technology Data Exchange (ETDEWEB)

New ICRH antennas on JET were designed to couple to the new JET divertor plasma configurations and to improve the Fast Wave Current Drive (FWCD) capabilities. The A2 antenna consists of 4 straps whose currents can be phased at arbitrary angles. The real time automatic tuning acts on frequency, line length (line phase shifters) and stub length. Provision is made for the coupling resistance/plasma position feedback to accommodate the fast changes in antenna loading. The first coupling, tuning and heating results are reported in 0{pi}0{pi}, 0000 and 00{pi}{pi} phasing. A new antenna model is described, which was developed to simulate the measured antenna loading in terms of plasma parameters and to provide a starting point for the real time automatic tuning. 5 refs., 4 figs.

1994-07-01

219

THE RADIO JET INTERACTION IN NGC 5929: DIRECT DETECTION OF SHOCKED GAS  

International Nuclear Information System (INIS)

We report on the discovery of kinematic shock signatures associated with a localized radio jet interaction in the merging Seyfert galaxy NGC 5929. We explore the velocity-dependent ionization structure of the gas and find that low-ionization gas at the interaction site is significantly more disturbed than high-ionization gas, which we attribute to a local enhancement of shock ionization due to the influence of the jet. The characteristic width of the broad low-ionization emission is consistent with shock velocities predicted from the ionization conditions of the gas. We interpret the relative prominence of shocks to the high density of gas in the nuclear environment of the galaxy and place some constraints of their importance as feedback mechanisms in Seyferts.

2010-03-10

220

Remotely sensing of excavation cavity during mining  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method of hydraulically mining a surface of a mining location comprising: a. determining the dimensions of the surface of the mining location from a fixed point at the location; b. constructing at a second location remote from the mining location a visual representation of the surface form the determined dimensions of the mining location with respect to the fixed point; c. jetting water under high pressure against a selected area on the surface of the mining location; d. determining changes in the dimensions of the selected area of the surface of the mining location; e. reconstructing at the second location a new visual representation of the surface from the determined changes of the location during the jetting of the water; and f. redirecting the jetted water under high pressure utilizing data from the reconstructed visual representation.

1987-11-24

221

Jets and accretion processes in Active Galactic Nuclei further clues  

CERN Document Server

We present evidence in favour of a link between the luminosity radiatively dissipated in the central engine of radio-loud Active Galactic Nuclei and the kinetic power in their jets. This piece of evidence is based on the relation we find between the luminosity in broad emission lines and the kinetic power in pc-scale radio jets, for a sample of radio-loud quasars for which suitable data are available in the literature. We find that the ionizing luminosity and the kinetic one are of the same order of magnitude, suggesting that the processes responsible for them are somehow related. A strong magnetic field in equipartition with the radiation field could be responsible for regulating both processes. BL Lac objects seem to follow a similar behaviour, but with comparatively fainter broad line emission.

1996-01-01

222

Gamma-Ray Burst jet dynamics and their interaction with the progenitor star  

CERN Document Server

The association of at least some long gamma-ray bursts with type Ic supernova explosions has been established beyond reasonable doubt. Theoretically, the challenge is to explain the presence of a light hyper-relativistic flow propagating through a massive stellar core without losing those properties. We discuss the role of the jet-star interaction in shaping the properties of the outflow emerging on the surface of the star. We show that the nature of the inner engine is hidden from the observer for most of the evolution, well beyond the time of the jet breakout on the stellar surface. The discussion is based on analytical considerations as well as high resolution numerical simulations. Finally, the observational consequences of the scenario are addressed in light of the present capabilities.

2006-01-01

223

Experimental assessment of the velocity and temperature distribution in an indoor displacement ventilation jet  

British Library Electronic Table of Contents (United Kingdom)

Displacement Ventilation (DV) offers a great opportunity to improve indoor air quality while reducing the energy consumption compared to mixing ventilation. A frequent problem with displacement ventilation is however the draft discomfort caused by the cold air movement at foot level and excessive temperature difference between head and ankle. Despite numerous past studies, there is still a lack of detailed data regarding the velocity and temperature distribution inside DV jets. In this experimental study, measurements of the air velocity and temperature are performed in the DV jet produced by a flat wall-mounted DV diffuser, using a fine mesh focused on the 0.00-0.20 m height range. Two supply conditions are studied. Three planes of measurements are covered: the vertical longitudinal plane...

2012-01-01

224

U.S. Department Of Energy's nuclear engineering education research: highlights of recent and current research-II. 4. Studies of Forced-Convection Heat Transfer Augmentation in Large Containment Enclosures  

International Nuclear Information System (INIS)

This paper provides information on heat transfer enhancement due to jet mixing inside a cylindrical enclosure. The work addresses conservative heat transfer assumptions regarding mixing and condensation that have typically been incorporated into passive containment design analyses. The current research presents an interesting possibility for increasing decay heat removal of passive containment systems under combined natural and forced convection. Eliminating these conservative assumptions could provide the basis for a change of containment design and reduce the construction cost. It is found that the ratio of forced- and free convection Nusselt numbers can be predicted as a function of the Archimedes number and a correlated factor accounting for jet orientation and enclosure geometry. To use the small-scale tests for large containment design, scale-up methods and criteria are important for matching the key governing parameters and fluid ...

2001-06-17

225

Single-pole switching schemes for EHV transmission systems  

Energy Technology Data Exchange (ETDEWEB)

Recognizing that a high percentage of transmission-line faults are single-phase to earth and temporary in nature, provides the impetus for considering single-pole switching as a means to enhance the reliability of EHV transmission systems. The effectiveness of single-pole switching schemes is largely determined by the speed with which the secondary arcs extinguish, and hence allow system restoration. Simulation techniques that enable better prediction of the faulted-system response are of obvious importance to the design and assessment of the various single-pole switching scheme applications. In this thesis, digital methods are developed to enable the faulted response of EHV systems to be simulated for a variety of different single-pole switching schemes. These include conventional single-pole switching, the hybrid method of autoreclosure, the neutral switched reactor, and the High Speed Grounding Switch implementations. ...

1986-01-01

226

Microcrystalline-Si thin-film transistors formed by using palladium silicided source/drain contact electrode  

British Library Electronic Table of Contents (United Kingdom)

Microcrystalline-Si thin-film transistors (?C-Si TFTs) formed by using the source/drain contact electrode of self-aligned palladium silicide have been investigated. Both the self-aligned palladium silicided scheme and the previous top-gate staggered structure employ two-mask process steps for fabricating ?C-Si TFTs. However, the self-aligned palladium silicided scheme would cause better device characteristics than the top-gate staggered structure, primarily due to more carrier tunneling. For a gate length of 2 ?m, as compared to the top-gate staggered scheme, this silicided scheme can result in a 40% improvement of on-state current. In addition, as the gate length is reduced to 1 ?m, considerable short-channel effect is caused for both the device schemes.

2010-01-01

227

A Swarm Intelligence Based Scheme for Complete and Fault-tolerant Identification of a Dynamical Fractional Order Process  

CERN Document Server

System identification refers to estimation of process parameters and is a necessity in control theory. Physical systems usually have varying parameters. For such processes, accurate identification is particularly important. Online identification schemes are also needed for designing adaptive controllers. Real processes are usually of fractional order as opposed to the ideal integral order models. In this paper, we propose a simple and elegant scheme of estimating the parameters for such a fractional order process. A population of process models is generated and updated by particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. Results show that the proposed scheme offers a high degree of accuracy even when the observations are corrupted to a significant degree. Additional schemes to improve the accuracy still further are ...

2008-01-01

228

The propagation of relativistic heavy ions in multielement beam lines.  

Science.gov (United States)

We describe calculations of the energy loss, range, stopping power, multiple scattering, and other related properties of a high-energy heavy-ion beam at any one of a set of beam line elements. A beam line element (e.g., any beam modification, detection, or control device) is characterized by its thickness, areal density, aperture, and function. The loss of multiply scattered particles to any finite-aperture detector is calculated in the small-angle approximation, and the position of the Bragg peak, as given by particles stopping in the second of two ionization chambers used for Bragg curve measurements, is estimated. A general purpose computer program, PROPAGATE, has been written to allow addition, deletion, and modification of the beam line elements used in the calculation and to provide a convenient means of repeating such calculations for arbitrary beam lines. Calculations and experimental measurements are compared and found to be in ...

229

The physics of tachyons. Part 4. Tachyon electrodynamics  

Energy Technology Data Exchange (ETDEWEB)

A new formulation of the theory of tachyons using the same two postulates as in special relativity is applied to the electrodynamics of material media. A discussion of Lagrange`s equations and Hamilton`s equations for `classical` charged tachyons shows that such a formalism is a viable approach. An essay is included on why tachyons can be considered to be localised particles for the purpose of calculations. Tachyonic transformations of the electromagnetic fields D, P, H and M are shown to be the same as for bradyonic transformations. Examples discussed include the electric dipole moment of a tachyonic current loop, constitutive equations, polarisation in tachyonic dielectric materials and the velocity of light in tachyonic dielectric media. This is followed by discussions of the collision energy loss for charged tachyons interacting with a material medium and a mathematical proof that tachyons cannot emit Cherenkov radiation when passing ...

1998-12-31

230

The physics of tachyons. Part 4. Tachyon electrodynamics  

International Nuclear Information System (INIS)

A new formulation of the theory of tachyons using the same two postulates as in special relativity is applied to the electrodynamics of material media. A discussion of Lagrange's equations and Hamilton's equations for 'classical' charged tachyons shows that such a formalism is a viable approach. An essay is included on why tachyons can be considered to be localised particles for the purpose of calculations. Tachyonic transformations of the electromagnetic fields D, P, H and M are shown to be the same as for bradyonic transformations. Examples discussed include the electric dipole moment of a tachyonic current loop, constitutive equations, polarisation in tachyonic dielectric materials and the velocity of light in tachyonic dielectric media. This is followed by discussions of the collision energy loss for charged tachyons interacting with a material medium and a mathematical proof that tachyons cannot emit Cherenkov radiation when passing ...

231

Structural, electronic and optical properties of ZnX and CdX compounds (X = Se, Te and S) under hydrostatic pressure  

International Nuclear Information System (INIS)

The structural, electronic and optical properties of ZnX and CdX (X = Se, Te and S) are studied using density functional theory by the Wien2k package. The energy band gap, real and imaginary parts of the dielectric function, energy loss function, optical absorption coefficient and reflectivity spectra of these compounds are calculated. The Engel-Vosko approach improves the energy band gaps of ZnX and CdX compounds. The calculated optical parameters are in good agreement with available experimental results, particularly in the Engel-Vosko approach. Furthermore the effect of hydrostatic pressure on the energy band gap, the real and imaginary parts of the dielectric function of these compounds is studied. The first and second order pressure coefficient for the energy band gaps, the static dielectric function and the static reflectivity spectra are calculated.

2010-09-03

232

Optical properties and electronic structure of ceramics tetragonal PbTiO_3 by using full-potential linearized augmented plane wave  

International Nuclear Information System (INIS)

The electronic structure and optical properties in tetragonal ceramics PbTiO_3, are studied by using full-potential linearized augmented plane wave method in density functional theory with the generalized gradient approximation by WIEN2K package. The theoretical calculated optical properties and energy loss spectrum yield a static refractive index of 2.59 and a plasmon energy of 22.7eV for the tetragonal phase. The effective electron number at low energy saturates near 22-23eV with the value of 50 for the effective electron number. The results show a indirect band gap of 2.2eV at the I' point in the Brillouin zone. The :calculated band structure and density of states of PbTiO_3 agree with previous experimental and theoretical results.

2007-01-01

233

New neutron-rich isotopes in the scandium-to-nickel region, produced by fragmentation of a 500 MeV/u {sup 86}Kr beam  

Energy Technology Data Exchange (ETDEWEB)

We have measured production cross-sections of the new neutron-rich isotopes {sup 58}Ti, {sup 61}V, {sup 63}Cr, {sup 66}Mn, {sup 69}Fe, {sup 71}Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u {sup 86}Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss mesurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parameterization. The resulting prospects for reaching even more neutron-rich isotopes, such as the doubly-magic nuclide {sup 78}Ni, are discussed. (orig.).

1991-10-01

234

New neutron-rich isotopes in the scandium-to-nickel region, produced by fragmentation of a 500 MeV/u sup 86 Kr beam  

Energy Technology Data Exchange (ETDEWEB)

We have measured production cross-sections of the new neutron-rich isotopes {sup 58}Ti, {sup 61}V, {sup 63}Cr, {sup 66}Mn, {sup 69}Fe, {sup 71}Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u {sup 86}Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss measurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parametrization. The resulting prospects for reaching even more neutronrich isotopes, such as the doubly-magic nuclide {sup 78}Ni, are discussed. (orig.).

1992-07-01

235

New neutron-rich isotopes in the scandium-to-nickel region, produced by fragmentation of a 500 MeV/u "8"6Kr beam  

International Nuclear Information System (INIS)

We have measured production cross-sections of the new neutron-rich isotopes "5"8Ti, "6"1V, "6"3Cr, "6"6Mn, "6"9Fe, "7"1Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u "8"6Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss measurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parametrization. The resulting prospects for reaching even more neutronrich isotopes, such as the doubly-magic nuclide "7"8Ni, are discussed. (orig.).

236

Nanostructuring and hardening of LiF crystals irradiated with 3?15 MeV Au ions  

British Library Electronic Table of Contents (United Kingdom)

Modifications of the structure and mechanical properties in LiF crystals irradiated with MeV-energy Au ions have been studied using nanoindentation, atomic force microscopy and optical spectroscopy. The nanostructuring of crystals under a high-fluence irradiation (above 1013 ions/cm2)?was?observed. Nanoindentation tests show a strong ion-induced increase of hardness (up?to 150?200%), which is related to the high volume concentration of complex color centers, defect aggregates, dislocation loops and grain boundaries acting as strong barriers for dislocations. From the?depth profiling of the hardness and energy loss it follows that both nuclear and electronic stopping mechanisms of MeV Au ions contribute to the creation of damage and hardening. Whereas the electronic stopping is dominating i...

2011-01-01

237

Introduction  

International Nuclear Information System (INIS)

In the Introduction the history of the cascade probabilistic method development is described. The calculation model for different charged particles cascade probabilistic functions (CPF) was considered. A new analytical expressions for CPF for electrons, protons, alpha-particles and ions are obtained as well. A new results on mathematical analysis, algorithms, and calculation of CPF with taking into account charged particles energy losses on computer are cited. The peculiarities of these functions are analyzed. The detail analysis of these function behavior in relation from flying particles energy, target atomic number, generation and registration depth, and interactions number is carried out. The program packages in the Windows medium is developed on the visual programming languages: Visual Basic 6.0, Delphi 6.0, C++ Builder 6.0.

238

Gamma-rays and neutrinos from the pulsar wind nebulae  

Energy Technology Data Exchange (ETDEWEB)

We construct the time-dependent radiation model for the pulsar wind nebulae (PWNe), assuming that leptons are accelerated in resonant scattering with heavy nuclei, which are injected into the nebula by the pulsar. The equilibrium spectra of these particles inside the nebula are calculated taking into account their radiation and adiabatic energy losses. The spectra of {gamma}-rays produced by these particles are compared with the observations of the PWNe emitting TeV {gamma}-rays and predictions are made for the expected {gamma}-ray fluxes from other PWNe. Expected neutrino fluxes and neutrino event rates in a 1 km{sup 2} neutrino detector from these nebulae are also calculated. It is concluded that only the Crab Nebula can produce a detectable neutrino event rate in the 1 km{sup 2} neutrino detector. Other PWNe can emit TeV {gamma}-rays on the level of a few percent of that observed from the Crab Nebula.

2005-08-01

239

Extension of energy acceptance of Bragg curve counter at the high-energy end  

Energy Technology Data Exchange (ETDEWEB)

We have developed an energy-extension method of a Bragg curve counter (BCC) at the high-energy end for the measurements of double-differential cross-sections (DDXs) of fragment productions induced by tens of MeV protons. In this method, we estimate the incident energies of the fragments penetrating a BCC on the basis of the energy loss and atomic number (Z). We applied this method to the DDX measurements of the {sup nat}C(p, Li) and {sup nat}C(p, Be) reactions induced by 70 MeV protons. The validity of this method has been confirmed by comparing the DDXs of beryllium with theoretical predictions of the PHITS code and the two-body kinematics. This method improves the energy acceptance of the BCC for light fragments twice as wide as that of a conventional method without remodeling of the BCC and any loss of the original advantages.

2008-07-11

240

Evidence for significant backscattering in near-threshold electron-impact excitation of Ar"7"+(3s#->#3p)  

International Nuclear Information System (INIS)

Measurements of absolute total cross sections for electron-impact excitation of Ar"7"+(3s#->#3p) using a merged-beams electron-energy-loss technique show that near threshold the inelastically scattered electrons are ejected primarily in the backward direction. This unusual angular scattering has not been previously observed for atoms or ions, but may be typical for multiply charged ions. The total cross sections, measured over an energy range to 2.2 eV above threshold, agree with seven-state R-matrix close-coupling calculations. Both close-coupling and distorted-wave calculations also confirm the backscattering observed in these measurements.

241

Defect creation by electronic processes in MgO bombarded with GeV heavy ions  

Energy Technology Data Exchange (ETDEWEB)

To study the defect creation induced by electronic processes in refractory oxides, MgO single crystals were irradiated with high energy tin, uranium and lead ions. Optical absorption measurements showed that F-type centers (oxygen vacancies with trapped electrons) were created during irradiation. The total number of centers per unit area of bombarded sample increases linearly with irradiating fluence. The main part of the point defects was found to arise from electronic processes. The concentration of F-type centers induced by ionization increases with the electronic energy losses. Assuming a saturation of point defect concentration at high fluences, F-type center creation cross sections could be estimated. The influence of irradiation temperature and of the velocity of the bombarding ions are discussed.

1996-12-31

242

Bragg curve spectroscopy of fission fragments by using parallel plate avalanche counters  

Energy Technology Data Exchange (ETDEWEB)

By using a charge-sensitive preamplifier and methods of energy spectroscopy we investigated the response of a parallel plate avalanche counter in order to scan the Bragg curve. The detector was operated in butane, pentane and heptane which also served as stopping gases. In this paper, we report on results obtained with fission fragments from a /sup 252/Cf source. We achieved a separation of the light and heavy fragment groups in the interval of gas absorber thickness from about 500 ..mu..g cm/sup 2/ to 1.5 mg cm/sup 2/. The best energy loss resolution was achieved with pentane at E/papprox.=70 V cm/sup 1/ Torr/sup 1/ resulting in delta..delta..E/..delta..Eapprox.=13%. The corresponding shape of the ..delta..E spectrum reproduces correctly the nuclear charge distribution of the fragments. (orig.).

1985-07-01

243

Aerogels: the leading edge in thermal insulation  

Energy Technology Data Exchange (ETDEWEB)

Banning CFCs in foamed insulations has led to an intensive search for alternatives which do not incur the penalty of increased thickness. The most promising of these are silica aerogels, which have proven to be the leading material, when it comes to thermal insulation and environmental protection. Refrigerators insulated with aerogels have been tested and compared to conventionally insulated ones. Results showed a substantial contribution to the energy performance. Boiler manufacturers using aerogel have been able to reduce energy consumption of water heaters by 20%. Float glass elements evacuated and filled with aerogel as well as aerogel insulated polyester lightwalls and bubble skylights yield excellent U-values and significantly reduced energy losses in buildings. (author)

1995-01-01

244

Absolute cross sections for near-threshold electron-impact excitation of the 3s"2"1S#->#3s3p"1P and 3s"2"1S#->#3s3p"3P transitions in Si"2"+  

International Nuclear Information System (INIS)

Absolute total cross sections for electron-impact excitation of the 3s"2"1S#->#3s3p"3P and 3s"2"1S#->#3s3p"1P transitions in Si"2"+ were measured using the merged electron-ion beams energy-loss technique. The results are compared to R-matrix close-coupling theory, which predicts a strong resonance enhancement of the cross section near the threshold for excitation of the "3P state and this is confirmed by the experiments. The observed disagreement between theory and experiment for the dipole excitation is suggested to be due to resonance interference. copyright 1997 The American Physical Society.

245

Waterjet Techniques for Composite Material Jet Engine ...  

Science.gov (United States)

Page 1. Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Page 15. Page 16. Page ...

1996-06-01

246

Vehicle Technologies Program: Fact #676: May 23, 2011 U.S. Refiners...  

Science.gov (United States)

fuel are produced from a barrel of crude oil by U.S. refiners. Other products such as jet fuel and heating oil make up the remaining one third. Graphic of a barrel of oil...

2011-10-09

247

US Air Force Aircraft in Southeast Asia Tested by the Air Force ...  

Science.gov (United States)

... feet in length, and 26 feet 2 inches high. The AC-119G and AC-119K, are powered with two General Electric J85-17 jet engines pod-mounted ...

1970-03-01

248

The physics of automatic letter sorting  

Science.gov (United States)

The astronomical number of letters handled by the Post Office makes automatic sorting technology essential. Key roles are played by the postcode system and an ink-jet printer that has been developed to use phosphorescent inks.

1988-07-01

249

The Surface Water and Ocean Topography (SWOT) - NASA  

Science.gov (United States)

The ratio of particle velocity to translation speed exceeds 1 for 98% of .... The westward movement of the meandering jet and eddy system transports nutrient- rich ...... J. Hydrometeor., 4, 1044-1066. Gedney, N., P. M. Cox, H. Douville, ...

250

Swift panchromatic observations of the bright gamma-ray burst GRB050525a  

CERN Document Server

The bright gamma-ray burst GRB050525a has been detected with the Swift observatory, providing unique multiwavelength coverage from the very earliest phases of the burst. The X-ray and optical/UV afterglow decay light curves both exhibit a steeper slope ~0.15 days after the burst, indicative of a jet break. The timing of the jet break combined with the total gamma-ray energy of the burst constrains the opening angle of the jet to be 2.5 degrees. We derive an empirical `time-lag' redshift from the BAT data of z_hat = 0.69 +/- 0.02, in good agreement with the spectroscopic redshift of 0.61. Prior to the jet break, the X-ray data can be modelled by a simple power law with index alpha = -1.2. However after 300s the X-ray flux brightens by about 30% compared to the power-law fit. The optical/UV data have a more complex decay, with evidence of a rapidly falling reverse shock component that dominates in the ...

2006-01-01

251

Pressure driven spinning: A multifaceted approach for preparing nanoscaled functionalized fibers, scaffolds, and membranes with advanced materials  

UK PubMed Central (United Kingdom)

Electrospinning, a flexible jet-based fiber, scaffold, and membrane fabrication approach, has been elucidated as having significance to the heath sciences. Its capabilities have been most impressive...Full Text Available

252

Preliminary investigation of performance and starting characteristics of liquid fluorine : liquid oxygen mixtures with jet fuel  

Science.gov (United States)

The performance of jet fuel with an oxidant mixture containing 70 percent liquid fluorine and 30 percent liquid oxygen by weight was investigated in a 500-pound-thrust engine operating at a chamber pressure of 300 pounds per square inch absolute. A one-oxidant-on-one-fuel skewed-hole impinging-jet injector was evaluated in a chamber of characteristic length equal to 50 inches. A maximum experimental specific impulse of 268 pound-seconds per pound was obtained at 25 percent fuel, which corresponds to 96 percent of the maximum theoretical specific impulse based on frozen composition expansion. The maximum characteristic velocity obtained was 6050 feet per second at 23 percent fuel, or 94 percent of the theoretical maximum. The average thrust coefficient was 1.38 for the 500-pound thrust combustion-chamber nozzle used, which was 99 percent of the theoretical (frozen) maximum. Mixtures of fluorine and oxygen were found to be self-igniting with ...

1954-01-01

253

PNNL: News Center - Archives  

Science.gov (United States)

million for advanced energy projects Thu, Sep 29, 2011 - Project Aims to Bring Bio-based Jet Fuel Production to the Northwest Mon, Sep 12, 2011 - Drive like the wind Thu, Aug 25,...

2011-10-09

254

Making Clean Gasoline: The Effect on Jet Fuels.  

Science.gov (United States)

Persistently high concentrations of carbon monoxide and low-altitude ozone in the air of the Nation's major urban centers led Congress in the 1990 Clean Air Act Amendments to mandate changes to the composition of gasoline and diesel fuel. Those gasoline c...

1992-01-01

255

Fragmentation mechanisms of a single molten copper jet penetrating a sodium pool. Transition from thermal to hydrodynamic fragmentation in instantaneous contract interface temperatures below its freezing point  

International Nuclear Information System (INIS)

To clarify the fragmentation mechanism of a molten metallic fuel jet in a sodium pool under high-ejection-velocity conditions that correspond to the medium- and high-burnup conditions in the metallic fuel core of liquid-metal-cooled fast breeder reactors, a series of experiments with molten copper as a metallic fuel simulant and a sodium pool was carried out. Under low-ejection-velocity conditions in the range of an ambient Weber number (Wea) a ? 200, the size of the fragments is confirmed to be almost independent of the initial superheating of the jet. Furthermore, the size of the fragments agrees well with that evaluated using the Rayleigh-Taylor instability model, in which the fragment size is assumed to be equal to half the fastest growing wavelength. This result is qualitatively consistent with the characteristics that the molten jet column with large inertia force owing to the high ejection velocity, which transports ...

2010-03-01

256

FS-1037C Appendix A  

Science.gov (United States)

Telecommunication Union IVDT integrated voice data terminal IXC interexchange carrier JANAP Joint Army-Navy-Air Force Publication(s) JCS Joint Chiefs of Staff JPL Jet Propulsion...

2007-05-31

257

Evaluation of two commercial jet nebulisers and three compressors for the nebulisation of antibiotics.  

UK PubMed Central (United Kingdom)

Nebulised antibiotics have been shown to be beneficial in the treatment of lung infections in cystic fibrosis. Studies on the efficiency of nebuliser systems are constantly required in view of the large...Full Text Available

1994-10-01

258

EPA On-line Tools for Site Assessment Calculation | Ecosystems...  

Science.gov (United States)

MWo = average molecular weight of fuel est. 105 g/mole for gasoline est. 165 g/mole for Jet fuel est. 230 g/mole for diesel fuel MWX = molecular weight of selected chemical...

2011-01-19

259

Department of Natural Resources  

Science.gov (United States)

to end statewide burn ban 09/28/2011 - Commissioner's statement on $80 million biomass to jet fuel award to UW and WSU Media Center | View All News Meetings & Events Saturday Oct...

2011-10-08

260

Circadian Rhythm Sleep Disorders: Part I, Basic Principles, Shift Work and Jet Lag DisordersAn American Academy of Sleep Medicine Review  

UK PubMed Central (United Kingdom)

Objective:This the first of two articles reviewing the scientific literature on the evaluation and treatment of circadian rhythm sleep disorders (CRSDs), employing the methodology...Full Text Available

2007-11-01

261

CFD Approaches for Modelling Bubble Entrainment by an Impinging Jet  

International Nuclear Information System (INIS)

This contribution presents different approaches for the modeling of gas entrainment under water by a plunging jet. Since the generation of bubbles happens on a scale which is smaller than the bubbles, this process cannot be resolved in meso-scale simulations, which include the full length of the jet and its environment. This is why the gas entrainment has to be modeled in meso-scale simulations. In the frame of a Euler-Euler simulation, the local morphology of the phases has to be considered in the drag model. For example, the gas is a continuous phase above the water level but bubbly below the water level. Various drag models are tested and their influence on the gas void fraction below the water level is discussed. The algebraic interface area density (AIAD) model applies a drag coefficient for bubbles and a different drag coefficient for the free surface. If the AIAD model is used for the simulation of impinging jets, ...

5101-01-01

262

BEACON eSpace at Jet Propulsion Laboratory: Estimating the Cost of ...  

Science.gov (United States)

Jan 22, 2011 ... dc.subject.other, Cost cost estimating budgets budget estimating ... dc.title, Estimating the Cost of Doing a Cost Estimate, en_US ...

263

ASME proceedings of the 31. national heat transfer conference: Volume 2. HTD-Volume 324  

Energy Technology Data Exchange (ETDEWEB)

This volume is divided into the following sections: (1) fundamentals of convection heat transfer; (2) fundamentals of heat transfer with impinging jets; and (3) fundamentals of heat transfer augmentation. Separate abstracts were prepared for most papers in this volume.

1996-12-31

264

A study on heat-transfer enhancement by a square-rod array in an impinging jet system  

Energy Technology Data Exchange (ETDEWEB)

An impinging jet is a widely used technique for realizing high heat-transfer rates between a fluid and a surface. However, the area of enhanced heat transfer is limited to the neighborhood of the stagnation point. In this study, heat transfer is augmented remote from the stagnation point in an impinging plane jet system by a rod array located near the wall. Each square rod in the array was positioned normal to the flow direction and parallel to the flat plate surface. The distance between the nozzle and the flat plate (H) and the spacing between the rods and the flat plate surface (C) were changed to find the optimum values. The largest heat-transfer augmentation was obtained for C = 1 mm, H/B = 10, where the jet nozzle width is B. In this case, the heat-transfer coefficient averaged over an area 2B from the stagnation point is about 1.6 times greater compared to that without a rod array.

1996-07-01

265

A study of kerf characteristics in abrasive waterjet machining of graphite/epoxy composite  

Energy Technology Data Exchange (ETDEWEB)

Kerf geometry, kerf wall features, and cutting front characteristics of an Abrasive Waterjet (AWJ) machined Graphite/Epoxy (Gr/Ep) laminate were studied. A macroscopic analyses suggests that geometrical features associated with AWJ machining of Gr/Ep laminates are influenced by three macro regions along the cutting depth. The presence of these regions, including initial damage at jet entry, smooth cutting, and rough cutting near the jet exit, depends on the operating conditions. Design of experiments and analysis of variance were used to determine the effect of cutting parameters on kerf characteristics and to develop empirical models for kerf profile and features of the three distinct macroscopic regions. Cutting front analysis revealed that the mechanisms of material removal in AWJ machining of Gr/Ep do not change over the jet penetration depth. In general, high quality uniform cuts may be obtained by minimizing initial ...

1996-04-01

266

A numerical simulation of the evolution and fate of a FRI jet. The case of 3C 31  

CERN Document Server

The evolution of FRI jets has been long studied in the framework of the FRI-FRII dichotomy. In this paper, we test the present theoretical and observational models via a relativistic numerical simulation of the jets in the radio galaxy 3C 31. We use the parameters derived from the modelling presented by \\cite{lb02a,lb02b} as input parameters for the simulation of the evolution of the source, thus assuming that they have not varied over the lifetime of the source. We simulate about 10 % of the total lifetime of the jets in 3C 31. Realistic density and pressure gradients for the atmosphere are used. The simulation includes an equation of state for a two-component relativistic gas that allows a separate treatment of leptonic and baryonic matter. We compare our results with the modelling of the observational data of the source. Our results show that the bow shock evolves self-similarly at a quasi-constant speed, with slight ...

2007-01-01

267

Surface roughening of superalloys by high pressure pure waterjet  

Energy Technology Data Exchange (ETDEWEB)

A high pressure waterjet has been used to study the surface roughening of superalloys as preparation for thermal spraying. Designed experiments for Mar-M 509 and Rene 80 were carried out for the effects of jet pressure and mass of water delivered per unit area. Comparisons were made of several superalloys in terms of erosion, surface roughness and topology. The mechanism of jet erosion of Rene 80 was studied in relation to its metallurgical microstructure. An MCrAlY coating by shrouded plasma spray was made over a waterjet prepared surface with excellent bonding and having an ideally clean interface.

1995-12-31

268

Service the Two-Piece Flo-Jet Carburetor. Fuel System. Student Manual 3. Small Engine Repair Series. First Edition.  

Science.gov (United States)

This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. The manual explains in pictures and short sentences, written on a low reading level, the job of servicing two-piece flo-jet carburetors. Along with the steps of this repair job, specific safety and caution information is frequently noted. To reinforce consistency in material presented to the slow learners, the pictures and written words correspond exactly with the pictures and wording on a corresponding audiovisual presentation. A progress chart for rating the students is included in the manual. (KC)

1981-12-01

269

Radiant Energy Power Source for Jet Aircraft. Final performance report  

Energy Technology Data Exchange (ETDEWEB)

This report beings with a historical overview on the origin and early beginnings of Radiant Energy Power Source for Jet Aircraft. The report reviews the work done in Phase I (Grant DE-FG01-82CE-15144) and then gives a discussion of Phase II (Grant DE-FG01-86CE-15301). Included is a reasonably detailed discussion of photovoltaic cells and the research and development needed in this area. The report closes with a historical perspective and summary related to situations historically encountered on projects of this nature. 15 refs.

1992-02-01

270

Radiant Energy Power Source for Jet Aircraft  

Energy Technology Data Exchange (ETDEWEB)

This report beings with a historical overview on the origin and early beginnings of Radiant Energy Power Source for Jet Aircraft. The report reviews the work done in Phase I (Grant DE-FG01-82CE-15144) and then gives a discussion of Phase II (Grant DE-FG01-86CE-15301). Included is a reasonably detailed discussion of photovoltaic cells and the research and development needed in this area. The report closes with a historical perspective and summary related to situations historically encountered on projects of this nature. 15 refs.

1992-02-01

271

Post-mortem measurements of fuel retention at JET with MKII-SRP divertor  

International Nuclear Information System (INIS)

The deuterium inventory at JET after 2001-2004 operational campaign has been determined using nuclear reaction analysis (NRA) and secondary ion mass spectrometry (SIMS). A full poloidal set of divertor tiles and a set of outer poloidal limiter (OPL) tiles were analysed providing an estimation for the total deuterium retention of about 66 g. Deuterium is trapped mainly at the inner divertor on horizontal target tile and at the inner divertor louvre area where ?60% of the trapped D is found. The long-term D retention is ?4% of the total D input.

2009-06-15

272

Modification of a gas jet transport system for the supression of heavy-mass fission product homologues  

Energy Technology Data Exchange (ETDEWEB)

The uranium target of a gas jet transport system for fission products has been modified by the addition of an aluminum cover foil. The new modification allows fission fragments of low mass to enter a continuous chemistry system while heavier fragments are stopped in the aluminum. The elimination of the heavier homologues allows development of simpler and faster chemical separation procedures. In addition, since the lighter fragments are slowed down by the cover foil a smaller target chamber can be used. This leads to a reduction in system holdup time.

1987-04-15

273

Modification of a gas jet transport system for the supression of heavy-mass fission product homologues  

International Nuclear Information System (INIS)

The uranium target of a gas jet transport system for fission products has been modified by the addition of an aluminum cover foil. The new modification allows fission fragments of low mass to enter a continuous chemistry system while heavier fragments are stopped in the aluminum. The elimination of the heavier homologues allows development of simpler and faster chemical separation procedures. In addition, since the lighter fragments are slowed down by the cover foil a smaller target chamber can be used. This leads to a reduction in system holdup time. (orig.).

274

Exploring the structure of the proton through polarization observables in l p \\to jet X  

CERN Document Server

We present results for a complete set of polarization observables for jet production in lepton proton collision, where the final state lepton is not observed. The calculations are carried out in collinear factorization at the level of Born diagrams. For all the observables we also provide numerical estimates for typical kinematics of a potential future Electron Ion Collider. On the basis of this numerical study, the prospects for the transverse single target spin asymmetry are particularly promising. This observable is given by a certain quark-gluon correlation function, which has a direct relation to the transverse momentum dependent Sivers parton distribution.

2011-01-01

275

Development of an efficient, low-NOx domestic gas range cooktop. Phase 3. Final report, January 1986-December 1988. Technical report  

Science.gov (United States)

The objective of the program was to develop a domestic cooktop with low-NOx emissions and high efficiency. During the first two phases of the program, three design concepts were developed, and two versions of developmental prototypes using the IR-Jet approach were fabricated and tested. The third phase was initiated to address the design issues of a simmer setting, air/gas metering, and jet plate durability and to develop prototypes for interested manufacturers.

1989-10-01

276

Combining laser chemical processing and aerosol jet printing: a laboratory scale feasibility study  

British Library Electronic Table of Contents (United Kingdom)

Abstract First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high-efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti-reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two-step fine-line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright 2010 John Wiley & Sons, Ltd.

2011-01-01

277

Beam lifetime and emittance growth in RHIC under normal operating conditions with the hydrogen gas jet, the cluster-jet and pellet targets  

International Nuclear Information System (INIS)

The inelastic scattering of the beam and the residual gas molecules in RHIC could represent one of the limitations on the beam life time and emittance growth. This report covers the dominant central nuclear collisions influence on the beam lifetime and transverse emittance growth. The cross sections for the beam-gas electron radiative captures are an order of magnitude smaller. The capture cross sections include the radiative and non-radiative capture, and the capture from the electron-positron pair creation from the 'vacuum capture'.

2010-09-01

278

Washboard modes as ELM-related events in JET  

Energy Technology Data Exchange (ETDEWEB)

Washboard (WB) modes (Smeulders P et al 1999 Plasma Phys. Control. Fusion 41 1303) are a very common edge instability regularly observed in the H-mode regime in JET. They are detected as (normally several) bands of continuously fluctuating magnetic activity rotating in the direction of the electron diamagnetic drift with typical frequencies in the range of 10-90 kHz. The time evolution of the WB mode frequency is found to follow qualitatively the evolution of the electron temperature measured near the pedestal top, probably due to the strong diamagnetic drift associated with the large pedestal gradients. Evidence for their involvement in the pedestal and ELM dynamics will be presented. Increasing WB mode amplitude is correlated with an increase in the time between consecutive type-I ELMs. In situations in which a sudden increase (decrease) of WB mode activity is observed, the build-up of the pedestal temperature (and, linked to this, also of the pedestal pressure) ...

2004-01-01

279

Laser Raman scattering measurements of differential molecular diffusion in turbulent nonpremixed jet flames of H{sub 2}/CO{sub 2} fuel  

Science.gov (United States)

This paper explores effects of differential diffusion in nonpremixed turbulent jet flames. Pulsed Raman scattering spectroscopy is used to measure temperature and species concentrations in chemically reacting jets of H{sub 2}/CO{sub 2} into air, over a range of jet Reynolds numbers from 1,000 to 30,000 based on cold jet fluid properties. Results show significant effects of differential diffusion at all jet Reynolds numbers considered. Differential diffusion between H{sub 2} and C0{sub 2} produces differences between the hydrogen element mixture fraction ({xi}{sub H}) and the carbon element mixture fraction ({xi}{sub c}). The greatest effects occur on the rich side of stoichiometric, where {xi}{sub H} is observed to be smaller than {xi}{sub C} at all Reynolds numbers. Differential diffusion between H{sub 2} and H{sub 2}O creates a net flux of hydrogen element toward the ...

1994-01-01

280

Heat transfer augmentation of axisymmetric impinging jet using a perforated plate set in front of a target plate. 1st report effects of diameter and pitch of holes in a perforated plate  

Energy Technology Data Exchange (ETDEWEB)

Concerning heat transfer augmentation of an axisymmetric impinging jet using a perforated plate set, the bore of the hole in the plate for local and averge heat transfer rate, pitch, and effect of the distance between perforated plate and target plate were examined. Heat transfer augmentation was examined under the condition of 0.063 /ge/d/D /ge/0.200, 1.25 /ge/p/d /ge/4.00, Re is approximately equal to 18000, (where d is the bore of the hole in the plate, D is the axisymmetric nozzle outlet bore, p is the pitch of the perforated plate, and Re is the jet Reynolds number). The findings are as follows; The velocity of the small jet after passing the perforated plate is reduced, and resistance to disturbance is remarkably large. The small jet which is not at the center hole extends to the outside of the plate. The heat transfer rate at a stagnation point is high when the target plate is placed in the ...

1988-07-25

281

Dynamic behaviour of dc double anode plasma torch at atmospheric pressure  

International Nuclear Information System (INIS)

An original dc double anode plasma torch which provides a long-time and highly stable atmospheric plasma jet has been devised for the purpose of hazardous waste treatment. The arc fluctuations and dynamic behaviour of the argon and argon-nitrogen plasma jets under different operating conditions have been investigated by means of classical tools, such as the statistic method, fast Fourier transform (FFT) and correlation analysis. In our experiments, the takeover mode is identified as the fluctuation characteristic of the argon plasma jet while the restrike mode is typical in the argon-nitrogen plasma dynamic behaviour. In the case of pure argon, the FFT and correlation calculation results of electrical signals exhibit the only characteristic frequency of 150 Hz, which originates from the torch power and is independent of any change in the operating conditions. It indicates that the nature of fluctuations in an argon plasma ...

2007-07-07

282

Strong ionizing events distributed along medium energy #alpha# particle tracks recorded in nuclear emulsion  

International Nuclear Information System (INIS)

Track analysis of medium energy #alpha# particle trajectories recorded in fine grain nuclear emulsion submitted to specific intensifying treatments led to the observation of strong ionizing events (SIE) sticking out of the primary's track core. Preliminary determinations showed that the number of SIEs increases with the primary's energy, and that their production is of more than one order of magnitude higher than the number of Rutherford recoils. The presence of SIEs on monoenergetic #alpha# tracks also has a significant influence on the measured range distribution, which, expressed in terms of energy loss, results in a mean contribution to the total energy loss of far reaching (SIEs (radial spread >= 0.458 #mu#m) of proportional 25 keV per 13.6 MeV #alpha# particle, instead of 0.75 keV in the case where only the Rutherford interactions are taken into account. Measurements carried out in detectors ...

283

Pulse height response of Si surface barrier detectors to 5-70 MeV heavy ions  

Energy Technology Data Exchange (ETDEWEB)

An extensive series of pulse height measurements have been performed in partially depleted Si surface barrier detectors, using various heavy ions (Li, B, C, O, Al and Cl), at energies between 5 and 70 MeV. After correcting for the small energy loss of the incident ions in traversing the gold surface barrier layer of the detector and for the residual nuclear stopping, the resulting pulse heights per MeV for the various heavy ions were found to be up to 2.5% larger than for the {sup 241}Am (5.486 MeV) alpha particle. This increase, although significant, is smaller than had been anticipated from an extrapolation of the earlier study of H, He and Li pulse heights by Lennard et al.. A new method of analysis of pulse height data, which significantly reduces the uncertainties associated with the dead layer energy loss and nuclear stopping corrections, was used in order to determine directly the variation of ...

1992-04-01

284

European Cogeneration Certificate Trading ECoCerT. Demand creation and scheme interactions  

International Nuclear Information System (INIS)

Once the definition of the CHP (combined heat and power generation) certificate is clear, demand for it can be organised in several ways. A well-designed system of mandatory demand, by means of an obligation to acquire a certain amount of CHP certificates each year, is effective to meet the policy target. The voluntary willingness to pay for CHP certificates is likely to be small, resulting in a very thin market. Finally, instead of creating a demand solely targeted at the CHP certificates, demand could also result from interacting policy schemes such as emissions trading. Assuming that a CHP certificate scheme is going to be introduced, we would recommend to issue standard CHP certificates based on additional ('fuel-free') kWh output (substitution approach with standard certificates) and create demand by means of an incentive on electricity supply companies to purchase CHP certificates. The incentive could either be quantitative (an ...

2003-01-01

285

Two Avowable Quantum Communication Schemes  

International Nuclear Information System (INIS)

Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.

2008-11-15

286

Two Avowable Quantum Communication Schemes  

Science.gov (United States)

Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein Podolsky Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.

2008-11-01

287

System protection considerations related to single pole tripping of high-voltage transmission lines  

Science.gov (United States)

Single and selective pole tripping schemes may be used to maintain a desired level of system integrity while minimizing transmission line expenditures. In general, these schemes will be most effective on those portions of the system where relatively few interconnections exist. While selective pole tripping may superficially appear to provide more margin than single pole schemes in the preservation of system stability, it seems unlikely that in those actual applications where single pole tripping is warranted that selective pole tripping will provide any significant advantages.

1975-01-01

288

Pumped-storage hydropower schemes  

Energy Technology Data Exchange (ETDEWEB)

The general types of pumped-storage plants and considerations for determining their need, use, and selection are presented. A brief discussion of TVA's experience on two pumped-storage schemes is included. Pumped-storage plants have become an integral part of many hydropower systems. Most of these systems use pumped-storage plants to meet power requirements during the peak load demands. In any application, large or small, the expected load demand and supply source must be identified to select the best scheme required for the particular system.

1984-01-01

289

Consistent Higher-Order Corrections to Stop_i -> Sbottom_j H^+ in the Complex MSSM  

CERN Document Server

We review an analysis of a consistent renormalization of the top and bottom quark/squark sector of the MSSM with complex parameters (cMSSM). Various renormalization schemes are defined, analyzed analytically and tested numerically in the decays Stop_2 -> Sbottom_i H^+/W^+ (i = 1,2). No scheme is found that produces numerically acceptable results over all the cMSSM parameter space, where problems occur mostly already for real parameters. Some numerical examples for Gamma(Stop_2 -> Sbottom_1 H^+) in our preferred scheme, "m_b, A_b DRbar" are shown.

2010-01-01

290

gamma. /sub 5/ in dimensional regularization  

Energy Technology Data Exchange (ETDEWEB)

By generalizing the algebra satisfied by the ..gamma../sub 5/ matrix, it is possible to give an extension of ..gamma../sub 5/ to d dimensions. We discuss the connection of this scheme to others.

1985-02-07

291

el5 in dimensional regularization  

Energy Technology Data Exchange (ETDEWEB)

By generalizing the algebra satisfied by the el5 matrix, it is possible to give an extension of el5 to d dimensions. We discuss the connection of this scheme to others. (orig.).

1985-02-07

292

Using Multiple Coding Schemes to Understand Argument in In the Jury Room  

British Library Electronic Table of Contents (United Kingdom)

The present study analyzes argument in jury deliberations by using the Conversational Argument Coding Scheme (CACS) and the content of juror argument using Subject Matter Argument Assessment (SMAA) (Pettus, 1990). The main purpose is to illustrate how the two coding schemes can complement each other to provide rich yet systematic characterization of argument in jury deliberation. Jury deliberations drawn from In the Jury Room, a televised news series on jury deliberation, are coded and analyzed using CACS and SMAA. The researchers found that using two argument coding schemes is beneficial in learning about the types of arguments jurors make and the subject matter about which they argue. The study results are compared with findings from previous studies of juror argument behavior, suggestin...

2010-01-01

293

Secure Direct Communication Based on Non-Orthogonal Entangled Pairs and Local Measurement  

Science.gov (United States)

We propose a quantum secure direct communication scheme based on non-orthogonal entangled pairs and local measurement. In this scheme, we use eight non-orthogonal entangled pairs to act as quantum channels. Due to the non-orthogonality of the quantum channels, the present protocol can availably prohibit from all kinds of valid eavesdropping and acquire a secure quantum channel. By local measurement, the sender acquires a secret random sequence. The process of encoding on the random sequence is identical to the one in one-time-pad. So the present protocol is secure. Even for a highly lossy channel, our scheme is also valid. The scheme is feasible with present-day techniques.

2008-12-01

294

Scalable quantum computing with atomic ensembles  

International Nuclear Information System (INIS)

Atomic ensembles, comprising clouds of atoms addressed by laser fields, provide an attractive system for both the storage of quantum information and the coherent conversion of quantum information between atomic and optical degrees of freedom. We describe a scheme for full-scale quantum computing with atomic ensembles, in which qubits are encoded in symmetric collective excitations of many atoms. We consider the most important sources of error-imperfect exciton-photon coupling and photon losses-and demonstrate that the scheme is extremely robust against these processes: the required photon emission and collection efficiency threshold is #approx#>86%. Our scheme uses similar methods to those already demonstrated experimentally in the context of quantum repeater schemes and yet has information processing capabilities far beyond those proposals.

2010-09-01

295

Performance-Aware Power Management in Embedded Controllers with Multiple-Voltage Processors  

CERN Document Server

The goal of this work is to minimize the energy dissipation of embedded controllers without jeopardizing the quality of control (QoC). Taking advantage of the dynamic voltage scaling (DVS) technology, this paper develops a performance-aware power management scheme for embedded controllers with processors that allow multiple voltage levels. The periods of control tasks are adapted online with respect to the current QoC, thus facilitating additional energy reduction over standard DVS. To avoid the waste of CPU resources as a result of the discrete voltage levels, a resource reclaiming mechanism is employed to maximize the CPU utilization and also to improve the QoC. Simulations are conducted to evaluate the performance of the proposed scheme. Compared with the optimal standard DVS scheme, the proposed scheme is shown to be able to save remarkably more energy while maintaining comparable QoC.

2008-01-01

296

Nuclear data sheets for A = 101  

Energy Technology Data Exchange (ETDEWEB)

Detailed level and decay schemes are presented for the nuclei of the A = 101 mass chain. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comments are given in the text.

1985-08-01

297

Nuclear data sheets for A = 101  

International Nuclear Information System (INIS)

Detailed level and decay schemes are presented for the nuclei of the A = 101 mass chain. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comments are given in the text.

298

New and old Sn isomers produced in heavy-ion collisions  

International Nuclear Information System (INIS)

The energy level schemes of tin isotopes produced in the heavy ion reactions are presented. The using of #gamma# spectroscopy technique is also described. 4 refs, 12 figs.

1991-12-01

299

Energy level schemes and binding energies for nuclei in the region of 140  

International Nuclear Information System (INIS)

Russian 1987. p. 99-100. USSR Sabalyauskas, L.Yu. Vanagas, VV Guseva,

1987-04-14

300

Electron capture decay of "2"0"3Bi  

International Nuclear Information System (INIS)

The electron capture decay scheme of "2"0"3Bi is studied. Energies and relative intensities of gamma rays are given.

301

Development of linear sensitivity matrix method for fast evaluation of CANDU refuelling schemes  

International Nuclear Information System (INIS)

In order to develop a numerical tool for the fast evaluation of CANDU refuelling schemes, a Linear Sensitivity Matrix method (LSM) is developed. It assumes that all the effects caused by various perturbations to the core state are independent to each other and the core response to a perturbation is proportional to its magnitude. In this way, the main core parameters of a refuelling scheme can be derived by simple algebraic operations with the use of pre-calculated sensitivity matrices, without resorting to the complicated and time-consuming 3D core calculation. Verification against the Qinshan CANDU reactor operation history demonstrates that LSM is capable of generating accurate results and running very fast for evaluating a refuelling scheme. (authors)

2009-06-01

302

Development of an Adaptive Tsetse Population Management Scheme for the Luke Community, Ethiopia  

Science.gov (United States)

... African agro-pastoral system: Management of tsetse and bovine trypanosomiasis. Ecological Economics 65:1, 125-135Online publication date: ... ...

303

Charging systems and PAYT experiences for waste management in Spain  

British Library Electronic Table of Contents (United Kingdom)

Municipal waste charges in Spain are very widespread, although their application varies significantly among different municipalities. Most commonly, waste charges are implemented as a flat rate, but some of them depend on indicators such as household water consumption, the land area of the property or the value of the real estate. Only one residential pay-as-you-throw scheme has been applied so far. It was a pay-per-bag scheme implemented in Torrelles de Llobregat, Barcelona. A number of other systems focussing only on commercial waste have been implemented in Spain. Several factors suggest that new pay-as-you-throw schemes will be adopted in the near future. In 2000 no municipalities had door-to-door collection schemes; since then over 70 municipalities have implemented them. In addition ...

2008-01-01

304

Bandwidth Allocation to Interactive Users in DBS-Based ...  

Science.gov (United States)

... end-to-end TCP connection from the hybrid terminal ... peculiar to self-similar stochastic processes, ... Queue First (MDQF) schemes are employed at the ...

2011-05-13

305

Relative correlation of Jet-REMPI monitoring with adsorption tube sampling followed by TDS-CIS-GC/MS  

Energy Technology Data Exchange (ETDEWEB)

During earlier work rapid and highly sensitive Jet-REMPI (resonance-enhanced multiphoton ionization) mass spectrometry was applied for monitoring the effluent from thermal treatment of a filter dust during a de novo test under laboratory conditions. The sample, from ESP-Field 2 of an iron ore sintering plant, was already loaded with dioxins ({sigma}PCDD/F = 132 ng/g), their precursors (PCBz, PCPh) and other products of incomplete combustion. Heating filter dust in a temperature window 200-350 C under a flow of air results in further formation of these pollutants. As described elsewhere, on-line detection was mostly carried out using a non-selective ionization mode, to measure a wide range of compounds simultaneously. The changes of output suggest that the reaction products increase in chlorination level with time. Another explanation is that higherchlorinated compounds appear later as a consequence of lower volatility and stronger adsorption. However, due to mass ...

2004-09-15

306

Realistic Probability Estimates For Destructive Overpressure Events In Heated Center Wing Tanks Of Commercial Jet Aircraft  

Energy Technology Data Exchange (ETDEWEB)

The Federal Aviation Administration (FAA) identified 17 accidents that may have resulted from fuel tank explosions on commercial aircraft from 1959 to 2001. Seven events involved JP 4 or JP 4/Jet A mixtures that are no longer used for commercial aircraft fuel. The remaining 10 events involved Jet A or Jet A1 fuels that are in current use by the commercial aircraft industry. Four fuel tank explosions occurred in center wing tanks (CWTs) where on-board appliances can potentially transfer heat to the tank. These tanks are designated as ''Heated Center Wing Tanks'' (HCWT). Since 1996, the FAA has significantly increased the rate at which it has mandated airworthiness directives (ADs) directed at elimination of ignition sources. This effort includes the adoption, in 2001, of Special Federal Aviation Regulation 88 of 14 CFR part 21 (SFAR 88 ''Fuel Tank System Fault Tolerance ...

2007-02-07

307

Development and use of localized arc filament plasma actuators for high-speed flow control  

International Nuclear Information System (INIS)

The paper discusses recent results on the development of localized arc filament plasma actuators and their use in controlling high-speed and high Reynolds number jet flows. Multiple plasma actuators (up to 8) are controlled using a custom-built 8-channel high-voltage pulsed plasma generator. The plasma generator independently controls pulse repetition rate (0-200 kHz), duty cycle and phase for each individual actuator. Current and voltage measurements demonstrated the power consumption of each actuator to be quite low (20 W at 20% duty cycle). Emission spectroscopy temperature measurements in the pulsed arc filament showed rapid temperature increase over the first 10-20 ?s of arc operation, from below 1000 deg. C to up to about 2000 deg. C. At longer discharge pulse durations, 20-100 ?s, the plasma temperature levels off at approximately 2000 deg. C. Modelling calculations using an unsteady, quasi-one-dimensional arc filament model showed that rapid localized ...

2007-02-07

308

Aspects of two-photon physics at linear e"+e"- colliders  

International Nuclear Information System (INIS)

We discuss various reactions at future e"+e"- and #gamma##gamma# colliders involving real (beamstrahlung or backscattered laser) or quasi-real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large transverse momentum p_T is described in some detail; we give distributions for the rapidity and p_T of the jets as well as the di-jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties that arise from the at present rather poor knowledge of the parton content of the photon. We also present results for 'mono-jet' production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production of W and Z bosons. Where appropriate, the two-photon processes are compared with annihilation reactions leading to similar ...

309

Synchrotron Self-Compton Analysis of TeV X-ray Selected BL Lacertae Objects  

CERN Document Server

We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux from XBLs is nonthermal synchrotron radiation emitted by isotropically-distributed electrons in the randomly oriented magnetic field of a relativistic blazar jet, we obtain the electron spectrum. This spectrum is then used to deduce the synchrotron self-Compton (SSC) spectrum as a function of the Doppler factor, magnetic field, and variability timescale. The variability timescale is used to infer the comoving blob radius from light travel-time arguments, leaving only two parameters. With this approach, we accurately simulate the synchrotron and SSC spectrum of flaring XBLs in the Thomson through Klein-Nishina regimes. Photoabsorption by interactions with internal jet radiation and the intergalactic background light (IBL) is included. Doppler factors, magnetic fields, ...

2008-01-01

310

Results of reliability test program on light water reactor piping  

Energy Technology Data Exchange (ETDEWEB)

The Japan Atomic Energy Research Institute has conducted a piping reliability test program to demonstrate the safety and reliability of light water reactor primary piping. In this program, pipe fatigue test, leak-before-break (LBB) verification test and pipe rupture test were carried out to examine the integrity of piping, to verify the LBB and to demonstrate the effectiveness of protective measures against jet impingement and pipe whip loads under a pipe rupture event.In the pipe fatigue test, a procedure to predict the fatigue crack growth was developed, and the integrity of piping during the plant service life was evaluated. In the LBB verification test, the pipe fracture test and the leak rate test were performed to verify the LBB in the primary piping.In the pipe rupture test, the influence of jet impingement on the target disk and the deformation behavior of whipping pipe and restraint were investigated. Using the test results, the ...

1994-12-01

311

Quirks at the Tevatron and Beyond  

CERN Document Server

We consider the physics and collider phenomenology of quirks that transform nontrivially under QCD color, SU(2)_W as well as an SU(N)_{ic} infracolor group. Our main motivation is to show that the recent Wjj excess observed by CDF naturally arises in quirky models. The basic pattern is that several different quirky states can be produced, some of which beta-decay during or after spin-down, leaving the lightest electrically neutral quirks to hadronize into a meson that subsequently decays into gluon jets. We analyze LEP II, Tevatron, UA2, and electroweak precision constraints, identifying the simplest viable models: scalar quirks ("squirks") transforming as color triplets, SU(2)_W triplets and singlets, all with vanishing hypercharge. We calculate production cross sections, weak decay, spin-down, meson decay rates, and estimate efficiencies. The novel features of our quirky model includes: quirkonium decay proceeds into a pair of gluon jets, ...

2011-01-01

312

Overview of reliability test program on primary coolant piping of light water reactors  

Energy Technology Data Exchange (ETDEWEB)

Upon request by the Science and Technology Agency of Japanese Government, the Japan Atomic Energy Research Institute has conducted Piping Reliability Test Program to demonstrate the safety and reliability of light water reactor primary pipings. In this report, the results of the program are summarized. In the test program, pipe fatigue tests, Leak-Before-Break (LBB) verification tests and pipe rupture tests were carried out to examine the integrity of pipings, to verify the LBB concept and to demonstrate the effectiveness of the protective measures against jet impingement and pipe whip under pipe rupture event, respectively. In the pipe fatigue tests, a procedure to predict the fatigue crack growth was developed and the integrity of piping during plant service life was demonstrated. In the LBB verification tests, pipe fracture tests and leak rate tests were performed using cracked pipes. Based on the test results, LBB in the primary pipings was demonstrated. In the ...

1993-10-01

313

Multipass laser mass spectrometer with extreme jet-cooled pulsed gas  

International Nuclear Information System (INIS)

We have developed a photon accumulated laser mass spectrometer that enables us to identify isomers of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran. This system is comprised of a high temperature (230 deg. C) pulsed gas injector (PGI), multimirror multipath system (MMS), and the conventional time-of-flight mass spectrometer. The PGI induces the formation of a choked supersonic jet gas pulse that cools down to a temperature to restrain fragmentation and reduces vibrational and rotational thermal noises. The results suggest that the excited lifetime numbers and fragment dynamics of these species change completely with jet cooling of molecules. The MMS enhances the soft ionization efficiency (by a factor of 1000 over a single path system) through photon accumulation by extending the irradiation duration (to about 40 ns) and volume, and it further minimizes fragmentation by carefully controlling the laser intensity distribution ...

2006-09-01

314

Development of an efficient, low-NOx domestic gas-range cooktop. Phase 3. Annual technical report, January 1986-December 1986  

Science.gov (United States)

The objective of the program is to develop a domestic cooktop with low-NOx emissions and high efficiency. During the first two phases of the program, three design concepts were developed, and two versions of developmental prototypes using the IR-Jet approach were fabricated and tested. The third phase was initiated to address the design issues of burner turndown and modulation and to conduct the field test of a prototype with one IR-Jet and three conventional burners. Two prototypes containing one IR-Jet and three conventional burners and utilizing blower speed control for air/gas modulation were fabricated. One unit employed a brushless dc motor and the other a 2-pole ac motor. The ac motor prototype was field tested. Field testing showed the need for a mechanical air/gas valve for modulation and for a 1500 Btu/hr simmer setting. A 4-inch-diameter stepped-tile configuration provided input rates from 1500 to 8000 Btu/hr. A ...

1987-06-01

315

Abrasion wear studies with abrasives from brown coal beneficiation  

Energy Technology Data Exchange (ETDEWEB)

This paper evaluates abrasive jet wear tests, carried out on the ZUK-3M abrasion apparatus according to the GOSF 23.201-78 industrial standard. As abrasive material, brown coal coke dust, brown coal dust, power plant fly ash and quartz sand (for the purpose of comparison) were employed. Seventeen types of materials were blasted with abrasive jets, including a selection of steels, glass, rubber, SYS-pur plastics, cast basalt, Kawenit and vitroceramics. The test apparatus produced abrasive jet velocities between 12 and 130 ms/SUP/-/SUP/1 at rotor revolutions of 1,000 to 10,000 min/SUP/-/SUP/1. Blasted material samples were arranged at angles between 15 and 90 degrees. Various tables and graphs present abrasivity results. These results were employed for technical modifications of dedusting equipment in briquetting and coking plants, which led to a threefold increase in service life of abrasion endangered equipment parts. (8 ...

1983-01-01

316

AGN Feedback: Does it work?  

CERN Document Server

While feedback is important in theoretical models, we do not really know if it works in reality. Feedback from jets appears to be sufficient to keep the cooling flows in clusters from cooling too much and it may be sufficient to regulate black hole growth in dominant cluster galaxies. Only about 10% of all quasars, however, have powerful radio jets, so jet-related feedback cannot be generic. The outflows could potentially be a more common form of AGN feedback, but measuring mass and energy outflow rates is a challenging task, the main unknown being the location and geometry of the absorbing medium. Using a novel technique, we made first such measurement in NGC 4051 using XMM data and found the mass and energy outflow rates to be 4 to 5 orders of magnitude below those required for efficient feedback. To test whether the outflow velocity in NGC 4051 is unusually low, we compared the ratio of outflow velocity to escape ...

2009-01-01

317

A gas-jet ECR ion source at TRIGA-SPEC  

International Nuclear Information System (INIS)

The TRIGA-SPEC experiment has been installed recently at the research reactor TRIGA Mainz. Ground state properties like masses, charge radii, spins, and moments of short-lived nuclides can be determined with very-high precision using the Penning trap mass spectrometer TRIGA-TRAP, and the collinear laser spectroscopy setup TRIGA-LASER. Short-lived neutron-rich radionuclides in the mass range 80 < A < 140 are produced by thermal neutron induced fission of e.g. U-235, Pu-239 or Cf-249, respectively. For the extraction and ionization of the fission products a gas-jet system is coupled to a 2.45-GHz ECR ion source for the production of singly charged ions. The gas-jet has been tested on-line and fission products have been extracted. First off-line tests of the ion source have been performed successfully with argon gas. The results of the commissioning test of the ion source and the on-line coupling of the experiments are presented.

2010-03-08

318

A Distinctive Disk-Jet Coupling in the Seyfert-1 AGN NGC 4051  

CERN Document Server

We report on the results of a simultaneous monitoring campaign employing eight Chandra X-ray (0.5-10 keV) and six VLA/EVLA (8.4 GHz) radio observations of NGC 4051 over seven months. Evidence for compact jets is observed in the 8.4 GHz radio band; This builds on mounting evidence that jet production may be prevalent even in radio-quiet Seyferts. Assuming comparatively negligible local diffuse emission in the nucleus, the results also demonstrate an inverse correlation of L_radio proportional to L_X-ray ^(-0.72+/-0.04) . Current research linking the mass of supermassive black holes and stellar-mass black holes in the "low/hard" state to X-ray luminosities and radio luminosities suggest a "fundamental plane of accretion onto black holes" that has a positive correlation of L_radio proportional to L_X-ray^(0.67+/-0.12) . Our simultaneous results differ from this relation by more than 11 sigma, indicating that a separate mode of accretion and ...

2010-01-01

319

Measurement of the charge asymmetry in top-antitop quark production with the CDF II experiment  

Energy Technology Data Exchange (ETDEWEB)

The Fermi National Laboratory (Fermilab) operates the Tevatron proton-antiproton collider at a center-of-mass energy of {radical}s = 1.96 TeV, the is therefore the only collider which is today able to produce the heaviest known particle, the top quark. The top quark was discovered at the Tevatron by the CDF and D0 collaborations in 1995. At the Tevatron, most top quarks are produced via the strong interaction, whereby quark-antiquark annihilation dominates with 85%, and gluon fusion contributes with 15%. Considering next-to-leading order (NLO) contributions in the cross section of top-antitop quark production, leads to a slight positive asymmetry in the differential distribution of the production angle {alpha} of the top quarks. This asymmetry is due to the interference of certain NLO contributions. The charge asymmetry A in the cosine of {alpha} is predicted [14] to amount to 4-6%. Information about the partonic rest frame, necessary for a measurement of A in the observable cos ...

2006-12-01

320

Transverse velocity modulator and generator schemes based on non-collinear radiation and electron beams  

International Nuclear Information System (INIS)

New non-collinear schemes are suggested for transverse velocity modulation of electron beams and for the generation of coherent spontaneous radiation by these transversely modulated beams. It is shown that due to the non-collinearity some orders of magnitude enhancement can be achieved for the coherent spontaneous radiation (CSR) power at both the fundamental and harmonic frequencies.

2000-05-01

321

Theoretical studies of Cerro Prieto brines chemical equilibria  

Energy Technology Data Exchange (ETDEWEB)

A chemical equilibrium model is used, implemented in a compact FORTRAN package called HITEQ, to investigate possible mineral deposition related to prereinjection treatment of Cerro Prieto brines for silica removal. Large saturation ratios of the treated brines with respect to several minerals are indicated by these computations. As a remedy, an inexpensive CO/sub 2/ removal scheme aimed at inhibiting carbonate mineral precipitation is proposed. This scheme is quantitatively discussed with the aid of HITEQ. It is concluded that the proposed treatment is both technically and economically feasible.

1980-02-01

322

Secure direct communication using the 'polarization' entangled atomic ensembles  

Energy Technology Data Exchange (ETDEWEB)

We propose a scheme with potential experimental realization to generate 'polarization' entanglement between two atomic ensembles and show one of the applications - a novel secure communication allowing asymptotically key distribution and quasisecure direct communication. The scheme involves laser manipulation of atomic ensembles, adjustable quarter- and half-wave plates, beam splitters, polarizing beam splitters and single-photon detectors, and well fits the status of the current experimental technology.

2004-02-14

323

Scalar fields in the dimensional reduction scheme for symmetric spaces  

Energy Technology Data Exchange (ETDEWEB)

The authors study the general features of the dimensional reduction scheme for multi-dimensional spaces of the type M/sup 4/ x S/R, S/R being a symmetric coset space. The properties of the scalar potentials of the reduced theories are investigated and an effective method of explicit calculation of these potentials is elaborated. They consider also a wide class of embeddings of Lie subalgebras into simple Lie algebras resulting in reduced theories of physical interest.

1989-01-01

324

On a canonical class of Green currents for the unit sections of abelian schemes  

CERN Document Server

We show that on any abelian scheme over a complex quasi-projective smooth variety, there is a Green current for the zero-section, which is axiomatically determined up to $\\partial$ and $\\bar\\partial$-exact differential forms. This current generalizes the Siegel functions defined on elliptic curves. We prove generalizations of classical properties of Siegel functions, like distribution relations, limit formulae and reciprocity laws.

2011-01-01

325

Nuclear Data Sheets for A -- 216, 220, 224, and 228  

International Nuclear Information System (INIS)

Detailed level schemes, decay schemes, and the experimental data on which they are based are presented for all nuclei with mass numbers A -- 216, 220, 224, and 228. The experimental data are evaluated; inconsistencies and discrepancies are noted; and adopted values for level and #gamma#-ray energies, #gamma# intensities, as well as for other nuclear properties are given.

326

Neural classifier construction using regularization, pruning and test error estimation.  

Science.gov (United States)

In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems. PMID:12662736

1998-12-01

327

Measuring-Basis Encrypted Quantum Key Distribution with Four-State Systems  

International Nuclear Information System (INIS)

A measuring-basis encrypted quantum key distribution scheme is proposed by using twelve nonorthogonal states in a four-state system and the measuring-basis encryption technique. In this scheme, two bits of classical information can be encoded on one four-state particle and the transmitted particles can be fully used.

2007-01-15

328

Information technology security at the Advanced Photon Source  

International Nuclear Information System (INIS)

The proliferation of 'botnets,' phishing schemes, denial-of-service attacks, root kits, and other cyber attack schemes designed to capture a system or network creates a climate of concern for system administrators, especially for those managing accelerator and large experimental-physics facilities, as they are very public targets. This paper will describe the steps being taken at the Advanced Photon Source (APS) to protect the infrastructure of the overall network with emphasis on security for the APS control system.

2007-10-15

329

Decay scheme data for [sup 101]Mo and [sup 101]Tc  

Energy Technology Data Exchange (ETDEWEB)

New measurements of relative gamma-ray emission probabilities in the decay of [sup 101]Mo and [sup 101]Tc are reported. Previously published conversion-electron data have been used along with the gamma-ray data to formulate self-consistent decay schemes. (orig.)

1993-10-01

330

Decay scheme data for "1"0"1Mo and "1"0"1Tc  

International Nuclear Information System (INIS)

New measurements of relative gamma-ray emission probabilities in the decay of "1"0"1Mo and "1"0"1Tc are reported. Previously published conversion-electron data have been used along with the gamma-ray data to formulate self-consistent decay schemes. (orig.).

331

Competition between strong and decoupling schemes in "1"8"7Ir  

International Nuclear Information System (INIS)

Low spin states (Jscheme is extended to include also strong coupling. Excellent agreement including that for the low spin states is found in "1"8"7Ir to which this theory is applied. (Auth.).

332

Wavelength shift of lasing from a dye-doped asymmetrically deformed liquid jet  

International Nuclear Information System (INIS)

We examined the spectral behaviors of lasing from a asymmetrically deformed liquid jet (a ? 14 ?m) which is induced by a laterally flowing gas. Th liquid sample was methanols which contains DCM dye. When n distortion is induced, the lasing spectrum appears as two periodic peaks which are corresponding to the resonance modes of cylindrical cavity. As the distortion parameter exceeds about 4%, the lasing spectrum shifts continuously to short wavelength. When the distortion parameter reaches ? 10%, the amount of blue shift was ? 30 nm. The blue shift can be explained as the shift of optimum wavelength of threshold curves. From the absorption and fluorescence curve of liquid sample, we estimated the spoiled Q with the distortion parameter.

1997-11-01

333

The utility of naphthyl-keratin adducts as biomarkers for jet-fuel exposure.  

Science.gov (United States)

We investigated the association between biomarkers of dermal exposure, naphthyl-keratin adducts (NKA), and urine naphthalene biomarker levels in 105 workers routinely exposed to jet-fuel. A moderate correlation was observed between NKA and urine naphthalene levels (p?=?0.061). The NKA, post-exposure breath naphthalene, and male gender were associated with an increase, while CYP2E1*6 DD and GSTT1-plus (++/+-) genotypes were associated with a decrease in urine naphthalene level (p?

2011-09-30

334

The spatial distribution of argon clusters in gas jet  

International Nuclear Information System (INIS)

The spatial distribution of argon clusters in gas jet is tested using the Rayleigh scattering method. A pulsed laser is used to acquire the whole evolution of the cluster inside one event. The measured results at a fixed axial position show that the argon clusters grow in less than one millisecond after the nozzle is opened and the cluster size keeps constant during the whole open period of 20 ms. Further results show that the scattering signal along the radial direction is almost Gaussian-distributed and the full width half maximum (FWHM) increases almost linearly when the distance from nozzle increases. The scattering signal along the axial direction is Landau-distributed and the area near the nozzle is most effective for laser cluster interaction. (authors)

2010-02-01

335

The electron cyclotron absorption diagnostic for the JET pumped divertor plasma  

International Nuclear Information System (INIS)

We present the design of a diagnostic system to measure electron cyclotron absorption at the second harmonic E-mode resonance in the JET pumped divertor plasma. The diagnostic will measure transmission as a function of frequency along one or more sightlines from which the spatial profile of the n_eT_e product will be deduced. The divertor is briefly described, and the electron cyclotron resonance physics relevant to this measurement is reviewed. The problems of measuring transmission using an oversized transmission system are discussed and the chosen measurement technique, a swept frequency interferometer using a coherent radiation source, is described. A prototype of the instrument has been assembled to test the measurement technique. Some data demonstrating the instrument's characteristics are presented. The nonresonant losses, which may affect the interpretation of the measurement, are also discussed. (orig.).

1993-03-01

336

The Dynamical Interaction of AGN with their Galaxian Environments  

CERN Document Server

Jet-driven shocks are responsible for an important fraction of the emission of the narrow-line regions (NLRs) in many classes of AGN. However, this cannot explain all observations. It is clear that the remaining sources are photoionised by the active nucleus. The 2-d hydrodynamic models from the RSAA group support an evolutionary scenario whereby the shock-excited NLRs are initially jet-driven but later, ionizing photons from the central engine replace shocks as the main excitation mechanism and shock induced star formation may also become important. In their photoionized phase, dusty and radiation-pressure dominated evolution produces a self-regulated NLR spectrum. This model aso explains the coronal emission lines and fast (3000 km s$^{-1}$) outflows seen in some Seyferts.

2003-01-01

337

Overview of long-term fuel inventory and co-deposition in castellated beryllium limiters at JET  

International Nuclear Information System (INIS)

Morphology of castellated Be tiles from the belt limiter exposed to the JET plasma for 56,000 s was examined on both sides of castellated grooves, on plasma-facing and side surfaces of the tiles. The essential results are (i) deuterium retention in the castellated grooves and in other locations is associated with co-deposition of carbon; (ii) the decay length of deposition in the castellation is around 1.5 mm; (iii) no deuterium is detected in bulk Be; (iv) bridging of gaps by molten beryllium occurred but gaps were not filled with Be; (v) on side surfaces of the tiles the formation of BeO layer was detected at a distance of 20 mm and more from the plasma-facing surface. The consequences for a long-term operation of a reactor-class device with several different plasma-facing materials are addressed.

2009-04-30

338

Macro-Cellular Silicon carbide Reactors for Nonstationary Combustion Under Piston Engine-Like Conditions  

British Library Electronic Table of Contents (United Kingdom)

Strut lattice structures of reaction-bonded silicon infiltrated silicon carbide ceramics (RB-SiSiC) for air-fuel mixture formation and for nonstationary lean-burn under pressure applications were fabricated. The lattice design with a high porosity >80% was shaped by indirect three-dimensional printing. It was shown that pre-ignition processes in the porous reactor are much faster than in a free combustion, especially at lower temperatures. Interaction of high velocity diesel jets with cylindrical strut ligaments of the SiSiC lattice structure offers a new possibility for quick and efficient fuel distribution (multi-jet splitting) in space.

2011-01-01

339

Ion temperature anisotropy in high power helium neutral beam fuelling experiments in JET  

Energy Technology Data Exchange (ETDEWEB)

During helium beam fuelling experiments in JET, distinctive anisotropic features have been observed in the velocity distribution function describing both fast and thermal alpha particle populations. During the initial fuelling phase the central helium ion temperature observed perpendicular to the magnetic field is higher than the central electron temperature, while the central helium ion temperature observed parallel to the magnetic field is lower than or equal to the central electron temperature. In order to verify temperature measurements of both perpendicular and parallel lines of sight, other independent methods of deducing the ion temperature are investigated: deuterium ion temperature, deuterium density, comparison with neutron rates and profiles (influence of a possible metastable population of helium). 6 refs., 7 figs.

1994-07-01

340

Investigation of erosion-corrosion of 3003 aluminum alloy in ethylene glycol-water solution by impingement jet system  

British Library Electronic Table of Contents (United Kingdom)

Erosion-corrosion (E-C) of 3003 aluminum (Al) alloy in ethylene glycol-water solutions were studied by weight-loss and electrochemical measurements as well as surface characterization through an impingement jet system. Al alloy E-C is dominated by erosion components, i.e., pure erosion and corrosion-enhanced erosion, which account for 92-97% of the total E-C rate under the various conditions in this work. Contribution from corrosion components, including pure corrosion and erosion-enhanced corrosion, is slight. With the increase of fluid flow velocity and sand concentration, the total E-C rate increases. Compared with the significant increase of the rates of erosion components, the increase of the rate of corrosion component is negligible. Upon fluid flow, passivity of Al alloy that develo...

2009-01-01

341

Heat transfer augmentation in an axisymmetric impinging jet  

Science.gov (United States)

This paper presents the experimental results of heat transfer augmentation in an axisymmetric jet impinging normally on a flat plate surface without the requirement of additional pumping power. The present technique of augmentation utilizes only a punched plate with circular holes arranged in a triangular array, fixed parallel to, just in front of the heated target plate. Near the optimum conditions determined, the heat transfer coefficient at the geometrical stagnation point can be increased 4 times. Additional flow visualization study indicates that this augmentation mechanism creates an improved flow field where the punched plate acts as a detached fin, the conductivity of which may be exploited for further augmentation. Besides augmentation, the present investigation foresees the possibility of manipulating the distribution of local heat transfer rate by varying few parameters.

1982-01-01

342

Functional adaptation of microbial communities from jet fuel-contaminated soil under bioremediation treatment: simulation of pollutant rebound  

British Library Electronic Table of Contents (United Kingdom)

Abstract To investigate the link between the functionality and the diversity of microbial communities under strong selective pressure from pollutants, two types of mesocosms that simulate natural attenuation and phytoremediation were generated using soil from a site highly contaminated with jet fuel and under air-sparging treatment. An increase in the petroleum hydrocarbon concentration from 4900 to 18-500-mg-kg-1-dw soil simulated a pollutant rebound (postremediation pollutant reversal due to residual contamination). Analysis of soil bacterial communities by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed stronger changes and selection for a phylogenetically diverse microbial population in the mesocosms with pollutant-tolerant willow trees. Enumerat...

2011-01-01

343

Experimental investigations of plasma bullets  

International Nuclear Information System (INIS)

Recently several investigators reported on various means of generating cold plasma jets at atmospheric pressure. More interestingly, these jets turned out to be not continuous plasmas but trains of small high velocity plasma packets/bullets. However, until now little is known of the nature of these 'bullets'. Here we present experimental insights into the physical and chemical characteristics of bullets. We show that their time of initiation, their velocity and the distance they travel are directly dependent on the value of the applied voltage. We also show that these bullets can be controlled by the application of an external electric field. Using an intensified charge coupled device camera we report on their geometrical shape, which was revealed to be 'donut' shaped, therefore giving an indication that solitary surface ionization waves may be responsible for the creation of these bullets. In addition, using emission spectroscopy, we follow ...

2009-03-07

344

Excitation of global Alfven Eigenmodes by RF heating in JET  

Energy Technology Data Exchange (ETDEWEB)

The alpha-particle confinement of future D-T experiments at JET can be severely degraded by Global Alfven Eigenmodes (AE). Scenarios for the excitation of Alfven Eigenmodes in usual (e.g. D-D) plasmas are proposed, which provide a MHD diagnostic and allow the study of the transport of super-Alfvenic ions. Active studies with separate control of TAE amplitude and energetic particle destabilization, measuring the plasma response, give more information than passive studies, in particular concerning the damping mechanisms. The TAE excitation can be achieved by means of the saddle coil and the ICRH antenna. The experimental method is introduced together with a theoretical model for RF excitation. (authors). 6 refs., 3 figs.

1994-07-01

345

Efficient, low emissions gas range cooktop  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a gas-fired cooktop for a range which provides high thermal efficiency and low emissions of air pollutants, particularly low levels of NO{sub x}. The cooktop includes a perforated tile burner which radiates infrared energy upward at a high flux rate to rapidly quench burner gas temperatures and inhibit the formation of NO{sub x}. A perforated glass-ceramic jet plate positioned between the burner and a cooking vessel transmits most of the radiant infrared energy from the burner to the vessel and also forms jets of combustion products which are directed against the bottom of the vessel fo convective heating. Thermal efficiencies of up to about 70% and NO{sub x} emissions as low as about 15ppM are achieved by the cooktop.

1990-01-09

346

Dependence of nitriding degree of Ti surface by non-LTE nitrogen plasma on various plasma parameters  

International Nuclear Information System (INIS)

Experiments of plasma nitriding of titanium are carried out by two plasma sources. One is a microwave discharge plasma source under several Torr, and the other is a nitrogen arc jet generated under atmospheric pressure followed by rapid expansion into a gas wind tunnel. The relationship between the surface density of nitrogen atoms in the #alpha#-Ti and various plasma parameters is systematically studied. For the microwave nitrogen plasma, it is found that the effect of the vibration temperature is the most essential for the surface nitriding, whereas the effect of electron temperature, density and rotation temperature is less remarkable. It is also found that the higher vibration temperature of the microwave discharge nitrogen plasma makes the target temperature higher, and consequently, the surface density of atomic nitrogen remarkably increased. However, the effect of target temperature is less remarkable for the arc jet nitrogen plasma.

2004-06-01

347

Definitive generic study for the effect of high lift airfoils on wind turbine effectiveness, executive summary  

Science.gov (United States)

The effect of high lift airfoils on the cost effectiveness of HAWT and VAWT (horizontal and vertical axis wind turbine) machines is studied. The scope involved first studying modern two dimensional airfoils, and developing a generalized formulation for their performance in terms of lift, drag, and thickness at appropriate Reynolds numbers. Single element, multi-element, symmetrical, extra thick airfoils and jet flap airfoils were analyzed. The jet flap airfoils were considered to be unacceptable because of excessive power requirements. Then the effect of using the above airfoils on the rotors of a variety of wind turbines was made. Qualitative representation of the type of airfoils studied is given.

1979-05-01

348

Computer simulations of reacting particle-laden jet mixing applied to SO_2 control by dry sorbent injection  

International Nuclear Information System (INIS)

A particle-laden turbulent reacting flow model is described and applied to in-furnace, dry SO_2 control in boilers. Sulfur capture by calcium-based sorbents is represented by a shrinking core model which accounts for surface areas loss and product layer diffusion. Sorbent particle trajectories and dispersion are followed with cloud statistics in a Lagrangian framework. The turbulent fluid mechanics and chemical reactions are coupled, and solutions obtained for mean and fluctuating velocity, composition, and particle position. Comparisons are made with data from an US EPA laboratory reactor. Practical implications for SO_2 control are examined including the effects of jet velocity, sorbent injection location, boiler load and thermal profiles.

1992-11-01

349

Chemistry of dense clumps near moving Herbig-Haro objects  

British Library Electronic Table of Contents (United Kingdom)

Abstract Localized regions of enhanced emission from HCO+, NH3 and other species near Herbig-Haro objects (HHOs) have been interpreted as arising in a photochemistry stimulated by the HHO radiation on high-density quiescent clumps in molecular clouds. Static models of this process have been successful in accounting for the variety of molecular species arising ahead of the jet; however, recent observations show that the enhanced molecular emission is widespread along the jet as well as ahead. Hence, a realistic model must take into account the movement of the radiation field past the clump. It was previously unclear as to whether the short interaction time between the clump and the HHO in a moving source model would allow molecules such as HCO+ to reach high enough levels, and to survive fo...

2011-01-01

350

Blowdown thrust force under pipe rupture accident. Pt. 1. Experimental evaluations of blowdown thrust force and decompression characteristics  

Energy Technology Data Exchange (ETDEWEB)

Blowdown thrust forces and decompression characteristics were evaluated concerning the jet discharge or pipe whip tests with a 4-inch or 6-inch diameter pipe under PWR LOCA or BWR LOCA conditions related to pipe rupture accidents in nuclear power plants. This paper presents experimental evaluations of time-dependent and maximum blowdown thrust forces, and evaluations of decompression characteristics under instantaneous pipe rupture conditions. The following items are discussed: the peak value of the blowdown thrust force, the jet thrust coefficient for the maximum blowdown thrust force, the pressure recovery after break, and the relationship between the pressure undershoot of the sudden decompression and the decompression rate.

1984-06-01

351

Beryllium coating on JET Inconel tiles  

International Nuclear Information System (INIS)

Full text: Institute for Nuclear Research, Pitesti-Mioveni, Romania in direct cooperation with the National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest studied and prepared for coating more than 1000 tiles made of Inconel with 7-9 #mu#m of beryllium for nuclear fusion applications at JET, Culham, UK. The principles of manufacturing processes using thermal evaporation and plasma ignited in pure metal vapors as well as by Thermionic Vacuum Arc (TVA) method and the properties of the Ni and Be coatings are presented. The prepared beryllium layers were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and atomic force microscopy. (authors)

2009-10-12

352

Analytical studies of four-inch pipe whip tests under BWR LOCA conditions  

Energy Technology Data Exchange (ETDEWEB)

The purpose of pipe rupture studies in JAERI is to perform model tests on pipe whip, restraint behavior, jet impingement and jet thrust force, and to establish a computational method for analyzing these phenomena. This report presents the analytical results of 4-inch pipe whip tests under BWR LOCA conditions. Dynamic response analyses were performed using the general-purpose finite element program ADINA. The test pipe was modelled by straight beam elements and the four restraints were modelled by a single truss element. The analytical results were compared with the experimental results. Impact time and maximum total restraint force showed good agreement with experimental results. On the other hand, pipe strain and pipe deflection could not be predicted so well. The reason for this is that the sliding of the restraint during the pipe whip movement cannot be considered in the analyses.

1985-01-01

353

Analysis of catalyst deactivation during steam reforming of jet fuel on Ni-(PdRh)/g-Al2O3 catalyst  

British Library Electronic Table of Contents (United Kingdom)

Catalyst deactivation during steam reforming of transportation fuels, primarily due to sulfur poisoning and carbon deposition, is a major hurdle in the commercialization of fuel cell technologies. In an attempt to better understand the phenomena, a previously formulated multi-component (Ni, Pd, Rh) catalyst supported on g-Al2O3 was studied under steam reforming of Jet A spiked with thiophene to achieve a total sulfur content of 1000ppm by weight. Analysis of fresh catalysts showed the presence of two groups of active metal particles, primarily distinguished by their size and composition; small particles (1-5nm) largely comprised of Rh and large particles (10-20nm) that were predominantly Ni, with or without the presence of Pd. Analysis of used catalysts showed sintering of crystallites con...

2011-01-01

354

Studies on energy level schemes of some nuclei by Gamma-ray spectroscopy  

International Nuclear Information System (INIS)

several authors tried to drive codes to construct nuclear level scheme of nuclei using a set of measured gamma -ray transitions and known energy levels, Ritz combination principle proved to be useful in constructing a more complete decay scheme. In this thesis the energy level schemes of some nuclei have been investigated by the measurements of the gamma - ray energies and use of Ritz combination code. The nuclei under investigation are "110m Ag (253 d)"110 Cd and "166m Ho (1200 yr) "166 E r. On the basis of the suggested level at 2249.02 keV by the Ritz code new positions of the two gamma-ray transitions at 677.5 and 706.6 KeV are found in decay scheme of "110m Ag. Also by this code, new position for the 994.84 KeV gamma-ray transition were established to depopulate the level at 1075.2 KeV.

1984-01-01

355

High Order Finite Volume Nonlinear Schemes for the Boltzmann Transport Equation  

Energy Technology Data Exchange (ETDEWEB)

The authors apply the nonlinear WENO (Weighted Essentially Nonoscillatory) scheme to the spatial discretization of the Boltzmann Transport Equation modeling linear particle transport. The method is a finite volume scheme which ensures not only conservation, but also provides for a more natural handling of boundary conditions, material properties and source terms, as well as an easier parallel implementation and post processing. It is nonlinear in the sense that the stencil depends on the solution at each time step or iteration level. By biasing the gradient calculation towards the stencil with smaller derivatives, the scheme eliminates the Gibb's phenomenon with oscillations of size O(1) and reduces them to O(h{sup r}), where h is the mesh size and r is the order of accuracy. The current implementation is three-dimensional, generalized for unequally spaced meshes, fully parallelized, and up to fifth order accurate ...

2005-03-29

356

Compressed Neighbor Discovery for Wireless Networks  

CERN Document Server

This paper studies neighbor discovery problem in wireless networks. A novel scheme, called compressed neighbor discovery is proposed, which assigns each node a unique signature and let nodes simultaneously transmit their signatures during the discovery period. The query node then determines, based on the superposition of the signatures, a small number of nodes as its neighbors, out of a large number of nodes in the network. This is fundamentally a sparse recovery problem. Using the proposed scheme, a single frame time suffices to achieve reliable discovery for large networks. This is in contrast to conventional schemes, where each node repeatedly transmits its identity with random delay, so that a receiver can identify each neighbor at least once without collision. Two practical, low-complexity discovery schemes are studied. The first scheme assigns sparse pseudo-random on-off ...

2010-01-01

357

Automated Categorization Scheme for Digital Libraries in Distance Learning: A Pattern Recognition Approach  

Science.gov (United States)

Digital libraries play a crucial role in distance learning. Nowadays, they are one of the fundamental information sources for the students enrolled in this learning system. These libraries contain huge amount of instructional data (text, audio and video) offered by the distance learning program. Organization of the digital libraries is therefore very important for easy and fast access to the desired information. Improper categorization of data may mislead the students searching the library. Since manual categorization of huge amount of data might be challenging, an automatic and reliable method is needed. In this sense, this paper proposes an automated categorization scheme for digital libraries in distance learning. The categorization scheme is designed and developed by a pattern recognition approach. Effectiveness of the proposed scheme is evaluated on widely used Reuters database. The results of the ...

2008-10-01

358

An Optimized Lifetime Enhancement Scheme for Data Gathering in Wireless Sensor Networks  

CERN Document Server

Design of energy efficient schemes for data gathering is an important concern for lifetime enhancement of wireless sensor networks. Variation in the distances of nodes from the Base Station and differences in inter-nodal distances are primary factors causing unequal energy dissipation among the nodes. Thus energy difference between the various nodes increases with time resulting in degraded network performance. The LEACH and PEGASIS schemes which provided elegant solutions to the problem suffer basic drawbacks due to randomization of cluster heads and greedy chain formation respectively. In this paper, we propose an Optimized Lifetime Enhancement (OLE) Scheme which shows enhanced performance over these schemes. OLE increases the network performance by ensuring a sub-optimal energy dissipation of the individual nodes despite their random deployment. It employs modern heuristics like particle swarm ...

2010-01-01

359

A proposed scheme for coal fired combined cycle and its concise performance  

Energy Technology Data Exchange (ETDEWEB)

For IGCC, the primary investment is too high due to the demand of high gasification efficiency. For PFBCC, the thermal efficiency is too low due to the relatively low turbine inlet temperature and the hot working medium of the gas turbine is not easy to clean. A new scheme is proposed for coal fired combined cycle to overcome the main drawbacks of IGCC and PFBCC. The research targets are developing a new cycle construction of coal fired combined cycle to raise the efficiency and reduce the primary investment. Actually, the new scheme is a synthesis of some existing proposals. It adopts partial gasification to reduce the primary investment of the gasification equipment. The un-gasified surplus solid is then fed to a pressurized fluidized bed boiler, but adopting Curtiss Wright type external combustion to lower the ash content in the working medium. The gas fuel from the partial gasifier is combusted in a top combustor to further increase the ...

2007-06-15

360

The interaction of fast alpha particles with pellet ablation clouds  

International Nuclear Information System (INIS)

The energy spectra of energetic confined alpha particles are being measured using the pellet charge exchange method [R. K. Fisher, J. S. Leffler, A. M. Howald, and P. B. Parks, Fusion Technol. 13, 536 (1988)]. The technique uses the dense ablation cloud surrounding an injected impurity pellet to neutralize a fraction of the incident alpha particles, allowing them to escape from the plasma where their energy spectrum can be measured using a neutral particle analyzer. The signal calculations given in the above-mentioned reference disregarded the effects of the alpha particles' helical Larmor orbits, which causes the alphas to make multiple passes through the cloud. Other effects such as electron ionization by plasma and ablation cloud electrons and the effect of the charge state composition of the cloud, were also neglected. This report considers these issues, reformulates the signal level calculation, and uses a Monte-Carlo approach to calculate the neutralization fractions. The ...

361

Superplastic deformation of nitrogen-rich Ca-#alpha#-sialon ceramics  

International Nuclear Information System (INIS)

Nitrogen-rich Ca-#alpha#-sialon ceramics, prepared with CaH_2 as one of the starting powders, were compressively deformed in spark plasma sintering equipment. Compared with the oxygen-rich Ca-#alpha#-sialons, increasing onset deformation temperatures (about 150 K higher) were observed for nitrogen-rich Ca-#alpha#-sialons deformed at a rate of 2 x 10"-"3 s"-"1. High hardness (H_V_1_0 = 18-20 GPa) and toughness (K_I_C = 4-7 MPa m"1"/"2) were maintained after the deformation. Anisotropic grain growth was found to take place during deformation, resulting in anisotropic microstructures, containing coarse and elongated grains. The observed differences in deformation behaviour and properties between nitrogen-rich and oxygen-rich Ca-#alpha#-sialons are, as indicated by transmission electron microscopy and electron energy loss spectroscopy analysis, attributed to the presence of reduced amounts of a nitrogen-rich grain-boundary glass phase.

2008-02-25

362

Stress-assisted crystallisation in anodic titania  

International Nuclear Information System (INIS)

Research highlights: ? Correlations between microstructure and internal stress during Ti anodising are established. ? Large internal compressive stresses are accumulated in the film during anodising upto 12 V. ?A transition from compressive to tensile stress is observed when the cell voltage exceeds 12 V. ? At 40 V, the oxide films consist of two regions with different compositions and microstructures. Crystallisation of amorphous to anatase TiO2 contributes to the compressive stress relaxation. - Abstract: The relationship between the microstructural and internal stress evolution during Ti anodising is discussed. Samples anodised galvanostatically to 12 V and 40 V, corresponding to different stages of the internal stress evolution, were examined by in-plane and cross-section transmission electron microscopy. Electron diffraction patterns have been complemented with stoichiometry data obtained from energy loss near edge structure spectra. The ...

2011-04-01

363

Spectral dependence of ultrasonic attenuation for hydrided Zr-2.5%Nb Alloy  

International Nuclear Information System (INIS)

The cold-worked Zr-2.5%Nb alloy is used as material for the pressure tubes in CANDU nuclear reactors. During the service life in reactor, diffusion of hydrogen and/or deuterium in the pressure tubes wall occur. Below a certain temperature, a stable hydride of zirconium is formed, as a brittle phase which can lead to catastrophic failures. For this reason, it is very important to be able to investigate the hydrogen effect on the micro structural properties of zirconium alloys. In the present paper a non-destructive testing technique is used, known as ultrasonic spectral analysis. When an ultrasonic signal traverses a medium, the frequency components associated with the input signal are altered. By frequency analysing the reflected signals, it is possible to study and compare the material properties. The two major parameters measured in ultrasonic spectroscopy are the attenuation and the velocity of the waves. Attenuation is determined by the energy ...

2009-10-12

364

Pairing effects in nucleon transfer reactions in the system sup 144 Sm+ sup 88 Sr at 4. 7 MeV/u  

Energy Technology Data Exchange (ETDEWEB)

Proton and neutron transfer populating low-lying states have been studied in the system {sup 144}Sm+{sup 88}Sr at an energy below the Coulomb barrier. The experimental cross sections for the single proton transfer are well reproduced by DWBA-calculations using spectroscopic information from light ion reactions. The two-proton transfer appears enhanced relative to the uncorrelated sequential transfer of single protons. The same holds for the transfer of proton pairs, the enhancement is kept for the second pair. This is interpreted as a supercurrent between two superfluid nuclear proton-pair wave functions: More mass and charge is transported per time unit in pairs than by single nucleons. Neutron transfer is observed with large cross sections and is found to contribute to the energy loss observed in the transfer reactions. For mixed proton-neutron transfers the sequential nature of the transfer reactions is established in a similar way as for ...

1990-05-01

365

Pairing effects in nucleon transfer reactions in the system "1"4"4Sm+"8"8Sr at 4.7 MeV/u  

International Nuclear Information System (INIS)

Proton and neutron transfer populating low-lying states have been studied in the system "1"4"4Sm+"8"8Sr at an energy below the Coulomb barrier. The experimental cross sections for the single proton transfer are well reproduced by DWBA-calculations using spectroscopic information from light ion reactions. The two-proton transfer appears enhanced relative to the uncorrelated sequential transfer of single protons. The same holds for the transfer of proton pairs, the enhancement is kept for the second pair. This is interpreted as a supercurrent between two superfluid nuclear proton-pair wave functions: More mass and charge is transported per time unit in pairs than by single nucleons. Neutron transfer is observed with large cross sections and is found to contribute to the energy loss observed in the transfer reactions. For mixed proton-neutron transfers the sequential nature of the transfer reactions is established in a similar way as for the ...

366

Outlook for using wind energy for electrification of agriculture in Estonian SSR  

Energy Technology Data Exchange (ETDEWEB)

The developed electrical networks in the agricultural regions of the Estonian SSR make it possible to construct relatively powerful wind power plants at the sites of the most favorable wind conditions with small outlays for the power transmission lines. The wind power plant electricity can be used to electrify the production processes in agriculture, while the surplus can be supplied to the energy system. The inclusion of the wind power plants in the energy system makes it possible to improve the total generation of energy or reduce the consumption of fuel. With the efficient arrangement of the wind power plants, one can also reduce the energy losses during its transfer. Calculations indicated that in the coastal zones of the Estonian SSR, one can obtain specific power of 420-480 kW/km/sup 2/. For comparison it is indicated that the Estonian SSR in the agricultural regions now uses 8-12 kW/km/sup 2/. The wind-energy potential of the coastal ...

1982-01-01

367

M X-ray production in Nd, Gd, Ho and Lu by 1-6 MeV lithium ions  

Energy Technology Data Exchange (ETDEWEB)

M-shell X-rays of the rare-earth elements {sub 60}Nd, {sub 64}Gd, {sub 67}Ho and {sub 71}Lu were measured for lithium ion bombardment in the energy range 1.0-6.0 MeV. The M-shell X-rays with energies of 0.978-1.631 keV were detected with a LINK analytical detector. The efficiency of the detector was determined by using the known atomic-field bremsstrahlung cross-sections from low energy electron beams and K-shell X-ray measurements with light projectiles. The measured cross-sections are compared to the predictions of the first Born approximation and the ECPSSR (energy loss and Coulomb deflection effects, perturbed stationary state approximation with relativistic correction) theories. The best theoretical description of the present data is given by the ECPSSR theory, even though the discrepancy between data and theory is increasing at higher projectile energies.

2004-06-01

368

High-efficiency solar cell and method for fabrication  

Science.gov (United States)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical ...

1999-08-31

369

High lithium ion conductive Li7La3Zr2O12 by inclusion of both Al and Si  

British Library Electronic Table of Contents (United Kingdom)

High lithium-ion (Li^+) conductive garnet-structured lanthanum lithium zirconate (LLZ) solid electrolyte is prepared by incorporation of appropriate amounts of silicon (Si) and aluminum (Al). The resultant pelletized LLZ obtains total Li^+ conductivity of 6.8x10^-^4Scm^-^1 at 298K. This improved conductivity is nearly identical with the bulk Li^+ conductivity of the LLZ reported earlier, suggesting that the grain boundary resistance is effectively reduced by the incorporation of Si and Al. Microanalyses by transmission electron microscopy coupled with energy-dispersive X-ray microanalysis and electron energy-loss spectroscopy revealed the presence of amorphous Li-Al-Si-O with nano crystalline LiAlSiO4 at grain boundaries. Fast lithium-ion transport around the amorphous Li-Al-Si-O/LiAlSiO4 ...

2011-01-01

370

Epitaxial stabilization of MnO(111) overlayers on a Pd(100) surface  

International Nuclear Information System (INIS)

The growth of epitaxial MnO(100) and MnO(111) layers on Pd(100) surface has been investigated by spot-profile analysis low-energy electron diffraction, dynamic atomic force microscopy, photoemission and high-resolution electron energy loss spectroscopy, and density functional theory. We have found that despite the large lattice mismatch to the Pd(100) substrate, the MnO(100) layers are kinetically stabilized at low temperatures (?350 deg. C) and at oxygen pressures between 2x10-7 and 5x10-7 mbar. Annealing in ultrahigh vacuum at 650 deg. C or, alternatively, deposition of manganese metal in oxygen pressure -7 mbar causes the transformation of the MnO(100) to a polar MnO(111) surface, which is decorated by triangular pyramids with (100) side facets. It is suggested that the growth of MnO(111) layers is energetically preferred over MnO(100) due to the epitaxial stabilization at the metal-oxide interface.

2007-06-01

371

Diffuse $\\gamma$-rays and $\\bar{p}$ flux from dark matter annihilation -- a model for consistent results with EGRET and cosmic ray data  

CERN Document Server

In this work we develop a new propagation model for the Galactic cosmic rays based on the GALPROP code, including contributions from dark matter annihilation. The model predicts compatible Galactic diffuse $\\gamma$ ray spectra with EGRET data in all sky regions. It also gives consistent results of the diffuse $\\gamma$ ray longitude and latitude distributions. Further the results for B/C, $^{10}$Be/$^9$Be, proton, electron and antiproton spectra are also consistent with cosmic ray measurements. In the model we have taken a universal proton spectrum throughout the Galaxy without introducing large fluctuation for the proton energy loss is negligible. The dark matter annihilation signals are `boosted' after taking the contribution from subhalos into account. Another interesting feature of the model is that it gives better description of the diffuse $\\gamma$ rays when taking the source distribution compatible with supernova remnants data, which ...

2007-01-01

372

Determination of the initial energy in computerized tomography with proton beams; Determinacao da energia inicial em tomografia computadorizada com feixe de protons  

Energy Technology Data Exchange (ETDEWEB)

In earliest works devoted to proton computed tomography it was shown that the advantage of pCT image reconstruction appears when the energy is close to the Bragg peak region, since the proton passes the object. This effect provided by the Bragg peak makes the computerized tomography with protons possible. However, when decreasing the initial proton energy, with the increase of the irradiation dose, there are two effects that work simultaneously in opposite ways. First, the energy loss of a proton in an object becomes bigger at small initial energy. At the same time decreasing of the proton energy results in the increase of the energy straggling, requiring a larger number of protons. In this work the radiation dose dependence on the proton initial energy was studied using analytical formulas and computer simulations. The investigation determined that the radiation dose practically does not depend on the initial energy, except in the energy ...

2007-07-01

373

Absolute cross sections for near-threshold electron-impact excitation of the 2s"2S#->#2p"2P transition in C"3"+  

International Nuclear Information System (INIS)

Absolute total cross sections for electron-impact excitation of the 2s"2S#->#2p"2P transition in C"3"+ were measured from 7.35 eV to 8.45 eV using the merged electron-ion-beams energy-loss technique. The results settle the discrepancy between two previous experiments using the crossed-beams fluorescence method, being in very good agreement with the older results [P. O. Taylor, D. Gregory, G. H. Dunn, R. A. Phaneuf, and D. H. Crandall, Phys. Rev. Lett. 39, 1256 (1977)] but less so with the more recent ones [D. W. Savin, L. D. Gardner, D. B. Reisenfeld, A. R. Young, and J. L. Kohl, Phys. Rev. A 51, 2162 (1995)]. The present measurements are also in good agreement with unitarized Coulomb-Born and close-coupling calculations. copyright 1998 The American Physical Society.

374

A partitioned central solar receiver  

International Nuclear Information System (INIS)

Else of solar energy as substitute for conventional fuels at a competitive cost requires efficient conversion from solar radiation to usable forms of energy. In solar thermal or thermochemical applications, high efficiency usually re- quires high temperature and high concentration of incoming radiation. The main form of energy loss from high temperature solar central receivers is thermal emission ('re radiation'), at an effective temperature close to the maximum receiver temperature. This loss is reduced if the aperture is divided into segments, most of which are maintained at lower temperatures. A two-stage partitioned receiver demonstrating this concept is under construction at the Weizman Solar Tower. The high-temperature stage is the DIAPR (Directly Irradiated Annular Pressurized Receiver). The low-temperature stage is made of tubular cavity receivers of simpler design. Preliminary optical and thermal design of the partitioned receiver is ...

1996-05-01

375

A Bragg curve counter with an active cathode to improve the energy threshold in fragment measurements  

Energy Technology Data Exchange (ETDEWEB)

We have developed a Bragg curve counter (BCC) equipped with an active cathode to extend the energy acceptance to lower energies than for a conventional BCC to measure differential cross-sections of fragment production reactions induced by tens of MeV protons. The signal from the active cathode providing the timing signal of fragment incidence and the time difference signal between the cathode and anode gives information on the fragment range in the BCC on the basis of electron drift time. Utilization of the range information made possible identification of fragments less than 0.5 MeV/u that is lower than the identification threshold of a conventional BCC technique. After investigations on fundamental properties of a newly constructed BCC using heavy ion beams and alpha-particles, this method was applied successfully to a fragment production measurement for 70 MeV proton-induced reactions on carbon. With this technique, the energy threshold of the BCC was improved without introducing an ...

2008-05-01

376

Testing and modification of a simple flow turbine; Messtechnische Untersuchung und Modifikation einer einfachen Durchstroemturbine  

Energy Technology Data Exchange (ETDEWEB)

A study conducted at the IHS had the aim to obtain basic information on whether it is possible to build flow turbines following the free jet principle that are on a par with, or superior to, the conventional design, especially in terms of performance and the efficiency curve. Several inflow contours with a ventilated free jet and a conventional flow turbine were studied. The direct comparison of these variants revealed a slightly enhanced peak load efficiency and a very distinct superiority of the free jet contour during partial load. But the efficiency of all variants failed to attain the values claimed by commercial manufacturers. As compared to the initial contour, peak load efficiency was enhanced by 5 per cent. During partial load, the variants studied showed a distinct superiority of the free jet concept over the contour of conventional flow turbines. (orig.) [Deutsch] Am IHS wurde eine ...

1997-12-31

377

Suspension and solution plasma spraying of finely structured layers: potential application to SOFCs  

International Nuclear Information System (INIS)

Suspension direct current plasma spraying allows achieving finely structured coatings whose thickness is between few tens and few hundreds of micrometres. Drops (200-300 ?m in diameter) or liquid jets are mechanically injected in the plasma jet. With radial injection they are rapidly (a few ?s) fragmented into droplets (a few ?m in diameter). The latter are vaporized (in a few ?s) and the solid particles contained in suspension droplets are accelerated and melted by the plasma jet. As in conventional plasma spraying (CPS), much smaller splats (with diameters between 0.2 and 3 ?m and thicknesses between 30 and 200 nm) are arranged in layers up to form the coating. The low inertia of particles requires spray distances between 40 and 60 mm which induces plasma heat fluxes up to 22 MW m-2 participating in coating densification. Even more than in CPS, the plasma jet fluctuations, particularly for plasmas ...

2007-04-21

378

RTD Info 21 - Key Action  

Wastenet

... Targeted fields of research Continuation of ongoing research - Finalising detailed design work on the ITER project; getting JET operational at full power; Improvement of the basic concepts of fusion devices - Fusion plasmas; theoretical studies; technology watch on research into inertial confinement; new experimental concepts and systems; etc.; Long-term technology - Preparations for building a demonstration reactor (development of tritium breeding blankets; prospective ...

379

NO{sub x} formation in lean premixed combustion of methane at high pressures  

Energy Technology Data Exchange (ETDEWEB)

High pressure experiments in a jet-stirred reactor have been performed to study the NO{sub x} formation in lean premixed combustion of methane/air mixtures. The experimental results are compared with numerical predictions using four well known reaction mechanisms and a model which consists of a series of two perfectly stirred reactors and a plug flow reactor. (author) 2 figs., 7 refs.

1999-08-01

380

Hydrocarbon fuels having one or more fullerenes therein as identification media  

Energy Technology Data Exchange (ETDEWEB)

An improved hydrocarbon fuel is described selected from the group consisting of gasoline, diesel fuel, kerosene, jet fuel, No. 1 heating oil, and No. 2 heating oil containing a detectable amount of one or more fullerene additives therein serving as identification means for said fuel wherein said fullerenes are present in an amount insufficient to alter any of the combustion properties of the fuel.

1993-08-10

381

Extratropical Forcing of Convectively Coupled Kelvin Waves during Austral Winter.  

Science.gov (United States)

Observations are presented that link extratropical Rossby wave disturbances excited in the Southern Hemisphere subtropical jet to the initiation of convectively coupled Kelvin waves in the Pacific intertropical convergence zone (ITCZ) during austral winter. A baroclinic, zonal wavenumber 6, eastward-propagating Rossby wave train in the subtropical jet turns northeastward in the vicinity of Australia, inducing upper tropospheric divergence and vertical motion fields that spread equatorward and induce cloudiness anomalies in the Tropics. Lower tropospheric pressure surges excited from the extratropics also induce Kelvin wave-like geopotential height and temperature anomalies at the surface, providing additional lower tropospheric convergence and vertical motion forcing. The tropical outgoing longwave radiation (OLR) and circulation fields propagate eastward in tandem with the extratropical Rossby wave train at approximately 17 m s-1. Kelvin wave ...

2003-02-01

382

Experimental studies of the turbulence structures of impinging reacting jets using time-resolved particle image velocimetry visualisation, hot wire anemometry and acoustic signal processing  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the turbulence structures of premixed impinging jets are investigated by three different experimental techniques: time-resolved particle image velocimetry (TPIV) visualisation, hot wire anemometry (HWA) and acoustic signal processing. The focus is on the TPIV, with the other two techniques providing supplementary information. The 2-D velocities of the impinging jets were obtained by TPIV. The contour maps of velocity derivatives were computed to facilitate the visualisation of the turbulence structure of the reactant part of turbulent impinging flames. Particular attention was concentrated on the turbulence structures out of the burner nozzle and their interactions with the combustion process. It was found that the contour plots are effective in visualising time-dependent structures. It is demonstrated that the derivatives of the velocity field are able to reveal many otherwise hidden turbulence patterns. Test cases were designed ...

2000-12-01

383

Effect of esters on lubricity of hydrotreated jet fuel  

Energy Technology Data Exchange (ETDEWEB)

The authors synthesized a number of esters of stearic acid with polyhydric alcohols and ran comparative tests on aliphatic alcohols to determine their effects on the antiwear properties of the fuel. They conclude that the differences in effectiveness in improving the lubricity by the use of aliphatic alcohols and the full and partial esters of polyhydric alcohols and stearic acid can be explained by the presence of hydroxyl and ester groups close to each other in partial esters. This is reflected in the higher polarity of the partial esters, a higher rate of adsorption, and a stronger bonding of the adsorbed layer to the metal surface.

1985-07-01

384

Development of an efficient, low-NOx domestic gas-range cooktop. Phase 2. Annual report, January 1984-December 1984  

Science.gov (United States)

The objective of the program is to develop a domestic cooktop with low NOx emissions and higher efficiency. During the first phase of the program, a developmental prototype incorporating four IR-Jet burners was assembled. The report describes the work performed during the second phase of the program and covers optimization, and testing of the developmental prototype and design, fabrication and testing of the field-test prototype.

1985-02-01

385

Design basis for protection of light water nuclear power plants against effects of postulated pipe rupture  

Energy Technology Data Exchange (ETDEWEB)

This standard addresses the design bases for light water reactor, nuclear power plant structures and components essential for the protection of public health and safety from the potential adverse effects of pipe whip, jet impingement, pressurization of compartments outside containment, environmental conditions and flooding associated with a postulated pipe rupture. The design bases for missile protection and the design bases for containment pressurization are not within this standard.

1981-01-01

386

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank's structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions ...

1992-01-01

387

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank`s structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions expected to ...

1992-01-01

388

Composite vector leptoquarks in e"+e-, #gamma#e, and #gamma##gamma# colliders  

International Nuclear Information System (INIS)

We study the signals for composite vector leptoquarks in e"+e- colliders (CERN e"+e- collider LEP II, Next Linear Collider, and CERN Linear Collider) through their effects on the production of jet pairs, as well as their single and pair productions. We also analyze their production in #gamma#e and #gamma##gamma# collisions.

389

American National Standard: design basis for protection of light water nuclear power plants against effects of postulated pipe rupture  

Energy Technology Data Exchange (ETDEWEB)

This standard addresses the design bases for light water reactor, nuclear power plant structures and components essential for the protection of public health and safety from the potential adverse effects of pipe whip, jet impingement, pressurization of compartments outside containment, environmental conditions and flooding associated with a postulated pipe rupture. The design bases for missile protection and the design bases for containment pressurization are not within this standard.

1980-12-31

390

The use of dynamic adaptive chemistry in combustion simulation of gasoline surrogate fuels  

Energy Technology Data Exchange (ETDEWEB)

A computationally efficient dynamic adaptive chemistry (DAC) scheme is described that permits on-the-fly mechanism reduction during reactive flow calculations. The scheme reduces a globally valid full mechanism to a locally, instantaneously applicable smaller mechanism. Previously we demonstrated its applicability to homogeneous charge compression ignition (HCCI) problems with n-heptane [L. Liang, J.G. Stevens, J.T. Farrell, Proc. Combust. Inst. 32 (2009) 527-534]. In this work we demonstrate the broader utility of the DAC scheme through the simulation of HCCI and shock tube ignition delay times (IDT) for three gasoline surrogates, including two- and three-component blends of primary reference fuels (PRF) and toluene reference fuels (TRF). Both a detailed 1099-species mechanism and a skeletal 150-species mechanism are investigated as the full mechanism to explore the impact of fuel complexity on the DAC ...

2009-07-15

391

Launching proton-dominated jets from accreting Kerr black holes: the case of M87  

Science.gov (United States)

A general relativistic model for the formation and acceleration of lowmass-loaded jets from systems containing accreting black holes is presented. The model is based on previous numerical results and theoretical studies in the Newtonian regime, but modified to include the effects of space-time curvature in the vicinity of the event horizon of a spinning black hole. It is argued that the boundary layer between the Keplerian accretion disk and the event horizon is best suited for the formation and acceleration of the accretion-powered jets in active galactic nuclei and micro-quasars. The model presented here is based on matching the solutions of three different regions: i- a weakly magnetized Keplerian accretion disk in the outer part, where the transport of angular momentum is mediated through the magentorotational instability, ii- a strongly magnetized, advection-dominated and turbulent-free boundary layer (BL) between the outer cold accretion ...

2011-07-01

392

The PSO support scheme for natural gas - subsidy to industry or environmental policy  

International Nuclear Information System (INIS)

Some aspects of the PSO scheme for natural gas are examined critically. Two central arguments used for justifying the PSO subsidy scheme of natural gas and its distribution are reviewed; these include the 'smallholder argument' and the 'environmental argument'. The 'smallholder argument' claims that since Norway has the natural gas resources, it should also make use of the natural gas in the country, and not simply send the raw material to other countries. The 'environmental argument' states that natural gas compared to other fossil fuels such as coal and fuel oil, is a far cleaner alternative, thus an environmental-friendly alternative entitled to financial support. The arguments are critically examined by the author (ml)

2006-01-01

393

Study of "1"0"1Mo decay  

International Nuclear Information System (INIS)

The decay of "1"0"1Mo to levels in "1"0"1Tc has been studied using the three-parameter (#gamma#-#gamma#-t) coincidence system of HpGe-HpGe detectors. From the coincidence data, the new decay scheme was constructed. The previously reported 104.70, 105.95 and 774.15 keV #gamma# rays were observed, and have been assigned to the decay scheme for the first time. A newly observed 1508.01 keV #gamma# ray has also been assigned to the scheme for the first time. The intensities of #beta#"- and the values of log ft to most levels were calculated

2000-04-01

394

On the two weighting scheme for {delta}f collisional transport simulation  

Energy Technology Data Exchange (ETDEWEB)

The validity is given to the newly proposed two weighting {delta}f scheme (Wang et al., Research Report of National Institute for Fusion Science NIFS-588, 1999) for collisional or neoclassical transport calculations, which can solve the drift kinetic equation taking account of effects of steep plasma gradients, large radial electric field, finite banana width, and the non-standard orbit topology near the axis. The marker density functions in weight equations are successively solved by using the idea of {delta}f method and a hierarchy of equations for weight and marker density functions is obtained. These hierarchy equations are solved by choosing an appropriate source function for each marker density. Thus the validity of the two weighting {delta}f scheme is mathematically proved. (author)

1999-08-01

395

Multiparty controlled quantum secure direct communication using Greenberger Horne Zeilinger state  

Science.gov (United States)

Based on the idea of dense coding of three-photon entangled state and qubit transmission in blocks, we present a multiparty controlled quantum secret direct communication scheme by using Greenberger Horne Zeilinger state. In the present scheme, the sender transmits three bits of secret message to the receiver directly and the secret message can only be recovered by the receiver under the permission of all the controllers. All three-photon entangled states are used to transmit the secret message except those chosen for eavesdropping check and the present scheme has a high source capacity because Greenberger Horne Zeilinger state forms a large Hilbert space.

2006-10-01

396

Index structures for structured documents  

Energy Technology Data Exchange (ETDEWEB)

Much research has been carried out in order to manage structured documents such as SGML documents and to provide powerful query facilities which exploit document structures as well as document contents. In order to perform structure queries efficiently in a structured document management system, an index structure which supports fast document element access must be provided. However, there has been little research on the index structures for structured documents. In this paper, we propose various kinds of new inverted indexing schemes and signature file schemes for efficient structure query processing. We evaluate the storage requirements and disk access time of our schemes and present the analytical and experimental results.

1996-12-31

397

Forming the COUNCIL Based Clusters in Securing Wireless Ad Hoc Networks  

CERN Document Server

In cluster-based routing protocol (CBRP), two-level hierarchical structure is successfully used to reduce over-flooding in wireless Ad Hoc networks. As it is vulnerable to a single point of failure, we propose a new adaptive distributed threshold scheme to replace the cluster head by a group of cluster heads within each cluster, called COUNCIL, and distribute the service of single cluster head to multiple cluster heads using (k,n) threshold secret sharing scheme. An Ad Hoc network formed by COUNCIL based clusters can work correctly when the number of compromised cluster heads is smaller than k. To implement this adaptive threshold scheme in wireless Ad Hoc Networks, membership of the clusters should be defined in an adaptive way. In this paper, we mainly discuss our algorithm for forming COUNCIL based clusters using the concept of dominating set from graph theory.

2010-01-01

398

Feasibility analysis for attosecond X-ray pulses at FERMI@ELETTRA free electron laser  

Energy Technology Data Exchange (ETDEWEB)

We present preliminary analysis for the feasibility of the attosecond x-ray pulses at a proposed FERMI@ELETTRA free electron laser (FEL) [1]. In part 1 we restrict ourselves to minimal modifications to the proposed FEL and consider a scheme for attosecond x-ray production which can be qualified as a small add-on to a primary facility. We demonstrate that at 5-nm wavelength our scheme is capable for production of pulses with an approximate duration of 100 attoseconds at approximately 2 MW peak power and with an absolute temporal synchronization to a pump laser pulse. In part 2 we propose to use an FEL amplifier seeded by a VUV signal and to follow it by the scheme for attosecond x-ray production described in part 1.

2004-09-01

399

Effects of boron pollution in the lower buyuk menderes basin (Turkey) on agricultural areas and crops  

British Library Electronic Table of Contents (United Kingdom)

Abstract The aim of this study is to study the effects of Boron (B) pollution in Buyuk Menderes river on planted crops and agricultural areas constructed in the irrigation schemes by the State Hydraulic Works (DSI) of the Lower Buyuk Menderes basin, Turkey. The studied irrigation schemes in the basin are Saraykoy, Pamukkale, Nazilli, Aydin, Sultanhisar, Koarli, and Soke. Mean B concentrations of river water used in the irrigation schemes ranged from 0.10 to 0.43 mgB L-1 for the period of 2008 to 2009. A total of 100,556 ha of the agricultural area and the basin groundwater resources are under the influence of B pollution from the Buyuk Menderes river. The amount of B accumulating in soils and seepage in the groundwater due to the used irrigation water was 18,495,350 and 9153 kgB yr-1, resp...

2011-01-01

400

Development of a 1D neutron transport code employing the method of characteristics  

International Nuclear Information System (INIS)

To investigate the 2D/1D fusion core analysis method, a 1D neutron transport problem solver, PEACH-ID, is developed. It is a code of method of characteristics (MOC), both the usual fiat-source step characteristics (SC) scheme and linear source (LS) approximation scheme are adopted for tracking calculation along the neutron flying trajectory. Exponential function interpolation table and fission source extrapolation are adopted as two major methods to accelerate the computational process. Numerical results demonstrate that PEACH-1D is accurate and efficient, and the proposed LS scheme is able to handle quite larger mesh division and deserves much more application in the MOC codes. (authors)

2009-09-01

401

Development of Control Design Scheme Using Nonlinear Analysis  

Science.gov (United States)

Phenomena in power systems tend to exhibit higher nonlinearity, because efficient operation accompanies severer power transfer. In such cases, there might exist some limitation to the use of conventional linear control design scheme due to the nonlinearity. As for consideration to the nonlinearity, we have developed a nonlinear analysis method based on normal form theory. In this paper, we develop a new control design scheme based on the nonlinear analysis method. The developed method is effective in a case when oscillatory instability occurs. In the developed method, the parameters of control devices are adjusted so as to enlarge the stability limit against the oscillatory instability, unless each eigenvalue exceed its allowable threshold. We verify the effectiveness of the developed method in the IEEJ 10-machine System Model by applying to PSS (Power System Stabilizer). We show that the power transfer limit increases by a few percent.

2007-01-01

402

Decays of "8"8Kr and "8"8Rb  

International Nuclear Information System (INIS)

The #gamma# rays following the #beta# decays of "8"8Kr and "8"8Rb have been studied, using both large volume Ge(Li) detectors for singles and coincidence measurements and anti-Compton spectrometry for singles measurements. Level schemes for "8"8Rb and "8"8Sr were constructed from the data and 74 of 81 #gamma# rays observed in the decay of "8"8Kr were placed in the "8"8Rb level scheme with 23 excited states. For the decay of "8"8Rb, all of the observed 27 #gamma# rays have been placed in the (well known) level structure of "8"8Sr. Spin and parity assignments have been deduced from #beta#-decay logft values and #gamma#-ray transition patterns. Possible shell model interpretations are presented for the level schemes.

403

Computational experience with an explicit difference scheme for a one phase Stefan problem  

Science.gov (United States)

The results of a computational scheme of Rose (a method for calculating solutions of parabolic equations with free boundary, Math. Comp., 14: 249-256(1960)) are compared with the known analytic solution of a single-phase Stefan problem with constant boundary temperature. Rose's scheme was implemented in FORTRAN on a DEC PDP-10. Computations were performed for Stefan numbers St = 0.01, 0.1, 1, 10, and 100. Three relative mesh sizes (..gamma.. = DT/(DX)/sup 2/ = 1/2, 1/6, and 1/25) were used. For each St, the relative mesh size had very little effect on accuracy. However, taking ..gamma.. = 1/25 resulted in dramatically increased computing time. The relative errors of temperature were large near the phase change front. 11 figures, 5 tables.

1980-07-01

404

Comparison of Galerkin and control volume finite element for advection-diffusion problems.  

Energy Technology Data Exchange (ETDEWEB)

The control volume finite element method (CVFEM) was developed to combine the local numerical conservation property of control volume methods with the unstructured grid and generality of finite element methods (FEMs). Most implementations of CVFEM include mass-lumping and upwinding techniques typical of control volume schemes. In this work we compare, via numerical error analysis, CVFEM and FEM utilizing consistent and lumped mass implementations, and stabilized Petrov-Galerkin streamline upwind schemes in the context of advection-diffusion processes. For this type of problem, we find no apparent advantage to the local numerical conservation aspect of CVFEM as compared to FEM. The stabilized schemes improve accuracy and degree of positivity on coarse grids, and also reduce iteration counts for advection-dominated problems.

2005-03-01

405

Catalytic oxidative conversion of alkanes to olefines and oxygenates  

Energy Technology Data Exchange (ETDEWEB)

All of the direct reaction schemes described and the corresponding process schemes are still in an exploratory state. Ethylene by oxidative coupling of methane could become competitive if process schemes are developed with significantly less expenditures for separation of the product from unconverted feed. No encouragement for formaldehyde from methane can be presently derived from the existing knowledge. Liquid-phase oxidation of methane to methanol appears to be attractive but no final judgement is possible at present. Oxidative dehydrogenation of ethylene and propane look promising although further catalyst improvement is required. Acetic acid from ethane and acrylonitrile from propane have a certain potential as an alternative to present technology. The outlook for acrolein and acrylic acid from propane is less favourable; new concepts for catalyst design are necessary. (orig.)

1998-12-31

406

An efficient quantum secure direct communication scheme with authentication  

Science.gov (United States)

In this paper an efficient quantum secure direct communication (QSDC) scheme with authentication is presented, which is based on quantum entanglement and polarized single photons. The present protocol uses Einstein-Podolsky-Rosen (EPR) pairs and polarized single photons in batches. A particle of the EPR pairs is retained in the sender's station, and the other is transmitted forth and back between the sender and the receiver, similar to the ``ping-pong'' QSDC protocol. According to the shared information beforehand, these two kinds of quantum states are mixed and then transmitted via a quantum channel. The EPR pairs are used to transmit secret messages and the polarized single photons used for authentication and eavesdropping check. Consequently, because of the dual contributions of the polarized single photons, no classical information is needed. The intrinsic efficiency and total efficiency are both 1 in this scheme as almost all of the ...

2007-07-01

407

The EU as a frontrunner on greenhouse gas emissions trading. How did it happen and will the EU succeed?  

Energy Technology Data Exchange (ETDEWEB)

The objective of this paper is first to provide empirical evidence of what can be seen as a rather remarkable change in EU's position on the use of greenhouse gas (GHG) emissions trading (ET) in climate policy, from the role of a sceptic in the run-up to Kyoto towards more of a frontrunner. The paper argues that there is a synergistic and multilevel mix of explanatory factors for this 'U-turn', including developments at the international, EU, Member State, sub-national, and even down to the personal level. Second, the paper explores and discusses the philosophy behind the Commission's proposal for a directive on GHG ET. Third, the paper examines the prospects for 'success' of a scheme for EU-wide ET using a multifaceted set of metrics. In brief, we argue that output success - the chances for having a directive adopted - hinges on the resolution of two key issues. First, whether the preliminary phase is to be ...

2003-07-01

408

Terminal-differential algorithm for identification of local non homogeneity in article  

International Nuclear Information System (INIS)

Terminal-differential algorithm for identification of local nonhomogeneities in items under control is developed on the basis of measurements of X-ray or gamma-radiation weakening. The algorithm may be applied by developing radiation schemes of nondestructive control, identifying inadmissible inclusions in the object under study

409

Seal is successful at Italys largest pumped storage plant  

British Library Electronic Table of Contents (United Kingdom)

A HydroSele S seal from James Walker has provided more than two years maintenance-free service at the large Entracque pumped-storage hydroelectric scheme in Italy.

2008-01-01

410

Remote environmental monitoring at No. 26 Colliery  

Energy Technology Data Exchange (ETDEWEB)

The author describes the layout of the environmental monitoring scheme at Devco's No. 26 Colliery in Canada, which includes wall face ventilation, fan performance, and methane drainage monitoring. He gives details of the sensors, outstations, and the surface control room.

1982-03-01

411

Relativistic Feynman-type integrals  

Energy Technology Data Exchange (ETDEWEB)

It is shown that within the framework of the Kershaw stochastic model generalized by the author to the relativistic case a Feynman-type process may be constructed which can formally be understood as a diffusion phenomenon in Euclidean space. This makes it possible to introduce a real probability measure in the scheme of quantum mechanics proposed by Feynman.

1980-05-01

412

On the decay of "2"0"3Bi  

International Nuclear Information System (INIS)

The radioactive decay of "2"0"3Bi is studied. A level scheme is proposed for "2"0"3Pb on the basis of #gamma#-ray and electron spectra and #gamma#-#gamma# coincidence measurements. The experimental data are compared with theoretical results obtained in a three quasiparticle approximation. (Auth.).

413

Nuclear data sheets for A = 242  

Energy Technology Data Exchange (ETDEWEB)

Detailed level and decay schemes and the experimental reaction and decay data on which they are based are presented for nuclei with mass number A = 242; the experimental data are evaluated. Adopted values for level and ..gamma..-ray energies, ..gamma..-intensities, as well as other nuclear properties are given.

1985-07-01

414

Nuclear data sheets for A = 242  

International Nuclear Information System (INIS)

Detailed level and decay schemes and the experimental reaction and decay data on which they are based are presented for nuclei with mass number A = 242; the experimental data are evaluated. Adopted values for level and #gamma#-ray energies, #gamma#-intensities, as well as other nuclear properties are given.

415

Nuclear Data Sheets for A = 88  

Energy Technology Data Exchange (ETDEWEB)

The 1976 version of Nuclear Data Sheets for A = 99 (76Bu07) has been revised. Detailed level and decay schemes, arguments for J..pi.. assignments, and experimental data are presented. copyright 1988 Academic Press, Inc.

1988-05-01

416

Nuclear Data Sheets for A = 88  

International Nuclear Information System (INIS)

The 1976 version of Nuclear Data Sheets for A = 99 (76Bu07) has been revised. Detailed level and decay schemes, arguments for J#pi# assignments, and experimental data are presented. copyright 1988 Academic Press, Inc.

417

Neutron stars in massive binary systems. I. Classification and evolution  

Energy Technology Data Exchange (ETDEWEB)

A study of the joint evolution of the normal- and neutron-star components of massive binaries opens with a classification scheme and the analytic expressions to be applied in Paper II for computer simulation of the observable properties of such systems.

1983-03-01

418

Modular control of human walking: Adaptations to altered mechanical demands  

UK PubMed Central (United Kingdom)

Studies have shown that the nervous system may adopt a control scheme in which synergistic muscle groups are controlled by common excitation patters, or modules, to simplify the coordination...Full Text Available

2010-02-10

419

Hydrogen in metals  

International Nuclear Information System (INIS)

An important application of metal hydrides is as a moderator material in nuclear reactors. The fundamental properties of hydrides are illustrated and an impression given of the current research into hydrogen in transition metals. Phase diagrams, magnetic properties, temperature dependence of the diffusion coefficient, energy level schemes and superconductivity are considered. (C.F.).

420

Generalized support varieties for finite group schemes  

CERN Document Server

We construct two families of refinements of the (projectivized) support variety of a finite dimensional module $M$ for a finite group scheme $G$. For an arbitrary finite group scheme, we associate a family of {\\it non maximal rank varieties} $\\Gamma^j(G)_M$, $1\\leq j \\leq p-1$, to a $kG$-module $M$. For $G$ infinitesimal, we construct a finer family of locally closed subvarieties $V^{\\ul a}(G)_M$ of the variety of one parameter subgroups of $G$ for any partition $\\ul a$ of $\\dim M$. For an arbitrary finite group scheme $G$, a $kG$-module $M$ of constant rank, and a cohomology class $\\zeta$ in $\\HHH^1(G,M)$ we introduce the {\\it zero locus} $Z(\\zeta) \\subset \\Pi(G)$. We show that $Z(\\zeta)$ is a closed subvariety, and relate it to the non-maximal rank varieties. We also extend the construction of $Z(\\zeta)$ to an arbitrary extension class $\\zeta \\in \\Ext^n_G(M,N)$ whenever $M$ and $N$ are $kG$-modules of ...

2011-01-01

421

Full-Rate Full-Diversity Achieving MIMO Precoding with Partial CSIT  

CERN Document Server

In this paper, we consider a $n_t\\times n_r$ multiple-input multiple-output (MIMO) channel subjected to block fading. Reliability (in terms of achieved diversity order) and rate (in number of symbols transmitted per channel use) are of interest in such channels. We propose a new precoding scheme which achieves both full diversity ($n_tn_r$th order diversity) as well as full rate ($n_t$ symbols per channel use) using partial channel state information at the transmitter (CSIT), applicable in MIMO systems including $n_rscheme achieves full diversity and improved coding gain through an optimization over the choice of constellation sets. The optimization maximizes $d_{min}^2$ for our precoding scheme subject to an energy constraint. The scheme requires feedback of $n_t-1$ angle parameter values, compared to $2n_tn_r$ real coefficients in case of full CSIT. Error rate ...

2011-01-01

422

Dynamic Rating and Underground Monitoring System (DRUMS)  

Energy Technology Data Exchange (ETDEWEB)

Drums is an acronym for Dynamic Rating and Underground Monitoring System, with specific application to high-pressure pipe-type cable systems which are the predominant means of underground electric power transmission in the United States. The primary objective of this EPRI-sponsored feasibility study was to establish the technical feasibility of seven DRUMS functions and two novel DRUMS communication schemes. The seven DRUMS functions which monitor the system's vital and measurable parameters in real time and perform system diagnostics in the event of component deterioration, malfunction or failure are: Real Time Current Monitoring and Rating; Leak Detection and Location; Fault Location; Pothead Monitoring; Oil Monitoring; Pipe Protection; and Splice Monitoring. The two DRUMS communication schemes are internal to the pipe cable system. Mechanical Communication will use pressure pulses to transmit data along the system, while the ...

1991-07-01

423

Cracking resistance in steam pipe fittings having various microdamage levels  

Energy Technology Data Exchange (ETDEWEB)

Cracking resistance and metal damage are considered in relation to structural state for steam-pipe fittings during use. An approximate scheme is given for estimating the maximum permissible operating time in the plastic state in relation to the depth of an observed crack-type defect.

1995-05-01

424

A Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties  

Science.gov (United States)

We propose a simultaneous quantum secure direct communication scheme between one party and other three parties via four-particle GHZ states and swapping quantum entanglement. In the scheme, three spatially separated senders, Alice, Bob and Charlie, transmit their secret messages to a remote receiver Diana by performing a series of local operations on their respective particles according to the quadripartite stipulation. From Alice, Bob, Charlie and Diana's Bell measurement results, Diana can infer the secret messages. If a perfect quantum channel is used, the secret messages are faithfully transmitted from Alice, Bob and Charlie to Diana via initially shared pairs of four-particle GHZ states without revealing any information to a potential eavesdropper. As there is no transmission of the qubits carrying the secret message in the public channel, it is completely secure for the direct secret communication. This scheme can be ...

2005-10-01

425

A Robust and Efficient Trust Management Scheme for Peer-to-Peer Networks  

CERN Document Server

Studies on the large scale peer-to-peer (P2P) network like Gnutella have shown the presence of large number of free riders. Moreover, the open and decentralized nature of P2P network is exploited by malicious users who distribute unauthentic or harmful contents. Despite the existence of a number of trust management schemes in the literature for combating against free riding and distribution of malicious files, these mechanisms are not scalable due to their high computational, communication and storage overhead. These schemes also do not consider effect of trust management on quality-of-service (QoS) of the search. This paper presents a trust management scheme for P2P networks that minimizes distribution of spurious files by a novel technique called topology adaptation. It also reduces search time since most of the queries are resolved within the community of trustworthy peers. Simulation results indicate that the trust ...

2010-01-01

426

Waste management considerations for fusion power reactors  

International Nuclear Information System (INIS)

To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.

427

Waste management considerations for fusion power reactors  

Science.gov (United States)

To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.

1978-02-01

428

Viscoelastic locally resonant double negative metamaterials with controllable effective density and elasticity  

British Library Electronic Table of Contents (United Kingdom)

A metamaterial that is composed of solid viscoelastic elements with controllable properties is proposed in this Letter. This enables an adaptable and general acoustic metamaterial to be practically realised. An array of masses with a single elastic connection to a supporting viscoelastic structure, such as one that is dynamically equivalent to an array of Helmholtz resonators, only provides a system with negative effective mass. A local active control scheme applied to each of these masses can emulate additional elastic connections to the supporting structure. An array of masses with a suitable local control scheme can provide both the negative effective stiffness and mass required for negative refraction. The tuneable feedback control parameters determine the characteristics of the region...

2010-01-01

429

The Geometry of Stable Quotients in Genus One  

CERN Document Server

Stable quotient spaces provide an alternative to stable maps for compactifying spaces of maps. When the target is projective space and the domain curve has genus 1, these are smooth proper Deligne-Mumford stacks. In this paper we study the associated coarse moduli schemes. We show these schemes are projective, rationally connected and have Picard number 2. Then we give generators for the Picard group, compute the canonical divisor, and the cones of ample and effective divisors. In certain cases, we also give a closed formula for the Poincar\\'{e} polynomial.

2011-01-01

430

Spiral Structure in IP Peg Confronting Theory and Observations  

CERN Document Server

Steeghs et al. (1997) have found the first convincing evidence for spiral structure in the accretion disc in IP Pegasi. We perform two kinds of 2D hydrodynamic simulations, a SFS finite volume scheme and a SPH scheme, in the case of mass ratio of 0.5. Both results agree well each other. We construct the Doppler maps and line flux-binary phase relation based on the density distributions. Both of our results agree well with those obtained by the observation.

1998-01-01

431

Solution of vector Stefan problems with cross-diffusion  

Science.gov (United States)

A general model for the dissolution of particles in multi-component alloys is proposed and analyzed. The model is based on diffusion equations with cross-terms for the several species, combined with a Stefan condition as the equation of motion of the interface between the particle and diffusive phase. Several numerical schemes for the solution of the Stefan problem are proposed and compared. It turns out that diagonalization is useful for numerical purposes. However, for the case of position-dependent diffusion coefficients one has to use a different scheme. Here, we analyze stability and workload of several time integration methods.

2005-04-01

432

Self-optimized Coverage Coordination and Coverage Analysis in Femtocell Networks  

CERN Document Server

This paper proposes a self-optimized coverage coordination scheme for two-tier femtocell networks, in which a femtocell base station adjusts the transmit power based on the statistics of the signal and the interference power that is measured at a femtocell downlink. Furthermore, an analytic expression is derived for the coverage leakage probability that a femtocell coverage area leaks into an outdoor macrocell. The coverage analysis is verified by simulation, which shows that the proposed scheme provides sufficient indoor femtocell coverage and that the femtocell coverage does not leak into an outdoor macrocell.

2009-01-01

433

Quantum Computation with Nonlinear Optics  

International Nuclear Information System (INIS)

We propose a scheme of quantum computation with nonlinear quantum optics. Polarization states of photons are used for qubits. Photons with different frequencies represent different qubits. Single qubit rotation operation is implemented through optical elements like the Faraday polarization rotator. Photons are separated into different optical paths, or merged into a single optical path using dichromatic mirrors. The controlled-NOT gate between two qubits is implemented by the proper combination of parametric up and down conversions. This scheme has the following features: (1) No auxiliary qubits are required in the controlled-NOT gate operation; (2) No measurement is required in the course of the computation; (3) It is resource efficient and conceptually simple.

2008-01-15

434

Practical purification scheme for decohered coherent-state superpositions via partial homodyne detection  

International Nuclear Information System (INIS)

We present a simple protocol to purify a coherent-state superposition that has undergone a linear lossy channel. The scheme constitutes only a single beam splitter and a homodyne detector, and thus is experimentally feasible. In practice, a superposition of coherent states is transformed into a classical mixture of coherent states by linear loss, which is usually the dominant decoherence mechanism in optical systems. We also address the possibility of producing a larger amplitude superposition state from decohered states, and show that in most cases the decoherence of the states are amplified along with the amplitude.

2006-04-01

435

On the validity of the pseudo-spin concept for axially symmetric deformed nuclei  

International Nuclear Information System (INIS)

The average single-particle field shows a very small pseudo-spin-orbit splitting in the pseudo-spin representation. If this splitting is neglected, pseudo-spin becomes a good quantum number and the resulting scheme (the pseudo-Nilsson model) has a very simple interpretation. The pseudo-spin symmetry embodied in the realistic deformed average field is explored by comparing the single-particle energies and wave functions of the deformed Woods-Saxon model with the corresponding results of the pseudo-Nilsson model. The scheme is used to calculate the magnetic moments of deformed odd-A nuclei of the rare-earth region. (orig.).

436

On the Reduction of Broadcast Traffic in Mobile Ad Hoc Networks  

CERN Document Server

Many mobile ad hoc network protocols use simple flooding, in order to adapt to changes in time varying network topology. Most of the times, a network-wide flood results in redundant packets and increases network congestion, probability of packet collision, low utilization of available bandwidth, and most important, higher power consumption. In this paper, we propose a new cross-layer broadcast scheme to minimize broadcast traffic in mobile ad hoc networks. Our scheme is based on use of received signal strength indicator, RSSI, value to reduce the number of broadcast packets. The effectiveness of the proposed technique is verified using simulations.

2010-01-01

437

Measurement of low-energy laser pulse duration in femtosecond range  

International Nuclear Information System (INIS)

Measurements of low-energy (#approx#10"- "1"0 J) femtosecond laser pulse durations have been carried out on the basis of second-order autocorrelation function analysis. The scheme of non collinear second harmonic generation realized in KDP crystal has been used for increasing of the measurement contrast and accuracy. Proposed scheme can be used for measurements in wide enough ranges of laser pulse durations (from tens femto seconds to hundreds picoseconds) and energies. (authors)

438

Investigation of the "1"0"1Mo level and gamma-decay scheme by thermal neutron capture in "1"0"0Mo  

International Nuclear Information System (INIS)

The #gamma#-radiation following thermal neutron capture in "1"0"0Mo has been studied by singles and coincidence measurements. A "1"0"1Mo level scheme has been deduced and is compared with the results of previous (d,p), (n,#gamma#) and "1"0"1Nb decay studies. The existence of the first excited state at 13.51 keV has been confirmed. The present data yield a neutron binding energy of 5398.4 KeV. (Auth.).

1975-03-01

439

Integrated photonic qubit quantum computing on a superconducting chip  

International Nuclear Information System (INIS)

We study a quantum computing system using microwave photons in transmission line resonators on a superconducting chip as qubits. We show that linear optics and other controls necessary for quantum computing can be implemented by coupling to Josephson devices on the same chip. By taking advantage of the strong nonlinearities in Josephson junctions, photonic qubit interactions can be realized. We analyze the gate error rate to demonstrate that our scheme is realistic even for Josephson devices with limited decoherence times. As a conceptually innovative solution based on existing technologies, our scheme provides an integrated and scalable approach to the next key milestone for photonic qubit quantum computing.

2010-06-01

440

Inclusive photoproduction of D{sup *{+-}} mesons at next-to-leading order in the general-mass variable-flavor-number scheme  

Energy Technology Data Exchange (ETDEWEB)

We discuss the inclusive production of D{sup *{+-}} mesons in {gamma}p collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavor-number scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We present detailed numerical results for a comparison with data obtained at HERA and discuss various sources of theoretical uncertainties. (orig.)

2009-02-15

441

In-beam spectroscopy of nuclei  

International Nuclear Information System (INIS)

The main features and advantages of a new low energy nuclear spectroscopic method, the in-beam spectroscopy are described. Results of in-beam spectroscopic experiments performed at the Institute of Nuclear Research (ATOMKI, Debrecen, Hungary) are summarized. Gamma spectra of in-beam produced odd-odd nuclei were measured, gamma-energies were determined. Measurement of gamma-gamma coincidences led to the construction of energy level schemes of the investigated nuclei. Internal conversion electron spectroscopy was used to determine the multipolarities of transitions. A few spectra and level schemes are presented to illustrate the review. Theoretical interpretation of experimental results are briefly summarized. (D.Gy.).

1982-01-01

442

Fundamentals for remote structural health monitoring of wind turbine blades - a pre-project. Annex B - Sensors and non-destructive testing methods for damage detection in wind turbine blades  

Energy Technology Data Exchange (ETDEWEB)

This annex provides a description of the sensor schemes and the non-destructive testing (NDT) methods that have been investigated in this project. Acoustic emission and fibre optic sensors are described in some detail whereas only the key features of well-established NDT methods are presented. Estimates of the cost of different sensor systems are given and the advantages and disadvantages of the different schemes is discussed. (au)

2002-05-01

443

Efficient quantum secure communication scheme with one-time pad  

Science.gov (United States)

In this paper, we proposed a novel quantum secure direct communication scheme with one-time pad in stabilizer formalism. Based on the reuse of qubit sequence, an efficient secure communication of secret messages without first producing a shared secret key can be achieved. One hence may find that the amount of private key needed for quantum communication is smaller than that in the general case. Therefore, the present protocol which is feasible with the present-day techniques may be applied to quantum communication with short-length encoding.

2009-05-01

444

Decay study of the "1"1"7Cs and "1"1"7Xe nuclei  

International Nuclear Information System (INIS)

Gamma-rays and conversion electrons emitted in the "1"1"7Cs and "1"1"7Xe decays have been studied from on-line mass-separated "1"1"7Cs sources at the ISOLDE facility. A new "1"1"7Xe decay scheme has been constructed and a level scheme has been established for the "1"1"7Cs decay. The results are discussed in the frame of our recent knowledge about odd-mass neutron-deficient I and Xe systematics.

1982-09-01

445

Contribution to the compensation of extra high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

An improved method to design suitable compensating schemes for extra high voltage transmission lines is presented. The technique is general and effective and will greatly facilitate the design of the optimal compensation scheme for extra high voltage transmission lines. The technique is illustrated for a typical 500 kV system. The equations developed here for voltage maxima and minima along the transmission line eliminate the need for point-to-point computation of the voltage profile. The controversy existing in the literature over the problem of making a choice between pi and tee configurations has been removed and it is established with a mathematical proof that the tee configuration requires compensating elements of lower ratings.

1987-04-01

446

Coal preparation plant condition-based maintenance  

Energy Technology Data Exchange (ETDEWEB)

This report briefly describes the background to colliery engineering maintenance, past experience in machine condition monitoring within coal preparation and the introduction of condition-based maintenance. A role model scheme has been developed for the introduction of condition-based maintenance into coal preparation plants. The report describes the instrumentation and monitoring methods suitable for application to most mineral processing plants, the use of specialist companies to monitor, gather, process and analyse the information and the actions taken by the colliery. Examples of the benefits of operating such a scheme are given in terms of safety, performance and finance. Other problematical aspects of coal processing are examined which have a direct effect on plant condition and availability.

1998-12-31

447

Approximation of a Fractional Order System by an Integer Order Model Using Particle Swarm Optimization Technique  

CERN Document Server

System identification is a necessity in control theory. Classical control theory usually considers processes with integer order transfer functions. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme is presented for approximation of such a real world fractional order process by an ideal integral order model. A population of integral order process models is generated and updated by PSO technique, the fitness function being the sum of squared deviations from the set of observations obtained from the actual fractional order process. Results show that the proposed scheme offers a high degree of accuracy.

2008-01-01

448

A new scheme of the longitudinal emittance measurement for negative ion beams  

Energy Technology Data Exchange (ETDEWEB)

A new scheme of the longitudinal emittance measurement for high energy negative ion beam is proposed. The energy distribution of the detached electron from the negative ions by the photodetachment process, if the photon energy is almost equal to the electron binding energy of the negative ion (=electron affinity of the atom), reflects that of the original negative ions. Therefore, by introducing the photon in a short width comparing with the bunch width of the negative ion beam, the longitudinal energy distribution of each phase of the beam, that is the longitudinal emittance, can be measured. (author).

1995-08-01

449

Unburned hydrocarbon under light load conditions in a direct injection diesel engine. 1st Report. ; HC emission in long idling operation. Chokusetsu funshashiki diesel kikan no keifuka untenji no minen tanka suiso. 1. ; Chojikan idle untenji no haishutsu tokusei  

Energy Technology Data Exchange (ETDEWEB)

Discussions were given on the characteristics of a diesel engine to emit unburned hydrocarbon (HC) created in a long idling operation. The engine tested in the experiment is a direct injection diesel engine with six water-cooled were investigated varying the jet hole diameter and length of the jet nozzle. In the initial operation period, the HC showed high values. This is thought because part of the injected fuel has deposited on the wall because of low combustion chamber wall temperature, and the fuel deposit that did not evaporate during combustion evaporated during expansion process and emitted unburned. The head was dismantled to investigate the carbon flowers deposited on the nozzle and the relationship between the carbon and the HC deposited on the head face and the combustion chamber wall. It was clarified that the HC increase was phenomenal compared with that of the carbon. This is because the injected fuel was adsorbed into the carbon, ...

1992-04-01

450

Two-phase flow regime transition criteria in post-dryout region based on flow visualization experiments  

Energy Technology Data Exchange (ETDEWEB)

A visual study of film boiling using photographic and high speed motion-picture methods was carried out to determine the flow regime transition criteria in the post-CHF region. An idealized inverted annular flow was obtained by introducing a liquid jet of Freon 113 through a nozzle, precisely centered with respect to the internal diameter of the test section, with an annular gas flow. The respective ranges for liquid and gas exit velocities were 0.05 to 0.5 and 0.03 to 7.9 m/s. Nitrogen and helium were used in the study. For the present configuration, there are four basic flow regimes. Beginning from the nozzle exit, there is a smooth, inverted annular flow section with liquid in the core and gas in the annulus; followed by the rough wavy section with an intact liquid core, the agitated and the dispersed flow regimes. For a given liquid jet velocity, the axial extent of each flow regime decreases with increasing gas velocity through the ...

1987-06-01

451

Two-phase flow regime transition criteria in post-dryout region based on flow visualization experiments  

International Nuclear Information System (INIS)

A visual study of film boiling using photographic and high speed motion-picture methods was carried out to determine the flow regime transition criteria in the post-CHF region. An idealized inverted annular flow was obtained by introducing a liquid jet of Freon 113 through a nozzle, precisely centered with respect to the internal diameter of the test section, with an annular gas flow. The respective ranges for liquid and gas exit velocities were 0.05 to 0.5 and 0.03 to 7.9 m/s. Nitrogen and helium were used in the study. For the present configuration, there are four basic flow regimes. Beginning from the nozzle exit, there is a smooth, inverted annular flow section with liquid in the core and gas in the annulus; followed by the rough wavy section with an intact liquid core, the agitated and the dispersed flow regimes. For a given liquid jet velocity, the axial extent of each flow regime decreases with increasing gas velocity through the ...

1987-01-01

452

Transient analysis of blowdown thrust force under PWR LOCA  

Energy Technology Data Exchange (ETDEWEB)

The analytical results of blowdown characteristics and thrust forces were compared with the experiments, which were performed as pipe whip and jet discharge tests under the PWR LOCA conditions. The blowdown thrust forces were obtained by Navier-Stokes momentum equation for a single-phase, homogeneous and separated two-phase flow, assuming critical pressure at the exit if a critical flow condition was satisfied. The following results are obtained: (1) The node-junction method is useful for both the analyses of the blowdown thrust force and of the water hammer phenomena. (2) The Henry-Fauske model for subcooled critical flow is effective for the analysis of the maximum thrust force under the PWR LOCA conditions. The jet thrust parameter of the analysis and experiment is equal to 1.08. (3) The thrust parameter of saturated blowdown has the same one with the value under pressurized condition when the stagnant pressure is chosen as the saturated ...

1983-04-01

453

Toroidal rotation braking with n = 1 magnetic perturbation field on JET  

International Nuclear Information System (INIS)

A strong toroidal rotation braking has been observed in plasmas with application of an n = 1 magnetic perturbation field on the JET tokamak. Calculation results from the momentum transport analysis show that the torque induced by the n = 1 perturbation field has a global profile. The maximal value of this torque is at the plasma core region (#rho# < 0.4) and it is about half of the neutral beam injection torque. The calculation shows that the plasma is mainly in the #nu#_-#sq root##nu# regime in the plasma core, but it is close to the transition between the 1/#nu# and #nu#_-#sq root##nu# regimes. The neoclassical toroidal viscosity (NTV) torque in the 1/#nu# and #nu#_-#sq root##nu# regimes is calculated. The observed torque is of a magnitude in between that of the NTV torque in the 1/#nu# and #nu#_-#sq root##nu# regimes. The NTV torque in the #nu#_-#sq root##nu# regimes is enhanced using the Lagrangian variation of the magnetic field strength. However, it is ...

2010-10-01

454

Top physics: measurement of the tt-bar production cross section in p anti-p collisions at s**(1/2) = 1.96 tev using lepton + jets events with secondary vertex b-tagging  

Energy Technology Data Exchange (ETDEWEB)

We present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96TeV. In these events, heavy flavor quarks from top quark decay are identified with a secondary vertex tagging algorithm. From 162 pb{sup -1} of data collected by the Collider Detector at Fermilab, a total of 48 candidate events are selected, where 13.5 {+-} 1.8 events are expected from background contributions. We measure a t{bar t} production cross section of 5.6{sub -1.1}{sup _1.2}(stat.){sub -0.6}{sup +0.9}(syst.)pb.

2005-04-07

455

The use of high-pressure water jetting to remove the corrosion deposit from samples of the WSGHWR primary circuit pipework  

International Nuclear Information System (INIS)

A series of tests has been carried out to determine the operating conditions required to remove the corrosion deposit from samples cut from Winfrith Steam Generating Heavy Water Reactor (WSGHWR) primary circuit pipework by submerged water jetting. Two types of samples were used - one set subjected to the normal annual reactor decontamination using TURCO reagents, the other set having been given a LOMI treatment in addition. Tests showed that useful decontamination factors could be achieved on both types of sample, but significantly less severe operating conditions were required to decontaminate the LOMI treated samples. A decontamination factor of 10 was achieved on TURCO treated samples at 360 Bar; only 200 Bar was required to achieve the same decontamination factor on LOMI treated samples. No metal erosion of the stainless steel substrate was found to occur at these pressures. (author).

456

Status of he-cooled divertor development (PPCS subtask TW4-TRP-001-D2)  

International Nuclear Information System (INIS)

Within the framework of the EU power plant conceptual study (PPCS), helium-cooled modular divertor concepts have been investigated in detail at the Forschungszentrum Karlsruhe during the past few years. The first conceptual design proposed was based on convective cooling with the use of flow promoters in the form of pin and/or slot arrays (HEMP/HEMS) to increase the cooling surface and, hence, enhance the heat transfer capacity. While continuing the design optimisation, an advanced multiple-jet design (HEMJ) was introduced, which is based on direct jet-to-wall impinging cooling and offers advantages in terms of simple construction and manufacturing. Main emphasis of the 2004 work program (TW4-TRP-001) lay on experiments for the concepts HEMJ and HEMS, which were mainly performed at the Efremov Institute in St. Petersburg, Russia. For experiment preparation, detailed test programs were worked out and accompanying CFD analyses were accomplished. ...

457

RESOLVING DOPPLER-FACTOR CRISIS IN ACTIVE GALACTIC NUCLEI: NON-STEADY MAGNETIZED OUTFLOWS  

International Nuclear Information System (INIS)

Magnetically driven non-stationary acceleration of jets in active galactic nuclei results in the leading parts of the flow being accelerated to much higher Lorentz factors than in the case of steady-state acceleration with the same parameters. The higher Doppler-boosted parts of the flow may dominate the high-energy emission of blazar jets. We suggest that highly variable GeV and TeV emission in blazars is produced by the faster moving leading edges of highly magnetized non-stationary ejection blobs, while the radio data trace the slower-moving bulk flow. Thus, the radio and gamma-ray emission regions have different, but correlated, Doppler factors. High-energy emission is generated, typically within the optically thick core, in the outer parts of the broad-line emission region, avoiding the radiative drag on the faster parts of the flow. The radio emission should correlate with the gamma-ray emission, delayed with frequency-dependent time lag ...

2010-10-10

458

Plasma jet ignition device  

Energy Technology Data Exchange (ETDEWEB)

An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity ...

1985-01-15

459

Nitrogen oxide abatement by distributed fuel addition. Quarterly report No. 8, May 1, 1989--July 31, 1989  

Energy Technology Data Exchange (ETDEWEB)

The performance of the new combustor was tested. Experiments showed that this combustor has superior insulating quality than the previous one. Measured radial concentrations indicated uniform distribution of the primary fuel (coal) inside the fire tube resulting in reasonably flat concentration profiles. However, measured radial concentrations after the addition of the reburn fuel showed uneven distribution of the fuel resulting in parabolic concentration profiles, an indication of insufficient mixing in the reburn zone. In order to study mechanisms of nitrogenous species destruction in the reburn zone, it is necessary to achieve adequate mixing if the assumption of one dimensional plug flow behavior is to be valid. Thus, it became necessary to modify the injector design and the injection mode of the reburn fuel to achieve an adequate level of mixing which is the focus of this report. The results show that a minimum reburn fuel jet velocity of 15 m/s (standard ...

1989-08-25

460

Measurements of single and double spin asymmetry in pp elastic scattering in the CNI region with a polarized atomic hydrogen gas jet target  

International Nuclear Information System (INIS)

Precise measurements of the single spin asymmetry AN, and the double spin asymmetry ANN, in proton-proton (pp) elastic scattering in the region of four-momentum transfer squared 0.0012 have been performed using a polarized atomic hydrogen gas jet target and the Relativistic Heavy Ion Collider (RHIC) polarized proton beam. We present measurements of AN and ANN at center-of-mass energies ?(s)=6.8 and 13.7 GeV. These spin-dependent observables are sensitive to the poorly known hadronic spin-dependent amplitudes. Comparing AN at different energies, a ?(s) dependence of the hadronic single spin-flip amplitude is suggested. A hadronic double spin-flip amplitude from the ANN data is consistent with zero within a 2-? level. We also present ??T, estimated from the measured ANN data. The results for ??T are consistent with zero. Our results provide significant constraints toward a comprehensive understanding of the reaction mechanism for pp elastic scattering.

2009-05-01

461

Indoor air quality and thermal comfort studies of an under-floor air-conditioning system in the tropics  

Energy Technology Data Exchange (ETDEWEB)

This paper reports thermal comfort and indoor air quality (IAQ) studies of an under-floor air-conditioning (UFAC) system in a hot and humid climate. Thermal comfort parameters were measured at pre-determined grid points within an imaginary plane to predict the air flow pattern of the supply air jet as well as to determine the occurrence of thermal stratification in the office space. Fanger's thermal comfort index was also computed to detect the occupants' thermal sensation. Besides, the concentration levels of dust and carbon dioxide were recorded with the intention to examine the quality of the indoor air. Statistical methods were applied to derive the relationship between air velocity and the other parameters as mentioned earlier. The main findings from the study revealed reasonable level of acceptability of IAQ associated with the UFAC system. However, occupants are likely to experience localised thermal discomfort near the supply diffusers due ...

2002-07-01

462

Improved recovery demonstration for Williston Basin carbonates. Quarterly report, January 1, 1995--March 31, 1995  

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Cores from five Red River wells in the Bowman-Harding study area have been examined and described in detail; contracts have been awarded for a 3-D survey in Bowman Co., ND and a 2D, multi-component survey in Richland Co.; extended-time pressure buildup data have been analyzed from two wells which are candidates for jetting-lance completion workovers; a 20-day injectivity test has been completed in the Red River (upper member); a jetting-lance completion program has commenced with one job completed and three more scheduled during April; and reservoir data from three key Red River fields in the Bowman-Harding study area has ...

1995-05-01

463

Impact of the recent results by the CMS and ATLAS Collaborations at the CERN Large Hadron Collider on an effective Minimal Supersymmetric extension of the Standard Model  

CERN Document Server

We discuss the impact for light neutralinos in an effective Minimal Supersymmetric extension of the Standard Model of the recent results presented by the CMS and ATLAS Collaborations at the CERN Large Hadron Collider for a search of supersymmetry in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 35 inverse pb. We find that, in the specific case of light neutralinos, efficiencies for the specific signature searched by ATLAS (jets+missing transverse energy and an isolated lepton) imply a lower sensitivity compared to CMS (which searches for jets +missing transverse energy). Focusing on the CMS bound, if squark soft masses of the three families are assumed to be degenerate, the combination of the ensuing constraint on squark and gluino masses with the experimental limit on the b to s + gamma decay imply a lower bound on the neutralino mass that can reach the value of 11.9 GeV, depending on the gluino ...

2011-01-01

464

High efficiency coupling and guiding of intense femtosecond laser pulses in preformed plasma channels in an elongated gas jet  

International Nuclear Information System (INIS)

We report coupling and guiding of pulses of peak power up to 0.3 TW in 1.5 cm long preformed plasma waveguides generated in a high repetition rate argon gas jet. Coupling of up to 52% was measured for 50 mJ, -110 fs pulses injected at times longer than 20 ns, giving guided intensities up to -5x1016 W/cm2. It was found that for short delays between waveguide generation and pulse injection, pulse shortening occurred, with this effect reduced as delay was increased. Injection into the waveguide of two consecutive pulses separated by a few nanoseconds resulted in the reduction of shortening of the second pulse at all delays. Femtosecond time-resolved shadowgrams of the coupling of injected pulses into the waveguide show that there is ?0.5 mm of neutral gas remaining at the waveguide entrance after waveguide generation.

1999-07-12

465

Foam for combating mine fires  

Energy Technology Data Exchange (ETDEWEB)

The application of foam in dealing with underground fire is well known due to its smothering action by cutting off air feed to burning fuel as well as acting as coolant. Besides plugging air feed to fire, water could be virtually reached to the fire affected areas much beyond the jet range as underground galleries with low roof restrict jet range of water. This method also enables a closer approach of a fire fighting team by isolating the toxic gases and smoke with a foam plug. The paper describes the development of high expansion foam composition and its application technology in order that foam plug method can be suitably utilized for combating mine fires in India. Three compositions were recommended for generation of high expansion foam: (a) 0.5% sodium/ammonium lauryl sulphate, 0.15 to 0.2% sodium carboxy methyl cellulose, 0.1% booster; (b) 0.5% sodium/ammonium lauryl sulfate, 0.12 to 0.15% alkaline solution of gum arabic, 0.1 to 0.2% ...

1989-09-01

466

Effect of heat transfer augmentation by square rod array in impinging air jet system(heat transfer characteristic of potential core region)  

Energy Technology Data Exchange (ETDEWEB)

This research has been proceeded over the potential core region (H/B=2) of two-dimensional impinging air jet system, in which square rods(width of 6 mm) has been set up in front of heating surface in order to increase heat transfer. The objective of this research was to investigate the characteristics of heat transfer and air flow, in cases of the clearance from rods to heating surface (C = 1, 2, 4, 6 mm) and the pitch between each rods(P = 30, 40, 50 mm) changed. And this research compared the above with the experimentation without rods. As result, heat transfer performance was best under the condition of C = 1 mm, in case clearance changed, and there was no serious difference in the effect of heat transfer augmentation in the case of pitch of rods changed. (author) 11 refs. 12 figs.

1995-07-01

467

Effect of chemical composition of SiOx films on rapid formation of Si nanocrystals induced by thermal plasma jet irradiation  

British Library Electronic Table of Contents (United Kingdom)

Si nanocrystal floating gate MOS capacitors were formed on p-Si (100) wafers by thermal plasma jet (TPJ) annealing of SiO2/SiOx /SiO2/Si(100) stacked structure. The chemical composition of SiOx layer was controlled by changing the SiH4, He, and O2 gas flow ratio during plasma enhanced chemical vapour deposition. The MOS capacitors showed clear hysteresis in capacitance-voltage (CV) characteristics after TPJ annealing. The hysteresis width shows maximum value when initial composition x =1.7, which shows the maximum photoluminescence (PL) intensity. The maximum hysteresis width of 6.8 V was observed with gate voltage swept between 20 and -20 V in x = 1.7 sample. The result means 7.4 x 1012 cm-2 carriers are injected to or emitted from Si nanocrystals. The duration of 1 V shift in flatband vo...

2010-01-01

468

Wind loss prevention for open cavity solar receivers  

Energy Technology Data Exchange (ETDEWEB)

Apparatus for minimizing thermal loss in a windowless, open cavity solar receiver due to airflow at the receiver aperture includes means for deflecting wind away from the cavity opening such that flow stream reattachment occurs away from the receiver aperture to provide a dead air zone at the cavity opening. This prevents turbulent-mixing airflow exchange between ambient air and heated air within the solar receiver. The wind deflector apparatus includes either a passive annular deflection foil at the receiver aperture, or an active device for producing an outwardly projected air jet at the receiver aperture.

1982-01-26

469

Study of the state of design for pipe whip. Final report. [PWR; BWR  

Energy Technology Data Exchange (ETDEWEB)

Design methods and parameters are described which are addressed when considering consequences of a postulated pipe rupture event in a nuclear plant design. Parameters discussed are break opening time and size, resultant blowdown characteristics of the effluent from the broken pipe, jet reaction and impingement loading, pipe motion, and pipe impact loading on steel and concrete structures. The impact the various parameters have on overall plant designs and conservatisms inherent in each consideration are evaluated in a qualitative nature. Finally, recommendations are provided for each parameter discussed for further evaluation and study.

1980-01-01

470

Short term energy shortages. Hearings before the subcommittee on energy of the Committee on Science and Astronautics, U.S. House of Representatives, Ninety-Third Congress, First Session, May 3, 8, 17, 1973  

Science.gov (United States)

>The causes and implications of the impeading shortages of gasoline, heating oil, diesel fuel, jet fuel, and electricity were investigated at the May 3, 1973 hearings. Discussions and related data were presented on short-term fuel shortages and their effects on the electric utilfties and the present situation in the regulated energy industries and its effects on energy R&D. The statement of the national oil lobbers council is presented in an appendix. (MCW)

1973-01-01

471

Safety design guide for pipe rupture protection for CANDU 9  

Energy Technology Data Exchange (ETDEWEB)

This safety design guide for pipe rupture protection identifies high-energy systems in which pipe ruptures must be postulated to occur, as well as systems that must be protected from the dynamic effects of such ruptures. Dynamic effects considered in this SDG consist of pipe whip (including missiles generated by pipe ruptures, if any) and jet impingement, Requirements for protection against the dynamic effects of a postulated pipe rupture and method of protection of essential structures, systems and components are specified for these effects. The change status for the regulatory requirements, code and standards should be traced and this safety design guide shall be updated accordingly. 2 tabs., 5 refs. (Author) .new.

1996-03-01

472

SKA in VLBI Impact on Studies of Small Scale Structures in Active Galactic Nuclei  

CERN Document Server

We discuss the advantages which the next generation interferometer SKA (the Square Kilometer Array) will bring for Very Long Baseline Interferometry (VLBI) at centimeter wavelengths. With a sensitivity to micro-Jy level flux density, a brightness temperature limit of about 10.000 K, and an expected dynamic range in future VLBI maps of better than 1.000.000, the impact of SKA on the research of compact extragalactic radio sources and their energetic jets will be very strong. We discuss some consequences, including a possible combination of SKA with future space VLBI missions.

1999-01-01

473

Replace the Carburetor Diaphragm. Pulsa-Jet Style with Automatic Choke. Fuel System. Student Manual 2. Small Engine Repair Series. First Edition.  

Science.gov (United States)

This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. The manual explains in pictures and short sentences, written on a low reading level, the job of replacing carburetor diaphragms. Along with the steps of this repair job, specific safety and caution information is frequently noted. To reinforce consistency in material presented to the slow learners, the pictures and written words correspond exactly with the pictures and wording on a corresponding audiovisual presentation. A progress chart for rating the students is included in the manual. (KC)

1981-12-01

474

Negative snakes in JET: evidence for negative shear  

Energy Technology Data Exchange (ETDEWEB)

The signature of the negative snakes from the soft X-ray cameras is very similar to the more usual snakes except that the localised region of the snake has, compared with its surroundings, decreased rather than increased emission. Circumstances where negative snakes have been seen are reviewed. The negative snake appears as a region of increased resistance and of increased impurity density. The relationship between the shear and the current perturbation is shown, and it seem probable that the magnetic shear is reversed at the point of the negative snake, i.e. that q is decreasing with radius. 6 refs., 6 figs.

1994-07-01

475

Near-threshold production of {omega}-mesons in the pn{yields}d{omega} reaction  

Energy Technology Data Exchange (ETDEWEB)

The first measurement of the pn{yields}d{omega} total cross-section has been achieved at mean excess energies Q{approx}28 and 57 MeV by using a deuterium cluster-jet target. The momentum of the fast deuteron was measured in the ANKE spectrometer at COSY-Juelich and that of the slow ''spectator'' proton (p{sub sp}) from the pd{yields}p{sub sp}d{omega} reaction in a silicon telescope placed close to the target. The cross-sections lie above those measured for pp{yields}pp{omega} but seem to be below theoretical predictions. (orig.)

2004-09-01

476

Forward Physics with the CMS experiment at the Large Hadron Collider  

CERN Document Server

multi-parton interactions and underlying event structure, $\\gamma$-mediated processes and luminosity determination, Monte Carlo tuning and even MSSM Higgs discovery in central exclusive production. In this article, the forward detector instrumentation around the CMS interaction point is described and the prospects for diffractive and forward physics using the CMS forward detectors are summarized. In addition, first observation of forward jets as well as early measurements of the forward energy flow in the pseudorapidity range $3.15

2010-01-01

477

Electron collisional detachment processes for a 250 keV D/sup -/ ion beam in a partially ionized hydrogen target  

Energy Technology Data Exchange (ETDEWEB)

Neutral atom beams with energies above 200 keV may be required for various purposes in magnetic fusion devices following TFTR, JET and MFTF-B. These beams can be produced much more efficiently by electron detachment from negative ion beams than by electron capture by positive ions. We have investigated the efficiency with which such neutral atoms can be produced by electron detachment in partially ionized hydrogen plasma neutralizers.

1980-09-01

478

Development of thin foil Faraday collector as a lost alpha particle diagnostic for high yield D-T tokamak fusion plasmas  

Energy Technology Data Exchange (ETDEWEB)

Alpha particle confinement is necessary for ignition of a D-T tokamak fusion plasma and for first wall protection. Due to high radiation backgrounds and temperatures, scintillators and semiconductor detectors may not be used to study alpha particles which are lost to the first wall during the D-T programs on JET and ITER. An alternative method of charged particle spectrometry capable of operation in these harsh environments, is proposed: it consists of thin foils of electrically isolated conductors with the flux of alpha particles determined by the positive current flowing from the foils. 2 refs., 3 figs.

1994-07-01

479

Decaying into the Hidden Sector  

CERN Document Server

The existence of light hidden sectors is an exciting possibility that may be tested in the near future. If DM is allowed to decay into such a hidden sector through GUT suppressed operators, it can accommodate the recent cosmic ray observations without over-producing antiprotons or interfering with the attractive features of the thermal WIMP. Models of this kind are simple to construct, generic and evade all astrophysical bounds. We provide tools for constructing such models and present several distinct examples. The light hidden spectrum and DM couplings can be probed in the near future, by measuring astrophysical photon and neutrino fluxes. These indirect signatures are complimentary to the direct production signals, such as lepton jets, predicted by these models.

2009-01-01

480

Analysis of JET LCHD/ICRH synergy experiments in terms of relativistic current drive theory  

Energy Technology Data Exchange (ETDEWEB)

The present analysis shows that the observed efficiency of current drive with synergy between LHCD and ICRH is in good agreement with the relativistic theory of Karney and Fisch for Landau damped waves. The predicted power absorption from the fast wave by the electron tail is within 30% of the measured value. In the presence of significant fast electron diffusion within a slowing down time it would be possible to produce central current drive using multiple ICRF resonances even when the LHCD deposition is at half radius, as in an ITER type device. (authors). 4 refs., 6 figs.

1994-07-01

481

Tunable far infrared laser spectroscopy of Van der Waals molecules in a planar supersonic jet expansion  

Energy Technology Data Exchange (ETDEWEB)

The gas phase high resolution spectroscopic study of weakly bound clusters can provide the information necessary to develop an intermolecular potential energy surface. This surface can then be used to better understand condensed phases. In this work, a tunable far infrared laser spectrometer is used to study weakly bound dimers produced in the newly developed continuous planar supersonic jet expansion apparatus. The water dimer is an extensively studied hydrogen bonded dimer. It undergoes several tunneling motions which result in splittings and perturbations of the rovibrational energy levels. A review is presented of much of the experimental and theoretical work done on water dimer, including a description of the combined fit of all the high resolution spectroscopic results by Coudert and Hougen. Also included is a discussion of the measurement of the K = 1 lower {yields} K = 2 lower band performed using the tunable far infrared laser/planar ...

1990-12-01

482

Mechanisms of heat transfer augmentatiton around the stagnation point of an impinging air jet laden with solid particles. Report 2. ; Effects of thermal properties of laden particles and heat transfer surface on heat transfer augmentation due to the unsteady heat conduction. Koki niso shototsu funryu no yodomiten kinbo ni okeru dennetsu sokushin kiko. 2. ; Sesshoku netsudendo ni yoru dennetsu sokushin ni taisuru ryushi to dennetsumen no netsubusseichi no eikyo to sono hyoka  

Energy Technology Data Exchange (ETDEWEB)

The heat transfer augmentation effect by the unsteady heat conduction between the particles and heat transfer surface is one of the main factors, causing the heat transfer augmentation around the stagnation point in the gas-solid two-phase impinging jet flow. By separating and evaluating that effect, material influence on it was studied of particles and heat transfer surface, together with change by the jet flow condition. That effect enlarged with enlarging in heat capacity, multiplied by the heat conduction coefficient, of both the particles and heat transfer surface, and if both of them were constant in material combination, was dominated by the contact frequency of particles per unit time. Therefore in case of lading solid particles, equal in weight, that effect enlarges with diminishing in particle diameter. Such a heat transfer augmentation mechanism model is universally applicable to the data by Yoshida et al., using comparatively large ...

1991-05-25

483

Mechanisms of heat transfer augmentaiton around the stagnation point of an impinging air jet laden with solid particles. Report 1. ; Evaluation procedure of heat transfer augmentaion due to unsteady heat conduction between laden particles and heat transfer surface. Koki niso shototsu funryu no yodomiten kinbo ni okeru dennetsu sokushin kiko. 1. ; Ryushi eno chokusetsu sesshoku netsuido ni yoru dennetsu sokushin koka no bunri hoho  

Energy Technology Data Exchange (ETDEWEB)

Several heat transfer augmentation mechanisms contribute to the heat transfer augmentation around the stagnation point in the gas-solid two-phase impinging jet flow. Among those contributions, that of heat exchange was numerically analyzed and characteristically elucidated by the unsteady direct contact heat conduction at the time of impingement between the laden particles and heat transfer surface. In other words, if the contact time is short between the particles and heat transfer surface, the former is heated by heat stored in the latter as a heat capacity. In such a region, the heat quantity to be transferred to the particles changes by not only the thermal property value (heat capacity multiplied by heat conduction coefficient) of particles but also that of heat transfer surface. Then by using several kinds of particles and heat transfer surface, different in thermal property value, experimental measurement was planned of heat transfer augmentations, different ...

1991-05-25

484

Fragmentation of a single molten metal droplet penetrating sodium pool I copper droplet and the relationship with copper jet  

International Nuclear Information System (INIS)

The progression of hypothetical core disruptive accidents in metallic fuel fast breeder reactors is strongly affected by the fragmentation of molten metallic fuels due to the molten fuel-coolant interaction (FCI). As a basic study of FCI, the present paper focuses on the fragmentation of a single molten copper droplet with mass from 1 to 5 g, which penetrated a sodium pool at instantaneous constant interface temperatures (Ti) from 995 to 1,342degC. Intensive fragmentation of a single molten copper droplet was clearly observed even if Ti values are below the melting point (1,083degC) of copper besides the higher Ti range. The intensive fragmentation shows that the mass median diameters (Dm) of copper droplets with a fivefold difference in mass or the same mass have little difference, i.e., they are nearly the same. Under the lower Ti condition, the Dm data of droplet fragments of both the same and different masses scatter widely. It is found that the present Dm/D0 data of mass median ...

2009-05-01

485

ELM resolved energy distribution studies in the JET MKII Gas-Box divertor using infra-red thermography  

International Nuclear Information System (INIS)

Using infra-red (IR) thermography, power loads onto the MKII Gas-Box divertor targets have been investigated in Type-I ELMy H-Mode plasmas at JET in medium current discharges (Ip = 2.6 MA and BT = 2.7 T). Heat fluxes are calculated from the measured divertor target tile surface temperatures taking into account the influence of co-deposited surface layers on tile surfaces. This is particularly important when estimating the energy deposition during transient events such as ELMs. Detailed energy balance analysis is used, both from IR and tile embedded thermocouples, to demonstrate an approximately constant ELM-averaged in/out divertor target asymmetry of ?0.55 and to show that the ELM in/out energy deposition ratio ranges from 1 : 1 to 2 : 1. The inter-ELM in/out ratio is close to the ELM-averaged value at low pedestal collisionalities and decreases down to values close to zero when the inner target plasma detaches at the highest pedestal collisionalities. The ...

2007-05-01

486

Imaging of offset VSP data with an elastic iterative migration scheme  

Energy Technology Data Exchange (ETDEWEB)

VSP data are usually acquired in order to obtain high-resolution images of complex structures in reservoirs and near boreholes. The authors present an elastic iterative migration scheme which has few limitations regarding the complexity of the geology, and where the macromodel for both P- and S-wave velocities is automatically improved and updated at each iteration. They avoid wavefield separation (up/down and P/S) and the simplifying assumptions of small dips underlying most such methods. The migration scheme is based on elastic inversion theory. The wavefield extrapolation is based on a high-order, coarse-grid, finite-difference solution to the elastic two-way wave equation. At each iteration, the macromodel is updated using a gradient method, in which the gradient is computed by correlation of forward-modelled fields with back-propagated residual fields. The first iteration of the migration scheme is equivalent to ...

1997-03-01

487

Development and application of a third order scheme of finite differences centered in mesh; Desarrollo y aplicacion de un esquema de tercer orden de diferencias finitas centradas en malla  

Energy Technology Data Exchange (ETDEWEB)

In this work the development of a third order scheme of finite differences centered in mesh is presented and it is applied in the numerical solution of those diffusion equations in multi groups in stationary state and X Y geometry. Originally this scheme was developed by Hennart and del Valle for the monoenergetic diffusion equation with a well-known source and they show that the one scheme is of third order when comparing the numerical solution with the analytical solution of a model problem using several mesh refinements and boundary conditions. The scheme by them developed it also introduces the application of numeric quadratures to evaluate the rigidity matrices and of mass that its appear when making use of the finite elements method of Galerkin. One of the used quadratures is the open quadrature of 4 points, no-standard, of Newton-Cotes to evaluate in approximate form the elements of the rigidity ...

2003-07-01

488

Closure relations for the multi-species Euler system. Construction and study of relaxation schemes for the multi-species and multi-components Euler systems; Relations de fermeture pour le systeme des equations d'Euler multi-especes. Construction et etude de schemas de relaxation en multi-especes et en multi-constituants  

Energy Technology Data Exchange (ETDEWEB)

After having recalled the formal convergence of the semi-classical multi-species Boltzmann equations toward the multi-species Euler system (i.e. mixture of gases having the same velocity), we generalize to this system the closure relations proposed by B. Despres and by F. Lagoutiere for the multi-components Euler system (i.e. mixture of non miscible fluids having the same velocity). Then, we extend the energy relaxation schemes proposed by F. Coquel and by B. Perthame for the numerical resolution of the mono-species Euler system to the multi-species isothermal Euler system and to the multi-components isobar-isothermal Euler system. This allows to obtain a class of entropic schemes under a CFL criteria. In the multi-components case, this class of entropic schemes is perhaps a way for the treatment of interface problems and, then, for the treatment of the numerical mixture area by using a Lagrange + projection ...

2001-07-01

489

Structures and properties of fluorinated amorphous carbon films  

International Nuclear Information System (INIS)

Fluorinated amorphous carbon (a-C:F) films were deposited by radio frequency bias assisted microwave plasma electron cyclotron resonance chemical vapor deposition with tetrafluoromethane (CF_4) and acetylene (C_2H_2) as precursors. The deposition process was performed at two flow ratios R=0.90 and R=0.97, where R=CF_4/(CF_4+C_2H_2). The samples were annealed at 300 deg. C for 30 min. in a N_2 atmosphere. Both Fourier transform infrared and electron spectroscopy for chemical analyzer were used to characterize the a-C:F film chemical bond and fluorine concentration, respectively. A high resolution electron energy loss spectrometer was applied to detect the electronic structure. The higher CF_4 flow ratio (R=0.97) produced more sp"3 linear structure, and it made the a-C:F film smoother and softer. A lifetime of around 0.34 #mu#s and an energy gap of #approx#2.75 eV were observed in both the as-deposited and after annealing conditions. The short ...

2004-07-01

490

Properties of dust particles sampled from windboxes of an iron ore sintering plant: Surface structures of unburned carbon  

Energy Technology Data Exchange (ETDEWEB)

Aiming to understand the formation mechanism of dioxins in the iron ore sintering process, dust samples obtained from some windboxes of a commercial iron ore sintering plant have been characterized with a powder X-ray diffraction (XRD), by the transmission electron microscope (TEM) equipped with an electron energy loss spectroscopy (EELS), and by the temperature-programmed desorption (TPD) and temperature-programmed oxidation (TPO) techniques. The elemental and XRD analyses reveal that the content of the Cl present in the samples ranges from 0.075 mass%-dry to 5.1 mass%-dry and tends to be higher at smaller dust particles, and that some of the Cl exists as KCl with the average crystalline size between 40 nm and 50 nm. Dust samples also contain a significant amount of unburned carbon, and the smallest dust particles, < 500 {mu}m, show the highest C contents in many cases and consist partly of C, K, and Cl elements. The TPD and TPO ...

2006-07-01

491

M-shell x-ray production by 0.6--4.0-MeV protons in ten elements from hafnium to thorium  

International Nuclear Information System (INIS)

M-shell x-ray production cross sections for selected heavy elements, namely, _7_2Hf, _7_3Ta, _7_4W, _7_5Re, _7_6Os, _7_7Ir, _7_8Pt, _7_9Au, _8_3Bi, and _9_0Th, were measured for protons of energy 0.6--4.0 MeV. The experimental results are compared with the predictions of the first Born and semiclassical approximations for M-shell ionization; these data are also compared with the theory that accounts for the projectile's energy loss and Coulomb deflection as well as for the target's M-shell electron perturbed stationary state and relativistic nature (ECPSSR). Generally, fair agreement between the data and the ECPSSR theory is found. Some systematical discrepancies observed for the lightest elements (Hf, Ta, and W) are explained as possible ambiguities in the M-shell Coster-Kronig factors and fluorescence yields, which were used to convert theoretical M-subshell ionization cross sections to the total M-x-ray production cross sections. The ...

492

Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical study  

Energy Technology Data Exchange (ETDEWEB)

High voltage cathode materials Li-excess layered oxide compounds Li[Ni{sub x}Li{sub 1/3-2x/3}Mn{sub 2/3-x/3}]O{sub 2} (0 < x < 1/2) are investigated in a joint study combining both computational and experimental methods. The bulk and surface structures of pristine and cycled samples of Li[Ni{sub 1/5}Li{sub 1/5}Mn{sub 3/5}]O{sub 2} are characterized by synchrotron X-Ray diffraction together with aberration corrected Scanning Transmission Electron Microscopy (a-S/TEM). Electron Energy Loss Spectroscopy (EELS) is carried out to investigate the surface changes of the samples before/after electrochemical cycling. Combining first principles computational investigation with our experimental observations, a detailed lithium de-intercalation mechanism is proposed for this family of Li-excess layered oxides. The most striking characteristics in these high voltage high energy density cathode materials are (1) formation of tetrahedral lithium ...

2011-09-06

493

Heavy ion induced changes in nuclear waste glasses: a micro Raman investigation  

International Nuclear Information System (INIS)

Borosilicate based glass formulations have been found suitable for fixing the HLW (high level radioactive liquid waste) generated after reprocessing of the spent nuclear fuel. As the glass experiences continuous irradiation by #alpha#, #beta#a, and #gamma# radiations from the radioactive components of HLW, alteration in the glass structure may occur. Understanding of these structural evolutions of the nuclear waste glasses under irradiation is crucial to secure long term disposal and predict their behavior. In the present work, alkali based barium borosilicate glasses, having composition similar to that of Trombay Research Reactor waste glass were irradiated with high energy "1"2C beam and the radiation induced changes were monitored by micro Raman experiment. Since a "1"2C atom can be considered as a cluster of alphas, this beam was chosen to yield linear energy losses (LET) comparable to that in case of a particles. The irradiations were ...

2010-12-01

494

Electrochemical reduction of graphited materials in LiClO{sub 4}-EC and LiClO{sub 4}-PC media: characterization of interface products by transmission electron microscopy; Reduction electrochimique de materiaux graphites en milieux LiCIO{sub 4}-EC et LiCIO{sub 4}-PC: caracterisation des produits d`interface par microscopie electronique a transmission  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical intercalation of non-solvated lithium in different graphited materials has been performed in LiClO{sub 4}-ethylene carbonate (EC) medium. The irreversible capacity observed during the first output is mainly due to the formation of a passivation layer made of electrolyte reduction products. These products have been characterized for different electrode reduction potentials using transmission electron microscopy (image, diffraction) and electron energy loss spectroscopy (EELS). EC reduction on the electrode surface in presence of LiClO{sub 4} leads to the formation of Li{sub 2}CO{sub 3} for potentials close to 0.8 V vs Li{sup +}/Li. For lower potentials, the electrolyte reduction reaction goes on with the formation of different lithium alkyl-carbonates. In LiClO{sub 4}-propylene carbonate (PC) medium, the interface phenomena are different. The reduction of a graphite electrode is characterized by the exfoliation phenomenon ...

1996-12-31

495

Effect of nitrogen segregation on TED and loss of phosphorus in CZ-Si  

Energy Technology Data Exchange (ETDEWEB)

Transient enhanced diffusion (TED) and dose loss (pile-up) are investigated for phosphorus-implanted samples covered with both oxide and nitride films. P ions were implanted into p-type (1 0 0) CZ-Si (dose 5x10{sup 13} cm{sup -3}, 100 keV) through a chemical vapor deposition (CVD) Si{sub 3}N{sub 4} film. For a half of samples, Si{sub 3}N{sub 4} was etched off and SiO{sub 2} films were grown by CVD. Both samples were annealed for 20-360 min at 700 deg. C. Diffusivity of P and the dose loss were estimated based on the secondary-ion mass spectrometry (SIMS) P profiles. Both Si/Si{sub 3}N{sub 4} and Si/SiO{sub 2} interfaces were investigated with transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS). There is no significant difference in P diffusivity between the SiO{sub 2} and Si{sub 3}N{sub 4} films for the present annealing condition of 700 deg. C for 20-360 min. Regarding dose loss, a distinct different behavior was observed. In case ...

2002-01-01

496

Effect of nitrogen segregation on TED and loss of phosphorus in CZ-Si  

International Nuclear Information System (INIS)

Transient enhanced diffusion (TED) and dose loss (pile-up) are investigated for phosphorus-implanted samples covered with both oxide and nitride films. P ions were implanted into p-type (1 0 0) CZ-Si (dose 5x10"1"3 cm"-"3, 100 keV) through a chemical vapor deposition (CVD) Si_3N_4 film. For a half of samples, Si_3N_4 was etched off and SiO_2 films were grown by CVD. Both samples were annealed for 20-360 min at 700 deg. C. Diffusivity of P and the dose loss were estimated based on the secondary-ion mass spectrometry (SIMS) P profiles. Both Si/Si_3N_4 and Si/SiO_2 interfaces were investigated with transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS). There is no significant difference in P diffusivity between the SiO_2 and Si_3N_4 films for the present annealing condition of 700 deg. C for 20-360 min. Regarding dose loss, a distinct different behavior was observed. In case of the SiO_2 cover film, amount of dose decreases with the ...

2002-01-01

497

Dynamical Cycles in Charge and Energy for Iron Ions Accelerated in a Hot Plasma  

Science.gov (United States)

We consider a unified model of Fe ion acceleration in the solar corona. The model comprises charge-changing processes, Coulomb energy losses, and both regular and stochastic acceleration. At a given acceleration scenario, the type of acceleration is found to have a minor effect on the mean charge states, but the shapes of the charge-state distributions produced by regular acceleration and by stochastic acceleration are different. During a continual acceleration at coronal temperatures, iron ions typically follow rising trajectories on the charge-energy plane. These trajectories are situated below the mean equilibrium charge curve defined from the balance of ionization and recombination at fixed energy. During stopping, the iron ions cross the equilibrium charge curve and run through a series of charge states above the mean equilibrium charge at current energy, because the Coulomb deceleration rate significantly exceeds the rate of the ion ...

2001-08-01

498

Analysis of degradation in nickel-based alloys using focused ion beam imaging and specimen preparation combined with analytical electron microscopy  

International Nuclear Information System (INIS)

Focused ion beam (FIB) microscopes have become well-established in the semiconductor industry during the past decade, and are rapidly gaining attention in the field of materials science, both as a tool for producing site specific, parallel sided transmission electron microscope (TEM) specimens and as stand alone specimen preparation and imaging systems. FIB secondary electron imaging (SEI) of nickel-based alloys, such as commercially produced Alloy 600 (approximately Ni 15Cr 10Fe 0.5C), has been demonstrated to show a high degree of sensitivity to the presence of deformation in the alloy, and FIB secondary ion imaging (SII) is particularly useful for identifying the presence of grain boundary corrosion, as secondary ion yields from metallic specimens can increase by three orders of magnitude in the presence of oxygen. This 'oxygen enhanced yield', makes FIB SII ideal for detection of corrosion at grain boundaries down to thicknesses of only a few tens of nanometers. Historically, while ...

2002-09-23

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Analysis of cost-effective pipe insulation requirements  

Energy Technology Data Exchange (ETDEWEB)

The proposed ASHRAE/IES Standard 90.1-1989R contains updated requirements for pipe insulation thicknesses developed on the basis of technical and economic principles. These requirements were determined based on computer simulations of the annual energy loss through the insulation, first cost assumptions for the insulation, and economic assumptions of discount rate and energy escalation rate. In later work, the same tools were used to analyze the sensitivity of the cost-effective insulation level for piping insulation to variations in operating hours, ambient temperature, fluid temperature, and economic assumptions. These analyses were carried out using cost data for pipe insulation averaged across several sources. The results of the sensitivity study showed that system operating hours is a critical parameter in determining the cost-effective pipe insulation thicknesses. Although there is a lack of reliable sources of typical operating hour data ...

1997-09-01