WorldWideScience
1

Two years of flight of the Pamela experiment: results and perspectives  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antinuclei with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, $15^{th}$ 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. In this work we describe the scientific objectives and the performance of PAMELA in its first two years of operation. Data on protons of trapped, secondary and galactic nature - as well as measurements of the December $13^{th}$ 2006 Solar Particle Event - are also provided.

2008-01-01

2

PAMELA results on the cosmic-ray antiproton flux from 60 MeV to 180 GeV in kinetic energy  

CERN Document Server

The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in kinetic energy. During 850 days of data acquisition approximately 1500 antiprotons were observed. The measurements are consistent with purely secondary production of antiprotons in the galaxy. More precise secondary production models are required for a complete interpretation of the results.

2010-01-01

3

A new measurement of the antiproton-to-proton flux ratio up to 100 GeV in the cosmic radiation  

CERN Document Server

A new measurement of the cosmic ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. PAMELA is equipped with a silicon-microstrip magnetic spectrometer and a silicon-tungsten imaging calorimeter and has been collecting data since July 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a ten-fold improvement in statistics with respect to all previously published data. The antiproton-to-proton flux ratio increases smoothly with energy up to about 10 GeV, in agreement with previous experiments, and then levels off. The data follow the trend expected from secondary production calculations ...

2008-01-01

4

The Pamela Cosmic Ray Space Observatory: Detector, Objectives and First Results  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers ...

2009-01-01

5

Positrons and antiprotons from inert doublet model dark matter  

CERN Document Server

We investigate the signatures of antimatter in cosmic rays that would result from annihilations of the scalar dark matter candidate of the Inert Doublet Model. We consider three benchmark candidates, all consistent with the WMAP cosmic abundance and existing direct detection experiments, and confront the predictions of the model with the recent PAMELA, ATIC and HESS data. For a light IDM WIMP candidate, M_{DM} = 10 GeV, we argue that the positron and antiproton fluxes are large, but consistent with expected backgrounds, unless there is an enhancement in the local density of dark matter. For an IDM WIMP candidate with M_{DM} = 70 GeV, the contribution is lower than the expected backgrounds unless there is a large boost factor. However, the candidate is enable to explain the excesses observed by the recent experiments. Finally, for an IDM WIMP candidate with M_{DM}=10 TeV, it is possible to fit the ...

2009-01-01

6

Capability of the PAMELA Time-Of-Flight to identify light nuclei: results from a beam test calibration  

CERN Document Server

PAMELA is a space telescope orbiting around the Earth since June 2006. The scientific objectives addressed by the mission are the measurement of the antiprotons and positrons spectra in cosmic rays, the hunt for anti-nuclei as well as the determination of light nuclei fluxes from Hydrogen to Oxygen in a wide energy range and with very high statistics. In this paper the charge discrimination capabilities of the PAMELA Time-Of-Flight system for light nuclei, determined during a beam test calibration, will be presented.

2008-01-01

7

The PAMELA space experiment: first year of operation  

Energy Technology Data Exchange (ETDEWEB)

On the 15th of June 2006 the PAMELA experiment, mounted on the Resurs DK1 satellite, was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. PAMELA is a satellite-borne apparatus designed to study charged particles in the cosmic radiation, to investigate the nature of dark matter, measuring the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved, and to search for antinuclei with unprecedented sensitivity. The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows charged particle identification over a wide energy range.

2008-05-15

8

PAMELA data and leptonically decaying dark matter  

CERN Document Server

Recently PAMELA released their first results on the positron and antiproton ratios. Stimulated by the new data, we studied the cosmic ray propagation models and calculated the secondary positron and antiproton spectra. The low energy positron ratio can be consistent with data in the convection propagation model. Above $\\sim 10$ GeV PAMELA data shows a clear excess on the positron ratio. However, the secondary antiproton is roughly consistent with data. The positron excess may be a direct evidence of dark matter annihilation or decay. We compare the positron and anti-proton spectra with data by assuming dark matter annihilates or decays into different final states. The PAMELA data actually excludes quark pairs being the main final states, disfavors gauge boson final states. Only in the case of leptonic final states the positron and anti-proton spectra can be explained simultaneously. We also compare the ...

2008-01-01

9

The study of antiprotons and positrons in cosmic rays with the PAMELA spectrometer  

CERN Document Server

The study of antiprotons and positrons in cosmic rays with the PAMELA spectrometer

1998-01-01

10

A combined interpretation of cosmic ray and antiproton high energy measurements  

Energy Technology Data Exchange (ETDEWEB)

In the last months several ballon and satellite experiments improved significantly our knowledge of cosmic ray (CR) spectra at high energy. In particular CREAM allowed to measure B/C, C/O and N/O ratios up to 1 TeV/n and PAMELA the anti p/p ratio up to 100 GeV with unprecedented accuracy. These measurements offer a valuable probe of CR propagation properties. We performed a statistical analysis to test the compatibility of these results, as well as other most significant experimental data, with the predictions of a new numerical CR diffusion package (DRAGON). We found that above 1 GeV/n all data are consistent with a plain diffusion scenario and point to well defined ranges for the normalization and energy dependence of the diffusion coefficient. (orig.)

2009-09-15

11

The magnetic spectrometer PAMELA for the study of cosmic antimatter in space  

Energy Technology Data Exchange (ETDEWEB)

In the framework of the RIM (Russian Italian mission) program, PAMELA is the experiment devoted to the accurate measurement of the positron and antiproton spectra from the very low energy thresh-old of 100 MeV up to more than 50 GeV, and to hunt antinuclei with sensitivity better than 10{sup -7} in the helium/helium ratio. A permanent magnet equipped by microstrip silicon sensors, measures the particle momentum with MDR=400 GV/c on GF=25 cm{sup 2} sr. An accurate ToF system, a 19 X{sub o} deep imaging calorimeter, an aerogel Cherenkov counter and a TRD detector complement the spectrometer in order an efficient e{sup +-}/p{sup +-} separation and some light isotope identification capability. The PAMELA experiment will be carried out on a 700 km high polar orbit, on board of the Earth-observation meteor-3A satellite, to be launched at the end of 1988.

1995-09-01

12

Full Calculation of Clumpiness Boost factors for Antimatter Cosmic Rays in the light of \\LambdaCDM N-body simulation results  

CERN Document Server

Anti-proton and positron Galactic cosmic ray (GCR) spectra are among the key targets for indirect detection of dark matter (DM). The boost factors, corresponding to an enhancement of the signal|linked to the clumpiness properties of the dark matter distribution|, have been taken as high as thousands in the past. The dramatic impact of these boost factors for indirect detection of antiparticles, for instance with the PAMELA satellite or the coming AMS-02 experiment, asks for their detailed calculation. We take into account the state-of-the-art results of high resolution N-body dark matter simulations to calculate the most likely energy dependent boost factors|linked to the GCR propagation properties|, for anti-protons and positrons. The results from extreme, but still possible, configurations of the clumpy dark matter component is also discussed. Starting from the mass and space distributions of ...

2007-01-01

13

Launch of the Space experiment PAMELA  

CERN Document Server

PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of 10^-8). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15, 2006 in a 350*600 km orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the ...

2007-01-01

14

Pulsars as the Sources of High Energy Cosmic Ray Positrons  

CERN Document Server

Recent preliminary results from the PAMELA satellite indicate the presence of a large flux of positrons (relative to electrons) in the cosmic ray spectrum between approximately 10 and 50 GeV. As annihilating dark matter particles in many models are predicted to contribute to the cosmic ray positron spectrum in this energy range, a great deal of interest has resulted from this observation. Here, we consider pulsars (rapidly spinning, magnetized neutron stars) as an alternative source of this signal. After calculating the contribution to the cosmic ray positron and electron spectra from pulsars, we find that the spectrum observed by PAMELA could plausibly originate from such sources. In particular, a significant contribution is expected from the sum of all mature pulsars throughout the Milky Way, as well as from the most nearby mature pulsars (such as Geminga and B0656+14). The signal from nearby pulsars ...

2009-01-01

15

On the Dark Matter Solutions to the Cosmic Ray Lepton Puzzle  

CERN Document Server

Recent measurements of cosmic ray leptons by PAMELA, ATIC, HESS and Fermi revealed interesting excesses. Many authors suggested particle Dark Matter (DM) annihilations could be at the origin of these effects. In this paper, we critically assess this interpretation by reviewing some results questioning the naturalness and robustness of such an interpretation. Natural values for the DM particle parameters lead to a poor leptons production so that models often require signal enhancement effects that we constrain here. Considering DM annihilations are likely to produce antiprotons as well, we use the PAMELA antiproton to proton ratio measurements to constrain a possible exotic contribution. We also consider the possibility of an enhancement due to a nearby clump of DM. This scenario appears unlikely when compared to the state-of-the-art cosmological N-body simulations. We conclude that the bulk of the observed signals most ...

2009-01-01

16

The PAMELA space mission  

Energy Technology Data Exchange (ETDEWEB)

The PAMELA (a Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics) space mission has been launched on-board the Resurs-DK1 satellite on June 15{sup th} 2006 from the Baikonur cosmodrome, in Kazakhstan. PAMELA is a particle spectrometer designed to study charged particles in the cosmic radiation with special focus on the investigation of the nature of dark matter, by mean of the measure of the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved.

2009-03-15

17

Antideuterons from Dark Matter Decay  

CERN Document Server

Recent observations of a large excess of cosmic-ray positrons at high energies have raised a lot of interest in leptonic decay modes of dark matter particles. Nevertheless, dark matter particles in the Milky Way halo could also decay hadronically, producing not only a flux of antiprotons but also a flux of antideuterons. We show that for certain choices of parameters the antideuteron flux from dark matter decay can be much larger than the purely secondary flux from spallation of cosmic rays on the interstellar medium, while the total antiproton flux remains consistent with present observations. We show that if the dark matter particle is sufficiently light, the antideuteron flux from dark matter decay could even be within the reach of planned experiments such as AMS-02 or GAPS. Furthermore, we discuss the prospects to observe the antideuteron flux in the near future if the steep rise in the positron fraction reported by the PAMELA collaboration ...

2009-01-01

18

Indirect Dark Matter Signals from EGRET and PAMELA compared  

CERN Document Server

Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. The excess of diffuse Galactic Gamma Rays from EGRET shows all the features expected from DMA. The new precise measurements of the antiproton and positron fractions from PAMELA are compared with the EGRET excess. It is shown that the charged particles are strongly dependent on the propagation model used. The usual propagation models with isotropic propagation models are incompatible with the recently observed convection in our Galaxy. Convection leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space. It is shown that such anisotropic propagation models including convection prefer a contribution from DMA for the antiprotons, but the rise in the positron fraction, ...

2009-01-01

19

Constraints on WIMP Dark Matter from the High Energy PAMELA $\\bar{p}/p$ data  

CERN Document Server

A new calculation of the $\\bar{p}/p$ ratio in cosmic rays is compared to the recent PAMELA data. The good match up to 100 GeV allows to set constraints on exotic contributions from thermal WIMP dark matter candidates. We derive stringent limits on possible enhancements of the WIMP \\pbar flux: a $m_{\\rm WIMP}$=100 GeV (1 TeV) signal cannot be increased by more than a factor 6 (40) without overrunning PAMELA data. Annihilation through the $W^+W^-$ channel is also inspected and cross-checked with $e^+/(e^-+e^+)$ data. This scenario is strongly disfavored as it fails to simultaneously reproduce positron and antiproton measurements.

2008-01-01

20

High-energy Cosmic-Ray Positrons from Hidden-Gauge-Boson Dark Matter  

CERN Document Server

We provide a scenario in which a hidden U(1) gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an $U(1)_{B-L}$ gauge boson. Interestingly, our model can naturally account for the steep rise in the positron fraction recently reported by PAMELA. Moreover, we find that due to the charge assignment of $U(1)_{B-L}$, only a small amount of antiprotons are produced in the decay, which is also consistent with the PAMELA and other observational data.

2008-01-01

21

Indirect Dark Matter Signals  

CERN Document Server

Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. Several signatures, ranging from the positron excess, as observed by HEAT, AMS-01 and PAMELA, the gamma ray excess, as observed by the EGRET spectrometer, the WMAP-haze, and constraints from antiprotons, as observed by CAPRICE, BESS and PAMELA, have been discussed in the literature. Unfortunately, the different signatures all lead to different WIMP masses, indicating that at least some of these interpretations are likely to be incorrect. Here we review them and discuss their relative merits and uncertainties. New x-ray data from ROSAT suggests non-negligible convection in our Galaxy, which leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer ...

2008-01-01

22

Vitrification inches towards a solution  

International Nuclear Information System (INIS)

A review is presented of the work being carried out around the world on the vitrification of high-level waste. A description is given of the French AVM process, West Germany's research on the Vera, Fips and Pamela processes and the United Kingdom Harvest process. Mention is also made of the Lotes process being developed by Belguim, and of the inactive vitrification plant in Italy, Ivet 1. (U.K.).

24

Revised neutron dosimetry results for the MOTA-2A experiment in FFTF  

Energy Technology Data Exchange (ETDEWEB)

Revised neutron fluence and damage values are reported for the MOTA-2A experiment in the Fast Flux Test Facility (FFTF). This revision corrects an error with processing of the {sup 235}U(n,f) reaction. Net corrections are on the order of 5%.

1994-09-01

25

DEMONSTRATION/EVALUATION OF THE CAT-OX FLUE GAS DESULFURIZATION SYSTEM  

Science.gov (United States)

The report gives a comprehensive summary of the experience gained and the problems encountered during the Cat-Ox demonstration program. The report outlines the process design and construction, as well as operating experience and problems. Test results and conclusions derived from...

26

Chalk Point Cooling Tower Project: Drift Salinity Experiments.  

Science.gov (United States)

Results of feasibility experiments for determining the mineral content of individual stains on special Sensitized Paper are presented. The stains were formed on the paper by the impaction of laboratory generated salt water droplets. Of the techniques exam...

1979-01-01

27

A Latent Variable Approach for Meta-Analysis of Gene Expression Data from Multiple Microarray Experiments  

UK PubMed Central (United Kingdom)

BackgroundWith the explosion in data generated using microarray technology by different investigators working on similar experiments, it is of interest to combine results across...Full Text Available

28

Vibration experiment for a three-loop PWR reactor building  

Energy Technology Data Exchange (ETDEWEB)

Forced vibration experiment has been conducted for the reactor building of Sendai Unit 1 nuclear power plant. The beam vibrational behaviors of the outer shielding building and the internal concrete structure have been observed by using a 50 tf vibration for low frequency region, and a 10 tf vibration for high frequency region, respectively. The outline of the experimental methods, the data handling system and the major results of experiment are described. The experimental results were simulated by an analytical model. The proper vibrational frequency and the vibration modes obtained by the analysis were compared with those obtained by the experiment. By these comparisons, the adequacy of the analytical method employed for the design was confirmed.

1983-12-01

29

Tachyons revisited  

International Nuclear Information System (INIS)

An apparently significant result in an experiment to search for tachyons in the interval of time immediately preceding in the arrival of air showers of energy approximately 10"1"5 eV is considered. Several similar experiments have been completed, all of which have yielded null results. The original data of the foregoing reference have been re-examined and it is shown that an artifact of the apparatus was contributing to the original apparently significant results. (orig./BJ).

30

Analysis of the pressure variation phenomena during condensation oscillation and chugging  

International Nuclear Information System (INIS)

To get a better understanding of the condensation oscillation and chugging process during blowdown of a BWR after a LOCA a large number of large scale pressure suppression experiments have been performed in several countries. ECN has performed a detailed analysis of the results of one of these experiments, e.g. the DAS M10 experiment of GKSS. This analysis includes the following aspects: Power Spectral Density (PSD) analysis of the data, analysis of the acoustic frequencies of the downcomers and an analysis of the eigenfrequencies of the downcomers. The results of these analyses and an evaluation are given in this paper. It is shown that all dominant frequencies in the experimental results can be correlated with the vent-acoustic or eigenfrequencies. (orig.).

1985-08-01

31

X-15 Research Results: Chapter 9  

Science.gov (United States)

... hypersonic aerodynamic force, or the space-equivalent region. Some of these experiments change the X-15 from a research airplane to a kind of space probe, ...

32

Lipid Peroxidation and Antioxidant Defense ... - LSDA - Experiment  

Science.gov (United States)

Apr 21, 2011 ... The system of lipid peroxidation reacts regularly to adverse effects and results in enhancement of lipid peroxidation and build-up of LPO ...

33

Beyond Boomer Meets NextGen: Examining Mentoring Practices among Pennsylvania Academic Librarians  

British Library Electronic Table of Contents (United Kingdom)

A survey to assess mentoring experiences and attitudes towards work of Pennsylvania academic librarians was conducted in September 2006 with questions concerning mentoring experiences, work experiences, and attitudes towards work. Results of the survey are analyzed for differences among those librarians responding, especially generational differences, and implications for professional associations when developing mentoring programs are discussed.

2011-01-01

34

Diffraction Experiments at the IBR-2 Pulsed Reactor with Methane Cold Neutron Source  

CERN Document Server

A new methane cold neutron source has been tested at the IBR-2 pulsed reactor at the Frank Laboratory of Neutron Physics. In a paper the results of experiments at neutron diffractometers HRFD and DN-2 which are placed at the IBR-2 from the methane moderator side are given. A comparison with the results obtained with the conventional water comb-like moderator is performed. The perspectives of the cold source for various kinds of neutron diffraction experiments, including atomic and magnetic structural analysis and real time experiments are discussed. It is shown, that for a huge number of the experiments which are performing at both HRFD and DN-2 the methane cold neutron source provides the better conditions than water comb-like moderator.

2000-01-01

35

Analysis of steam generator loss-of-feedwater experiments with APROS and RELAP5/MOD3.1 computer codes  

Energy Technology Data Exchange (ETDEWEB)

Three experiments were conducted to study the behaviour of the new horizontal steam generator construction of the PACTEL test facility. In the experiments the secondary side coolant level was reduced stepwise. The experiments were calculated with two computer codes RELAP5/MOD3.1 and APROS version 2.11. A similar nodalization scheme was used for both codes so that the results may be compared. Only the steam generator was modeled and the rest of the facility was given as a boundary condition. The results show that both codes calculate well the behaviour of the primary side of the steam generator. On the secondary side both codes calculate lower steam temperatures in the upper part of the heat exchange tube bundle than was measured in the experiments. (orig.) 4 refs.

1997-12-01

36

Analysis of steam generator loss-of-feedwater experiments with APROS and RELAP5/MOD3.1 computer codes  

International Nuclear Information System (INIS)

Three experiments were conducted to study the behaviour of the new horizontal steam generator construction of the PACTEL test facility. In the experiments the secondary side coolant level was reduced stepwise. The experiments were calculated with two computer codes RELAP5/MOD3.1 and APROS version 2.11. A similar nodalization scheme was used for both codes so that the results may be compared. Only the steam generator was modeled and the rest of the facility was given as a boundary condition. The results show that both codes calculate well the behaviour of the primary side of the steam generator. On the secondary side both codes calculate lower steam temperatures in the upper part of the heat exchange tube bundle than was measured in the experiments. (orig.).

1995-09-10

37

Stopping or Reporting Early for Positive Results in Randomized Clinical Trials: The National Cancer Institute Cooperative Group Experience From 1990 to 2005  

UK PubMed Central (United Kingdom)

Randomized clinical trials are designed with stopping boundaries to guide data monitoring committees with their decision making concerning ongoing trials. In particular, when extremely positive results...Full Text Available

2009-04-01

38

On the probability of flucton production in the 1p-shell nuclei  

International Nuclear Information System (INIS)

Probabilities of flucton production have been calculated for the 1p-shell nuclei and its modification by the Yastrov method. The results obtained are in a qualitative agreement with the data resulting from the analysis of experiment in an assumption of a flucton mechanism of proton-nuclear inclusive reactions with the production of cumulative particles.

39

Natural convection cooling of liquid metal systems  

International Nuclear Information System (INIS)

The recognition that natural convection offers the prospect of an important inherent safety feature for liquid metal cooled reactor systems has provided the impetus for a world-wide research effort over the past decade. Whilst this research has been based on experiment, both plant experiments and out-of-pile experiments, the enormous advances in the development of computing power in recent years have enabled complementary programmes of mathematical modelling through numerical simulation of the transport equations in three spatial dimensions. These not only offer considerable promise for the designer in projecting the behaviour from experiments and prototype plant to full scale plant, they have also proved to be of considerable value in helping us to interpret and understand the results of the experiments themselves. This paper attempts to review the progress ...

40

Vibration experiment for a three-loop PWR reactor building  

International Nuclear Information System (INIS)

Forced vibration experiment has been conducted for the reactor building of Sendai Unit 1 nuclear power plant. The beam vibrational behaviors of the outer shielding building and the internal concrete structure have been observed by using a 50 tf vibration for low frequency region, and a 10 tf vibration for high frequency region, respectively. The outline of the experimental methods, the data handling system and the major results of experiment are described. The experimental results were simulated by an analytical model. The proper vibrational frequency and the vibration modes obtained by the analysis were compared with those obtained by the experiment. By these comparison, the adequacy of the analytical method employed for the design was confirmed. (Aoki, K.).

1983-01-01

41

Optimization of an interlaboratory program for the certification of a multi-element plagiogneiss reference material  

International Nuclear Information System (INIS)

A sample of garnet-biotite plagiogneiss, GBPg-1 is currently being developed as a certified reference material at the Vinogradov Institute of Geochemistry. It was used as the sample that was distributed round 7 of International Proficiency Testing Program (GeoPT7) and was analyzed by 76 geoanalytical laboratories around the world. Twenty Russian laboratories involved in the interlaboratory experiment also analyzed GBPg-1. The resultant analytical data obtained from these two experiments has allowed GBPg-1 to be certified as a state standard sample for 50 elements. It also enabled a comparison of the quality of data developed by the Russian and international geoanalytical laboratories, to optimize the outcome of this interlaboratory experiment.

2003-02-03

42

Experience of HWR nuclear fuel fabrication technology development in Korea  

Energy Technology Data Exchange (ETDEWEB)

Since January, 1981, the project of development of nuclear fuel fabrication technology for Wolsung reactor (CANDU type) was undertaken by KAERI(Korea Advanced Energy Research Institute) and successfully fulfilled with loading 24 fuel bundles made by KAERI in Wolsung reactor in September, 1984. On the basis of this accumulated technology and experience, mass production plan to supply all the nuclear fuels for Wolsung reactor is under way. In this presentation, the Korean experience in the development of the nuclear fuel fabrication technology, safety and performance evaluation of KAERI fuel and the results of irradiation of KAERI fuels in Wolsung reactor will be described.

1985-07-01

43

Experience of HWR nuclear fuel fabrication technology development in Korea  

International Nuclear Information System (INIS)

Since January, 1981, the project of development of nuclear fuel fabrication technology for Wolsung reactor (CANDU type) was undertaken by KAERI(Korea Advanced Energy Research Institute) and successfully fulfilled with loading 24 fuel bundles made by KAERI in Wolsung reactor in September, 1984. On the basis of this accumulated technology and experience, mass production plan to supply all the nuclear fuels for Wolsung reactor is under way. In this presentation, the Korean experience in the development of the nuclear fuel fabrication technology, safety and performance evaluation of KAERI fuel and the results of irradiation of KAERI fuels in Wolsung reactor will be described.

1985-10-29

44

A study of aging effects in gas proportional detectors at the BAC calorimeter of the ZEUS experiment  

Energy Technology Data Exchange (ETDEWEB)

The multicell proportional chambers at the backing calorimeter of the ZEUS experiment at the storage ring HERA are supplied with a gas mixture of Ar/CO[sub 2] by an open gas system. Flow proportional counters with the build-up [sup 55]Fe sources are used as gas system monitoring detectors. The ZEUS experiment is planned to collect data for about 10 years. Therefore, the lifetime of the Ar/CO[sub 2] mixture should be known. In this paper, the results of laboratory tests and preliminary measurements of the aging effects for monitoring counters are presented. ((orig.))

1994-09-01

45

Steady-state thermohydraulic studies in seven-pin bundle out-of-pile experiments: nominal and distorted geometry tests  

International Nuclear Information System (INIS)

Two sets of experiments have been performed in sodium with two seven pin electrically heated bundles: the first with a nominal arrangement, the second with one dummy pin enlarged 20% in diameter in peripheral position. In this paper a rapid review of experimental results and theoretical works, related to the temperature distribution in these geometries, is presented together with a short description of the developed test section technology.

1979-11-01

46

Shaping pulses using frequency conversion with a modulated picosecond free electron laser  

Energy Technology Data Exchange (ETDEWEB)

Computer simulations and experiments indicate that we can shape the infrared picosecond pulses of the Mark III FEL in amplitude, frequency, and phase. Strongly modulated fundamental and second harmonic pulses have been generated by operating the Mark III FEL in the regime of strong sideband growth. In this paper, we present the results of simulations and experiments for second harmonic generation with fundamental inputs from 2 to 3 {mu}m.

1995-12-31

47

Real time closed orbit correction system  

Energy Technology Data Exchange (ETDEWEB)

We describe a global closed orbit feedback experiment, based upon a real time harmonic analysis of both the orbit movement and the correction magnetic fields. The feedback forces the coefficients of a few harmonics near the betatron tune to vanish, and significantly improves the global orbit stability. We present the results of the experiment in the UV ring using 4 detectors and 4 trims, in which maximum observed displacement was reduced by a factor of between 3 and 4. 4 refs., 3 figs.

1989-01-01

48

Radioactive source management in Daya Bay NPP  

International Nuclear Information System (INIS)

'Small radioactive source results in big accident' have occurred repeatedly in China and worldwide alike. Radioactive source management is one of the key activities for a nuclear power plant to maintain its good safety record and image to the public. From aspects of establishing the management system, centralized storage, periodic accounting, performing whole process control to the source usage and experience feedback etc., the author reports the practice and experience of radioactive source management in Daya Bay Nuclear Power Plant

1999-11-01

49

Improved FNAL linac beam choppers  

Energy Technology Data Exchange (ETDEWEB)

A discussion is presented of the 750-KeV chopper experience with both proton and negative ion beams and the ability of these systems to tailor the Linac beam to the diverse requirements of its users; normal accelerator injection, neutron therapy beam, and electron cooling experiments. This flexibility plus a cleaner beam pulse, improved thyratron operation, and mechanical modularity are the results of recent improvements. Additional benefits have been increased reliability and ease of service to the 750-KeV chopper. 3 refs.

1981-06-01

50

Experimental regulation of advanced solar central receivers. Final report  

Energy Technology Data Exchange (ETDEWEB)

An investigation of natural convection losses from cavity-type solar central receivers is described and results are given. The approach followed was that of a fundamental experimental study in a simple cavity subject to well controlled boundary conditions. The Laser Doppler Velocimeter proved to be a useful technique to measure the velocity profiles associated with natural convection. Visualization techniques provided an understanding of the general behavior of the flow, particularly in three dimensional experiments. Experiments on systems of high Rayleigh numbers are described. (LEW)

1981-06-01

51

Searching for the Neutrino Mixing Angle Theta-13 at Reactors  

CERN Document Server

Two neutrino mixing angles have been measured, and much of the neutrino community is turning its attention to the unmeasured mixing angle, $\\quq$, whose best limit comes from the reactor neutrino experiment CHOOZ.\\cite{bib:chooz} New two detector reactor neutrino experiments are being planned, along with more ambitious accelerator experiments, to measure or further limit $\\quq$. Here I will overview how to measure $\\quq$ using reactor neutrinos, mention some experiments that were considered and are not going forward, and review the current status of four projects: Double Chooz in France, Daya Bay in China, RENO in South Korea and Angra in Brazil. Finally I will mention how the neutrino observer can gauge progress in these projects two years from now as we approach the times corresponding to early estimates for new results.

2007-01-01

52

Effect of structure and thermal properties of the electrically heated rod on transient thermal-hydraulic experiment  

International Nuclear Information System (INIS)

The electrically heated rod is usually used as a substitute for fuel rod in thermal-hydraulic experiment. However, the different structure and thermal properties between nuclear fuel rod and electrically heated rod result in different steady-state distribution of temperature and stored energy and different response to thermal-hydraulic in simulation transient experiment. This paper analyses the effect of structure and thermal properties differences between nuclear fuel rod and electrically heated rod on experiment, and then introduce a feasible method, i.e. electric power is controlled by a program, to reduce the differences between the transient responses of nuclear fuel rod and electrically heated rod. At the same time, this paper points out the limits of the method. (authors)

2004-09-01

53

Demonstration experiments of volume measurement technique for large scale input accountancy tank  

International Nuclear Information System (INIS)

Tank calibration experiments have been carried out using a mock-up input accountancy tank with the object of developing a high accuracy solution volume measurement technique for Rokkasho Reprocessing Plant (RRP). The experimental parameters such as temperature, solution density, off gas pressure and so on have been fluctuated in the calibration experiments in order to evaluate the influence on the solution volume measurement. As a result, it was confirmed that the solution volume measurement error of the mock-up tank was within #+-#0.04% (at full volume) using careful data correction technique for measured data. For the high accuracy volume measurement at RRP, it is important to correct data properly taking account of the actual conditions such as uncontrollable ambient temperature that are different from the experiment. (author)

2000-12-07

54

Network security defence methods in IHEP  

International Nuclear Information System (INIS)

This article is about the network security defence method and technique at IHEP. Including: the experience, research result and application in network outlet security, server security, local network security, network security monitoring and collecting evidence, anti-virus etc

2002-12-01

55

Mutagenic activity of disinfection by-products.  

UK PubMed Central (United Kingdom)

Data on raw water quality, disinfection treatment practices, and the resulting mutagenic properties of the treated water were compiled from pilot- and full-scale treatment experiments to evaluate that...Full Text Available

1986-11-01

56

Method of pipe whip and impact analyses  

Energy Technology Data Exchange (ETDEWEB)

We successfully reproduce one of the French pipe whip experiments with the computer code WIPS. The WIPS results are in excellent agreement with the experimental data and the French computer code TEDEL. This justifies the use of its pipe element in conjunction with its U-bar element in a simplified method of impact analyses.

1983-11-21

57

Horizontal steam generators: Problems and prospects  

British Library Electronic Table of Contents (United Kingdom)

Main results of the 40-year experience gained from operation of horizontal steam generators in VVER-type reactor installations used in Russia and many foreign countries are described. Existing unresolved problems are pointed out.

2011-01-01

58

Experience of static electrification in power transformer  

Energy Technology Data Exchange (ETDEWEB)

This document is a discussion of a static electrification event in each of the 1050 MVA units installed at the Koeburg Nuclear Power Plant in South Africa. Results of a tear-down inspection performed after the event are given, as is an analysis of the event. A number of photographs are included.

1995-05-01

59

Dissociation dynamics of methylal  

Energy Technology Data Exchange (ETDEWEB)

The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.

1999-08-01

60

DESIGN MANUAL: SWIRL AND HELICAL BEND POLLUTION CONTROL DEVICES  

Science.gov (United States)

This design manual contains descriptions of design procedures and operating experience to date, including results obtained, for secondary flow pollution control devices. Two types of combined sewer overflow regulators are described: the swirl and the helical bend regulator/separa...

61

Cross sections and spin asymmetries in vector meson leptoproduction  

CERN Document Server

Light vector meson leptoproduction is analyzed on the basis of the generalized parton distributions. Our results on the cross section and spin effects are in good agrement with experiment at HERA, COMPASS and HERMES energies. Predictions for $A_{UT}$ asymmetry for various reactions are presented.

2009-01-01

62

Correspondence of Ultrasound Elasticity Imaging to Direct Mechanical Measurement in Aging DVT in Rats  

UK PubMed Central (United Kingdom)

Previous ultrasound elasticity imaging experiments supported a generally accepted concept that the hardness of deep venous thrombi increases with thrombus aging. Results also showed that this...Full Text Available

2005-10-01

63

CP Violation with Bs -> J/Psi phi at the Tevatron  

CERN Document Server

Recent results using B_s -> J/Psi phi decays for measuring the CP violating phase, phi_s, and the decay width difference for the two mass eigenstates, Delta Gamma_s, are presented from the CDF and D0 experiments at the Fermilab Tevatron collider.

2011-01-01

64

Evaluation of light-water-moderated, mixed-oxide, hexagonal pitch lattices  

International Nuclear Information System (INIS)

The use of previously measured mixed-oxide (MOX) fuel systems as benchmarks can be valuable tool in computational analysis and quality assurance efforts. The Fissile Materials Disposition Program (FMDP) has identified these experiments as potential benchmarks, or standards, for VVER's employing MOX fuel. Standards for the analysis of these benchmark experiments were based on those used in the recent compilation International Handbook of Evaluated Criticality Safety Benchmark Experiments begun in 1992 by the U.S. Department of Energy. The Los Alamos National Laboratory's archives were explored for log-book records of these experiments without success. These experiments were the first to use MOX fuel in light water. Three approach-to-critical experiments were performed using fuel rods at various pitches and different plutonium-oxide concentrations. A parallel ...

1997-11-16

65

Development of pyro-separation technology based on molten salt electrolysis  

International Nuclear Information System (INIS)

In order to effectively recover uranium, rotation speed of solid cathode was examined, and effect of uranium concentration and current density on electrodeposition were confirmed. And the potentiostatic and galvanostatic electrorefining experiments were conducted. Element used in the experiments were Zr, Nd, La chlorides. The reduction potentials of chlorides metals on liquid Cd cathode were measured by cyclic voltammetry experiments. The electrowinning experiments were performed in order to recover small amounts of uranium in salt. Experimental set-up for the batch type reductive extraction experiments were developed and installed. On the base of experimental results of batch type, multi-stage extraction equipment was set-up, and optimum number of stage and recover yield were measured. In the oxidative extraction study is examine selective separation behavior ...

2010-10-01

66

Shell coal gasification plant (SCGP-1) environmental performance results  

Energy Technology Data Exchange (ETDEWEB)

Environmental studies in slip-stream process development units at SCGP-1, Shell's advanced coal gasification demonstration plant, located near Houston, Texas, have demonstrated that the gas and water effluents from the Shell Coal Gasification Process (SCGP) are environmentally benign on a broad slate of coals. This report presents the results of those environmental studies. It contains two major subjects, which describe, respectively, the experiments on gas treating and the experiments on water treating. Gas treatment focused on the performance of aqueous methyldiethanolamine (MDEA) and sulfinol-M. 8 refs., 24 figs., 13 tabs.

1991-07-01

67

Initial results from 50mm short SSC dipoles at Fermilab  

Energy Technology Data Exchange (ETDEWEB)

Several short model SSC 50 mm bore dipoles are being built and tested at Fermilab. Mechanical design of these magnets has been determined from experience involved in the construction and testing of 40 mm dipoles. Construction experience includes coil winding, curing and measuring, coil end part design and fabrication, ground insulation, instrumentation, collaring and yoke assembly. Fabrication techniques are explained and construction problems are discussed. Similarities and differences from the 40 mm dipole tooling and management components are outlined. Test results from the first models are presented. 19 refs., 12 figs.

1991-03-01

68

Depression among Alumni of Foster Care: Decreasing Rates through Improvement of Experiences in Care  

Science.gov (United States)

The Northwest Foster Care Alumni Study examined the relation between experiences in foster care and depression among young adults who spent at least a year in foster care as adolescents. Results indicate that preparation for leaving foster care, nurturing supports from the foster family, school stability, access to tutoring, access to therapeutic service and support, and a shorter and more stable placement history were associated with a lower probability of depression in young adulthood. Results provide evidence that suggest ways to improve practice to decrease rates of depression among alumni of care. (Contains 2 tables.)

2008-12-01

69

ORALLOY (93.2 235U) METAL CYLINDER WITH BERYLLIUM TOP REFLECTOR  

International Nuclear Information System (INIS)

A variety of critical experiments were constructed of enriched uranium metal during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, one experiment was comprised of a stack of approximately 7-inch-diameter metal discs. The bottom of the stack consisted of uranium with an approximate height of ...

70

TRACE code modeling of the horizontal steam generator of the PACTEL facility and calculation of a loss-of-feedwater experiment  

British Library Electronic Table of Contents (United Kingdom)

This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exc...

2010-01-01

71

Fracture behavior under dynamic biaxial stress on magnesium alloy  

Energy Technology Data Exchange (ETDEWEB)

We conduct the static and dynamic loading fracture experiments on magnesium alloy (AZ31B) under the equitable and inequitable biaxial stress. We process specimens as cross type with cracks. There are different kinds of cracks defined by their crack angles. By using a hydraulic high-speed biaxial experiment machine, we put the equitable and inequitable stresses on the specimen. We analyze results using the caustic method. The experiments reveal a few important results. There is negative correlation between the fracture toughness value and the plate thickness in the magnesium alloy sheet specimen. The fracture toughness value decrease in the case the crack has the angle different from the loading direction. The fracture toughness value decreases significantly under the inequitable biaxial stress. (orig.)

2004-07-01

72

Experience with the identification and tuning of excitation system parameters at the second nuclear power plant of Taiwan Power Company  

Energy Technology Data Exchange (ETDEWEB)

Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer`s constants, the authors first modify the manufacturer`s constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer.

1996-05-01

73

Experience with the identification and tuning of excitation system parameters at the second nuclear power plant of Taiwan Power Company  

International Nuclear Information System (INIS)

Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer's constants, the authors first modify the manufacturer's constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer.

1995-07-23

74

Catalytic tar removal from biomass producer gas with secondary air  

Energy Technology Data Exchange (ETDEWEB)

The effect of air addition on biomass tar conversion in catalytic packed bed crackers was studied using both an isothermal micro reactor and a fluidised bed bench scale biomass gasification set up with down stream tar crackers. The micro reactor was applied for experiments with artificial biomass producer gas containing naphthalene as a model tar compound. Experiments were carried out with inert silica and catalytically active calcined dolomite bed material both with and without air addition. Experimental results with real tar from the fluidised bed bench scale gasification set up were in qualitative agreement with results from the micro reactor experiments. (author)

1997-12-31

75

The Daya Bay reactor neutrino experiment  

CERN Document Server

The Daya Bay reactor neutrino experiment

2008-01-01

76

Statistical Analysis of Designed Experiments  

CERN Document Server

Statistical Analysis of Designed Experiments

2010-01-01

77

Optimization of Valve Disc Using Orthogonal Array and Kriging Model  

Science.gov (United States)

A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing. Currently, FEA is often used to predict the safety in the design of valve disc. Also, the study about the affection of butterfly valve's disc to the valve flow characteristics by using CFD has been done by many researchers. Along with the development of computer technique, design and analysis of computer experiments has becoming more and more important in engineering design and optimization. Hereinto Kriging model is one popular analysis approach for the purpose of creating a cheap ``meta-model'' as a surrogate to a computationally expensive simulation model. In this paper, the numerical analysis considered the strength, pressure loss coefficient and weight of valve disc simultaneously is investigated to improve the shape of a traditional butterfly valve disc. Firstly, an initial model of butterfly valve is made to evaluate the performance of the valve disc by using CFD ...

2008-10-01

78

TRACE code modeling of the horizontal steam generator of the PACTEL facility and calculation of a loss-of-feedwater experiment  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exchange tubes were studied in detail. Different nodalization options were introduced. In the simulation of PACTEL ...

2010-11-15

79

TRACE code modeling of the horizontal steam generator of the PACTEL facility and calculation of a loss-of-feedwater experiment  

International Nuclear Information System (INIS)

This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exchange tubes were studied in detail. Different nodalization options were introduced. In the simulation of PACTEL ...

2010-11-01

80

Busted Butte report on laboratory radionuclide migration experiments in non-welded tuff under unsaturated conditions  

Energy Technology Data Exchange (ETDEWEB)

Three blocks of non-welded tuff, one nominally one cubic foot (trial block) and the other two, nominally one cubic metre (1 m{sup 3}), were excavated from the Busted Butte Test Facility on the Nevada Test Site and transported to the Atomic Energy of Canada Limited Whiteshell Laboratories in Pinawa, Manitoba. The trial block and one of the 1-m{sup 3} blocks were used for unsaturated flow experiments. The remaining 1-m{sup 3} block is being used for saturated flow experiments and will be reported on separately. After a vertical flow of synthetic transport solution was set up under unsaturated conditions, a suite of conservative and chemically reactive radionuclide tracers was injected at volumetric flow rates of 20 mL/hr in the trial block, and 10 mL/hr in the 1-m{sup 3} block. The duration of the migration experiment in the trial block was 87 days, while the migration experiment in the 1-m{sup 3} block ...

2002-11-01

81

Nuclear multifragmentation experiment at the KEK 12 GeV PS. The first results of the KEK-PS E337 experiment  

Energy Technology Data Exchange (ETDEWEB)

A KEK-PS experiment E337 `Angular correlation of intermediate mass fragments emitted from the target multifragmentation reactions with 12 GeV protons` is an extension of the E288 performed a few years ago. The E288 revealed that the proton-induced target multifragmentation reactions at 12 GeV showed quite interesting phenomena such as 70 degree peaking angular distributions for intermediate mass fragments. In December, 1955, the test experiment with 12 GeV protons was started at KEK using this newly constructed counter array of 37 Bragg Curve Counters. The main production experiment was performed in April and May in 1996 after debugging the new counter system and DAQ system, as well as EP1-B beam line. Data with Au, Tm, Sm and Ag targets were successfully accumulated. The data are in the analysis stage, and several interesting features of high energy nuclear reactions have already been seen. (G.K.)

1997-05-01

82

Hot water extraction with in situ wet oxidation: Kinetics of PAHs removal from soil  

International Nuclear Information System (INIS)

Finding environmentally friendly and cost-effective methods to remediate soils contaminated with polycyclic aromatic hydrocarbons (PAHs) is currently a major concern of researchers. In this study, a series of small-scale semi-continuous extractions - with and without in situ wet oxidation - were performed on soils polluted with PAHs, using subcritical water (i.e. liquid water at high temperatures and pressures, but below the critical point) as the removal agent. Experiments were performed in a 300 mL reactor using an aged soil sample. To find the desorption isotherms and oxidation reaction rates, semi-continuous experiments with residence times of 1 and 2 h were performed using aged soil at 250 deg. C and hydrogen peroxide as oxidizing agent. In all combined extraction and oxidation flow experiments, PAHs in the remaining soil after the experiments were almost undetectable. In combined extraction and ...

2006-09-01

83

Development of HT-9 for liquid-metal reactor components  

International Nuclear Information System (INIS)

Alloy HT-9 is being used for both duct and cladding applications in advanced liquid-metal reactor (LMR) experiments. This tempered martensitic steel was selected for use as an LMR core component material primarily because of its excellent resistance to radiation-induced swelling. Experiments conducted in the Fast Flux Test Facility (FFTF) at 410 degree C and exposures in the range of 150 to 175 displacements per atom (dpa) have shown that Ht-9 exhibits only a 0.2 to 0.3% increase in volume. Cold-worked austenitic steels exhibit volumetric increases of 20 to 30% at 410 degree C, Alloy HT-9 is being used for a series of fuel pin experiments in the FFTF, and these tests have achieved a burnup of 175 MWd/kg metal and a fluence of 25 x 10"2"2 n/cm"2 (E > 0.1 MeV) without fuel pin breach. The high confidence placed in HT-9 is based on a wide series of in- and ex-reactor experiments. Test ...

1989-11-26

84

Tachyons revisited - comments on a search for faster-than-light particles  

International Nuclear Information System (INIS)

An apparently significant result in an experiment to search for tachyons in the interval of time immediately preceding the arrival of air showers of energy greater than 10"1"5 eV has been reported by Clay and Crouch (Clay, R.W. and Crouch, P.C., 1974, Nature, vol.248,28-30). Several similar experiments have been completed, all of which have yielded null results. The original data of Clay and Crouch have been re-examined and it is shown that an artifact of the apparatus was contributing to the original, apparently significant, result. An upper limit estimate shows that the number of tachyons is less than the number of hadrons of energy greater than 100 GeV in showers of average size N = 6 x 10"5 particles. (author).

85

Natural circulation decay heat removal experiments and analysis in an LMFBR fuel assembly  

International Nuclear Information System (INIS)

Water flow experiments were conducted on natural circulation decay heat removal with an electrically heated 91-rod bundle. Experimental results were compared with analytical predictions to provide thermal hydraulic characteristics for LMFBR Fuel assemblies under a low flow, typical of the natural circulation regime. The results revealed that, at low flow rate region (Re<1,200), axial friction loss in a heated bundle increases with buoyancy effect. The radial temperature profile provides some insight regarding the concept that coolant redistribution would occur. COBRA-V-I predictions are successfully proved validity in comparison with experimental results.

1982-07-01

86

Cumulative effect of X-ray radiation and inflammatory reaction on the circadian rhythm of tyrosine aminotransferase in the liver of mice  

International Nuclear Information System (INIS)

The activity of tyrosine aminotransferase (TAT) in the liver of mice subjected simultaneously to ionizing radiation and to local inflammatory process showed in the first 24 hours of the experiment statistically significant changes resulting from summation of the harmful effects of both factors. In the second 24-hour period an evident tendency was observed for return of a normal circadian rhythm of the enzyme. This points to presence of an endogenous mechanism of suppression of the manifestations of significant desynchronization of the circadian rhythm. The paper contains also a trial of mathematical analysis of changes in TAT activity in the circadian rhythm, a description and analysis or the suppression process, qualitative and quantitative determination of the phenomenon of cumulation of the effects of powerful stress factors acting on the animal organism. The obtained results were compared with the ...

1980-01-01

87

Investigation of pollutant formation of Sweet Sorghum-lignite (Orhaneli) mixtures in fluidised beds  

Energy Technology Data Exchange (ETDEWEB)

Most of the Turkish lignites have undesired fuel properties and they are extremely polluting. In this study, Sweet Sorghum was chosen as the energy plant. Combustion experiments of lignite and lignite-Sweet Sorghum mixtures were carried out in a fluidised bed system. The fuel-feeding ratio was set such that the thermal output of the system remained constant. Addition of Sweet Sorghum to the lignite reduces the pollutant concentration. The results were supported by experimental results.

2004-07-01

88

Formation of streamers in nitrogen and dry air; Vorming van streamers in stikstof en lucht  

Energy Technology Data Exchange (ETDEWEB)

The results of a time-resolved study of the avalanche and streamer formation phases leading to breakdown in atmospheric nitrogen and dry air. Results of experiments and two-dimensional simulations are presented. It is shown what processes are responsible for the formation of a streamer. The trends of externally measured quantities correspond with those predicted by our model. 3 figs., 5 refs.

1997-01-01

89

Demonstration of neutron radiography and computed tomography at the University of Texas thermal neutron imaging facility  

Energy Technology Data Exchange (ETDEWEB)

A thermal neutron imaging facility for real-time neutron radiography and computed tomography has recently been developed and built at the University of Texas TRIGA reactor. Herein the authors present preliminary results of radiography and tomography test experiments. These preliminary results showed that the beam is of high quality and is suitable for radiography and tomography applications. A more detailed description of the facility is given elsewhere.

1999-09-01

90

Demonstration of neutron radiography and computed tomography at the University of Texas thermal neutron imaging facility  

International Nuclear Information System (INIS)

A thermal neutron imaging facility for real-time neutron radiography and computed tomography has recently been developed and built at the University of Texas TRIGA reactor. Herein the authors present preliminary results of radiography and tomography test experiments. These preliminary results showed that the beam is of high quality and is suitable for radiography and tomography applications. A more detailed description of the facility is given elsewhere

1999-06-06

91

DECOVALEX - Mathematical models of coupled T-H-M processes for nuclear waste repositories. Report of phase III  

Energy Technology Data Exchange (ETDEWEB)

This report presents the methodologies and results of the field/laboratory experiments and mathematical modeling defined for the phase III of the project. Results from test cases 2-6 are given in separate chapters of the report (which have been indexed separately), and the last chapter discusses the lessons learned from the three phases of the DECOVALEX project.

1995-12-01

92

Correlations between D and Dbar mesons in high energy photoproduction  

Energy Technology Data Exchange (ETDEWEB)

Over 7000 events containing a fully reconstructed D{bar D} pair have been extracted from data recorded by the FOCUS photoproduction experiment at Fermilab. Preliminary results from a study of correlations between D and {bar D} mesons are presented. Correlations are used to study perturbative QCD predictions and investigate non-perturbative effects. We also present a preliminary result on the production of {psi}(3770).

2002-11-13

93

The weight of obesity in evaluating others: a mere proximity effect.  

Science.gov (United States)

Previous research demonstrates that we tend to derogate individuals who are perceived to be in a social relationship with stigmatized persons. Two experiments examined whether this phenomenon also occurs for individuals seen in the presence of an obese person and whether a social relationship is necessary for stigmatization to spread. The results from both experiments revealed that a male job applicant was rated more negatively when seen with an overweight compared to a normal weight female and that just being in the mere proximity of an overweight woman was enough to trigger stigmatization toward the male applicant. Experiment 2 examined possible moderating effects of the proximity finding. Applicants seated next to heavy (vs. average weight) individuals were denigrated consistently regardless of the perceived depth of the relationship, the participant's anti-fat attitudes or gender, and whether or not ...

2003-01-01

94

Startup of the experimental physics industrial control system at NSTX  

Energy Technology Data Exchange (ETDEWEB)

The Experimental Physics Industrial Control System (EPICS) is a set of software which is being used as the basis of the National Spherical Torus Experiment's (NSTX) Process Control System, a major element of the NSTX's Central Instrumentation and Control System. EPICS is a result of a co-development effort started by several US Department of Energy National Laboratories. EPICS is actively supported through an international collaboration made up of government and industrial users. EPICS' good points include portability, scalability, and extensibility. A drawback for small experiments is that a wide range of software skills are necessary to get the software tools running for the process engineers. The authors' experience in designing, developing, operating, and maintaining NSTX's EPICS (system) will be reviewed.

1999-12-17

95

Radiation imposed limits on superconducting magnets: A data base for copper stabilizers  

Energy Technology Data Exchange (ETDEWEB)

Two of eight differently prepared copper stabilizer samples, previously irradiated in the RTNS-II at LLNL, the IPNS-1 and the BSR at ORNL, have been irradiated to a fluence of 1.33 /times/ 10/sup 22/ n/m/sup 2/ at RTNS-II. During the course of the irradiation the samples were periodically removed (without warming) for measurements of the transverse magnetoresistance and returned for continued irradiation. This experiment extends the range of neutron-irradiation-induced resistivity by a factor of five over the previous experiments. A simple model is developed which reproduces the magnetoresistance results of all the experiments to an accuracy of 2.5%. 13 refs., 6 figs.

1987-10-28

96

Preliminary Calculations of the Radiation Damage of the Permanent Magnets for TRADE (TRiga Accelerator Driven Experiment)  

CERN Document Server

Monte Carlo calculations of proton irradiation of permanent magnets for the TRADE experiment have been performed. An irradiation dose of about 4´106 Gy/yr/mA has been estimated due to beam losses in normal operating conditions. Existing experimental results indicate that this irradiation level may induce a considerable demagnetization: in fact, a dose of 6´107 Gy induces a remanence loss of 0.3 % on samples of Sm2Co17 magnets, which are the most resistant type. More detailed calculations with the final design of the magnets and of the beam line are suggested, to determine if the irradiation levels allowed a reliable operation of the permanent magnets for the entire duration of the TRADE experiment. Damage and gas production rates have also been calculated; the values obtained are very low, thus confirming that the demagnetization process is in great part reversible.

2002-01-01

97

On Essential Incompleteness of Hertz's Experiments on Propagation of Electromagnetic Interactions  

CERN Document Server

The historical background of the 19th century electromagnetic theory is revisited from the standpoint of the opposition between alternative approaches in respect to the problem of interactions. The 19th century electrodynamics became the battle-field of a paramount importance to test existing conceptions of interactions. Hertz's experiments were designed to bring a solid experimental evidence in favor of one of them. The modern scientific method applied to analyze Hertz's experimental approach as well as the analysis of his laboratory notes, dairy and private letters show that Hertz's "\\textit{crucial}" experiments cannot be considered as conclusive at many points as it is generally implied. We found that alternative Helmholtz's electrodynamics did not contradict any of Hertz's experimental observations of transverse components as Maxwell's theory predicted. Moreover, as we now know from recently published Hertz's dairy and private notes, his ...

2005-01-01

98

Nuclear Charge Radius of Lithium-11  

Energy Technology Data Exchange (ETDEWEB)

We have determined the nuclear charge radius of 11Li by high-precision laser spectroscopy. The experiment was performed at the TRIUMF-ISAC facility where the 7Li-11Li isotope shift was measured in the 2s to 3s electronic transition using Doppler-free two-photon spectroscopy with a relative accuracy better than 10 5. The accuracy reached in previous experiments on the other lithium isotopes was improved. Most of the isotope shifts measured in the experiment are due to difference in the mass of the nuclei but small contributions are produced by the change in proton distribution, QED and relativistic effects have to be taken into account as well. By comparing the experimental results with sophisticated atomic calculations of the mass dependent effect the nuclear charge radii of the lithium isotopes are found to decrease monotonically from 6Li to 9Li while the nuclear charge radius of 11Li is about 11% ...

2006-07-01

99

Measurements of K-beta/K-alpha X-ray intensity ratios using VEC beams  

International Nuclear Information System (INIS)

An experiment on the K#beta#/K#alpha# characteristic X-ray intensity ratio in silver was performed at VEC Centre, Calcutta using the #alpha#-beams at energies 40 MeV and 50 MeV employing a Si(Li) detector system on-line. The results show that the K#beta#/K#alpha# X-ray intensity ratio at energies 40 and 50 MeV are 0.215 #+-# 0.006 and 0.216 #+-# 0.006, respectively, which indicates no change with beam energy and in accordance with the earlier reports. The present experiment shows the feasibility of studying the K#beta#/K#alpha# ratios as a function of beam energy in different regions of periodic table. Experiments in elements belonging to the 3d shell and their compounds are suggested to look for the chemical effects and their dependence on #alpha#-energy. (author). 7 refs.

1987-02-03

100

Intermediate Strain-Rate Loading Experiments - Technique and Applications to Ceramics  

Energy Technology Data Exchange (ETDEWEB)

A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.

1999-08-16

101

Growth and transpiration of maize and winter wheat in response to water deficits in pots and plots  

British Library Electronic Table of Contents (United Kingdom)

Pots used for experiments conducted on plants grown in them create rooting environments that are affected by limited soil volume, which can affect various physiological processes, including transpiration, and plant growth. However, the applicability of results from pot experiments to the field has received limited attention. The objective of this study was to compare the growth and transpiration of maize (Zea mays L.) and winter wheat (Triticum aestivum L.) when grown in pots and field plots under various constant water deficits. The experiments were conducted under similar environmental conditions for both pots and plots. Transpirational responses at both transient (RTTr) and daily (RDTr) time scales to a decreasing fraction of available soil water (FASW) were analyzed. For a comparable F...

2011-01-01

102

Experimental study on display-control stereotype and development of human factors guidelines  

Energy Technology Data Exchange (ETDEWEB)

It is very important to develop the design guidelines which can be applicable for Korean operators for the purpose of designing the KSNP more safely. The objective of this project is to provide the standards, guidelines and bases applicable for HF-010 through the within-subject experiment for obtaining Korean operators' population stereotype for direction-of-movement of controls associated with displays on the control panels. Through the survey of researches on display compatibility and the classification of types of displays and controls in the main control room of Uljin units 3 and 4, methods for an experiment on the stereotype were established. Experimental interface prototypes for a total of 108 combinations of display and control types were implemented. Experimental data collection and analysis system was built in association with the interface prototypes. The experiment was performed with participation of 250 ...

2003-01-01

103

Ensuring GRID resource availability with the SAM framework in LHCb  

CERN Document Server

The LHCb experiment has chosen to use the SAM framework (Service Availability Monitoring Environment from EGEE-II) [1] make extensive tests of the LHCb environment at all the accessible grid resources. The availability and the proper definition of the local Computing and Storage Elements, user interfaces as well as the WLCG software environment are checked. The SAM framework is also used to pre-install the LHCb applications in the shared software area provided by each site. The deployment of the LHCb applications is based on a python tool developed inside the experiment. It is used for software management including incremental installation of interdependent packages and clean package removal. After the application software is installed a validation test of the whole MC chain is run. According to the results of the experiment specific SAM tests, the sites are (re)integrated into the LHCb production ...

2008-01-01

104

Effect of radiation on certain animal viruses in liquid swine manure  

International Nuclear Information System (INIS)

The virucidal effect of _6_0Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhoea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy. (author).

1983-01-01

105

Development and validation of a CATHENA fuel channel model for a post-blowdown analysis of the high temperature thermal-chemical experiment CS28-1  

British Library Electronic Table of Contents (United Kingdom)

To form a licensing basis for a new methodology for a fuel channel safety analysis code for CANDU-6 nuclear reactor, a CATHENA model for a post-blowdown fuel channel analysis has been developed, and tested for a high temperature thermal-chemical experiment CS28-1 [Lei, Q.M., 1993. Post-test analysis of the 28-element high-temperature thermal-chemical experiment CS28-1. In: 4th International Conference on Simulation Methods in Nuclear Engineering, Montreal, PQ, 1993]. Pursuant to the objective of this investigation, the current study has focused on understanding the involved phenomena, their interrelations, and how to maintain a good accuracy of the temperature and H2 generation rate prediction without losing the important physics of the involved phenomena. The transient simulation results ...

2009-01-01

106

Determination of two-phase natural circulation interfacial parameters by real-time neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena ...

2003-07-01

107

Determination of two-phase natural circulation interfacial parameters by real-time neutron radiography  

International Nuclear Information System (INIS)

Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena ...

2003-10-05

108

Ab initio study on pressure-induced change of effective Coulomb interaction in superconducting yttrium  

Science.gov (United States)

Ab initio lattice dynamics based on linear response method are performed for high pressure phase of yttrium to describe electron-phonon coupling and subsequent superconducting behavior. The critical temperature Tc in fcc-Y increases monotonically with pressure up to 9.25 K at 31 GPa, which is quantitatively in excellent agreement with two quasihydrostatic experiments and is qualitatively compatible with recent experiments. The excellent agreement with experiments gives us a better understanding of the effective pseudopotential ?* as well as spectral function ?2(?)F(?) in yttrium. These results demonstrate that there exists strong electron-phonon coupling in Y within the studied pressure regime, and for lower pressure electron correlation becomes stronger. Generally, it is found that superconductivity in yttrium under pressure can be described quantitatively within standard theory of phonon-mediated ...

2010-01-01

109

Uncertainties of radionuclide migration parameter values obtained from in-situ tracer experiments  

International Nuclear Information System (INIS)

One of the key issues in safety assessment of high-level nuclear waste disposal is evaluating the effects of uncertainty inherent in radionuclide migration parameter values. In this paper, radionuclide transport parameter values and error variances (uncertainties) from in-situ tracer experiments, carried out in a single fracture at the Aespoe Hard Rock Laboratory (HRL) in Sweden, are identified by solving the inverse problem in a framework of the maximum likelihood theory. From the results, it is found that the parameter value uncertainty caused by a conceptual model of radionuclide migration is greater than that caused by a fluctuation in the observed breakthrough curve data. (author)

2005-10-03

110

The HARP experiment first physics results  

CERN Document Server

The HARP experiment at CERN is performing extensive measurements of hadron production cross sections and secondary particle yields, in the momentum range 1.5-15 GeV/c, over the full solid angle and using a large set of cryogenic and solid targets. First measurements of hadron production cross-sections in the forward region are reported using an aluminium target 5% of an interaction length thick and a proton beam of 12.9 GeV/c. A preliminary analysis in the large angle region of elastic scattering events produced with the cryogenic hydrogen target at 3 GeV/c beam momentum is also presented.

2005-01-01

111

The Doctorate in Counselor Education  

British Library Electronic Table of Contents (United Kingdom)

The doctorate in Counselor Education and Supervision is the terminal degree in the field of counselor education within the U.S. The authors surveyed CACREP-accredited doctoral programs to assess department characteristics, clinical experience and credentials, research experience, and the admission, retention, and evaluation of students. Results indicated that the PhD was a preferable degree to other degree offerings. Programs were found to be diverse in their policies and procedures relating to admissions and retention, time to complete the program, and student expectations. International students and faculty representation was found to be sparse in CACREP-doctoral programs. Implications for future research and practice are offered.

2011-01-01

112

The Baikal neutrino experiment  

International Nuclear Information System (INIS)

We review the status of the Lake Baikal Neutrino Experiment. Preparation towards a km"3-scale Gigaton Volume Detector (GVD) in Lake Baikal is currently a central activity. As an important milestone, a km"3-prototype string comprising of 12 optical modules and based on a completely new technology, has been installed and was put in operation together with NT200+ in April, 2009. We also present recent results from the long-term operation of NT200, including an improved limit on the diffuse astrophysical neutrino flux.

2011-01-11

113

Spin Duality on the Neutron (^3He)  

Energy Technology Data Exchange (ETDEWEB)

Thomas Jefferson National Accelerator Facility experiment E01-012 measured the 3He spin structure functions and virtual photon asymmetries in the resonance region in the momentum transfer range 1.0 < Q2 < 4.0 (GeV/c)2. Our date, when compared with existing deep inelastic scattering data, can be used to test quark-hadron duality in g1 and A1 for 3He and the neutron. Preliminary results for A{sub 1}{sup {sup 3}He} are presented, as well as some details about the experiment.

2007-02-01

114

Single event effects in the pixel readout chip for BTeV  

Energy Technology Data Exchange (ETDEWEB)

In future experiments the readout electronics for pixel detectors is required to be resistant to a very high radiation level. In this paper we report on irradiation tests performed on several preFPIX2 prototype pixel readout chips for the BTeV experiment exposed to a 200 MeV proton beam. The prototype chips have been implemented in commercial 0.25 {micro}m CMOS processes following radiation tolerant design rules. The results show that this ASIC design tolerates a large total radiation dose, and that radiation induced Single Event Effects occur at a manageable level.

2001-12-07

115

Reflected-shock initiation of explosives  

Energy Technology Data Exchange (ETDEWEB)

In a study of initiations caused by reflected shock from a high-impedance boundary, attempts to establish sufficient conditions for initiative are described. Shock polar analysis is used to discover the ranges of various flow regimes, general shock structures and pressure estimates of states behind the reflected wave. Using this knowledge, wave structure growth rates from hydrocode simulations are estimated and standard-shock initiation criteria are used; experiments are designed in which the initiation from a reflected-shock wave structure appears likely. Two experiments are described in which a reflected-shock wave from a uranium surface initiated PBX 9502. The experimental evidence is in good agreement with the assumptions and results of the analysis.

1993-08-01

116

Proceedings of the first analysis meeting on JUPITER-II Program  

Energy Technology Data Exchange (ETDEWEB)

The JUPITER-II Program is the Joint Physics Large Heterogeneous Core Critical Experiments Program between the U.S. Department of Energy (US DOE) and PNC, Japan. The experiments began in May 1982 and ended in April 1984, as a part of the ZPPR-13 program. The ZPPR-13 is a series of critical assemblies designed to study the fundamental neutronic behavior of large, radially-heterogeneous LMFBR cores. This report describes the results of analysis of ZPPR-13A and preliminary analysis of ZPPR-13B, and some topics of recent activities in fast reactor physics.

1984-12-31

117

Pressure drop and heat transfer in gas-cooled rod bundles  

International Nuclear Information System (INIS)

Extensive experimental and analytical investigations of fluid flow and heat transfer in gas-cooled rod bundles have been carried out. Different bundle geometries with partially or fully roughened rod surfaces were tested in a carbon dioxide loop. An advanced and comprehensive measuring control and instrumentation are important design features of this experiment. Comprehensive thermal hydraulic subchannel analysis computer codes have been developed in order to assist fuel element design calculation for gas-cooled reactors. The experiments, codes and their verification procedure are described and the results of comparisons between measured and calculated pressure and temperature distributions are given. (orig.).

118

Positron-Electron Pair Creation Near Threshold  

Science.gov (United States)

Positron-electron pair creation near the threshold energy is extremely difficult to investigate by both experiments and theory. First test experiments were performed at the ILL to determine the cross sections for positron-electron pair creation near threshold using prompt {gamma}-rays from different targets after neutron capture and conventional radioactive sources. Pair creation was studied in a Ge detector, which simultaneously acted as sample and detector. First results are presented which show a significant deviation from theoretical values near threshold.

2009-01-28

119

Plasma on a foundry cupola  

Science.gov (United States)

An experiment of a plasma torch on a production foundry cupola is reported. The test runs were conducted on a hot blast cupola, the blast temperature in the absence of plasma being 400 C. With the torch, the temperature of the blast was increased to 1000 C. The experiment was conducted for the manufacture of car engines with a 2.5 MW transportable plasma system. The cupola was boosted with a 4 MW torch and results included an increase in production of 45 percent, a decrease in coke rate and no more new iron in the loads. The plasma torch and hot air cupola furnace are described.

1991-01-01

120

IFA-2 collective ion accelerator experiments  

Energy Technology Data Exchange (ETDEWEB)

Ion acceleration has now been demonstrated with the IFA-2 collective ion accelerator system. The IFA-2 system is described, photoionization experiments are summarized, and ion results are presented. Using a 1 MeV electron beam and a 30 cm acceleration length, IFA-2 has produced 5 MeV H/sup +/, 10 MeV D/sup +/, and 20 MeV He/sup + +/. This means that accelerating fields of 33 MV/m over 30 cm have been achieved with a controlled collective accelerator for the first time.

1985-10-01

121

Electron combinational light scattering in disordered Ti_x_-_1Fe_x alloys: theory and experiment  

International Nuclear Information System (INIS)

Theoretical description of Raman scattering in disordered alloys of Ti and Zr with transition metals of groups 5-8 of the Mendeleev Periodic System in critical range of concentrations (CRC) is given. Results of Raman scattering experiment in the system Ti_1_-_xF_x at 0.0005

122

Elastic constants and volume changes associated with two high-pressure rhombohedral phase transformations in vanadium  

Energy Technology Data Exchange (ETDEWEB)

We present results from ab-initio electronic-structure calculations of mechanical properties of the rhombohedral phase of vanadium reported in recent experiments (R Ia), and other predicted high-pressure phases (R Ib and bcc), focusing on properties relevant to dynamic experiments. We find that of the three transitions the largest volume collapse (1.3%) is for the R Ia to R Ib transition. Calculations of the single crystal and polycrystal elastic constants reveal a remarkably small discontinuity across the phase transitions even at zero temperature where the transitions are first order.

2007-10-16

123

Demonstration experiment on improved radwaste evaporator  

Energy Technology Data Exchange (ETDEWEB)

High conductivity liquid waste, which is produced in nuclear power plants, is now processed with radwaste evaporator. The concentrated liquid waste in the evaporator is so highly radioactive and corrosive that the improvement on maintenability and reduction of exposure dose rate are desirable as well as high decontamination factor (DF). Fuji Electric constructed the improved experimental facility of evaporator and carried out an experiment to demonstrate DF, maintenability and controllability of system. As the results, DF, maintenability and controllability were proved to be excellent and its applicability to nuclear power plant was well established.

1988-07-01

124

Daya Bay Neutrino Experiment: Goal, Progress and Schedule  

CERN Document Server

Daya Bay Neutrino Experiment is dedicated to measuring the last unobserved neutrino mixing angle theta_13. The predicted precision on sin^2(2theta_13) is 0.01 at 90% confidence level. This document briefly reviews the measurement method and detector construction status. The first two anti-neutrino detectors' dry run result is also discussed. The Daya Bay near hall data taking is expected to commence in the summer of 2011 and the data taking of all of the three halls in the summer of 2012.

2011-01-01

125

DECOVALEX - Mathematical models of coupled T-H-M processes for nuclear waste repositories. Executive summary for Phases I,II and III  

Energy Technology Data Exchange (ETDEWEB)

This executive summary presents the motivation, structure, objectives, methodologies and results of the first stage of the international DECOVALEX project - DECOVALEX I (1992-1995). The acronym stands for Development of Coupled Models and their Validation against Experiment in Nuclear Waste Isolation, and the project is an international effort to develop mathematical models, numerical methods and computer codes for coupled thermo-hydro-mechanical processes in fractured rocks and buffer materials for geological isolation of spent nuclear fuel and other radioactive wastes, and validate them against laboratory and field experiments. 24 refs.

1996-06-01

126

Biosorption process for removing heavy metal ions using water milfoil (Myriophyllum Spicatum) in contaminated water  

Energy Technology Data Exchange (ETDEWEB)

A small scale biomass metal contacting experiment was performed to screen the optimal plant species for biosorption and bioaccumulation of cadmium, zinc, nickel, lead, and copper. Experiments were also conducted to test the ability of the biomass to lower the metal concentrations below the US Environmental Protection Agency surface water discharge criteria. The minimum residual concentration was 0.1 mg/L for zinc, 0.004 mg/L for lead, and about 0.01 mg/L for cadmium, nickel, and lead. Results indicate that water milfoil can be used for bioremoval of metals.

1995-12-31

127

Assessment of RELAP5/MOD2 against a natural circulation experiment in Nuclear Power Plant Borssele. International Agreement Report  

Energy Technology Data Exchange (ETDEWEB)

As part of the ICAP (International Code Assessment and Applications Program) agreement between ECN (Netherlands Energy Research Foundation) and USNRC, ECN has performed a number of assessment calculations for the thermohydraulic system analysis code RELAP5/MOD2/36.05. This document describes the assessment of this computer program versus a natural circulation experiment as conducted at the Borssele Nuclear Power Plant. The results of this comparison show that the code RELAP5/MOD2 predicts well the natural circulation behaviour of Nuclear Power Plant Borssele.

1993-07-01

128

American National Standard ANSI/ANS-8.6: Safety in conducting subcritical neutron-multiplication measurements {open_quote}In Situ{close_quote}  

Energy Technology Data Exchange (ETDEWEB)

Safe and economical operations with fissile materials require knowledge of the subcriticality of configurations that arise in material processing, storage, and transportation. Data from critical experiments have been a principal source of information with which to establish safety margins. However, the lower cost and the expediency of performing confirmatory subcritical measurements on the process floor or in the storage vault resulted in much of the early criticality safety guidance being based on subcritical in situ experiments.

1996-10-01

129

Initial results of the CD-1 reliable multicast experiment  

Energy Technology Data Exchange (ETDEWEB)

During the past year, an experiment has been underway to test use of reliable multicast capabilities for transmission of continuous data in the Global Communication Infrastructure. For the experiment a version of the CD-1 protocol was multicast enabled. The experiment has demonstrated the feasibility of transmitting data in a multicast mode over the GCI. In the case of the Comprehensive Nuclear Test-Ban Treaty the sender could be the station and the receivers the International Data Center (IDC) and one or more National Data Centers (NDC). The potential advantages of multicasting include (a) the timely receipt of the data by the IDC and the host NDC and (b) the simultaneous availability of the raw station data at, at least, two locations. The latter, by introducing redundant data paths, decreases the probability of loss of station data due to a potential failure of a single data receiver. This experiment ...

2000-09-29

130

Simulation of natural convection cooling phenomena for research reactors using the code PARET  

International Nuclear Information System (INIS)

This study deals with testing the capability of the code PARET to simulate natural convection cooling phenomena under different boundary conditions. In addition to applying and testing some new options related to simulation of the control rod movement and studying the reactivity effect of thermal expansion fuel elements. The experiments of the simple thermal hydraulic loop of Missouri university about natural cooling phenomena in two narrow paralled channels were used to validate the code. The study indicate good results regarding the distribution of coolant flux velocity and clad temperature. In particular the heat transfer coefficient of natural convection has been calculated in good agreement with the experiment. On the other hand, the core of MNSR reactor has been modelled to simulate the reactor dynamic behaviour under natural convection cooling conditions for different initial power level. The observed oscillation ...

131

Simulation of natural convection cooling phenomena for research reactors using the code PARET  

International Nuclear Information System (INIS)

This study deals with testing the capacity of the code PARET to simulate natural circulation phenomena under different boundary conditions in addition to assessment of some new options related to simulation of control rod movement and the reactivity effect of thermal expansion fuel elements. the experiments of the simple thermal hydraulic loop of Missouri University about natural circulation phenomena in narrow parallel channel were used to validate the code. The results indicate good agreements regarding the evolution of coolant velocity and clad temperature. In particular the heat transfer coefficient of natural convection has been calculated in good agreement with the experiment. On the other hand, the core of MNSR reactor has been modelled to stimulate the reactor dynamic behaviour under natural circulation condition for different initial power level. The observed oscillations during the initial phase vanish gradually ...

132

Benchmark Analysis of Subcritical Noise Measurements on a Nickel-Reflected Plutonium Metal Sphere  

Energy Technology Data Exchange (ETDEWEB)

Subcritical experiments using californium source-driven noise analysis (CSDNA) and Feynman variance-to-mean methods were performed with an alpha-phase plutonium sphere reflected by nickel shells, up to a maximum thickness of 7.62 cm. Both methods provide means of determining the subcritical multiplication of a system containing nuclear material. A benchmark analysis of the experiments was performed for inclusion in the 2010 edition of the International Handbook of Evaluated Criticality Safety Benchmark Experiments. Benchmark models have been developed that represent these subcritical experiments. An analysis of the computed eigenvalues and the uncertainty in the experiment and methods was performed. The eigenvalues computed using the CSDNA method were very close to those calculated using MCNP5; however, computed eigenvalues are used in the analysis of the CSDNA method. Independent ...

2009-09-01

133

Time-domain dynamic opto-rheology study of polymer films using step-scan FTIR time-resolved spectroscopy (S{sup 2}FTIR TRS)  

Energy Technology Data Exchange (ETDEWEB)

Step-scan Fourier transform infrared spectroscopy in conjunction with impulse stress on polymer films has been used to monitor dynamic rheological responses in real time. A novel piezo-electrically-driven polymer microrheometer was employed to apply repetitive impulses to the polymer sample while time-domain spectra were recorded. Recent results include the study of both semi-crystalline polymers such as isotactic polypropylene (iPP) and elastomers such as Estane polyester/polyurethane copolymer and Kraton tri-block copolymer. The spectral changes of iPP are consistent with frequency-domain results. For iPP at room temperature, large differences in the response times of different absorption bands are not seen. However, the orientation response of the CH{sub 3} rocking mode is slightly slower than the responses of the backbone modes. To the authors` knowledge, this is the first reported successful step-scan FTIR time-domain dynamic polymer ...

1998-07-01

134

The cosmic-ray antiproton spectrum between 0. 1 and 1. 5 GeV kinetic energy  

Energy Technology Data Exchange (ETDEWEB)

In the summer of 1980, a balloon-borne cosmic ray experiment reported the detection of 14 low energy antiprotons during an 18 hour flight. This measurement represented an antiproton intensity two orders of magnitude greater than that predicted by conventional theories. This surprising result triggered a flurry of papers theorizing the origin of these particles, including the prediction of domains of primary antimatter, and evidence for supersymmetric particle annihilation. Not until the summer of 1987 was a follow up experiment (PBAR) performed. The PBAR detector has both better resolution and a larger dynamic range in energy than the previous detector. It measured the energy spectrum of antiprotons in the 0.1-1.5 GeV kinetic energy range. The present work describes the instrument, the experiment, and the results. Our analysis of the PBAR data reveals no antiprotons in the energy ...

1988-01-01

135

Structure of molten alkali halides  

Energy Technology Data Exchange (ETDEWEB)

The results of X-ray and neutron diffraction experiments on molten alkali halides in which some data of our experiments by X-ray diffraction such as those of molten LiCl, NaCl, KCl, LiBr and KBr are included were summarized. The first peak positions in the radial distribution function in molten alkali halides by X-ray or neutron diffraction experiments are always longer than those by computer simulations and the differences of 0.1 -- 0.3 A exceed the experimental error. It seems to be due to the deformation of the electron shell. In the computer simulation, the shell model which has the spherical deformation was expected to have a closer value of the first peak position to the experimental one than the rigid ion model by taking the polarization of ions. However, no change in the first peak position was found. Therefore, the non-spherical deformation of electron shell at the point where ions are in ...

1982-06-01

136

Structure of molten alkali halides  

International Nuclear Information System (INIS)

The results of X-ray and neutron diffraction experiments on molten alkali halides in which some data of our experiments by X-ray diffraction such as those of molten LiCl, NaCl, KCl, LiBr and KBr are included were summarized. The first peak positions in the radial distribution function in molten alkali halides by X-ray or neutron diffraction experiments are always longer than those by computer simulations and the differences of 0.1 -- 0.3 A exceed the experimental error. It seems to be due to the deformation of the electron shell. In the computer simulation, the shell model which has the spherical deformation was expected to have more closer value of the first peak position to the experimental one than the rigid ion model by taking the polarization of ions. However, no change in the first peak position was found. Therefore, the non-spherical deformation of electron shell at the point where ions are in ...

1982-01-01

137

Removal of iodine species by concentrated nitric acid, (2)  

International Nuclear Information System (INIS)

One of the most effective removing processes of iodine species is what is called ''Iodox Process'', which contains oxidation and absorption of iodine species by highly concentrated nitric acid. The result of fundamental test with bubble column in this process had been reported. Present paper describes the fundamental experiment by the use of packed column. This experiment has been carried out to clear the effect of feed gas flow rate, nitric acid flow rate, nitric acid concentration, and methyl iodide concentration on removal efficiency of methyl iodide. The following results were obtained. The decontamination factor of methyl iodide (DF) increases exponentially with nitric acid concentration, which agrees with the result obtained by using the bubble column. The factor is in inverse proportion to feed gas flow rate, and is also almost independent of nitric acid flow rate and methyl ...

1978-07-01

138

Mott-Schwinger Scattering of Polarized Low Energy Neutrons up to Thermal Energies  

Energy Technology Data Exchange (ETDEWEB)

The availability of new, high-intensity, cold and thermal neutron sources has opened the possibility of performing high-precision fundamental neutron physics experiments, including measurements that study the hadronic weak interaction and standard model test measurements, using neutron decay. The observables in these experiments are usually correlated with the direction of neutron polarization and are often very small (10 8 10 6). Mott-Schwinger scattering of polarized neutrons can produce spin-dependent shifts in beam centroids, which has the potential to produce significant systematic effects for these types of experiments. An accurate calculation of this process for neutral atoms and basic molecules has not been carried out for low neutron energies. In this work, we derive a general expression for the electromagnetic (Mott-Schwinger) contributions to the analyzing power for low-energy neutron scattering. We obtain ...

2008-10-01

139

Effects of a chelating resin on metal bioavailability and toxicity to estuarine invertebrates: Divergent results of field and laboratory tests  

International Nuclear Information System (INIS)

Benthic invertebrates can uptake metals through diffusion of free ion solutes, or ingestion of sediment-bound forms. This study investigated the efficacy of the metal chelating resin SIR 300TM in adsorbing porewater metals and isolating pathways of metal exposure. A field experiment (Botany Bay, Sydney, Australia) and a laboratory toxicity test each manipulated the availability of porewater metals within contaminated and uncontaminated sediments. It was predicted that within contaminated sediments, the resin would adsorb porewater metals and reduce toxicity to invertebrates, but in uncontaminated sediments, the resin would not significantly affect these variables. Whereas in the laboratory, the resin produced the predicted results, in the field the resin increased porewater metal concentrations of contaminated sediments for at least 34 days and decreased abundances of four macroinvertebrate groups, and richness in all sediments. These ...

2010-05-01

140

A study on the treatment of radioactive liquid wastes using synthetic by air intake system  

International Nuclear Information System (INIS)

In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste ...

2003-11-27

141

Thermodynamic Model of Aluminum Combustion in SDF Explosions  

Energy Technology Data Exchange (ETDEWEB)

Thermodynamic states encountered during combustion of Aluminum powder in Shock-Dispersed-Fuel (SDF) explosions were analyzed with the Cheetah code. Results are displayed in the Le Chatelier diagram: the locus of states of specific internal energy versus temperature. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f(T) suitable for specifying the thermodynamic properties required for gas-dynamic models of combustion in explosions.

2006-06-19

142

The natural convection cooling with vaporizing deuterium for the horizontally arranged cold neutron source of the HFR - Grenoble  

International Nuclear Information System (INIS)

Natural convection of vaporizing Deuterium at 25 K transports the heat generated in the moderator cell of the cold neutron source to a He cooled condenser. The thermohydraulics of this thermosiphon were precalculated and the results verified by experiments in a 1:1 model using D_2 as fluid. The experimental results show that the thermosiphon operates stable. The demanded liquid content of the cell as well as wall temperatures below 50 K can be ensured by a proper design of the cell outlet flow geometry. A 7 min. loss of cryogenic power results in transient temperatures of the cell wall of not more than 300 K.

1991-08-01

143

Results from field experiments on AC polluted insulators in Mexico  

Energy Technology Data Exchange (ETDEWEB)

As contamination flashover is in Mexico the second cause of transmission line faults, the Mexican Electrical Research Institute carried out a project to determine pollution patterns for the Republic of Mexico to be used for the design of external insulation. Results from the project are presented: the modelling, based on the field data of 23 experimental sites, of long term variations of pollution patterns as a function of environmental variables, insulator shape and position, as well as other important field results. 32 refs, 2 figs, 4 tabs

1995-12-01

144

Investigations for obtaining enhanced SHG element of KH_2PO_4 crystal  

International Nuclear Information System (INIS)

We report investigations of enhancement in material conversion efficiency of KDP for SHG applications. The limitation of conventional technique of growing KDP crystal was overcome in the present work by adopting a growth method to grow KDP directly in type-II phase matching direction. The conventional technique results in #approx#30% of the crystal volume usable for SHG applications whereas the present method has resulted in enhancing it to #approx#90%. The orientation of the element was confirmed by frequency conversion experiment using Nd:YAG laser. The UV-vis transmittance obtained was 92%. The interferometric results show that the crystals have excellent optical homogeneity.

2010-04-01

145

ORALLOY (93.15 235U) METAL ANNULI WITH BERYLLIUM CORE  

International Nuclear Information System (INIS)

A variety of critical experiments were constructed of enriched uranium metal during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, two were performed that consisted of uranium metal annuli with a solid beryllium metal core. The outer diameter of the annuli was approximately 13 or 15 inches with an inner diameter of ...

146

Tunneling spectra of high-temperature superconductors  

International Nuclear Information System (INIS)

The frequency dependence of the tunneling spectrum #alpha#"2F (#omega#) is analyzed in terms of electron pairing induced by exchange of acoustic plasmons in addition to the usual phonon-exchange mechanism. Analytic expressions are obtained for the electron self-energy, the tunneling function #alpha#"2F, and the electron pairing coupling lambda which determines the superconducting properties. The resulting theory is applied to recent tunneling data of Nb_3Sn in order to examine the anomalous discrepancies with the phonon density of states found by neutron scattering experiments. The results demonstrate how the high-temperature (T/sub c/ approx. 20 "0K) superconducting properties of A-15 compounds are enhanced by acoustic-plasmon contributions, and thus they reconcile these high transition temperatures with the relatively small values of the phonon part of lambda estimated from several independent ...

147

The microscopic dynamics of condensed parahydrogen  

Energy Technology Data Exchange (ETDEWEB)

We have measured the almost-pure incoherent scattering function of liquid and solid parahydrogen, using inelastic neutron scattering. The experiments were carried out on TOSCA, a time-of-flight, inverse-geometry, crystal-analyzer spectrometer, operating on the pulsed neutron source at ISIS (UK). The experiments have been planned taking advantage of the intrinsic incoherence introduced in the scattering process by the rotational transitions. The measured double-differential cross section gives a direct experimental access to the microscopic dynamics of condensed hydrogen. From the high-energy region of the spectrum, where the impulse approximation for the center of mass motion applies, we have been able to extract the translational mean kinetic energy. In the low-energy region, using the Gaussian approximation, we compare the experimental data in the liquid phase with the results of a model for the velocity autocorrelation ...

2002-07-01

148

Study on the characterization of the neutron radiography facility in HANARO for two-phase flow research  

Energy Technology Data Exchange (ETDEWEB)

For the application of dynamic neutron radiography to the two-phase flow research using HANARO, several experimental items to which the radiography technique is beneficial were identified through the review of the outputs from the related researches and the discussions with experts. Also, the investigation of the equipments including the beam port, camera and converter was made and a hardware and a software for image processing were equipped. It was confirmed that the calibration curve for the attenuation of neutron beam in fluid which is required for the two-phase flow experiment could be obtained by the computer code calculation. Based on the investigation results on the equipment and the results from the measurement of BNCT beam characteristics, a high speed camera and an image intensifier will be purchased. Then, the high speed dynamic neutron radiography facility for two-phase flow experiments will ...

2001-01-01

149

Spectrograph for free-electron laser experiments  

International Nuclear Information System (INIS)

The design and construction of a Browne-Buechner type round pole face magnetic electron spectrograph is described. The design is based on the first order transfer properties of the bending magnet including the focal surface, dispersion, magnification and resolution. Second order aberrations are compared wit numerical ray tracing results using measured field data to simulate the magnet. The numerical results are also compared with floating wire measurements on the system. Agreement is within one part in 10"4. Data extraction from the instrument is done with an array of copper detectors placed along the focal surface. The spectrograph has been successfully employed in free-electron laser (FEL) experiments for over a year.

1983-03-21

150

RF conditioned dc discharges for excitation of rare gas halide lasers. Final report  

Energy Technology Data Exchange (ETDEWEB)

Results of experiments performed utilizing high-power microwave sources for laser-discharge switching and preionization are reported. These results are not definitive, but are promising. Significant preionization using microwaves is possible. Some ability to switch the discharge and operate a laser have been demonstrated. More work needs to be performed to perfect the microwave coupling to the laser mixture. In particular, experiments with the microwaves better concentrated between the electrodes should be performed. The best way to accomplish this appears to be using the side-feed geometry; however, a large expansion of the microwaves should occur (to well below the power able to break down the window), and then a cylindrical lens should be used to focus the microwaves between the electrodes. 2 references.

1983-01-01

151

Pencil-like mm-size electron beams produced with linear inductive voltage adders  

International Nuclear Information System (INIS)

We present the design, analysis, and results of the high brightness electron beam experiments currently under investigation at Sandia National Laboratories. The anticipated beam parameters are the following: energy 12 MeV, current 35 endash 40 kA, rms radius 0.5 mm, and pulse duration 40 ns full width at half-maximum. The accelerator is SABRE, a pulsed linear inductive voltage adder modified to higher impedance, and the electron source is a magnetically immersed foilless electron diode. 20 endash 30 T solenoidal magnets are required to insulate the diode and contain the beam to its extremely small-sized (1 mm) envelope. These experiments are designed to push the technology to produce the highest possible electron current in a submillimeter radius beam. Design, numerical simulations, and experimental results are presented. copyright 1997 American Institute of Physics.

152

Neutron-induced fission cross-section of {sup 233}U in the energy range 0.5<E{sub n}< 20 MeV  

Energy Technology Data Exchange (ETDEWEB)

The neutron-induced fission cross-section of {sup 233}U has been measured at the CERN n-TOF facility relative to the standard fission cross-section of {sup 235}U between 0.5 and 20MeV. The experiment was performed with a fast ionization chamber for the detection of the fission fragments and to discriminate against {alpha} -particles from the natural radioactivity of the samples. The high instantaneous flux and the low background of the n-TOF facility result in data with uncertainties of {approx} 3%, which were found in good agreement with previous experiments. The high quality of the present results allows to improve the evaluation of the {sup 233}U (n,f) cross-section and, consequently, the design of energy systems based on the Th/U cycle. (orig.)

2011-01-15

153

Multi-GeV electron spectrometer  

Energy Technology Data Exchange (ETDEWEB)

The advance in laser-plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular the upcoming experiments with the FLAME laser at LNF will enter the GeV regime with almost 1nC of electrons. From the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need to develop a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV) under still unknown angular divergences. Within the PlasmonX experiment at LNF a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence present unprecedented ...

2010-11-11

154

Computer simulation of explosive fracture of oil shale  

Energy Technology Data Exchange (ETDEWEB)

The steps in assembling the computational tools needed to simulate the explosive fracture of oil shale have been described. The resulting code, with its input data, then was used to simulate 3 explosive field experiments. The results of the calculations are in good agreement with what actually occurred in the field. Further detailed comparisons are in progress for these experiments and the others that have been conducted. The development of computer codes as tools to predict rock breakage makes a variety of studies possible. The properties of the explosive can be changed to see how the extent of rubbling is affected. Studies of spacing and delays for decked charges also are possible. The codes can be applied in situations, such as confined-volume blasting, at the frontiers of blasting technology. These areas are vital to the effective utilization of oil shale resources, especially with in situ ...

1981-01-01

155

Bumper zone at the Aldermac mine tailing site : study of certain remediation techniques; Zones d'epanchement du parc a residus miniers Aldermac : etude de certaines techniques de rehabilitation  

Energy Technology Data Exchange (ETDEWEB)

Acid mine drainage is probably the most important problem facing the mining industry. In this study, the authors evaluated different techniques for the remediation of mine tailings. An in situ characterization of the Aldermac mine tailings was conducted and the results were presented in this poster presentation. The site characterization was performed to determine the extent of the contamination, and sampling of soils was also performed for laboratory experiments in soil covers. The authors described the methodology followed in the laboratory experiments. Chemical analysis of the leaching water was performed to determine its composition in metals. Microbiological analysis was also conducted, as well as the determination of the water saturation index. The authors indicated that they will analyze the results further. tabs., 12 figs.

2000-07-01

156

Behaviour of silicon released during alteration of nuclear waste glass in compacted clay  

Energy Technology Data Exchange (ETDEWEB)

Long term integrated in situ experiments are performed in the HADES underground research facility (Mol, Belgium) in order to study the coupled reactivity between the different components of an underground repository for vitrified high level radioactive waste (HLW): glass, compacted clay, and stainless steel containers, at 90 degrees C and under gamma irradiation. Studies pertaining to the behaviour of silicon, a major element released during glass alteration, are presented here. Data collected from the integrated experiment, from simplified tests, and from modelling are put together, giving complementary information. The integrated experiment is used to investigate overall reactivity, whereas diffusion experiments coupled with modelling focused on the precipitation of silica in clay media. In the integrated in situ experiment, a bentonite clay (FoCa7) mixed with 5 wt.% of powdered ...

2007-02-15

157

Results of two-phase natural circulation in hot-leg U-bend simulation experiments  

Energy Technology Data Exchange (ETDEWEB)

In order to study the two-phase natural circulation and flow termination during a small break loss of coolant accident in LWR, simulation experiments have been performed using two different thermal-hydraulic loops. The main focus of the experiment was the two-phase flow behavior in the hot-leg U-bend typical of BandW LWR systems. The first group of experiments was carried out in the nitrogen gas-water adiabatic simulation loop and the second in the Freon 113 boiling and condensation loop. Both of the loops have been designed as a flow visualization facility and built according to the two-phase flow scaling criteria developed under this program. The nitrogen gas-water system has been used to isolate key hydrodynamic phenomena such as the phase distribution, relative velocity between phases, two-phase flow regimes and flow termination mechanisms, whereas the Freon loop has been used to study the effect of fluid properties, ...

1987-01-01

158

Remediation of contaminated agricultural soils near a former Pb/Zn smelter in Austria: Batch, pot and field experiments  

International Nuclear Information System (INIS)

Metal contaminated crops from contaminated soils are possible hazards for the food chain. The aim of this study was to find practical and cost-effective measures to reduce metal uptake in crops grown on metal contaminated soils near a former metal smelter in Austria. Metal-inefficient cultivars of crop plants commonly grown in the area were investigated in combination with in-situ soil amendments. A laboratory batch experiment using 15 potential amendments was used to select 5 amendments to treat contaminated soil in a pot study using two Barley (Hordeum vulgare L.) cultivars that differed in their ability to accumulate cadmium. Results from this experiment identified 3 of these amendments for use in a field trial. In the pot experiment a reduction in ammonium nitrate extractable Cd (<41%) and Pb (<49%) compared to the controls was measured, with a concurrent reduction of uptake into barley grain ...

2006-11-01

159

Measurement of the concentration of coal slurry using microwave techniques; Maikuroha wo oyoshita konodo sekitan slurry no nodo sokutei ni tsuite  

Energy Technology Data Exchange (ETDEWEB)

The paper reported on an experiment on measurement of concentration of highly concentrated coal slurry using microwaves carried out at Miike coal preparation works. The purpose of the experiment was to investigate applicability of microwave moisture content measurement of slurry of a mixture of coal and coal particles and to use it to the control of process such as coal preparation and processing. In the experiment, a method for measuring the slurry concentration was adopted in which the container filled with highly concentrated coal slurry was irradiated with microwaves and the damping of strength of the penetrating microwaves was detected. As a result of the experiment, it was found out that there was a big correlation between the capacitive concentration of slurry and the damping ratio of microwaves. When irradiating slurry with microwaves of 1GHz frequency, a big correlation ...

1996-09-30

160

Free electron laser experiments using a long pulse induction linac  

International Nuclear Information System (INIS)

The NRL Long Pulse Induction Linac is being employed in a Free Electron Laser (FEL) experiment. The authors present results of beam transport and focusing experiments as well as measurements of the output radiation generated by various magnetic wigglers. The electron gun of the accelerator presently has a 17-cmdiam. cold cathode which is located in a nearly zero magnetic field (B /SUB z/ less than or equal to 5 G). The gun voltage is flat to within approx. = + or - 5% for 1.5 #mu#sec with this graphite brush cathode. The beam is focused by a series of solenoidal coils as it propagates through the 4-m-long accelerator."2 A solenoidal field which can be varied from 1-10 kG confines the beam in the FEL interaction region. Previous experiments were limited by poor beam transport, focusing, and matching into the relatively large solenoidal field in the FEL region. By smoothing the axial magnetic field ...

161

Environmental status of Technical Area 49, Los Alamos, New Mexico  

Energy Technology Data Exchange (ETDEWEB)

A series of experiments involving high explosives and radioactive materials were conducted at Los Alamos, New Mexico, primarily to understand certain safety aspects of operational nuclear weapons. The experiments were conducted underground in large diameter holes as deep as 120 ft. The location was selected because it had geologic and hydrologic characteristics that assured complete containment of the experiments and precluded any possible contamination of groundwater. Important features verified by the USGS included the absence of any recharge and about 1200 feet of dry rock above the groundwater aquifer. Residual materials dispersed by detonation of the high explosives remain at the bottom of the experimental holes. The materials of significance from an environmental standpoint include about 40 kg of plutonium, 93 kg of enriched uranium, at least 82 kg of depleted uranium, 13 kg of beryllium, and an undetermined amount of ...

1987-11-01

162

The transfer of trichloroethylene (TCE) from a shower to indoor air: Experimental measurements and their implications  

Energy Technology Data Exchange (ETDEWEB)

Experiments were performed to measure the transfer of trichloroethylene (TCE), a volatile organic compound (VOC), from tap water in showers to indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between influent and effluent concentrations.We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 51 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there is no statistically significant difference between ...

1991-08-01

163

Review of fires and fire control methods for nuclear air cleaning systems  

International Nuclear Information System (INIS)

The nuclear power industry has experienced four carbon based adsorbent fires in its history, one was of the Monticello Standby Gas Treatment System and other three were in various off-gas delay beds. Although, some of the latter may not be classified as a full fledged fires. There were a number of experiments performed relating to igniting carbon beds and experiments relating to attempts at extinguishing set fires reported in the literature. Review of these experiments indicates that fire resulting from decay heat of adsorbed radioactive iodine is not justified even under the somewhat unrealistic source terms still in effect. At the same time the non-nuclear chemical industry application of carbon base adsorbents for solvent recovery has resulted in numerous fires and significant property losses. Fire control systems installed in nuclear air cleaning systems in the US consists of ...

1987-05-01

164

Radionuclide adsorption characteristics around coastal water  

Energy Technology Data Exchange (ETDEWEB)

The adsorption capacity of radionuclides onto suspended sediment was experimented on each of the coastal seawater sampled around the Kori and the Wolsung nuclear power plant. During the experiment the quantity and size fraction of suspended sediment were adjusted and the seawater and sediment chemistry is approximated to the expected field condition. Because the sorption capacity depends on the specific minerals, ocean chemistry and radionuclide involved, it is necessary to analyze sediment mineralogy. Clay mineral is dominant in seabed mineral and suspended sediment as the result of x-ray diffraction. Radionuclide sorbed to silty-clay mineral can be rather transported to ocean than scavenged to seabed because of low quantity and fine grained suspended sediment in the coast around the Kori and the Wolsung. The result of adsorption examinations shows that {sup 139}Ce and {sup 51}Cr and {sup 110m}Ag are ...

1999-07-01

165

Radionuclide adsorption characteristics around coastal water  

International Nuclear Information System (INIS)

The adsorption capacity of radionuclides onto suspended sediment was experimented on each of the coastal seawater sampled around the Kori and the Wolsung nuclear power plant. During the experiment the quantity and size fraction of suspended sediment were adjusted and the seawater and sediment chemistry is approximated to the expected field condition. Because the sorption capacity depends on the specific minerals, ocean chemistry and radionuclide involved, it is necessary to analyze sediment mineralogy. Clay mineral is dominant in seabed mineral and suspended sediment as the result of x-ray diffraction. Radionuclide sorbed to silty-clay mineral can be rather transported to ocean than scavenged to seabed because of low quantity and fine grained suspended sediment in the coast around the Kori and the Wolsung. The result of adsorption examinations shows that "1"3"9Ce and "5"1Cr and "1"1"0"mAg are strongly ...

1999-11-04

166

Irradiation-effects considerations for the SP-100 space reactor  

International Nuclear Information System (INIS)

The Sp-100 reactor is a lithium-cooled high-temperature fast-spectrum reactor. The fuel is UN. The cladding is fabricated from PWC-11, a Nb alloy, as are all the primary structural components. A reactor lifetime of up to ten years with an operating temperature of 1370 K is required. The accumulated fluence is expected to be 6 x10"2"2 n/cm"2. The damage, which could result in swelling or embrittlement, anneals out as fast as it occurs for the majority of the structure. This has been confirmed by earlier radiation testing. A number of components, however, are exposed to lower temperatures and the reactor design and materials selection for these components must take this into consideration. Radiation effects must also be considered for the UN fuel, bearing materials, etc. To data an instrumented experiment, MOTO 1000A, has been conducted in the FFTF reactor and as uninstrumented experiment SPM-1 in the EBR-II reactor. In this ...

1992-03-01

167

Good practice and successful experience of cooperation at Daya Bay and Ling Ao  

International Nuclear Information System (INIS)

Electricite de France, (EDF) in the late sixties and China through 10. 5-year Plan adopted the same approach of standardized NPPs to benefit from the series effect and to increase and speed up self reliance and localization. This approach also allows to continuously gather the feedback from design, construction and operation and to use it to constantly improve future and present nuclear power plants, by optimizing design features, construction phase and generation performances for safety, quality, cost and schedule aspects. Daya Bay NPP put into commercial operation in 1994 is posting high level safety and operation results. At Ling Ao NPP Chinese engineers of LANPC, with the contribution of the Chinese industry, have efficiency and successfully managed engineering, construction and operation preparation. GNPJVC / LANPC and EDF are developing permanent and mutual experience feedback exchanges in all areas of engineering, maintenance and ...

168

Forecasting neutrino masses from combining KATRIN and the CMB: Frequentist and Bayesian analyses  

CERN Document Server

We present a showcase for deriving bounds on the neutrino masses from laboratory experiments and cosmological observations. We compare the frequentist and Bayesian bounds on the effective electron neutrino mass m_beta which the KATRIN neutrino mass experiment is expected to obtain, using both an analytical likelihood function and Monte Carlo simulations of KATRIN. Assuming a uniform prior in m_beta, we find that a null result yields an upper bound of about 0.17 eV at 90% confidence in the Bayesian analysis, to be compared with the frequentist KATRIN reference value of 0.20 eV. This is a significant difference when judged relative to the systematic and statistical uncertainties of the experiment. On the other hand, an input m_beta=0.35 eV, which is the KATRIN 5sigma detection threshold, would be detected at virtually the same level. Finally, we combine the simulated KATRIN results ...

2007-01-01

169

Comparisons of two-phase microgravity calculations using current and new flow regime maps in RELAP5  

Energy Technology Data Exchange (ETDEWEB)

Recently, many experiments designed to quantify the parameters involved in microgravity two-phase flow have been performed. These experiments give significant insight to the differences between the flow regimes in 1-g and microgravity. However, the new correlations for pressure drop, heat transfer, and the flow regime maps are yet to be implemented into analytical methods. The purpose of this study is to model a KC-135 microgravity experiment, using the thermal-hydraulic does RELAP5/MOD2 and ATHENA. A comparison of these experimental results to code calculations from RELAP5/MOD2 and ATHENA is shown. Results show little difference between the ATHENA and the RELAP5 calculations. Also, modifications are made to the two-phase flow regime map in RELAP5 to model microgravity predictions. There is a substantial difference between the code's calculation before and after the changes ...

1988-01-01

170

Comparisons of two-phase microgravity calculations using current and new flow regime maps in RELAP5  

International Nuclear Information System (INIS)

Recently, many experiments designed to quantify the parameters involved in microgravity two-phase flow have been performed. These experiments give significant insight to the differences between the flow regimes in 1-g and microgravity. However, the new correlations for pressure drop, heat transfer, and the flow regime maps are yet to be implemented into analytical methods. The purpose of this study is to model a KC-135 microgravity experiment, using the thermal-hydraulic does RELAP5/MOD2 and ATHENA. A comparison of these experimental results to code calculations from RELAP5/MOD2 and ATHENA is shown. Results show little difference between the ATHENA and the RELAP5 calculations. Also, modifications are made to the two-phase flow regime map in RELAP5 to model microgravity predictions. There is a substantial difference between the code's calculation before and after the changes were ...

1988-11-04

171

Cluster Analysis of Gene Expression Data  

CERN Document Server

The expression levels of many thousands of genes can be measured simultaneously by DNA microarrays (chips). This novel experimental tool has revolutionized research in molecular biology and generated considerable excitement. A typical experiment uses a few tens of such chips, each dedicated to a single sample - such as tissue extracted from a particular tumor. The results of such an experiment contain several hundred thousand numbers, that come in the form of a table, of several thousand rows (one for each gene) and 50 - 100 columns (one for each sample). We developed a clustering methodology to mine such data. In this review I provide a very basic introduction to the subject, aimed at a physics audience with no prior knowledge of either gene expression or clustering methods. I explain what genes are, what is gene expression and how it is measured by DNA chips. Next I explain what is meant by "clustering" and how we analyze ...

2002-01-01

173

Busted Butte : final report on laboratory radionuclide migration experiments in non-welded tuff under unsaturated and saturated conditions  

International Nuclear Information System (INIS)

Three blocks of non-welded tuff, one nominally one cubic foot (trial block) in volume and the other two, nominally one cubic meter (1 m3) in volume, were excavated from the Busted Butte Test Facility on the Nevada Test Site in 1999 and transported to the Atomic Energy of Canada Limited Whiteshell Laboratories in Pinawa, Manitoba. The trial block and one of the 1-m3 blocks were used for radionuclide migration experiments under unsaturated conditions; the remaining 1-m3 block was used for similar migration experiments under saturated conditions. After a vertical flow of synthetic transport solution was set up under unsaturated conditions, a suite of conservative and chemically reactive radionuclide tracers was injected at volumetric flow rates of 20 mL/hr in the trial block, and 10 mL/hr in two locations on the upper surface of the 1-m3 block. These flow rates correspond to infiltration rates of about 120 cm/year and about 17 cm/year, ...

2005-09-13

174

FY1999 Meeting of The Society of Heating, Air-Conditioning and Sanitary Engineering of Japan. Thermal simulation I; 1999 nendo gakujutsu koenkai gaiyo. Onnetsu simulation 1  

Energy Technology Data Exchange (ETDEWEB)

E-35 reported the specific air flow analysis program using a CFSV model (including a human body model) to develop a high-accuracy evaluation simulator for heterogeneous thermal environment based on human thermal physiological conditions. E-36 reported development of the radiation heat transfer analysis module by using a numerical integral method to calculate shape factors. Radiation heat transfer characteristics every body part were clarified quantitatively by this module. E-37 reported the results on continuous measurement of physiological conditions and thermal environment factors every monitor under controlled indoor thermal environment, to collect measurement data necessary for improving the accuracy of a prediction program for human body temperatures. E-38 reported the study result on physiological reaction and subjective evaluation through an examinee experiment in a blood controlled region, to collect basic data for ...

1999-12-05

175

Two-phase fluid flow measurements in small diameter channels using real-time neutron radiography  

International Nuclear Information System (INIS)

A series of real-time, neutron radiography, experiments are ongoing at the Texas A and M Nuclear Science Center Reactor (NSCR). These tests determine the resolving capabilities for radiographic imaging of two phase water and air flow regimes through small diameter flow channels. Though both film and video radiographic imaging is available, the real-time video imaging was selected to capture the dynamic flow patterns with results that continue to improve. (author)

1994-04-05

176

The semiclassical approximation for L- and M-shell Coulomb ionization by heavy charged particles  

International Nuclear Information System (INIS)

The semiclassical approximation with straight-line trajectories is applied to the Coulomb ionization of K, L and M shells by heavy charged particles. The calculational aspects are discussed in detail. Scaling relations for the experimentally relevant quantities are derived. The theoretical predictions are compared with experiment. The relation of the present work to the earlier results of the semiclassical approximation and partial-wave Born approximation is discussed in detail. (author).

177

Serial multivibrator on field effect transistors  

International Nuclear Information System (INIS)

An operating cycle of a serial multivibrator carried out on the base of field-effect transistors has been analyzed. Calculation relations for the main multivibrator parameters have been obtained, and conditions of self-excitation has been determined. Experimental data for determination of the self-oscillation excitation region have been presented. These results are in a good agreement with the experiment. The analysis of the data obtained has shown that the serial multivibrator on field-effect transistors has comparatively narrow excitation region and requires an accurate turning.

178

Researches on Plasma Physics and Controlled Fusion in IPP NSC KIPT  

International Nuclear Information System (INIS)

Recent results of experimental and theoretical investigations, carried out in the Institute of plasma Physics of the NSC KIPT, are presented in the report. The main problems of discussion are as follows: plasma confinement and heating in stellarators and electromagnetic traps; powerful quasi-steady-state plasma accelerators (QSPA); experiments relevant for ITER; fusion Plasma theory; methods of high temperature plasma diagnostics; plasma technology. The main prospects on the IPP investigators are discussed also.

2006-01-01

179

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

International Nuclear Information System (INIS)

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

1989-11-26

180

Radiation hardening of optical fiber links by photobleaching with light of shorter wavelength  

International Nuclear Information System (INIS)

The influence of additionally injected short-wavelength photobleaching light on the radiation hardness of Ge-doped graded index fibers working at 1,300 nm wavelength is investigated. Predictions are complicated by the fact that more efficient shortwave bleaching light experiences higher radiation-induced loss. Promising results are found for low fiber temperatures (approx-lt -50 C) and bleaching light of about 835 nm wavelength.

1995-09-18

181

Radial distribution of bonded fission gas in mixed carbide fuel pins  

International Nuclear Information System (INIS)

The fission gas xenon bonded in bubbles, in pore, and in the lattice of mixed carbide fuels is measured by electron-probe microanalysis. Radial xenon distribution and release curves are determined and are calibrated by gas chromatography of the bonded fission gas and by burnup analysis in the respective pin sections of the irradiation experiments FR2 6A and 6C, Mol 11/K 2, and DFR 330/1. The results are correlated to the microstructure of the fuel, bonding medium, temperature, and burnup. (Auth.).

1979-01-01

182

Potential U.S. contributions to in-reactor experiments for fast reactor surveillance systems  

International Nuclear Information System (INIS)

It is maintained that special features of FFTF make it an ideal system to test sodium boiling detection techniques by acoustic/neutronic methods and to test the response of acoustic/neutronic sensors to vibrations. It is shown that accumulated research results indicate that such tests in FFTF are feasible, predictable, promising and safe. (author).

183

Polymer electrolytes based on aromatic lithium sulfonyl-imide compounds; Electrolytes polymeres a base de sulfonylimidures de lithium aromatiques  

Energy Technology Data Exchange (ETDEWEB)

This paper presents ionic conductivity results obtained with polymer electrolytes and also with propylene carbonate solutions. The domain of electrochemical activity of this salt has been determined using cycle volt-amperometry in propylene carbonate. Preliminary experiments on the stability of the polymer electrolyte with respect to the lithium electrode have been carried out for a possible subsequent use in lithium batteries. (J.S.) 4 refs.

1996-12-31

184

Performance of a large Bragg-curve spectrometer  

Energy Technology Data Exchange (ETDEWEB)

A large Bragg-curve spectrometer has been constructed and tested. The detector has a cylindrical geometry and operates with a homogeneous electric field. Energy resolutions of <0.8% and Z resolutions of Z/..delta..Z=80 have been achieved for eleastically scattered /sup 58/Ni ions. These results demonstrate the suitability of this large solid-angle detector for use in a wide variety of heavy-ion scattering experiments.

1987-04-01

185

Performance of a large Bragg-curve spectrometer  

International Nuclear Information System (INIS)

A large Bragg-curve spectrometer has been constructed and tested. The detector has a cylindrical geometry and operates with a homogeneous electric field. Energy resolutions of <0.8% and Z resolutions of Z/#DELTA#Z=80 have been achieved for eleastically scattered "5"8Ni ions. These results demonstrate the suitability of this large solid-angle detector for use in a wide variety of heavy-ion scattering experiments. (orig.).

186

Pd-Na/F double exploding foil photoionization experiment  

Science.gov (United States)

The achievement of inner-shell photoionization of Zn-like Pd by means of two exploding foils is described. This resulted in the soft X-ray transition 3d94s2-3d104p at 46 A. It is shown that the photoionization of inner shell electrons in highly stripped ions can lead to X-ray transitions which may be candidates for X-ray lasers under 50 A.

1990-03-01

187

Partial discharge in liquid nitrogen  

Science.gov (United States)

Results are presented of experiments on partial discharge in liquid nitrogen, including insulation breakdown characteristics of liquid nitrogen, partial discharge characteristics of composite insulation systems, lifetime of polymer films, impulse breakdown of polymer films in liquid nitrogen, etc. The partial discharge characteristics of liquid nitrogen are examined with increasing liquid-nitrogen pressure. It is concluded that a composite insulation structure of polymer film and liquid nitrogen can be used as effective electrical insulators at cryogenic temperatures.

1976-01-01

188

Overall control and monitoring systems for pumped storage plants  

Energy Technology Data Exchange (ETDEWEB)

Experience and technical innovations in power plant engineering have resulted in continuous improvements of operation control, availability and safety of pumped storage plants. Process control is constantly improved as new developments are made in equipment and systems engineering. Plant control concepts with increasingly complex automation hierarchy are described by which pumped storage processes can be controlled optimally, reliably, and automatically.

1982-01-01

189

Numerical methods for determining the inhomogeneity boundary in a boundary value problem for Laplace?s equation in a piecewise homogeneous medium  

British Library Electronic Table of Contents (United Kingdom)

A boundary value problem for Laplace?s equation in a bounded two-dimensional domain filled with a piecewise homogeneous medium is considered. The boundary of the inhomogeneity is assumed to be unknown. The inverse problem of determining the inhomogeneity boundary and the solution of the equation given the solution and its normal derivative on the boundary of the domain is discussed. Numerical methods are proposed for solving the inverse problem, and the results of numerical experiments are presented.

2011-01-01

190

New development of external-PIXE system using a differential pumping technique  

International Nuclear Information System (INIS)

A new external-PIXE system utilizing a differential pumping technique, which can completely protect the accelerator and vacuum pumps when the exit foil breaks down, has been developed. Applications to analyses of liquid and heavily-outgassing samples were successfully achieved. Also, experiments for evaluating the efficiency of the system were performed and results will be presented. (author)

1999-09-01

191

Nature Of Tube Degradation In Horizontal Steam Generators  

Energy Technology Data Exchange (ETDEWEB)

Nature of tube degradation was studied in support of horizontal steam generator lifetime calculations. Experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K(ISCC), and the crack growth rate were made to predict evolution of damage in tube walls. Experimental results were compared with in-service inspections experience. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The ...

2002-07-01

192

Nature Of Tube Degradation In Horizontal Steam Generators  

International Nuclear Information System (INIS)

Nature of tube degradation was studied in support of horizontal steam generator lifetime calculations. Experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K(ISCC), and the crack growth rate were made to predict evolution of damage in tube walls. Experimental results were compared with in-service inspections experience. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The ...

2002-09-23

193

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

194

Multiquark states in nuclei and the deep inelastic scattering  

International Nuclear Information System (INIS)

Based on a hypothesis of multiquark states in nuclei, the nucleus structure functions are considered and the results are compared with experiment. It is shown that the multiquark state contributions are sufficiently high (Up to 20% in deuterium and 40% in iron) and must possess a greater, than in a nucleon, sea of quark-antiquark pairs. Also the comparison with the cumulative particle production cross sections is performed. The predictions are given for a further experimental test of that hypothesis.

195

Market trials of irradiated chicken  

Energy Technology Data Exchange (ETDEWEB)

The potential market for irradiated chicken breasts was investigated using a mail survey and a retail trial. Results from the mail survey suggested a significantly higher level of acceptability of irradiated chicken than did the retail trial. A subsequent market experiment involving actual purchases showed levels of acceptability similar to that of the mail survey when similar information about food irradiation was provided.

1998-06-01

196

Major steam turbine losses. Causes, repair measures, recommissioning; Grossschaeden an Dampfturbosaetzen. Ursachen, Reparaturen, Weiterbetrieb  

Energy Technology Data Exchange (ETDEWEB)

Substantial damages at main components of steam turbines do not have to result inevitably in an exchange of the components concerned. Rather a preliminary or final repair is possible which also considers the cause of the damage. An important condition with the technically complex questions is an appropriate qualification and experience of all involved persons. The common task of operators, manufacturers and insurance companies is to preserve the balance from costs, expenditure of time and risk.

2010-07-01

197

Kinetics of low-temperature radiation hardening of metallic materials under irradiation  

British Library Electronic Table of Contents (United Kingdom)

A formula is obtained which describes the kinetics of low-temperature radiation hardening caused by creation of dislocation loops of interstitial type during irradiation. The radiation hardening of aluminum and vanadium is estimated using this formula and results of experiments on studying processes of nucleation and growth of interstitial dislocation loops in these materials by transparent electron microscopy. It is shown that the proposed formula is valid for description of the kinetics of low-temperature radiation hardening.

2011-01-01

198

Kinetic energy accumulators. Application to electric cars  

Energy Technology Data Exchange (ETDEWEB)

The development of electric cars always met with the difficulty in storing energy and in recovering it in the form of electric power. Research work done for the last two decades in the field of materials and of new technologies oriented mainly towards aeronautical and space applications have led to designing, realizing and experimenting with flywheels rotating at high speed in magnetic bearings. The results obtained represent openings that, now, fall in with different industrial fields and in particular with application to electric cars.

1982-12-01

199

Integral testing of the evaluated data files for silicon, zirconium, niobium and iron  

Energy Technology Data Exchange (ETDEWEB)

The evaluated data testing for Si, Zr, Nb and Fe materials has been performed through the analyses of the neutron leakage spectrum from spherical assemblies measured in integral benchmark experiments with (d,t) and Cf fission neutron sources. Intercomparisons of the calculated from BROND-2, ENDF/B-6 and JENDL-3 data files with experimental results are presented.

1994-12-31

200

Higgs results from the Tevatron Run II  

Energy Technology Data Exchange (ETDEWEB)

The data taken at the Tevatron experiments have been analyzed to search for Higgs bosons. For the Standard Model Higgs searches, no excess is observed, the data are in good agreement with the expectations, so that limits are set on the production rates. For various theoretical models beyond the Standard Model, there is no excess either, which allows to derive constraints in their respective parameter spaces.

2005-01-01

201

Fuel ignition by high voltage capacitive discharges  

Energy Technology Data Exchange (ETDEWEB)

The study examined the possibility for fuel ignition by spark discharge caused by induction effects under high voltage transmission lines. Theoretical background information on capacitive spark discharges and fuel ignition processes is given. Laboratory experiments were conducted to test the dependence of fuel ignition on three parameters: impedance in discharge path, multiple discharges, and larger electrode shapes. The results of these tests are discussed in terms of fuel ignition possibilities under high voltage transmission lines.

1983-03-01

202

Endocavitary radiotherapy of rectal tumours; Endokavitaer straalebehandling ved distale rectum tumorers  

Energy Technology Data Exchange (ETDEWEB)

The authors describe their experience of endocavitary radiotherapy of adenomas and carcinomas of the lower rectum. The method is an alternative for patients who cannot undergo standard surgical procedure or do no want a permanent colostomy. This method is cheap, fast and causes little discomfort to the patients, gives reasonable long-term results and has low morbidity. 11 refs., 4 figs., 2 tabs.

1997-02-01

203

Effect of environmental variables on localized corrosion of high-performance container materials  

Energy Technology Data Exchange (ETDEWEB)

Electrochemical cyclic potentiodynamic polarization (CPP) experiments were performed on several candidate high-performance waste package container materials to evaluate their susceptibility to localized corrosion in aqueous environments relevant to the potential underground high-level nuclear waste repository. This paper presents the results of this study showing the effects of chloride ion (Cl) concentrations, pH, temperature, and electrochemical potential scan rate on the pitting corrosion behavior of these materials.

1997-01-01

204

EFFECT OF DISSOLVED SOLIDS ON LIMESTONE FGD (FLUE GAS DESULFURIZATION) SCRUBBING CHEMISTRY  

Science.gov (United States)

The paper gives results of experiments in a 0.1 MW pilot plant to determine the effects of high concentrations of chloride ions and dissolved salts on flue gas desulfurization (FGD) scrubbing chemistry, both in the natural and forced oxidation modes of operation. (Note: The tight...

205

Dust and waterfree technology for demolition works in nuclear environments and other sensitive areas  

International Nuclear Information System (INIS)

At the University of Karlsruhe experiments were carried out from 1997 to 1999 to get fundamentals of flow characteristics of pneumatic extracted materials. The results could be used to develop a concept for demolition suitable for extraction and removing high-density concrete. The concept fulfills all demands of a closed nuclear area, especially of dust abatement. (orig.)

206

Diffraction studies of nanocrystals: theory and experiment  

International Nuclear Information System (INIS)

Based on theoretical calculations of powder diffraction data it is shown that the assumption of the infinite crystal lattice for small particles is not justified, leads to significant changes of the diffraction patterns, and may lead to erroneous interpretation of the experimental results. An alternate evaluation of diffraction data of nanoparticles, based on the so-called 'apparent lattice parameter', alp, is proposed. (author)

2001-09-23

207

Development of a site-specific following accident dose assessment system  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this project to interface the site-specific real-time radiological dose assessment system FADAS(Following Accident Dose Assessment System) to CARE. In this study, the results of the field tracer experiments conducted on the Younggwang site have been analysed. And the experimental procedure on Ulchin site has been introduced. The environmental characteristics on Ulchin and Wolsung has been investigated.

1997-12-15

208

Comparison of calculated and measured irradiated wire data for HEU and mixed HEU/LEU cores in the ORR (Oak Ridge Research Reactor)  

Energy Technology Data Exchange (ETDEWEB)

Low power wire activations are being performed in the Oak Ridge Research Reactor (ORR) as part of the whole-core LEU demonstration experiments. Calculations of the demonstration cores, including simulation of the wire activations, are being performed at Argonne National Laboratory (ANL). This paper presents the results of comparisons for 293 wires from five cores and shows that, on the average, the integrated activities agree within 6%.

1986-01-01

209

Collisional-radiative model for highly stripped ions  

Energy Technology Data Exchange (ETDEWEB)

Collisional-Radiative numerical models are commonly used to design or interpret experiments in atomic physics of laser-created plasmas, including X-ray laser studies. We describe our new code containing several options: average ion, more or less detailed configurations. It consists of an atomic data base coupled to subroutines evaluating ionic populations and emission and absorption coefficients. Numerical results are given to illustrate the capabilities of the code and to compare different models and types of approximation.

1986-10-01

210

Chemical detection of leukocytes in urine by means of a new multiple test strip.  

Science.gov (United States)

The performance of the leukocyte test area of the new multiple urine test strip, Multistix-10-SG, was evaluated in both field trials and model experiments. The detection limit was found to be adequate for routine purposes. Unspecific reactions are rare and generally indicated by the results of the other test areas. PMID:3572312

1987-02-01

211

Chalk Point Cooling Tower Project. Environmental Systems Corporation's FY77 final report, July 1, 1976--August 31, 1977. Volume II. Cooling Tower Drift Dye Tracer Experiment. [Dye tests of vapor plume dispersion in coastal regions  

Science.gov (United States)

Results are reported from dye tests of the dispersion of the vapor plume from the natural draft cooling tower of a fossil-fuel power plant located in the coastal region of Maryland.

1977-12-01

212

Causes of PGV-1000 horizontal steam generator 'cold' collector damages and ways of improving their operation reliability and service life  

International Nuclear Information System (INIS)

Specifications of the PGV-1000 steam generators applied at the WWER-1000 NPP power units, operational experience and data on damages at the 'cold' heat carriers of steam generators are considered and their results are presented. Developed and introduced measures aimed at improving reliability and operational life of the PGV-1000 collectors are described.

1993-01-01

213

Anode wire ageing in proportional detectors at the BAC calorimeter of the ZEUS experiment  

Energy Technology Data Exchange (ETDEWEB)

Experimental results of ageing effects in proportional counters are presented. The measurements were carried out for 158 ZEUS-BAC gas system monitoring counters. Deterioration of the pulse height distribution in azimuth and along the anode wire are presented. The influence of water admixture on counting gas is also described. (orig.).

1997-06-21

214

Analysis of Computer Experiments with Multiple Noise Sources  

DEFF Research Database (Denmark)

In this paper we present a modeling framework for analyzing computer models with two types of variations. The paper is based on a case study of an orthopedic surgical unit, which has both controllable and uncontrollable factors. Our results show that this structure of variation can be modeled effectively with linear mixed effects models and generalized additive models. Copyright (C) 2009 John Wiley & Sons, Ltd.

2010-01-01

215

Adsorption capability of charcoal: a comparison study of some activated and non-activated charcoal samples  

Energy Technology Data Exchange (ETDEWEB)

Experiments were carried out to determine the adsorption capability of some commercial activated and non-activated charcoal samples with methanol to select the most favourable pair to be used in a solar adsorption refrigeration system. The results obtained are presented. A simple method has been used to enhance the adsorption capability of the lumpwood charcoal. (Author)

1994-01-01

216

A time-resolved optical study of the avalanche and streamer formation in atmospheric nitrogen  

Energy Technology Data Exchange (ETDEWEB)

This work deals with a time-resolved optical study of the avalanche and streamer formation phases leading to breakdown in atmospheric nitrogen. The authors present the results obtained for nitrogen, from experiments and two-dimensional model simulations. This model is used to obtain a better insight in the relevant mechanisms and processes by a comparison of measurements and simulation data. The trends of externally measured quantities correspond with those predicted by the model.

1996-12-31

217

A critical review of the hypothesis that climate change is caused by carbon dioxide  

Energy Technology Data Exchange (ETDEWEB)

This critical review with 28 references examines absorption and emission in the v2 band of the carbon dioxide molecule at around the 15micron wavelength. The argument for additional infrared absorption, the enhanced greenhouse effect due to increased carbon dioxide concentrations, and radiation transport and increased emissions are discussed. Experiments studying the transmission spectra of pure carbon dioxide and carbon dioxide in nitrogen, and comparing them with the results of climate modelling using the HITRAN and GEISA databases, are described.

2000-07-01

218

The influence of amino acids on the biomineralization of hydroxyapatite in gelatin.  

Science.gov (United States)

The effects of pH on the calcium phosphate phase, of Tris and of amino acids, such as aspartic acid, glutamic acid, and serine on hydroxyapatite formation and morphology, were studied in double diffusion experiments. In this system, hydroxyapatite was only formed when the pH was around 7.4 or higher for the duration of the reaction. A decrease in pH resulted in the transformation of hydroxyapatite to octacalcium phosphate. Amino acids and Tris or the buffering capacity of Tris have an effect on the morphology of the synthetic hydroxyapatite. The presence of the additive results in spheres consisting of needles, blades or plates depending on the reaction system. PMID:12175941

2002-08-30

219

The double crystal technique - its application to resconstructed InSb (001) and Xe layers  

International Nuclear Information System (INIS)

The early work of Stern has been reviewed briefly along with some of our experiments carried out later with similar geometrical arrangements in order to highlight his successes at the time and the future developments of his findings and predictions. The double crystal technique, developed by Stern has been used for energy analysis of He beams and results are shown for scattering from a rough reconstructed (001) InSb surface and Xe adsorbed layers. Surface phonons were not observed in the case of InSb probably as a result of the rough surface. (orig.).

1988-01-01

220

Scattering and Recombination of Two Triplet Excitons in polymer light-emitting diodes  

CERN Document Server

The scattering and recombination processes between two triplet excitons in conjugated polymers are investigated by using a nonadiabatic evolution method, based on an extended Su-Schrieffer-Heeger model including interchain interactions. Due to the interchain coupling, the electron and/or hole in the two triplet excitons can exchange. The results show that the recombination induces the formation of singlet excitons, excited polarons and biexcitons. Moreover, we also find the yields of these products, which can contribute to the emission, increase with the interchain coupling strength, in good agreement with results from experiments.

2010-01-01

221

Quasi-landau resonances: analytic treatment of the hydrogenic spectrum in the two-dimensional model and relation to other strong-field problems  

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional WKB model has been the basis for several investigations of the quasi-Landau hydrogenic spectrum. Whereas other authors have used numerical integration, it is shown that the results can be obtained analytically in terms of elliptic integrals. The later are easily generated by even programmable pocket calculators, from which numerical results - which are in good agreement with experiments - are easily obtained. A further advantage of using elliptic integrals is that several strong-field problems can be shown to be special cases of a general potential whose energy and spacing are expressible in terms of them.

1982-11-01

222

Proposition of the Interactive Pareto Iterated Local Search Procedure - Elements and Initial Experiments  

CERN Document Server

The article presents an approach to interactively solve multi-objective optimization problems. While the identification of efficient solutions is supported by computational intelligence techniques on the basis of local search, the search is directed by partial preference information obtained from the decision maker. An application of the approach to biobjective portfolio optimization, modeled as the well-known knapsack problem, is reported, and experimental results are reported for benchmark instances taken from the literature. In brief, we obtain encouraging results that show the applicability of the approach to the described problem.

2008-01-01

223

Out-of-pile simulation of mild TOPs; development of pin failure, material movement and relocation in bundle geometry  

International Nuclear Information System (INIS)

An experimental technique is described which allows for parametric investigations of transient behavior of mobile core materials in a fuel bundle geometry. For the out-of-pile simulation of energy releases resulting from mild TOP- or LOF-accidents the exothermic reaction of an aluminium-oxide-thermite is used. Transient material relocation inside the test section is recorded by X-ray-cinematography. Results of some experiments recently performed close to conditions expected to be achieved during mild TOP-accidents are described in detail.

1979-08-23

224

Numerical simulation of trace tests in atmosphere in Daya Bay nuclear power site  

International Nuclear Information System (INIS)

The validation of the forecast model for early emergency response to nuclear accidents is evaluated by trace tests in atmosphere in Daya Bay nuclear power site. The simulation experiment of the Daya Bay nuclear power site shows that the particle spreading image and the time-integrated concentration distribution given by plume concentration prediction model can perform the variation of pathway of the pollutant transport, as well as the effects of topography on transport and diffusion of pollutants. The simulation of five trace tests in field shows that 59.1% of ratios between predicted results and observed results are within the range of 10, and 41% of ratios are within the range of 5 approximately. (authors)

2005-09-01

225

Numerical simulation of internal reconnection event in spherical tokamak  

Energy Technology Data Exchange (ETDEWEB)

Three-dimensional magnetohydrodynamic simulations are executed in a full toroidal geometry to clarify the physical mechanisms of the Internal Reconnection Event (IRE), which is observed in the spherical tokamak experiments. The simulation results reproduce several main properties of IRE. Comparison between the numerical results and experimental observation indicates fairly good agreements regarding nonlinear behavior, such as appearance of localized helical distortion, appearance of characteristic conical shape in the pressure profile during thermal quench, and subsequent appearance of the m=2/n=1 type helical distortion of the torus. (author)

1999-07-01

226

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

227

In situ observation of axial irradiation growth in liquid-metal reactor metal fuel  

International Nuclear Information System (INIS)

Effects of the rapid early-in-life expansion of metal fuel were measured in an irradiation experiment in the Fast Flux Test Facility (FFTF). This important performance/design information was obtainable through the unique combination of a dimensionally stable FFTF oxide core and the calibrated proximity instrumentation associated with the test. These results delineate the time dependence of metal-fuel swelling and provide quantitative estimates of the magnitude of axial fuel swelling in full-length metal-fuel assemblies. Final posttest examination results will define actual fuel column growth levels.

1989-11-26

228

Computer-aided band gap engineering and experimental verification of amorphous silicon-germanium solar cells  

Energy Technology Data Exchange (ETDEWEB)

A new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction cell has been designed and experimentally demonstrated. By computer simulations we show how bending the grading of the band gap in the i-layer contributes to the enhancement of the carrier collection, improving the fill factor and efficiency. The differences observed between experiments and simulations are studied using Rutherford Backscattering Spectrometry (RBS). The results highlight weak points during the deposition process, whose control enables us to bring together experimental and computational results.

2004-01-25

229

A comparison of seasonal radon concentration and weekly screening measurements  

Energy Technology Data Exchange (ETDEWEB)

Short-term radon measurements were used to make a comparison between weekly screening tests and seasonal concentration. The screening measurements were made in an indoor environment over a period of one quarter during early summer and the results are compared with the measured average radon level over that period. In these experiments, the envelope-type and plastic bag monitors were used for screening and long term radon concentration measurements, respectively. The results show that one cannot achieve predicting the seasonal mean radon concentration based on weekly measurements better than 50% under the conditions reported. (author).

1993-12-31

230

A comparison of seasonal radon concentration and weekly screening measurements  

International Nuclear Information System (INIS)

Short-term radon measurements were used to make a comparison between weekly screening tests and seasonal concentration. The screening measurements were made in an indoor environment over a period of one quarter during early summer and the results are compared with the measured average radon level over that period. In these experiments, the envelope-type and plastic bag monitors were used for screening and long term radon concentration measurements, respectively. The results show that one cannot achieve predicting the seasonal mean radon concentration based on weekly measurements better than 50% under the conditions reported. (author).

231

Surgical dislocation of the hip and the management of femoroacetabular impingement: results of the Christchurch experience  

British Library Electronic Table of Contents (United Kingdom)

Abstract Background:- Surgical dislocation of the hip has been developed to deal with the problems causing femoroacetabular impingement (FAI). This is a relatively recent procedure that was historically reserved for larger areas specializing in hip surgery. Methods:- We hypothesized that surgical dislocation can be used for symptomatic FAI in a typical Australasian tertiary orthopaedic centre with acceptable results. This prospective study reviews the results of 53 surgical dislocations in this setting, looking particularly at functional outcomes and early complications. Results:- There were significant improvements in the Western Ontario and McMaster University Osteoarthritis Index score at 1, 2, 3 and 4 years post-operatively. Western Ontario and McMaster University Osteoarthritis Index ...

2011-01-01

232

Using the /phi/resund experimental data to evaluate the ARAC emergency response models  

Energy Technology Data Exchange (ETDEWEB)

A series of meteorological and tracer experiments, was conducted during May and June 1984 over the 20-km wide /O/resund strait between Denmark and Sweden for the purpose of studying atmospheric dispersion processes over cold water and warm land surfaces and providing the data needed to evaluate meso-scale models in a coastal environment. In concert with these objectives the data from these experiments have been used as part of a continuing effort to evaluate the capability of the three-dimensional MATHEW/ADPIC (M/A) atmospheric dispersion models to simulate pollutant transport and diffusion characteristics of the atmospheric during a wide variety of meteorological conditions. Since previous studies have focused primarily on M/A model evaluations over rolling and complex terrain at inland sites, the /O/resund experiments provide a unique opportunity to evaluate the models in a coastal environment. The M/A models are used by ...

1988-07-01

233

Integral system and horizontal steam generator behavior in noncondensable gas experiments with the PACTEL facility  

International Nuclear Information System (INIS)

Lappeenranta University of Technology (LTKK) and VTT Energy carried out a series of preliminary experiments in 1999 to study the behavior of noncondensable (NC) gases in VVER geometry. The experiments were run on the Parallel Channel Test Loop (PACTEL), which is a medium scale integral test facility designed to simulate thermal-hydraulic phenomena characteristic of VVER 440 type nuclear plants. The experiments aimed at studying the effect of noncondensable gases on system thermal-hydraulics and on heat transfer in a horizontal steam generator (HSG). The system behavior can be affected by hydrogen produced in the core in case of a severe accident, by nitrogen from hydro-accumulators (ACCU) released into the primary circuit in case of a loss-of-coolant accident (LOCA) and more generally by any noncondensable gas in all cases where cooling is ensured by natural circulation. This paper presents the measured ...

2001-03-20

234

Analysis of FARO spreading experiments  

Energy Technology Data Exchange (ETDEWEB)

Two spreading experiments were performed at the FARO facility with prototypical core melts of a UO{sub 2}/ZrO{sub 2} weight percentage of 80/20. The objective was to obtain data on the spreading at flow rates of about 2 l/s of more than 100 kg prototypic high temperature oxide melt on a dry and wet stainless steel plate. For the second spreading test a shallow water layer of 10 mm was added on the substrate. Solutions for an isothermal spreading with a constant volume flux boundary condition in a sector with an angle {phi} are used to analyse the FARO L-32S experiment and to identify the source of discrepancies between the code results (THEMA, CORFLOW) and the experimental findings. The observed spreading behaviour of both FARO experiments can only be explained if an initial melt temperature below the liquidus temperature, i.e. about 120 K lower than the temperature measured by the UTS sensors is ...

2000-08-01

235

The Path to Fusion Energy for Concepts Currently at the Concept Exploration Level  

Energy Technology Data Exchange (ETDEWEB)

Concept Exploration (CE) experiments within the Innovative Confinement Concept Program have a unique role which impacts their contributions to the development of fusion energy. As stated in the FESAC ''Report on Alternate Concepts:'' These [CE] programs are aimed at innovation and basic understanding of relevant scientific phenomena. The emphasis on innovation motivates their application to the search for a better fusion reactor configuration. In addition, because of their unique character the CE experiments offer excellent opportunities to couple fusion-plasma physics to other sciences. A recent example of coupling is the fusion self-organized plasmas to reconnection physics and extra-terrestrial plasmas. Perhaps of even greater importance is the education of the future scientists needed for developing fusion energy. The CE experiments, both at universities and national labs, are of a ...

2003-01-09

236

Interpretation of data obtained from non-destructive and destructive post-test analyses of an intact-core column of culebra dolomite  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) has been developing a nuclear waste disposal facility, the Waste Isolation Pilot Plant (WIPP), located approximately 42 km east of Carlsbad, New Mexico. The WIPP is designed to demonstrate the safe disposal of transuranic wastes produced by the defense nuclear-weapons program. Pefiormance assessment analyses (U.S. DOE, 1996) indicate that human intrusion by inadvertent and intermittent drilling for resources provide the only credible mechanisms for significant releases of radionuclides horn the disposal system. These releases may occur by five mechanisms: (1) cuttings, (2) cavings, (3) spallings, (4) direct brine releases, and (5) long- term brine releases. The first four mechanisms could result in immediate release of contaminant to the accessible environment. For the last mechanisq migration pathways through the permeable layers of rock above the Salado are important, and major emphasis is placed on the Culebra Member of the ...

1998-09-01

237

Improving uranium extraction efficiency of yellow cake production from one shale deposit by acid pugging and curing with D263B resin adsorption  

International Nuclear Information System (INIS)

The improving uranium extraction efficiency of yellow cake production from shale deposit by acid pugging and curing with D263B resin adsorption is described in this paper. The analysis and examination show that the composition of uranium minerals in one of uranium ores is very complex, which directly influence the extraction efficiency of uranium and processing technology. Conventional experimental results indicate that uranium leaching efficiency is changed between 50?60% by conventional agitation method. In this case, acid pugging and curing experiments are employed in order to improving the extraction efficiency. A series of acid pugging and curing experiments are carried out to get parameters for heap leaching in pilot plant experiment. The experiment results by acid pugging and curing technology showed that uranium leaching efficiency can reach to 90% of ...

2006-06-01

238

Turbulent flow in a channel with transverse rib heat transfer augmentation  

Science.gov (United States)

Turbulent flow in a 2D channel with repeated rectangular rib roughness was numerically simulated using a low Reynolds number form of the k-epsilon turbulence model. Friction factors and average Stanton numbers were calculated for various pitch to rib height ratios and bulk Reynolds numbers. Comparisons with experiment were generally adequate, with the predictions of friction superior to those for heat transfer. The effect of variable properties for channel flow was investigated, and the results showed a greater effect for friction than for heat transfer. Comparison with experiment yielded no clear conclusions. The turbulence model was also validated for a related problem, that of flow downstream of an abrupt pipe expansion.

1993-04-01

239

Thulium laser resection via a flexible cystoscope for recurrent non-muscle-invasive bladder cancer: initial clinical experience  

British Library Electronic Table of Contents (United Kingdom)

OBJECTIVE To present our initial experience of thulium laser resection via a flexible cystoscope for recurrent non-muscle-invasive bladder cancer (ThuRBT), as transurethral resection for bladder tumour (TURBT) is regarded as the reference standard for treating this disease, but alternative laser resection or ablation is suitable especially for recurrent tumours. PATIENTS AND METHODS From January 2005 to October 2005, 32 patients with early recurrent bladder tumour (recurrent within a year after TURBT) were treated with ThuRBT via a flexible cystoscope. The follow-up included urine analysis, ultrasonography and cystoscopy every 3 months. RESULTS All patients were treated successfully with ThuRBT in one session, with no bladder haemorrhage, obturator nerve reflex or vesicle perforation. Rand...

2008-01-01

240

The effect of Reynolds numbers and the direction of interfacial shear stress on turbulence below an air-water interface  

Energy Technology Data Exchange (ETDEWEB)

Momentum transfer through an air-water interface was studied in a horizontal rectangular channel through experimental and numerical analysis. The liquid flow Reynolds numbers, based on hydraulic diameters, were 11500 and 17000. The air flow Reynolds number varied from 0 to 3260. In experiments, velocity distribution was measured by hot-film and hot-wire probes. The effect of the liquid flow Reynolds number and the direction of interfacial shear stress was investigated by performing the cocurrent and countercurrent experiments. The modified k-{epsilon} model was able to reproduce these experimental results qualitatively. The range of applicability of the modified k-{epsilon} model was also discussed. (author).

1991-09-01

241

The effect of Reynolds numbers and the direction of interfacial shear stress on turbulence below an air-water interface  

International Nuclear Information System (INIS)

Momentum transfer through an air-water interface was studied in a horizontal rectangular channel through experimental and numerical analysis. The liquid flow Reynolds numbers, based on hydraulic diameters, were 11500 and 17000. The air flow Reynolds number varied from 0 to 3260. In experiments, velocity distribution was measured by hot-film and hot-wire probes. The effect of the liquid flow Reynolds number and the direction of interfacial shear stress was investigated by performing the cocurrent and countercurrent experiments. The modified k-#epsilon# model was able to reproduce these experimental results qualitatively. The range of applicability of the modified k-#epsilon# model was also discussed. (author).

242

The basic experiment on the high-temperature chemical reaction between sodium compound and iron-base material. Pt. 2. Structure observations  

Energy Technology Data Exchange (ETDEWEB)

This experiment is carried out in the series of the investigation on the damage mechanism of carbon steel. In this paper, the damage situation is considered by structure observations. The test were carried out in 600degC-1200degC temperature range, in blowing an argon gas. The reagents are Na{sub 2}O, Na{sub 2}O{sub 2} and NaOH. From structure observations, the holes are observed on the surface of iron-base material in some test conditions. This result is indicated that the selective reaction occurs. The selective reaction is more obvious as the time exposed to the high temperature is longer. It is considered that the selective reaction occurs after the chemical reaction between iron-base material and sodium compound. The areas, in which Mn-concentration is higher, are observed in products on the surface of specimen. (author)

1997-07-01

243

The addition of trim coils to the Tandem Mirror Experiment magnet system to improve the magnetic field mapping  

International Nuclear Information System (INIS)

The mapping of the magnetic flux bundle from the center cell to the Plasma Potential Control plates (PPC) on the end fan of the Tandem Mirror Experiment Upgrade (TMX-U), was improved by the addition of trim coils (12,000 amp-turns) on each side of each end fan next to the pump beam magnetic shields. The coils' axes are oriented perpendicular to the machine centerline. These coils made the necessary corrections to the field-line mapping, while keeping the field in the nearby pump beam magnetic shield below the saturation threshold. This paper briefly describes the problem, discusses the design as it evolved, and presents the results of the field testing. A brief description of the improvement in the machine performance is also included.

244

The Development of 6061-Aluminum Windows for the MICE LiquidAbsorber  

Energy Technology Data Exchange (ETDEWEB)

The thin windows for the Muon Ionization Cooling Experiment (MICE) liquid Absorber will be fabricated from 6061-T6-aluminum. The absorber and vacuum vessel thin windows are 300-mm in diameter and are 180 mm thick at the center. The windows are designed for an internal burst pressure of 0.68 MPa (100 psig) when warm. The MICE experiment design calls for changeable windows on the absorber, so a bolted window design was adopted. Welded windows offer some potential advantages over bolted windows when they are on the absorber itself. This report describes the bolted window and its seal. This report also describes an alternate window that is welded directly to the absorber body. The welded window design presented permits the weld to be ground off and re-welded. This report presents a thermal FEA analysis of the window seal-weld, while the window is being welded. Finally, the results of a test of a welded-window are presented.

2005-08-24

245

Terror management among Taiwanese: Worldview defence or resigning to fate?  

British Library Electronic Table of Contents (United Kingdom)

Terror management theory (TMT) proposes that people who are reminded of their mortality should be motivated to defend their cultural worldview. Studies 1 and 2 examined whether the TMT worldview defence-buffering effect found in Western cultures could be generalized to Asians in Taiwan. No such effect was found in the present studies. This non-significant result was robust when either a stronger distraction task was used (study 1) or when a subliminal manipulation of mortality salience was utilized (study 2). A meta-analysis, including 24 TMT experiments in East Asia, was also conducted (study 3). The average effect size (d = 0.11, r = 0.055) of worldview defence among these experiments was not significantly different from zero. Study 4 found that mortality salience manipulation also did n...

2010-01-01

246

Surface effects of total coal-seam extraction by underground mining methods  

Energy Technology Data Exchange (ETDEWEB)

The paper gives a detailed overview of the history of subsidence engineering in South African collieries. Surface displacements resulting from total-seam extraction are discussed, and the important role of local geology is highlighted. It is shown that the differences in subsidence behaviour between South African and European collieries can be attributed to the presence of competent strata in the overburden of South African coal seams. Criteria are given for the prediction of the most important subsidence parameters, and a new model for the simulation of surface subsidence above total-extraction panels is introduced. The final section of the paper deals with the damage to surface structures caused by total-seam extraction. A brief summary of the most important undermining experiments in South African collieries is given, and it is concluded that local experiences of damage compare with those in Europe. 32 refs., 9 figs., 3 ...

1991-07-01

247

Study on probability of failure for RPV nozzle region under severe accident conditions  

Energy Technology Data Exchange (ETDEWEB)

Most of previous study for creep rupture of RPV lower head under severe accident condition, have been focused on global failure of RPV lower head. In contract, the local failure of the RPV nozzle region has not been studied in detail. The existence and features of nozzle failure in LAVA-ICI specimen of KAERI and LHF-4 specimen of Sandia National Lab., are observed. It is confirmed that the nozzle failure of LHF-4 specimen is due to the hoop stress in the RPV. The tensile tests in various temperatures and the creep rupture tests in various temperatures and stresses, are accomplished. The finite element analysis for LAVA-ICI experiment was confirmed, and the stress and deformation analysis results are used in LAVA-ICI experiment. 17 refs., 34 figs., 3 tabs. (Author)

2001-04-01

248

Study of Zircaloy-2 corrosion in high temperature water using ion beam methods  

Energy Technology Data Exchange (ETDEWEB)

Experiments have been carried out in water at 355 C to study transport of oxygen and hydrogen (as deuterium) in growing corrosion films. Composition of the films was also examined in 2.9 Mev and 3.9 Mev /alpha/-particle backscattering experiments. Corrosion occurs predominantly by oxygen diffusion through the film via grain boundary or similar short circuit diffusion paths, to form fresh oxide at the oxide metal interface. Increasing grain size within thick pre-breakaway films contributes to a decrease in diffusivity. The rate transition results from the generation of new diffusion pathways in previously protective oxide. Unexpectedly high concentrations of deuterium were observed. 26 refs.

1981-10-01

249

Status of measurements of fission neutron spectra of Minor Actinides  

International Nuclear Information System (INIS)

The report considers experimental and theoretical works on studying the energy spectra of prompt neutrons emitted in spontaneous fission and neutron induced fission of Minor Actinides. It is noted that neutron spectra investigations were done for only a small number of such nuclei, most measurements, except those of Cf-252, having been carried out long ago by obsolete methods and imperfectapparatus. The works have no detailed description of experiments, analysis of errors, detailed numerical information about results of experiments. A conclusion is made that the available data do not come up to modern requirements. It is necessary to make new measurements of fission prompt neutron spectra of transuranium nuclides important for the objectives of working out a conception of minor actinides transmutation by means of special reactors. (author).

1997-03-01

250

Reactivity from power spectral density measurements with /sup 252/Cf. [LMFBR  

Science.gov (United States)

The theory of a method of determination of the reactivity from power spectral density measurements with /sup 252/Cf and the results of experiments with a critical assembly mock-up of a liquid-metal fast breeder reactor and with uranium (93.2 wt % /sup 235/U) metal cylinders and a sphere are presented. This method of reactivity determination has an advantage over existing methods in that it determines the reactivity only from properties of the reactor at the subcritical state of interest and thus does not require a calibration near delayed criticality. In these experiments the reactivity was varied by changing the fissile loading or the amount of neutron absorber inserted; for the LMFBR mock-up, the reactivity varied to approximately 75 dollars subcritical, and for the uranium metal assemblies, to approximately 30 dollars subcritical.

1977-08-01

251

Post-CHF heat transfer with water and refrigerants  

Energy Technology Data Exchange (ETDEWEB)

Heat transfer experiments were performed in the post-CHF two-phase flow regime in a vertical tube. The tube inside diameter was 7.75 mm, and the boiling fluid was R-113. The experiments were performed at steady state by means of liquid heating of the test tube. Wall superheats were maintained below 70 C for heat exchanger/steam generator application. The mass flux range of the data was 379-816 kg m{sup -2} s{sup -1}. The use of R-113 significantly extended the property range of the existing low wall-superheat data base. Experimental data are presented in tabular as well as graphical form, and the results were used with low wall-superheat data from other fluids to add generality to a predictive heat transfer correlation. (orig.)

1996-06-01

252

Particle Flow at CMS and the ILC  

CERN Document Server

This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to improve the energy ...

2010-01-01

253

PROSPECTS AND STATUS OF LOW-ASPECT-RATIO TOKAMAKS  

Energy Technology Data Exchange (ETDEWEB)

The prospects for the low-aspect-ratio (A) tokamak to fulfill the requirements of viable fusion power plants are considered relative to the present status in data and modeling. Desirable physics and design features for an attractive Blanket Test Facility and power reactors are estimated for low-A tokamaks based on calculations improved with the latest data from small pioneering experiments. While these experiments have confirmed some of the recent predictions for low-A, they also identify the remaining issues that require verification before reliable projections can be made for these deuterium-tritium applications. The results show that the low-A regime of small size, modest field, and high current offers a path complementary to the standard and high A tokamaks in developing the full potential of fusion power.

1995-01-01

254

Modelling of two-phase natural circulation in a WWER-plant: PMK experimental results  

International Nuclear Information System (INIS)

Experiments have been performed with the PMK integral-type facility, a model of WWER-440 type PWRs, to investigate two-phase natural circulation behaviour. The phenomena to be expected in this reactor type are different from those in PWRs with vertical steam generators mainly due to the loop seal in the hot leg and the horizontal layout of the steam generator heat transfer tubes. The experiments showed that the system is repressurized when the water level drops to the hot leg elevation due to the effect of the loop seal. Opening of the loop seal can be smooth, but may lead to oscillations depending on the power and the mass inventory. Natural circulation recovers after the hot leg loop seal is opened, but then decreases with further mass inventory decrease. (orig.).

255

Lithium isotopic separation: preliminary studies; Separacao isotopica de litio: estudos preliminares  

Energy Technology Data Exchange (ETDEWEB)

In order to get the separation of natural isotopes of lithium by electrolytic amalgamation, an electrolytic cell with a confined mercury cathode was used to obtain data for the design of a separation stage. The initial work was followed by the design of a moving mercury cathode electrolytic cell and three experiments with six batches stages were performed for the determination of the elementary separation factor. The value obtained, 1.053, was ill agreement: with the specialized literature. It was verified in all experiments that the lithium - 6 isotope concentrated in the amalgam phase and that the lithium - 7 isotope concentrated in the aqueous phase. A stainless-steel cathode for the decomposition of the lithium amalgam and the selective desamalgamation were also studied. In view of the results obtained, a five stages continuous scheme was proposed. (author)

1998-07-01

256

Late Entry in Swedish Tertiary Education: Can the Opportunity of Lifelong Learning Promote Equality Over the Life Course?  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this article, I investigate the relation between economic inequality and the decision to take up studies at the tertiary level late in life. Who exactly decides to enrol? Is it advantaged or disadvantaged groups in terms of current earnings rank, occupation, unemployment experience and social origin? Using unique register data of university applications and discrete time hazard regression models, the results show the likelihood of a late entry to be especially high for individuals who are disadvantaged to a moderate extent in terms of current earnings rank and also with some unemployment experience. Class differences in the transition to tertiary education decline with age. This suggests, with a moderate amount of simplification, that lifelong learning tends to promote both int...

2011-01-01

257

Interfacial area transport equation: model development and benchmark experiments  

Energy Technology Data Exchange (ETDEWEB)

The interfacial area transport equation dynamically models two-phase flow regime transitions and predicts continuous changes of the interfacial area concentration along the flow field. It replaces the flow regime-dependent correlations for the interfacial area concentration in thermal-hydraulic system analysis. In the present study, detailed formulation of the interfacial area transport equation is presented along with its evaluation results based on the detailed benchmark experiments. In view of model evaluation, the equation is simplified into one-dimensional steady state one-group interfacial area transport equation. The prediction made by model agrees well with the experimental data obtained in round pipes of various diameters. The framework for the two-group transport equation and the necessary constitutive relations are also presented in view of bubble transport of various sizes and shapes. (author)

2002-07-01

258

Interaction of insulin with a triblock copolymer of PEG-(fumaric-sebacic acids)-PEG: Thermodynamic and spectroscopic studies  

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the interaction of (PEG-co-P(FA/SC)-co-PEG) triblock copolymer with bovine and human insulins was carried out using isothermal titration calorimetry (ITC), circular dichroism (CD), and fluorescence spectroscopy. ITC data show that the copolymer has a low affinity for both proteins, with an association constant of about 7?9?103?M ?1. Results also show that binding is enthalpically driven, and disfavored by conformational entropy. CD spectroscopy studies reveal a small increase in the helical content and a decrease in ?-structure as well as random coil in both proteins. Acrylamide quenching experiments display reduced accessibility of tyrosines, while intrinsic fluorescence spectra show lower tyrosine emission. Furthermore, thermal unfolding experiments, studied by far...

2007-01-01

259

Influence of some chemical compounds on germination and early seedling growth of two range species under allelopathic conditions  

British Library Electronic Table of Contents (United Kingdom)

Seed priming technique has been known to improve germination and seedling emergence under different environment stresses. The objective of this study was to evaluate the effectiveness of seed priming in improving the seed germination and seedling vigor of Agropyron elongatum and Bromus inermis in response to five concentrations of the allelopathic extract of Thymus kotschyanus (0, 5%, 25%, 50% and 75%) under laboratory conditions. Pretreatments included gibberellic acid (250, 500 and 1000 ppm), potassium nitrate (0.1%, 0.2% and 0.3%) and salicylic acid (100, 200 and 300 mg/L). This experiment was carried out as a factorial experiment based on a completely randomized design with four replications. The results showed that seed germination, germination speed and seedling vigor were significan...

2011-01-01

260

Images of addiction and recovery: An interpretative phenomenological analysis of the experience of addiction and recovery as expressed in visual images  

British Library Electronic Table of Contents (United Kingdom)

This article focuses on visual representations of subjective experiences of the process of recovery from addiction and the meanings that participants attribute to their visual work. The data are drawn from a study of six female participants. In this article, we discuss the results with reference to one participant, to allow for detailed consideration of the visual and the verbal material. This participant was selected because of the richness of her material, which provided an opportunity to carry out a detailed case study. Potential participants were informed in advance that they would be asked to draw during the interview. They were also asked to bring to the interview some artwork made during their engagement in creative activities at an earlier stage in their recovery. The data were ana...

2011-01-01

261

First ICRF heating experiment in the large helical device  

Energy Technology Data Exchange (ETDEWEB)

Initial ICRF heating experiment in the LHD was carried out in 1998. One pair of the movable loop antennas was used and the coupling resistance was around one ohm for the low density ECH plasma. The loading characteristics were consistent with the fast wave excitation. By applying the ICRF heating of 300 kW to the ECH target plasma, the diamagnetic energy was increased from 13 kJ to 26 kJ. The heating performance was decided by hydrogen mixture rate on puffing gas. Efficient electron heating was observed at the higher hydrogen gas ratio. These results can be explained by the one dimensional wave analysis calculation on slab plasma model. (J.P.N.)

1999-07-01

262

Experimental measurement of low-energy antiprotons in the cosmic radiation  

Energy Technology Data Exchange (ETDEWEB)

Researchers report results from the Low Energy Antiproton Experiment (LEAP), a balloon-borne instrument which was flown in August, 1987. They found a value of 4.2 by 10-6 for the antiproton to proton ratio in the energy range from 120 MeV to 600 MeV at the top of the atmosphere. In particular, this experiment places an upper limit on the flux almost an order of magnitude below the reported flux of Buffington et al. This upper limit allows us to place significant constraints on both the primordial black hole and weakly interacting Majorana Fermion hypothesis, as well as on the low energy processes in more conventional models of galactic cosmic ray antiproton production.

1990-01-01

263

Effect of strongly coupled plasma on the spectra of hydrogenlike carbon, aluminium and argon  

Science.gov (United States)

A detailed study has been performed for estimating the orbital energies, positions and shifts of the Lyman lines of C5+, Al12+ and Ar17+ under strongly coupled plasma with a view to understand such line positions and shifts obtained in laser produced plasma experiments. The effect of strongly coupled plasma has been treated within the Ion Sphere (IS) model. Both non-relativistic and relativistic methods have been used for estimating the spectral properties. Theoretical estimates with IS model of the plasma are in conformity with the results of laser plasma experiments on these highly stripped ions. The experimental data for the systems have also been compared with the theoretical estimates using Debye screening model of the plasma with spatial confinements which gives additional restrictions to the wave functions at finite boundaries.

2008-01-01

264

Design and field trial application of foam in production wells to improve conformance  

Energy Technology Data Exchange (ETDEWEB)

The experimental foam treatments conducted on two production wells, each in a different miscible flood pool, were described, including aspects of the laboratory work, numerical coning simulation, well selection process and foam placement strategy. One of the wells was injected with a foam-forming surfactant, as well as with a surface-generated preformed foam. Neither of these treatments had any effect on the performance of this well. In the other well, preformed foam treatment was successful in reducing gas-oil ratio, resulting in improved oil production over a 14-month period. Future foam injection projects are being planned, based on the experiences gained in this field experiment. 13 refs., 21 figs.

1997-02-01

265

Decoherence-free neutron interferometry  

International Nuclear Information System (INIS)

Perfect single-crystal neutron interferometers are adversely sensitive to environmental disturbances, particularly mechanical vibrations. The sensitivity to vibrations results from the slow velocity of thermal neutrons and the long measurement time that are encountered in a typical experiment. Consequently, to achieve a good interference solutions for reducing vibration other than those normally used in optical experiments must be explored. Here we introduce a geometry for a neutron interferometer that is less sensitive to low-frequency vibrations. This design may be compared with both dynamical decoupling methods and decoherence-free subspaces that are described in quantum information processing. By removing the need for bulky vibration isolation setups, this design will make it easier to adopt neutron interferometry to a wide range of applications and increase its sensitivity.

2009-05-01

266

Computer-mediated infertility support groups: An exploratory study of online experiences  

British Library Electronic Table of Contents (United Kingdom)

Objective Over recent years the Internet has become an increasingly popular source of support and information for infertility, with a growing number of online support groups now available to individuals affected by fertility problems. The aims of the present study were therefore to explore the online experiences of individuals accessing infertility support groups via the Internet. Methods Ninety-five participants who were recruited from several online infertility support groups completed an online questionnaire containing a series of open-ended questions. Responses to the open-ended questions were analysed using inductive thematic analysis. Results The thematic analysis revealed five recurrent themes, which were labelled: `unique features of online social support', `improved relationship w...

2008-01-01

267

Competitive and allelopathic interference between soybean crop and annual wormwood (Artemisia annua L.) under field conditions  

British Library Electronic Table of Contents (United Kingdom)

Annual wormwood interference on soybean crop growth and yield may result from competition and allelopathy, which are modulated by crop management. Allelochemicals released by annual wormwood (e.g. artemisinin) may affect the crop directly or indirectly through the effect on the nitrogen fixing symbiont, Bradyrhizobium japonicum. The objectives were (i) to quantify the crop response (i.e. biomass production, nodulation and yield) to weed interference and (ii) to determinate the relative change of competition and allelopathy interferences, when a sublethal dose of herbicide is applied. Two split plot field experiments with three replications were used. The experiment involved a factorial combination of five weed-crop density (soybean/annual wormwood, plantsm^-^2) levels: D1, pure soybean, 40...

2011-01-01

268

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.

269

A study on the pretreatment of a sugarcane bagasse sample with dilute sulfuric acid  

British Library Electronic Table of Contents (United Kingdom)

Experiments based on a 23 central composite full factorial design were carried out in 200-ml stainless-steel containers to study the pretreatment, with dilute sulfuric acid, of a sugarcane bagasse sample obtained from a local sugar?alcohol mill. The independent variables selected for study were temperature, varied from 112.5?C to 157.5?C, residence time, varied from 5.0 to 35.0 min, and sulfuric acid concentration, varied from 0.0% to 3.0% (w/v). Bagasse loading of 15% (w/w) was used in all experiments. Statistical analysis of the experimental results showed that all three independent variables significantly influenced the response variables, namely the bagasse solubilization, efficiency of xylose recovery in the hemicellulosic hydrolysate, efficiency of cellulose enzymatic saccharificatio...

2011-01-01

270

A study on effects of parameters in the Lagrangian code based on F.E.M. through oblique dual-plates perforation phenomena  

International Nuclear Information System (INIS)

This study is concerned to the perforation phenomena of the oblique dual-plate by projectile. Experiment and simulation related to that was carried out. the variables considered in this phenomena include the electrolytic zinc coated steel sheet and carbon steel rod. In the former, the confirmation and projectile velocity possible phenomena of real phenomena is done, the latter, the effect of parameter such as time-step and grid space length is analyzed by using the three-dimensional Lagrangian explicit time-integration finite element code, HEMP. This code use the eight node hexahedral elements and in this study, Von-Mises Criteria is used as the strength model, Mie-Gruneisen is as the Equation of State. The simulation was performed by contrast with the experiment. Through the calibration of the parameter of Lagrangian code, reasonable result was approached.

2004-11-03

271

A partnership approach to service needs assessment with family caregivers of an aging relative living at home: A qualitative analysis of the experiences of caregivers and practitioners  

British Library Electronic Table of Contents (United Kingdom)

Background: As the global population ages, support for family caregivers who provide the bulk of care to community-dwelling older people is becoming ever more important. However, in many countries, homecare-service practitioners currently do not follow a systematic approach to assessing and responding to caregiver needs. Objectives: The aim of this study was to explore the experiences of caregivers and practitioners who took part in a field test of the Family Caregivers Support Agreement (FCSA) tool, a modified version of the Carers Outcome Agreement Tool (COAT) initially developed as the result of an Anglo-Swedish study. Both the COAT and the FCSA are designed to facilitate partnerships between caregivers and practitioners so that needs assessment and subsequent support services are negot...

2010-01-01

272

A numerical investigation of scale-up effects on coke yields of a thermal cracking Riser reactor  

Energy Technology Data Exchange (ETDEWEB)

A validated computational fluid dynamics (CFD) computer code, ICRKFLO, was used to investigate the scale-up effects on the coke yields of thermal cracking riser factors. Comparisons were made for calculated coke yields of pilot- and commercial-scales riser units. Computational results show that the riser aspect ratio, reaction temperature, particle residence time, and particle/oil ratio have major impacts on the coke yield. A computational experiment was conducted to determine optimal operating conditions for a conceptual design of a commercial-scale riser unit. This experiment showed that the performance loss in scale-up from pilot to commercial scale may be almost completely recovered through optimizing the operating conditions after scale-up using the CFD simulations as a guide.

1995-05-01

273

A beam funnelling demonstration: Experiment and simulation  

Energy Technology Data Exchange (ETDEWEB)

Accelerator concepts for heavy-ion fusion require small emittance, high-current beams. Such applications could include funnels in which high-current, like-charged particle beams are interlaced to double beam current while retaining small emittances. The first experimental demonstration confirming the beam dynamics of the funnel principle was recently completed at Los Alamos National Laboratory. A single-leg prototype 5-MeV, H{sup {minus}} funnel was successfully tested. This single-beam demonstration explored physics issues of a two-beam funnel. It contained elements for emittance control, position control, and rf deflection, as well as diagnostics for measurement of beam intensity, position and angle centroids, energy and phase centroids, and transverse and longitudinal phase-space distributions. Results of the experiment will be presented along with comparisons to simulations. 7 refs., 5 figs.

1990-01-01

274

A VUV prism spectrometer for RICH radiator refractometry  

CERN Document Server

A prism spectrometer has been developed to operate in the VUV wavelength range from 120 to 200 nm. It can be used as a pre- disperser in conjunction with a Fabry-Perot based gas refractometer. This instrument has also been used to measure the refractive index of the liquid radiator C/sub 6/F/sub 14/ in various spectral lines. This radiator is used in the RICH detectors of the DELPHI experiment and has been proposed for ALICE, and LHCb experiments. The spectral resolution of the system is improved as the wavelength decreases and the data are consistent with a wavelength accuracy about 0.4 nm at 140 nm. The results for the dispersion curve of the above liquid are presented. (17 refs).

2000-01-01

275

/sup 252/Cf-source-driven neutron noise measurements of subcriticality for a slab tank containing aqueous Pu-U nitrate  

Energy Technology Data Exchange (ETDEWEB)

In order to study nuclear criticality safety related to the development of fast breeder technology, /sup 252/Cf-source-driven neutron noise analysis measurements were performed with a Pu-U nitrate solution in a slab tank of various heights and thickness varying 11.43 cm to 19.05 cm. The results and conclusions of these experiments are (1) a capability to measure the subcriticality of a multiplying system of slab geometry to a k/sub eff/ as low as 0.7 was demonstrated, (2) calculated neutron multiplication factors agreed with those from the experiments within approx.0.02, and (3) the applicability of the method for plutonium solution systems was demonstrated. This paper describes measurements in which the height of the slab was varied for a fixed thickness and the thickness varied for a fixed height, which are the first applications of this measurement method to slab geometry.

1987-08-01

277

CERN's 'Big Bang' experiment given green light  

CERN Document Server

CERN's 'Big Bang' experiment given green light

2008-01-01

278

Big Bang experiment given green light  

CERN Document Server

Big Bang experiment given green light

2008-01-01

279

Numerical analysis and visualization experiment on behavior of borated water during MSLB with RCP running mode in an advanced reactor  

Energy Technology Data Exchange (ETDEWEB)

The core bypass phenomenon of borated water injected through direct vessel injection (DVI) nozzles in APR1400 (Advanced Power Reactor 1400MWe) during main steam line break (MSLB) accidents with a reactor coolant pump (RCP) running mode has been simulated using a two-channel and one-dimensional system analysis model code (MARS), and a three-dimensional computational fluid dynamics (CFD) code (FLUENT). A visualization experiment has also been performed using a scaled-down model of the APR1400. The MARS analysis has predicted a serious core bypass phenomenon of borated water, while the CFD analysis has shown results opposite to the MARS results. The CFD analysis has shown that the flow pattern in the downcomer is fully three-dimensional and that vortex flow structures are formed near the cold legs so that the borated water might pass without difficulty into the high flow region of the cold legs and flow well into the lower ...

2007-04-15

280

Approaches to Modeling Coupled Flow and Reaction in a 2-D Cementation Experiment  

Energy Technology Data Exchange (ETDEWEB)

Porosity evolution at reactive interfaces is a key process that governs the evolution and performances of many engineered systems that have important applications in earth and environmental sciences. This is the case, for example, at the interface between cement structures and clays in deep geological nuclear waste disposals. Although in a different transport regime, similar questions arise for permeable reactive barriers used for biogeochemical remediation in surface environments. The COMEDIE project aims at investigating the coupling between transport, hydrodynamics and chemistry when significant variations of porosity occur. The present work focuses on a numerical benchmark used as a design exercise for the future COMEDIE-2D experiment. The use of reactive transport simulation tools like Hytec and Crunch provides predictions of the physico-chemical evolutions that are expected during the future experiments in laboratory. Focus is given in ...

2008-04-01

281

The Need for Confirmatory Experiments on the Radioactive Source Term from Potential Sabotage of Spent Nuclear Fuel Casks  

Science.gov (United States)

A technical review is presented of experiment activities and state of knowledge on air-borne, radiation source terms resulting from explosive sabotage attacks on spent reactor fuel subassemblies in shielded casks. Current assumptions about the behavior of irradiated fuel are largely based on a limited number of experimental results involving unirradiated, depleted uranium dioxide ''surrogate'' fuel. The behavior of irradiated nuclear fuel subjected to explosive conditions could be different from the behavior of the surrogate fuel, depending on the assumptions made by the evaluator. Available data indicate that these potential differences could result in errors, and possible orders-of-magnitude overestimates of aerosol dispersion and potential health effects from sabotage attacks. Furthermore, it is suggested that the current assumptions used in arriving at existing ...

2002-04-01

282

Technical data analysis program. Final report. [Fort Lewis and P-99; data consolidation  

Science.gov (United States)

Separate comprehensive final reports on the status of the SRC-II Demonstration Plant Design and on operating experiences at the Ft. Lewis and P-99 SRC pilot plants were prepared after the termination of those projects. However, time constraints made it impossible to consolidate all of the pilot plant data and operating experiences and relate these to the Demonstration Plant or future plant design. Most of the experimental programs during the later stages of pilot plant operation were in direct support of specific technical uncertainties identified in design work. The results of these programs would have been of substantial use in verifying or modifying design philosophy had the project proceeded. This technical data analysis project was undertaken to consolidate the pilot plant results presented in numerous reports under DOE Contract DE-AC01-79ET10104 for operation of the pilot plants, and to relate ...

1984-11-01

283

Radiation-induced mutations at mouse hemoglobin loci  

International Nuclear Information System (INIS)

In experiments designed to detect new mutations affecting hemoglobin, we irradiated the male or female parent in reciprocal crosses of two mouse strains that differ in alleles at the hemoglobin (Hba, Hbb) loci as well as at five other specific loci. Offspring were analyzed for hemoglobin properties (electrophoretic pattern, solubility, crystal pattern), serum albumin differences, erythrocyte lysis, reticulocyte count, and external appearance. Five hemoglobin variants were found among the mutants. In three, the genetic contribution from the irradiated father was not expressed with regard to the #alpha#-chain; one carried a tandem duplication (the first known case in the mouse) involving Hbb; and one probably resulted from double nondisjunction of chromosome 7. The finding that major chromosome aberratios can mimic hemoglobin mutations indicates the need, in similar experiments, to follow F_1 screening with thorough ...

284

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

Energy Technology Data Exchange (ETDEWEB)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K{sup Iscc}, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, ...

2002-07-01

285

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

International Nuclear Information System (INIS)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K"I"s"c"c, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, ...

2002-05-05

286

Development of advanced residential cooktop burner with low NO/sub x/ emissions. Annual report Feb 82-Jan 83  

Science.gov (United States)

This report describes the results of work conducted during February 1982 - January 1983. A literature search was initiated to identify the state-of-the-art of NOx (NO + NO/sub 2/) reduction technologies, including NOx measurement methodologies, air infiltration and ventilation trends, the impact of NOx (NO/sub 2/) emissions on health, and air quality standards. As a result of the literature search NOx (NO/sub 2/) reduction goals were established for the project and technologies to achieve these goals identified. This report also covers the development of a prototype burner which examined flue gas recirculation, burner designs, secondary air baffling and flame inserts as potential technologies to reduce NOx (NO/sub 2/). Because of their potential for NOx (NO/sub 2/) reduction shown by initial experiments, an in-depth analysis of ring insert configurations was conducted. These results, along with other ...

1983-02-28

287

Comparisons between experimental results and numerical simulations for the Sonaco sodium natural convection experiments  

International Nuclear Information System (INIS)

The SONACO experiments are conducted on an electrically heated 37-pin rod bundle, immersed in liquid sodium and contained within a hexagonal wrapper. The rig was designed to investigate natural convection cooling for a geometry representative of fast reactor fuel assemblies. Heat can be removed from the test section in several ways, but in this paper only the axial cooling mode is examined. Above the heated bundle is a plenum, at the top of which is a cooling coil containing a separate, forced sodium flow. Heat transfer from the bundle to this cooling coil is effected by means of buoyancy driven circulatory flow in the sodium, and in the axial cooling mode almost all the heat is removed by the coil. This mode is intended to simulate the natural convection cooling of a blocked fuel assembly by way of thermosyphon coupling to the inner pool. In this paper experimental results are presented, for the temperatures measured under such conditions, and ...

288

Benchmark problem: Hydraulics and heat transfer in the model pin bundle with liquid metal coolant. UPV-EHU calculations  

International Nuclear Information System (INIS)

The Department of Nuclear Engineering and Fluid Mechanics in the University of the Basque Country (UPV-EHU), has done calculations for the proposed benchmark problem, in the frame of the 11th international meeting of the IAHR working group on advanced nuclear reactors thermal-hydraulics (Obninsk-Russian Federation, 5-9 July 2004). The purpose of the benchmark is to compare experimental and analytical results of some experiments carried out in the State Scientific Center of Russian Federation 'Institute of Physics and Power Engineering' (SSC RF IPPE). These experiments were held to research the cooling of pin bundles by liquid metals in reference to the core of Nuclear Reactors such as BREST. The analytical results have been done with the Computational Fluid Dynamics (CFD) code FLUENT. Temperature and velocity fields are the main variables considered for the comparison, and some assumptions has been made ...

2004-07-05

289

Basic models and verification study on fuel rod heat-up and fission product release analysis modules in SAMPSON for the IMPACT project  

International Nuclear Information System (INIS)

The super simulator 'SAMPSON' has been developed to show that there exist certain safety margins for light water reactors under hypothetical severe accidents and to investigate realistic measures of accident management by simulating accidents with a parallel computer. Heat-up of fuel rods and release of fission products from fuels are important factors to evaluate source terms. Models for fuel rod heat-up, hydrogen production due to cladding oxidation and cladding deformation and failure in the core region have been developed in the fuel rod heat-up analysis module. Fuel temperatures were calculated by solving the heat conduction equation. The calculated results for fuel temperature and hydrogen production were compared with CORA-13 experiment results. The comparisons showed prediction capability for the heat-up of fuel rods. The fission product release analysis module incorporates with models for fission product transport ...

1999-04-19

290

Verification of a nuclear analysis system for fast reactors using BFS-62 critical experiment  

International Nuclear Information System (INIS)

Critical experiments have been analyzed to verify a nuclear analysis system for fast reactors used in Japan Nuclear Cycle Development Institute (JNC). The experiments were performed in a collaboration work between JNC and the Institute of Physics and Power Engineering of Russia to dispose Russian surplus weapons plutonium, focusing on the effect of the introduction of uranium-plutonium mixed-dioxide (MOX) fuel and stainless steel reflector into the current BN-600 core that is comprised of UO_2 fuel and blanket. The analysis results agreed well with measured values on most of the nuclear characteristics. The accuracies are comparable to those obtained for the conventional MOX fueled fast reactors. It suggests that the JNC analysis system can analyze accurately nuclear characteristics in uranium fueled cores as well. A significant improvement was achieved on the sodium void reactivity by employing an ultra fine group cell ...

2004-12-01

291

Treatment of waste rock piles at Wood Cadillac using a reducing trickling filter; Traitement des resurgences du parc a residus miniers Wood Cadillac au moyen d'un biofiltre reducteur  

Energy Technology Data Exchange (ETDEWEB)

The Ministere des Ressources naturelles du Quebec (Quebec Natural Resources Department) implemented a remedial program to treat the waste rock pile at Wood Cadillac, located near Cadillac, in Abitibi, Quebec. The solutions proposed by INRS-Georessources and ENVIROCONSEIL are aimed at eliminating erosion and stabilizing the geochemical processes. Part of the proposed solution also included the use of a reducing trickling filter for the treatment of acid leachates, which also contain arsenic when exiting the waste rock pile. The trickling filter is composed of forest tailings in which the bacteria reduce the sulphates and stimulate the precipitation of arsenic into arsenic sulphates. This is a new treatment that was developed following laboratory experiments which demonstrated the feasibility of the process and quantified the parameters. A demonstration unit was constructed by ENVIROCONSEIL and installed at the Wood Cadillac waste rock pile under the supervision of ...

2000-07-01

292

Studies of the applicability of opto-electronic devices for instrumentation in high-energy physics. Progress report, June 1, 1981-May 31, 1982  

Energy Technology Data Exchange (ETDEWEB)

Instrumentation research to study the feasibility of using optical data processing techniques to solve real-time pattern recognition problems for high energy physics experiments is now in its second year. During the past year, a prototype optical processor for use in BNL Experiment 702 was conceived and designed, using test data from the experiment and simulating the optical processor in the computer. A number of technical studies have been made, mostly relating to the selection of the optical filter for the processor. Comparisons between natural and synthetic holograms, both bleached and unbleached, have been made. We conclude from these tests that the kinoform, a computer-generated phase hologram, is the optimal choice for this processor. A new method for producing the kinoform has been tried by this group with encouraging results. The optical design for the prototype processor is complete, and the ...

1982-01-01

293

Results of Compact Stellarator Engineering Trade Studies  

Energy Technology Data Exchange (ETDEWEB)

number of technical requirements and performance criteria can drive stellarator costs, e.g., tight tolerances, accurate coil positioning, low aspect ratio (compactness), choice of assembly strategy, metrology, and complexity of the stellarator coil geometry. With the completion of a seven-year design and construction effort of the National Compact Stellarator Experiment (NCSX) it is useful to interject the NCSX experience along with the collective experiences of the NCSX stellarator community to improving the stellarator configuration. Can improvements in maintenance be achieved by altering the stellarator magnet configuration with changes in the coil shape or with the combination of trim coils? Can a mechanical configuration be identified that incorporates a partial set of shaped fixed stellarator coils along with some removable coil set to enhance the overall machine maintenance? Are there other approaches that will ...

2009-05-27

294

Results of Compact Stellarator Eengineering Trade Studies  

Energy Technology Data Exchange (ETDEWEB)

A number of technical requirements and performance criteria can drive stellarator costs, e.g., tight tolerances, accurate coil positioning, low aspect ratio (compactness), choice of assembly strategy, metrology, and complexity of the stellarator coil geometry. With the completion of a seven-year design and construction effort of the National Compact Stellarator Experiment (NCSX) it is useful to interject the NCSX experience along with the collective experiences of the NCSX stellarator community to improving the stellarator configuration. Can improvements in maintenance be achieved by altering the stellarator magnet configuration with changes in the coil shape or with the combination of trim coils? Can a mechanical configuration be identified that incorporates a partial set of shaped fixed stellarator coils along with some removable coil set to enhance the overall machine maintenance? Are there other approaches that will ...

2009-09-25

295

Reflood experiments with simultaneous upper and lower plenum injection in the REWET-II rod bundle facility  

International Nuclear Information System (INIS)

A series of 27 reflood experiments has been carried out in a full-length electrically heated rod bundle facility. The primary objective of these tests was to study the effects of a simultaneous upper plenum and downcomer coolant injection and to provide data for the verification of computer codes. The experimental results indicate that an upper plenum injection alone cools the test rods slowly, a simultaneous coolant injection to the downcomer improves cooling significantly, and a downcomer injection alone cools the test rod bundle best if the total value of the coolant flow rate is the same in these three different cases. If the coolant injected to the upper plenum increases the total flow rate, the quench time of the test rods decreases at all elevations. Quenching time and clad temperature histories calculated with the computer codes NORCOOL-I and FLOOD4 are in a reasonable quantitative agreement with experiments in the ...

1983-02-01

296

Reduced exposure to microwave radiation by rats: frequency specific effects  

Energy Technology Data Exchange (ETDEWEB)

Previous research has shown that SAR hotspots are induced within the laboratory rat and that the resulting thermal hotspots are not entirely dissipated by bloodflow. Two experiments were conducted to determine if hotspot formation in the body and tail of the rat, which is radiation frequency specific, would have behavioral consequences. In the first experiment rats were placed in a plexiglas cage one side of which, when occupied by the rat, commenced microwave radiation exposure; occupancy of the other side terminated exposure. Groups of rats were tested during a baseline period to determine the naturally preferred side of the cage. Subsequent exposure to 360-MHz, 700-MHz or 2450-MHz microwave radiation was made contingent on preferred-side occupancy. A significant reduction in occupancy of the preferred side of the cage, and hence, microwaves subsequently occurred. Reduced exposure to 360-MHz and 2450-MHz microwaves at 1, ...

1988-01-01

297

Photovoltaic solar power in building engineering. Experience feedback in France of the European Hip Hip project. Advances and realizations; L'electricite solaire photovoltaique dans le batiment. Retour d'experience en France du Projet Europeen Hip Hip. Avancees et realisations  

Energy Technology Data Exchange (ETDEWEB)

The European demonstration project Hip Hip (house integrated photovoltaic high-tech in public) led the French photovoltaic market to reach a level comparable to those of the other European countries in terms of relevance of implemented solutions and costs. This document presents the best realizations and the experience gained through the Hip Hip project. Its aim is to convince the designers and managers of building projects of the advantages of photovoltaic installations integrated to the structure and connected to the power distribution grid: 1 - presentation of the technology; 2 - status of the Hip Hip demonstration project (goals, results: main innovations and impact on the French market); 3 - different possibilities of integration to the building structure; 4 - examples of projects realized in France in the framework of the Hip Hip project: integration in glass roof, frontage, added elements, fitting on roofs. (J.S.)

2003-07-01

298

Performance of the AMS-02 Experiment for High Energy Gamma Ray Astrophysics  

CERN Document Server

AMS is a particle detector designed to perform high precision measurements of the cosmic rays fluxes with the main goals of searching for anti-nuclei, as remnants of primordial anti-matter, and of measuring the faintest components of the cosmic flux, anti- protons, positrons and high energy photons. To fulfill the requirements of large acceptance, long exposure time and excellent particle identification needed to achieve the intended results, AMS will operate in space as an attached payload to the International Space Station (ISS), being the first full featured particle physics experiment to operate in the Earth orbit. The AMS-02 accurate measurements of cosmic-ray nuclei, protons, antiprotons, electrons and positrons will be completed by high energy gamma rays detection. The experiment will detect gamma-rays, either by reconstructing e+e? pairs generated by photons converted upstream the tracker (conversion mode), or based ...

2007-01-01

299

Influence of excited molecules on electron swarm transport coefficients and gas discharge kinetics  

Energy Technology Data Exchange (ETDEWEB)

In this paper we study different effects of excited molecules on swarm parameters, electron energy distribution functions and gas discharge modeling. First we discuss a possible experiment in parahydrogen to resolve the discrepancy in hydrogen vibrational excitation cross section data. Negative differential conductivity (NDC) is a kinetic phenomenon which manifests itself in a particular dependence of the drift velocity on E=N and it is affected by superelastic collisions with excited states. A complete kinetic scheme for argon required to model excited state densities in gas discharges is also described. These results are used to explain experiments in capacitively and inductively coupled RF plasmas used for processing. The paper illustrates the application of atomic and molecular collision data, swarm data and the theoretical techniques in modeling of gas discharges with large abundances of excited molecules. It is ...

1997-09-01

300

Identifying primary stressors impacting macroinvertebrates in the Salinas River (California, USA): Relative effects of pesticides and suspended particles  

International Nuclear Information System (INIS)

Laboratory dose-response experiments with organophosphate and pyrethroid pesticides, and dose-response experiments with increasing particle loads were used to determine which of these stressors were likely responsible for the toxicity and macroinvertebrate impacts previously observed in the Salinas River. Experiments were conducted with the amphipod Hyalella azteca, the baetid mayfly Procloeon sp., and the midge Chironomus dilutus (Shobanov, formerly Chironomus tentans). The results indicate the primary stressor impacting H. azteca was pesticides, including chlorpyrifos and permethrin. The mayfly Procloeon sp. was sensitive to chlorpyrifos and permethrin within the range of concentrations of these pesticides measured in the river. Chironomus dilutus were sensitive to chlorpyrifos within the ranges of concentrations measured in the river. None of the species tested were affected by turbidity as high as ...

2006-06-01

301

Experiment for 3-component S-wave reflection survey. Part 3; Sanseibun S ha hanshaho no kiso jikken. 3  

Energy Technology Data Exchange (ETDEWEB)

Anisotropy has been investigated using S-wave as a technique for detecting fractures. In this study, fundamental experiments were carried out with slightly changing the measuring conditions at a place where anisotropy was expected. This paper describes the fundamental data acquisition of anisotropy analysis using S-wave, and a part of the results. The experiments were conducted on the agricultural road in Yamadera district, Matsuyama-machi, Yamagata Prefecture. Two flat unpaved roads meeting at right angles were used as traverse lines. In this place, several reflection surfaces were certainly detected by P-wave, and anisotropy of S-wave was confirmed from the velocity of refracted wave of S-wave. Data were processed for individual traverse lines meeting at right angles. Firstly, signal sweeping, correlation, and vertical superposition were made. Six kinds of data were prepared, i.e., three-component receiving records of ...

1996-10-01

302

Effective multiplication factor measurement by feynman-{alpha} method. 3  

Energy Technology Data Exchange (ETDEWEB)

The sub-criticality monitoring system has been developed for criticality safety control in nuclear fuel handling plants. In the past experiments performed with the Deuterium Critical Assembly (DCA), it was confirmed that the detection of sub-criticality was possible to k{sub eff} = 0.3. To investigate the applicability of the method to more generalized system, experiments were performed in the light-water-moderated system of the modified DCA core. From these experiments, it was confirmed that the prompt decay constant ({alpha}), which was a index of the sub-criticality, was detected between k{sub eff} = 0.623 and k{sub eff} = 0.870 and the difference of 0.05 - 0.1{Delta}k could be distinguished. The {alpha} values were numerically calculated with 2D transport code TWODANT and monte carlo code KENO V.a, and the results were compared with the measured values. The differences between calculated and ...

1998-06-01

303

Determination of reactivity from power spectral density measurements with /sup 252/Cf. [LMFBR  

Science.gov (United States)

The theory of a method of determination of reactivity from power spectral density measurements with /sup 252/Cf and the results of experiments with a critical assembly mockup of a liquid-metal fast breeder reactor (LMFBR) and with uranium (93.2 wt % /sup 235/U) metal cylinders and a sphere are presented. This method of reactivity determination has an advantage over existing methods in that it determines the reactivity only from properties of the reactor at the subcritical state of interest and thus does not require a calibration near delayed criticality. In these experiments, the reactivity was varied by changing the fissile loading or the amount of neutron absorber inserted; for the LMFBR mockup, the reactivity varied to approximately 75 dollars subcritical, and for the uranium metal assemblies to approximately 30 dollars subcritical. These experiments verified for the first time the predictions of ...

1978-04-01

304

Central Cross-Talk in Task Switching : Evidence from Manipulating Input-Output Modality Compatibility  

Science.gov (United States)

Two experiments examined the role of compatibility of input and output (I-O) modality mappings in task switching. We define I-O modality compatibility in terms of similarity of stimulus modality and modality of response-related sensory consequences. Experiment 1 included switching between 2 compatible tasks (auditory-vocal vs. visual-manual) and between 2 incompatible tasks (auditory-manual vs. visual-vocal). The resulting switch costs were smaller in compatible tasks compared to incompatible tasks. Experiment 2 manipulated the response-stimulus interval (RSI) to examine the time course of the compatibility effect. The effect on switch costs was confirmed with short RSI, but the effect was diminished with long RSI. Together, the data suggest that task sets are modality specific. Reduced switch costs in compatible tasks may be due to special linkages between input and output modalities, whereas ...

2010-07-01

305

A habitat template approach to green building surfaces  

Energy Technology Data Exchange (ETDEWEB)

The use of entire plant communities of native species is gaining interest in the green roof industry. Plant communities must be matched with environmental conditions that mimic conditions in their original habitats. Urban built environments do not differ significantly from the rocky outcrops with poor, shallow soil that many plants colonize. This paper provided details of an experiment investigating the impact of plant community structure and species diversity on living roof performance. The aim of the experiment was to determine the impact of species diversity on precipitation interception, nutrient retention, temporal biomass constancy and roof temperature constancy. The diversity treatment included separate monocultures of 8 species in the community, randomly determined mixtures of 4 species, and a mixture of all 8. Functional groups included mosses, liverworts, colonial algae and a mycorrhizal inoculum. In a second ...

2005-07-01

306

The importance of an accurate target wave function in variational calculations for (e^{+}-H_{2}) scattering  

CERN Document Server

Using the complex Kohn method, we have calculated variational values of phase shifts and the annihilation parameter, Z_{eff}, for the elastic scattering of positrons by molecular hydrogen. Our results are sensitive to small changes in the accuracy of the wave function representing the target hydrogen molecule. We have developed a systematic approach to demonstrate that, at low positron energies, there are particular forms of the Kohn trial wave function for which the results of variational calculations are not reliable, even when the target wave function accounts for as much as 96.8% of the correlation energy of H_{2}. We find that reliable results can be recovered if our calculations are extended to admit more sophisticated target wave functions accounting for 99.7% of the correlation energy. Remaining discrepancies between theory and experiment are briefly discussed.

2008-01-01

307

Status of the surry low power and shutdown PRA  

International Nuclear Information System (INIS)

The Surry low power and shutdown probabilistic risk analysis (PRA) is an ongoing project at Brookhaven National Laboratory (BNL) to identify and quantify potential accident scenarios that may occur in a pressurized water reactor (PWR) during low power and shutdown. It was initiated as a result of various incidents and accidents that have occurred within the United States and overseas. The project involves review and evaluation of PWR experience at shutdown, identification of accident scenarios, determination of methods to mitigate the accidents, and performance a level 1 PRA. An evaluation of accident progression, source terms and consequences has also been initiated. The results will be used to address issues related to shutdown conditions. The objective of this paper is to provide a progress report on the project, and to present the approach used as well as the preliminary results of the ongoing and ...

1991-04-01

308

Photoacoustic imaging using an ultrasonic Fresnel zone plate transducer  

International Nuclear Information System (INIS)

A photoacoustic (PA) imaging system based on an ultrasonic Fresnel zone plate (FZP) transducer is developed for the purpose of imaging biological tissue. This FZP transducer has a two-zone negative zone plate piezoelectric material pattern, and an optical fibre is integrated with the transducer on the symmetric axis of the zone plates to deliver laser pulses to the sample. The focal characteristic of the FZP transducer is analysed by theoretical prediction and experimental measurement, and the measured results are in good agreement with the predicted results. The limited-field back-projection deconvolution algorithm combined with the coherence-factor weighting technique is used to reconstruct the optical absorption distribution. The experiments were performed with phantoms and the blood vessels of chicken embryo chorioallantoic membrane. The results demonstrate that PA imaging using the FZP transducer ...

2008-05-07

309

Materials Research Related to W-band Cavity Construction  

Energy Technology Data Exchange (ETDEWEB)

Low power rf measurements, S11, of electro-discharge machined (EDM) diffusion bonded mm-wave traveling wave rf cavities were not in satisfactory agreement with electromagnetic simulations. During subsequent mechanical inspection, the cell-to-cell iris were found to be distorted. This led to a series of systematic experiments to study the mechanical properties of oxygen free high conductivity Copper (OFHC) and Glidcop AL-15. Results of these studies which include cell-to-cell iris distortion, EDM machining accuracies, surface quality, and the results of different bonding techniques are presented. The results of our mechanical studies are used to develop a set of mechanical design constraints for a second series of constant impedance W-Band structures that also used wire EDM and high temperature bonding for their manufacture.

2000-10-18

310

Language and Music in the Musician Brain  

British Library Electronic Table of Contents (United Kingdom)

Abstract Results of numerous experiments conducted over the past 15-years by using behavioural as well as brain imaging methods have shown that musical expertise influences brain anatomy, brain functions and behaviour. The musician- brain is thus considered as a very good model of brain plasticity. Moreover, many results have demonstrated that musical expertise not only impacts on music processing but also on several aspects of speech processing including lexical pitch, sentence intonation and the metric structure of words. Conversely, recent results indicated that linguistic expertise with tone or quantity languages such as Mandarin Chinese, Thai, Finnish and Japanese, influences the processing of harmonic tones and musical intervals. We discuss possible interpretations of these findings ...

2011-01-01

311

Experimental modelling of thermal consolidation effects around a high level waste repository  

International Nuclear Information System (INIS)

This report summarizes the results of a research programme which involves the development of a laboratory experimental facility for the simulation and study of hydro-thermo-mechanical processes in saturated geomaterials with low permeability. The experimentation involves a synthetic cement based porous material made of cement grout which possesses permeabilities in the range of dense unfractured sandstones or shale. Specially manufactured pore-pressure transducers were installed within the cylindrical block at locations adjacent to a plane free boundary. The block was saturated with the periodic application of a vacuum. In its saturated state the plane boundary of the block was subjected to heating via a circular heater the temperature of which was maintained constant. The resulting pore pressure generation along with temperature at these locations was monitored continuously. The results of a series of ...

312

Electromagnetic dissociation of 200 GeV/nucleon sup 16 O and sup 32 S ions in nuclear emulsions  

Energy Technology Data Exchange (ETDEWEB)

This work represents the results of an experimental investigation of the electromagnetic dissociation of 200 GeV/nucleon {sup 16}O and {sup 32}S ions in nuclear emulsions. Exclusive channels involving charged fragments have been studied as a function of the energy released and, assuming a Weizsaecker-Williams spectrum of virtual photons, there is a good agreement with results for the ({gamma}, p) processes obtained with real photons. However, the rates found for other processes are larger, in particular for the ({gamma}, {alpha}) on both nuclei. The values of the total integrated absorption cross sections are generally larger than those obtained from real photon experiments but the extent of the discrepancy depends strongly upon which photon results are used in the comparison. (orig.).

1990-10-08

313

Combined migration velocity model-building and its application in tunnel seismic prediction  

Science.gov (United States)

We propose a combined migration velocity analysis and imaging method based on Kirchhoff integral migration and reverse time migration, using the residual curvature analysis and layer stripping strategy to build the velocity model. This method improves the image resolution of Kirchhoff integral migration and reduces the computations of the reverse time migration. It combines the advantages of efficiency and accuracy of the two migration methods. Its application in tunnel seismic prediction shows good results. Numerical experiments show that the imaging results of reverse time migration are better than the imaging results of Kirchhoff integral migration in many aspects of tunnel prediction. Field data show that this method has efficient computations and can establish a reasonable velocity model and a high quality imaging section. Combination with geological information can make an accurate prediction of ...

2010-09-01

314

Experiments in High-Frequency Imaging of the 2004 M6.0 Parkfield Earthquake  

Science.gov (United States)

We attempt to image the rupture propagation of the 2004 M6.0 Parkfield earthquake by analyzing records from the USGS Parkfield seismic array (UPSAR) and other strong-motion stations. The UPSAR array consists of 12 stations distributed over about one square kilometer at a distance of 10~km from the San Andreas fault near Parkfield, California. We employ a method that uses reverse time migration to stack the seismograms at back-projected locations along the fault. We use waveform cross-correlation to align the initial P-wave arrivals and correct for small static time shifts in the records. This forces a coherent image at the hypocenter at the quake origin time. Initial results at later time steps show some evidence of the expected rupture propagation to the north. However, the resolution of the back-projection is limited by the small aperture of the UPSAR array. Records from other strong-motion stations can improve the theoretical resolution kernels but are less ...

2006-12-01

315

Optical second-harmonic generation in III-V semiconductors: Detailed formulation and computational results  

Science.gov (United States)

In an earlier paper (Phys. Rev. Lett. 66, 41 (1991)), we calculated both the dielectric constant ({epsilon}{sub {infinity}}) and the nonlinear optical susceptibilities for second-harmonic generation ({chi}{sup (2)}) in the static limit for AlP, AlAs, GaP, and GaAs in the local-density approximation with and without a self-energy correction in the form of a scissors operator,'' including local-field effects. In this paper, we expand our presentation of this calculation. Agreement with experiment to within 15% for the nonlinear susceptibility is demonstrated where experiments are available (GaP and GaAs); the dielectric constants are in no worse than 4% agreement with experiment. The virtual hole'' contributions are reformulated to avoid large numerical cancellations in the case of near degeneracies. The virtual electron'' terms dominate over the virtual ...

1991-12-15

316

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

Energy Technology Data Exchange (ETDEWEB)

Large scale experiments were performed to determine the effectiveness of thermal glow plug igniters to burn hydrogen in a condensing steam environment due to the presence of water sprays. The experiments were designed to determine if a detonation or accelerated flame could occur in a hydrogen-air-steam mixture which was initially nonflammable due to steam dilution but was rendered flammable by rapid steam condensation due to water sprays. Eleven Hydrogen Igniter Tests were conducted in the test vessel. The vessel was instrumented with pressure transducers, thermocouple rakes, gas grab sample bottles, hydrogen microsensors, and cameras. The vessel contained two prototypic engineered systems: (1) a deliberate hydrogen ignition system and (2) a water spray system. Experiments were conducted under conditions scaled to be nearly prototypic of those expected in Advanced Light Water Reactors (such as the Combustion Engineering ...

1997-05-01

317

Combined release of radiation sterilized adults of spotted bollworm, Earias vittella (Fabricius)  

International Nuclear Information System (INIS)

Feasibility of using combined release of sterile males and sterile females for population suppression of Earias vittella (Fabricius) was evaluated on okra in two ways. In one study, a combined release of sterile males and sterile females was evaluated under simulated conditions in laboratory, a 10: 10: 1: 1 (sterile male: sterile female: normal female: normal male) ratio effected > 99% sterility. In the second study, in a field cage experiment, a combined release of sterile males and sterile females was evaluated using normal males and tethered normal females. In this experiment, the release of sterile males and sterile females in 10: 10: 1: 1 ratio caused complete 'shut off' of mating of normal females for first 2 days and indicated>93% reduction in the larval progeny in the next generation. The tethered females were allowed to mate only once. E. vittella females mate multiply and so with overwhelming numbers of sterile males present, ...

2005-06-01

318

Transient analysis of blowdown thrust force under PWR LOCA conditions  

Energy Technology Data Exchange (ETDEWEB)

The analytical results of blowdown characteristics and its thrust force were compared with the experiment, which were performed as pipe whip tests under the PWR LOCA conditions on the hypothetical accident of guillotine break of pipes. The blowdown thrust force was obtained by the integral momentum equation about single-phase flow, homogeneous and separated two-phase flow, assuming critical pressure at the exit if critical flow condition was satisfied. The following results are obtained: (1) The node-junction method is useful for the analysis of water hammer phenomena and of the blowdown thrust force. (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 analysis and experiment is 1.08. (3) The thrust parameter of saturated blowdown has the same one with the value under pressurized ...

1982-09-01

319

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 ...

1983-04-01

320

Research by ESS Division for the Nevada Nuclear Waste Storage Investigations: Progress report, January-June 1985  

Energy Technology Data Exchange (ETDEWEB)

Petrographic research for the Nevada Nuclear Waste Storage Investigations focused on xenolithic variability in the Topopah Spring Member and on variations of clinoptilolite composition at Yucca Mountain. Zeolite and smectite occurrences were considered in terms of their relation to a disturbed zone beneath the potential repository, and mineral stability experiments have produced a new clinoptilolite structure as a result of prolonged heating at low temperature. Limitations were defined on the abundance of erionite and of sulfur. X-ray diffraction studies lead to improved analytical methods. Progress was made in the comparative study of mineralogy in sand ramps and in faults. Geological modeling considered the differences of the diffusion of nonsorbing tracers in vertically and in horizontally fractured rock. Modeling also treated the diffusion of a nonsorbing tracer in devitrified and in zeolitized rock. The results of ...

1987-10-01

321

Radiant flash pyrolysis of biomass as a source of fuels and chemicals  

Energy Technology Data Exchange (ETDEWEB)

Last year a team of US and French scientists using the Odeillo (France) 1MW/sub th/ solar furnace showed concentrated solar radiation to be an effective means for rapidly volatilizing biomass materials. The results of continuing research in the U.S. on radiant flash pyrolysis of biomass as a source of fluid fuels, industrial feedstocks and chemicals are described. Bench scale sources of intense, visible radiant energy have been used to simulate the concentrated solar flux available at the focus of solar towers. Windowed transport reactors are being developed, which act as cavity receivers for the focused radiant energy and provide a means for direct use of the radiation to rapidly pyrolyze the entering biomass. One of these reactors will be operated at the focus of the Georgia Tech 400kW/sub th/ solar furnace next August. Preliminary results from the bench scale reactor experiments, and plans for the Georgia Tech ...

1980-01-01

322

New options for simulating swivel momentum in car door hinges with neural networks. Neue Moeglichkeiten zur Simulation von Schwenkmomenten an Automobiltuerscharnieren mit Neuronalen Netzen  

Energy Technology Data Exchange (ETDEWEB)

The generation of a defined swivel momentum in car door hinges depends on numerous constructional and technical manufacturing parameters. If these parameters and their influence are to be investigated, then in addition to detailed experiments with variations in the parameters, methods are also required which enable the measuring data produced to be assessed in such a way that, in general, the non-linear relationships between initial and target size can be described sufficiently accurately. This paper explains the parameter reduction necessary in the experimental investigation, gives the results of the data assessment with conventional statistical methods and describes in particular the use of artificial neural networks (ANN) to construct so-called 'neuro hinge models' on the basis of the data resulting from the experiments. Parameter variations can be simulated with the hinge models ...

1999-04-01

323

Flash pyrolysis of coal-solvent slurry prepared from the oxidized coal and the coal dissolved in solvent; Ichibu yokaishita sanka kaishitsutan slurry no jinsoku netsubunkai  

Energy Technology Data Exchange (ETDEWEB)

In order to develop a high-efficiency coal pyrolysis method, flash pyrolysis was experimented on slurry prepared by using liquid-phase oxidation reformed coal and a methanol-based solvent mixture. Australian Morwell coal was used for the experiment. The oxidized coal, into which carboxyl groups have been introduced, has the condensation structure relaxed largely, and becomes highly fluid slurry by means of the solvent. Char production can be suppressed by making the oxidation-pretreated coal into slurry, resulting in drastically improved pyrolytic conversion. The slurry was divided into dissolved solution, dried substance, extracted residue, and residual slurry, which were pyrolized independently. The dissolved solution showed very high conversion. Improvement in the conversion is contributed by separating the dissolved substances (coal macromolecules) at molecular levels, coagulating the molecules, suppressing cross-link ...

1996-10-28

324

First plasma experiment on spherical tokamak device UTST  

International Nuclear Information System (INIS)

The UTST (University of Tokyo Spherical Tokamak) device was constructed for the purpose of exploring the formation of ultra-high beta ST (Spherical Tokamak) plasma using the double null plasma merging method. When two plasmas merge together to form a single plasma, magnetic field lines reconnect, and the magnetic field energy is converted to the plasma kinetic energy, increasing the plasma beta. The merging start-up has been demonstrated in the TS-3/4, START and MAST devices using coils inside the vacuum vessel and TS-3 plasma obtained 50% beta. In order to demonstrate the start-up in a more reactor relevant situation, UTST has all poloidal field coils outside the vacuum vessel. The first plasma experiment on the UTST was performed from December, 2007. In the result, the plasma obtained 10 kA by using only outer PF coils and single ST was generated at the lower area (z=-0.3 - -1.0[m]) close to a washer gun. This result ...

2009-04-01

325

Exploring multi-metal biosorption by indigenous metal-hyperresistant Enterobacter sp. J1 using experimental design methodologies  

Energy Technology Data Exchange (ETDEWEB)

A novel experimental design, combining mixture design and response surface methodology (RSM), was developed to investigate the competitive adsorption behavior of lead, copper and cadmium by an indigenous isolate Enterobacter sp. J1 able to tolerate high concentrations of a variety of heavy metals. Using the proposed combinative experimental design, two different experiment designs in a ternary metal biosorption system can be integrated to a succinct experiment and the number of experimental trials was markedly reduced from 38 to 26 by reusing the mutual experimental data. Triangular contour diagrams and triangular three-dimensional surface plots were generated to describe the ternary metal biosorption equilibrium data in mixture design systems. The results show that the preference of metal sorption of Enterobacter sp. J1 decreased in the order of Pb{sup 2+} > Cu{sup 2+} > Cd{sup 2+}. The presence of other ...

2008-05-01

326

Eddy current inspection of superconducting cable during manufacturing  

Energy Technology Data Exchange (ETDEWEB)

The downstream failure of cable during winding, insulating, coil winding, and coil assembly is a significant issue in magnet production. The impact of these failures are costly both financially, and from the time to recover from this downstream failure. The current approach to cabling has been to visually inspect the cable for any gross defects during cabling. To date this has been effective in finding small defects such as crossovers for example, which drastically reduce the mechanical integrity of the strand, and thus the cable itself. But because of the large volume of cable which will be manufactured an automated flaw detection system which can inspect the cable and detect these type of defects will be needed. We have recently done an on-line experiment using an Eddy current system, and specialized Eddy current probes to inspect cable during manufacturing. We will present the results of our inspection demonstrating detection of crossovers, ...

1992-03-01

327

Eddy current inspection of superconducting cable during manufacturing  

International Nuclear Information System (INIS)

The downstream failure of cable during winding, insulating, coil winding, and coil assembly is a significant issue in magnet production. The impact of these failures is costly both financially and because of the time needed to recover from them. The current approach to cabling has been to visually inspect the cable for any gross defects during cabling. To date this has been effective in finding small defects such as crossovers, which drastically reduce the mechanical integrity of the strand and thus of the cable itself. But because of the large volume of cable that will be manufactured, an automated flaw detection system that can inspect the cable and detect these types of defects will be needed. We have recently done an on-line experiment using an Eddy current system and specialized Eddy current probes to inspect cable during manufacturing. We will present the results of our inspection, demonstrating detection of crossovers and cold welds. ...

1992-03-04

328

Does DaYa-Bay Reactor Play an Important Role in Theta_{13} of Lepton Mixing (PMNS) Matrix ?  

CERN Document Server

Reactor neutrinos play an important role in determining parameter theta_{13} in the lepton mixing (PMNS) matrix. Next important step on measuring PMNS matrix could be to build another reactor neutrino experiment in DaYa bay, China, to search the possible oscillations via sin^2 (2theta_{13}) and Delta m^2_{13}. We consider 4 different schemes for positions of three 8-ton detectors of this experiment, and simulate the results with respect to an array of assumed ''true'' values of physics parameters. Using three kinds of analysis method, we suggest a best scheme for DaYa-Bay which is to place a detector 2200m ~ 2500m symmetrically away from two reactors, and to put the other two detectors closer to their corresponding reactors respectively, almost at a 100m \\~ 200m distance. Moreover, with conservative assumption on the experimental technique, we construct series of allowed regions from our simulation ...

2004-01-01

329

Development of radioisotope tracer technology  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to develop the radioisotope tracer technology, which can be used in solving industrial and environmental problems and to build a strong tracer group to support the local industries. In relation to the tracer technology in 1999, experiments to estimate the efficiencies of a sludge digester of a waste water treatment plant and a submerged biological reactor of a dye industry were conducted. As a result, the tracer technology for optimization of facilities related to wastewater treatment has been developed and is believed to contribute to improve their operation efficiency. The quantification of the experimental result was attempted to improve the confidence of tracer technology by ECRIN program which basically uses the MCNP simulation principle. Using thin layer activation technique, wear of tappet shim was estimated. Thin layer surface of a tappet shim was irradiated by proton beam and the ...

2000-04-01

330

Development of PHWR fuel fabrication in Korea  

Energy Technology Data Exchange (ETDEWEB)

Korea Advanced Energy Research Institute (KAERI) started a research project to develop the PHWR (CANDU) nuclear fuel fabrication technology in 1981. Based on the results of the intensive developmental work, several prototype fuel bundles were fabricated and tested in the Hot Test Loop at KAERI continuously in 1983 and 1984. After that, irradiation test and post-irradiation examination were carried out for two KAERI-made fuel bundles at Chalk River Nuclear Laboratories in Canada in 1984. Since the results of in-pile and out-of-pile tests with prototype fuel bundles proved to be satisfactory, 48 additional fuel bundles were loaded in Wolsung reactor (CANDU) in 1984 and 1985, and all of them were discharged without a defect after excellent performance in the power reactor. In 1985, the Korean government decided that KAERI supplies all the fuel necessary for the Wolsung reactor. For the mass production of nuclear fuel bundle, several process ...

1988-01-01

331

Determination of pressure distribution in an aerated bed in a controlled pilot-scale compost reactor  

Energy Technology Data Exchange (ETDEWEB)

This study investigated the effectiveness of dealing with biological waste by composting. In particular, it examined the feasibility of recovering excess thermal energy produced in the process of composting biological waste in terms of mass and energy transport parameters required in the aerated compost bed. An experiment was performed in which a 100 dm{sup 3} adiabatic, leak-tight reactor equipped with a controlled aeration system was constructed to study the temperature and pressure distribution in the bed. Sensors were used to determine the amount and humidity of emitted gases under variable external physical conditions. The perforated bottom of the reactor allowed for bed aeration. As such, the humidity and heat were transported upwards, forced by the air pumped in and by natural convection. In terms of pressure distribution inside the composted and aerated bed, the study results showed that there were considerable differences in pressure ...

2010-07-01

332

Design/build/mockup of the Waste Isolation Pilot Plant gas generation experiment glovebox  

Energy Technology Data Exchange (ETDEWEB)

A glovebox was designed, fabricated, and mocked-up for the WIPP Gas Generation Experiments (GGE) being conducted at ANL-W. GGE will determine the gas generation rates from materials in contact handled transuranic waste at likely long term repository temperature and pressure conditions. Since the customer`s schedule did not permit time for performing R&D of the support systems, designing the glovebox, and fabricating the glovebox in a serial fashion, a parallel approach was undertaken. As R&D of the sampling system and other support systems was initiated, a specification was written concurrently for contracting a manufacturer to design and build the glovebox and support equipment. The contractor understood that the R&D being performed at ANL-W would add additional functional requirements to the glovebox design. Initially, the contractor had sufficient information to design the glovebox shell. Once the shell design was approved, ANL-W built a full scale ...

1996-10-01

333

Corrosion of container materials for disposal of high-level radioactive wastes  

Energy Technology Data Exchange (ETDEWEB)

In the corrosion aspect of container for the deep geological disposal of high-level radioactive waste, disposal concepts and the related container materials, which have been developed by advanced countries, have been reviewed. The disposal circumstances could be divided into the saturated and the unsaturated zones. The candidate materials in the countries, which consider the disposal in the unsaturated zone, are the corrosion resistant materials such as supper alloys and stainless steels, but those in the saturated zone is cupper, one of the corrosion allowable materials. By the results of the pitting corrosion test of sensitized stainless steels (such as 304, 304L, 316 and 316L), pitting potential is decreased with the degree of sensitization and the pitting corrosion resistance of 316L is higher than others. And so, the long-term corrosion experiment with 316L stainless steel specimens, sebsitized and non-sensitized, under the compacted ...

1999-01-01

334

Change in pore structure of coals by activation with KOH; KOH fukatsushita sekitan no saiko kozo  

Energy Technology Data Exchange (ETDEWEB)

Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was studied. The results are summarized as follows: (1) The yield and absorption ability of ...

1996-10-28

335

Binding of vapour-phase mercury (Hg{sup 0}) on chemically treated bauxite residues (red mud)  

Energy Technology Data Exchange (ETDEWEB)

The development and testing of novel control technologies and advanced adsorbent materials continue to be active areas of research. In the present study, Hg capture using adsorbent material derived from the bauxite residue (red mud) from two North American refineries was studied. The red mud, seawater-neutralised red mud, and acid-treated red mud were evaluated for their mercury adsorption capacity and compared with other, more conventional sorbent materials. Two different seawater-neutralised red mud (Bauxsol) samples were treated with HCl and HBr in an effort to increase the mercury sorption capacity. In all cases, the acid treatment resulted in a significant increase in the total surface area and an increase in the total pore volume. The fixed-bed mercury capture experimental results showed that the HBr activation treatment was very effective at increasing the mercury capture performance of both Bauxsol samples whereas the HCl treatment had ...

2008-04-15

336

An experimental study on local scour around group pile foundation  

Energy Technology Data Exchange (ETDEWEB)

This study analyzed the general scour characteristics around group pile foundations through laboratory experiments. The experiments were performed for the pile groups consisting of 4, 9, 15 and 35 piles to investigate the effects of pile number, mean velocity and the angle of attack on the scour hole shape, and the magnitude and the position of maximum scour depth. Results reveal that the maximum scour depth for 4 an d 9 piles have almost same values with single pier case regardless of approach velocity. The scour depth for 15 and 35 piles, however, increases as the mean velocity increases and reaches up to 2.2 times of maximum scour depth for single pier case. As the number of piles increase, the single scour holes are superposed and the overall scour hole turned out to be rectangular shape. The experimental results for the case of 35 piles indicate that the scour depth has the maximum value at angle ...

2001-12-31

337

"2"1"1At-Rh(16-S4-diol) complex as a precursor for astatine radiopharmaceuticals  

International Nuclear Information System (INIS)

"2"1"1At is one of the most promising radionuclides in #alpha#-radioimmunotherapy (#alpha#-RIT). Unfortunately, biomolecules labeled by direct electrophilic astatination are unstable due to the rapid loss of "2"1"1At under both in vitro and in vivo conditions. The present paper describes the results of our studies on attaching At"- to the rhodium(III) complex with thioether ligand: 1,5,9,13-etrathiacyclohexadecane-3,11-diol (16-S4-diol). Rh"3"+ was chosen as a moderately soft metal cation which should form very strong bonds with soft At"- anions, but first of all because of the kinetic inertness of low spin rhodium(III) d"6 complexes. The 16-S4-diol ligand was selected due to formation of stable complexes with Rh"3"+. The experiments related to optimization of the reaction conditions were performed with the "1"3"1I, basing on a chemical similarity of I"- to At"-. The experiments with "2"1"1At were then carried out under the ...

338

Studies of relativistic heavy ion collisions at the AGS (Experiment 814)  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the experimental setup of experiment 814 at Brookhaven AGS. This experiment involves the collision of silicon ions with target nuclei. The detector systems are discussed primarily. (LSP)

1990-01-01

339

[Fundamental biological model for trials of wound ballistics].  

Science.gov (United States)

The aim of our experiment was the testing of effects of common ammunition on usable and slightly accessible biological tissue thereby to create fundamental simple biological model for trials of wounded ballistic. Like objective tissue was elected biological material - pork and beef hind-limbs, pork head, pork bodily cavity. It was discovered that objective tissue is able to react to singles types of shots in all spectrum results namely simple smooth penetration wound as well as splintery fracture in dependence on kind of using ammunition. Pork hind-limb was evaluated like the most suitable biological material for given object. PMID:17172163

2006-10-01

340

Upgraded coal interest group. Quarterly report, July 1, 1995--September 30, 1995  

Energy Technology Data Exchange (ETDEWEB)

The objectives of the Upgraded Coal Interest Group (UCIG) are as follows: Review and update the status of various coal upgrading technologies and developments and critically assess the results. Perform engineering screening analyses on various coal upgrading approaches. Perform commercialization analyses that will promote the availability and use of upgraded coal products by quantifying the benefits of using them. Identify market opportunities for introduction of upgraded coals. Perform critical analyses on a variety of coals and technologies in areas important to users but not readily available. Perform critical experiments which will show the differences between technologies.

1995-12-31

341

Tunable VUV generation by anti-Stokes stimulated Raman conversion of XeCl laser radiation  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on the results of experiments into efficient higher-order anti-Stokes Raman conversion of tunable short-pulse XeCl laser radiation. The maximum output energy of the pumping laser, in which the radiation of a frequency-doubled dye laser is amplified by two XeCl laser amplifiers, is 55 mJ with a pulse duration of 1 ns FWHM. Using hydrogen gas as a Raman medium, a series of anti-Stokes lines up to the 12th order (121.5 nm) is generated in the vacuum ultraviolet (VUV) region. 16 references.

1987-06-01

342

Toward a predictive atomistic model of ion implantation and dopant diffusion in silicon  

Energy Technology Data Exchange (ETDEWEB)

We review the development and application of kinetic Monte Carlo simulations to investigate defect and dopant diffusion in ion implanted silicon. In these type of Monte Carlo models, defects and dopants are treated at the atomic scale, and move according to reaction rates given as input principles. These input parameters can be obtained from first principles calculations and/or empirical molecular dynamics simulations, or can be extracted from fits to experimental data. Time and length scales differing several orders of magnitude can be followed with this method, allowing for direct comparison with experiments. The different approaches are explained and some results presented.

1998-09-18

343

Top Quark Physics with CMS  

CERN Document Server

Several signatures of new physics accessible at the LHC either suffer from top-quark production as a significant background or contain top quarks themselves. In this talk, we present results on top quark physics obtained from the first LHC data collected by the CMS experiment.They include measurements of the top pair production cross section in various channels and their combination, measurements of the top quark mass, the single top cross section, a search for new particles decaying into top pairs, and a first look at the charge asymmetry.

2011-01-01

344

Tidd experience prepares hot gas cleaning technology for commercialization  

Energy Technology Data Exchange (ETDEWEB)

Pressurized fluidized bed combustion (PFBC) is an emerging coal-fired, combined-cycle power generation technology nearing commercial status through several operating and planned demonstration plants throughout the world. Current-generation PFBC plants use ``ruggedized`` gas turbines that can tolerate dust loading common with conventional cyclone gas cleaning. The next generation of PFBC will apply advanced hot gas cleaning systems that will reuse the dust loading to low levels acceptable to high performance, industrial gas turbines. These advances should result in performance and cost advantages. This article examines the demonstration of PFBC technology at Tidd power station.

1995-09-01

345

Theoretical magnon dispersion curves for Gd  

International Nuclear Information System (INIS)

The magnon dispersion curve of Gd metal has been determined from first principles by use of augmented-plane-wave energy bands and wave functions. The exchange matrix elements I (k,k') between the 4f electrons and the conduction electrons from the first six energy bands were calculated under the assumption of an unscreened Coulomb interaction. The results are in good overall agreement with experiment provided the I (k,k') are diminished by a constant scale factor of about 2 which may be caused by screening.

346

The influence of plastic materials on the formation of tars in the gasification of urban waste wood  

Energy Technology Data Exchange (ETDEWEB)

Gasification experiments were performed using urban waste wood (Altholz) with additions of polymers typical for separately collected waste plastics. The resulting tar product distributions are discussed in this paper. The amount of tars is shown to be a function of operation parameters of the gasifier as well as the fuel. Plastics admixture yields higher concentrations of aromatic tar compounds in the gases, even if the plastic used is not aromatic in its structure. Such mixtures can be gasified for the production of synthesis gas, but clearly a larger effort will be required in cleaning the gases. (author)

2001-03-01

347

The ANL X6B beamline at NSLS: A versatile facility  

Energy Technology Data Exchange (ETDEWEB)

We have described the x-ray optics and beamline performance of the ANL X6B beam line at the NSLS. Considerable flexibility has been built into the beam line to accommodate a wide range of x-ray diffraction, scattering, and spectroscopy experiments with various requirements. We presented selected examples of experimental results and showed that with the high intensity, high energy resolution, high-q resolution, and energy tunability, the X6B beam line has become a versatile facility.

1994-07-01

348

The "9"9Tc"m-labelling of diamino-dithiol complexes as brain imaging agents and preliminary biodistribution  

International Nuclear Information System (INIS)

Six kinds of diamino-dithiol compounds are labelled with "9"9Tc"m by ligands exchange reaction. Their ligands exchange percentage is over 95%. The biodistribution of one of these compounds in mice shows 0.88% brain uptake after two minutes and 0.28% after 15 minutes respectively. Although the brain uptake is lower for this compound, it has longer retention in brain. So, the experiment results are valuable to the design of new brain imaging agent in the future.

349

Surface modification of 17-4PH stainless steel by DC plasma nitriding and titanium nitride film duplex treatment  

Energy Technology Data Exchange (ETDEWEB)

17-4PH stainless steel was modified by direct current (DC) plasma nitriding and titanium nitride film duplex treatment in this study. The microstructure, wear resistance and corrosion resistance were characterized by X-ray diffraction (XRD), pin-on-disk tribological test and polarization experiment. The results revealed that the DC plasma nitriding pretreatment was in favor of improving properties of titanium nitride film. The corrosion resistance and wear resistance of duplex treatment specimen was more superior to that of only coated titanium nitride film.

2007-04-15

350

Surface modification of 17-4PH stainless steel by DC plasma nitriding and titanium nitride film duplex treatment  

International Nuclear Information System (INIS)

17-4PH stainless steel was modified by direct current (DC) plasma nitriding and titanium nitride film duplex treatment in this study. The microstructure, wear resistance and corrosion resistance were characterized by X-ray diffraction (XRD), pin-on-disk tribological test and polarization experiment. The results revealed that the DC plasma nitriding pretreatment was in favor of improving properties of titanium nitride film. The corrosion resistance and wear resistance of duplex treatment specimen was more superior to that of only coated titanium nitride film.

2007-04-01

351

Study on the use of zirconium phosphate for radioactive waste treatment  

International Nuclear Information System (INIS)

Zirconium phosphate was one of the earliest inorganic ion-exchange suggested for removing strontium and cesium from aqueous nuclear waste. This paper studied ionic exchange to remove Cs-137 and Sr-90 by using different cationic of zirconium phosphate. In this case the parameters studied were the effect of temperature and ion concentration to percent up take and distribution coefficients. It is also conducted the study on column experiments to determine the breakthrough curves for Cs-137 and Sr-90. The result showed the potential of use of zirconium phosphate in radioactive waste treatment. (author)

1998-12-01

352

Studies of Plasma Confinement in GOL-3 Multi-mirror Trap  

International Nuclear Information System (INIS)

Recent results of the experiments at GOL-3 facility are presented. Plasma with a density of 1014...1016 cm-3 is confined in a 12-meter-long solenoid, which comprises 55 corrugation cells with mirror ratio Bmax/B min=4.8/3.2 T. The plasma is heated up to 2...4 keV temperature by a high power relativistic electron beam (?1 MeV, ? 330 kA, ?8?s, ?120 kJ) injected through one of the ends. Mechanism of experimentally observed fast ion heating, issued of plasma stability and confinement are discussed.

2006-01-01

353

Solid particle receiver experiments: velocity measurements  

Energy Technology Data Exchange (ETDEWEB)

Laser Doppler velocimetry and other photometric techniques are evaluated for measuring the average particle velocity in an ensemble of free-falling particles. The ability to obtain measurements in the presence of a radiant flux as high as 0.6 MW/m/sup 2/ was part of the evaluation. Optically dissimilar particles with diameters ranging from 0.1 mm to 1 mm were used in the study. Experimental results indicate that ensembles of particles do not behave as single isolated particles. The particle motion is dependent on particle volume fraction, and is quite unstable for falls greater than one meter.

1984-10-01

354

Solid particle receiver experiments: velocity measurements  

Science.gov (United States)

Laser Doppler velocimetry and other photometric techniques are evaluated for measuring the average particle velocity in an ensemble of free-falling particles. The ability to obtain measurements in the presence of a radiant flux as high as 0.6 MW/m/sup 2/ was part of the evaluation. Optically dissimilar particles with diameters ranging from 0.1 mm to 1 mm were used in the study. Experimental results indicate that ensembles of particles do not behave as single isolated particles. The particle motion is dependent on particle volume fraction, and is quite unstable for falls greater than one meter.

1984-10-01

355

Simulation of flame-vortex interaction using detailed and reduced  

Energy Technology Data Exchange (ETDEWEB)

The interaction between a pair of counter-rotating vortices and a lean premixed CH{sub 4}/O{sub 2}/N{sub 2} flame ({Phi} = + 0.55) has been studied by direct numerical simulations using detailed and reduced chemical reaction schemes. Results from the complex chemistry simulation are discussed with respect to earlier experiments and differences in the simulations using detailed and reduces chemistry are investigated. Transient evolutions of the flame surface and the total heat release rate are compared and modifications in the evolution of the local flame structure are displayed. (authors) 22 refs.

1996-12-31

356

Simulation of concrete perforation based on a continuum damage model  

Energy Technology Data Exchange (ETDEWEB)

Numerical simulation of dynamic fracture of concrete slabs, impacted by steel projectiles, was carried out in this study. The concrete response was described by a continuum damage model. This continuum damage model was originally developed to study rock fragmentation and was modified in the present study with an emphasis on the post-limit structural response. The model was implemented into a transient dynamic explicit finite element code LS-DYNA2D and the code was then used for the numerical simulations. The specific impact configuration of this study follows the experiment series conducted by Hanchak et al. Comparisons between calculated results and measured data were made. Good agreements were found.

1994-10-01

357

Silicon Detector Letter of Intent  

Energy Technology Data Exchange (ETDEWEB)

This document presents the current status of SiD's effort to develop an optimized design for an experiment at the International Linear Collider. It presents detailed discussions of each of SiD's various subsystems, an overview of the full GEANT4 description of SiD, the status of newly developed tracking and calorimeter reconstruction algorithms, studies of subsystem performance based on these tools, results of physics benchmarking analyses, an estimate of the cost of the detector, and an assessment of the detector R&D needed to provide the technical basis for an optimised SiD.

2010-05-26

358

Shoreline environment atmospheric dispersion experiment (SEADEX)  

Energy Technology Data Exchange (ETDEWEB)

The purpose of SEADEX was to acquire a comprehensive, high-quality data base for evaluating models of dispersion within coastal zones, it secondary objective was to provide data to help determine which meteorological measurements are most appropriate for emergency preparedness at nuclear power plant sites. The study was conducted in the vicinity of Kewannee, Wisconsin, on the western shore of Lake Michigan. This report describes the design of the study and the data base resulting from it. Both a gas tracer (SF/sub 6/) and a particulate tracer (oil fog) were used. (ACR)

1983-09-01

359

Sheath characteristic in ECR plasma nitriding  

International Nuclear Information System (INIS)

The sheath plasma characteristics changing with the negative bias applied to the substrate during electron cyclotron resonance plasma nitriding are studied. The sheath characteristics obtained by a Langmuir single probe and an ion energy analyzer show that when the negative bias applied to the substrate is increasing, the most probable energy of ions in the sheath and the full width of half maximum of ions energy distribution increase, the thickness of the sheath also increases, whereas the saturation current of ion decreases. It has been found from the optical emission spectrum that there are strong lines of N_2 and N_2"+. Based on the experiment results the mechanism of plasma nitriding is discussed

2001-04-01

360

Selection of transverse modes in laser cavities containing waveguides and open parts  

International Nuclear Information System (INIS)

The transverse modes of a submillimetre laser cavity that contains waveguides and open parts were studied theoretically and experimentally with the purpose of finding methods for mode selection. Two methods based on the filtering of the Fourier spectra of the waveguide modes and the use of their interference were substantiated numerically and realised in experiment. Special attention was paid to the mode selection in tunable lasers. Scaling laws allowing one to use the obtained results in a wide range of the cavity parameters and wavelengths are presented. (laser applications and other topics in quantum electronics)

2001-04-30

361

Remark on the effect of varying density of states in superconducting A-15 compounds  

Energy Technology Data Exchange (ETDEWEB)

It is pointed out that a recently claimed result regarding the removal of sharp structure in the electronic density of states N(E) of A-15 superconducting compounds at T approximately equal to Tsub(c) was in fact, shown earlier by one of the present authors (M.N.M.). Merely the variation of N(E) with energy in the vicinity of the Fermi level in these materials cannot explain their anomalous normal state properties and high values of lambda and Tsub(c). Rather a non-varying N(E) accompanied by phonon softening is in better agreement with experiment.

1982-03-01

362

Remark on the effect of varying density of states in superconducting A-15 compounds  

International Nuclear Information System (INIS)

It is pointed out that a recently claimed result regarding the removal of sharp structure in the electronic density of states N(E) of A-15 superconducting compounds at T approximately equal to Tsub(c) was in fact, shown earlier by one of the present authors (M.N.M.). Merely the variation of N(E) with energy in the vicinity of the Fermi level in these materials cannot explain their anomalous normal state properties and high values of lambda and Tsub(c). Rather a non-varying N(E) accompanied by phonon softening is in better agreement with experiment. (author).

363

Reaction pathways of the dissociation of methylal: A DFT study  

Energy Technology Data Exchange (ETDEWEB)

Schemata for modelling combustion processes do not yet include reaction rates for oxygenated fuels like methylal (DMM) which is considered as an additive or replacement for diesel due to its low sooting propensity. Density functional theory (DFT) studies of the possible reaction pathways for different dissociation steps of methylal are presented. Cleavage of a hydrogen bond to the methoxy group or the central carbon atom were simulated at the BLYP/6-311++G{sup **} level of theory. The results are compared to the experiment when dissociating and/or ionising DMM with femtosecond pulses. (author) 1 fig., 1 tab., 1 ref.

1999-08-01

364

Radon concentration measurements in the presence of water and its consequences for Earth sciences studies  

Energy Technology Data Exchange (ETDEWEB)

Radon is often used as a natural tracer for geochemical studies. In many cases radon interacts with water. The aim of this study is to assess the time required for radon to dissolve in water and reciprocally to degas from it, and to estimate the partition ratio between the two phases. A special setup has been devised and built for this purpose. Several experiments carried out with this equipment show that both dissolution and degassing are rapidly achieved phenomena. The qualitative consequence of these results in the field of Earth science are shortly discussed in the paper.

2005-06-01

365

Radiation-induced chemical modification of wood  

International Nuclear Information System (INIS)

The results of theoretical and experimental investigations, describing the effect of ionizing radiation on wood and its main components and methods for production of wood-plastic composites by means of radiation-induced chemical modification are generalized. Domestic and foreign experience in their production is systematized; physico-mechanical characteristics of new material, simulation and calculation of irradiating devices, as well as calculation and experimental study of #gamma#-radiation attenuation both by wood material and by wood of different species are given. Gamma sources ("6"0Co isotope, a hot loop of a nuclear reactor) as well as electron accelerators are considered as ionizing radiation sources.

1985-01-01

366

Proper use of sludge-control additives in residential heating oil systems  

Energy Technology Data Exchange (ETDEWEB)

Discussed are various aspects of heating oil `sludge`: How it forms, typical problems it causes, how sludge-control additives work, what should be expected of them, and what happens in a contaminated system when such additives are used. Test results from laboratory and field experiments demonstrate that performance of commercially available additives varies greatly. The concept of `end-of-the-line` treatment is described and compared with bulk fuel treatment. A procedure is described whereby a retailer can test additives himself, and thus determine just what those additives will or will not do for his business. Finally, the economics of an effective treatment program are outlined.

1995-04-01

367

Primakoff effect in {eta} -photoproduction off protons  

Energy Technology Data Exchange (ETDEWEB)

We analyse data on forward {eta} -meson photoproduction off a proton target and extract the {eta}{yields}{gamma}{gamma} decay width utilizing the Primakoff effect. The hadronic amplitude that enters into our analysis is strongly constrained because it is fixed from a global fit to available {gamma}p{yields}p{eta} data for differential cross-sections and polarizations. We compare our results with present information on the two-photon {eta} -decay from the literature. We provide predictions for future PrimEx experiments at Jefferson Laboratory in order to motivate further studies. (orig.)

2010-05-15

368

Preliminary reactor cavity melt dispersal model for direct containment heating scenarios  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of a series of experiments performed to study the effect of initial pressure vessel conditions on the extent of melt dispersal from scaled reactor cavities and describes progress in development of a mathematical model which is designed to predict the melt mass dispersed from reactor cavities as a function of reactor vessel initial conditions and on the vessel breach area. The model, which is being developed to also characterize the heat transfer and chemical reaction phenomena which would take place within the reactor cavity, is designed to be incorporated into a lumped-parameter containment analysis computer code.

1989-01-01

369

Preliminary Study of Plasma Stream Interaction with Tungsten Target within RPI-IBIS Facility  

International Nuclear Information System (INIS)

The paper presents results of experimental research on the interaction of a pulsed plasma-ion stream with a tungsten (W) target. The pulsed hydrogen plasma was produced within the RPI-IBIS (Multi-Rod Plasma Injector) facility at IPJ in Swierk. Measurements were carried out by means of optical spectroscopy and corpuscular diagnostic techniques. For experiments with the W-target the operational conditions (so-called PID mode) were chosen when a clean hydrogen plasma stream was generated. Attention was paid to the identification of WI and WII spectral lines.

2006-01-01

370

Plasma nitriding of low alloy steels at floating and cathodic potentials  

International Nuclear Information System (INIS)

The low alloy steels were nitrided in the plasma atmosphere generated by using hollow cathode discharge. For comparison, specimens of 40 Cr steel were in two different potential states. One kind is isolated from cathode and anode between them the discharge was created. The other kind is placed on the plate which is connected to the cathode. The nitriding was carried out at different temperatures. The surface morphology, phase of compound layers and microhardness profiles were analyzed. The optical microscopy observation and X-ray diffraction showed that the compound layers were formed in all experiments. The results of the nitriding treatment are weakly dependent on the potentials applied on the specimens.

2008-08-15

371

Phenomenological modeling of two-phase flow for LWRs. I. Experimental study of hydrodynamics of inverted annular flow. II. Simulation study of hot leg U-bend two-phase flow  

International Nuclear Information System (INIS)

In FY 1984 three specific tasks which are all related to not-well-understood two-phase phenomena of importance to LWR accidents have been identified under the program. These three tasks are: (1) inverted annular flow experiments and modeling; (2) hot leg U-bend two-phase flow simulation study; and (3) development and evaluation of two-phase flow scaling criteria. Some of the important results obtained under Tasks (1) and (2) are reported in this paper.

1984-10-23

372

Phase diagram and effective shape of semi-flexible colloidal rods and biopolymers  

CERN Document Server

We study suspensions of semi-flexible colloidal rods and biopolymers using an Onsager-type second-virial functional for a segmented-chain model. For suspensions of thin and thick fd virus particles we calculate phase diagrams in quantitative agreement with experimental observations, and we find their effective state-point dependent shape to be much shorter and thicker than the actual shape. We also calculate the stretching of worm-like micelles in a host fd virus solution, again finding agreement with experiments. For both systems, our results show that the fd virus stiffness can play a key role in system behavior.

2011-01-01

373

Operational Experience with LHC Collimation  

CERN Document Server

A first sub-set of the collimation system has been installed for the 2008 first beam commissioning of the LHC. It included 88 collimators around the ring and the two injection lines. Each collimator has two jaws for which must be controlled and monitored with high precision. The LHC collimation system was put into operation from July to October 2008. The installed system is described and first results from system operation without and with beam are presented. It is shown that the LHC collimation system achieved the specified accuracy and reproducibility of jaw positioning. Next steps in collimation commissioning are described and planned system upgrades for high beam intensities are outlined.

2009-01-01

374

On the self-similarity of fractal colloidal aggregates in two dimensions  

Energy Technology Data Exchange (ETDEWEB)

It is argued that colloidal fractals are self-similar because all computed fractal dimensions of a given fractal have the same value. However, in a mathematical sense the self-similar character of a set implies not only that all fractal dimensions agree in value but also the existence of a set of similarities that generates the fractal. In this paper we report some results from two-dimensional aggregation experiments at the air-liquid interface and show that, with the appropriate selection for the similarities, the colloidal fractal aggregates can be considered as self-similar in a more mathematically rigorous form. (author)

2001-09-14

375

On some mechanisms of 27.2 MeV #alpha#-particle interaction with carbon nuclei  

International Nuclear Information System (INIS)

Using U-120 cyclotron in the course of correlation experiment one studied mechanisms of excitation and decay of "1"2C nucleus states resulting from irradiation of deuterium-polyethylene target by 27.2 MeV energy #alpha#-particle beam via recording of #alpha#-#alpha#-coincidence simultaneously with investigations of #alpha# + d-interactions. Production of "1"2C excited states decaying with the escape of #alpha#-particle and "8Be nucleus in the ground and the excited states is the basic mechanism of the studied #alpha# + "1"2C interaction

2001-05-01

376

On problems in trustworthy predictions of etched track parameters  

Energy Technology Data Exchange (ETDEWEB)

It is discussed here how trustworthy predictions of etched track parameters in nuclear track detection technique can be made? Problems involved in doing so are described along with discussion about their possible solutions. Arguments are presented using 5.2 MeV alpha particle track etching experiments with CR-39 detector and corresponding calculations using computer programs TRACK{sub V}ISION and TRACK{sub T}EST. Experimental and computational results in the present paper are useful for further basic research and technology applications of solid state nuclear track detection technique.

2008-10-15

377

Numerical simulation and experiment research of radiation performance in a dish solar collector system  

British Library Electronic Table of Contents (United Kingdom)

The Monte Carlo ray-tracing method is applied and coupled with optical properties to predict the radiation performance of solar concentrator/cavity receiver systems. Several different cavity geometries are compared on the radiation performance. A flux density distribution measurement system for dish parabolic concentrators is developed. The contours of the flux distribution for target placements at different distances from the dish vertex of a solar concentrator are taken by using an indirect method with a Lambert and a charge coupled device (CCD) camera. Further, the measured flux distributions are compared with a Monte Carlo-predicted distribution. The results can be a valuable reference for the design and assemblage of the solar collector system.

2010-01-01

378

NMR at earth's magnetic field using para-hydrogen induced polarization  

British Library Electronic Table of Contents (United Kingdom)

A method to achieve NMR of dilute samples in the earth's magnetic field by applying para-hydrogen induced polarization is presented. Maximum achievable polarization enhancements were calculated by numerically simulating the experiment and compared to the experimental results and to the thermal equilibrium in the earth's magnetic field. Simultaneous 19F and 1H NMR detection on a sub-milliliter sample of a fluorinated alkyne at millimolar concentration (1018 nuclear spins) was realized with just one single scan. A highly resolved spectrum with a signal/noise ratio higher than 50:1 was obtained without using an auxiliary magnet or any form of radio frequency shielding.

2011-01-01

379

Molecular dynamics study of reaction kinetics in viscous media  

British Library Electronic Table of Contents (United Kingdom)

Predicted by stochastic models and observed experimentally in a number of isomerization reactions, viscosity-induced solvent effects manifest themselves in a significant departure of the reaction rates from the values expected on the basis of transition state theory. These effects are well understood within the framework of stochastic models; however, the predictive power of such models is limited by the fact that their parameters are not readily available. Experiment and molecular dynamics (MD) simulations can provide such information and can serve as the testing grounds for various stochastic models. In real solvents, a change in viscosity is inevitably associated with variation of at least one of the three factors - temperature, pressure, or solvent identity, resulting in different solv...

2011-01-01

380

Molecular dynamics simulations of aqueous ionic clusters using polarizable water  

Energy Technology Data Exchange (ETDEWEB)

The solvation properties of a chlorine ion in small water clusters are investigated using state-of-the-art statistical mechanics. The simulations employ the polarizable water model developed recently by Dang [J. Chem. Phys. [bold 97], 2659 (1992)]. The ion--water interaction potentials are defined such that the successive binding energies for the ionic clusters, and the solvation enthalpy, bulk vertical binding energy, and structural properties of the aqueous solution agree with the best available results obtained from experiments. Simulated vertical electron binding energies of the ionic clusters Cl[sup [minus

1993-11-01

381

Measuring preferences for low-carbon energy technologies in South-East England: the case of electricity generation  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a survey on public preferences in SE England for the use of wind, biomass and nuclear power in electricity generation. Using a labelled CE the perceived importance (value) to the public of distance and the energy options' impacts on biodiversity, emissions, land occupation and household cost was explored. Results suggest that impacts, technology name, demographic characteristics, attitudes towards the environment, knowledge and experience with the technologies were significant choice determinants. Considering the current debate about the development of nuclear power and biomass in UK and worldwide, this survey provides an insight into the factors affecting public acceptability

2008-07-01

382

Magnetization reversal phenomena and domain wall behaviours in nanostructured magnetic systems  

International Nuclear Information System (INIS)

Several recent experiments on micro- (or nano-) structured samples of ferromagnetic materials are introduced. Magnetization reversal phenomena are investigated on submicron wire samples of trilayer structure using the giant magnetoresistance effect. Domain wall movements are sensitively monitored by resistivity measurements and the velocity of propagation is determined. The contribution of domain wall to the resistivity is argued from the results on artificially designed samples of a spring-magnet system. In circular dots of permalloy, the existence of vortex magnetization is confirmed and the reversal of the vortex core magnetization is studied from magnetic force microscopy measurements. (author)

2001-09-23

383

Laser ray-tracing method for optical testing.  

Science.gov (United States)

We have developed a novel laser ray-tracing method to measure aberrations in optical systems. It consists of delivering narrow laser pencils (by a laser scanner), recording the spots that are formed on the image plane (with a CCD camera), and computing the position of each centroid. This approach could be considered an experimental (approximate) implementation of standard numerical ray tracing. Several tests and experiments, including a direct comparison with a Hartmann-Shack wave-front sensor, provided highly satisfactory results that confirmed the validity of the method and revealed potential advantages. PMID:18073906

1999-07-15

384

Ion Transport Measurements in a Multi-Dipole Argon Plasma by Broadband Laser Induced Fluorescence  

International Nuclear Information System (INIS)

Argon ion laser induced fluorescence measurements were carried out in a multipolar filament discharge with a broadband diode laser centered on 668 nm, which stimulated a transition from the metastable state in Ar(II) 3d4F7/2 to 4p4D05/2. The intensity of the induced fluorescence at 442 nm was maximized by the optimization of the discharge parameters and the laser power. From the recovery of the background fluorescence after the laser was turned off, the ion diffusion coefficient was deduced and compared with the result inferred from the experiments of ion acoustic wave (IAW) damping.

2009-06-01

385

Interpretation of EXAFS data from laser shock compressed plasmas  

Energy Technology Data Exchange (ETDEWEB)

Measurements on laser shock compressed aluminium using the EXAFS (Extended X-ray Absorption Fine Structure) technique on the Al K-edge are described. Two methods of analysis of this data were used for the determination of density: the standard EXAFS technique using Fourier transforms and curve fitting, and a method based on a bandstructure calculation of the absorption spectra as a function of compression. These two techniques give results which are in fairly good agreement with each other and also with a hydrodynamic simulation of the experiment. The ion correlation parameter is estimated and shows that two-sided laser irradiation of aluminium foils produces a dense plasma which is strongly coupled. (author).

1989-01-01

386

Inelastic scattering of electrons by close-lying levels of isomeric nuclei  

Energy Technology Data Exchange (ETDEWEB)

The process of inelastic scattering of hot plasma electrons with energies upto 3 keV by a pair of close-lying nuclear levels (..delta../ital E/less than or equal to2keV), one of whichis isomeric, is discussed. The transition cross sections in the nuclei/sup 242/Am, /sup 171/Lu, and /sup 73/Se are calculated. Estimates of the numberof isomeric nuclei de-excited as a result of electron-stimulated processes in aplasma with parameters characteristic of present-day experiments in controlledthermonuclear fusion are given.

1988-11-01

387

Industrial hazardous waste in the framework of EU and international legislation  

British Library Electronic Table of Contents (United Kingdom)

Purpose - The aim of the present study is to present in a systematic way the subject of industrial hazardous waste from the point-of-view of definitions in engineering, science and legislation. This analysis is necessary, as many different approaches and overlapping definitions are used for the classification of waste, leading to different results, a situation that often complicates the collection and interpretation of data on waste. Design/methodology/approach - The study is conducted by bringing together the extended experience of the authors and other experts in the field of environmental legislation and a wide variety of scientific and legislative sources as well as articles and research reports. The focus is the European Union, while several approaches from the international area are ...

2011-01-01

388

Hydrogen flame acceleration and transition to detonation  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the results obtained from two large experimental facilities built at Sandia National Laboratories in Albuquerque, NM. FLAME (Flame Acceleration Measurements and Experiments) is a large horizontal rectangular channel designed to study flame acceleration, transition to detonation, simulation of combustion in containment geometries, component heating, and other problems in hydrogen combustion relevant to reactor safety. The Heated Detonation Tube has been designed to study detonations in hydrogen-air-steam mixtures. Both facilities have been in operation for just over a year. 12 figures.

1984-01-01

389

Hydrogen flame acceleration and transition to detonation  

International Nuclear Information System (INIS)

This paper describes the results obtained from two large experimental facilities built at Sandia National Laboratories in Albuquerque, NM. FLAME (Flame Acceleration Measurements and Experiments) is a large horizontal rectangular channel designed to study flame acceleration, transition to detonation, simulation of combustion in containment geometries, component heating, and other problems in hydrogen combustion relevant to reactor safety. The Heated Detonation Tube has been designed to study detonations in hydrogen-air-steam mixtures. Both facilities have been in operation for just over a year. 12 figures.

1984-10-23

390

Heat exchanger tube vibration: comparison between operating experiences and vibration analyses  

International Nuclear Information System (INIS)

Tube failures due to excessive flow-induced vibration must be avoided to assure the reliable performance of heat exchangers. Such components must be thoroughly analysed for vibration at the design stage. Several flow-induced vibration mechanisms are possible. In this paper, particular attention is given to fluidelastic instability of tube bundles subjected to liquid and two-phase cross-flow. The performance of ten operating heat exchanger components is reviewed to validate our recommended vibration analysis guidelines. Both tube failure histories and satisfactory performances are considered. The results show that a fluidelastic instability constant K=3.3 is a reasonable design criterion. (auth).

1992-12-01

391

Getter pumping  

CERN Document Server

A surface may provide a useful pumping action when able to retain adsorbed gas molecules for the duration of a given experiment. To fulfil this condition at room temperature, strong binding forces, as those resulting from chemical reactions, are required. Materials able to react with gases to form stable chemical compounds are called getters. The two main families of getters (evaporable and non-evaporable, or NEG) are presented and discussed. Special emphasis is placed on the NEG strips currently used for the vacuum systems of particle accelerators, and on the newly developed NEG thin-film coatings, in view of their possible future applications.

2007-01-01

392

Gasoline from coal: the pioneering South African experience  

Energy Technology Data Exchange (ETDEWEB)

The fact that South Africa had no commercially significant deposits of crude oil necessitated the early development of production of gasoline from coal which was present in abundance in low to medium grade in thick seams, the development of the process since the early 1950s is discussed. Both the Fischer Tropsch and Lurgi processes are used, and three large plants named Sasol One, Two, and Three have been completed. A flow diagram for the Lurgi process as used in these plants is included. Typical products and their properties resulting from the Sasol-type Synthol operation are presented in tabular form. Marketing considerations and economics of production of the Sasol products are discussed briefly. (BLM)

1982-03-01

393

Gasoline from coal: the pioneering South African experience  

Science.gov (United States)

The fact that South Africa had no commercially significant deposits of crude oil necessitated the early development of production of gasoline from coal which was present in abundance in low to medium grade in thick seams, the development of the process since the early 1950s is discussed. Both the Fischer Tropsch and Lurgi processes are used, and three large plants named Sasol One, Two, and Three have been completed. A flow diagram for the Lurgi process as used in these plants is included. Typical products and their properties resulting from the Sasol-type Synthol operation are presented in tabular form. Marketing considerations and economics of production of the Sasol products are discussed briefly. (BLM)

1982-03-01

394

Fusion of the "8 Li + "2"0"8 Pb system at near-barrier energies studied via x n evaporation  

International Nuclear Information System (INIS)

The fusion excitation function for the radioactive projectile "8 Li on a "2"0"8 Pb target has been measured at energies near the Coulomb barrier. The results show that in the considered energy interval, the evaporation of four neutrons is the most relevant mechanism. However, at the highest energies used in the experiment, the Sn channel begins to appear. The preliminary experimental cross sections show a good agreement with the predictions of a simple evaporation calculation using the code PACE. (Author) 16 refs., 1 tab., 4 figs.

2004-12-01

395

Focusing atomic beams by the dissipative radiation-pressure force of laser light  

Science.gov (United States)

An experimental realization of the focusing of an atomic beam by a spontaneous radiation pressure force is reported. A simple light field configuration for focusing an atomic beam is described which is formed by four divergent Gaussian laser beams propagating along the + or - x and + or - y directions of a Cartesian coordinate system. An experimental arrangement for the laser focusing is shown, and the experimental procedure is described. The resulting atomic beam profiles are shown and discussed. It is concluded that the experiments open up the possibility of gaining control over such parameters of atomic beams as their density and divergence. 7 references.

1986-02-01

396

Finite element prediction of differential eddy current probe signals from Fe _30_4 deposits in PWR steam generators  

International Nuclear Information System (INIS)

The paper is concerned with the simulation of practical testing situations which are too difficult and/or expensive to replicate in a laboratory environment. Numerical experiments are described which simulate the differential eddy current probe response to the build-up and chemical flushing of magnetite in the crevice gap of a PWR steam generator unit. The simulation results agree well with the only experimental data available to the authors and lead to the conclusion that conventional differential eddy current probes should be capable of characterizing crevice gap conditions with respect to the presence of magnetite. (author).

1985-01-01

397

Ferrofluid flow for TOUGH2  

Energy Technology Data Exchange (ETDEWEB)

We have developed EOS7M, a ferrofluid flow and transport module for TOUGH2. EOS7M calculates the magnetic forces on ferrofluid caused by an external magnetic field and allows simulation of flow and advective transport of ferrofluid-water mixtures through porous media. Such flow problems are strongly coupled and well suited to the TOUGH2 framework. Preliminary applications of EOS7M to some simple pressure and flow problems for which experiments were carried out in the lab show good qualitative agreement with the laboratory results.

1998-03-24

398

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

399

FFTF operating experience 1982-1984  

International Nuclear Information System (INIS)

The Fast Flux Test Facility (FFTF) is a 400 MWt sodium-cooled fast reactor operated by Westinghouse Hanford Company for the US Department of Energy to conduct fuels and materials testing in support of the US Liquid Metal Fast Breeder Reactor programme. Early in 1982, the FFTF began its first 100 day irradiation cycle. Since that time the plant has operated very well, achieving a cycle capacity factor of 94 per cent in the most recent irradiation cycle. The authors describe the results achieved in the first three cycles of operation and carrying through to the fourth reactor cycle which began in January 1984. (author).

400

FFTF (Fast Flux Test Facility) Reactor Characterization Program: Absolute Fission-rate Measurements  

Energy Technology Data Exchange (ETDEWEB)

Absolute fission rate measurements using modified National Bureau of Standards fission chambers were performed in the Fast Flux Test Facility at two core locations for isotopic deposits of {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu. Monitor chamber results at a third location were analyzed to support other experiments involving passive dosimeter fission rate determinations.

1981-05-01

401

FFTF (FAST FLUX TEST FACILITY) REACTOR CHARACTERIZATION PROGRAM ABSOLUTE FISSION RATE MEASUREMENTS  

Energy Technology Data Exchange (ETDEWEB)

Absolute fission rate measurements using modified National Bureau of Standards fission chambers were performed in the Fast Flux Test Facility at two core locations for isotopic deposits of {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu. Monitor chamber results at a third location were analyzed to support other experiments involving passive dosimeter fission rate determinations.

1981-05-01

402

Experimental technique to observe weak localization in thin silver films  

CERN Document Server

A simple experiment to observe weak localization in thin Ag films is presented. A clear theoretical signature of weak localization is predicted in mangetoresistive measurements of thin films samples. We present a simple method for making thin Ag film samples, using evaporative deposition, and observing the small magnetoresistive signal, using a resistance bridge technique. Typical results from our students show that Ag films show the predicted behavior for weak localization with spin effects. These effects can be easily observed in a liquid helium dewar.

2005-01-01

403

Experimental Study of Plasma-Surface Interaction and Material Damage Relevant to ITER Type I Elms  

International Nuclear Information System (INIS)

The paper presents experimental investigations of main features of plasma surface interaction and energy transfer to the material surface in dependence on plasma heat loads. The experiments were performed with QSPA repetitive plasma pulses of the duration of 0.25 ms and the energy density up to 2.5 MJ/m2. Surface morphology of the targets exposed to QSPA plasma screams is analyzed. Relative contribution of the Lorentz force and plasma pressure gradient to the resulting surface profile is discussed. development of cracking on the tungsten surface and swelling of the surface are found to be in strong dependence on initial temperature of the target.

2006-01-01

404

Evaluation of efficacy of radiation-sterilized females for population suppression of Earias vittella (Fabricius)  

International Nuclear Information System (INIS)

Feasibility of using sterile females for population suppression of Earias vittella (Fabricius) was evaluated by conducting studies on mating competitiveness of radiation sterilized females, both in individual pairs and in simulated large population conditions. Results showed that sterility induced by using a 10:1:1 ratio (sterile female: normal female: normal male) in single pair experiments and also in simulated large population conditions was more than 99.0 per cent. Release of radiation- sterilized females of E. vittella in natural populations has thus an excellent potential for population suppression. (author)

405

Energy-band-structure studies of NbN(100) and VN(100)  

Energy Technology Data Exchange (ETDEWEB)

Band-structure studies of NbN and VN are reported. The results of angle-resolved photoemission experiments performed on NbN/sub 0.93/ and VN/sub 0.89/ are presented. The bulk-band structures calculated for stoichiometric NbN and VN using the linearized augmented-plane-wave method are presented and utilized in the interpretation of the experimental spectra. It is shown that most of the features in the spectra can be accounted for by direct bulk-band transitions. A fairly good agreement between experimental and calculated band locations and dispersions is obtained.

1985-07-15

406

Electronic structure of one-to-one and defect scandium sulfide  

Energy Technology Data Exchange (ETDEWEB)

Self-consistent electronic structure calculations have been performed on two compositions of scandium sulfide ScS and Sc/sub 3/S/sub 4/. The results of the calculation of ScS are similar to those obtained for other transition metal chalcogenides and are in excellent agreement with heat capacity and reflectance measurements as well as UPS experiments. The calculation of the defect structure indicates the creation of sulfur p nonbonding states in metal-deficient ScS. The valency of the metal ions remains unchanged upon the creation of vacancies.

1984-03-01

407

Electron beam therapy in carcinoma of the buccal mucosa  

Energy Technology Data Exchange (ETDEWEB)

Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).

1990-10-01

408

Electron beam therapy in carcinoma of the buccal mucosa  

International Nuclear Information System (INIS)

Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).

409

Effect of chloride concentration and pH on pitting corrosion of waste package container materials  

Energy Technology Data Exchange (ETDEWEB)

Electrochemical cyclic potentiodynamic polarization experiments were performed on several candidate waste package container materials to evaluate their susceptibility to pitting corrosion at 90 degrees C in aqueous environments relevant to the potential underground high-level nuclear waste repository. Results indicate that of all the materials tested, Alloy C-22 and Ti Grade-12 exhibited the maximum corrosion resistance, showing no pitting or observable corrosion in any environment tested. Efforts were also made to study the effect of chloride ion concentration and pH on the measured corrosion potential (Ecorr), critical pitting and protection potential values.

1996-12-01

410

Direct dark matter identification with a hybrid detection technique  

CERN Document Server

In the quest to understand the ultimate nature of WIMPs, we propose the use of a hybrid detection technique: cylinders filled with liquefied noble gasses, acting as targets, are immersed inside a tank of Gd-doped ultra-pure water that provides an active and efficient veto against neutrons. The evaluation of the background rejection capabilities and physics potential of this instrument have been carried out through a full GEANT4 simulation, assuming the detector will be located at the Canfranc underground laboratory (in the Spanish Pyrenees). Our results compare very favourably with existing or planned experiments in the field. This technique is scalable and will allow to reach target masses of few tonnes in the next future.

2008-01-01

411

Dependence of laser assisted cleaning of clad surfaces on the laser fluence  

International Nuclear Information System (INIS)

The decontamination factor is studied as a function of laser fluence for three kinds of clad surfaces viz., plain zircaloy, autoclaved zircaloy and SS with cesium as the test contamination. It has been found that the decontamination factor exhibits a maximal behaviour with the laser fluence and its maximum value occurs at different laser fluences in the three cases. The maximal behaviour is attributed to reduced coupling of energy from the laser beam to the substrate due to the initiation of surface-assisted optical breakdown. The results obtained in the experiment carried out in helium environment qualitatively support this explanation (author)

2005-11-01

412

Decontamination of building surface using clay suspension  

Energy Technology Data Exchange (ETDEWEB)

The decontamination of the urban building surfaces, based on the covering of clay suspensions, has been studied. Contaminated samples for test purpose were prepared by application of radioactive solution which was extracted from the soil of 2 km zone of the Chernobyl Nuclear Power Plant(ChNPP). The cation converting conditions of clay suspensions were determined by the experiments of swelling and stability of the suspensions. According to the experimental results, the most effective clay suspension was the NH{sub 4}-type which had a 7.1 of decontamination factor(DF) on Cs and 4.5 of DF on total nuclides after 3 times covering on slate.

1994-07-01

413

Decontamination factors and release rates of UO/sub 2/ particles from boiling pools of sodium  

Energy Technology Data Exchange (ETDEWEB)

A semi-mechanistic model for calculating solid radionuclide release rates from bubbling pools of sodium was developed. The influence of particle spacial and size distributions on the decontamination of the releases was analysed and found significant. Decontamination factors are shown as a function of pool depth, bubbling characteristics and particle size distribution. The calculation of a decontamination factor for estimating the source term of large scale hypothetical core disruptive accidents is presented. The decontamination factor for a large scale accident was found to be two orders of magnitude greater than results obtained from small scale experiments conducted with uniform particle distributions.

1983-01-01

414

Decontamination factors and release rates of UO"2 particles from boiling pools of sodium  

International Nuclear Information System (INIS)

A semi-mechanistic model for calculating solid radionuclide release rates from bubbling pools of sodium was developed. The influence of particle spacial and size distributions on the decontamination of the releases was analysed and found significant. Decontamination factors are shown as a function of pool depth, bubbling characteristics and particle size distribution. The calculation of a decontamination factor for estimating the source term of large scale hypothetical core disruptive accidents is presented. The decontamination factor for a large scale accident was found to be two orders of magnitude greater than results obtained from small scale experiments conducted with uniform particle distributions. (orig.).

415

Conceptual Assessment Framework for Forested Wetland Restoration: The Pen Branch Experience. Restoration of a Severely Impacted Riparian Wetland System - The Pen Branch Project  

Energy Technology Data Exchange (ETDEWEB)

Development of an assessment framework and indicators can be used to evaluate effectiveness of wetland restoration. Example of these include index of biotic integrity and the hydrogeomorphic method. Both approaches provide qualitative ranks. We propose a new method based on the EPA wetland research program. Similar to other methods, indexes are compared to reference communities; however, the comparisons are quantitative. In this paper we discuss the results of our framework using the Pen Branch riparian wetland system as an example.

2000-10-01

416

Collective ion acceleration by a reflexing electron beam: model and scaling. Memorandum report  

Energy Technology Data Exchange (ETDEWEB)

Analytical and numerical calculations are presented for a reflexing electron beam type of collective ion accelerator. These results are then compared to those obtained through experiment. By constraining one free parameter to experimental conditions, the self-similar solution of the ion energy distribution agrees closely with the experimental distribution. Hence the reflexing beam model appears to be a valid model for explaining the experimental data. Simulation shows in addition to the agreement with the experimental ion distribution that synchronization between accelerated ions and electric field is phase unstable. This instability seems to further restrict the maximum ion energy to several times the electron energy.

1984-05-11

417

Chemical reactions in a solar furnace 2: Direct heating of a vertical reactor in an insulated receiver. Experiments and computer simulations  

Energy Technology Data Exchange (ETDEWEB)

The performance of a solar chemical heat pipe was studied using CO{sub 2}reforming of methane as the endothermic reaction. A directly heated vertical reactor, packed with a rhodium catalyst was used. The solar tests were carried out in the Schaeffer solar furnace of the Weizmann Institute of Science. The power absorbed was up to 6.3 KW, the maximal flow rates of the gases reached 11,000 1/h, and the methane conversions reached 85%. A computer model was developed to simulate the process. Agreement of the calculations with the experimental results was quite satisfactory.

1992-01-01

418

Calibration system for spot welding robots in offline-teaching; Offline teaching ni okeru spot yosetsu robot yo calibration system  

Energy Technology Data Exchange (ETDEWEB)

Calibration system for spot welding robots has been developed. The purpose of this system is to reduce the misalignment of tool center point (TCP) generated when teaching data made by off-line system is input to an actual robot. After the factor of the misalignment was analyzed, the relation between a main factor and the misalignment was modeled. In addition, the model was verified on experiment. The achievement of the accuracy requirement and practical use in the site was confirmed by the result of the verification. (author)

1999-04-01

419

Boiling transition under thermal hydraulic instability in rod bundle  

International Nuclear Information System (INIS)

Experiments have been performed on the electrically heated rod bundles to investigate the characteristics of the boiling transition under flow oscillation (OSBT) during thermal hydraulic instability. After determining the instability threshold power (Q/sub OS/), the electrical power to the test section was increased further up to the threshold power (Q/sub OSBT/) at which it was detected by the thermocouples that the boiling transition (BT) occurred and the heater rod temperature reached 613 K. Experimental results show that Q/sub OSBT/ is larger than Q/sub OS/ by a certain margin, which depends on the test conditions.

420

Autonomic Management of Maintenance Scheduling in Chord  

CERN Document Server

This paper experimentally evaluates the effects of applying autonomic management to the scheduling of maintenance operations in a deployed Chord network, for various membership churn and workload patterns. Two versions of an autonomic management policy were compared with a static configuration. The autonomic policies varied with respect to the aggressiveness with which they responded to peer access error rates and to wasted maintenance operations. In most experiments, significant improvements due to autonomic management were observed in the performance of routing operations and the quantity of data transmitted between network members. Of the autonomic policies, the more aggressive version gave slightly better results.

2010-01-01

421

Application of a 3-beam #gamma# densitometer to two-phase flow regime and density measurements  

International Nuclear Information System (INIS)

A method of using gamma radiation to determine the density and phase distribution in two-phase flows in pipes is described. Three collimated beams of radiation that pass through a pipe cross-section at different radial positions are used. A theory and computer program used to relate the measured attenuation of these beams to a three-parameter model of the phase distribution and to the average density and void fraction are discussed. Data obtained during both static and dynamic verification experiments using Lucite inserts are presented, as well as the results of several tests done in high pressure, steam-water flows.

1976-08-11

422

Antimicrobial potential of Glycyrrhiza glabra roots  

British Library Electronic Table of Contents (United Kingdom)

The present study was aimed to investigate antimicrobial potential of Glycyrrhiza glabra roots. Antimycobacterial activity of Glycyrrhiza glabra was found at 500mg/mL concentration. Bioactivity guided phytochemical analysis identified glabridin as potentially active against both Mycobacterium tuberculosis H37Ra and H37Rv strains at 29.16mg/mL concentration. It exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. Our results indicate potential use of licorice as antitubercular agent through systemic experiments and sophisticated anti-TB assay.

2008-01-01

423

Analytic description of X-ray fluorescence intensity as a function of the particle size in powder samples and pulp upon X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Analytic expression is derived for X-ray fluorescence dependence on the particle size of powder and slurry media. The expression is obtained for a model of powder medium containing particles of different size and random distribution in the bulk of the sample. Limiting cases of homogeneous and slurry-like media are considered and expressions for calculation of the fluorescence intensity are derived. The results reasonably match the experiment for binary powder mixtures and thus provide evaluation of the powder particle size on the fluorescence intensity for multicomponent polydisperse powder medium

2007-11-01

424

Analysis of convective losses from cavity solar central receivers  

Energy Technology Data Exchange (ETDEWEB)

An analytical model is presented which enables the estimation of convective losses from cavity receivers. Evidence from solar experiments is used to test the hypothesized mechanisms. The analytical results and experimental evidence indicate that the convective loss from cavity receivers is appreciable. The model indicates that the influences of the wind on the convective loss at normal operating conditions are minimal. It also shows that the internal thermal resistance, i.e. the ability to heat the air inside the cavity, are of importance. Buoyancy induced flows are, on the other hand, effective in transferring energy across the aperture. 8 refs.

1981-01-01

425

An investigation of the retention of some radioelements on natural fibers  

International Nuclear Information System (INIS)

The retention of radio-Eu, Go, Cs and Sr, at the tracer level, on raw fibers produced from hemp, linen and Jute plants was investigated. The study was conducted from different media including: sea and tap waters, sodium chloride and nitric acid solutions of different Ph. The percentage retention and elution, on prolonged contact, varied from one element to another depending on conditions. Extraction chromatography columns, using these fibers as supporting material were also experimented. Results were discussed together with possible applications. 7 tabs.

426

A high stopping power, large acceptance Bragg curve spectrometer for heavy ion detection  

Energy Technology Data Exchange (ETDEWEB)

A large acceptance, high stopping power Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. Factors affecting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).

1991-05-01

427

A high stopping power, large acceptance Bragg curve spectrometer for heavy ion detection  

International Nuclear Information System (INIS)

A large acceptance, high stopping power Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. Factors affecting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).

428

A Geometrical Model for Non-Zero $\\theta_{13}$  

CERN Document Server

Based on Friedberg and Lee's geometric picture by which the tribimaximal PMNS leptonic mixing matrix is constructed, namely corresponding mixing angles correspond to the geometric angles among the sides of a cube. We suggest that the three realistic mixing angles which slightly deviate from the values determined for the cube, are due to a viable deformation from the perfectly cubic shape. Taking the best fitted results of $\\theta_{12}$ and $\\theta_{23}$ as inputs, we determine the central value of $\\sin^22\\theta_{13}$ should be 0.0238 with a relatively large error tolerance, this value lies in the range of measurement precision of the Daya Bay experiment.

2011-01-01

429

A Framework for Understanding Golfing Visitors to a Destination  

British Library Electronic Table of Contents (United Kingdom)

The purpose of this study is to determine whether there are differences among visitors to a destination based on their golfing frequency in the previous year. By constructing a framework for understanding the golf traveller, golf and tourism industry representatives can better understand the contribution that golfers make to a destination based on factors such as satisfaction, perceived value received from the golfing experience, trip length, expenditures, travel decisions, and motivations. The results indicate that there are significant differences between golfers based on golfing frequency. Dedicated golfers are very different from infrequent and moderate golfers on three of the four variables used to profile these visitors. Findings from this research may provide golf and tourism market...

2008-01-01

430

A study on the treatment of radioactive liquid wastes using synthetic by air intake system  

Energy Technology Data Exchange (ETDEWEB)

In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste ...

2003-07-01

431

Thermal modeling of solar central receiver cavities  

Energy Technology Data Exchange (ETDEWEB)

Results are presented from a numerical model of the steady-state energy transfer in molten-salt-in-tube solar cavity receivers that includes convective energy transfer at a local (spatially resolved) level. Molten salt energy absorption and gray radiative transfer between all cavity surfaces are also included. This model is applied to the Molten Salt Subsystem Component Test Experiment (MSS/CTE) cavity receiver. Results for this receiver indicate the global (entire cavity) receiver thermal efficiency is invariant within a few percent to most parameters investigated, although front surface temperatures of the nonabsorbing walls vary considerably, and are particularly sensitive to the type of convective submodel used. Absorption efficiencies indicate the effects of the cavity enclosure environment. For all conditions investigated, tube inner wall temperatures remain under 855 K, ensuring that the salt remains chemically ...

1989-05-01

432

The preparation and properties of some activated carbons modified by treatment with phosgene or chlorine  

Energy Technology Data Exchange (ETDEWEB)

Treatment of coal or coconut shell activated carbons with either phosgene or chlorine at 180{degree}C followed by washing with methanol or water results in chlorinated carbons with very similar pore structures to their precursors. Water adsorption experiments show that the modified materials are relatively hydrophobic, presumably as a result of replacement of oxygen-containing surface groups by chlorine. Adsorption of the model hydrophobic vapour chloropicrin from humid air is usually better for the modified carbons which, unlike the controls, do not appear to be subject to degradation in performance on ageing in a humid atmosphere. The stability of the modified carbons is probably a consequence of the chlorination of those sites on the control carbons that are prone to ready oxidation or hydroxylation. 1 tab., 2 figs., 17 refs.

1992-01-01

433

SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: First Results Report  

Energy Technology Data Exchange (ETDEWEB)

This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This report provides the early data results and implementation experience of the AT fuel cell bus since it was placed in service.

2011-03-01

434

Primary results of measuring plasma electron temperature with YAG laser thomson scattering system on the HL-2A tokamak  

International Nuclear Information System (INIS)

This article describes the laser Thomson scattering principle and the developed system on HL-2A device. The high power Q-switch Nd:YAG laser, with a wavelength of 1064 nm, can sufficiently satisfy the measurement requirement. The polycromator consisting of avalanche photo-diodes(APD) and narrow band interference filters, can effectively improve the measurement of scattering light. The electron temperature is deduced by error-weighted lookup table method, which improves the data- processing speed or efficiency. Finally, the experiment results of the one-point electron temperature during different discharges of plasma are presented. (authors)

2008-07-01

435

Preliminary assessment of condensation behavior for hydrocarbon-vapor expansions which cross the saturation line near the critical point  

Energy Technology Data Exchange (ETDEWEB)

Previous analyses of binary cycles for conversion of geothermal energy from moderate temperature resources to electrical energy have shown potential gains in net geofluid effectiveness of on the order of 8%, resulting from selection of turbine-expansion processes whose equilibrium states pass through the two-phase region (assuming major condensation does not occur). If condensation occurs, this gain could be reduced or eliminated by the resulting loss in turbine efficiency. Experience with many fluids, however, indicates that vapor supersaturation (or subcooling) permits metastable pure-vapor states to exist at temperatures considerably below the saturation temperature at a given pressure; thus, by better understanding the condensation process, and properly structuring the cycle, substantial performance gains may be achievable. The present study assessed, qualitatively, the probability for attaining this performance gain.

1982-07-01

436

On external network model development  

Energy Technology Data Exchange (ETDEWEB)

Although state estimation is a mature technique which is widely available in the EMS industry, experience with practical implementation and use of state estimation and network security analysis functions at electric power utilities over the last two decades indicates recurring difficulties and problems attributable to inadequate external network modeling detail and data. This paper addresses the development of a set of guidelines for external network modeling and data exchange, based on the results of a recent project sponsored by EPRI. A general methodology is developed based on the results of a survey of a representative set of utilities and EMS suppliers, supplemented by subsequent analysis and simulation studies. Distinction is made between guidelines pertaining to external network topology, analog measurements, data exchange, and implementation procedures. A philosophy and approach for constructing and testing external ...

1996-05-01

437

Numerical and experimental investigation of shellside characteristics for RODbaffle heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

RODbaffle heat exchanger is a kind of shell-and-tube heat exchanger with eminent performance. Because of the characteristics of tube bundle support structure, fluid flow on shellside is longitudinal and periodical, and fluid flow is of symmetry in landscape orientation. According to the fluid flow characteristics on shellside and ignoring the impact of inlet, outlet and shell wall, a periodic flow unit duct was taken as the simplified model of the shellside to perform numerical simulation by using CFD code, FLUENT. It was found that the both errors in magnitude of the main fluid velocities and heat transfer coefficients between results of simulation and that of experiment or correlations are less than 10%, and the errors of pressure drop between simulation and correlation are no more than 20%. The detailed characteristics and relation of fluid flow and heat transfer on shellside of the RODbaffle heat exchanger were analyzed using the simulation ...

2008-05-15

438

New highly active oxygen reduction electrode for PEM fuel cell and Zn/air battery applications (NORA). Final report  

Energy Technology Data Exchange (ETDEWEB)

This illustrated final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project concerning a new, highly active oxygen reduction electrode for PEM fuel cell and zinc/air battery applications. The goal of this project was, according to the authors, to increase the efficiency of the oxygen reduction reaction by lowering the activation polarisation through the right choice of catalyst and by lowering the concentration polarisation. In this work, carbon nanotubes are used as support material. The use of these nanotubes grown on perovskites is discussed. Theoretical considerations regarding activation polarisation are discussed and alternatives to the use of platinum are examined. The results of experiments carried out are presented in graphical and tabular form. The paper is completed with a comprehensive list of references.

2008-04-15

439

Morphology, structure, and conductivity of polypyrrole prepared in the presence of mixed surfactants in aqueous solutions  

British Library Electronic Table of Contents (United Kingdom)

Polypyrrole (PPy) was prepared from different mixed-surfactant solutions with ammonium persulfate as an oxidant. Three types of combinations were selected, including cationic/anionic, cationic/nonionic, and anionic/nonionic mixed-surfactant solutions. The surfactants used in the experiments included cetyltrimethylammonium bromide (cationic surfactant), sodium dodecyl sulfate (anionic surfactant), sodium dodecyl sulfonic acid salt (anionic surfactant), poly(vinyl pyrrolidone) (nonionic surfactant), and poly(ethylene glycol) (nonionic surfactant). The morphology, structure, and conductivity of the resulting PPy were investigated in detail with scanning electron microscopy, Fourier transform infrared spectra, and the typical four-probe method, respectively. The results showed that the interac...

2007-01-01

440

Modeling of Anisotropic Inelastic Behavior  

Energy Technology Data Exchange (ETDEWEB)

An experimental capability, developed at Lawrence Livermore National Laboratory (LLNL), is being used to study the yield behavior of elastic-plastic materials. The objective of our research is to develop better constitutive equations for polycrystalline metals. We are experimentally determining the multidimensional yield surface of the material, both in its initial state and as it evolves during large inelastic deformations. These experiments provide a more complete picture of material behavior than can be obtained from traditional uniaxial tests. Experimental results show that actual material response can differ significantly from that predicted by simple idealized models. These results are being used to develop improved constitutive models of anisotropic plasticity for use in continuum computer codes.

2000-02-25

441

Mass measurement of neutron-rich isotopes from [sup 51]Ca to [sup 72]Ni  

Energy Technology Data Exchange (ETDEWEB)

The ground state masses of thirty-nine neutron-rich nuclei from [sup 51]Ca to [sup 72]Ni have been measured using the Time-of-Flight Isochronous (TOFI) spectrometer. Eight of these masses have been measured for the first time and thirty-one are remeasurements of neutron-rich nuclei previously reported. Good agreement between these results and a previous TOFI experiment was observed except for the most neutron-rich isotopes of vanadium through iron with the present results being more bound and in better agreement with theory. The low binding energy of [sup 68]Ni, as indicated by an unreasonably low two-neutron separation energy, suggests the presence of a high-lying, long-lived isomeric state in this nucleus. (orig.)

1994-07-01

442

Mass measurement of neutron-rich isotopes from "5"1Ca to "7"2Ni  

International Nuclear Information System (INIS)

The ground state masses of thirty-nine neutron-rich nuclei from "5"1Ca to "7"2Ni have been measured using the Time-of-Flight Isochronous (TOFI) spectrometer. Eight of these masses have been measured for the first time and thirty-one are remeasurements of neutron-rich nuclei previously reported. Good agreement between these results and a previous TOFI experiment was observed except for the most neutron-rich isotopes of vanadium through iron with the present results being more bound and in better agreement with theory. The low binding energy of "6"8Ni, as indicated by an unreasonably low two-neutron separation energy, suggests the presence of a high-lying, long-lived isomeric state in this nucleus. (orig.).

443

Magnetic Moments and Electromagnetic Radii of Nucleon and ?(1232) in an Extended Goldstone-Boson-Exchange Model  

International Nuclear Information System (INIS)

We derive the exchange currents of pseudoscalar, vector, and scalar mesons from Feynman diagrams, and use them to calculate the magnetic form factors of nucleon and ?(1232). The magnetic moments and electromagnetic radii are obtained by using those form factors and the parameters determined from the masses of nucleon and ?(1232). We find the magnetic moments and electromagnetic radii of nucleon and ?(1232) can be produced very well in the extended Goldstone-Boson-exchange model in which all of pseudoscalar, vector, and scalar meson nonet are included. The magnetic moments of ?(1232) are closer to experiment values and results from lattice calculation than the results obtained by the model without other mesons except for pion and sigma.

2005-01-15

444

Large-Scale Simulation of Beam Dynamics in High Intensity Ion Linacs Using Parallel Supercomputers  

CERN Document Server

In this paper we present results of using parallel supercomputers to simulate beam dynamics in next-generation high intensity ion linacs. Our approach uses a three-dimensional space charge calculation with six types of boundary conditions. The simulations use a hybrid approach involving transfer maps to treat externally applied fields (including rf cavities) and parallel particle-in-cell techniques to treat the space-charge fields. The large-scale simulation results presented here represent a three order of magnitude improvement in simulation capability, in terms of problem size and speed of execution, compared with typical two-dimensional serial simulations. Specific examples will be presented, including simulation of the spallation neutron source (SNS) linac and the Low Energy Demonstrator Accelerator (LEDA) beam halo experiment.

2000-01-01

445

K S Krishnan and the early experimental evidences for the Jahn-Teller Theorem  

CERN Document Server

Jahn-Teller theorem, proposed in 1937, predicts a distortional instability for a molecule that has symmetry based degenerate electronic states. In 1939 Krishnan emphasized the importance of this theorem for the arrangement of water molecules around the transition metal or rare earth ions in aqueous solutions and hydrated saltes, in a short and interesting paper published in Nature by pointing out atleast four existing experimental results in support of the theorem. This paper of Krishnan has remained essentially unknown to the practitioners of Jahn-Teller effect, eventhough it pointed to the best experimental results that were available, in the 30's and 40's, in support of Jahn-Teller theorem. Some of the modern day experiments are also in conformity with some specific suggestions of Krishnan.

1998-01-01

446

Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress. Untersuchungen zur Beurteilung des Betriebsverhaltens kriechbeanspruchter Bauteile aus Alloy 800 und Alloy 617  

Energy Technology Data Exchange (ETDEWEB)

The program introduced here for determining and describing the multi-axial creep of pipes is based, on the one hand, on the results of the nuclear process heat prototype plant material program and, on the other hand, on the possible load conditions which arise for evaluating accidents or extreme working situations. The basis of a theoretical description of multi-axial creep is the invariant theory in which both the von Mises configuration change hypothesis and the Norton creep law are included. Combined tension and torsion are also considered in detail, the superimposition of cyclic stresses in the tensile threshold area is discussed and cases of partial relaxation are explained. Experimental results for the discussed loads are introduced, which have led to satisfactory agreement between theory and experiment. (orig./MM).

1987-01-01

447

Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress  

International Nuclear Information System (INIS)

The program introduced here for determining and describing the multi-axial creep of pipes is based, on the one hand, on the results of the nuclear process heat prototype plant material program and, on the other hand, on the possible load conditions which arise for evaluating accidents or extreme working situations. The basis of a theoretical description of multi-axial creep is the invariant theory in which both the von Mises configuration change hypothesis and the Norton creep law are included. Combined tension and torsion are also considered in detail, the superimposition of cyclic stresses in the tensile threshold area is discussed and cases of partial relaxation are explained. Experimental results for the discussed loads are introduced, which have led to satisfactory agreement between theory and experiment. (orig./MM).

1987-11-27

448

Invariance, groups, and non-uniqueness: The discrete case  

Energy Technology Data Exchange (ETDEWEB)

Lie group methods provide a valuable tool for examininginvariance and non-uniqueness associated with geophysical inverseproblems. The techniques are particularly well suited for the study ofnon-linear inverse problems. Using the infinitesimal generators of thegroup it is possible to move within the null space in an iterativefashion. The key computational step in determining the symmetry groupsassociated with an inverse problem is the singular value decomposition(SVD) of a sparse matrix. I apply the methodology to the eikonal equationand examine the possible solutions associated with a crosswelltomographic experiment. Results from a synthetic test indicate that it ispossible to vary the velocity model significantly and still fit thereference arrival times. the approach is also applied to data fromcorosswell surveys conducted before and after a CO2 injection at the LostHills field in California. The results highlight the fact ...

2005-03-24

449

Interactions at the cofired interface of Ag/Pd electrode and lead-based ferroelectrics  

Energy Technology Data Exchange (ETDEWEB)

In the present study, element interdiffusions at the cofired interface of 9/1 Ag/Pd electrode and lead magnesium niobate (PMN)-based ferroelectrics were investigated using Auger Electron Spectroscopy (AES). Intense interdiffusions at the interface were observed while Ag and Pd could penetrate into the ceramics for about 1 {mu}m. Ag-doping experiments were carried out to further study the effects of Ag diffusion on electrical properties of the ceramics. The results showed that Ag could be incorporated into solid solution of the ceramics as Ag{sup +}. As a whole, the Curie temperature (Tc) and dielectric constant of the ceramics decreased with Ag addition. However, Ag addition had no obvious effect on the insulation resistivity. The results inferred that Ag{sup +} could substitute for Pb{sup 2+} at A site of ABO{sub 3} lattice, thereby oxygen vacancies were generated.

2003-05-25

450

Innovation in technology for the least product price and cost - a new minimum cost relation for reductions during technological learning  

Energy Technology Data Exchange (ETDEWEB)

By analogy with the concepts of human learning, we show and introduce a new method to obtain least product cost and price that includes the effect of innovation and technological learning in manufacturing and production. This key result is a new paradigm instead of the usual economic 'power law' formulation. The new analysis is based on extensive analysis of many technological systems, and is directly related to the presence of learning as experience is accumulated. The results agree with the observed data. By using a consistent basis, the method replaces previous empirical 'power law' descriptions of the technological learning curve with a new 'marginal minimum cost equation' (MCE). (author)

2004-07-01

451

Influence of mass transfer on thermogravimetric analysis of combustion and gasification reactivity of coke  

British Library Electronic Table of Contents (United Kingdom)

Non-isothermal TG/DTG measurements are widely used to determine kinetic parameters of oxidation and gasification of carbons, e.g. by multi-heating rate methods. Thereby it is important to avoid spurious effects due to diffusion limitations. In this work, TG/DTG experiments with activated carbon were conducted under isothermal and non-isothermal conditions. The agreement of the experimental results with results of simulations based on the intrinsic kinetics, pore diffusion and external diffusion in/to the sample (crucible) is very good. The simulations show that mass transfer has an unwanted influence on TG measurements, if the concentration of the gaseous reactant (O2 and CO2) is too low and/or the heating rate is too high. Based on literature data, the simulation was extended to blast fur...

2010-01-01

452

Experimental optimization of a real time fed-batch fermentation process using Markov decision process.  

Science.gov (United States)

This article describes a methodology that implements a Markov decision process (MDP) optimization technique in a real time fed-batch experiment. Biological systems can be better modeled under the stochastic framework and MDP is shown to be a suitable technique for their optimization. A nonlinear input/output model is used to calculate the probability transitions. All elements of the MDP are identified according to physical parameters. Finally, this study compares the results obtained when optimizing ethanol production using the infinite horizon problem, with total expected discount policy, to previous experimental results aimed at optimizing ethanol production using a recombinant Escherichia coli fed-batch cultivation. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 317-327, 1997. PMID:18636490

1997-07-20

453

Evaluation of improvements in the installation of rural underground transmission lines: Final report  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of an investigation into currently used methods for installation of underground high voltage power transmission cable, and offers recommendations for potentially improving these methods. Suggested enhancements cover the emplacement of both high pressure oil filled (HPOPT) pipe type and self contained oil filled (SCOF) cable systems. Cost comparisons of conventionally installed cable systems versus systems using proposed techniques and equipment are developed for a specific site selected for study. The report also documents the test results of laboratory experiments conducted to demonstrate the feasibility of using interference fit pipe couplings in place of welded pipe joints. 10 refs., 31 figs., 15 tabs.

1987-10-01

454

Energy saving in existing buildings. Experiences with 'Therma' buildings. Energieeinsparung im Bestand. Erfahrungen mit den Therma-Bauten  

Energy Technology Data Exchange (ETDEWEB)

A number of buildings dating from the 1950s and 1960s were retrofitted with thermal insulation in order to cut energy consumption. This took place within the building competition 'Therma' nitrated by the Federal Ministry of Regional Planning, Building and Town Planning in 1974. Result at that time were so encouraging that now, 15 years later the results were checked again with special attention to the long-term performance of the thermal insulation measures. Laboratory tests prove that the building materials are still in good condition and that humidity has not increased with age. Cracks in the surface plaster of the compound insulation systems occurred at different frequencies and intensities and usually caused by thermal tensions. (BWI).

1992-04-01

455

Electronic structure, charge distribution and X-ray emission spectra of V_3Si  

International Nuclear Information System (INIS)

Cluster calculations of the electronic structure and charge distribution in V_3Si have been performed using two different molecular orbital methods: a semiempirical LCAO and the MS X#alpha# model. The results are compared with X-ray emission spectra and band structure calculations. An analysis of the calculated electronic distribution reveals a charge transfer from Si-atoms to V-atoms, the additional charge on a V-atom being 0.6e (LCAO) and 0.4e (MS X#alpha# method). The results are in good agreement with experiment, which indicates that the cluster approach is adequate for the description of charge distributions and spectra characteristics of the A-15 compounds. (author).

456

Egg-larval mortality of Pacific herring in Prince William Sound, Alaska, after the Exxon Valdez oil spill  

Energy Technology Data Exchange (ETDEWEB)

Experiments were carried out to test the hypothesis that instantaneous daily rates of egg-larval mortality of Pacific herring were higher at two oil-exposed sites than at two other sites not so exposed. Results showed that egg-larval mortality was twice as great in the oil-exposed areas as in the two non-oiled areas. Larval growth rates were also severely affected; they were about half of those measured in populations from other areas of the north Pacific Ocean. A cautionary note was introduced to the effect that the differences in the egg-larval mortality between oiled and control sites may have been influenced by differences in egg dessication, predation, and wave scouring, hence these results should not be construed as conclusive evidence of oil spill damage. 40 refs., 6 figs.

1996-10-01

457

Effects of linear, ambient wind shear on simulated mammatus-like clouds  

British Library Electronic Table of Contents (United Kingdom)

A suite of numerical experiments is conducted to extend our previous studies to explore the effects of linear, ambient wind shear on simulated mammatus-like clouds. Increasing values of unidirectional shear result in banded cloud bases, and for the strongest shears roll-type quasi-two-dimensional convection results rather than three-dimensional lobe morphology. Two observed soundings were used, and the sounding with a drier, shallower sub-cloud layer appeared to be most strongly affected by the presence of the ambient shear. The drier sounding also had less snow in the mammatus lobes owing to sublimation. Copyright Copyright 2009 Royal Meteorological Society

2009-01-01

458

Effects of boron addition on weldability and high temperature strength properties of Hastelloy alloy XR  

Energy Technology Data Exchange (ETDEWEB)

The effects of boron addition on weldability and high temperature strength properties were investigated for Hastelloy alloy XR used TIG welding process with the filler metals. Four versions of filler metals with different boron contents were used. The results obtained may be summarized as follows: (1) The influence of boron addition on weldability was not observed within the range of the present experiment. (2) The result of chemical analysis for deposited metals showed that boron desorption did not occur during welding. (3) The tensile properties of weldments, particularly in high temperature ductility were raised with increasing boron content. (4) In the creep properties of weldments, creep rupture life increased with increasing boron content under the given stress conditions. (author).

1990-11-01

459

Effects of boron addition on weldability and high temperature strength properties of Hastelloy alloy XR  

International Nuclear Information System (INIS)

The effects of boron addition on weldability and high temperature strength properties were investigated for Hastelloy alloy XR used TIG welding process with the filler metals. Four versions of filler metals with different boron contents were used. The results obtained may be summarized as follows: 1) The influence of boron addition on weldability was not observed within the range of the present experiment. 2) The result of chemical analysis for deposited metals showed that boron desorption did not occur during welding. 3) The tensile properties of weldments, particularly in high temperature ductility were raised with increasing boron content. 4) In the creep properties of weldments, creep rupture life increased with increasing boron content under the given stress conditions. (author).

460

Direct strip casting of magnesium  

Energy Technology Data Exchange (ETDEWEB)

A new interest in magnesium alloys has arisen since light-weight constructions have become more and more attractive. Products that are currently available are mostly cast, forged, and extruded. A cost-effective production of sheet metals will render new perspectives in the design of light-weight constructions. The development of new casting technologies like thin slab casting or strip casting with an in-line rolling process is expected to result in a shorter processing time featuring a high potential of saving energy, time, and cost. Particular attention is paid to the casting process parameters such as casting speed and solidification speed. This article deals with some aspects of a magnesium-adapted single-belt caster. Results of casting experiments and material examination are shown as well as some advices given concerning safety and handling of liquid magnesium. (orig.)

2004-12-01

461

Development of ozone generator by modification of the field distribution  

International Nuclear Information System (INIS)

New methods have been established to enhance the ozone production of the surface discharge arrangement. One method sets the discharge electrode a short distance away from the surface of the dielectric material, whilst another uses a special power supply system resulting in a superimposed discharge. According to the experiments, significant differences have been found in the ozone production capacity of the different arrangements. The characteristics of the electric field distribution of the designs have been calculated using the finite element method for the potential; and the Donor-Cell method for the space charge calculation, and the results have been analysed. A method of analysis has been established for the calculated field characteristics, which provides two index numbers. The reasons are highlighted for the differences in ozone production in relation to the index numbers obtained from the fields' distributions of the ...

2008-12-01

462

Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst. Technical progress report No. 17, 1 November 1993--31 December 1993  

Energy Technology Data Exchange (ETDEWEB)

Very high cobalt catalysts have been prepared on steamed and acid-washed y zeolite. These catalysts are very active. Some of them have proven to be very stable. Additionally, if provisions are made to control the temperature build up on the catalyst bed, low methane selectivities result. Additional work is indicated, for instance, perhaps even higher activity catalysts can result from higher levels of cobalt or changes in the catalyst preparation procedure. Since the issue of whether small amounts of ruthenium can promote the catalyst is not completely resolved, catalyst preparation procedure experiments should continue with ruthenium vs. ruthenium-free catalysts. For instance, different methods of impregnation and/or activation should be investigated.

1994-06-01

463

Convective losses from cavity solar receivers--Comparisons between analytical predictions and experimental results  

Energy Technology Data Exchange (ETDEWEB)

Cavity solar receivers are generally believed to have higher thermal efficiencies than external receivers due to reduced losses. A simple analytical model was presented by the author which indicated that the ability to heat the air inside the cavity often controls the convective loss from cavity receivers. Thus, if the receiver contains a large amount of inactive hot wall area, it can experience a large convective loss. Excellent experimental data from a variety of cavity configurations and orientations have recently become available. These data provided a means of testing and refining the analytical model. In this manuscript, a brief description of the refined model is presented. Emphasis is placed on using available experimental evidence to substantiate the hypothesized mechanisms and assumptions. Detailed comparisons are given between analytical predictions and experimental results. Excellent agreement is obtained, and the important ...

1982-02-01

464

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

465

Comparing dose calculation algorithms for an orthovoltage beam in a bone phantom  

International Nuclear Information System (INIS)

The aim of this work was to compare dose calculation algorithm results at orthovoltage energies for a phantom composed of a bone slab in water. The calculation methods investigated were: no correction, ETAR, Batho, convolution/superposition and Monte Carlo. All algorithms calculated depth dose curves in a water phantom within 4% of experiment. However in the bone phantom, differences of over 40% between the No Correction / ETAR / Batho / Convolution and Monte Carlo results in the 1 cm thick bone slab were observed. These differences are predominantly because the algorithms do not account for the differing atomic number of the bone compared to water The increased dose to bone and the tissue adjacent to the bone interface should be considered when treating with orthovoltage photons. Copyright (1998) Australasian Physical and Engineering Sciences in Medicine

1998-09-01

466

Calculation of the air flow, air quality and the thermal comfort in an operating room. Berekening van de luchtstroming, luchtkwaliteit en het thermisch comfort in een operatiekamer  

Energy Technology Data Exchange (ETDEWEB)

By means of a numerical simulation model (PHOENICS) the air flow and the distribution of the air concentration in an operating room of an hospital have been calculated. Comparisons were made for 11 different conditions (m[sup 3]/h air flow, speed of the air supply in the centre, the middle and outside of the room), of which six cases are discussed in this article, in order to optimize the air flow pattern in the room. The calculations were conducted for the so-called Howorth system. It is shown that the inlet velocity profile with a higher inlet velocity in the center zone of the hood gives the best results. The calculated results were validated by some measurements and experiments with smoke. 7 figs., 2 tabs., 8 refs.

1993-04-01

467

CT colonoscopy with volume rendering. Results and comparison with endoscopy and surgery; Cononscopia con tomografia computerizzata con ricostruzioni di volume: risultati e confronto con endoscopia  

Energy Technology Data Exchange (ETDEWEB)

The paper reports the results of a preliminary experience with volume rendering technique of virtual computerized tomography colonoscopy and compares it with endoscopy and surgery showing its capability in detecting colon and rectal cancers. [Italian] Scopo del lavoro e' riportare l'esperienza personale preliminare nell'uso della colonscopia TC virtuale confrontando i risultati con quelli dell'endoscopia e dei riscontri operatori, dimostrandone l'efficacia nella diagnosi delle malattie tumorali del colon-retto.

1999-09-01

468

C-E critical heat flux. Critical heat flux correlation for C-E fuel assemblies with standard spacer grids. Part 1. Uniform axial power distribution  

International Nuclear Information System (INIS)

The report presents the results of experimental studies conducted to provide a description of the conditions which lead to the occurrence of critical heat flux (CHF), in Combustion Engineering (C-E) fuel assemblies using the C-E standard spacer grid. A CHF correlation is presented which is based on CHF data obtained in tests with electrically heated rod bundles representative of the C-E 14 x 14 and 16 x 16 array fuel assemblies. The results reported are for a uniform axial heat flux distribution. The experiments were conducted in the Medium Pressure Heat Transfer Flow Loop at the Chemical Engineering Research Laboratories at Columbia University.

469

Bladder Injuries During Laparoscopic Orchiopexy: Incidence and Lessons Learned  

British Library Electronic Table of Contents (United Kingdom)

Purpose Laparoscopic orchiopexy is a safe operation. However, the bladder can be injured during creation of the transperitoneal tunnel for the cryptorchid testis. We reviewed our experience with this complication. Materials and Methods We searched the operative notes of patients who had undergone laparoscopic orchiopexy between August 15, 2002 and October 1, 2008, and identified bladder injuries and their treatment. Results A total of 93 patients underwent laparoscopic orchiopexies for 101 undescended testes during the study interval, with 3 procedures resulting in bladder injuries. The 3 operations varied with regard to whether the injury was recognized intraoperatively or postoperatively, and repaired in an open or laparoscopic fashion. Conclusions Bladder injury during laparoscopic orch...

2009-01-01

470

Adsorption Kinetics of Surfactants at Fluid-Fluid Interfaces  

CERN Document Server

We review a new theoretical approach to the kinetics of surfactant adsorption at fluid-fluid interfaces. It yields a more complete description of the kinetics both in the aqueous solution and at the interface, deriving all equations from a free-energy functional. It also provides a general method to calculate dynamic surface tensions. For non-ionic surfactants the results coincide with previous models. Common non-ionic surfactants are shown to undergo diffusion-limited adsorption, in agreement with experiments. Strong electrostatic interactions in salt-free ionic surfactant solutions are found to lead to kinetically limited adsorption. In this case the theory accounts for unusual experimental results which could not be understood using previous approaches. Added salt screens the electrostatic interactions and makes the ionic surfactant adsorption similar to the non-ionic case. The departure from the non-ionic behavior as ...

1997-01-01

471

Absorption of carbon dioxide at high partial pressures in 1-amino-2-propanol aqueous solution. Considerations of thermal effects  

Energy Technology Data Exchange (ETDEWEB)

In the present work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA)), in relation to the thermal effects involved. All experiments were made in a stirred-tank reactor with a plane unbroken gas-liquid interface. The variables considered were the MIPA concentration within the range 0.1--2.0 M and the temperature within the interval 288--308 K. From the results, the authors deduce that the absorption process takes place in the nonisothermal instantaneous regime and propose an equation which not only relates the experimental results of flow density with the initial concentration of amine but at the same time enables the evaluation of the rise in temperature in the gas-liquid interface.

1997-10-01

472

A large solid angle, high stopping power Bragg curve spectrometer for coincidence measurements  

Energy Technology Data Exchange (ETDEWEB)

A large acceptance, high stopping power, Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. The detector design was aided by the results of computer simulations of the electron collection process in the detector, and of the signal processing in the electronics. The signals from the Bragg curve spectrometer are recorded in a waveform digitizer and the Bragg peak height, range, position and pileup rejection information are determined from software analysis of the recorded signals. Factors limiting the performance of the detector are discussed, and results obtained with the detector are ...

1991-09-01

473

A large solid angle, high stopping power Bragg curve spectrometer for coincidence measurements  

International Nuclear Information System (INIS)

A large acceptance, high stopping power, Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. The detector design was aided by the results of computer simulations of the electron collection process in the detector, and of the signal processing in the electronics. The signals from the Bragg curve spectrometer are recorded in a waveform digitizer and the Bragg peak height, range, position and pileup rejection information are determined from software analysis of the recorded signals. Factors limiting the performance of the detector are discussed, and results obtained with the detector are ...

474

A Study on A Semi-Submersible Floating Offshore Wind Energy Conversion System  

Energy Technology Data Exchange (ETDEWEB)

A new semi-submersible floating structure is proposed on which three wind turbine towers are installed. This paper presents a basic characteristic of the wave-induced motion of this semi-submersible floating structure via. numerical computations and 1/150 scaled rigid model experiments in a wave tank. In the numerical computations, nonlinear damping effect due to drag forces modeled by the Morison's formula is considered in the equation of motion, where the linear hydrodynamic forces are obtained from the Green's function model. As a result, the response characteristics around the resonant frequency region were successfully improved. In addition to such basic examination, major results of feasibility studies, including the structural stability for severe wave conditions and the long-term fatigue limit state, are presented for a realistic situation.

2007-07-01

483

Antitumor activity of platinum(II) complexes with histamine and radioiodinated histamine in a transplantable murine adenocarcinoma model  

Energy Technology Data Exchange (ETDEWEB)

Purpose: Antitumor activity of the dichloroplatinum(II)-histamine complexes labeled with I-125 or I-131 was investigated in a transplantable murine adenocarcinoma (MA) model. Methods: The tumor model was obtained in C3H/W female mice after subcutaneous inoculation of the tumor cells derived from the mice bearing a mammary tumor of spontaneous origin. Antitumor activities of the platinum-histamine complexes were investigated in three independent experiments, which differed in applied doses of preparations (PtCl{sub 2}Hist, PtCl{sub 2}[{sup 125}I]Hist, PtCl{sub 2}[{sup 131}I]Hist, PtCl{sub 2}Hist/PtCl{sub 2}[{sup 125}I]Hist and PtCl{sub 2}Hist/PtCl{sub 2}[{sup 131}I]Hist), treatment schedules as well as stages of the disease progress in the animals used. Experiment 1 included long-term, multidose treatment with low single doses (treatment duration 31-32 days; 8-10 doses of ca. 0.25{center_dot}MTD{sub Pt} each). Experiment 2 ...

2008-07-15

484

Study on the effectiveness of some decontamination agents against skin contamination of {sup 137}Cs and {sup 60}Co  

Energy Technology Data Exchange (ETDEWEB)

In order to evaluate the effectiveness of some decontamination agents against skin contamination of {sup 60}Co and {sup 137}Cs, the experiments were carried out in this study. In the experiments, pig skin was used instead of human skin, {sup 60}CoCl{sub 2} and {sup 137}CsCl were used the liquid sources of skin contamination. To examine the effectiveness of decontamination agents, skin decontamination was tried using soup, EDTA, DAERICON which was developed for decontamination of radionuclides on the surface of building structure, and new decontamination agents such as IOCON, TRICON, and CHARCON, which were developed in this study. The absorption of radionuclides through the skin was evaluated by the gamma-ray detection on the surface of sample skin after radionuclides were penetrated into the skin during 16 hour soiling time. The results of this absorption experiment indicated that 11.5% and 3.2% of ...

1998-03-01

485

Study on the effectiveness of some decontamination agents against skin contamination of "1"3"7Cs and "6"0Co  

International Nuclear Information System (INIS)

In order to evaluate the effectiveness of some decontamination agents against skin contamination of "6"0Co and "1"3"7Cs, the experiments were carried out in this study. In the experiments, pig skin was used instead of human skin, "6"0CoCl_2 and "1"3"7CsCl were used the liquid sources of skin contamination. To examine the effectiveness of decontamination agents, skin decontamination was tried using soup, EDTA, DAERICON which was developed for decontamination of radionuclides on the surface of building structure, and new decontamination agents such as IOCON, TRICON, and CHARCON, which were developed in this study. The absorption of radionuclides through the skin was evaluated by the gamma-ray detection on the surface of sample skin after radionuclides were penetrated into the skin during 16 hour soiling time. The results of this absorption experiment indicated that 11.5% and 3.2% of initial amounts of ...

1998-03-01

486

Hybrid functionals and their application to small molecules and solids  

International Nuclear Information System (INIS)

Full text: Hybrid functionals, containing a fraction of the exact exchange, allow for a rather accurate treatment of e.g. small molecules and band gaps in bulk materials. A plane-wave based algorithm was implemented in VASP (Vienna Ab-initio Simulation Package) to accomplish the calculation of the exact exchange. Two functionals including exact exchange are presently available, i.e. the PBE0 (Perdew-BurKEX-Ernzerhof) and the HSE (Heyd-Scuseria-Ernzerhof). A rigorous assessment of the implementation was performed by geometry optimization and calculation of the atomization energies of the G2-1 quantum chemical test set, containing 55 molecules. Excellent agreement compared to corresponding Gaussian 03 data and good agreement with experiment was achieved. The mean absolute error (theory related to experiment) for the atomization energies calculated with the PBE and the PBE0 is 8.6 and 3.7 kcal/mol, respectively. To investigate the properties of ...

2005-09-27

487

Experimental Study of Hypernuclei Electroproduction by High Precision Spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Jlab experiment E01-011, carried out in 2005 in JLab Hall C, is the second generation of the hypernuclear spectroscopy experiments by the (e,e{prime}K{sup +}) reaction. The (e,e{prime}K{sup +}) reaction is complimentary to the associated production reactions (K{sup -},{pi}{sup -}), ({pi}{sup +},K{sup +}) since, due to a larger momentum transfer to a hyperon, excitations of both spin-non-flip and spin-flip states are possible. The experiment uses high quality and continuous primary electron beam to produce neutron rich hypernuclei on various targets by the electroproduction. The experimental setup consists of splitter magnet, high resolution kaon spectrometer (HKS) and electron spectrometer (Enge) implemented in new configuration, the so called 'Tilt Method'. Production data was taken on multiple targets: CH{sub 2}, {sup 6}Li, {sup 7}Li, {sup 9}Be, {sup 10}B, {sup 12}C and {sup 28}Si. In present study the ...

2009-12-01

488

Design of a closed 4 MW spallation target module with heat removal system for an ADS system  

International Nuclear Information System (INIS)

At the Forschungszentrum Karlsruhe the HGF Strategy Fund project entitled 'Innovative Technology to Reduce Radiotoxicity' is performed which delivers an essential scientific contribution to the application oriented fundamental research for Accelerator Driven Systems (ADS). The addressed topics are in the areas of heavy liquid metal technology, thermalhydraulics and materials / corrosion. An ADS consists of three main components: an proton accelerator, a spallation target and a subcritical blanket. The strategic objective of an ADS is the transmutation of long-lived radioactive waste (plutonium, minor actinides and long-lived fission products) into short-lived isotopes or stable elements, thus closing the fuel cycle. The objective of one task of the HGF Strategy Fund Project is the numerical calculation of a closed spallation target module. In a consequent next step such a spallation target can be experimentally investigated at IKET and the numerical results can be ...

489

Chemistry of transuranium elements and compounds  

International Nuclear Information System (INIS)

Studies are made in this program to enhance our understanding of the role of 5f electrons in chemical bonding. Most of our studies on the macroscopic scale emphasize certain isotopes available from the National Transplutonium Production Program centered at HFIR/TRU -namely, _9_6"2"4"8Cm, _9_7"2"4"9Bk, _9_8"2"4"9Cf, _9_9"2"5"3Es, and _9_9"2"5"4Es. Particular classes of compounds, such as hydrides, chalcogenides, and pnictides are often selected for study on the basis of their utility in bringing out significant chemical differences between the lanthanides and the actinides. High temperature/high pressure experiments on actinide metals and compounds reveal characteristics about the degree of 5f electron localization as a function of atomic number in the series. Magnetic properties of metals and compounds are investigated using ultra-sensitive methods and hydration numbers of ions in solution are investigated by neutron scattering at HFIR. As a ...

1986-05-01

490

Boil-off experiments with the EIR-NEPTUN Facility: Analysis and code assessment overview report  

International Nuclear Information System (INIS)

The NEPTUN data discussed in this report are from core uncovery (boil-off) experiments designed to investigate the mixture level decrease and the heat up of the fuel rod simulators above the mixture level for conditions simulating core boil-off for a nuclear reactor under small break loss-of-coolant accident conditions. The first series of experiments performed in the NEPTUN test facility consisted of ten boil-off (uncovery) and one adiabatic heat-up tests. In these tests three parameters were varied: rod power, system pressure and initial coolant subcooling. The NEPTUN experiments showed that the external surface thermocouples do not cause a significant cooling influence in the rods to which they are attached under boil-off conditions. The reflooding tests performed later on indicated that the external surface thermocouples have some effect during reflooding for NEPTUN electrically heated rod bundle. Peak cladding ...

491

An Investigation of the Coastal Circulations and Aerosol Transport in the Arabian Gulf region during Unified Aerosol Experiment (2004)  

Science.gov (United States)

An observational and modeling study was performed over the Arabian Gulf region to investigate the coastal circulations and aerosol transport in the area. Climatological data and observations from the United Arab Emirates' Unified Aerosol Experiment were used to develop a better understanding of the complex meteorological processes in the Arabian Gulf region. Climatological data suggests that sea breezes occur on more than 77 percent of days in all months of the year and land breezes occur on more than 70 percent of the days. The occurrence of the sea and land breeze circulations are higher (90-99 percent) during the summer months when large-scale weather patterns are quiescent. Measurements of aerosol concentrations taken during the Unified Aerosol Experiment(2004) experiment are used to investigate aerosols, namely dust, transported in the Arabian Gulf region. Vertical profiles of dust concentration along with vertical ...

2005-12-01

492

The Last Unknown Neutrino Mixing Angle $\\theta_{13}$ and the Daya Bay Experiment  

CERN Document Server

The Last Unknown Neutrino Mixing Angle $\\theta_{13}$ and the Daya Bay Experiment

2006-01-01

493

Global Tropospheric Experiment (GTE) PEM Tropics Summary  

Science.gov (United States)

Apr 3, 2002 ... Global Tropospheric Experiment (GTE) PEM Tropics Summary.

494

Multiaxial, isothermal and thermocyclic fatigue in the austenitic steel 1.4909; Isotherm-mehrachsige und thermozyklische Ermuedung des austenitischen Stahles 1.4909  

Energy Technology Data Exchange (ETDEWEB)

The paper discusses multiaxial, isothermal and thermocyclic experiments with tubes made of the austenitic steel 1.4909 (AISI 316 L(N)). The thermocyclic stress is induced by periodic, inductive heating of the tube outer wall and simultaneous, continuous water cooling of the inner wall. Temperature gradients above 100 K/mm are measured, which cause fatigue cracking, predominantly in the inner wall. The experiments with the isothermally stressed tube specimens are intended to simulate the equi-biaxial stress conditions that are typical of the thermocyclic stress regime. This stress regime is created by superimposed longitudinal stress (tension/compression), and circumferential stress (internal/external compression). A novel test bench was realised specifically for the experiments. The paper explains design, operation, and measuring techniques, especially of the circumferential strain measurements. The measured ...

1993-12-31

495

Shape isomers: Mean-field description and beyond  

Energy Technology Data Exchange (ETDEWEB)

Nuclear Hartree-Fock (HF) + BCS calculations have led to predictions of shape isomerism in isotopes of Pt, Hg and Os nuclei. These have been confirmed through the observation of superdeformed rotational bands in {sup 190,{hor ellipsis},194}Hg. Encouraged by these measurements and similar observations in {sup 194}Pb, we have extended these calculations to a wide range of contiguous nuclei. These HF results, for {sup 192,194}Pt, {sup 190,{hor ellipsis},198}Hg and {sup 194}Pb, have been employed in a Generator Coordinate Method (GCM) calculation utilizing the quadrupole deformation as the generating variable. The resulting spectra confirm the conclusions drawn from the HF results and agree with those experiments which have been performed. Adding a phenomenological assumption for the moments of inertia of our GCM states, we can construct the radiative transitions within and out of the superdeformed band. ...

1990-11-19

496

Mechanical properties of excimer laser modified titanium surfaces  

Energy Technology Data Exchange (ETDEWEB)

Excimer laser processing enables both thermally-driven transformations and the incorporation of solutes into the surface of materials through melting and diffusional mixing. We have examined the effect of excimer laser processing on the microstructure and surface mechanical properties of titanium alloys. Changes in the surface hardness due to laser processing were studied using a Nanoindenter [trademark]. Alloying experiments using both mixing of evaporated surface layers of boron and laser gas alloying in air and in nitrogen all result in changes in the surface hardness of the material. Alloying with boron results in an amorphous surface which is somewhat harder than the as polished surface. Laser processing in air and pure nitrogen results in incorporation of oxygen and nitrogen and the development of fine ([approximately] 50 nm) precipitates of TiO and TiN respectively. Substantial increases in ...

1993-01-01

497

Experimental investigation of the thermal contact resistance of a space-use deep groove ball bearing. Uchuyo fukamizo tamajikuukenai no sesshoku netsu teiko ni kansuru jikkenteki kento  

Energy Technology Data Exchange (ETDEWEB)

The thermal contact resistance between balls and inner and outer rings of thermally steady space-use deep groove ball bearings was studied experimentally to verify the validity of the previously proposed calculation method for the resistance. The 440C stainless steel single row bearing was used for measuring its steady state temperature distributions in a vacuum environment under axial, radial and combined load conditions. As a result, the experimental results of the resistance well agreed with calculated ones under each load condition resulting in the sufficient validity at nearly the same surface roughness. It was necessary to apply a static equivalent radial load to calculation under the combined load that a contact angle is larger than the angle of resultant force dependent on both load components. In experiments under only radial load, measurement of outer ring temperatures was ...

1992-12-05

498

CT colonography: interpretative performance in a non-academic environment  

Energy Technology Data Exchange (ETDEWEB)

Aim: To investigate interpretative accuracy and reporting time for radiologists performing computed tomography (CT) colonography in day-to-day non-academic clinical practice. Materials and methods: Thirteen radiologists from seven centres, who were reporting CT colonography in non-academic daily clinical practice, interpreted a dataset of 15 colonoscopically validated cases in a controlled environment. Ten cases had either a cancer or polyp >10 mm; one case had a medium polyp and four were normal. Correct case categorization and interpretation times were compared using analysis of variance to aggregated results obtained from both experienced observers and observers recently trained using 50 cases, working in an academic environment. The effect of experience was determined using Spearman's rank correlation. Results: Individual accuracy was highly variable, range 53% (95% CI 27-79%) to 93% (95% CI 68-100%). ...

2007-05-15