WorldWideScience
1

Galaxy Cluster Environments of Radio Sources  

CERN Document Server

Using the Sloan Digital Sky Survey (SDSS) and the FIRST (Faint Images of the Radio Sky at Twenty Centimeters) catalogs, we examined the optical environments around double-lobed radio sources. Previous studies have shown that multi-component radio sources exhibiting some degree of bending between components are likely to be found in galaxy clusters. Often this radio emission is associated with a cD-type galaxy at the center of a cluster. We cross-correlated the SDSS with the FIRST catalog and measured the richness of the cluster environments surrounding both bent and straight multi-component sources. This led to the discovery and classification of a large number of galaxy clusters out to a redshift of z ~ 0.5. We divided our sample into smaller subgroups based on their optical and radio properties. We find that FR I radio sources are more ...

2010-01-01

2

A peculiar distribution of radial velocities of faint radio-galaxies with 13.0<=msub(corr)<=15.5  

International Nuclear Information System (INIS)

A sample of 41 radio-galaxies with 13.0<=msub(corr)<=15.5 has been analyzed to test the angular redshift anisotropy discovered on Sc I galaxies by Rubin, Rubin and Ford (1973). The sample does not present their anisotropy but contains an even more curious distribution of radial velocities which suggests that the Rubin-Ford effect results from an anomalous redshift of light when it travels through clusters of galaxies. (Auth.).

3

Ionized gas and radio emission in the barred Seyfert galaxy NGC 5728  

International Nuclear Information System (INIS)

This paper reports extensive new optical and radio observations of NGC 5728, emphasizing the central regions. Deep photographs revealing detail in the faint spiral arms are briefly discussed. Broad-band UBV CCD images obtained to examine the colors of the stellar populations that comprise the bar and central ring are presented. The velocity field and emission maps obtained from imaging spectroscopic measurements in the H-alpha emission line are discussed. Conventional long-slit spectra covering the ionized gas in the nuclear region are described. Detailed maps of the radio emission in the central regions of NGC 5728 are presented. These combined data provide considerable evidence for the inflow of gas into the nuclear region, in response to the nonaxisymmetric gravitational potential of the bar. The possible relation of this phenomenon to the Seyfert nature of NGC 5728 is also considered. 48 references.

4

Faint envelopes of galaxies  

International Nuclear Information System (INIS)

(Jun 1974). United States Kormendy, J. Hale Observatories, Pasadena,

5

A MODEL OF THE SPECTRAL EVOLUTION OF PULSAR WIND NEBULAE  

International Nuclear Information System (INIS)

We study the spectral evolution of pulsar wind nebulae (PWNe) taking into account the energy injected when they are young. We model the evolution of the magnetic field inside a uniformly expanding PWN. Considering time-dependent injection from the pulsar and coolings by radiative and adiabatic losses, we solve the evolution of the particle distribution function. The model is calibrated by fitting the calculated spectrum to the observations of the Crab Nebula at an age of a thousand years. The spectral evolution of the Crab Nebula in our model shows that the flux ratio of TeV #gamma#-rays to X-rays increases with time, which implies that old PWNe are faint in X-rays, but not in TeV #gamma#-rays. The increase of this ratio is because the magnetic field decreases with time and is not because the X-ray emitting particles are cooled more rapidly than the TeV #gamma#-ray emitting particles. Our spectral evolution model matches the observed rate of the ...

2010-06-01

6

Radiation protection - an overview of the concept for radiation protection at work and the concept for environmental radiation protection  

International Nuclear Information System (INIS)

This book gives an overview of the entire field of radiation protection with the subject areas radioactivity, X-rays, UV radiation, laser beams and high-frequency electromagnetic fields. It deals graphically with the most important physical notions, the incidence, origin, properties and biological effects of types of radiation, administrative and practical protection measures and the code of rules governing them. Apart from fundamentals of radiation protection the emphasis on the following: natural radiation exposure, radiation exposure to radon, disaster relief plans in the environment of nuclear plant, the precautionary radiation protection system evolved after Chernobyl, radiation exposure through UV radiation devices, radio, RF communication, radar, microwave ovens and high-voltage transmission lines as well as computer work-places. (orig.).

1993-01-01

7

Applied geodesy  

Energy Technology Data Exchange (ETDEWEB)

This volume is based on the proceedings of the CERN Accelerator School's course on Applied Geodesy for Particle Accelerators held in April 1986. The purpose was to record and disseminate the knowledge gained in recent years on the geodesy of accelerators and other large systems. The latest methods for positioning equipment to sub-millimetric accuracy in deep underground tunnels several tens of kilometers long are described, as well as such sophisticated techniques as the Navstar Global Positioning System and the Terrameter. Automation of better known instruments such as the gyroscope and Distinvar is also treated along with the highly evolved treatment of components in a modern accelerator. Use of the methods described can be of great benefit in many areas of research and industrial geodesy such as surveying, nautical and aeronautical engineering, astronomical radio-interferometry, metrology of large components, deformation studies, ...

1987-01-01

8

Toward the Creation of the World's Smallest Radio  

Science.gov (United States)

... 4. TITLE AND SUBTITLE Toward the Creation of the World's Smallest Radio 5a. ... Toward the Creation of the World's Smallest Radio ...

2011-05-15

9

LAMBDA - IRAS Faint Source Survey Plates - LAMBDA - NASA  

Science.gov (United States)

Apr 18, 2008 ... The FSS was produced by point-source filtering the individual detector data ... a 1-sigma noise map; and a coverage map giving the count of ...

11

Influence of the Alfven wave spectrum on the scrape-off layer of the TCA tokamak  

International Nuclear Information System (INIS)

The study of the scrape-off layer (SOL) during Alfven wave heating may lead to a better understanding of the antenna-plasma interaction. The scrape-off layer of the TCA tokamak has been widely investigated by means of Langmuir probes. The aim of this work is to present measurements on the influence of the Alfven wave spectrum on the scrape-off layer. These experiments have shown that the plasma boundary layer is strongly affected by the wave field, in particular the ion saturation current and the floating potential. In TCA, as the spectrum evolves due to a density rise, the passage of the Alfven continua and their associated eigenmodes, the Discrete Alfven Wave (DAW) induces a strong depletion in the edge density of up to 70% during the continuum part and a density increase during the crossing of an eigenmode. The floating potential becomes negative during the continua and even more negative crossing the eigenmodes. In case of MHD mode activity, this behaviour ...

1988-05-01

12

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

CERN Document Server

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

2007-01-01

14

Preliminary Design of ARIES-Devasthal Faint Object Spectrograph and Camera  

CERN Document Server

We present here the preliminary design of ARIES-Devasthal Faint Object Spectrograph and Camera (ADFOSC), which is a multi-mode instrument for both imaging and spectroscopy. ADFOSC is the first-generation instrument to be mounted at the axial port of the Cassegrain focus on our new 3.6m optical telescope to be installed at Devasthal, Nainital. The main design goals of the instrument are : the instrument will have capability of broad- and narrow-band imaging, low-medium resolution spectroscopy, and imaging polarimetry. The operating wavelength range will be from 360 to 1000 nm and the instrument will have remote-control capability.

2009-01-01

15

On The Parent Population of Radio Galaxies and the FR I--II Dichotomy  

CERN Document Server

The possibility of radio galaxies being random sample of otherwise normal elliptical galaxies is tested. Starting with the observed optical luminosity functions for elliptical galaxies, it is shown that the probability of an elliptical forming a radio source is a continuous, increasing function of optical luminosity, precisely proportional to square of the optical luminosity of the galaxy. Once the probability function is fixed, the luminosity function of normal elliptical galaxies is used as input for Monte Carlo simulations that reproduce the distribution of radio galaxies in the radio-optical luminosity plane. Our results show that radio galaxies are luminosity biased, but otherwise random sample of elliptical galaxies. This unified view of radio and non-radio ellipticals also explains the well known difference of 0.5 mag in average ...

2001-01-01

16

Extended radio emission in MOJAVE Blazars: Challenges to Unification  

CERN Document Server

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

2010-01-01

17

Cataclysmic Variables and a Candidate Helium White Dwarf in the Globular Cluster NGC 6397  

CERN Document Server

We have used HST/FOS to study faint UV stars in the core of the nearby globular cluster NGC 6397. We confirm the presence of a 4th cataclysmic variable (CV) in NGC 6397 (CV 4), and we use the photometry of Cool et al. (1998) to present evidence that CVs 1--4 all have faint disks and probably low accretion rates. By combining these results with new UV spectra of CV 1 and the published spectra of Grindlay et al. (1995) we present new evidence that CVs 1--3 may be DQ Her systems, and we show that CV 4 may either be a dwarf nova or another magnetic system. Another possibility is that the CVs could be old novae in hibernation between nova eruptions. We also present the first spectrum of a member of a new class of UV bright stars in NGC 6397. These faint, hot stars do not vary, unlike the CVs, and are thus denoted as ``non-flickerers'' (NFs). Like the CVs, their spatial concentration is strongly concentrated toward the cluster ...

1999-01-01

18

Survey of Cognitive Radio Techniques in Wireless Network  

CERN Document Server

In this report, I surveyed the cognitive radio technique in wireless networks. Researched several kinds of cognitive techniques about their advantages and disadvantages.

2011-01-01

19

A Study on the Photometric Redshifts of Faint Blue Galaxies in CDFS  

British Library Electronic Table of Contents (United Kingdom)

From the COMBO-17 digital sky survey data, 1,231 faint blue galaxies with photometric redshifts of 0.1

2011-01-01

20

Choice and meaning in the quantum universe  

Energy Technology Data Exchange (ETDEWEB)

This report discusses whether the events that occur in the universe evolve deterministicly or randomly or both. (LSP).

1992-05-22

21

Searches for Fast Radio Transients  

CERN Document Server

We discuss optimal detection of fast radio transients from astrophysical objects while taking into account the effects of propagation through intervening ionized media, including dispersion, scattering and scintillation.Our analysis applies to the giant-pulse phenomenon exhibited by some pulsars, for which we show examples, and to radio pulses from other astrophysical sources, such as prompt radio emission from gamma-ray burst sources and modulated signals from extra-terrestrial civilizations.

2003-01-01

23

Spectroscopic ages and metallicities of galaxies  

CERN Document Server

Dwarf galaxies are generally faint. To derive their age and metallicity distributions, it is critical to optimize the use of any collected photon. Koleva et al., using full spectrum fitting, have found strong population gradients in some dwarf elliptical galaxies. Here, we show that the population profiles derived with this method are consistent and more precise than those obtained with spectrophotometric indices. This allows studying fainter objects in less telescope time.

2011-01-01

24

On The Parent Population of Radio Galaxies and the FRI - FRII Dichotomy  

CERN Document Server

We test the hypothesis that radio galaxies are a random subset of otherwise normal elliptical galaxies. Starting with the observed optical luminosity functions for elliptical galaxies, we show that the probability of an elliptical forming a radio source is a continuous, increasing function of optical luminosity, proportional to L squared. With this probability function and the luminosity function of normal elliptical galaxies as input to Monte Carlo simulations, we reproduce the observed distribution of radio galaxies in the radio-optical luminosity plane. Our results show that radio galaxies are a luminosity-biased but otherwise random sample of elliptical galaxies. This unified view of radio-loud and radio-quiet ellipticals also explains the well known difference of ~0.5 mag in average optical luminosity between FRI and FRII ...

2001-01-01

25

Cold gas & mergers: fundamental difference in HI properties of different types of radio galaxies?  

CERN Document Server

We present results of a study of large-scale neutral hydrogen (HI) gas in nearby radio galaxies. We find that the early-type host galaxies of different types of radio sources (compact, FR-I and FR-II) appear to contain fundamentally different large-scale HI properties: enormous regular rotating disks and rings are present around the host galaxies of a significant fraction of low power compact radio sources, while no large-scale HI is detected in low power, edge-darkened FR-I radio galaxies. Preliminary results of a study of nearby powerful, edge-brightened FR-II radio galaxies show that these systems generally contain significant amounts of large-scale HI, often distributed in tail- or bridge-like structures, indicative of a recent galaxy merger or collision. Our results suggest that different types of radio galaxies may have a different formation history, which ...

2008-01-01

26

Markets and commercialization scenarios for emerging fuel cells in evolving electricity markets  

Energy Technology Data Exchange (ETDEWEB)

Electricity markets in the United States are undergoing unprecedented structural changes as a result of the confluence of regulatory, competitive, and technological forces. This paper introduces these structural changes and forces and discuss the implications, markets and commercialization scenarios for emerging fuel cells in evolving US electricity markets.

1996-12-31

27

A study in molecular contingency: glutamine phosphoribosylpyrophosphate amidotransferase is a promiscuous and evolvable phosphoribosylanthranilate isomerase  

UK PubMed Central (United Kingdom)

SummaryThe prevalence of paralogous enzymes implies that novel catalytic functions can evolve on preexisting protein scaffolds. The weak secondary activities of proteins, which...Full Text Available

2008-03-21

28

The Sustainment Management Support Project  

Science.gov (United States)

... due to the evolving nature of the Strategy Maps and the changing priority roles, it was decided not to link the SMSP directly with any Strategic Plans. ...

2010-09-01

29

Mass: Evolving Tool of the US Operational Artist  

Science.gov (United States)

... ire examples of successive operations, as are the breakout operations GOODWOOD and COBRA. Also, for the first time, ...

1993-05-14

30

In the News...  

Science.gov (United States)

"Ejections. "Massive Star Evolution. "Binary Star Evolution ..... Binary Star Evolution. Stars in binary systems evolve individually and together ...

31

In The News ... - NASA  

Science.gov (United States)

Binary Star Evolution. Stars in binary systems evolve individually and together. " individually: evolution follows normal progression based on ...

32

Psychometric evaluation of a radio electric auricular treatment for stress related disorders: a double-blinded, placebo-controlled controlled pilot study  

UK PubMed Central (United Kingdom)

BackgroundThe aim of this double-blind randomized study is to test the efficacy of a radio electric stimulator device using an auricular reflex therapy protocol for stress-related...Full Text Available

33

Electromagnetic fields, pacemakers and defibrillators; Champs electromagnetiques, cardiostimulateurs et defibrillateurs  

Energy Technology Data Exchange (ETDEWEB)

Presentation of electromagnetic sources constituted by various radio transmitters contributing to different radio communication services in the environment. Results of a measures campaign to assess the electromagnetic field in the close neighbourhood of various stations. Analysis by frequency domains. (author)

2004-07-01

34

STUDY AND MODIFICATION OF CONVECTIVE STORMS  

Science.gov (United States)

... small water or ice particles by impaction ... flight recording; principally the hydrometeor charge unit ... capability of directing aircraft movements by radio ...

1963-06-30

35

Neutrinos from flat-spectrum radio quasars  

Science.gov (United States)

The GRO observation (Hartman et al., 1992) of a very strong flux of gamma rays with an energy index

1992-01-01

36

Chromosomal damage in human lymphocytes from radio-isotope therapy  

International Nuclear Information System (INIS)

(Dec 1973). United Kingdom Stevenson, AC Medical Research Council, Oxford

37

Cores of early-type galaxies - the nature of dwarf spheroidal galaxies  

International Nuclear Information System (INIS)

The characteristics and evolution of dwarf spheroidal galaxies (DSGs) are modeled on the basis of high-resolution CCD photometry obtained with the Canada-France-Hawaii telescope and reported by Kormendy (1986). The data and the results of core-parameter correlation studies are presented in extensive graphs and discussed. It is inferred that at least some DSGs are formed by the stripping of gas from dwarf spiral and irregular galaxies, although internal gas processes may also be important. The hypothesis that DSGs represent the faint end of the elliptical-galaxy sequence appears to be ruled out. 50 references.

38

An Apparent Hard X-ray Decline of CH Cygni  

CERN Document Server

CH Cygni is a symbiotic star consisting of an M giant and an accreting white dwarf, which is known to be a highly variable X-ray source with a complex, two-component, spectra. Here we report on two Suzaku observations of CH Cyg, taken in 2006 January and May, during which the system was seen to be in a soft X-ray bright, hard X-ray faint state. Based on the extraordinary strength of the 6.4 keV fluorescent Fe K-alpha line, we show that the hard X-rays observed with Suzaku are dominated by scattering.

2006-01-01

39

Heterophyle antibodies causing false positive radio-immunoassay results a case report  

International Nuclear Information System (INIS)

A case report of falsely elevated serum hormone values measured by radio-immunoassay (RIA) is described. The radio-immunoassays concerned have a first antibody raised in rabbits and mostly a separation technique based on a second antibody-solid phase system. The presence of heterophyle (anti-rabbit) antibodies in patients' serum is proved.

40

Fault prediction on high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

The prediction of faults on high voltage transmission lines requires the detection of incipient faults, which is implemented by detection of the radio noise due to contaminated insulators, insulation deterioration, and improver connections. It is shown that the radio noise due to incipient faults is separable and identifiable from normal transmission line radio noise, hence faults can be predicted.

1982-12-01

41

Radio and television interference caused by corona discharges from high-voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions ...

1996-11-01

42

Radio and television interference caused by corona discharges from high-voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions ...

1995-10-01

43

Radio and television interference caused by corona discharges from high-voltage transmission lines  

International Nuclear Information System (INIS)

Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions ...

1996-04-09

44

Fermi pulsar revolution  

CERN Document Server

2009 has been an extraordinary year for gamma-ray pulsar astronomy and 2010 promises to be equally good. Not only have we registered an extraordinary increase in the number of pulsars detected in gamma rays, but we have also witnessed the birth of new sub-families: first of all, the radio-quiet gamma pulsars and later an ever growing number of millisecond pulsars, a real surprise. We started with a sample of 7 gamma-ray emitting neutron stars (6 radio pulsars and Geminga) and now the Fermi-LAT harvest encompasses 24 "Geminga-like" new gamma-ray pulsars, a dozen millisecond pulsars and about thirty radio pulsars. Moreover, radio searches targeted to LAT unidentified sources yielded 18 new radio millisecond pulsars, several of which have been already detected also in gamma rays. Thus, currently the family of gamma-ray emitting neutron stars seems to be evenly divided between classical ...

2010-01-01

45

Weak and Failing States: Evolving Security Threats and US ...  

Science.gov (United States)

... has confirmed at least one instance of this: in 2005, Tanzanian customs officials intercepted a shipment that contained a yellow cake-filled barrel ...

2008-08-28

46

Skin as an endocrine organ: implications for its function  

UK PubMed Central (United Kingdom)

Described as the body's largest organ, the skin is strategically located at the interface with the external environment where it has evolved to detect, integrate and respond to a diverse range...Full Text Available

2008-06-01

47

Pseudomonas aeruginosa Virulence and Therapy: Evolving Translational Strategies  

UK PubMed Central (United Kingdom)

Structured abstractObjectiveAlthough most reviews of Pseudomonas aeruginosa therapeutics focus on antibiotics currently in use or...Full Text Available

2009-05-01

48

PPT - AstroGravS - NASA  

Science.gov (United States)

Form as the end result of massive star evolution; Type II supernova: collapse of iron core in highly evolved massive star; outer regions blasted away in ...

49

NASA Direct! - Kennedy Space Center - Home - NASA  

Science.gov (United States)

Aug 21, 2003 ... Her research interests have included hot stars, colliding stellar winds, binary star evolution and evolved stellar companions. ...

50

Introduction & Overview to Symposium 240: Binary Stars as ...  

Science.gov (United States)

... CVn) consisting of a dM3 star and a cool white dwarf that must have evolved through the common-envelope stage of binary star evolution (Else van ...

2011-05-14

51

Influence: Maximizing Effects to Create Long-Term Stability  

Science.gov (United States)

... WHS- Washington Headquarters Service. ... The dynamic Joint Special Operations Task Force -- Philippines (JSOTF-P) has evolved and ...

2010-05-03

52

Indirect resin composites  

UK PubMed Central (United Kingdom)

Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth...Full Text Available

2010-10-01

53

Fractionated stereotactic radiotherapy in the treatment of pituitary macroadenomas  

UK PubMed Central (United Kingdom)

BackgroundThe use of fractionated stereotactic radiotherapy (fsrt) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance....Full Text Available

2008-12-01

55

FIRST Workshop Presentation Abstract: Circumstellar Matter Around ...  

Science.gov (United States)

and the implications for massive star evolution. In recent years, the complex nature of the circumstellar regions of evolved massive stars has become apparent. ...

56

Analysis of codon usage and nucleotide composition bias in polioviruses  

UK PubMed Central (United Kingdom)

BackgroundPoliovirus, the causative agent of poliomyelitis, is a human enterovirus and a member of the family of Picornaviridae and among the most rapidly evolving viruses known....Full Text Available

57

Aging in Language Dynamics  

UK PubMed Central (United Kingdom)

Human languages evolve continuously, and a puzzling problem is how to reconcile the apparent robustness of most of the deep linguistic structures we use with the evidence that they undergo possibly...Full Text Available

58

Adaptive Radiation for Lung Cancer  

UK PubMed Central (United Kingdom)

The challenges of lung cancer radiotherapy are intra/inter-fraction tumor/organ anatomy/motion changes and the need to spare surrounding critical structures. Evolving radiotherapy technologies, such...Full Text Available

2011-01-01

59

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

CERN Document Server

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

2010-01-01

60

Terms Beginning With \\  

Wastenet

... Microwaves, radio waves, and low-frequency electromagnetic fields from high-voltage transmission lines . Non-Methane Hydrocarbon (NMHC): The sum of all hydrocarbon air ...

61

Solar-Geophysical Data Number 438, February 1981. Part 1 (prompt reports). Data for January 1981, December 1980 and late data  

Energy Technology Data Exchange (ETDEWEB)

Contents include: index for 1970-1980; January 1981 data -- alert periods, daily solar indices, solar flares, solar radio emission, coronal holes, inferred interplanetary magnetic field polarities, mean solar magnetic field, spacecraft observations, December 1980 data -- daily solar-activity centers, sudden ionospheric disturbances, spacecraft observations, solar radio emission, cosmic rays, geomagnetic indices, radio-propagation indices; late data -- solar radio emission November, December 1980, spacecraft observations November 1980, cosmic rays, Huancayo Oct 1980 -- climax, alert, Deep River Nov 1980.

1981-02-01

62

NRAO: Press Releases  

Science.gov (United States)

Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...

2011-10-09

63

Modeling the AIM-9 Sidewinder Repair Line through Discrete ...  

Science.gov (United States)

... of electronic systems (satellite terminals, radio and ... helps organizations investigate the stochastic nature of ... cycle time, maximum queue lengths, and ...

2009-06-01

64

Hypoxia and Magnetic Therapy for Personnel Radiation Protection  

International Science & Technology Center (ISTC)

Development of Portable Normobaric Hypoxia and Pulsed Magnetic Field Firmware System for Enhancement of Radio- and Non-specific Resistance in Workers of Environmentally Hazardous Industries

65

Deep Space Probe Science Experiment  

Science.gov (United States)

Briefly, 48 MOS microparticle sensors (essentially the same as those flown on .... at the Naval Research Lab to interpret the polarization of the incoming radio .... Adapter Satellite, to be published in Journal of Spacecraft and Rockets, 1994. ...

66

DSN Radio Science ... - InterPlanetary Network (IPN) Progress Report  

Science.gov (United States)

tions, final noise-power spectral density measurements were made. These measurements of the noise-power spectral density were not the desired phase- noise ...

67

Battle Management Command and Control (BMC2) Human ...  

Science.gov (United States)

... For communication systems that employ spatial audio technology to separate intercom and/or radio channels, configurations of the spatial ...

2005-06-01

68

The kinematics of coronal mass ejections using multiscale methods  

CERN Document Server

The diffuse morphology and transient nature of coronal mass ejections (CMEs) make them difficult to identify and track using traditional image processing techniques. We apply multiscale methods to enhance the visibility of the faint CME front. This enables an ellipse characterisation to objectively study the changing morphology and kinematics of a sample of events imaged by the Large Angle Spectrometric Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO) and the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) onboard the Solar Terrestrial Relations Observatory (STEREO). The accuracy of these methods allows us to test the CMEs for non-constant acceleration and expansion. We exploit the multiscale nature of CMEs to extract structure with a multiscale decomposition, akin to a Canny edge detector. Spatio-temporal filtering highlights the CME front as it propagates in time. We apply an ellipse parameterisation of the front to ...

2009-01-01

69

The Planck-ATCA Coeval Observations project: the faint sample  

British Library Electronic Table of Contents (United Kingdom)

Abstract The Planck-ATCA Coeval Observations (PACO) project collected data between 4.5 and 40 GHz for 482 sources selected within the Australia Telescope 20 GHz (AT20G) catalogue and observed with the Australia Telescope Compact Array. Observations were done almost simultaneously with the-Planck-satellite, in the period between 2009 July and 2010 August. In this paper, we present and discuss the data for the complete sample of 159 sources with-SAT20G > 200-mJy in the South Ecliptic Pole region. The Planck Early Release Compact Source Catalogue (ERCSC) contains 57 of our sources. A comparison between the PACO catalogue and the ERCSC confirms that the reliability of the latter is better than 95-per cent. The missing ERCSC sources are typically associated with the Large Magellanic Cloud, the ...

2011-01-01

70

Variable-speed hydro evolves  

Energy Technology Data Exchange (ETDEWEB)

Success in improving hydropower project efficiency has opened more global markets for variable-speed generator technology. Manufacturers continue to test the markets as the technology evolves. The potential of variable-speed application becomes evident considering that more than 150 pumped storage plants, with a combined capacity exceeding 100,000 MW, are in operation globally.

1993-10-01

71

Vehicle tracking systems  

Energy Technology Data Exchange (ETDEWEB)

Several systems have been developed to accomplish vehicle location. The systems consist of three types: Dead Reckoning, Satellite, and LORAN C. If the information is to be sent back to a central location, some type of radiocommunication system is needed. One can use the existing voice radio or add a radio system just for transmitting the data.

1987-01-01

72

Explore - The Lab - Australian Broadcasting Corporation's Gateway to Science  

Wastenet

...Explore - The Lab - Australian Broadcasting Corporation's Gateway to Science Radio TV Shop News Sport Local Children Science Environment more Topics help Science Home News in Science Features Explore TV & Radio Dr Karl Play Podcasts DNA - The discovery of the double helix structure of DNA completely changed biology and opened up the new field of genetics. The 'backbone of life' has given us the human genome, stem cell research, ...

73

Comparison of three methods of remote metering of electrical energy: Telephone line, fiber optic, and radio packet. Final report, June 1995--August 1995  

Energy Technology Data Exchange (ETDEWEB)

This report deals with the selection of a data communication system for a remote metering system. It covers the following three types of systems: fiber optic, telephone line, and radio packet. It provides a methodology for selecting a communication system for a given remote metering system and a method for comparing costs.

1998-07-01

74

Nonthermal emission from the radio relic of the galaxy cluster A2256  

CERN Document Server

We aim to obtain a consistent description of non-thermal emissions from Abell 2256 and to give a prediction for a gamma-ray emission from this galaxy cluster. Assuming that a radio relic illuminates a localization of an ongoing merger, and that both radio and non-thermal part of hard X-ray emission are due to electron component of cosmic rays filling the relic, we derived from radio and hard X-ray properties of the relic in A2256 the magnetic field strength and number densities for relativistic electrons and protons. Due to the interpretation of the radio relic as a structure formed just where a shock front is, we discuss a gamma-ray emission at the cluster periphery. The estimated strength of the magnetic field in the relic is equal to 0.05 \\muG, while the amplitude of the electron number density varies from 3 x 10^{-4} to 3 x 10^{-5} cm^{-3} (respectively for the relic thickness of 50 to 500 kpc). We ...

2011-01-01

75

Biochemical and molecular genetic approaches on the radioprotective mechanism of natural products  

Energy Technology Data Exchange (ETDEWEB)

We reported the radio-protective effect of DTT. The treatment of DTT increased cell survival after gamma-irradiation, decreased in the frequencies of micronucleus, and reduction in DNA fragmentation and apoptotic cells. Induction of apoptosis after UV-C irradiation was revealed by the changes in the relative cell death, increase in the relative amount of apoptotic cells, and the induction of DNA fragmentation. About 100 medicinal plants were purchased and methanol extract samples were prepared. Radio-protective and radio-sensitizing activities of these samples were screened. Seven samples showed above 20% radio-protective activities: Salvia miltiorrhiza, Areca catechu, Cornus officinalis, Alpiniae officinari rhizoma, Meliae fructus, Alpiniae katsumadaii semen, Betulae cortex. Acanthopanax sessiliflous showed the highest radio-sensitizing effect and 10 other samples revealed moderate ...

1999-04-01

76

The role of gene expression in ecological speciation  

UK PubMed Central (United Kingdom)

Ecological speciation is the process by which barriers to gene flow between populations evolve due to adaptive divergence via natural selection. A relatively unexplored area in ecological speciation...Full Text Available

2010-09-01

77

The elaborate structure of spider silk  

UK PubMed Central (United Kingdom)

Biomaterials, having evolved over millions of years, often exceed man-made materials in their properties. Spider silk is one outstanding fibrous biomaterial which consists almost entirely of large proteins....Full Text Available

2008-10-01

78

The Development and Evolution of Division of Labor and Foraging Specialization in a Social Insect (Apis mellifera L.)  

UK PubMed Central (United Kingdom)

How does complex social behavior evolve? What are the developmental building blocks of division of labor and specialization, the hallmarks of insect societies? Studies have revealed the developmental...Full Text Available

2006-01-01

79

Speciation genetics: current status and evolving approaches  

UK PubMed Central (United Kingdom)

The view of species as entities subjected to natural selection and amenable to change put forth by Charles Darwin and Alfred Wallace laid the conceptual foundation for understanding speciation. Initially...Full Text Available

2010-06-12

80

Parallel Arrays of Geometric Nanowells for Assembling Curtains of DNA with Controlled Lateral Dispersion  

UK PubMed Central (United Kingdom)

The analysis of individual molecules is evolving into an important tool for biological research, and presents conceptually new ways of approaching experimental design strategies. However, more...Full Text Available

2008-10-07

81

NAME=\\  

Wastenet

...this pathway study the following two focus modules (in addition to the six core modules) and carry out a research investigation within this theme: Agricultural Production Systems Considers the type of farming systems that have evolved globally in relation to the prevailing agro-climatic zones, the influences of economic factors ...

82

Minimally invasive surgery for rectal cancer: Are we there yet?  

UK PubMed Central (United Kingdom)

Laparoscopic colon surgery for select cancers is slowly evolving as the standard of care but minimally invasive approaches for rectal cancer have been viewed with significant skepticism. This procedure...Full Text Available

2011-02-21

83

Mesozoic Era of relativistic heavy ion physics and beyond.  

Science.gov (United States)

In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 (times) 10(sup 12) (degrees)K evolved to become today's Universe, the goal of relativistic and ultra-relativistic heavy ion physics is t...

1994-01-01

84

Mathematical model of a utility firm. Final technical report, Part IIB  

Energy Technology Data Exchange (ETDEWEB)

The aim of this project was to develop an understanding of the dynamical processes that evolve within an electric utility firm, and without it. This volume covers organizational dynamics and control, and planning under uncertainty. (DLC)

1983-08-21

85

Maternal effects and range expansion: a key factor in a dynamic process?  

UK PubMed Central (United Kingdom)

Species that depend on ephemeral habitat often evolve distinct dispersal strategies in which the propensity to disperse is closely integrated with a suite of morphological, behavioural and physiological...Full Text Available

2009-04-27

86

Mass spectrometric characterization of high-temperature outgassing of anisotropic pyrolytic boron nitride  

International Nuclear Information System (INIS)

This paper describes a system for fast mass spectrometric characterization of high-temperature outgassing measurements and measuring the total quantity of gas evolved for boron nitride. 2 references, 1 figure, 2 tables.

87

Management of patients with newly diagnosed malignant primary brain tumors with a focus on the evolving role of temozolomide  

UK PubMed Central (United Kingdom)

The prognosis for patients with newly diagnosed malignant gliomas remains poor; however there have been some recent advances in treatment that have generated optimism. Medical management usually includes...Full Text Available

2007-12-01

88

Major evolutionary transitions in ant agriculture  

UK PubMed Central (United Kingdom)

Agriculture is a specialized form of symbiosis that is known to have evolved in only four animal groups: humans, bark beetles, termites, and ants. Here, we reconstruct the major evolutionary transitions...Full Text Available

2008-04-08

89

Life on the edge: carnivore body size variation is all over the place  

UK PubMed Central (United Kingdom)

Evolutionary biologists have long been fascinated by both the ways in which species respond to ecological conditions at the edges of their geographic ranges and the way that species' body sizes evolve...Full Text Available

2009-04-22

90

Inflammatory Bowel Disease in Children, an Evolving Problem in Kuwait  

UK PubMed Central (United Kingdom)

Background/Aims:Inflammatory bowel disease (IBD) was previously thought a rare disease among children in Kuwait since most diarrhea cases were attributed to infections....Full Text Available

2011-09-01

91

How do planetary nebulae evolve  

Energy Technology Data Exchange (ETDEWEB)

This article throws light on an only recently understood but important development of star evolution - that of the occurrence of planetary nebulae. The process is controlled by thermonuclear physics and gravitation and now and again greatly influenced by mass loss.

1982-01-01

92

Evolving hard problems: Generating human genetics datasets with a complex etiology  

UK PubMed Central (United Kingdom)

BackgroundA goal of human genetics is to discover genetic factors that influence individuals' susceptibility to common diseases. Most common diseases are thought to result from the...Full Text Available

93

Duplication and Diversification of the Hypoxia-Inducible IGFBP-1 Gene in Zebrafish  

UK PubMed Central (United Kingdom)

BackgroundGene duplication is the primary force of new gene evolution. Deciphering whether a pair of duplicated genes has evolved divergent functions is often challenging. The zebrafish...Full Text Available

94

Cortical auditory disorders: clinical and psychoacoustic features.  

UK PubMed Central (United Kingdom)

The symptoms of two patients with bilateral cortical auditory lesions evolved from cortical deafness to other auditory syndromes: generalised auditory agnosia, amusia and/or pure word deafness, and...Full Text Available

1988-01-01

95

Coevolution of activating and inhibitory receptors within mammalian carcinoembryonic antigen families  

UK PubMed Central (United Kingdom)

BackgroundMost rapidly evolving gene families are involved in immune responses and reproduction, two biological functions which have been assigned to the carcinoembryonic antigen...Full Text Available

96

Citrate Process Flue Gas Desulfurization Demonstration Plant.  

Science.gov (United States)

At the St. Joe Minerals Corp.'s zinc smelter powerplant, an SO2 emission control program evolved into a cooperative program with the Bureau of Mines for installation and initial operation of a citrate process flue gas desulfurization demonstration plant. ...

1983-01-01

97

Brain transcriptomic analysis in paper wasps identifies genes associated with behaviour across social insect lineages  

UK PubMed Central (United Kingdom)

Comparative sociogenomics has the potential to provide important insights into how social behaviour evolved. We examined brain gene expression profiles of the primitively eusocial wasp Polistes...Full Text Available

2010-07-22

98

Antioxidant Defenses Predict Long-Term Survival in a Passerine Bird  

UK PubMed Central (United Kingdom)

BackgroundNormal and pathological processes entail the production of oxidative substances that can damage biological molecules and harm physiological functions. Organisms have evolved...Full Text Available

99

A genome-wide study of PDZ-domain interactions in C. elegans reveals a high frequency of non-canonical binding  

UK PubMed Central (United Kingdom)

BackgroundProteins may evolve through the recruitment and modification of discrete domains, and in many cases, protein action can be dissected at the domain level. PDZ domains are...Full Text Available

100

Evolution of binary stars in the LMC with helium enrichment  

International Nuclear Information System (INIS)

Recent surveys of supergiants stars in the LMC indicate that the post-main-sequence region of the colour-magnitude diagram is well populated, although numerical evolution of massive stars with normal surface hydrogen indicates to the contrary. Supergiant stars having surface enrichment of helium acquired for example from a previous phase of accretion from a binary companion, however, evolve in a way so that the evolved models and observed data are consistent. We compare the available data with computed evolutionary tracks of massive stars of metallicity relevant to the LMC with and without helium-enriched envelopes and conclude that a large fraction of supergiant stars may occur in binaries. (author).

101

Complex Networks on a Rock Joint  

CERN Document Server

A complex network approach on a rough fracture is developed. In this manner, some hidden metric spaces (similarity measurements) between apertures profiles are set up and a general evolutionary network in two directions (in parallel and perpendicular to the shear direction) is constructed. Also, an algorithm (COmplex Networks on Apertures: CONA) is proposed in which evolving of a network is accomplished using preferential detachments and attachments of edges (based on a competition and game manner) while the number of nodes is fixed. Also, evolving of clustering coefficients and number of edges display similar patterns as well as are appeared in shear stress, hydraulic conductivity and dilation changes, which can be engaged to estimate shear strength distribution of asperities.

2009-01-01

102

Activation of aluminium metal to evolve hydrogen from water  

Energy Technology Data Exchange (ETDEWEB)

The method of aluminium metal activation by liquid eutectics Ga-In (70:30) and Ga-In-Sn-Zn (60:25:10:5) is developed. Subsequent dispersion of the obtained specimens up to a particle size of >0.5mm leads to the drastic interaction of aluminium powder and water with evolving hydrogen. In the present work the oxidation rate of activated aluminium and water is investigated depending on eutectic composition, reaction temperature, and powder particle size. The mechanism of the main eutectic's components influence on the reacting ability of aluminium is discussed. (author)

2008-06-15

103

The impact of solar flares and magnetic storms on humans  

International Nuclear Information System (INIS)

Three classes of solar emanations, namely, photon radiation from solar flares, solar energetic particles, and inhomogeneities in the solar wind that drive magnetic storms, are examined, and their effects on humans and technological systems are discussed. Solar flares may disrupt radio communications in the HF and VLF ranges. Energetic particles pose a special hazard at low-earth orbit and above, where they can penetrate barriers such as spacesuits and aluminum and destroy cells and solid state electronics. Energetic solar particles also influence terrestrial radio waves propagating through polar regions. Magnetic storms may disturb the operation of navigation instruments, power lines and pipelines, and satellites; they give rise to ionospheric storms which affect radio communication at all latitudes. There is also a growing body of evidence that changes in the geomagnetic field affect biological systems. 3 refs.

104

The Nuclear Outflow in NGC 2110  

CERN Document Server

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

2010-01-01

105

Technical evaluation report for the demonstration of radio frequency soil decontamination at Site S-1  

Energy Technology Data Exchange (ETDEWEB)

The Air Force`s Armstrong Laboratory at Tyndall Air Force Base, Florida, has supported the research and development of Radio Frequency Soil Decontamination. Radio frequency soil decontamination is essentially a heat-assisted soil vapor extraction process. Site S-1 at Kelly Air Force Base, San Antonio, Texas, was selected for the demonstration of two patented techniques. The site is a former sump that collected spills and surface run-off from a waste petroleum, oils, and lubricants and solvent storage and transfer area. In 1993, a technique developed by the IIT Research Institute using an array of electrodes placed in the soil was demonstrated. In 1994, a technique developed by KAI Technologies, Inc. using a single applicator placed in a vertical borehole was demonstrated. Approximately 120 tons of soil were heated during each demonstration to a temperature of about 150 degrees Celsius.

1995-04-01

106

Significant Treatment: An Assessment of Issues-Programs List Availability in Missouri Radio Station Public Inspection Files  

British Library Electronic Table of Contents (United Kingdom)

Over the past three decades, rising competition from television and other new media prompted the FCC to ease the responsibilities of radio stations to maintain extensive records of issues programming, while retaining the responsibility of stations to provide ready public access to records. This study investigated the availability of Issues-Programs Lists in nearly 100 Missouri radio station Public Files. One in five randomly sampled stations failed to produce access to Lists upon demand as required under federal law. Noncompliance themes include: Inability to access Public Files within 20 minutes of face-to-face requests; station personnel with limited or no knowledge of Files; denial of access to Files and Lists (i.e., verbal refusals, locked studio doors); and incomplete Files. The rate ...

2007-01-01

107

Jets and accretion processes in Active Galactic Nuclei further clues  

CERN Document Server

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

1996-01-01

108

Cyclic Spectral Analysis of Radio Pulsars  

CERN Document Server

Cyclic spectral analysis is a signal processing technique designed to deal with stochastic signals whose statistics vary periodically with time. Pulsar radio emission is a textbook example of this signal class, known as cyclostationary signals. In this paper, we discuss the application of cyclic spectral analysis methods to pulsar data, and compare the results with the traditional filterbank approaches used for almost all pulsar observations to date. In contrast to standard methods, the cyclic spectrum preserves phase information of the radio signal. This feature allows us to determine the impulse response of the interstellar medium and the intrinsic, unscattered pulse profile directly from a single observation. We illustrate these new analysis techniques using real data from an observation of the millisecond pulsar B1937+21.

2011-01-01

109

X-ray, Optical, and Radio Observations of SN 1999em and SN 1998S  

CERN Document Server

Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first and only Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SN ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate non-radiative interaction of SN ejecta with a power-law density profile (rho \\propto r^{-n} with n ~ 7) with a pre-SN wind with a low mass loss rate of ~2 \\times 10^{-6} Msun/yr for a wind velocity of 10 km/sec, in close agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4--2.0 keV X-ray flux at ~100 days after explosion. SN ...

2001-01-01

110

The infrared-dominated jet of 3C401  

CERN Document Server

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

2005-01-01

111

TELEMETRY LINK FOR Howard A. Baldwin and Robert W. - NASA ...  

Science.gov (United States)

Howard A. Baldwin and Robert W. Freyman. (NASA-CR-138152) TELEMERY LINK FOR AN. 574-2179 9 ..... Baldwin, H.A., "Long Range Radio Tracking of ...

112

Scintillation Velocity of PSR B0329+54  

Science.gov (United States)

We monitored PSR B0329+54 for one year using the Nanshan 25-m radio telescope, the scintillation velocity V ISS shows evidence of systematic variation with the day of the year. States of interstellar medium (ISM) are discussed.

2011-07-01

113

Radio frequency noise from an MLC: a feasibility study of the use of an MLC for linac-MR systems  

UK PubMed Central (United Kingdom)

Currently several groups are actively researching the integration of a megavoltage teletherapy unit with magnetic resonance (MR) imaging for real-time image-guided radiotherapy. The use of a...Full Text Available

2010-02-21

114

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

International Nuclear Information System (INIS)

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

2010-10-10

115

No short-term effects of digital mobile radio telephone on the awake human electroencephalogram  

Energy Technology Data Exchange (ETDEWEB)

A recent study reported the results of an exploratory study of alterations of the quantitative sleep profile due to the effects of a digital mobile radio telephone. Rapid eye movement (REM) was suppressed, and the spectral power density in the 8--13 Hz frequency range during REM sleep was altered. The aim of the present study was to illuminate the influence of digital mobile radio telephone on the awake electroencephalogram (EEG) of healthy subjects. For this purpose, the authors investigated 34 male subjects in a single-blind cross-over design experiment by measuring spontaneous EEGs under closed-eyes condition from scalp positions C{sub 3} and C{sub 4} and comparing the effects of an active and an inactive digital mobile radio telephone (GSM) system. During exposure of nearly 3.5 min to the 900 MHz electromagnetic field pulsed at a frequency of 217 Hz and with a pulse width of 580 {micro}s, the authors could not detect ...

1997-05-01

116

National Institutes of Health (NIH) Health Matters Podcasts  

Science.gov (United States)

60 http://www.nih.gov/news/radio/healthmatters/index.htm 60-second Health Matters spots-one unique health report for each weekday of the month. en-us 2010 Mon, 01 Feb 2010 12:00:00...

2011-08-26

117

Limits on the Diffuse Radio and Hard X-ray Emission of Abell 2199  

CERN Document Server

The Westerbork Northern Sky Survey (WENSS) and the NRAO/VLA Sky Survey (NVSS) were used to determine an upper limit to the diffuse radio flux from the nearby cluster Abell 2199. For the entire cluster, this limit is <3.25 Jy at 327 MHz from WENSS; for the inner 15' radius, the limit is <168 mJy at 1.4 GHz. These limits are used to constrain the cluster magnetic field by requiring that the radio flux be consistent with the hard X-ray (HXR) flux observed by BeppoSAX, assuming that the observed HXR excess is due to inverse Compton (IC) scattering of cosmic microwave background photons by relativistic electrons in the intracluster gas. We find that the magnetic field must be very weak (<0.073 uG) in order to avoid producing an observable radio halo. We also consider the possibility that the HXR excess is due to nonthermal bremsstrahlung (NTB) by a population of suprathermal electrons which are being accelerated to ...

1999-01-01

118

Effect of #gamma#-irradiation on relaxation properties of sealants on organosilicon rubber base  

International Nuclear Information System (INIS)

The dielectrical properties of organosilicon sealants have been studied in the wide range of temperatures in the low and radio frequencies range. The effect of thermal treatment and #gamma#-irradiation on these properties is discussed.

119

Chandra Observations of Nuclear X-ray Emission from a Sample of Radio Sources  

CERN Document Server

We present the X-ray properties of a sample of 17 radio sources observed with the Chandra X-ray Observatory as part of a project aimed at studying the X-ray emission from their radio jets. In this paper, we concentrate on the X-ray properties of the unresolved cores. The sample includes 16 quasars (11 core-dominated and 5 lobe-dominated) in the redshift range z=0.30--1.96, and one low-power radio-galaxy at z=0.064. No diffuse X-ray emission is present around the cores of the quasars, except for the nearby low-power galaxy that has diffuse emission on a scale and with a luminosity consistent with other FRIs. No high-amplitude, short-term variability is detected within the relatively short Chandra exposures. However, 1510-089 shows low-amplitude flux changes with a timescale of $\\sim$25 minutes. The X-ray spectra of the quasar cores are generally well described by a single power law model with Galactic absorption. However, ...

2003-01-01

120

A search for electron cyclotron maser emission from compact binaries  

CERN Document Server

Unipolar induction (UI) is a fundamental physical process, which occurs when a conducting body transverses a magnetic field. It has been suggested that UI is operating in RX J0806+15 and RX J1914+24, which are believed to be ultra-compact binaries with orbital periods of 5.4 min and 9.6 min respectively. The UI model predicts that those two sources may be electron cyclotron maser sources at radio wavelengths. Other systems in which UI has been predicted to occur are short period extra-solar terrestrial planets with conducting cores. If UI is present, circularly polarised radio emission is predicted to be emitted. We have searched for this predicted radio emission from short period binaries using the VLA and ATCA. In one epoch we find evidence for a radio source, coincident in position with the optical position of RX J0806+15. Although we cannot completely exclude that this is a chance alignment between ...

2007-01-01

121

Winter study of power plant effects  

Energy Technology Data Exchange (ETDEWEB)

As a part of DOE's Meteorological Effects of Thermal Energy Releases (METER) program a field study was undertaken at the Bowen Electric Generating Plant (Plant Bowen) in December 1979. The study was a joint endeavor of Battelle Pacific Northwest Laboratories (PNL), Pennsylvania State University (PSU), and Oak Ridge National Laboratory (ORNL) with the main objective of determining the effects of the plant's smokestack effluents on aerosol characteristics and precipitation chemistry. Other objectives included studies of cooling tower temperature and humidity (T/h) plumes and drift drop concentrations. Conducted over a period of three weeks, the study involved an instrumented aircraft, pilot balloons, a tethered balloon system, a dense network of wetfall chemistry collectors and numerous ground- and tower-based meteorological instruments. Rainfall samples collected during the precipitation event of December 13, 1979, revealed some evidence of plume washout. The tethered ...

1980-10-01

122

The Third US Naval Observatory CCD Astrograph Catalog (UCAC3)  

CERN Document Server

The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3 was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8 to 16 magnitudes. Current epoch positions are obtained from the observations with the 20 cm aperture USNO Astrograph's "red lens", equipped with a 4k by 4k CCD. Proper motions are derived by combining these observations with over 140 ground- and space-based catalogs, including Hipparcos/Tycho and the AC2000.2, as well as unpublished measures of over 5000 plates from other astrographs. For most of the faint stars in the Southern Hemisphere the Yale/San Juan first epoch plates from the SPM program (YSJ1) form the basis for proper motions. These data are supplemented by all-sky Schmidt plate survey astrometry and photometry obtained from the SuperCOSMOS project, as well as 2MASS near-IR ...

2010-01-01

123

The Hard X-ray Spectral Evolution in XRBs, AGNs and ULXs  

CERN Document Server

We explore the relationship between the hard X-ray photon index $\\Gamma$ and the Eddington ratio (\\xi=L_{X}(0.5-25 keV)/L_{Edd}) in six XRBs. We find that different XRBs follow different anti-correlations between $\\Gamma$ and $\\xi$ when $\\xi$ is less than a critical value, while they follow the same positive correlation when $\\xi$ is larger than the critical value. This anti-correlation and positive correlation are also found in LLAGNs and QSOs respectively, and the anti-correlation and positive correlation of different XRBs roughly converge to the same point ($\\log \\xi=-2.1, \\Gamma=1.5$), which may correspond to the accretion mode transition, since that the anti-correlation and positive correlation are consistent with the prediction of ADAFs and standard disk/corona system respectively. The traditional low/hard state are divided into two parts by the cross point $\\log \\xi\\sim-2.1$, i.e., faint-hard state in the anti-correlation part and bright-hard ...

2008-01-01

124

Rotational velocities and central velocity dispersions for a sample of S0 galaxies  

International Nuclear Information System (INIS)

Central velocity dispersions and rotation curves to radii of approx.5 kpc have been measured for 32 galaxies, mostly field S0's. Our rotation curves confirm the result of Kormendy and Illingworth that the bulges of S0 galaxies are in rapid rotation, with enough rotational kinetic energy to account for their flattenings. The V/sigma-ellipticity relation we find for S0 bulges is compared with similar data for elliptical galaxies from Davies et al. We conclude that (1) faint SO bluges and elliptical galaxies (M/sub B/ fainter than -20.5) are both consistent with oblate rotators with isotropic velocity dispersions (although in our sample, S0 bluges are flatter, on the average, than ellipticals) and (2) bright S0 bulges, -22.0

125

Optical Modelling of the HFI Instrument on Board the Planck Surveyor  

Science.gov (United States)

The PLANCK SURVEYOR is a European Space Agency satellite mission to image the very faint anisotropies in the temperature of the Cosmic Microwave Background (CMB) radiation. Maynooth is actively participating in an international collaboration of scientists involved with the optical design of the High Frequency Instrument (HFI). This paper outlines research which has been undertaken in Maynooth concerned with numerical modelling of the optical characteristics of the multi-frequency array of detectors making up the HFI instrument. In the study the commercial software package ZEMAX was used to model the coupling of the focal plane HFI detectors to the PLANCK telescope. This package is particularly useful in the optical design of PLANCK because of the powerful optimisation features of the software. It is thus possible to readily determine the optimum positioning of the detectors in the focal plane of the telescope. Although the package is based on a numerical ray ...

1999-07-01

126

Moderately heavy, heavy-fermion compound YbPd_2Si_2 at low temperatures  

International Nuclear Information System (INIS)

The available experimental data on the specific heat, magnetic susceptibility, magnetization, valence, NMR Knight shift and relaxation rate, and the quadrupolar moment of YbPd_2Si_2 are examined within the framework of the single-ion Anderson model. Such an analysis has previously given excellent agreement between theory and experiment for numerous other light heavy-fermion compounds, where crystalline fields do not play a dominant role. For YbPd_2Si_2, substantial crystalline-field splittings make difficult a quantitative comparison with existing exact solutions of the Anderson model. Inconsistencies with the interpretation that a nearly degenerate ground quadruplet determines the low-temperature thermodynamics are pointed out. It is concluded that at least three of the four Kramers doublets participate in the low-T properties. These three doublets should have a splitting of the order of the Kondo temperature, i.e., about 100 K. A simple resonant-level model parametrizing the NMR ...

127

Moderately heavy, heavy-fermion compound YbPd sub 2 Si sub 2 at low temperatures  

Energy Technology Data Exchange (ETDEWEB)

The available experimental data on the specific heat, magnetic susceptibility, magnetization, valence, NMR Knight shift and relaxation rate, and the quadrupolar moment of YbPd{sub 2}Si{sub 2} are examined within the framework of the single-ion Anderson model. Such an analysis has previously given excellent agreement between theory and experiment for numerous other light heavy-fermion compounds, where crystalline fields do not play a dominant role. For YbPd{sub 2}Si{sub 2}, substantial crystalline-field splittings make difficult a quantitative comparison with existing exact solutions of the Anderson model. Inconsistencies with the interpretation that a nearly degenerate ground quadruplet determines the low-temperature thermodynamics are pointed out. It is concluded that at least three of the four Kramers doublets participate in the low-{ital T} properties. These three doublets should have a splitting of the order of the Kondo temperature, i.e., about 100 K. A simple resonant-level model ...

1992-07-01

128

Detection of H2 Emission from Mira B in UV Spectra from the Hubble Space Telescope  

CERN Document Server

We present ultraviolet spectra of Mira's companion star from the Space Telescope Imaging Spectrograph (STIS) instrument on board the Hubble Space Telescope (HST). The companion is generally assumed to be a white dwarf surrounded by an accretion disk fed by Mira's wind, which dominates the UV emission from the system. The STIS UV spectrum is dominated by numerous, narrow H2 lines fluoresced by H I Ly-alpha, which were not detected in any of the numerous observations of Mira B by the International Ultraviolet Explorer (IUE). The high temperature lines detected by IUE (e.g., C IV 1550) still exist in the STIS spectrum but with dramatically lower fluxes. The continuum fluxes in the STIS spectra are also much lower, being more than an order of magnitude lower than ever observed by IUE, and also an order of magnitude lower than fluxes observed in more recent HST Faint Object Camera objective prism spectra from 1995. Thus, the accretion rate onto Mira B was apparently ...

2001-01-01

129

Broadband Imaging Segregation of z ~ 3 Ly-alpha Emitting and Ly-alpha Absorbing Galaxies  

CERN Document Server

The spectral properties of Lyman break galaxies (LBGs) offer a means to isolate pure samples displaying either dominant Ly-alpha in absorption or Ly-alpha in emission using broadband information alone. We present criteria developed using a large z ~ 3 LBG spectroscopic sample from the literature that enables large numbers of each spectral type to be gathered in photometric data, providing good statistics for multiple applications. In addition, we find that the truncated faint, blue-end tail of z ~ 3 LBG population overlaps and leads directly into an expected Ly-alpha emitter (LAE) population. As a result, we present simple criteria to cleanly select large numbers of z ~ 3 LAEs in deep broadband surveys. We present the spectroscopic results of 32 r' <~ 25.5 LBGs and r' <~ 27.0 LAEs at z ~ 3 pre-selected in the Canada-France-Hawaii Telescope Legacy Survey that confirm these criteria.

2009-01-01

130

Electromagnetic characterization of superconducting radio-frequency cavities for gw detection  

International Nuclear Information System (INIS)

The electromagnetic properties of a prototype gravitational wave detector, based on two coupled superconducting microwave cavities, were tested. The radio-frequency (rf) detection system was carefully analysed. With the use of piezoelectric crystals small harmonic displacements of the cavity walls were induced and the parametric conversion of the electromagnetic field inside the cavities explored. Experimental results of bandwidth and sensitivity of the parametric converter versus stored energy and voltage applied to the piezoelectric crystal are reported. A rf control loop, developed to stabilize phase changes on signal paths, gave a 125 dBc rejection of the drive mode on a time scale of 1 h.

2004-03-07

131

5 GHz 200 Mbit/s radio over polymer fibre link with envelope detection at 650 nm wavelength  

DEFF Research Database (Denmark)

All-optical envelope detection of a 5 GHz 200 Mbit/s modulated radio frequency signal is achieved using a 650 nm resonant cavity light emitting diode. Error-free transmission is achieved over a 50 m-long link of 1 mm diameter graded index polymer optical fibre (POF). The presented system has potential applications in low cost and low complexity short range wireless and wireline POF-based transmission links.

2008-01-01

132

All aboard: Terra Nova 'not for the faint hearted'  

Energy Technology Data Exchange (ETDEWEB)

The state of exploration in the Terra Nova field offshore Newfoundland, and the progress in constructing the floating production, storage and offloading (FPSO) at Bull Arm, the assembly site west of St. John's for the Terra Nova vessel, are described. Comparisons are made between the excitement created by the first production well at Leduc in Western Canada in 1947, and the offshore developments currently underway and accelerating offshore Newfoundland. It is estimated that exploration and development offshore had barely touched the surface, with only 160 wells of all types drilled to date, of which 48 exploration wells have uncovered 1.7 billion barrels of oil. The area is practically unexplored; the source rock is there, and the current estimate is that there are a number of basins in the offshore area that are several times the size of the Jeanne d'Arc Basin, where the Hibernia field is currently producing about 135,000 barrels of oil per day. The total estimated ...

2001-08-06

133

Radiofrequency electromagnetic fields in the Cookridge area of Leeds  

Energy Technology Data Exchange (ETDEWEB)

On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In ...

2002-07-01

134

Field investigation of radio network usage at the dismounted infantry section level  

Science.gov (United States)

The Soldier Information Requirements Technology Demonstration (SIREQ TD) project is an experimentation program to identify technologies that significantly enhance the performance of our future soldiers. One of the study series involved a 2 x 2 factorial comparison of the benefits of digital maps over paper maps, and the use of radios vs. no radios. Thirty-two Canadian regular force infantry soldiers performed force-on-force tactical assault missions in wooded terrain, with each soldier participating in all four test conditions. The radios were configured to operate in 4 subnets: 1 channel for each of the 2 Assault Groups (4 soldiers on a channel); a Section Commander/2IC channel; and an all-users channel. Note that in the no-radio conditions soldiers still operated the press-to-talk switch to allow recording of communications, but the speaker volume was set to zero. All communications were date/time ...

2006-06-01

135

GAS EVOLUTION FROM INSULATING MATERIALS FOR SUPERCONDUCTING COIL OF ITER BY GAMMA RAY IRRADIATION AT LIQUID NITROGEN TEMPERATURE  

International Nuclear Information System (INIS)

A laminated material composed of glass cloth/polyimide film/epoxy resin will be used as an insulating material for superconducting coil of International Thermonuclear Experimental Reactor (ITER). In order to keep safe and stable operation of the superconducting coil system, it is indispensable to evaluate radiation resistance of the material, because the material is exposed to severe environments such as high radiation field and low temperature of 4 K. Especially, it is important to estimate the amount of gases evolved from the insulating material by irradiation, because the gases affect on the purifying system of liquid helium in the superconducting coil system. In this work, the gas evolution from the laminated material by gamma ray irradiation at liquid nitrogen temperature (77 K) was investigated, and the difference of gas evolution behavior due to difference of composition in the epoxy resin was discussed. It was found that the main gases ...

2008-03-03

136

Dynamic behaviors of sulfur evolved in the gas phase from pyrolysis of six Chinese coals  

Energy Technology Data Exchange (ETDEWEB)

Dynamic behaviors of gaseous sulfur-containing compounds evolved from pyrolysis of six Chinese coals were studied in the temperature range of up to 800{sup o}C under N{sub 2} and H{sub 2}. The released amount of total sulfur-containing gases was traced by an online flame photometric detector (FPD). Simultaneously, the changes of different sulfur forms, including H{sub 2}S, SO{sub 2}, COS and CS{sub 2}, also were investigated using an online mass spectrometer (MS). FPD results show that the effect of H{sub 2} on gaseous sulfur evolved is complex, which promoted certain peak and suppresses other peaks. Based on the data from MS, it is suggested that a series of competitive reactions between active sulfur and other active matters during pyrolysis may impact on the sulfur form in gas phase. Interactions between active sulfur-containing intermediates and the coal matrix are attributed to be the main factor determining the dynamic behavior.

2006-07-01

137

Technological evolution and interdependence in China's emerging biofuel industry  

British Library Electronic Table of Contents (United Kingdom)

This study uses the European Patent Office worldwide patent database and applies two-stage interactive data collection methods to reveal the evolving technological interdependence for China's emerging biofuel industry. Three findings are excerpted from our empirical results. First, due to dominant patterns of business ownership, China's biofuel technology is seen as largely based on the evolutionary strength of the foodstuff and chemical fields. Second, China's biofuel technology development has evolved in the mode of 'forward engineering', led by Chinese universities rather than initiated by the public research institutes as in the experience of other East Asian latecomers. Third, our patent map and technology trajectory analyses illustrate that China's biofuel technology tends to be appl...

2011-01-01

138

Quantitative model of vapor dominated geothermal reservoirs as heat pipes in fractured porous rock  

Science.gov (United States)

We present a numerical model of vapor-dominated reservoirs which is based on the well-known conceptual model of White, Muffler, and Truesdell. Computer simulations show that upon heat recharge at the base, a single phase liquid-dominated geothermal reservoir in fractured rock with low matrix permeability will evolve into a two-phase reservoir with B.P.D. (boiling point-for-depth) pressure and temperature profiles. A rather limited discharge event through cracks in the caprock, involving loss of only a few percent of fluids in place, is sufficient to set the system off to evolve a vapor-dominated state. The attributes of this state are discussed, and some features requiring further clarification are identified. 26 refs., 5 figs.

1985-03-01

139

Design principles for CANDU control centres in response to evolving utility business needs  

Energy Technology Data Exchange (ETDEWEB)

Nuclear generation operators are facing a challenging business environment at the beginning of the new millennium. Evolving changes in business context, competitive commercial pressures, and changes in technology have dictated recurring evaluation of operational practices and the adequacy of supporting tools, and the pursuit of opportunities for operational improvement. A key area of utility operations that has been impacted by these changes is the nuclear plant control centre. Changes to workspace layout, equipment provisions, staffing, and work organization are examples of some of the adjustments being introduced to improve operational and safety effectiveness. This paper discusses some of the key factors influencing these changes and identifies additional design principles for CANDU control centres that will enable new control centre designs and retrofits of existing control centres to remain relevant and responsive to utility needs. (author)

2002-07-01

140

Polarised foreground removal at low radio frequencies using rotation measure synthesis: Uncovering the signature of hydrogen reionisation  

CERN Document Server

Measurement of redshifted 21-cm emission from neutral hydrogen promises to be the most effective method for studying the reionisation history of hydrogen and, indirectly, the first galaxies. These studies will be limited not by raw sensitivity to the signal, but rather, by bright foreground radiation from Galactic and extragalactic radio sources and the Galactic continuum. In addition, leakage due to gain errors and non-ideal feeds conspire to further contaminate low-frequency radio obsevations. This leakage leads to a portion of the complex linear polarisation signal finding its way into Stokes I, and inhibits the detection of the non-polarised cosmological signal from the epoch of reionisation. In this work, we show that rotation measure synthesis can be used to recover the signature of cosmic hydrogen reionisation in the presence of contamination by polarised foregrounds. To achieve this, we apply the rotation measure synthesis technique to ...

2010-01-01

141

Nigerian Urban Women's Use of Information Media: The Challenges for Women in Leadership  

Science.gov (United States)

The study surveyed urban women's use of information media and drew attention to the implications for women in leadership positions and non-formal education. A questionnaire containing structured and unstructured items was administered to 300 women resident at Nsukka urban town Enugu State, Nigeria. One hundred and twenty-five usable copies were used for the data analysis. The findings show that oral media are the most popular among women irrespective of level of education and type of occupation. The level of education influenced the use of radio and television. Popular radio and television programmes among women include newscasts, socio-cultural programmes, music and drama. Problems hindering women's use of radio and television include time constraint, poor reception, poor condition of available sets and lack of money for repairs among others. Based on these findings the implication for the achievement of the Universal ...

2008-10-01

142

High Spatial Resolution Optical and Radio Imagery of the Circumbinary Environment  

CERN Document Server

In this review, I concentrate on describing observations of spatially resolved emission in symbiotic stars at sub-arcsecond scales. In some of the closer objects, the highest resolutions discussed here correspond to linear dimensions similar to the supposed binary separation. A total of 17 stars well accepted as symbiotics are now observed to show sub-arcsecond structure, almost twice the number at the time of the last review in 1987. Furthermore, we now have access to HST imagery to add to radio interferometry. From such observations we can derive fundamental parameters of the central systems, investigate the variation of physical parameters across the resolved nebulae and probe the physical mechanisms of mass loss and interactions between ejecta and the circumstellar medium. Suggestions for future work are made and the potential of new facilities in both the radio and optical domains is described. This review complements that by Corradi (this ...

2004-01-01

143

Development of enhanced radioprotectors - Biochemical and molecular genetical approaches on the radioprotective mechanism of natural products  

Energy Technology Data Exchange (ETDEWEB)

To identify radio-protective agent candidate among medicinal plants and to elucidate the mechanism of action of the candidate material by using modern biochemical and molecular biological methods, we screened radio-protective activity among 48 medicinal plants. Seven samples showed above 20% protective activities against oxidative cell damage: Euryale ferox, Glycyrrhiza uralensis, Salvia miltiorrhiza, Eucomia ulmoides, Paeonia suffruticosa, Spirodela polyrrhiza, and Nelumbo nucifera. We also screened for oxidative stress sensitizing activity among other 51 medicinal plants. Among those samples, 11 samples showed good sensitizing effect; Melia azedarach, Agastache rugosa, Catalpa ovata, Prunus persica, Sinomenium acutum, Pulsatilla koreana, Oldenlandia diffusa, Anthriscus sylvestris, Schizandra chinensis, Gleditsia sinensis, and Cridium officinale. We also reported the radio-protective effect of DTT. The treatment of DTT ...

2000-04-01

144

An alternative explanation of the COBE data  

Energy Technology Data Exchange (ETDEWEB)

The COBE data on cosmic background radiation (CBR) isotropy and spectrum are generally considered to be explicable only in the context of the Big Bang theory and to be confirmation of that theory. However, this data can also be explained by an alternative, non-Big Bang model which hypothesizes an intergalactic radio-absorbing and scattering medium. Dense, force-free magnetic filaments generated by quasars, active galactic nuclei and Herbig-Haro objects can remain stable in the intergalactic medium for many Gy. They will be opaque to radiation with wavelengths longer than 100--400 microns, and essentially transparent to shorter wavelengths. They are thus capable of thermalizing and isotropizing the cosmic background radiation, and of accounting for the observed decrease of radio luminosity of galaxies within increasing distance from earth. A simple, inhomogeneous model of such an absorbing medium can reproduce both the isotropy and spectrum of ...

1994-12-31

145

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

CERN Document Server

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

2009-01-01

146

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

CERN Document Server

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

2003-01-01

147

The role of Multidetector CT in the evaluation of the left atrium and pulmonary veins anatomy before and after radio-frequency catheter ablation for atrial fibrillation. Preliminary results and work in progress.Technical note  

International Nuclear Information System (INIS)

Radio-frequency catheter ablation (RFCA) of the distal pulmonary veins is increasingly being used to treat recurrent or refractory atrial fibrillation that doesn't respond to pharmacologic therapy or cardioversion. Successful RFCA of atrial al fibrillation depends on the pre-procedural understanding of the complex anatomy of the distal pulmonary veins and the left atrium. Aim of this parer is to describe the technical main features that characterise the multidetector helical computed tomography in the evaluation of this anatomic region before and after RFCA procedure. The 3D post-processing techniques useful for pre-RFCA planning are straightforward.

148

The radio jet in NGC 6251  

International Nuclear Information System (INIS)

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

149

The X-ray Halo of G21.5-0.9  

CERN Document Server

The emission of the plerion G21.5-0.9 appears more extended in X rays than in radio. This is an unexpected result because it would imply that short-lived X-ray electrons may reach distances even larger than radio electrons. Applying an empirical relationship between dust scattering optical depth and photoelectric column density, the measured column density leads to a large optical depth at 1 keV, of about 1. Therefore we investigate the hypothesis that the detected halo be an effect of dust scattering, re-analyzing an Cal/PV XMM-Newton observation of G21.5-0.9 and critically examining it in terms of a dust scattering model. We also present a spectral analysis of a prominent extended feature in the northern sector of the halo.

2003-01-01

150

TUNABLE FIBER FABRY-PEROT FILTER FOR OPTICAL CARRIER-SUPPRESSION AND SINGLE-SIDEBAND MODULATION IN RADIO OVER FIBER LINKS  

British Library Electronic Table of Contents (United Kingdom)

A novel method of simultaneous realization of optical carrier-suppression and single-sideband modulation using fiber Fabry-Perot tunable filter is presented. In order to enhance transmission performance of radio over fiber links, we use a fiber Fabry-Perot tunable filter to filter out one sideband as well as suppress the optical carrier power. The results demonstrate 20.5dB and 14.2dB improvement in the signal noise ratios when 18GHz and 10GHz microwave signals carrying 5Mbit/s quadrature-phase-shift-keyed (QPSK) format data is transmitted over 35 km single mode fiber, respectively.

2006-01-01

151

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

International Nuclear Information System (INIS)

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

2010-03-10

152

Solar-Geophysical Data Number 568, December 1991. Part 1 (prompt reports). Data for November, October 1991 and late data  

Energy Technology Data Exchange (ETDEWEB)

The contents include: Detailed index for 1991; Data for November 1991--Solar-terrestrial environment, IUWDS alert periods (advance and worldwide), Solar activity indices, Solar flares, Solar radio emission, Stanford mean solar magnetic field; Data for October 1991--Solar active regions, Sudden ionospheric disturbances, Solar radio spectral observations, Cosmic ray measurements by neutron monitor, Geomagnetic indices; Late data--Cosmic ray measurements by neutron monitor (Climax February and May 1990, Deep River May-August 1991), Geomagnetic indices (Sudden commencements/Solar flare effects January-May 1991); Errata--August 1991 Geomagnetic activity indices.

1991-12-01

153

Radio nuclear aggression. Psychological impact and management; L'agression radio-nucleaire. Impact psychologique et prise en charge  

Energy Technology Data Exchange (ETDEWEB)

Long before possible organic effects, exposure to ionizing radiations can provoke anxiety. In front of invisibility, the imagination quickly ignites. The terrorists have perfectly understood it. They are ready to use ionizing radiations as a weapon to remind traumatic images deeply rooted in people's memory. These images induce anxiety with all the clinical expressions connected to it. These symptoms require to be treated because of a possible anarchic development. For that purpose, plans have been elaborated to coordinate the different professional's actions. The coherence of medical management and communication aims to allow the most implicated people to find the way to face the events. When it is not possible, medico-psychological cells permit a specialized care. (author)

2006-08-15

154

Radio frequency plasma nitriding of aluminium at higher power levels  

International Nuclear Information System (INIS)

Nitriding of aluminium 2011 using a radio frequency plasma at higher power levels (500 and 700 W) and lower substrate temperature (500 deg. C) resulted in higher AlN/Al_2O_3 ratios than obtained at 100 W and 575 deg. C. AlN/Al_2O_3 ratios derived from X-ray photoelectron spectroscopic analysis (and corroborated by heavy ion elastic recoil time of flight spectrometry) for treatments preformed at 100 (575 deg. C), 500 (500 deg. C) and 700 W (500 deg. C) were 1.0, 1.5 and 3.3, respectively. Scanning electron microscopy revealed that plasma nitrided surfaces obtained at higher power levels exhibited much finer nodular morphology than obtained at 100 W.

2006-12-05

155

Quasi-stationary and transient patterns in jets  

Science.gov (United States)

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

2011-01-01

156

Passivation of uranium metal by radio-frequency plasma nitriding against gas phase (H{sub 2}, H{sub 2}O) corrosion  

Energy Technology Data Exchange (ETDEWEB)

Thin passive layers of uranium nitride were formed by nitriding pure metallic uranium in non-equilibrium, low pressure radio-frequency plasma of nitrogen. Plasma nitriding at low substrate temperature of 230 C-250 C was found to cause the formation of adherent layers of uranium sesquinitride ({alpha}-U{sub 2}N{sub 3}) which provide a considerable protection against hydrogen attack. The characteristics of these passivation layers were determined by X-ray diffraction and Auger electron spectroscopy. The incipient hydriding kinetics of the plasma-treated samples were compared with those of untreated and nitrogen-ion implantation ones, utilizing a hot-stage microscope that was monitored continuously with a TV camera and videotape. (orig.)

1996-07-01

157

An evaluation of the embedment of a Radio Frequency Integrated Circuit with a temperature detector in building envelopes for energy conservation  

British Library Electronic Table of Contents (United Kingdom)

Concrete is the primary material for building envelopes in some parts of the world, and its ability to store heat as well as its dynamic temperature changes will not only affect the deterioration rate of the exterior wall but will also greatly influence the energy efficiency of interior air conditioning. There are many methods for measuring the inner temperature of concrete, but they often have limitations, such as indirect estimation, cable installation requirements, high cost, or heterogeneity of the sample structure. In order to measure the internal temperature of concrete, this study integrated a Radio Frequency Integrated Circuit (RFIC) with a temperature sensor chip and embedded the device in concrete structures. A Smart Temperature Information Material (STIM) was thus developed. Thi...

2011-01-01

158

A MAC protocol for cognitive wireless sensor body area networking  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this paper, a Cognitive Radio Based Medium Access Control (CR-MAC) protocol for Wireless Sensor Body Area Networks (WSBAN) that utilizes cognitive radio transmission is proposed. In this proposal, the sensor nodes are classified into nodes of life-critical health information and nodes of non-critical health information. The CR-MAC protocol prioritizes the critical packets access to the transmission medium by transmitting them with higher power while transmitting lower priority packets using lower transmission power. At the receiver, a higher priority packet experiences collision only when there are more than one critical packet transmission at the same transmission slot while non critical packets experience collision when there are more than one transmission at the same transmi...

2010-01-01

159

Warm-Intermediate inflationary universe model in braneworld cosmologies  

CERN Document Server

Warm-intermediate inflationary universe models in the context of braneworld cosmologies, are studied. This study is done in the weak and strong dissipative regimes. We find that, the scalar potentials and dissipation coefficients in terms of the scalar field, evolves as type-power-law and powers of logarithms, respectively. General conditions required for these models to be realizable are derived and discussed. We also study the scalar and tensor perturbations for each regime. We use recent astronomical observations to constraint the parameters appearing in the braneworld models.

2011-01-01

160

The issues in electronics hardening  

International Nuclear Information System (INIS)

This paper addresses the background and the continuously evolving topics of hardening and electronic components. Typical radiation environments from 1960 are described. Examples of a civilian satellite and of future particle physics colliders help illustrate hardening problems. Effects in components, limits of shielding, and three methods of providing components are described. The authors conclude by focusing on both future trends of radiation environments and anticipated progress in electronics. (authors). 10 refs., 9 figs., 4 tabs.

161

The Protein Kinase SnRK2.6 Mediates the Regulation of Sucrose Metabolism and Plant Growth in Arabidopsis[W][OA]  

UK PubMed Central (United Kingdom)

In higher plants, three subfamilies of sucrose nonfermenting-1 (Snf1)-related protein kinases have evolved. While the Snf1-related protein kinase 1 (SnRK1) subfamily has been shown to share pivotal...Full Text Available

2010-05-01

162

Text Mining Classification, Clustering, and Applications  

CERN Document Server

An extension of data mining, text mining involves the extraction of information and knowledge from unstructured text. This constantly evolving field is increasingly used by major corporations, such as Google, Yahoo, and Microsoft. Featuring contributions from leading researchers in the field, this book provides a detailed overview of text mining theory, applications, and visualization. The theory section discusses text mining, information retrieval, latent semantic analysis, pagerank, latent Dirichlet allocation, and probabilistic relational models. In the section on text mining applications,

2009-01-01

163

Plan-view transmission electron microscopy of crack tips in bulk materials  

Energy Technology Data Exchange (ETDEWEB)

A focused ion beam (FIB) system has been applied to prepare a thin foil specimen of Si, MgO and alumina which contained cracks in the plan of foil. It was possible to observe a much larger area at and near a crack tip than has been hitherto possible. FIB was also applied to observation of microstructure near a crack tip evolved during severe rolling contact fatigue in a steel.

1996-12-01

164

Photovoltaics: Program overview, fiscal year 1992  

Energy Technology Data Exchange (ETDEWEB)

The US DOE`s Photovoltaics program has helped photovoltaic technologies evolve from materials and concepts in the laboratories to competitive products rolling off automated assembly lines. This document is divided into the following sections: 1992 PV program accomplishments, expanding markets for photovoltaic systems, developing today`s systems with utilities and industry, working with industry to advance the technology, cooperative research to improve materials and devices, selected achievements in cooperative R and D, and PV program services. Figs, tabs.

1993-03-01

165

Experimental research of spontaneous evolution from ultracold rydberg atoms to plasma  

International Nuclear Information System (INIS)

The spontaneous evolution from ultracold Rydberg atoms to plasma is investigated in a caesium MOT by using the method of field ionization. The plasma transferred from atoms in different Rydberg states (n=22-32) are obtained experimentally. Dependence of the threshold time of evolving to plasma and the threshold number of initial Rydberg atoms on the principal quantum number of initial Rydberg states is studied. The experimental results are in agreement with hot-cold Rydberg-Rydberg atom collision ionization theory. (authors)

2008-04-01

166

Dynamical evolution and molecular abundances of interstellar clouds  

International Nuclear Information System (INIS)

Dynamical models are presented that start with interstellar gas in an initial diffuse state and consider their gravitational collapse and the formation of dense cores. Frozen-in tangled magnetic fields are included to mimic forces that might oppose gravitational contraction and whose effectiveness may increase with increasing core densities. Results suggest the possibility that dense cloud cores may be dynamically evolving ephemeral objects, such that their lifespan at a given core density decreases as that density increases. 66 refs.

167

Delta Scuti stars and stellar evolution  

International Nuclear Information System (INIS)

Recent developments in the knowledge of Delta Scuti stars in relation to stellar evolution are reviewed. The stability of periods and amplitudes is examined, and a working hypothesis suggested. Furthermore, the systematics of the observed long-term period changes are compared with the computed evolutionary tracks, suggesting a severe disagreement for the evolved stars if the period changes are caused by radius changes resulting from stellar evolution. 30 refs.

1990-05-28

168

Cosmological BCS condensate as dark energy  

CERN Document Server

We argue that the occurrence of late-time acceleration can conveniently be described by first-order general relativity covariantly coupled to fermions. Dark energy arises as a gravitationally driven BCS condensate of fermions which forms in the early universe. At late times, the gap and chemical potential evolve to have an equation of state with effective negative pressure, thus naturally leading to acceleration.

2009-01-01

169

Cosmic no-hair in Brans-Dicke theory  

International Nuclear Information System (INIS)

In this short note we report our finding that within the context of alternative version of the Brans-Dicke theory (for #omega# #>=# -3/2, where #omega# is the Brans-Dicke parameter) the anisotropic Bianchi type cosmological models evolve towards the de Sitter isotropic universe. In short it is shown that during inflation there is no difference between the Brans-Dicke theory and General Relativity. Our result can thus be viewed as a generalization of the Wald's theorem for General Relativity. (author). 5 refs.

2009-04-07

170

The Performance Evaluation of a Hot Water Layer using a Numerical Simulation  

International Nuclear Information System (INIS)

Most of all research reactors are immerged in the deep water pool to be a ultimate heat sink. At the neighbor of the reactor, some radio-active matters, such as Na-24, Ar-41, Mg-27, Al-28 and etc, may be generated by the neutron irradiation. Those radio-active isotopes may rise up to the pool water surface through the natural convection flow, which can make the radioactivity in the reactor hall rise high enough to concern about the health of people working in the reactor hall. When the irradiation test facilities are loaded or unloaded during a normal operation, the highly radio-activated primary coolant may flow out through the irradiation test holes on the top of the reactor. This also may be a main hazard source to make the working environment of the reactor hall bad. Making a hot water layer 1.5 ? 2.0 m thick at the top of reactor pool would be a good measure to resolve that problem. The hot water layer is formed by a ...

2009-05-01

171

Telephone communications on a face with two steep machine tracks - tests with the mobile X-phone  

Energy Technology Data Exchange (ETDEWEB)

The author gives an account of tests with the X-phone system. The aim of the tests was to establish the reliability and behaviour of the apparatus mounted on a winning machine and to investigate the possibility of setting up a radio link, without laying an extra wire, between the foot of the tubbing-lined roadway and the winning machine on a steep face. The author describes the face and the test conditions and presents details of the satisfactory test results.

1981-11-01

172

Spin evolution in wind-fed X-ray binaries  

International Nuclear Information System (INIS)

Global angular momentum balance suggests that the neutron stars in Be/X-ray binaries are not spinning in equilibrium. This requires an X-ray lifetime ''approx <'' 10"5 yr, and suggests that there are many 'dead' Be/X-ray binaries in the Galaxy. Some of these may be turned up as millisecond radio pulsars with Be star companions. (author).

173

Solar effects on communications  

International Nuclear Information System (INIS)

This paper focuses on potential effects of solar phenomena on communication systems used by the electric utility industry. It begins with a discussion of solar phenomena fundamentals and discussion of the interaction between solar emissions and the earth's ionosphere and magnetosphere. It continues with a discussion of the resulting impacts on communication systems including radio, satellite, wireline, fiber optic, and powerline systems and concludes with a discussion of mitigation techniques and a call for observers to report suspected solar impact experiencexperiences.

174

Scintigraphic imaging of dementia: Technical acquisition  

International Nuclear Information System (INIS)

Scintigraphic imaging of dementia relies today essentially on the study of brain Single Photo Emission Computed Tomography (SPECT) perfusion, after intravenous injection of 99mTc radio-pharmaceutic. This paper is based on the guidelines published in October 2001 by the European Association of Nuclear Medicine (http://eanm.org/). (author)

2007-06-01

175

Report on the special program 78 satellite geodesy of the technical university of Munich  

Energy Technology Data Exchange (ETDEWEB)

Various topics include: (1) direction finding, (2) range finding, (3) Doppler measurements, (4) construction of a receiver for radio interferometry, (5) mobile laser range finding system, (6) figure-and field parameter determination/geopotential, (7) dynamics of the Earth-Moon system, and (8) kinematics of geodetic point fields.

1981-01-01

176

RF and microwave energy hots up  

Energy Technology Data Exchange (ETDEWEB)

The advantages of radiofrequency and microwaves, such as volumetric heating, rapid and selective heating, compactness of equipment and ease of operation, offer sound economic alternative heating techniques. This article discusses dielectric loss, its quantification, and how it is put to effective use, including the use of applicators. Brief recommendations are presented for whether to select radio frequency or microwaves for a particular application. Uses of radiofrequency and microwaves in the industrial, domestic and medical sectors are described.

1988-05-12

177

NAI: Year 4 Annual Report - NASA Astrobiology Institute  

Science.gov (United States)

His talk was based on the suggestion that life on Earh has been a long but accelerating ..... a New Class of Submarine Hydrothermal System"; April 29, 2002 , ..... of media personnel, including radio, television, newspapers, and magazines. ...... "The Birth of Stars and Planets" (Denver Museum of Nature and Science ...

178

Microwaves action applied to chemical reactions and processes; L`azione delle microonde nelle reazioni e nei processi chimici  

Energy Technology Data Exchange (ETDEWEB)

Microwaves improve the rate of many chemical reactions either interacting with the solvent, when the reaction is carried out in solution, or with the surface of a solid substrate where a suitable reagent is dispersed (dry chemistry). A few examples of chemical reactions positively affected by microwaves are described: particularly interesting are those concerning polymers and radio-pharmaceuticals.

1997-03-01

179

Microwaves - the hidden danger. Mikrowellen - die verheimlichte Gefahr  

Energy Technology Data Exchange (ETDEWEB)

Today, highly frequent radio waves are regarded as undangerous to man. Diseases seen at radar-technicians during the 2nd World War, however, indicated that microwaves applied in radar systems were hazardous to health. The Russian work medicine has been knowing microwave-caused hazards in industry since the beginning of the thirties. Therefore in some East-European countries there are terms of protection and severe norms of safety for the staying of persons in the radiation sphere of microwaves.

1987-01-01

180

Hyperfine interactions in HCOOD and DCOOH molecules  

Energy Technology Data Exchange (ETDEWEB)

The method of double microwave--radio-frequency resonance has been used to obtain spectra of the 2/sub 11/reverse arrow2/sub 12/ and 3/sub 21/reverse arrow3/sub 22/ transitions in HCOOD, DCOOH, and HCOOH molecules. The constants of the quadrupole bond of the deuterons have been determined, magnetic interactions being taken into acocunt. A comparison with results of previous studies is given.

1986-05-01

181

Heat Shock Protein 27-Targeted Heptapeptide of the PKC? Catalytic V5 Region Sensitizes Tumors With Radio- and Chemoresistance  

International Nuclear Information System (INIS)

Purpose: Previous data suggest that the PKC? catalytic V5 (PKC?-V5) heptapeptide (HEPT) (FEQFLDI) binds HSP27 and blocks HSP27-mediated radio- or chemoresistance. Here we investigated further the in vivo function of the PKC?-V5 HEPT. Methods and Materials: Labeling of HEPT with Cy5.5 or fluorescein isothiocyanate was performed to evaluate in vitro or in vivo distribution of HEPT. A clonogenic survival assay, flow cytometry, and Western blotting of cleaved caspase-3 were performed to determine in vitro sensitization effects of HEPT plus ionizing radiation (IR) versus IR alone or those of HEPT plus cisplatin(Cis) versus Cis alone. A nude mouse xenografting system was also applied to detect in vivo sensitizing effects of HEPT. Results: HEPT efficiently bound to HSP27 and showed sensitization after combined treatment with IR versus treatment with Cis alone in NCI-H1299 lung carcinoma cells, with higher HSP27 expression, which was similar to that of combined treatment ...

2011-05-01

182

GPRS Requirements. Dutch Smart Meter Requirements. Version 3.0. Final Status  

Energy Technology Data Exchange (ETDEWEB)

This document defines the requirements for the GPRS (General Packet Radio Service) infrastructure as part of the Dutch Smart Meter Specification. In this document all requirements originating from the NTA 8130, or additionally surveyed by a delegation of the Dutch grid operators, are presented in tables. Each requirement is tightly connected to one or more business use cases presented in the document. The ultimate goal of this procedure is to reduce ambiguity of the requirements due to a better understanding of the requirements.

2010-03-15

183

Enabling Technologies for Petascale Electromagnetic Accelerator Simulation  

Energy Technology Data Exchange (ETDEWEB)

The SciDAC2 accelerator project at SLAC aims to simulate an entire three-cryomodule radio frequency (RF) unit of the International Linear Collider (ILC) main Linac. Petascale computing resources supported by advances in Applied Mathematics (AM) and Computer Science (CS) and INCITE Program are essential to enable such very large-scale electromagnetic accelerator simulations required by the ILC Global Design Effort. This poster presents the recent advances and achievements in the areas of CS/AM through collaborations.

2007-11-09

184

Device for the inspection of curved pipes in steam raising units  

Energy Technology Data Exchange (ETDEWEB)

The chain of eddy current probes and a film cassette probe, which responds to radiation from a radio-active source in one of the heat exchanger pipes is examined. The probes are moved by nylon pipes on both ends of the chain through the pipe to be examined. The nylon pipes are bent off load. In this way the probes on the chain will adjust near to the plane of bending of the pipes to be tested.

1980-01-03

185

Carcinogenesis of inhaled radio daughters with uranium ore dust in beagle dogs  

International Nuclear Information System (INIS)

Daily exposures of adult beagle dogs to inhaled radon daughters and to uranium ore dust for 4-1/2 to 6 yr have produced respiratory tract carcinomas, at similar cumulative working level months (WLM) of exposures to those which induced carcinomas in uranium miners. Biological data from the beagle-dog experiments can therefore be used for prediction of carcinogenic risk under changing exposure conditions in future uranium miners.

1977-05-01

186

CRC handbook of biological effects of electromagnetic fields  

Energy Technology Data Exchange (ETDEWEB)

This book presents the current knowledge about the effects of electromagnetic fields on living matter. The three-part format covers dielectric permittivity and electrical conductivity of biological materials; effects of direct current and low frequency fields; and effects of radio frequency (including microwave) fields. The parts are designed to be consulted independently or in sequence, depending upon the needs of the reader. Useful appendixes on measurement units and safety standards are also included.

1986-01-01

187

Active RF filter for high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

A new technique is described in this paper for a general active radio frequency (RF) filter trap that can be used for suppressing noise or interference on high voltage (HV) transmission lines. The technique exploits the Miller effect of an RF amplifier in conjunction with a special sensing circuit, and is potentially far more economical to implement than conventional techniques that use passive HV filter components.

1993-07-01

188

The Vertical Stellar Kinematics in Face-On Barred Galaxies: Estimating the Ages of Bars  

CERN Document Server

In order to perform a detailed study of the stellar kinematics in the vertical axis of bars, we obtained high signal-to-noise spectra along the major and minor axes of the bars in a sample of 14 face-on galaxies, and used them to determine the line of sight stellar velocity distribution, parameterized as Gauss-Hermite series. With these data, we developed a diagnostic tool that allows one to distinguish between recently formed and evolved bars, as well as estimate their ages, assuming that bars form in vertically thin disks, recognizable by low values for the vertical velocity dispersion sigma_z. Through N-body realizations of bar unstable disk galaxies we could also check the time scales involved in the processes which give bars an important vertical structure. We show that sigma_z in evolved bars is roughly around 100 Km/s, which translates to a height scale of about 1.4 Kpc, giving support to scenarios in which bulges form through disk ...

2005-01-01

189

The Outermost Ejecta of Type Ia Supernovae  

CERN Document Server

The properties of the highest velocity ejecta of normal Type Ia supernovae (SNe Ia) are studied via models of very early optical spectra of 6 SNe. At epochs earlier than 1 week before maximum, SNe with a rapidly evolving Si II 6355 line velocity (HVG) have a larger photospheric velocity than SNe with a slowly evolving Si II 6355 line velocity (LVG). Since the two groups have comparable luminosities, the temperature at the photosphere is higher in LVG SNe. This explains the different overall spectral appearance of HVG and LVG SNe. However, the variation of the Ca II and Si II absorptions at the highest velocities (v >~ 20,000 km/s) suggests that additional factors, such as asphericity or different abundances in the progenitor white dwarf, affect the outermost layers. The C II 6578 line is marginally detected in 3 LVG SNe, suggesting that LVG undergo less intense burning. The carbon mass fraction is small, only less than 0.01 near the ...

2007-01-01

190

N-body Models of Extended Clusters  

CERN Document Server

We use direct N-body simulations to investigate the evolution of star clusters with large size-scales with the particular goal of understanding the so-called extended clusters observed in various Local Group galaxies, including M31 and NGC6822. The N-body models incorporate a stellar mass function, stellar evolution and the tidal field of a host galaxy. We find that extended clusters can arise naturally within a weak tidal field provided that the tidal radius is filled at the start of the evolution. Differences in the initial tidal filling-factor can produce marked differences in the subsequent evolution of clusters and the size-scales that would be observed. These differences are more marked than any produced by internal evolution processes linked to the properties of cluster binary stars or the action of an intermediate-mass black hole, based on models performed in this work and previous work to date. Models evolved in a stronger tidal field show that extended ...

2010-01-01

191

Industry Expectations from New Construction Engineers and Managers: Curriculum Improvement  

Science.gov (United States)

In an era of unprecedented technological advancement and economic expansion, construction practice continues to evolve but construction education has not changed appreciably since the 1990s. This schism has prompted industry, government, and other key constituents to question the relevancy and efficacy of current programs. The Accreditation Board for Engineering and Technology (ABET) Engineering Criteria 2000 and the American Council for Construction Education (ACCE) emphasizes outcomes over process, and provides an opportunity for stakeholders to help universities define educational goals and objectives and design a curriculum to meet the desired outcomes. While the need for curriculum modification has been acknowledged, the industry position was amorphous and anecdotal and therefore difficult to address. Qualitative methodologies such as formal surveys and structured interviews can be used to capture and quantify industry expectations of the needed attributes ...

2009-10-14

192

Dynamic nucleation of new grains in magnesium alloy during hot deformation  

Energy Technology Data Exchange (ETDEWEB)

Microstructure evolution under hot deformation was investigated in compression of a magnesium alloy AZ31 at 673 K (0.73T{sub m}). Two kinds of samples were machined along the parallel and transverse direction of the extruded rods. New fine grains are evolved at corrugated grain boundaries at low strains and developed rapidly in grain interiors in the medium range of strain, finally leading to a roughly full evolution of equiaxial fine grains. Kink bands are evolved at corrugated grain boundaries and in grain interiors at low strains. The boundary misorientation of kink band increases rapidly with increasing strain. These characteristics of new grain evolution process are not changed by the orientation of the samples, while the flow behaviors clearly depend on it. It is concluded that new grain evolution can be controlled by a deformation-induced continuous reaction resulting in grain fragmentation by kink bands, i.e. continuous dynamic ...

2003-07-01

193

Antihemostatic molecules from saliva of blood-feeding arthropods.  

Science.gov (United States)

The ability to feed on vertebrate blood has evolved many times in various arthropod clades. Each time this trait evolves, novel solutions to the problem posed by vertebrate hemostasis are generated. Consequently, saliva of blood-feeding arthropods has proven to be a rich source of antihemostatic molecules. Vasodilators include nitrophorins (nitric oxide storage and transport heme proteins), a variety of peptides that mimic endogenous vasodilatory neuropeptides, and proteins that catabolize or sequester endogenous vasoconstrictors. A variety of platelet aggregation inhibitors antagonize platelet responses to wound-generated signals, including ADP, thrombin, and collagen. Anticoagulants disrupt elements of both the intrinsic and extrinsic pathways. Molecular approaches (termed 'sialomics') to characterize the full inventory of mRNAs transcribed in salivary glands have revealed a surprising level of complexity within a single species. Multiple ...

2005-01-01

194

`Ecological forestry' and eucalypt forests managed for wood production in south-western Australia  

British Library Electronic Table of Contents (United Kingdom)

The model of `ecological forestry' has evolved as a part of the development of the concept of ecosystem management. `Ecological forestry' emphasises that manipulation of a forest ecosystem should consider, and as far as practicable work within the limits of, natural disturbance patterns prior to extensive human alteration of the landscape. This paper evaluates the extent to which forest management practices in jarrah (Eucalyptus marginata) and karri (Eucalyptus diversicolor) forests of south-western Australia align with this view of the characteristics and appropriate silviculture of `ecological forestry'. Characteristics and appropriate silviculture of `ecological forestry' are evaluated in relation to (i) the stand level decisions of stand structure and harvest timing and (ii) the landsc...

2007-01-01

195

The lateral hypothalamus as integrator of metabolic and environmental needs: From electrical self-stimulation to opto-genetics  

British Library Electronic Table of Contents (United Kingdom)

As one of the evolutionary oldest parts of the brain, the diencephalon evolved to harmonize changing environmental conditions with the internal state for survival of the individual and the species. The pioneering work of physiologists and psychologists around the middle of the last century clearly demonstrated that the hypothalamus is crucial for the display of motivated behaviors, culminating in the discovery of electrical self-stimulation behavior and providing the first neurological hint accounting for the concepts of reinforcement and reward. Here we review recent progress in understanding the role of the lateral hypothalamic area in the control of ingestive behavior and the regulation of energy balance. With its vast array of interoceptive and exteroceptive afferent inputs and its equ...

2011-01-01

196

Stem cells: Research tools and clinical treatments  

British Library Electronic Table of Contents (United Kingdom)

Abstract The term -stem cell- most commonly refers to embryonic stem cells, particularly in the lay media; however, it also describes other cell types. A stem cell represents a cell of multi-lineage potential with the ability for self-renewal. It is now clear that the plasticity and immortality of a given stem cell will depend on what type of stem cell it is, whether an embryonic stem cell, a fetal-placental stem cell or an adult stem cell. Stem cells offer great promise as cell-based therapies for the future. With evolving technology, much of the socio-political debate regarding stem cells can now be avoided.

2011-01-01

197

Single and binary star evolution  

International Nuclear Information System (INIS)

After presenting a general account of the observed global properties of single stars of low, intermediate, and high mass, together with their theoretical Hertzsprung-Russell diagram evolution, attention is given to the observed properties of various evolved close binaries and to an assessment of the value of comparisons between observation and crude theory in characterizing the physics of mass transfer within interacting binary systems. Detailed consideration is then undertaken of such topics as stellar evolution in globular clusters, interior star changes due to nucleosynthesis and mixing, asymptotic giant branch stars of intermediate mass, the response of white dwarfs in binary systems to mass accretion, and scenarios for binary star evolution tending toward close white dwarf pairs.

198

Simple method for the high-temperature isolation of /sup 111/In from silver  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative high-temperature isolation of /sup 111/In from silver irradiated by ..cap alpha..-particles into a gas phase containing a mixture of HCl and H/sub 2/O with a total pressure of about 3 Pa for these gases. It is shown that the indium evolved into the gas phase probably occurs in the form of at least three compounds, viz.., the trichloride, monochloride, and oxychloride, which have adsorption temperatures on quartz of around 385, 475, and 655 K, respectively. All these compounds are readily washed from the surface of quartz apparatus by a weak (0.05 M) solution of hydrochloric acid.

1987-07-01

199

Scaling and performance of a 3-D radiation hydrodynamics code on message-passing parallel computers: final report  

Energy Technology Data Exchange (ETDEWEB)

This report details an investigation into the efficacy of two approaches to solving the radiation diffusion equation within a radiation hydrodynamic simulation. Because leading-edge scientific computing platforms have evolved from large single-node vector processors to parallel aggregates containing tens to thousands of individual CPU's, the ability of an algorithm to maintain high compute efficiency when distributed over a large array of nodes is critically important. The viability of an algorithm thus hinges upon the tripartite question of numerical accuracy, total time to solution, and parallel efficiency.

1999-10-28

200

Nuclear material accountability by isotope dilution mass spectrometry  

International Nuclear Information System (INIS)

This paper discusses the mass spectrometric system that has been developed at the ICPP (Idaho Chemical Processing Plant) to meet the multiple constraints of U accountability, high sample load, and plant process control. The measurement system must produce high-quality accountability results while maintaining high sample throughput and reasonable turnaround time. The mass spectrometric system that has evolved to meet these demands includes extensive operator training, routine quality control checks, and continuing review of performance. 7 refs.

1981-07-13

201

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

Energy Technology Data Exchange (ETDEWEB)

The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

1985-05-01

202

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

International Nuclear Information System (INIS)

The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

203

Historical Analysis of Investment in Solar Energy Technologies (2000-2007)  

Energy Technology Data Exchange (ETDEWEB)

The solar energy industry experienced unprecedented growth in the eight years from 2000 to 2007, with explosive growth occurring in the latter half of this period. From 2004 to 2007, global private sector investment in solar energy increased by almost twenty-fold, marking a dramatic increase in the short span of four years. This paper examines the timing, magnitude, focus and location of various forms of investment in the solar energy sector. It analyzes their trends to provide an understanding of the growth of the solar industry during the past eight years and to identify emerging themes in this rapidly evolving industry.

2008-12-01

204

Heavy fermion behavior in Ce(Ni_xPd_1_-_x)_2Si_2  

International Nuclear Information System (INIS)

Measurements of the magnetic susceptibility #chi#, specific heat C, and thermoelectric power S were carried out for the solid solution Ce(Ni_xPd_1_-_x)_2Si_2 (0#<=#x#<=#1). With increasing x, the ground state changes from an antiferromagnetic Kondo state (x<0.2) to an intermediate valence state (x>0.3). The heavy fermion state was found to evolve at the crossover concentration at x=0.2, where the long-range magnetic order seems to disappear. [copyright] 2001 American Institute of Physics.

2001-06-01

205

Evolution of the primary components of massive binary stars in the case of Roche lobe overflow after main-sequence evolution  

International Nuclear Information System (INIS)

The components with masses 32 and 64M _s_u_n, evolved with the matter mixing in the semiconvective zone and filling their Roche lobes, after the main-sequence evolution overflow their Roche lobes and lose matter during the first part of the helium core burning. After the overflow end, the components lose the matter by stellar wind. The components shrink in the nuclear timescale. At first, they have the blue supergiant character with anomalous CNO abundance, then - the Wolf-Rayet stars character.

206

Controllable growth and magnetic properties of nickel nanoclusters electrodeposited on the ZnO nanorod template  

International Nuclear Information System (INIS)

The ZnO nanorods were used as a template to fabricate nickel nanoclusters by electrodeposition. The ZnO nanorod arrays act as a nano-semiconductor electrode for depositing metallic and magnetic nickel nanoclusters. The growth sites of Ni nanoclusters could be controlled by adjusting the applied potential. Under -1.15 V the Ni nanoclusters could be grown on the tips of ZnO nanorods. On increasing the potential to be more negative the ZnO nanorods were covered by Ni nanoclusters. The magnetic properties of the electrodeposited Ni nanoclusters also evolved with the applied potentials.

2009-12-09

207

Computer simulation and scientific visualization  

Energy Technology Data Exchange (ETDEWEB)

The simulation of processes in engineering and the physical sciences has progressed rapidly over the last several years. With rapid developments in supercomputers, parallel processing, numerical algorithms and software, scientists and engineers are now positioned to quantitatively simulate systems requiring many billions of arithmetic operations. The need to understand and assimilate such massive amounts of data has been a driving force in the development of both hardware and software to create visual representations of the underling physical systems. In this paper, and the accompanying videotape, the evolution and development of the visualization process in scientific computing will be reviewed. Specific applications and associated imaging hardware and software technology illustrate both the computational needs and the evolving trends. 6 refs.

1990-01-01

208

Asymptotic behavior of homogeneous cosmological models in the presence of a positive cosmological constant  

Energy Technology Data Exchange (ETDEWEB)

We examine the late-time behavior of initially expanding homogeneous cosmological models satisfying Einstein's equation with a positive cosmological constant ..lambda... It is shown that such models of all Bianchi types except IX exponentially evolve toward the de Sitter solution, with time scale (3/..lambda..)/sup 1/2/. The behavior of Bianchi type-IX universes is similar, provided that ..lambda.. is sufficiently large compared with spatial-curvature terms. Thus, a positive cosmological constant provides an effective means of isotropizing homogeneous universes.

1983-10-15

209

Asymptotic behavior of homogeneous cosmological models in the presence of a positive cosmological constant  

International Nuclear Information System (INIS)

We examine the late-time behavior of initially expanding homogeneous cosmological models satisfying Einstein's equation with a positive cosmological constant #LAMBDA#. It is shown that such models of all Bianchi types except IX exponentially evolve toward the de Sitter solution, with time scale (3/#LAMBDA#)/sup 1/2/. The behavior of Bianchi type-IX universes is similar, provided that #LAMBDA# is sufficiently large compared with spatial-curvature terms. Thus, a positive cosmological constant provides an effective means of isotropizing homogeneous universes.

210

Application aspects of the static frequency converter system  

Energy Technology Data Exchange (ETDEWEB)

The use of reversible pump/turbine sets in pumped storage has created a requirement for rapid reversibility. Softstart technology, based on static frequency converters (SFC) has evolved to such an extent that it is now the best choice for serving this purpose, both from a technical and from an economic point of view. The objective of our paper is to give the owners of pumped storage plants and those persons responsible for the selection, the operation or the maintenance of the electrical equipment the necessary insight into the SFC functions, features and all other application related aspects, to facilitate their decision making process. Case studies are included.

1995-12-31

211

THE EVOLUTION OF THE KINEMATICS OF NEBULAR SHELLS IN PLANETARY NEBULAE IN THE MILKY WAY BULGE  

International Nuclear Information System (INIS)

We study the line widths in the [O III]#lambda#5007 and H#alpha# lines for two groups of planetary nebulae in the Milky Way bulge based upon spectroscopy obtained at the Observatorio Astronomico Nacional in the Sierra San Pedro Martir (OAN-SPM) using the Manchester Echelle Spectrograph. The first sample includes objects early in their evolution, having high H#beta# luminosities, but [O III]#lambda#5007/H#beta# < 3. The second sample comprises objects late in their evolution, with He II #lambda#4686/H#beta#>0.5. These planetary nebulae represent evolutionary phases preceding and following those of the objects studied by Richer et al. in 2008. Our sample of planetary nebulae with weak [O III]#lambda#5007 has a line width distribution similar to that of the expansion velocities of the envelopes of asymptotic giant branch stars and shifted to systematically lower values as compared to the less evolved objects studied by Richer et al. The sample with strong He II ...

2010-06-10

212

Surface modification of functional self-assembled monolayers on 316L stainless steel via lipase catalysis.  

Science.gov (United States)

Lipase catalyzed esterification of therapeutic drugs to functional self-assembled monolayers (SAMs) on 316L stainless steel (SS) after assembly has been demonstrated. SAMs of 16-mercaptohexadecanoic acid (-COOH SAM) and 11-mercapto-1-undecanol (-OH SAM) were formed on 316L SS, and lipase catalysis was used to attach therapeutic drugs, perphenazine and ibuprofen, respectively, on these SAMs. The reaction was carried out in toluene at 60 degrees C for 5 h using Novozyme-435 as the biocatalyst. The FTIR spectra after surface modification of -OH SAMs showed the presence of the C=O stretching bands at 1745 cm(-1), which was absent in the FTIR spectra of -OH SAMs. Similarly, the FTIR spectra after the reaction of the -COOH SAM with perphenazine showed two peaks in the carbonyl region, a peak at 1764 cm(-1), which is the representative peak for the C=O stretching for esters. The second peak at 1681 cm(-1) is assigned to the C=O stretching of the remaining unreacted terminal COOH. XPS spectra ...

2006-01-31

213

Unification of Luminous Type 1 Quasars through CIV Emission  

CERN Document Server

Using a sample of 30,000 quasars from SDSS-DR7, we explore the range of properties exhibited by high-ionization, broad emission lines, such as CIV 1549. Specifically we investigate the anti-correlation between L_UV and emission line EQW (the Baldwin Effect) and the "blueshifting" of high-ionization emission lines. The blueshift of the CIV emission line is nearly ubiquitous, with a mean shift of 810 km/s for radio-quiet (RQ) quasars and 360 km/s for radio-loud (RL) quasars, and the Baldwin Effect is present in both RQ and RL samples. Composite spectra are constructed as a function of CIV emission line properties in attempt to reveal empirical relationships between different line species and the SED. Within a two-component disk+wind model of the broad emission line region (BELR), where the wind filters the continuum seen by the disk component, we find that RL quasars are consistent with being dominated by the disk component, while BALQSOs are ...

2010-01-01

214

The Distribution and Condition of the Warm Molecular Gas in Abell 2597 and Sersic 159-03  

CERN Document Server

We have used the SINFONI integral field spectrograph to map the near-infrared K-band emission lines of molecular and ionised hydrogen in the central regions of two cool core galaxy clusters, Abell 2597 and Sersic 159-03. Gas is detected out to 20 kpc from the nuclei of the brightest cluster galaxies and found to be distributed in clumps and filaments around it. The ionised and molecular gas phases trace each other closely in extent and dynamical state. Both gas phases show signs of interaction with the active nucleus. Within the nuclear regions the kinetic luminosity of this gas is found to be somewhat smaller than the current radio luminosity. Outside the nuclear region the gas has a low velocity dispersion and shows smooth velocity gradients. There is no strong correlation between the intensity of the molecular and ionised gas emission and either the radio or X-ray emission. The molecular gas in Abell 2597 and Sersic 159-03 is well described ...

2010-01-01

215

Surface modification of titanium by radio frequency plasma nitriding  

Energy Technology Data Exchange (ETDEWEB)

Radio frequency (RF) plasma nitriding using different input plasma processing powers (250-600 W) improves the surface of titanium by forming hard phases of TiN, Ti{sub 2}N, and Ti (N) into the surface. The characteristics of the compound layer have been investigated by optical microscopy, microhardness measurements, and X-ray diffraction. The effect of plasma power on the sample temperature, electron temperature, and plasma density was studied using Langmuir double probe. The measured surface hardness value of the compound layer is 2190 HV 0.1 for treated sample at plasma power 500 W. The compound thickness continuously increases as the plasma power increases. The highest nitriding rate of 5.88 {mu}m{sup 2}/s was recorded when the input plasma power was adjusted at 550 W. This high nitriding rate of treated titanium samples is ascribed to the high concentration of active nitrogen species in the plasma atmosphere and the formed microcracks near to the surface of the ...

2006-02-21

216

Surface modification of titanium by radio frequency plasma nitriding  

International Nuclear Information System (INIS)

Radio frequency (RF) plasma nitriding using different input plasma processing powers (250-600 W) improves the surface of titanium by forming hard phases of TiN, Ti_2N, and Ti (N) into the surface. The characteristics of the compound layer have been investigated by optical microscopy, microhardness measurements, and X-ray diffraction. The effect of plasma power on the sample temperature, electron temperature, and plasma density was studied using Langmuir double probe. The measured surface hardness value of the compound layer is 2190 HV 0.1 for treated sample at plasma power 500 W. The compound thickness continuously increases as the plasma power increases. The highest nitriding rate of 5.88 #mu#m"2/s was recorded when the input plasma power was adjusted at 550 W. This high nitriding rate of treated titanium samples is ascribed to the high concentration of active nitrogen species in the plasma atmosphere and the formed microcracks near to the surface of the sample ...

2006-02-21

217

Second mission of North-Cotentin radio-ecology group. The uncertainty calculation; Deuxieme mission du Groupe Radio-ecologie Nord-Cotentin. Le calcul d'incertitude  

Energy Technology Data Exchange (ETDEWEB)

The present study treats only the collective risk of ex-utero leukaemia associated with the routine releases of the nuclear industrial installations of the North Cotentin (0.0009 cases over the considered period) the uncertainty on the contribution to the collective risk of the incidents and the accidents of the nuclear installations (notably the drilling of the pipe of release in sea arisen in 1979-1980 and the fire of the waste silo on January 6. 1981, for the reprocessing plant of La Hague has not been considered. Only 45% of the risk are taken into account by the study. Every calculated value remains very inferior to the number of leukemia cases observed (4 cases observed for two expected cases) and to the risk of radioinduced leukemia any merged exposure sources, that is to say 0.84 cases. It appears thus not very probable that the nuclear installations of the North - Cotentin can explain the tendency to the excess of observed leukaemia. The limits of the study become attached for ...

2003-03-15

218

Radioiodinated peanut lecitin: A potential radiopharmaceutical for immunodetection of carcinoma expressing the T antigen  

International Nuclear Information System (INIS)

The Thomsen-Friedenreich (T) antigen, #betta#-D-Gal-(1->3)-#alpha#-D-GalNAc, is exposed in reactive form on many human adenocarcinomata, but not on corresponding benign tissues. Peanut lectin (PNA) has a strong binding affinity for the T antigen and reportedly binds preferentially to certain malignant tissues. We investigated the potential of radio-labelled PNA as a tumour localising agent in an animal model system using a mouse lymphoma (RI) shown to bind fluorescein-labelled PNA in vitro. The radio-iodinated lectin showed good tumour localisation and rapid blood clearance. Clear images of tumours were obtained, in serial scintigraphic imaging, by 24 and 48 h. No blood background subtraction was necessary. Biodistribution studies revealed tumour to blood ratios in mice were 6:1 (at 24 h) and 17:1 (at 48 h), and tumour to muscle ratios were 34:1 (at 24 h) and 40:1 (at 48 h). Rapid in vivo breakdown of _1_2_5I-PNA led to some localisation of ...

1983-01-01

219

Radio-frequency plasma nitriding and nitrogen plasma immersion ion implantation of Ti-6Al-4V alloy  

Energy Technology Data Exchange (ETDEWEB)

Nitrogen ion implantation improves the wear resistance of Ti-6Al-4V alloys by forming a hard TiN superficial passivation layer. However, the thickness of the layer formed by traditional ion implantation is typically 100-200 nm and may not be adequate for many industrial applications. We propose to use radio-frequency (RF) plasma nitriding and nitrogen plasma immersion ion implantation (PIII) to increase the layer thickness. By using a newly designed inductively coupled RF plasma source and applying a series of negative high voltage pulses to the Ti-6Al-4V samples. RF plasma nitriding and nitrogen PIII can be achieved. Our process yields a substantially thicker modified layer exhibiting more superior wear resistance characteristics, as demonstrated by data from micro-hardness testing, pin-on-disc wear testing, scanning electron microscopy (SEM), as well as Auger electron spectroscopy (AES). The performance of our newly developed inductively coupled RF plasma source ...

1997-09-01

220

Radio-frequency plasma nitriding and nitrogen plasma immersion ion implantation of Ti-6Al-4V alloy  

International Nuclear Information System (INIS)

Nitrogen ion implantation improves the wear resistance of Ti-6Al-4V alloys by forming a hard TiN superficial passivation layer. However, the thickness of the layer formed by traditional ion implantation is typically 100-200 nm and may not be adequate for many industrial applications. We propose to use radio-frequency (RF) plasma nitriding and nitrogen plasma immersion ion implantation (PIII) to increase the layer thickness. By using a newly designed inductively coupled RF plasma source and applying a series of negative high voltage pulses to the Ti-6Al-4V samples. RF plasma nitriding and nitrogen PIII can be achieved. Our process yields a substantially thicker modified layer exhibiting more superior wear resistance characteristics, as demonstrated by data from micro-hardness testing, pin-on-disc wear testing, scanning electron microscopy (SEM), as well as Auger electron spectroscopy (AES). The performance of our newly developed inductively coupled RF plasma source ...

1996-09-15

221

Radio Frequency Plasma Applications for Space Propulsion  

Energy Technology Data Exchange (ETDEWEB)

Recent developments in solid-state radio frequency (RF) power technologies allow for the practical consideration of RF heated plasmas for space propulsion. These technologies permit the use of any electrical power source, de-couple the power and propellant sources, and allow for the effcient use of both the propellant mass and power. Effcient use of the propellant is obtained by expelling the rocket exhaust at the highest possible velocity, which can be orders of magnitude higher than those achieved in chemical rockets. Handling the hot plasma exhaust requires the use of magnetic nozzles, and the basic physics of ion detachment from the magnetic eld is discussed. The plasma can be generated by RF using helicon waves to heat electrons. Further direct heating of the ions helps to reduce the line radiation losses, and the magnetic geometry is tailored to allow ion cyclotron resonance heating. RF eld and ion trajectory calculations are presented to give a reasonably ...

1999-09-13

222

Properties of ZnO thin films prepared by radio-frequency plasma beam assisted laser ablation  

International Nuclear Information System (INIS)

Zinc oxide thin films were obtained by laser ablation of a Zn target in oxygen reactive atmosphere, the oxygen being supplied either by a standard gas inlet valve or from a radio-frequency (rf) oxygen plasma. Pt-coated silicon and MgO were used as substrates. The influence of the deposition parameters as laser wavelength (266, 355, 1064 nm), laser fluence (1.5-20 J/cm2) and oxygen pressure (1-60 Pa) was studied. The influence of the rf plasma beam addition on the morphological proprieties of zinc oxide films was particularly investigated, simultaneously with several configurations of the direction of the ablation plasma, the rf plasma beam and the substrate. The obtained films, with thicknesses in the range of 50 nm to 1 ?m have been characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), transmission electron microscopy (TEM).

2005-07-15

223

Photovoltaic Technologies Beyond the Horizon: Optical Rectenna Solar Cell, Final Report, 1 August 2001-30 September 2002  

Energy Technology Data Exchange (ETDEWEB)

ITN Energy Systems is developing next-generation solar cells based on the concepts of an optical rectenna. ITN's optical rectenna consists of two key elements: (1) an optical antenna to efficiently absorb the incident solar radiation, and (2) a high-frequency metal-insulator-metal (MIM) tunneling diode that rectifies the AC field across the antenna, providing DC power to an external load. The combination of a rectifying diode at the feedpoints of a receiving antenna is often referred to as a rectenna. Rectennas were originally proposed in the 1960s for power transmission by radio waves for remote powering of aircraft for surveillance or communications platforms. Conversion efficiencies greater than 85% have been demonstrated at radio frequencies (efficiency defined as DC power generated divided by RF power incident on the device). Later, concepts were proposed to extend the rectennas into the IR and optical region of the ...

2003-02-01

224

Orion's Bar: Physical Conditions across the Definitive H+ / H0 / H2 Interface  

CERN Document Server

Previous work has shown the Orion Bar to be an interface between ionized and molecular gas, viewed roughly edge on, which is excited by the light from the Trapezium cluster. Much of the emission from any star-forming region will originate from such interfaces, so the Bar serves as a foundation test of any emission model. Here we combine X-ray, optical, IR and radio data sets to derive emission spectra along the transition from H+ to H0 to H2 regions. We then reproduce the spectra of these layers with a simulation that simultaneously accounts for the detailed microphysics of the gas, the grains, and molecules, especially H2 and CO. The magnetic field, observed to be the dominant pressure in another region of the Orion Nebula, is treated as a free parameter, along with the density of cosmic rays. Our model successfully accounts for the optical, IR and radio observations across the Bar by including a significant magnetic pressure and also heating ...

2008-01-01

225

Measurements of radio propagation in rock salt for the detection of high-energy neutrinos  

CERN Document Server

We present measurements of the transmission of radio/microwave pulses through salt in the Cote Blanche salt mine operated by the North American Salt Company in St. Mary Parish, Louisiana. These results are from data taken in the southwestern region of the 1500 ft. (457 m) deep level of the mine on our third and most recent visit to the mine. We transmitted and received a fast, high-power, broadband pulse from within three vertical boreholes that were drilled to depths of 100 ft. (30 m) and 200 ft. below the 1500 ft. level using three different pairs of dipole antennas whose bandwidths span 125 to 900 MHz. By measuring the relative strength of the received pulses between boreholes with separations of 50 m and 169 m, we deduce the attenuation of the signal attributed to the salt medium. We fit the frequency dependence of the attenuation to a power law and find the best fit field attenuation lengths to be 93 \\pm 7 m at 150 MHz, 63 \\pm 3 m at 300 MHz, and 36 \\pm 2 m ...

2008-01-01

226

High-resolution beta imaging; L'imagerie beta haute resolution  

Energy Technology Data Exchange (ETDEWEB)

For many years, {beta} radioactivity has been used to label molecules and follow them in various biological processes. {beta} imaging is obtained by autoradiography. Classically made on films or on photographic emulsions, autoradiography is now supplanted by radio-imagers which are very performing. The phosphor-imager, {beta}-imager and {mu}-imager are the systems mainly used today and their operating principles and properties are compared. The great advantages of these imagers are: their rapidity to obtain results and their reliability for absolute quantification. All emitters ({beta}{sup -}, {beta}{sup -} -{gamma} and {beta}{sup +}) are detectable as well as the gamma emitters of nuclear medicine, by means of their low energy electrons ejected during y emission. Phosphor-imager is well suited to energetic tracers and large series of experiments. Real time radio-imagers ({beta}-imager and {mu}-imager) are preferred to verify experimental ...

2007-04-15

227

Evaluation of influence of fertilizers in radium concentration from tomato culture; Avaliacao da influencia dos fertilizantes nos teores de radio encontrados na cultura do tomate  

Energy Technology Data Exchange (ETDEWEB)

The fertilizer contribution to radio uptake by tomato plants was assessed. Tomato and soil samples from four different plantations were analyzed: two using organic fertilizer and two using phosphate fertilizer. The Ra concentrations in eight of the most used tomato fertilizers were determined. The concentration values ranged from 14 to 221 Bq/kg of Ra-226 and from 25 to 176 Bq/kg of Ra-228. Owing to the low Ra concentration and to the used fertilizer quantities, the fertilizers would not increase significantly the Ra soil concentration. However, the highest soil to plant concentration ratios were found in the plantations using phosphate fertilizers. This outcome pointed out the higher Ra availability in the phosphate fertilizer plantations than in the organic fertilizer plantations, showing a possible positive influence of phosphate fertilizers for the tomato Ra uptake. Due to the phosphate fertilizer used, the dose could increase from 0,05 Sv/year to 0,24 Sv/year. ...

2001-07-01

228

Electrical properties of ultra-thin oxynitrided layer using N{sub 2}O plasma in inductively coupled plasma chemical vapor deposition for non-volatile memory on glass  

Energy Technology Data Exchange (ETDEWEB)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics ...

2007-06-04

229

Electrical properties of ultra-thin oxynitrided layer using N_2O plasma in inductively coupled plasma chemical vapor deposition for non-volatile memory on glass  

International Nuclear Information System (INIS)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics ...

2007-06-04

230

Electric field measurement on time domain generated by corona on insulators on distribution systems  

Energy Technology Data Exchange (ETDEWEB)

Radio interference and TV interference are being a problem in urban and rural areas. This interference is generated by high voltage transmission lines as well as distribution lines. The radio noise can be produced by polluted or damaged insulators, and by metal parts of the distribution lines. The corona effect on the surface of the dielectric material produces high frequency electromagnetic fields during the ionization and during the recombination period. Fields of different intensity are produced by positive voltage and negative voltage. The insulator flashover (leaking current) also produces electromagnetic fields. A new technique to measure these fields was developed. This technique measures the radiated fields on time domain and on frequency domain. This permits us to characterize the radiated field and thus identify the type of the source. Several measurements were done varying the type of the RF generator, i.e., new insulator and broken ...

1996-12-31

231

Effect of gamma radiation on the survival of fungal and actinomycetal florae contaminating medicinal plants  

Energy Technology Data Exchange (ETDEWEB)

This study evaluates the effect of gamma radiation on the viability of fungi and actinomycetes that contaminate medicinal plants. The relationship between the total lipids of some fungi and actinomycetes and their sensitivity to gamma radiation is also investigated. The data reveal that the viable counts of these florae decrease approximately exponentially with the radiation dose, the effective dose for the elimination of these microorganisms being about 5 kGy for all the medicinal plants under study. Response of pure cultures of fungi and actinomycetes isolated from medicinal plants to increasing absorbed doses of gamma radiation indicate that an increase in radioresistance is in the following order: Streptomyces rimosus, Fusarium solani, Nocardia kuroishii. F. oxysporum, A. fumigatus, A. flavus, A. parasiticus and A. ochraceus. The total lipid contents of molds and actinomycetes have been reported to be increased by increasing the radio-resistance of ...

1997-01-01

232

Development of nanometer resolution C-Band radio frequency beam position monitors in the Final Focus Test Beam  

Energy Technology Data Exchange (ETDEWEB)

Using a 47 GeV electron beam, the Final Focus Test Beam (FFTB) produces vertical spot sizes around 70 nm. These small beam sizes introduce an excellent opportunity to develop and test high resolution Radio Frequency Beam Position Monitors (RF-BPMs). These BPMs are designed to measure pulse to pulse beam motion (jitter) at a theoretical resolution of approximately 1 nm. The beam induces a TM{sub 110} mode with an amplitude linearly proportional to its charge and displacement from the BPM's (cylindrical cavity) axis. The C-band (5,712 MHz) TM{sub 110} signal is processed and converted into beam position for use by the Stanford Linear Collider (SLC) control system. Presented are the experimental procedures, acquisition, and analysis of data demonstrating resolution of jitter near 25 nm. With the design of future e{sup +}e{sup -} linear colliders requiring spot sizes close to 3 nm, understanding and developing RF-BPMs will be essential in resolving and ...

1998-08-01

233

DETECTION OF AN X-RAY PULSATION FOR THE GAMMA-RAY PULSAR CENTERED IN CTA 1  

International Nuclear Information System (INIS)

We report the detection of X-ray pulsations with a period of ?315.87 ms from the 2009 XMM-Newton observation for the radio-quiet ?-ray pulsar, LAT PSR J0007+7303, centered in the supernova remnant CTA 1. The detected pulsed period is consistent with the ?-ray periodicity at the same epoch found with the Fermi Gamma-ray Space Telescope. The broader sinusoidal structure in the folded light curve of the X-ray emission is dissimilar to that of the ?-ray emission, and the phase of the peak is about 0.5 shifting from the peak in the ?-ray bands, indicating that the main component of the X-rays originates from different sites of the pulsar. We conclude that the main component of the X-ray pulsation is contributed by the thermal emission from the neutron star. Although with a significantly different characteristic age, PSR J0007+7303 is similar to Geminga in emission properties of X-rays and ?-rays; this makes PSR J0007+7303 the second radio-quiet ...

2010-12-10

234

Comparison of LaBr_3:Ce and NaI(Tl) Scintillators for Radio-Isotope Identification Devices  

International Nuclear Information System (INIS)

Lanthanum halide (LaBr_3:Ce) scintillators offer significantly better resolution (< 3% at 662 keV) relative to NaI(Tl) and have recently become commercially available in sizes large enough for the handheld, Radio-Isotope Identification Device (RIID) market. Drawbacks to lanthanum halide detectors, however, include internal radioactivity contributing to spectral counts, and a low-energy response which can cause detector resolution to be worse than that of NaI(Tl) below 100 keV. To study the potential of this new material for RIIDs we performed a series of measurements comparing a 1.5 x 1.5-inch LaBr_3:Ce detector with an Exploranium GR-135 RIID, which contains a 1.5 x 2.2-inch NaI(Tl) detector. Measurements were taken for short timeframes, as typifies RIID usage. Measurements included examples of naturally occurring radioactive material (NORM), typically found in cargo, and special nuclear materials. Some measurements were non-contact, involving short distances ...

2005-10-23

235

Calibrating Emission Lines as Quasar Bolometers  

CERN Document Server

Historically, emission lines have been considered a valuable tool for estimating the bolometric thermal luminosity of the accretion flow in AGN, $L_{bol}$. We study the reliability of this method by comparing line strengths to the optical/UV continuum luminosity of SDSS DR7 radio quiet quasars with $0.4radio loud quasars as an illustrative ...

2011-01-01

236

An optimization method for reference dose point of rectum in brachytherapy of gynecological neoplasms  

International Nuclear Information System (INIS)

Rectum reference dose points have a direct impact on the morbidity seen in gynecological intracavitaty radiotherapy. The aim of this study is to obtain less morbidity by marking rectum with radio opaque solution. Fourteen patients with gynecological cancer who underwent external radiotherapy received 15 Gray (Gy) intracavitary radiotherapy. During the internal radiotherapy planning, radio opaque solution has been administered into the rectum to observe it on lateral radiogram. Thus rectum reference dose point and five points were marked at sites nearest to the sources. Nucletron Planning system was used for obtaining three-dimensional planning. After therapy patients were followed at every three months. Median follow-up was 18 months. Most frequently observed morbidities were grade 1-2 rectitis and cystitis in six patients. As a result, more accurate rectum dose values and less factors causing dose changing can provide better results for ...

2002-05-01

237

Adaptive response of the chicken embryo to low doses of x-irradiation  

Energy Technology Data Exchange (ETDEWEB)

Chicken embryos were x-irradiated in ovo with 5-30 cGy (=priming dose) at the 13th-15th day of development. After 3-48 h, brain- and liver-cell suspensions were x-irradiated in vitro with (challenge) doses of 4-32 Gy. Significantly less radiation damage was observed when the radiation response was measured by scheduled DNA synthesis, nucleoid sedimentation and viscosity of alkaline cell lysates 12-36 h after the priming exposure. In vivo, pre-irradiation with 10 cGy enhanced regeneration as evidenced by the DNA content of chicken embryo brain and liver 24 h following a challenge dose of 4 Gy. From nucleoid sedimentation analyses in brain and liver cells immediately after irradiation with 16 Gy and after a 30-min repair period in the presence of aphidicolin, dideoxythymidine and 3-aminobenzamide or in the absence of these DNA repair inhibitors, it is concluded that a reduction of the initial radiation damage is the dominant mechanism of the ``radio-adaptive`` ...

1995-08-01

238

A sensitive submillimetre survey of Broad Absorption Line quasars  

CERN Document Server

Using the SCUBA bolometer array on the JCMT, we have carried out a submillimetre survey of Broad Absorption Line quasars (BALQs). The sample has been chosen to match, in redshift and optical luminosity, an existing benchmark 850um sample of radio-quiet quasars, allowing a direct comparison of the submm properties of BAL quasars relative to the parent radio-quiet population. We reach a submm limit 1.5mJy at 850um, allowing a more rigorous measure of the submm properties of BAL quasars than previous studies. Our submm photometry complements extensive observations at other wavelengths, in particular X-rays with Chandra and mid-infrared with Spitzer. To compare the 850um flux distribution of BALQs with that of the non-BAL quasar benchmark sample, we employ a suite of statistical methods, including survival analysis and a novel Bayesian derivation of the underlying flux distribution. Although there are no strong grounds for rejecting the null ...

2006-01-01

239

A microcontroller-based data-acquisition system for meteorological station monitoring  

International Nuclear Information System (INIS)

This paper presents a study of feasibility of different existing methodologies linked to field's data acquisition from remote meteorological stations. The data transmission serves to collect field's meteorological information, such as temperature, humidity and radiation. In our study the experimental data is registered in a weather station located about 100 km from University of Almeria. Various existing techniques are studied, especially Radio, GSM (global system of mobile communication) and GPRS (general packet radio service). In the result of these studies has been designed a system of field's data acquisition (herein referred as Meteologger) which we are going to present in this paper. The system is based on an ATmega 16 microcontroller, which scans 8 sensors together at any programmable intervals. This paper presents the study of the mentioned project, application and some main characteristics of the prototype system and its program. We ...

2008-12-01

240

The luminosity function of cluster pulsars  

CERN Document Server

We study luminosities of millisecond pulsars in globular clusters by fitting the observed luminosity distribution with single and double power laws. We use simulations to model the observed distribution as the brighter part of some parent distribution for Terzan 5 and try to find a model which simultaneously agrees with the observed diffuse radio flux, total predicted number of pulsars and observed luminosity distribution. We find that wide ranges of parameters for log-normal and power-law distributions give such good models. No clear difference between the luminosity distributions of millisecond pulsars in globular clusters and normal disk pulsars was seen.

2010-01-01

241

The effect of high voltage transmission lines on agricultural land values in minnesota  

Energy Technology Data Exchange (ETDEWEB)

Overhead, high power transmission lines have secured rights of way on agricultural lands in Minnesota. The economic impact of such utility crossings, including effects on land price, was investigated. Sale records and survey data were analyzed. Buyers, sellers, and brokers were interviewed concerning inconvenience, radio interference, appearance, and loss of irrigation possibilities due to the transmission lines. In nine affected sales, there was only one case in which less money was indicated for the farm because of the presence of a transmission line.

1981-04-01

242

The effect of high voltage transmission lines on agricultural land values in Minnesota  

Energy Technology Data Exchange (ETDEWEB)

Overhead, high power transmission lines have secured rights of way on agricultural lands in Minnesota. The economic impact of such utility crossings, including effects on land price, was investigated. Sale records and survey data were analyzed. Buyers, sellers, and brokers were interviewed concerning inconvenience, radio interference, appearance, and loss of irrigation possibilities due to the transmission lines. In nine affected sales, there was only one case in which less money was indicated for the farm because of the presence of a transmission line.

1981-04-01

243

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

CERN Document Server

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

1999-01-01

244

Recent observations of Cassiopeia A  

International Nuclear Information System (INIS)

During the last few years radio and X-ray astronomers have produced high-resolution imagery of the remnant of Cas A. Since the most recent published optical photographs of Cas A date back to 1975 it seemed worthwhile to present new optical results based on plates obtained with the 5-m Hale telescope in 1976, 1977, and 1980. The major changes that have taken place in Cas A during the last decade are: (1) A broken shell of fast-moving knots has formed along the southern and SW rim of the remnant and (2) A number of blue (oxygen-rich) filaments have developed to the north of the centre of Cas A. (Auth.).

245

Radio-frequency and microwave load comprising a carbon-bonded carbon fiber composite  

Energy Technology Data Exchange (ETDEWEB)

A billet of low-density carbon-bonded carbon fiber (CBCF) composite is machined into a desired attenuator or load element shape (usually tapering). The CBCF composite is used as a free-standing load element or, preferably, brazed to the copper, brass or aluminum components of coaxial transmission lines or microwave waveguides. A novel braze method was developed for the brazing step. The resulting attenuator and/or load devices are robust, relatively inexpensive, more easily fabricated, and have improved performance over conventional graded-coating loads.

1998-01-01

246

Radio-Frequency Beam Conditioner for Fast-Wave Free-Electron Generators of Coherent Radiation  

Energy Technology Data Exchange (ETDEWEB)

A method for conditioning electron beams is proposed, making use of the TM{sub 210} mode of microwave cavities, to reduce the axial velocity spread within the beam, in order to enhance gain in resonant electron beam devices, such as the free-electron laser (FEL). Effectively, a conditioner removes the restriction on beam emittance. The conditioner is analyzed using a simple model for beam transport and ideal RF cavities. Analysis of an FEL is employed to evaluate performance with reduced axial velocity spread. Examples of FELs are presented showing the distinct advantage of conditioning.

1991-07-01

247

Radio frequency He/sup -/ source and a source of negative ions by cesium sputtering  

Energy Technology Data Exchange (ETDEWEB)

Two sources of negative ions are described. An rf source produces up to 14 ..mu..A beams of He/sup -/ by charge exchange in Rb vapor. The other Source of Negative Ions by Cesium Sputtering (SNICS) produces a wide variety of negative ion beams in the ..mu..A range. Two important features of SNICS are its simple, compact construction and its very good beam emittance (2 to 4..pi..mm mrad MeV/sup 1/2/). Both sources have lifetimes >200 hours and they are used extensively on the Wisconsin EN tandem.

1981-04-01

248

RBS Characterization of Yttrium Iron Garnet Thin Films  

International Nuclear Information System (INIS)

Magnetic materials such as yttrium iron garnet (YIG) are of great importance for its magneto-optic properties and for their potential applications in the domain of optical telecommunications. The deposition of thin films of YIG, on quartz or GGG (gadolinium gallium garnet) substrate, was performed using radio frequency non reactive magnetron sputtering, followed by high temperature annealing which is needed to enhance the crystallinity of the layers. Rutherford backscattering spectrometry RBS was used to determine the thickness and stoichiometry of the performed layers in order to investigate correlations between growth conditions and the quality of the final material. RBS measurements showed the influence of the deposition time and the temperature substrate on the film growth and its stoichiometry. (author)

2008-12-13

249

Pure NQR quantum computing  

Energy Technology Data Exchange (ETDEWEB)

It is shown that pure NQR can be utilized as a platform for quantum computing without applying a high external magnetic field. By exciting each resonance transition between quadrupole energy levels with two radio-frequency fields differing in phase and direction, the double degeneracy of the spin energy spectrum in an electric field gradient is removed. As an example, in the case of I=7/2 (nuclei {sup 133}Cs or {sup 123}Sb) the energy spectrum has eight levels which can be used as three qubits. (orig.)

2002-07-01

250

Phase formation in gas-phase combustion and pyrolysis reactions under spark and radio-frequency discharge conditions  

British Library Electronic Table of Contents (United Kingdom)

Doped ultrafine silicon dioxide powder with a narrow particle size distribution was obtained by RF discharge-stimulated dichlorosilane (SiH2C) oxidation at a low pressure using isobutylene as the combustion inhibitor and chromium hexacarbonyl (Cr(CO)6) as the dopant. The formation and morphology of the ultrafine particles are governed by the parameters of the RF discharge and by the chemical mechanism of the combustion reaction yielding the aerosol. Submicron-sized filamentous carbon structures can be obtained by isobutylene decomposition under spark discharge conditions in the presence of a molybdenum metal catalyst.

2009-01-01

251

Operational status of the Brookhaven National Laboratory Accelerator Test Facility  

International Nuclear Information System (INIS)

Initial design parameters and early operational results of a 50 MeV high brightness electron linear accelerator are described. The system utilizes a radio frequency electron gun operating at a frequency of 2.856 GHz and a nominal output energy of 4.5 MeV followed by two, 2#pi#/3 mode, disc loaded, traveling wave accelerating sections. The gun cathode is photo excited with short (6 psec) laser pulses giving design peak currents of a few hundred amperes. The system will be utilized to carry out infra-red FEL studies and investigation of new high gradient accelerating structures.

1990-06-11

252

On the Bottom Magnetic Fields of the Millisecond Pulsars  

CERN Document Server

The magnetic field strengths of most millisecond pulsars(MSP) are about $10^{8-9}$ Gauss. The accretion induced magnetic field evolution scenario here concludes that the field decay is invesely related to the accreted mass and the minimum field or bottom field stops at about $10^{8}$ Gauss if accreted with the Eddington accretion rate, which is proportionally related with the accretion rate as $\\dot{M}^{1/2}$. The possibility of the low field $\\sim 10^{7}$ Gauss MSPs has been proposed for the future radio observation.

2003-01-01

253

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

254

Josephson effect mm-wave receivers  

International Nuclear Information System (INIS)

Josephson effect heterodyne mixers with external local oscillators are very promising low noise mm-wave receivers for applications such as radio astronomy. Experiments at 36 GHz have shown that both the noise and the conversion efficiency of mixers made using Nb point contacts are in quantitative agreement with values calculated from the resistively shunted junction (RSJ) model. Preliminary measurements at 140 GHz suggest that this agreement extends to higher frequencies. In this paper the theoretical limits to the sensitivity of such receivers are explored as a function of the signal frequency. (Auth.).

255

Initial RF measurements of the CW normal-conducting RF injector  

Energy Technology Data Exchange (ETDEWEB)

The LANL 2.5-cell, normal-conducting radio-frequency (NCRF) injector has been fabricated. We present initial results of low-power RF measurements (cavity Q, cavity field map, coupling beta, etc.) of the NCRF injector. The measured cavity Q and relative fields are found to be in good agreement with the design calculations and earlier measurements of Glidcop properties. However, the coupling beta of the ridge-loaded waveguides is found to be significantly higher than the design point. The impact of these low-power measurement results on the planned high-power RF and electron beam tests will be discussed.

2008-01-01

256

High-current negative-ion beam transport  

Energy Technology Data Exchange (ETDEWEB)

The requirements for transporting high-current, negative-ion beams are presented with particular emphasis on applications involving negative-hydrogen-ion beams. In addition to the usual matching and steering problems, particular attention must be paid to beam emittance growth in the transport system. Depending on the application, a number of approaches have been developed using both magnetic and electric lenses. I discuss the design considerations for transporting and matching these beams to radio-frequency quadrupole accelerators, and present a survey of the various types of beamlines now used for negative-ion beams.

1992-10-05

257

Guidelines on the medical therapy of persons accidentally overexposed to ionizing radiations. External contamination  

International Nuclear Information System (INIS)

The document represents a guide for the external decontamination of persons accidentally radio contaminated due to the use, production or transport of radioactive materials. The general conditions, from the medical point of view, to be kept in mind, in the event of accidental overexposures as decontamination treatment and the handling of samples are detailed throughout report. The external contamination without injury in skin or with wound its considered. The distribution of measures and responsibilities for the therapy of the irradiated patients with radioactive materials are enumerated. The preparations of decontaminate solutions are detailed in this work. Moreover, forms for the reception, physical evaluation of the patient and external contamination are presented. (author)

258

Determination of the content of elements in some wild medicinal plants of Uzbekistan by radioactivation analysis  

Energy Technology Data Exchange (ETDEWEB)

The authors have developed a complex of activation methods of analysis using a nuclear reactor (nuclear activation analysis) and a cyclotron (charged-particle activation analysis). The methods have been used to determine the concentrations of more than 20 elements in five medicinal plants native to Uzbekistan: Syrian rue (Peganum harmala L.), plantain (Plantago lanceolata), peppermint (Mentha piperata L.), sage (Salvia officinalis L.), and ziziphora (Ziziphora bungeana Yur.). The results of radio-activation analysis were compared with the results of standard spectral analysis performed in another laboratory and the accuracy of the procedures developed was evaluated on the basis of the results.

1987-06-01

259

Cosmological surveys with the Australian Square Kilometre Array Pathfinder  

CERN Document Server

This is a design study into the capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) in performing a full-sky low redshift neutral hydrogen survey, termed WALLABY, and the potential cosmological constraints one can attain from measurement of the matter power spectrum. We find that the full sky survey will likely attain 600,000 redshifts which, when combined with expected Planck CMB data, will constrain the Dark Energy equation of state to 20%, for the first time making cosmological constraints from radio observations competitive with the best existing optical surveys.

2011-01-01

260

Conceptual design of a nuclear reactor facility for medical and biological purposes  

Energy Technology Data Exchange (ETDEWEB)

Optimal neutron energy for boron neutron capture therapy (BNCT) has been studied. Epithermal neutron is superior to thermal neutrons in treating deep-seated tumors. Design of the epithermal neutron column for BNCT has been performed by using a two-dimensional transport calculation code. Aluminum and heavy water are used as moderation materials. A thermal neutron column is also designed using heavy water as thermalization material. The configuration of the facility for treatment and research of BNCT and also for basic radio-biological studies of neutrons has been presented.

1981-09-01

261

Conceptual design of a nuclear reactor facility for medical and biological purposes  

International Nuclear Information System (INIS)

Optimal neutron energy for boron neutron capture therapy (BNCT) has been studied. Epithermal neutron is superior to thermal neutrons in treating deep-seated tumors. Design of the epithermal neutron column for BNCT has been performed by using a two-dimensional transport calculation code. Aluminum and heavy water are used as moderation materials. A thermal neutron column is also designed using heavy water as thermalization material. The configuration of the facility for treatment and research of BNCT and also for basic radio-biological studies of neutrons has been presented. (author).

262

CT findings of foreign bodies in the chest: a pictorial essay  

Energy Technology Data Exchange (ETDEWEB)

The most common causes of tracheobronchial foreign bodies are peanuts in children, and meat and dentures in adults. The most common causes of esophageal foreign bodies are coins in children and meat in adults. It is passable to diagnose a foreign body by visualization on a chest radiograph, if the foreign bodies are radio opaque. However, if the foreign bodies are radiolucent and the patients do not remember the history of aspiration, it is important to evaluate CT findings for foreign bodies and their complications. We describe the CT findings of various thoracic foreign bodies in children and adults.

2008-05-15

263

Bone geometry, biomechanics, and mineral content of the distal radius in uremic patients with severe hyperparathyroidism; Valutazione delle proprieta' geometriche, biomeccaniche e osteodensitometriche del radio ultradistale mediante tomografia computerizzata quantitativa periferica nei pazienti uremici affetti da iperparatiroidismo grave  

Energy Technology Data Exchange (ETDEWEB)

Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis. [Italian] Gli autori propongono un metodo non invasivo per studiare la densita' minerale e le caratteristiche geometriche e biomeccaniche dell'osso nei pazienti uremici affetti da iperparatiroidismo secondario grave.

1999-04-01

264

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.

265

The Hubble Space Telescope Wide Field Camera 3 Early Release Science Data: Panchromatic Faint Object Counts From 0.2-2 Micron To Ab=26-27 Mag  

Science.gov (United States)

We describe the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) Early Release Science (ERS) observations in the GOODS-South field. The new WFC3 ERS data provide calibrated, drizzled mosaics with FHWM=0.07--0.15" in the near-UV (filters F225W, F275W, and F336W) and near-IR (F098W, F125W, and F160W) in typically 2 orbits per filter. Together with the existing HST/ACS GOODS-S mosaics in the BVi'z' filters, the 10-band ERS data cover 40-50 sq. arcmin to AB=26-27.0 mag (10-sigma for point sources). In this poster, we describe the: (1) scientific rationale, data taking and reduction procedures of the WFC3 ERS mosaics; (2) object cataloging and star-galaxy separation techniques used in these 10 different filters; (3) reliability and completeness of the 10-band object catalogs from the ERS mosaics; (4) object counts in 10 different filters from 0.2-1.7 microns to AB=26.0-27.0 mag; and (5) the full-color 10-band ERS images. We discuss the panchromatic structure for a variety of ...

2010-01-01

266

The operation status and prospect of radioisotope production facility in HANARO  

Energy Technology Data Exchange (ETDEWEB)

Researches and production of radio-isotopes, radio-pharmaceuticals and cold kits are carried out in the Radio-isotope Production Facility (RIPF). Four concrete hot cells in Bank-1 are to produce the Ir-192 source for NDT. Eleven lead hot cells in Bank-2 are to produce Ho-166, Cr-51, P-32/33, Tc-99m, Lu-177, Sr-90/Y-90 and W-188/Re-188 for research purpose. Six lead hot cells in Bank-3 are used for the production of I-131 for diagnosis and therapy of cancer in the hospital. A hot cell in Bank-3 is also utilized for the research of I-125 and Br-82. Four lead hot cells in Bank-4 are utilized for the production of Mo-99/Tc-99m generators since 2005. The major systems including the Heat and Ventilated Air Conditioning (HVAC) system and the air cleaning system such as charcoal and HEPA filter trains to filter the radioactive contaminants are in operation. So are the systems such as power supply and distribution system, UPS, fire ...

2008-11-15

267

Study of radionuclide contributing to dose rates in 540 MWe plant environment  

International Nuclear Information System (INIS)

Tarapur Atomic Power Station Unit-4 is first 540 MWe pressurized heavy water reactor in India. It achieved criticality on 06th March 2005 and then operated at full power i.e 500 MWe. Radiation workers during the normal operation and reactor shutdown are exposed to radiation field. The control of dose rates and the collective dose of the radiation workers is most important for the best performance of the reactor. Experience gained during the operation of the 220 MWe reactors has shown that the Moderator system, primary heat transport system, annulus gas system and moderator cover gas system are the main systems contributing to the dose rate and collective dose. In order to identify the radio nuclides contributing to the radiation field, study was undertaken at TAPS Unit-4. Various samples from the Moderator, primary heat transport system, annulus gas system and moderator cover gas system were collected and analysed for the spectrometric analysis. This paper ...

2005-11-23

268

Global positioning automatic vehicle location system  

Energy Technology Data Exchange (ETDEWEB)

Los Alamos National Laboratory (LANL) is a unique facility covering over 43 square miles. The Emergency Management and Response Office (EM&R) is required to respond, provide Incident Command (IC), and coordination for all Laboratory emergencies. This requires IC`s and support staff to respond to the actual scene of the incident. Since the IC is under numerous constraints and stress, the office wanted the capability of locating the EM&R vehicles on an electronic map. An automated vehicle location (AVL) system was required for the additional safety of the emergency response personal. The requirements for the AVL system include total automatic tracking and low cost. After careful consideration, it was determined that the most efficient and cost effective system would be based on packet radio technology as the transmission media. The location is determined by the Department of Defense Global Positioning System (GPS). The system that was designed and constructed ...

1997-03-01

269

Variation in male reproductive traits among three bitterling fishes (Acheilognathinae: Cyprinidae) in relation to the mating system  

British Library Electronic Table of Contents (United Kingdom)

Male traits that correlate with fertilization success include testis size and structure, ejaculate size, ejaculation frequency, and sperm motility. Two hypotheses potentially explain interspecific differences in these traits: sperm competition and sperm limitation. We examined variation in six traits associated with fertilization success in three closely-related species of bitterling fish; the European bitterling (Rhodeus amarus), the Chinese rose bitterling (Rhodeus ocellatus), and the Chinese bitterling (Rhodeus sinensis). Interspecific differences indicated that the three study species have evolved different sperm allocation strategies. Rhodeus amarus displayed the most developed reproductive apparatus with a number of traits associated with both high levels of sperm production and fert...

2011-01-01

270

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

International Nuclear Information System (INIS)

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

2006-07-01

271

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.

272

The Application of AHP Model to Guide Decision Makers: A Case Study of E-banking Security  

CERN Document Server

Changes in technology have resulted in new ways for bankers to deliver their services to costumers. Electronic banking systems in various forms are the evidence of such advancement. However, information security threats also evolving along this trend. This paper proposes the application of Analytic Hierarchy Process (AHP) methodology to guide decision makers in banking industries to deal with information security policy. The model is structured according aspects of information security policy in conjunction with information security elements. We found that cultural aspect is valued on the top priority among other security aspects, while confidentiality is considered as the most important factor in terms of information security elements.

2010-01-01

273

Study on the solid state reaction between bilayered Pd/Au films and silicon substrates  

British Library Electronic Table of Contents (United Kingdom)

Bilayers of pure palladium and gold films were evaporated alternatively on (100) and (111) monocrystalline silicon substrates. After annealing, in a vacuum furnace from 100 to 650degreeC during 30min, the growth sequence of the Pd2Si and PdSi phases that evolved as the result of the diffusion reaction was examined by means of Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD), whereas the surface morphology was investigated by scanning electron microscopy (SEM) technique. The effect of the intermediate gold layer is investigated in order to test its effectiveness as barrier for Cu and Si atoms interdiffusion and its influence on the morphology of the formed palladium silicides. The effect of substrate orientation on the palladium silicides growth and formation was also e...

2006-01-01

274

Structural aging program to assess the adequacy of critical concrete components in nuclear power plants  

International Nuclear Information System (INIS)

The Structural Aging (SAG) Program is carried out by the Oak Ridge National Laboratory (ORNL) under sponsorship of the United States Nuclear Regulatory Commission (USNRC). The Program has evolved from preliminary studies conducted to evaluate the long-term environmental challenges to light-water reactor safety-related concrete civil structures. An important conclusion of these studies was that a damage methodology, which can provide a quantitative measure of a concrete structure's durability with respect to potential future requirements, needs to be developed. Under the SAG Program, this issue is being addressed through: establishment of a structural materials information center, evaluation of structural component assessment and repair technologies, and development of a quantitative methodology for structural aging determinations. Progress to date of each of these activities is presented as well as future plans. 7 refs., 5 figs.

1989-08-14

275

Streamlining lead discovery by aligning in silico and high-throughput screening  

British Library Electronic Table of Contents (United Kingdom)

Lead discovery in the pharmaceutical environment is largely an industrial-scale process in which it is typical to screen 1-5 million compounds in a matter of weeks using High Throughput Screening (HTS). This process is a very costly endeavor. Typically a HTS campaign of 1 million compounds will cost anywhere from $500000 to $1000000. There is consequently a great deal of pressure to maximize the return on investment by finding fast and more effective ways to screen. A panacea that has emerged over the past few years to help address this issue is in silico screening. In silico screening is now incorporated in all areas of lead discovery; from target identification and library design, to hit analysis and compound profiling. However, as lead discovery has evolved over the past few years, so h...

2006-01-01

276

Stellar Pollution in the Solar Neighborhood  

CERN Document Server

We study spectroscopically determined iron abundances of 642 solar-type stars to search for the signature of accreted iron-rich material. We find that the metallicity [Fe/H] of a subset of 466 main sequence stars, when plotted as a function of stellar mass, mimics the pattern seen in lithium abundances in open clusters. Using Monte Carlo models we find that, on average, these stars have accreted about 0.4 Earth masses of iron while on the main sequence. A much smaller sample of 19 stars in the Hertzsprung gap, which are slightly evolved and whose convection zones are significantly more massive, have lower average [Fe/H], and their metallicity shows no clear variation with stellar mass. These findings suggest that terrestrial-type material is common around solar type stars.

2000-01-01

277

Stability of the viscously spreading ring  

CERN Document Server

We study analytically and numerically the stability of the pressure-less, viscously spreading accretion ring. We show that the ring is unstable to small non-axisymmetric perturbations. To perform the perturbation analysis of the ring we use a stretching transformation of the time coordinate. We find that to 1st order, one-armed spiral structures, and to 2nd order additionally two-armed spiral features may appear. Furthermore, we identify a dispersion relation determining the instability of the ring. The theoretical results are confirmed in several simulations, using two different numerical methods. These computations prove independently the existence of a secular spiral instability driven by viscosity, which evolves into persisting leading and trailing spiral waves. Our results settle the question whether the spiral structures found in earlier simulations of the spreading ring are numerical artifacts or genuine instabilities.

2003-01-01

278

Simulating Large-scale Structure  

CERN Document Server

After two decades of direct dynamical simulation of large-scale structure in the universe, it is safe to say the subject is now mature. Still, there are parts of the problem that are less well developed than others. In general, the collisionless dynamics of the dark matter component is better understood than the collisional gas dynamics of the baryonic component. In situations where the gas dynamics is relatively simple, such as the Lyman-$\\alpha$ forest and the intracluster medium in X-ray clusters, our ability to reproduce observational data has evolved rapidly, and the interpretive and predictive power of such experiments should now be taken seriously. A comparison of twelve gas dynamic codes to the problem of forming a single X-ray cluster shows that numerical inaccuracies are modest (typically below ten percent), leaving missing physics as the main source for large systematic differences between theory and observation. Galaxy formation, being more complex, is ...

1998-01-01

279

Sell lumens, not kilowatts: The future for electric utilities  

Energy Technology Data Exchange (ETDEWEB)

The key to the future for electric utilities will not be found in legislation or regulation. Title VII of the Energy Policy Act of 1992 will prove to be just as ineffectual in improving the industry's position as was the Public Utility Regulatory Policies Act of 1978. These legislative palliatives, which produced so much commotion and so many reams of heated commentary, are largely irrelevant to a successful future for electric utilities. The key will be found in economics, not in law, and the future will lie in completing Thomas A. Edison's century-old vision for the industry, half of which the industry has heretofore ignored. The industry must embrace the complete vision and evolve from electric utilities into [open quotes]end-use energy utilities.[close quotes

1993-04-01

280

Security features of a nuclear material accounting system  

Energy Technology Data Exchange (ETDEWEB)

The Los Alamos Nuclear Material Accounting and Safeguards System (MASS) is a near-real-time accountability system for bulk materials, discrete items, and material undergoing dynamic processing. MASS has evolved from an eighty-column card based process control system to a very sophisticated computer system. The security of the MASS computer system is provide through various access controls. There are two kinds of access control to be addressed. They are physical access control to the hardware which make up the system, and access control to the software. There are many features which provide a measure of security to the hardware that will be discussed. Access to the software is controlled by a security password. Access to various transaction activities in the system is controlled through the level of MASS user privilege. Details of MASS user privilege will be discussed.

1988-01-01

281

Safety testing of 18650-style Li-Ion cells  

Energy Technology Data Exchange (ETDEWEB)

To address lithium-ion cell safety issues in demanding power applications, electrical and thermal abuse tests were performed on 18650 sized cells. Video and electrically monitored abuse tests in air included short circuit, forced overcharge, forced reversal, and controlled overheating (thermal) modes. Controlled overheating tests to 200 C were performed in a sealed chamber under a helium atmosphere and the gases released from the cell during thermal runaway were analyzed at regular intervals using gas chromatography and mass spectrometry. In addition to alkane and alkene solvent breakdown fragments, significant H{sub 2} was detected and evidence that HF was evolved was also found.

2000-06-08

282

Relationships between Film Chemistry, Structure, and Mechanical Properties in Titanium Oxide  

Energy Technology Data Exchange (ETDEWEB)

Titanium oxides were grown anodically to selected final potentials on grade II polycrystalline titanium under different anodization rates. XPS and RBS results show that the oxide consists of primarily TiO2 with a non-stoichiometric oxide/metal interface, with the slower growth rate associated with a thicker layer at the interface. Characterization using TEM reveals that the structure of the oxide evolves from a primarily amorphous phase to islands of crystallites in an amorphous matrix, to an entirely crystalline phase by increasing the polarization potential. Slower growth rates tend to remain crystalline at higher potentials. The mechanical strength of oxide films extracted from load-depth data by nanoindentation varies dramatically for oxide films grown by different rates at 9.4 V, and to a lesser extent at lower potentials. The variation of film strength is associated with both compositional and structural characteristics.

2001-01-01

283

Reactive ceramics of CeO{sub 2}-MO{sub x} (M=Mn, Fe, Ni, Cu) for H{sub 2} generation by two-step water splitting using concentrated solar thermal energy  

Energy Technology Data Exchange (ETDEWEB)

The addition of MO{sub x} (M: di- or tri-valent transition metal ion) into cerium dioxide (CeO{sub 2}) enhanced the ability of CeO{sub 2} for the oxygen (O{sub 2})-releasing reaction at lower temperature and swift hydrogen (H{sub 2})-generation reaction. CeO{sub 2}-MO{sub x} (M=Mn, Fe, Ni, Cu) reactive ceramics having high melting points were synthesized with the combustion method from their nitrates for solar H{sub 2} production. The prepared CeO{sub 2}-MO{sub x} samples were solid solutions between CeO{sub 2} and MO{sub x} with the fluorite structure through the X-ray diffractometry measurement. Two-step water-splitting reactions with CeO{sub 2}-MO{sub x} reactive ceramics proceeded at 1573-1773 K for the O{sub 2}-releasing step and at 1273 K for the H{sub 2}-generation step by irradiation of infrared image furnace as a solar simulator. The amounts of O{sub 2} evolved in the O{sub 2}-releasing reaction with CeO{sub 2}-MO{sub x} increased with an increase in the ...

2007-05-15

284

Quality engineering programme in the design process. A major utility 's experience  

International Nuclear Information System (INIS)

The paper describes the latest approach to quality engineering in the design process as applied by Ontario Hydro throughout the various phases of the project life cycle for Ontario Hydro generating stations and related facilities. Ontario Hydro has long recognized that the high quality and performance required in nuclear generating stations start in the design process and can best be achieved through an adequate and proper quality engineering programme in design. The current approach has evolved over a period of six years and represents a meaningful and effective series of requirements, functions and activities, which are used to ensure safety, reliability, economy and environmental acceptability of nuclear generating stations. (author).

285

Prospective Impacts of Electronic Textiles on Recycling and Disposal  

British Library Electronic Table of Contents (United Kingdom)

Summary Electronic textiles are a vanguard of an emerging generation of smart products. They consist of small electronic devices that are seamlessly embedded into clothing and technical textiles. E-textiles provide enhanced functions in a variety of unobtrusive and convenient ways. Like many high-tech products, e-textiles may evolve to become a mass market in the future. In this case, large amounts of difficult-to-recycle products will be discarded. That can result in new waste problems. This article examines the possible end-of-life implications of textile-integrated electronic waste. As a basis for assessment, the innovation trends of e-textiles are reviewed, and an overview of their material composition is provided. Next, scenarios are developed to estimate the magnitude of future e-tex...

2011-01-01

286

Proceedings of the Pacific Knowledge Acquisition Workshop 2004  

CERN Document Server

Artificial intelligence (AI) research has evolved over the last few decades and knowledge acquisition research is at the core of AI research. PKAW-04 is one of three international knowledge acquisition workshops held in the Pacific-Rim, Canada and Europe over the last two decades. PKAW-04 has a strong emphasis on incremental knowledge acquisition, machine learning, neural nets and active mining. The proceedings contain 19 papers that were selected by the program committee among 24 submitted papers. All papers were peer reviewed by at least two reviewers. The papers in these proceedings cover the methods and tools as well as the applications related to develop expert systems or knowledge based systems.

2005-01-01

287

Proceedings of the 23rd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting  

Energy Technology Data Exchange (ETDEWEB)

A compilation of technical papers, from the 23rd annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, is presented. Papers were given in the following categories: (1) developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) international and transnational applications of PTTI technology with emphasis on satellite laser tracking networks, GLONASS timing, comparison of national time scales and international communications; (3) applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) applications of PTTI technology to evolving military communications and navigation systems; and (5) dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, Loran, and synchronous communications satellites.

1992-07-01

288

Photovoltaics: Contract lists, fiscal year 1992  

Energy Technology Data Exchange (ETDEWEB)

US DOE`s Photovoltaics Program has helped photovoltaic technologies evolve from materials and concepts in laboratories to competitive products rolling off automated assembly lines. The program is working to expand industrial capacity while continuing basic and applied technology R and D. This document is a tabulation of photovoltaics R and D that were begun, continued, or completed during this period. National laboratories or industrial, academic, and nonprofit research institutions perform the RR and D activities. The document is organized first by directing organization, then by project title and individual task. Each listing provides the name of contractor, period of performance, funding, objectives, accoplishments, and FY 1993 milestones. An index of contractors is included. (DLC)

1993-03-01

289

Phenomenological models  

Energy Technology Data Exchange (ETDEWEB)

The biological effects of ionizing radiation exposure are the result of a complex sequence of physical, chemical, biochemical, and physiological interactions. One way to begin a search for an understanding of health effects of radiation is through the development of phenomenological models of the response. Many models have been presented and tested in the slowly evolving process of characterizing cellular response. A range of models covering different endpoints and phenomena has developed in parallel. Many of these models employ similar assumptions about some underlying processes while differing about the nature of others. An attempt is made to organize many of the models into groups with similar features and to compare the consequences of those features with the actual experimental observations. It is assumed that by showing that some assumptions are inconsistent with experimental observations, the job of devising and testing mechanistic models can be simplified. ...

1990-09-01

290

Phase Information and the Evolution of Cosmological Density Perturbations  

CERN Document Server

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel'dovich approximation as an initial motivation, we develop a statistic that quantifies the information content of the distribution of phases. Using numerical simulations beginning with more realistic Gaussian random-phase initial conditions, we show that the information content of the phases grows from zero in the initial conditions, first slowly and then rapidly when structures become non-linear. This growth of phase information can be expressed in terms of an effective entropy: Gaussian initial conditions are a maximum entropy realisation of the initial power spectrum, gravitational evolution decreases the phase entropy. We show that our definition of ...

2000-01-01

291

Multidate image analysis of forest degradation in equatorial Africa  

Energy Technology Data Exchange (ETDEWEB)

A section of the northern margin of the Guineo-Congolian rain forest of the Central African Republic is studied to determine to what extent deforestation is evolving. Three sites are presented to highlight the diversity in local environmental settings at the northern margin of the closed equatorial rain forest: the contiguous equatorial rain forest, the boundary between the closed rain forest and the grasslands, and a predominantly secondary grassland environment. Proven image processing procedures for determining land cover and vegetation vigor were applied to Landsat MSS data to determine land cover characteristics and identify alterations in land cover that indicate potentially degraded forest environments. Land cover was independently assessed using spectral signatures determined from a statistical clustering routine. The images presented and image analyses contribute insights and information to an ongoing effort to determine more reliable data on the status of ...

1990-12-01

292

Mucosal Inflammation in Spondylarthritides: Past, Present, and Future  

British Library Electronic Table of Contents (United Kingdom)

Spondylarthritides (SpA) and inflammatory bowel disease (IBD) are idiopathic, chronic inflammatory disorders. Although they are very distinct and well-defined entities, there is clinical and genetic evidence supporting some degree of overlap between the pathogenesis of the two. Subclinical gut inflammation is present in up to two thirds of all SpA patients and can evolve into IBD. This subclinical gut inflammation has been shown to be strongly associated with joint inflammation, providing a clue for a common pathophysiologic background. Despite extensive research progress in the field over the past few years, many questions remain unanswered. In this paper, we focus on the clinical, genetic, and pathophysiologic overlap of SpA and IBD. Furthermore, we discuss some of the targets that may i...

2011-01-01

293

Molecular phylogenetic relationships and phenotypic diversity in miniaturized toadlets, genus Brachycephalus (Amphibia: Anura: Brachycephalidae)  

British Library Electronic Table of Contents (United Kingdom)

Toadlets of the genus Brachycephalus are endemic to the Atlantic rainforests of southeastern and southern Brazil. The 14 species currently described have snout-vent lengths less than 18mm and are thought to have evolved through miniaturization: an evolutionary process leading to an extremely small adult body size. Here, we present the first comprehensive phylogenetic analysis for Brachycephalus, using a multilocus approach based on two nuclear (Rag-1 and Tyr) and three mitochondrial (Cyt b, 12S, and 16S rRNA) gene regions. Phylogenetic relationships were inferred using a partitioned Bayesian analysis of concatenated sequences and the hierarchical Bayesian method (BEST) that estimates species trees based on the multispecies coalescent model. Individual gene trees showed conflict and also va...

2011-01-01

294

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

295

Modeling dispersion and deposition of smoke generated from chemical fires  

British Library Electronic Table of Contents (United Kingdom)

Abstract Smoke is a mixture of toxic gases and suspended particulate matter of solids and liquids that evolves from a fire of flammable materials. This article presents real-time consequence modeling to track the concentration of individual species in smoke as well as its soot deposition. In the modeling process presented, the burning rate or vapor mass is fed into a combustion model in which the combustion of products has been identified and quantified along with the temperature of the fire. The output of the combustion model is the smoke that will be dispersed into the ambient. The fire geometry, which depends on the type of fire (e.g., pool or flare), is identified. A dispersion model with the capability of determining particulate deposition is then used for tracking the smoke plume. Th...

2011-01-01

296

Mobile offshore drilling rig newbuild and replacement cost functions  

British Library Electronic Table of Contents (United Kingdom)

Mobile offshore drilling rigs are used to drill, complete and workover wellbores in marine environments. The fleet that exists today consists of a wide variety of vessels built to various specifications over the past three decades, and because they operate in harsh, corrosive environments, they wear out structurally and require periodic maintenance. Rig designs have evolved with changes in operating requirements and new technology and rigs are frequently modified and upgraded, depending upon market conditions, operator preferences and other factors. The construction and replacement costs of offshore rigs are often used for management planning, financial valuation and insurance analysis, and because of the wide variety of designs, specifications and upgrades, cost estimates vary widely. In ...

2010-01-01

297

Microwave sintering of titanium diboride  

Energy Technology Data Exchange (ETDEWEB)

Titanium diboride was heated to high temperatures using microwaves. The highest temperature obtained was 2245/degree/C. Unfortunately, oxidation was a problem, especially at the higher temperatures, although an argon flush and a carbon getter were used. To completely stop oxidation, the oxygen potential must be below 10/sup /minus/18/ atmospheres. Using an argon flush and a carbon getter, titanium diboride was successfully densified to 82% of theoretical without measurable oxidation by heating with microwaves to 1860/degree/C. Density actually decreased upon reaching temperatures above 1860/degree/C due to void formation adjacent to the surface. Void formation is thought to be due to the formation of B/sub 2/O/sub 3/(g) which evolves rapidly above 1860/degree/C because of the loss of a TiO/sub 2/ protective film which melts at this temperature. 9 refs., 12 figs., 2 tabs.

1989-01-01

298

Metamorphosis of Confucian Heritage Culture and the possibility of an Asian education research methodology  

British Library Electronic Table of Contents (United Kingdom)

This paper opens with a critical analysis of a paradox in contemporary educational research in and about Confucian Heritage Culture (CHC): the assumption that national boundaries coincide with those of a distinct and homogeneous culture, which consistently renders a rather homogenous set of educational phenomena, and collides against a more widely accepted discourse - culture transcends geographical frontiers and is ever evolving in character. It is claimed that this paradox is due to the fact that a thin conception of CHC competes neck-and-neck with a thick conception of it. This paper also addresses the possibility of an ad hoc education research methodology in and about CHC and its compliance issues regarding the mainstream Western research dynamics and philosophy of science. Confucian ...

2011-01-01

299

Mental time travel and the shaping of language.  

Science.gov (United States)

Episodic memory can be regarded as part of a more general system, unique to humans, for mental time travel, and the construction of future episodes. This allows more detailed planning than is afforded by the more general mechanisms of instinct, learning, and semantic memory. To be useful, episodic memory need not provide a complete or even a faithful record of past events, and may even be part of a process whereby we construct fictional accounts. The properties of language are aptly designed for the communication and sharing of episodes, and for the telling of stories; these properties include symbolic representation of the elements of real-world events, time markers, and combinatorial rules. Language and mental time travel probably co-evolved during the Pleistocene, when brain size increased dramatically. PMID:18641975

2008-07-19

300

Mechanism of the accumulation effect in laser damage to polymers: appearance of microdamage due to an ionization absorption wave  

Energy Technology Data Exchange (ETDEWEB)

An investigation was made of the accumulation of laser damage to transparent polymers irradiated with nanosecond pulses from neodymium and ruby lasers. The damage was investigated by the method of scattering and luminescence in the visible and near ultraviolet parts of the spectrum. It was established that there were two stages in laser damage by repeated irradiation with pulses of intensity below the single-shot damage threshold. An absorbing defect evolved during the first stage in such a way as to create a thermal instability in the surrounding matrix. During the second stage this thermal instability caused spatial growth of laser damage because of propagation of an ionization-inducing absorption wave with a front traveling at the rate governed by the electron component of the thermal conductivity.

1984-04-01

301

Measuring interesting rules in Characteristic rule  

CERN Document Server

Finding interesting rule in the sixth strategy step about threshold control on generalized relations in attribute oriented induction, there is possibility to select candidate attribute for further generalization and merging of identical tuples until the number of tuples is no greater than the threshold value, as implemented in basic attribute oriented induction algorithm. At this strategy step there is possibility the number of tuples in final generalization result still greater than threshold value. In order to get the final generalization result which only small number of tuples and can be easy to transfer into simple logical formula, the seventh strategy step about rule transformation is evolved where there will be simplification by unioning or grouping the identical attribute. Our approach to measure interesting rule is opposite with heuristic measurement approach by Fudger and Hamilton where the more complex concept hierarchies, more interesting results are ...

2010-01-01

302

Luminescence dating  

International Nuclear Information System (INIS)

The luminescence techniques have evolved over the last 40 years to a powerful dating instrument in archaeology and geoscience. Depending on how the luminescence is stimulated, one distinguishes the phenomena of thermoluminescence (TL), optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL). Each of these phenomena has its specific potential for dating various archaeological materals in the time range from medieval back to palaeolithic periods, or, speaking in geological terms, for dating of Holocene and late Pleistocene objects. The OSL and IRSL techniques are sometimes treated together as 'optical dating'. The luminescence techniques differ from other major dating techniques, such as 14C, essentially by their applicability to inorganic materials, their wide age-range from about 100 years to more than 100,000 years and the kind of datable events which are the last exposure to heat or to light. (author). 10 refs., 3 figs.

303

Low power flux logging system for TAPS 3 and 4  

International Nuclear Information System (INIS)

This system provides data logging facility for axial profile and dynamic profile experiments during low power physics experiments. The data from Cobalt Self Powered Neutron Detectors (SPNDs) are logged via hardware consisting of PC plug-in cards and data of vanadium SPNDs are logged from the Flux Mapping System (FMS) network (multicast data). The data along with programmable details of the experiment is transferred to an Access Database. The system provides online displays and extensive reports from the Access Database as per the requirement from Reactor Physicists. This paper briefly describes the evolvement of requirements (from the experience of operation of TAPS 4 to TAPS 3), software architecture and design. (author)

2010-02-01

304

It's time for management version 2.0: Six forces redefining the future of modern management  

British Library Electronic Table of Contents (United Kingdom)

The body of knowledge known as ''management'' has evolved incrementally over the past 100 years through a variety of innovators, including: Frederick Taylor, Max Weber, Mary Parker Follett, Chester Barnard, William Ouchi and Tom Peters. While the miracle of management - its structures, processes and techniques - has provided humankind with quantum advances in standard of living, there is an emerging theme in the literature to suggest that ''Management 1.0'' founded within the industrial age paradigm has reached the limits of its relevance. This paper proposes that it is time to consider a new conceptualization - ''Management 2.0'' - based on the global, information age paradigm in which modern businesses compete. This paper examines six forces which are currently redefining the future of m...

2011-01-01

305

Is culture a determinant of financial development?  

British Library Electronic Table of Contents (United Kingdom)

This article investigates the missing link in the literature - whether informal institutions, or what is known as culture, can affect the level of financial development for a country? Our hypothesis stresses that the cultural dimensions of a country can have an impact on its financial set-up. We consider multiple dimensions of culture, identified in the literature by Tabellini (2008), to test our hypothesis. As culture evolves in the form of greater trust, control and other traits, individuals' attitudes towards financial market change, and they engage in greater financial transactions. This, in turn, leads to better financial development. Using quantile estimation technique for a cross section of 90 countries, we find that culture significantly influences the level of financial developmen...

2012-01-01

306

Investigation of heat transfer with boiling of cryogenic liquids on surfaces with capillary-porous coating  

Energy Technology Data Exchange (ETDEWEB)

Means of intensifying heat transfer with nucleate boiling, based on boiling under constrained conditions (in slots, on a capillary-porous surface) are the most promising since a high intensity of heat transfer is ensured. In the present work we attempt to evolve the main assumptions for the physical model of the process of vapour formation under constrained conditions and to extend them to the boiling of cryogenic liquids on surfaces with a capillary-porous deposit; also, the results are given of experimental investigations of heat transfer with the boiling of nitrogen, oxygen and hydrogen at atmospheric perssures and below on capillary-porous surfaces of various metals of different structure produced by an electric arc method of gasothermal spray coating.

1980-01-01

307

Initial grain size effect of dynamic recrystallization of magnesium alloy AZ31  

Energy Technology Data Exchange (ETDEWEB)

Dynamic development of new grain boundaries was studied in compression of a magnesium alloy AZ31 with initial grain sizes (D{sub 0}) of 22 {mu}m and 90 {mu}m at a temperature of 673 K. Kink bands are evolved near corrugated grain boundaries and in grain interiors at low strains accompanied with new fine grains. Kink bands are developed often perpendicular to the basal plane. The boundary misorientation of kink band as well as the volume fraction of new grains increases rapidly with increasing strain and approaches a saturation value in high strain. New fine grains are developed faster with decrease in the D{sub 0}. It is concluded that new grain evolution is controlled by a deformation-induced continuous reaction, i.e. continuous dynamic recrystallization (DRX). (orig.)

2003-07-01

308

Ideal MHD stability properties of pressure-driven modes in low shear tokamaks  

Energy Technology Data Exchange (ETDEWEB)

The role of shear in determining the ideal MHD stability properties of tokamaks is discussed. In particular, we assess the effects of low shear within the plasma upon pressure-driven modes. The standard ballooning theory is shown to break down, as the shear is reduced and the growth rate is shown to be an oscillatory function of n, the toroidal mode number, treated as a continuous parameter. The oscillations are shown to depend on both the pressure and safety-factor profiles. When the shear is sufficiently weak, the oscillations can result in bands of unstable n values which are present even when the standard ballooning theory predicts complete stability. These instabilities are named ''infernal modes.'' The occurrence of these instabilities at integer n is shown to be a sensitive function of q-axis, raising the possibility of a sharp onset as plasma parameters evolve. 20 refs., 31 figs.

1987-03-01

309

Homoclinic chaos and energy condition violation  

International Nuclear Information System (INIS)

In this letter we discuss the connection between so-called homoclinic chaos and the violation of energy conditions in locally rotationally symmetric Bianchi type IX models, where the matter is assumed to be nontilted dust and a positive cosmological constant. We show that homoclinic chaos in these models is an artifact of unphysical assumptions: it requires that there exist solutions with positive matter energy density #rho#>0 that evolve through the singularity and beyond as solutions with negative matter energy density #rho#<0. Homoclinic chaos is absent when it is assumed that the dust particles always retain their positive mass. In addition, we discuss more general models: for solutions that are not locally rotationally symmetric we demonstrate that the construction of extensions through the singularity, which is required for homoclinic chaos, is not possible in general.

2006-09-15

310

Galactic Cosmic Rays - Clouds Effect and Bifurcation Model of the Earth Global Climate. Part 1. Theory  

CERN Document Server

The possible physical linkage between galactic cosmic rays intensity and the Earth's cloud cover is discussed using the analysis of the first indirect aerosol effect (Twomey effect) and its experimental representation as the dependence of average cloud droplet effective radius on aerosol index characterizing the aerosol concentration in the atmospheric air column of unit section. It is shown that the basic kinetic equation of the Earth's climate energy-balance model is described by the bifurcation equation (with respect to the temperature of the Earth's surface) in the form of fold catastrophe with two governing parameters defining the variations of insolation and Earth's magnetic field (or galactic cosmic rays intensity in the atmosphere), respectively. The principle of hierarchical climatic models construction, which consists in the structural invariance of balance equations of these models evolving on the different time scales, is described. It means that if the ...

2008-01-01

311

From the podium to the PC: a study on various modalities of lecture delivery within an undergraduate basic pharmacology course  

British Library Electronic Table of Contents (United Kingdom)

The need to evolve with our ever-changing student bodies has never been as great as it is today, particularly given the advanced technological aptitude of today's students. This retrospective study evaluates student outcomes as they relate to overall course score and composite quiz and examination scores from a basic pharmacology course taught over three separate semesters using three different lecture delivery modalities: traditional in-class; blended; and online-only. A total of 48 students from a US university's health sciences bachelor degree programme enrolled in one of these three sections between 2009 and 2010. A one-way analysis of variance test with Tukey's honestly significant difference post hoc testing was utilized to determine if any statistical difference existed between the ...

2011-01-01

312

Flue-gas desulfurization inspection and performance evaluation. Manual  

Energy Technology Data Exchange (ETDEWEB)

The intent of this manual is to provide inspectors from Federal and state environmental agencies with information regarding the problems that plague lime/limestone slurry flue-gas desulfurization (FGD) systems that will aid them in their inspections and performance evaluations of these systems with respect to compliance with the emission standards that have evolved since the passage of the 1970 Clean Air Act. A unique feature of the manual is its structure as a tool, or working document, which will accompany the inspector on each plant inspection. Thus, the document is presented in user friendly fashion and tailored to provide practical information for its intended use--to assist in the systematic inspection of an FGD system to determine present and future compliance status. The approach entails the use of nomographs, checklists, matrices, simplified diagrams, cross-referencing, and indexing of textual information, and the presentation of important guidelines and ...

1985-10-01

313

FG Sge at the stage of dust shell ejection  

British Library Electronic Table of Contents (United Kingdom)

New photometric observations of the variable star FG Sge, a rapidly evolving planetary nebula nucleus, were performed in 2003?2008. On 230 nights, we obtained 86 UBV and 155 BV RI (or R c , I c ) magnitude estimates. The maximum amplitude of the V-band light variations was >8 m . Six deep minima and four high maxima were observed. Analysis of the light curve has shown that the pulsation period of the star remained constant since 1991 and was P = 115 days. We have studied the wavelength dependence of the extinction at various phases of the light curve. The blueing of the B-V color at deep minima is interpreted as the result of light scattering in the circumstellar dust shell of the star formed by preceding dust ejections since 1992. Our spectroscopic observations performed on nine nights in...

2009-01-01

314

Evolving Attachment Theory: Beyond Bowlby and Back to Darwin  

British Library Electronic Table of Contents (United Kingdom)

Abstract- In our reply to M. H. van IJzendoorn and M. J. Bakermans-Kranenburg (this issue) and R. A. Thompson (this issue), we highlight 2 challenges that attachment researchers face today: (a) closing the gap between the developmental and social psychological traditions and (b) connecting attachment theory to the broader field of evolutionary psychology. We contend that an evolutionary life history approach can contribute to both goals and argue that attachment researchers should consider moving beyond some of Bowlby's original formulations in order to permit further advancement of the field. Finally, we review van IJzendoorn and Bakermans-Kranenburg's criticism of the hypothesis that sex differences in attachment arise in middle childhood; we conclude that the claim that the hypothesis h...

2010-01-01

315

ENSO affects sex ratio progeny in captive Iberian red deer despite a steady feeding regime  

British Library Electronic Table of Contents (United Kingdom)

Climate variability greatly affects animals through direct and indirect effects. Animals with slow reproductive adaptation to ecological changes such as large mammals are likely to have evolved mechanisms to anticipate early such impacts of climate variability on the environment. One of the adaptive mechanisms between reproductive costs and benefits in mammals affects parental investment through biases in sex ratio. Deer might be likely to show an early detection of climate variability because conception takes place in early autumn, but the main raising cost in deer concerns lactation, which takes place at the end of the following spring. The aim of this paper is to assess whether there is a relationship between global indices of climate variability such as El Ni?o-Southern Oscillation (EN...

2011-01-01

316

Development of a Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System  

British Library Electronic Table of Contents (United Kingdom)

Understanding the processes responsible for coastal change is important for managing our coastal resources, both natural and economic. The current scientific understanding of coastal sediment transport and geology suggests that examining coastal processes at regional scales can lead to significant insight into how the coastal zone evolves. To better identify the significant processes affecting our coastlines and how those processes create coastal change we developed a Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System, which is comprised of the Model Coupling Toolkit to exchange data fields between the ocean model ROMS, the atmosphere model WRF, the wave model SWAN, and the sediment capabilities of the Community Sediment Transport Model. This formulation builds upon ...

2010-01-01

317

Determination of the biodegradation rate of asphalt for the Hanford grout vaults. Hanford Grout Technology Program  

Energy Technology Data Exchange (ETDEWEB)

Testing was initiated in March 1991 and completed in November 1992 to determine the rate at which asphalt is biodegraded by microorganisms native to the Hanford Site soils. The asphalt tested (AR-6000, US Oil, Tacoma, Washington) is to be used in the construction of a diffusion barrier for the Hanford grout vaults. Experiments to determine asphalt biodegradation rates were conducted using three separate test sets. These test sets were initiated in March 1991, January 1992, and June 1992 and ran for periods of 6 months, 11 months, and 6 months, respectively. The experimental method used was one originally developed by Bartha and Pramer (1965), and further refined by Bowerman et al. (1985), that determined the asphalt biodegradation rate through the measurement of carbon dioxide evolved.

1993-04-01

318

Darrieus vertical axis wind turbine program overview  

Science.gov (United States)

As a US Department of Energy (DOE) laboratory, Sandia Laboratories is developing Darrieus vertical axis wind turbine (VAWT) technology with the objective of encouraging private industry to produce economically feasible, commercially marketable wind energy systems. The first full cycle of development is essentially complete, and resulting current technology designs have been evaluated for cost-effectiveness. Aerodynamic, structural, and system analyses capabilities have evolved during this cycle to support and evaluate the system designs. This report presents some of the more salient recent developments, first generation costs, current activities, and future plans. Potential design improvements identified in the first development cycle are presented along with their cost benefits.

319

Corrosion and scale processes and their inhibition in simulated cooling water systems by monosaccharides derivatives  

British Library Electronic Table of Contents (United Kingdom)

A study of the ordinary mild steel/cooling water interface, with and without inhibitor, was carried out using electrochemical impedance spectroscopy (EIS). EIS spectra in uninhibited medium reveal that a layer of corrosion and scale products is formed naturally and evolves with the immersion time. Monosaccharides derivatives were used as corrosion inhibitors. Most of them exhibit good behaviour against corrosion of ordinary steel in simulated water systems. Their inhibiting efficiency increases with concentration rise and depends on molecular structure especially -OH groups' position on two adjacent carbons and their number. In addition, the effect of MoO4^2^- on the corrosion inhibition in the presence of the best inhibitor was also studied by EIS. The addition of MoO4^2^- enhanced the in...

2009-01-01

320

Continuous Paranematic-to-Nematic Ordering Transitions of Liquid Crystals in Tubular Silica Nanochannels  

CERN Document Server

The optical birefringence of rod-like nematogens (7CB, 8CB), imbibed in parallel silica channels with 10 nm diameter and 300 micrometer length, is measured and compared to the thermotropic bulk behavior. The orientational order of the confined liquid crystals, quantified by the uniaxial nematic ordering parameter, evolves continuously between paranematic and nematic states, in contrast to the discontinuous isotropic-to-nematic bulk phase transitions. A Landau-de Gennes model reveals that the strength of the orientational ordering fields, imposed by the silica walls, is beyond a critical threshold, that separates discontinuous from continuous paranematic-to-nematic behavior. Quenched disorder effects, attributable to wall irregularities, leave the transition temperatures affected only marginally, despite the strong ordering fields in the channels.

2008-01-01

321

Complexity of chaotic fields and standard model parameters  

CERN Document Server

In order to understand the parameters of the standard model of electroweak and strong interactions (coupling constants, masses, mixing angles) one needs to embed the standard model into some larger theory that accounts for the observed values. This means some additional sector is needed that fixes and stabilizes the values of the fundamental constants of nature. In these lecture notes we describe in nontechnical terms how such a sector can be constructed. Our additional sector is based on rapidly fluctuating scalar fields that, although completely deterministic, evolve in the strongest possible chaotic way and exhibit complex behaviour. These chaotic fields generate potentials for moduli fields, which ultimately fix the fundamental parameters. The chaotic dynamics can be physically interpreted in terms of vacuum fluctuations. These vacuum fluctuations are different from those of QED or QCD but coupled with the same moduli fields as QED and QCD are. The vacuum ...

2007-01-01

322

Comparison of interface evolution of ultrasonic aluminum and gold wire wedge bonds during thermal aging  

British Library Electronic Table of Contents (United Kingdom)

Ultrasonic gold and aluminum wire wedge bonding are widely used for electrical and signal interconnections of the integrated circuit chip packages. In this paper, based on the metallurgical theories and thermal aging test methods, the long-term thermal reliabilities of gold and aluminum wire wedge bonding on aluminum and Au/Ni/Cu pads, were investigated, respectively. At 200degreeC, the Au/Al bond interfaces evolved little when the storage time was less than 48h; with the aging time increasing, the interfacial intermetallic compounds (IMC) grew up from the pad (vertical growth); the primary compounds were Au5Al2 near the bond toe and heel, and Au2Al at the periphery. Then, the thickness of IMC was unchanged, and extended horizontally (lateral growth), Au5Al2 transformed into more stable Au...

2007-01-01

323

Collisionless driven reconnection in an open system  

Energy Technology Data Exchange (ETDEWEB)

Particle simulation studies of collisionless driven reconnection in an open system are presented. Collisionless reconnection evolves in two steps in accordance with the formation of two current layers, i.e., an ion current layer in the early ion phase and an electron current layer in the late electron phase. After the electron current layer is formed inside the ion current layer, the system relaxes gradually to a steady state when convergent plasma flow is driven by an external electric field with a narrow input window. On the other hand, when the convergent plasma flow is driven from the wide input window, magnetic reconnection takes place in an intermittent manner, due to the frequent formation of magnetic islands in the vicinity of neutral sheet. (author)

2000-06-01

324

Biodiversity, agriculture, and livelihoods: Co-evolution and competition in an Andean-Amazonian watershed  

Environmental Research Database

Objectives1. To create a strong, interdisciplinary evidence base about the relationships linking ecosystems, agrobiodiversity, wild biodiversity, and sustainable livelihoods, including the use of trade-off analysis (modeling the relationships between agricultural productivity, levels of biodiversity, and ecosystem resilience); crop evolutionary studies (wild relative/crop interactions) and socioeconomic, cultural, and nutritional studies of the contribution of biodiversity to different livelihoods asset [continued...]DescriptionAgriculture, ecosystems, and humans have co-evolved over millennia in the Andean-Amazonian region, creating the richest of all Vavilov centers of crop origin and diversity. The conservation of a wide range of domesticated crops and landraces (i.e., indigenous, ancestral varieties or cultivars that are distinct, uniform, and stable) and their co-evolution with crop wild relatives (CRW) has been essential for food security, adaptation to ...

2011-01-31

325

Airbags to Martian Landers: Analyses at Sandia National Laboratories  

Energy Technology Data Exchange (ETDEWEB)

A new direction for the national laboratories is to assist US business with research and development, primarily through cooperative research and development agreements (CRADAs). Technology transfer to the private sector has been very successful as over 200 CRADAs are in place at Sandia. Because of these cooperative efforts, technology has evolved into some new areas not commonly associated with the former mission of the national laboratories. An example of this is the analysis of fabric structures. Explicit analyses and expertise in constructing parachutes led to the development of a next generation automobile airbag; which led to the construction, testing, and analysis of the Jet Propulsion Laboratory Mars Environmental Survey Lander; and finally led to the development of CAD based custom garment designs using 3D scanned images of the human body. The structural analysis of these fabric structures is described as well as a more traditional example Sandia with the ...

1994-03-01

326

Abnormal structure or function of the amygdala is a common component of neurodevelopmental disorders  

British Library Electronic Table of Contents (United Kingdom)

The amygdala, perhaps more than any other brain region, has been implicated in numerous neuropsychiatric and neurodevelopmental disorders. It is part of a system initially evolved to detect dangers in the environment and modulate subsequent responses, which can profoundly influence human behavior. If its threshold is set too low, normally benign aspects of the environment are perceived as dangers, interactions are limited, and anxiety may arise. If set too high, risk taking increases and inappropriate sociality may occur. Given that many neurodevelopmental disorders involve too little or too much anxiety or too little of too much social interaction, it is not surprising that the amygdala has been implicated in many of them. In this chapter, we begin by providing a brief overview of the phy...

2011-01-01

327

A risk calculator for glyphosate resistance in Lolium rigidum (Gaud.)  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND: Glyphosate resistance has been confirmed in 58 populations of Lolium rigidum (Gaud.), a major weed of crops in southern Australia. Extensive use of glyphosate in conjunction with minimal soil disturbance has been identified as high risk for resistance to that herbicide. Land managers need a simple method for rapid assessment of the risk of resistance occurring as a result of past and proposed future management practices. Modelled on risk assessment nomographs, a simple calculator for indicating the risk of evolved glyphosate resistance in L. rigidum is described.RESULTS: The calculator uses the generations since first use and the frequency of use of glyphosate in combination with historical cultivation levels as critical factors for determining the risk of glyphosate resistance...

2008-01-01

328

A cosmological "probability event horizon" and its observational implications  

CERN Document Server

Suppose an astronomer is equipped with a device capable of detecting emissions -- whether they be electromagnetic, gravitational, or neutrino -- from transient sources distributed throughout the cosmos. Because of source rate density evolution and variation of cosmological volume elements, the sources first detected when the machine is switched on are likely to be ones in the high-redshift universe; as observation time increases, rarer, more local, events will be found. We characterize the observer's evolving record of events in terms of a "probability event horizon", converging on the observer from great distances at enormous speed, and illustrate it by simulating neutron star birth events distributed throughout the cosmos. As an initial application of the concept, we determine the approach of this horizon for gamma-ray bursts (GRBs) by fitting to redshift data. The event rates required to fit the model are consistent with the proposed link between core-collapse ...

2005-01-01

329

A comparison of the UHF Follow-On and MILSTAR satellite communication systems  

Science.gov (United States)

The author compares the UHF Follow-On and MILSTAR satellite communication systems. The comparison uses an analytical hierarchy process. Although the two systems have been tasked with different missions, a comparison of cost, capability, and orbit is conducted. UFO provides many of the same capabilities as MILSTAR, but on a smaller scale. Since UFO is also a new space system acquisition, it is used to compare dollars spent to field a viable communication system. A review of frequency bands, losses, and problems is conducted to establish the relationship. Cost data is provided to establish the major difference in the systems. While MILSTAR does possess more total capability than UFO, it is 10 times more costly. Additionally, UFO is a satellite that will evolve with new technology while MILSTAR is built to full capability immediately. In the author's opinion, the incremental performance of MILSTAR does not justify its incremental cost.

1991-09-01

330

A Late Holocene explosive mafic eruption of Villarrica volcano, Southern Andes: The Chaimilla deposit  

British Library Electronic Table of Contents (United Kingdom)

Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (<3.1ka) is one of the best exposed and widely dispersed pyroclastic deposits, related to both fall and flow activity. The deposit is dispersed over an area of 250km^2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phas...

2011-01-01

331

Waves in pulsar winds  

International Nuclear Information System (INIS)

The radio, optical, x-ray and gamma-ray nebulae that surround many pulsars are thought to arise from synchrotron and inverse Compton emission. The energy powering this emission as well as the magnetic fields and relativistic particles are supplied by a 'wind' driven by the central object. The inner parts of the wind can be described using the equations of MHD, but these break down in the outer parts, when the density of charge carriers drops below a critical value. This paper reviews the wave properties of the inner part (striped wind), and uses a relativistic two-fluid model (cold electrons and positrons) to re-examine the nonlinear electromagnetic modes that propagate in the outer parts. It is shown that in a radial wind, two solutions exist for circularly polarized electromagnetic modes. At large distances one of them turns into a freely expanding flow containing a vacuum wave, whereas the other decelerates, corresponding to a confined flow.

2010-12-01

332

The segmental gastrocnemius muscles' flap: A cadaveric study  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to evaluate the feasibility of splitting each head of the gastrocnemius muscle into two segments. This prospective study was conducted on 35 fresh cadavers with injection of radio-opaque contrast material in the popliteal artery. Seventy medial gastrocnemius and 70 lateral gastrocnemius muscle specimens were obtained. Gastrocnemius intramuscular arterial anatomy was analysed by using the digital X-ray technique. The most common vascular pattern found in this study was both bellies supplied by individual sural arteries, which shows distal bifurcation. The medial sural artery always showed bifurcation in the medial gastrocnemius muscle in both lower limbs, whereas this bifurcation of the lateral sural artery was present in only 87% cases and 13% of cases showed a si...

2011-01-01

333

The content of L-carnitine in meat after different methods of heat treatment  

British Library Electronic Table of Contents (United Kingdom)

Purpose - The objective of this study is to examine the effects of pan-frying, boiling and cooking in a microwave on the amount of L-carnitine in meat and to look at its distribution in the surrounding fluid after food processing. Design/methodology/approach - Total carnitine, free carnitine and acylcarnitines were determined in meat samples from beef, pork and poultry (including ostrich) and in a liver sample from beef. The measurements were carried out before and after the specimens were subjected to different heat treatments. A radio-enzymatic assay was used for measurement of L-carnitine. Results are expressed per 100 gram dry matter and per 100 gram wet weight. Findings - Except for pan-frying, virtually no losses of carnitine occurred during the different procedures of heat treatment...

2011-01-01

334

Temperature problems in mine rescue  

Energy Technology Data Exchange (ETDEWEB)

Describes temperature and humidity sensing devices used in mine rescue operations. Chemical indicators use chemical substances that melt at predetermined temperatures and display the actual temperature in the range of 40-50 C. Electronic temperature monitoring devices release acoustic signals as soon as a temperature of 40 or 45 C has been exceeded. A more recent piece of equipment combines the ULR rescue communication set with remote temperature sensing. A digital meter that measures temperature and humidity in the range of -100 to +200 C and 3 to 98% respectively has also been developed. The Central Mine Rescue Station in Bytom, Poland has developed equipment that permits body temperature and pulse rate of a rescuer to be measured and transmitted by radio over a distance of up to 50 m. Safe threshold values can be set for each individual rescuer.

1990-08-01

335

Synthesis and biodistribution of "9"9"mTc-peptides conjugated adenine as tumor imaging agents  

International Nuclear Information System (INIS)

Two peptide ligands conjugated adenine, [9-N-(tritylmercapto acetyl diglycyl aminoethyl) adenine, Tr-MAG_2-Ade] and [9-N-(tritylmercapto acetyl triglycyl aminoethyl) adenine, Tr-MAG3-Ade], are synthesized and labeled with "9"9"mTc by directly labeling method. The stability of "9"9"mTc-MAG_2- adenine and "9"9"mTc-MAG_3-adenine in vitro is measured. The uptake radios of tumor to muscle at 3h post-injection are 5.70 and 4.92, respectively. The biodistribution and scintigraphic imaging studies show that the two complexes have high localization in tumor and high contrasted tumor images can be obtained, which suggest their potential utility as tumor imaging agents. But the high radioactivity of abdomen could prevent the tumor imaging in this area. (author)

2007-07-01

336

Seasonal variation measurements of radon levels in caves using SSNTD method  

Energy Technology Data Exchange (ETDEWEB)

The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm{sup -3}, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves.

2008-08-15

337

Seasonal variation measurements of radon levels in caves using SSNTD method  

International Nuclear Information System (INIS)

The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm-3, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves.

2008-08-01

338

Search for tachyons associated with EAS at energies E>=3x10"1"6eV  

International Nuclear Information System (INIS)

This paper describes an experiment which has been performed with a somewhat different philosophy in its approach as compared to previous work. (a) The trigger threshold energy was increased by more than a factor of ten on previous experiments reducing the dilution effect of many lower energy showers known not to produce tachyons. 1673 shower were recorded. (b) The exposure time was made longer than previous experiments in order to obtain a reasonably large statistical sample at the higher threshold. Observations were made between February 1979 and June 1980, the total live time being 9768 hours. (c) Records of the detector output amplitude for the 480#mu#s lead time were integrated point by point as is sometimes done in radio astronomy, this gives the integrated energy deposition within the detector.

339

Satisfying story of how it all began  

Energy Technology Data Exchange (ETDEWEB)

{sup N}ow this 'Big Bang' idea seemed to me to be unsatisfactory...for it is an irrational process that cannot be described in scientific terms.' With this rather derisory remark (or at least so intended) in a 1950 radio broadcast, Fred Hoyle named the theory that rivalled his steady-state theory. The Big Bang has subsequently become the dominant paradigm in attempts to understand our universe. It is also one of the dominant ways in which popular-science writing seeks to persuade people to part with their cash. Simon Singh has rapidly made a name for himself as one of the leading popularizers of science, with his previous books Fermat's Last Theorem and The Code Book bringing accessible science to a wide audience . Big Bang brings him to a much busier marketplace, where he must compete both with other science writers and with working scientists. (U.K.)

2004-12-01

340

Recent advances in silicon-germanium alloy technology and an assessment of the problems of building the modules for a radioisotope thermoelectric generator  

International Nuclear Information System (INIS)

This paper reviews the state of the art of silicon-germanium technology and assesses the problems of building thermoelectric modules in Europe, based upon silicon-germanium alloys, for use in multihundred watt radio-isotope thermoelectric generator. The generator developed in the United States for the International Solar Polar mission has been used as a reference system. The essential features of an alternative system, which employs thermocouples fabricated from improved silicon-germanium alloys based upon a design by the Fairchild Space and Electronics Company, is also described. It is concluded that although the fabrication of reliable electrical contacts will present a major problem, the technology is available in Europe to build thermoelectric modules similar to those developed for the International Solar Polar mission. (orig.).

341

Radio cellular phones and health: Up-to-date research on human health; Radiotelephones cellulaires et sante: mise au point des recherches portant sur la sante chez l'homme  

Energy Technology Data Exchange (ETDEWEB)

Cellular telephones emit a radiofrequency electromagnetic field, part of which is absorbed in the user's head. Many studies have been conducted to look for their possible health hazard to human, at the experimental, epidemiological or clinical level. After a short recall on dosimetry, the author describes the state-of-the art about harmful and irreversible effects, up to now not confirmed, and about some benign symptoms which look absolutely actual. A causal relationship of the electromagnetic field on these benign symptoms is however not proven; other, studies are running to evaluate their possible long-term consequences. Interferences with cardiac pacemakers can easily be avoided by holding the telephone handset farther than 10 cm. (author)

1999-12-01

342

Radiation therapy and Ewing's sarcoma in childhood  

International Nuclear Information System (INIS)

Despite high local control rate in Ewing's sarcoma the exact indication of radiation therapy is still controversial as well as the choice of the target volume and the optimal dose of radiation. The importance of the quality of radiotherapy has been stressed in recently published data and has shown a significant impact on long term local control with adequate radiation therapy. The dramatic improvement of precision allowed by the conformal therapy and three dimensional dosimetry allow to expect a decrease of late effects expected for second malignancies. However, late sequelae and radio-induced osteosarcoma still remain the major side effects after radiotherapy. The authors discuss the results of the main trials on Ewing's sarcoma on the choice of dose and target volume. Surgery is still the preferred choice for small tumors if the foreseen outcome is identical. (authors). 28 refs.

343

RXTE observations of Cas A  

International Nuclear Information System (INIS)

Rossi X-ray Timing Explorer (RXTE) observations of the bright supernova remnant Cas A have revealed a hard power law component above 10 keV in addition to two thermal components inferred from ASCA measurements of the many line centroids from low-Z elements. The power law can be shown to be consistent with synchrotron emission from radio to hard x-rays by electrons of up to 4 x 10"1"3 eV. Measurement of the 1157 keV line by CGRO from "4"4Sc in the chain of decay of "4"4Ti predicts that the two "4"4Ti lines at 68 and 78 keV should appear at the CGRO intensity. RXTE has placed upper limits on such lines that are marginally consistent with the CGRO measurement. Implications of these results on sites for cosmic ray acceleration and nucleosynthesis are discussed.

1999-01-01

344

Quantification of the thrombogenicity of Dacron aortic prostheses  

International Nuclear Information System (INIS)

Eight patients with double-velour Dacron aorto-femoral grafts implanted for 2-60 months were studied. Indium-111-labelled platelets were found to have a shortened mean platelet lifespan (MPLS) of 138 +- 32 hours compared with the normal platelet lifespan of 224 +- 23 hours. Labelled platelets accumulated on all grafts, irrespective of graft age, to a maximum of 1,80 +- 0,83% of whole body radioactivity; thereafter graft radio-activity decreased. This suggests that platelets on the graft are in dynamic equilibrium with those in the circulation. Platelets may be lost from the graft by embolization or radioactivity may be released because of platelet lysis. Although MPLS may depend on the age and surface area of the graft, concomitant arterial disease probably also contributes to the shortened MPLS.

345

Present status of free electron laser and its utilization research facilities  

International Nuclear Information System (INIS)

The historical back ground of free electron laser (FEL) and the present status of development and utilization research of FEL facilities in the world are explained. Eight facilities such as Stanford Univ., UCSB, Duke Univ., Vanderbilt Univ., LANL AFEL (USA), FOM FELIX (Netherlands), N-lands LURE CLIO (France) and FELI (Japan) can be used. The principle of FEL generation process is that free electrons move in a zigzag direction to generate radio waves which interfere with each other to become monochromatic light and then free electron laser. The benefits of FEL, quality of electron beam, limit of wave length of FEL, problems and development of utilization technologies of FEL are explained. (S.Y.)

1997-11-01

346

Preparation and dosimetry of radiotherapeutic particles for arthropaties; Preparacion y dosimetria de particulas radioterapeuticas para artropatias  

Energy Technology Data Exchange (ETDEWEB)

It was developed a new formulation of macro aggregates of Samarium 153 ({sup 153} Sm-MH) for the arthropaties treatment. The radio pharmaceutic was prepared by reaction of Samarium 153 chloride (SmCl{sub 3}) in aqueous environment with sodium boron hydride in NaOH 0.5 N. The microscopic analysis shown that the particles have an average size of 4% m (range 1-14 {mu} m). The velocity of sedimentation was 0.008 cm/min with high stability in vitro in human serum. The biological studies in healthy rabbits, shown that the complex is retained inside the articulation still eight days after of the administration of the radiopharmaceutical. Likewise, it is presented the data of absorbed dose in the different target organs, which was determined by thermoluminescent dosimetry (TLD) through the use of a REMCAL phantom (radiation equivalent manikin calibration). (Author)

1999-07-01

347

Premature Failure of a Riata Defibrillator Lead Without Impedance Change or Inappropriate Sensing: A Case Report and Review of the Literature  

British Library Electronic Table of Contents (United Kingdom)

Premature Failure of a Riata Defibrillator Lead. A 63-year-old woman with a St. Jude Medical Riata 1570 right ventricular lead complained of intermittent hiccups 2 months after implant. Interrogation revealed elevated pacing threshold and diaphragmatic stimulation. Pacing and shock lead impedances remained stable. No inappropriate sensing was noted. Fluoroscopic examination of the lead revealed a thin radio-opaque wire seen between the 2 defibrillator coils away from the main body of the lead. After extraction, a tear in the insulation of the lead was noted allowing the inner wire to protrude. This case illustrates a novel mechanism of insulation failure without inappropriate sensing or impedance change.-(J Cardiovasc Electrophysiol, Vol. 22, pp. 1070-1072, September 2011)

2011-01-01

348

Opportunistic Cooperation in Cognitive Femtocell Networks  

CERN Document Server

We investigate opportunistic cooperation between unlicensed secondary users and legacy primary users in a cognitive radio network. Specifically, we consider a model of a cognitive network where a secondary user can cooperatively transmit with the primary user in order to improve the latter's effective transmission rate. In return, the secondary user gets more opportunities for transmitting its own data when the primary user is idle. This kind of interaction between the primary and secondary users is different from the traditional dynamic spectrum access model in which the secondary users try to avoid interfering with the primary users while seeking transmission opportunities on vacant primary channels. In our model, the secondary users need to balance the desire to cooperate more (to create more transmission opportunities) with the need for maintaining sufficient energy levels for their own transmissions. Such a model is applicable in the emerging area of cognitive ...

2011-01-01

349

Nigeria's radioactive waste management policy and strategy document  

International Nuclear Information System (INIS)

Radioactive waste for legal and regulatory purposes may be defined as material that contains or is contaminated with radio-nuclides at concentrations or activities greater than clearance levels as established by the regulatory body, and for which no use is foreseen. Safe management of radioactive waste is essential to ensure protection of humans and environment. Radioactive waste management policy is a guideline for the safe management of radioactive waste. It expresses the commitment of the country towards the goal. Government should initiate investigation into best long-term option for management of spent nuclear fuels. Process of selecting option and eventual site should involve comprehensive public participation within set time frames (with deep geological disposal as preferred management option).

2009-07-14

350

Neutron star evolution and emission  

Science.gov (United States)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The authors investigated the evolution and radiation characteristics of individual neutron stars and stellar systems. The work concentrated on phenomena where new techniques and observations are dramatically enlarging the understanding of stellar phenomena. Part of this project was a study of x-ray and gamma-ray emission from neutron stars and other compact objects. This effort included calculating the thermal x-ray emission from young neutron stars, deriving the radio and gamma-ray emission from active pulsars and modeling intense gamma-ray bursts in distant galaxies. They also measured periodic optical and infrared fluctuations from rotating neutron stars and search for high-energy TeV gamma rays from discrete celestial sources.

1997-08-01

351

Measurements to be taken after a nuclear accident in order to limit the uptake of radionuclides from the soil by nutrition crops  

International Nuclear Information System (INIS)

By the department Radio-ecology of the Laboratory for Radiation Research, in the period 1981 up to 1989 inclusive, the transfer has been studied, from soil to plant, of a number of important activation and fission products, originating in the nuclear-power production in nuclear power plants. The purpose of this study was twofold: on the one side the quantification of this transfer for various agrarian systems and on the other side to find out in how far, after an accidental contamination, certain agriculture activities can influence essentially the transfer and subsequently the radiation burden for the population. Emphasis lay, the last years, in particular upon this second aspect. The results of this study form essential basic data for diffusion models for radioactive materials which, in turn, are important in estimating the effects of measures. (author). 6 refs.; 4 figs.

352

Magnetic layer formation on plasma nitrided CoCrMo alloy  

British Library Electronic Table of Contents (United Kingdom)

In this study structural and magnetic character of the expanded austenite phase (gN) layer formed on a medical grade CoCrMo alloy by a low-pressure Radio-Frequency plasma nitriding process was investigated. The formation of the expanded austenite phase is facilitated at a substrate temperature near 400^oC for 1, 2, 4, 6 and 20h under a gas mixture of 60% N2-40% H2. The magnetic state of the gN layers was determined by a surface sensitive technique, magneto-optic Kerr effect (MOKE), and with a scanning probe microscope in magnetic force mode (MFM). Strong evidence for the ferromagnetic nature of the gN-(Co,Cr,Mo) phase is provided by the observation of stripe domain structures and the hysteresis loops. The ferromagnetic state for the gN phase observed here is mainly linked to large lattice ...

2011-01-01

353

Irradiation of human insulin in aqueous solution, first step towards radiosterilization  

British Library Electronic Table of Contents (United Kingdom)

The degradation of irradiated human insulin in aqueous solutions was investigated in order to protect the protein against ionizing radiation. The influence of the drug concentration, excipients and irradiation temperature were studied.Aqueous solutions at pH 2 were irradiated by gamma rays or by accelerated electrons. Two different high-performance liquid chromatography (HPLC) methods were used: reverse-phase high-performance liquid chromatography (RP-HPLC)/UV and size exclusion liquid chromatography (SEC/UV) to investigate both the fragmentation and the formation of higher molecular weight proteins.In solution without excipients irradiated at ambient temperature at 10kGy, the loss of human insulin is almost complete. Addition of radio-protecting excipients (free radicals scavengers) and c...

2007-01-01

354

Investigation of methods for improving models of ionospheric plasma-density irregularities and radio-frequency scintillation. Technical report  

Energy Technology Data Exchange (ETDEWEB)

Many modern military systems used for communications, command and control, navigation, and surveillance depend on reliable and relatively noise-free transmission of radiowave signals through the earth's ionosphere. Small-scale irregularities in the ionospheric density can cause severe distortion, known as radiowave scintillation, of both the amplitude and phase of these signals. The WBMOD computer program can be used to estimate these effects on a wide range of systems. The objective of this study is to investigate improvements to the WBMOD model based on extensive data sets covering both the equatorial and high-latitude regimes. This report summarizes the work completed during the second year, which include completion of the new models for the equatorial region and initial development of models for the high latitude (auroral and polar cap) region.

1993-11-01

355

Interpolating atmospheric water vapor delay by incorporating terrain elevation information  

British Library Electronic Table of Contents (United Kingdom)

In radio signal-based observing systems, such as Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR), the water vapor in the atmosphere will cause delays during the signal transmission. Such delays vary significantly with terrain elevation. In the case when atmospheric delays are to be eliminated from the measured raw signals, spatial interpolators may be needed. By taking advantage of available terrain elevation information during spatial interpolation process, the accuracy of the atmospheric delay mapping can be considerably improved. This paper first reviews three elevation-dependent water vapor interpolation models, i.e., the Best Linear Unbiased Estimator in combination with the water vapor Height Scaling Model (BLUE?+?HSM), the Best Linear Unbiased Es...

2011-01-01

356

Follow-up and diagnosis of recurrences after radio-chemotherapy of malignant head and neck tumors  

International Nuclear Information System (INIS)

339 CT und 95 MRT examinations in 210 partients were evaluated retrospectively to determine the value of CT and MRT for follow-up of head and neck tumors and for diagnosing recurrences. Semi-quantitative evaluation of tumor extent during and after radiotherapy showed advantages for MRT since changes induced by treatment, particularly oedema, produced less contrast loss in the images. CT had a sensitivity of 81% for the recognition of recurrences; this was 92% for MRT. Specificity for CT was 76% and for MRT 86%. Concerning the reliability of individual diagnostic criteria, space occupying lesions were the most valuable in CT diagnosis. For MRT, space occupying lesions and infiltration into neighbouring structures were of equal value. Because of differences in the nature of the signals, MRT proved better than CT in characterising recurrent masses and this improved the differentiation between scarring and local tumour recurrence. (orig.).

357

Fast Beam Intensity Measurements for the LHC  

CERN Document Server

Particle accelerators are constructed and operated for a wide variety of applications. In particle physics - the branch of physics that studies the elementary constituents of matter and forces between them - high energy accelerators are used to look deep into the structure of matter. Medical particle accelerators are used for example in medicine to treat tumours [31], in imaging techniques such as Positron Emission Tomography (PET) [24], or for the radio-isotopes production. They also serve in many other industrial branches, e.g. geology, radiocarbon dating [39], molecular complex spectroscopy, lithography, food preservation etc. The eld of accelerator technology draws knowledge and expertise from a wide range of scientic disciplines and uses the latest technical knowledge. The incomplete list of covered disciplines includes mathematics, physics, electronics, computing, electromagnetic eld technology, microwave technology, cryogenics, vacuum technology, special ...

2010-01-01

358

Explosives detector  

Energy Technology Data Exchange (ETDEWEB)

An apparatus for non-invasively inspecting an object, such as an item of luggage, for explosives material is described. It comprises a multi-channel thermal neutron inspection system having a plurality of neutron irradiation chambers. Simultaneous operation of several channels increases the maximum system throughput several times. Each chamber has a lithium neutron source which is stimulated to neutron production by a proton beam. Beam switching magnets are energised by pulsing to divert a common proton beam to each source in turn. The initial beam is generated by a radio frequency quadrupole accelerator. The advantages of this system are very low residual source activity and controllable neutron production thereby minimising safety hazards. The irradiation chamber may contain several different gamma ray detectors to identify the elements present in explosives material. In addition, a neutron radiography imaging means may be employed to identify the presence of ...

1991-10-02

359

Effects of sputtering pressure on the characteristics of lithium ion conductive lithium phosphorous oxynitride thin film  

British Library Electronic Table of Contents (United Kingdom)

Lithium phosphorous oxynitride(Lipon) thin films as a lithium ion conductive electrolyte were prepared by radio frequency reactive sputtering in N2 plasma. The properties of the amorphous Lipon solid electrolyte were investigated as a function of N2 pressure during reactive sputtering. The ionic conductivity and the electrochemical stability of Lipon thin films improved drastically as the N2 pressure decreased. The ionic conductivity closed to 10?6 S cm?1 and obtained a stability window of 1.0?5.0 V with an N2 pressure of 5 mTorr, where the number of nitrogen bonds between the phosphate groups were more than those formed at higher pressure. It was possible to fabricate the Li//LiCoO2 complete thin film battery using this Lipon solid electrolyte, which exhibited excellent discharge characte...

2006-01-01

360

Beam Profile Measurement and its Application to Calculate Beam Emittance Using Wire Scanner for the PEFP 20MeV linac  

International Nuclear Information System (INIS)

A 20-MeV proton accelerator is developed by Proton Engineering Frontier Project (PEFP) at Korea Atomic Energy Research Institute (KAERI). The 20MeV accelerator consists of 50keV proton injector, 3MeV RFQ (Radio frequency Quadrupole), 20MeV DTL (Drift Tube Linac) and 20MeV beam line. The beam profile was measured at the end of the 20MeV beam line with wire scanner. Moreover the beam emittance was calculated from the quad scan method using beam line quadrupole magnets. In this paper, the beam profile measurement results are presented and the emittance measurement from the quad scan method is discussed

2010-10-01

361

Analysis by radio-gaschromatography of volatile aldehydes produced by the linoleic acid oxidation of soya- and oats-lipoxygenase  

International Nuclear Information System (INIS)

Soya- and oats-lipoxygenase (E.C. 1.13.1.13) are incubated by "1"4C-marked linoleic acid. The volatile aldehydes arising thereby are isolated. The activity of the components separated by gaschromatography is written down by a printing indicator and the impulses/min are registered and printed out by a ratemeter. Thus the aldehydes which are produced by the enzymatic oxydation with lipoxygenase from the molecule of the linoleic acid can be determined. The composition of the mixture of aldehydes is calculated in mol-% from the measured impulses for peak. A possible origin of pathway is indicated for the main reaction products hexanal (soyalipoxygenase) and non-trans-2-enal (oats-lipoxygenase). (orig.).

362

A study on the real-time radiation dosimetry measurement system based on optically stimulated luminescence  

International Nuclear Information System (INIS)

The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity. Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-access and hazardous. In addition, optical fiber dosimeters are immune to electrical and radio-frequency interference. In this paper, a novel remote optical fiber radiation dosimeter is described. The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL. The measuring range of the dosimeter is from 0.1 to 100 Gy. The equipment is relatively simple and small in size, and has low power consumption. This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions. (authors)

2008-05-01

363

A study on rf plasma nitriding at a constant power in different H_2-N_2 mixtures at different temperatures  

International Nuclear Information System (INIS)

Austenitic stainless steel AISI 304 has been nitrided by radio frequency (rf) plasma containing various nitrogen-hydrogen gas mixtures, in order to study the effect of hydrogen on structure and magnetic properties of the formed compound layer. The thermal temperature has been measured at the vicinity of the samples. The compound layer thus produced has been characterized using, X-ray diffractometer and vibration sample magnetometer. Providing the total pressure of nitrogen and hydrogen is held constant, the addition of hydrogen up to 50% gives new structural phases. The magnetization values of the plasma treated samples are strongly dependent on the percentage of H_2 in the gas phase. An excessive amount of hydrogen (#approx#75%) on the other hand, retards the nitriding process. The surface temperature of the sample and plasma condition is crucial factors for nitriding process.

2006-04-15

364

A radiation monitoring system for nuclear fusion devices  

International Nuclear Information System (INIS)

Fusion device produces high-level neutrons and #gamma#-rays, which would hazard the safety of the public and workers if the doses would be higher than the regulatory limits because of leakage from the bio-shielding and skyshine. It is essential to monitor the radiation doses in the workshop and the enumerative around fusion devices. A radiation monitoring system (RMS) for full (near and far) areas around a nuclear fusion device has been designed and developed, which can achieve the monitoring and controlling of radiation doses in the workshop area by using the Controller Area Network (CAN), in the institution area by using the Bluetooth Ad hoc network based on a new tree topology formation and routing protocol and in a long range environment by using the General Packet Radio Service (GPRS) network. (authors)

2005-12-01

365

A proposed linac cavity rf drive system for the Los Alamos extreme ultraviolet free-electron laser  

Energy Technology Data Exchange (ETDEWEB)

Since 1979, scientists and engineers at the Los Alamos National Laboratory have designed, constructed, and operated a radio-frequency (RF) linac free-electron laser (FEL) at wavelengths from 9 to 45 /mu/m. Coupled with success of other research centers investigating wavelengths from the visible to far-infrared, Los Alamos is now proposing a vacuum-ultraviolet and soft x-ray (referred to henceforth as extreme ultraviolet, (XUV)) FEL oscillator/Self-Amplified Spontaneous Emission amplifier with beam energies ranging from 100 MeV to 1 GeV. This paper will focus on the first milestone of the proposed Los Alamos XUV project, i.e., a 250-MeV linac with approximately 50 mA of average current, producing photons with wavelengths below 1000 /angstrom/. 3 refs., 3 figs.

1989-01-01

366

A program for passively tracking a target using an array of sensors  

Energy Technology Data Exchange (ETDEWEB)

The problem of passively tracking a moving signal source has importance in a variety of applications such as radar, sonar, seismology, and radio astronomy. In many applications, only limited information is available about the signal source. It will be assumed here that only the signals which are detected by the sensors and the velocity of the source signal are known. The objective of this document is to present a program which passively tracks a target using an array of sensors. This program is available in MATLAB, version 3.5. The algorithm which is implemented consists of three main parts: time delay estimation, passive localization, and data post processing. Each of these parts are discussed, and the mathematical foundation for their solution given. Following, this the organization of the program is presented, and an example of its usage is given.

1993-01-01

367

A nanosized silicon thin film as high capacity anode material for Li-ion rechargeable batteries  

Energy Technology Data Exchange (ETDEWEB)

Silicon thin film with thickness in range 1000-5300 A deposited on rough Cu foil by a radio frequency magnetron sputtering is used as anode materials for Li-ion rechargeable batteries. The SEM, XRD and TEM analysis reveals that the Si thin film has a floccular nano-sized multi-crystalline structure. Li ions insertion/extraction evaluation is performed mainly with constant current charge/discharge cycling and cyclic voltammetry (CV) at room temperature. The cycleability and reversible discharge capacity are found to depend on the film thickness, and thinner films give larger accommodation capacity. A 3120 A Si film provides a reversible specific capacity over 3500 mA hg{sup -1} with excellent cycleability under 0.5 C charge/discharge rate.

2006-07-15

368

X-ray and vibrational spectroscopy of manganese complexes relevant to the oxygen-evolving complex of photosynthesis  

Energy Technology Data Exchange (ETDEWEB)

Manganese model complexes, relevant to the oxygen-evolving complex (OEC) in photosynthesis, were studied with Mn K-edge X-ray absorption near-edge spectroscopy (XANES), Mn Kb X-ray emission spectroscopy (XES), and vibrational spectroscopy. A more detailed understanding was obtained of the influence of nuclearity, overall structure, oxidation state, and ligand environment of the Mn atoms on the spectra from these methods. This refined understanding is necessary for improving the interpretation of spectra of the OEC. Mn XANES and Kb XES were used to study a di-(mu)-oxo and a mono-(mu)-oxo di-nuclear Mn compound in the (III,III), (III,IV), and (IV,IV) oxidation states. XANES spectra show energy shifts of 0.8 - 2.2 eV for 1-electron oxidation-state changes and 0.4 - 1.8 eV for ligand-environment changes. The shifts observed for Mn XES spectra were approximately 0.21 eV for oxidation state-changes and only approximately 0.04 eV for ligand-environment changes. This ...

2001-05-16

369

Investigating the formation mechanism of soot-like materials present in blast furnace coke samples  

Science.gov (United States)

An attempt to gain an understanding of the formation mechanism of these 'soot-like' materials has been made by means of tracing the changes in the molecular-mass distribution and molecular structure of the NMP-extractable materials from an injectant coal as well as its partially gasified chars and its pyrolytic tars. Variations in the SEC chromatograms provide clues about changes in the apparent molecular-mass distributions of these NMP extracts. Results suggest that the build-up of 'soot-like' materials follows from the secondary reactions of tars evolved from the injectant coal. The likely secondary-reaction pathways have been probed by collating structural information on these NMP extracts. The time-resolved 13-16 and 22-25 min elution fractions from the SEC column have been characterized using UV fluorescence (UV F) spectroscopy. Greater concentrations of larger aromatic ring systems are found present in samples formed under ...

2008-09-15

370

Gas evolution in aluminum electrolytic capacitors  

Science.gov (United States)

Gas evolution in aluminum electrolytic capacitors constitutes one of their main drawbacks in comparison to other types of capacitors lacking a liquid electrolyte. In this respect, one of the most common causes of failure shown by liquid electrolyte capacitors is electrolyte leakage through the seal or even explosions produced by internal pressure buildup. In order to prevent these hazards, some substances, known as depolarizers, are usually added to the capacitor electrolyte with the purpose of absorbing the hydrogen evolved at the cathode (1, 2). Although the gas evolution problem in electrolytic capacitors has been known for a long time, there is a lack of literature on both direct measurements of the gas evolved and assessments of the amount of depolarizer active for the hydrogen absorption process. Aluminum electrolytic capacitors of 100..mu..F and 40V nominal voltage, miniature type (diam 8 mm, height 18.5 mm), were manufactured under ...

1984-03-01

371

Coal deposits in the front ranges and foothills of the Canadian Rocky Mountains, southern Canadian Cordillera  

Energy Technology Data Exchange (ETDEWEB)

Over one-third of Canada's coal resources occurs in the southern Canadian Rocky Mountains, with major deposits in the Front Ranges, Inner Foothills and Outer Foothills. In the Front Ranges, deposits of metallurgical and thermal, high-volatile bituminous to semi-anthracite coal occur in the Late Jurassic-Early Cretaceous Mist Mountain Formation. In the Inner Foothills of northeastern British Columbia and west-central Alberta, resources of metallurgical and thermal medium- and low-volatile bituminous coal occur in Early Cretaceous strata of the Gething and Gates Formations. In the Outer Foothills resources of thermal, high-volatile bituminous coal occur in Late Cretaceous and Paleocene strata of the Belly River Coalspur and Paskapoo Formations. The major deposits of the Front Ranges and Inner Foothills accumulated within the coastal plains of the Fernie and Moosebar-Clearwater seas. Shorelines prograded to the north and northeast into a foreland basin that ...

1993-09-01

372

Transluminal radio-frequency thermal ablation using a stent-type electrode: an experimental study  

Energy Technology Data Exchange (ETDEWEB)

To assess the feasibility of transluminal radiofrequency thermal ablation using a stent-type electrode and to determine, by means of in-vivo and in-vivo animal studies, the appropriate parameters. In-vivo: the radiofrequency electrode used was a self-expandable nitinol stent with 1cm insulated ends. A stent was placed in the portal vein of bovine liver, and ablations at target temperatures of 70, 80, 90, and 100 .deg. C were performed. Ablated sizes were measured longitudinally. In vivo: four mongrel dogs were anesthetized, and a stent was inserted in the common bile duct under fluoroscopic guidance through an ultrasound-guided gall bladder puncture site. The ablation temperature was set at 80 .deg. C, and each dog underwent proximal and distal esophageal ablations lasting 12 minutes. They were sacrificed immediately. In-vivo: ablated sizes showed significant correlation with target temperatures (r>0.04; p<0.05). Although most lesions were fusiform, dumbbell-shaped ...

2003-06-01

373

Simulation and Observation of Acoustic-Gravity Waves in the Ionosphere  

Science.gov (United States)

Atmospheric and ionospheric perturbations associated with the acoustic-gravity waves (AGW) with typical frequencies of a few hertz -millihertz are considered. These events may be caused by the influence from space and atmosphere as well as by oscillations of the Earth surface and other near-surface phenomena. The surface sources include long-period oscillations of the Earth's surface, earthquakes, explosions, thermal heating, seisches and tsunami waves. The wavelike phenomena manifest themself as travelling disturbances of air (in the atmosphere) and of electron density (in the ionosphere). Travelling ionospheric disturbances (TIDs) are well detected by radio physical methods. AGW generation by near-surface sources is modeled by the numerical solution of the equation of geophysical fluid dynamics for different sources in two-dimensional non-linear dissipative compressible atmosphere. The numerical calculations are based on the FCT (Flux Corrected Transport) ...

2010-01-01

374

Gamma-ray pulse height spectrum analysis on systems with multiple Ge detectors using a spectrum summing  

Energy Technology Data Exchange (ETDEWEB)

A technique has been developed at the Idaho National Engineering Laboratory to sum high resolution gamma-ray pulse spectra from systems with multiple Ge detectors. Lockheed Martin Idaho Technologies Company operates a multi-detector spectrometer configuration at the Stored Waste Examination Pilot Plant facility which is used to characterize the radio nuclide contents in waste drums destined for shipment to Waste Isolation Pilot Plant. This summing technique was developed to increase the sensitivity of the system, reduce the count times required to properly quantify the radionuclides and provide a more consistent methodology for combining data collected from multiple detectors. In spectrometer systems with multiple detectors looking at non homogenous waste forms it is often difficult to combine individual spectrum analysis results from each detector to obtain a meaningful result for the total waste container. This is particularly true when the counting statistics in ...

1997-05-01

375

17- and 24-GHz observations of southern pulsars  

Science.gov (United States)

We present observations of PSRs J0437-4715, J0738-4042, J0835-4510, J0908-4913, J1048-5832, J1622-4950, J1644-4559, J1721-3532 and J1740-3015 at 17 GHz using the Parkes radio telescope. All nine were detected at 17 GHz, additionally, we detected PSR J0835-4510 and J1622-4950 at 24 GHz. Polarization profiles of each pulsar and the variation with frequency are discussed. In general, we find that the highly polarized edge components of young pulsars continue to dominate their profiles at 17 GHz. Older pulsars (?105 yr) appear to be almost completely depolarized. Our detection of PSR J0437-4715 is the highest frequency observation of a millisecond pulsar to date, and implies a luminosity at 17 GHz of 14 ?Jy kpc2, and a mean spectral index of 2.2. We find that the spectral index of the magnetar PSR J1622-4950 is flat between 1.4 and 24 GHz, similar to the other known radio magnetars XTE J1810-197 and 1E 1547.0-5408. The profile is similar to that ...

2011-06-01

376

[Fe]-hydrogenases in green algae: photo-fermentation and hydrogen evolution under sulfur deprivation  

Energy Technology Data Exchange (ETDEWEB)

Recent studies indicate that [Fe]-hydrogenases and H{sub 2} metabolism are widely distributed among green algae. The enzymes are simple structured and catalyze H{sub 2} evolution with similar rates than the more complex [Fe]-hydrogenases from bacteria. Different green algal species developed diverse strategies to survive under sulfur deprivation. Chlamydomonas reinhardtii evolves large quantities of hydrogen gas in the absence of sulfur. In a sealed culture of C. reinhardtii, the photosynthetic O{sub 2} evolution rate drops below the rate of respiratory O{sub 2} consumption due to a reversible inhibition of photosystem II, thus leading to an intracellular anaerobiosis. The algal cells survive under these anaerobic conditions by switching their metabolism to a kind of photo-fermentation. Although possessing a functional [Fe]-hydrogenase gene, the cells of Scenedesmus obliquus produce no significant amounts of H{sub 2} under S-depleted conditions. Biochemical ...

2002-12-01

377

Water consumption during solid state sodium borohydride hydrolysis  

Energy Technology Data Exchange (ETDEWEB)

In this paper nickel acetate catalyzed sodium borohydride cartridges have been prepared and hydrolyzed with water for hydrogen production. Two technological solutions have been tested to increase the overall hydrogen yield, namely a porous water diffuser and a hydrophobic membrane. The first was used to improve water diffusion inside the hydride while the second to confine water inside the cartridge. The generated hydrogen flow showed a very reproducible behavior. Hydrogen promptly evolved just after water was pumped into the cartridge. After some initial peaks, a constant hydrogen flow has been recorded for the whole reaction time. The constant flow was related to the presence of the porous diffuser. The use of a hydrophobic membrane to confine the water inside the cartridge allowed to increase the overall hydrogen yield: about 6 water molecules per mol of hydride were required to complete the reaction. The reaction product was identified by XRD as Na{sub 2}B{sub ...

2010-11-15

378

Vibration characteristics of SMA composite beams with different boundary conditions  

Energy Technology Data Exchange (ETDEWEB)

Recently, the development of shape memory alloy (SMA) actuators, in the forms of wire, thin film and stent have been found increasingly in the fields of materials science and smart structures and engineering. The increase in attraction for using these materials is due to their many unique materials, mechanical, thermal and thermal-mechanical properties, which in turn, evolve their subsequent shape memory, pseudo-elasticity and super-elasticity properties. In this paper, a common type of SMA actuator, Nitinol wires, were embedded into advanced composite structures to modulate the structural dynamic responses, in terms of natural frequency and damping ratio by using its shape memory and pseudo-elastic properties. A simple theoretical model is introduced to estimate the natural frequency of the structures before and after actuating the embedded SMA wires. The damping ratios of different SMA composite beams were measured through experimental approaches. The natural ...

2002-12-15

379

Unique effect of mechanical crushing on the electrochemical intercalation of lithium in carbons of different morphologies; Effet unique du broyage mecanique sur l`intercalation electrochimique du lithium dans des carbones de morphologies differentes  

Energy Technology Data Exchange (ETDEWEB)

Lithium ion batteries use an oxide as a positive electrode and a carbon material as a negative electrode. The performances of carbon electrodes have rapidly evolved during the last years thanks to the substitution of soft carbons of Conoco or MCMB-2510 type by graphites (F-399, MCMB-2528) and then by hard carbons. These high capacity carbons (700 mAh/g) have higher service life and volume capacity than graphites but their irreversible losses are greater (>20%). In this work, materials with similar electrochemical performances are prepared by mechanical crushing. Mechanical crushing allows to obtain a wide range of carbon materials with various morphologies, specific surfaces and levels of disorder. The formation of the passivation film is directly linked with the surface of materials. A reaction scheme of the reversible and irreversible capacities has been defined and has permitted to obtain compounds with reversible capacities of 720 mAh/g (2 lithium for 6 ...

1996-12-31

380

The pre-outburst flare of the A 0535+26 August/September 2005 outburst  

CERN Document Server

We study the spectral and temporal behavior of the High Mass X-ray Binary A 0535+26 during a `pre-outburst flare' which took place ~5 d before the peak of a normal (type I) outburst in August/September 2005. We compare the studied behavior with that observed during the outburst. We analyse RXTE observations that monitored A 0535+26 during the outburst. We complete spectral and timing analyses of the data. We study the evolution of the pulse period, present energy-dependent pulse profiles both at the initial pre-outburst flare and close to outburst maximum, and measure how the cyclotron resonance-scattering feature (hereafter CRSF) evolves. We present three main results: a constant period P=103.3960(5)s is measured until periastron passage, followed by a spin-up with a decreasing period derivative of Pdot=(-1.69+/-0.04)x10^(-8)s/s at MJD 53618, and P remains constant again at the end of the main outburst. The spin-up provides evidence for the existence of an ...

2008-01-01

381

The evolving environmental marketplace, using green to make green[An introduction to the U.S. Green Building Council, Performance Rating Systems, LEED as a benchmarking tool in the United States and green economics  

Energy Technology Data Exchange (ETDEWEB)

Using an economic perspective, it is possible to make a case for green buildings and green development practices by placing emphasis on Energy Efficiency and Environmental Design. Several case studies have demonstrated that green buildings save money through reduced consumption of natural resources, electricity and gas both at the building site and at the source of energy. Sound environmental practices and energy efficiency measures improve the environmental conditions throughout the state by reducing power plant emissions and reducing operations and maintenance budgets in the state. The author presented a case study where a green development project was guided and monitored using the Environmental Performance Rating System called Leadership in Energy and Environmental Design (LEED), version 2.0. The work was registered to achieve LEED certification. A brief study on current construction related costs was also included. 2 refs., 1 fig.

2003-07-01

382

The dissolution of Ag(111) electrodes investigated by in situ scanning tunnelling microscopy  

CERN Document Server

voltammetric methods. This remained evident for varying extents of silver dissolution. Ag(111) electrodes were oxidised in 0.1 M KCIO sub 4 solutions by a single swept ORC of 0.77x10 sup - sup 3 C cm sup - sup 2. The final rest potential of the Ag(111) working electrode was over the potential range of -36 mV to 114 mV versus the SCE where the silver islands of the reformed surface are believed to be unstable. Results show that a majority of silver islands of all sizes are stable with time, whereas the silver islands with irregular shapes tended to evolve to exhibit higher degrees of spherical geometry. Additionally, the position of the silver islands did not remain constant during the acquisition of STM images. Results from in situ STM demonstrated that the underlying step-terrace morphology of the Ag(111) electrodes did not remain constant with time. Both macroscale and nanoscale changes to the Ag(111) electrode surface were observed. It is concluded that this is ...

1998-01-01

383

The Wolf-Rayet Content of M33  

CERN Document Server

Wolf-Rayet stars (WRs) are evolved massive stars, and the relative number of WC-type and WN-type WRs should vary with metallicity, providing a sensitive test of stellar evolutionary theory. The observed WC/WN ratio is much higher than that predicted by theory in some galaxies but this could be due to observational incompleteness for WN-types, which have weaker lines. Previous studies of M33's WR content show a galactocentric gradient in the relative numbers of WCs and WNs, but only small regions have been surveyed with sufficient sensitivity to detect all of the WNs. Here we present a sensitive survey for WRs covering all of M33, finding 55 new WRs, mostly of WN type. Our spectroscopy also improves the spectral types of many previously known WRs, establishing in one case that the star is actually a background quasar. The total number of spectroscopically confirmed WRs in M33 is 206, a number we argue is complete to approximately 5%, with most WRs residing in OB ...

2011-01-01

384

The Origin of Life from Primordial Planets  

CERN Document Server

The origin of life and the origin of the universe represent two of the most important problems of science. Both are resolved by hydro-gravitational dynamics (HGD) cosmology (Gibson 1996, Schild 1996, Gibson 2009ab), which predicts frozen primordial hydrogen-helium gas planets in clumps as the dark matter of galaxies. Merging Earth-mass planets formed stars, moons and comets to incubate and cosmically seed the first life. Cometary panspermia (Hoyle and Wickramasinghe 1981, 1982; Wickramasinghe et al. 2009) occurs naturally by HGD mechanisms. Comets and moons are fragments from mergers of stardust covered frozen gas planets in their step-wise growth to star mass. Supernovae from stellar over-accretion of planets produce stardust (C, N, O, P etc.) chemical fertilizer. Planets collect this infected radioactive dust gravitationally, to provide liquid water domains in contact with life nutrients seeded with life prototypes. The first mutating, evolving, life from HGD ...

2010-01-01

385

The Local Environment of the FUor-like Objects AR 6A and 6B  

CERN Document Server

We present new 12CO J=3-2 and HCN J=3-2 molecular line maps of the region surrounding the young star AR 6 using the 15 metre James Clerk Maxwell Telescope. AR 6 was previously found to be a double source with both components exhibiting several characteristics of FU Orionis (FUor) eruptive variable stars. Our data indicates that AR 6, like FU Orionis itself, does not possess a CO outflow and likewise, does not show evidence for large amounts of molecular g as in its circumstellar environment. We conclude that from the near-IR to the sub-mm, AR 6 is similar to FU Orionis in several respects. We interpret the lack of significant dust and molecular gas in the circumstellar environment of AR 6, together with the large near-IR thermal excess, as evidence that the sources have exhausted their natal envelopes, that they have at least small hot circumstellar disks, and that they are more evolved than Class I protostars. This, in itself, suggests that, since FUor eruptions ...

2008-01-01

386

The BPX electrical power system  

International Nuclear Information System (INIS)

This paper reports on the Burning Plasma Experiment (BPX) which when operating at a toroidal field of 8.1 tesla and a plasma current of 10.6 megamps, requires peak power of 1235 megawatts and total pulse energy of over 21 gigajoules. These requirements are twice and over four times the corresponding figures for the Tokamak Fusion Test Reactor (TFTR), respectively. The design of the BPX power system has evolved, along with the tokamak, over a period of several years and has included studies of several alternative approaches. The reapplication of the existing TFTR power and energy facilities has been basic to all approaches. Among the new sources of pulse power and energy that have been considered are: direct utility grid pulsing, new flywheel units, and lead-acid storage batteries. The toroidal field power requirements are the greatest of the BPX subsystems and, fortunately, are sufficiently free of dynamics to allow the consideration of all approaches. Additional ...

1991-10-03

387

TRANS-NEPTUNIAN OBJECTS WITH HUBBLE SPACE TELESCOPE ACS/WFC  

International Nuclear Information System (INIS)

We introduce a novel search technique that can identify trans-Neptunian objects in three to five exposures of a pointing within a single Hubble Space Telescope (HST) orbit. The process is fast enough to allow the discovery of candidates soon after the data are available. This allows sufficient time to schedule follow-up observations with HST within a month. We report the discovery of 14 slow-moving objects found within 50 of the ecliptic in archival data taken with the Wide Field Channel of the Advanced Camera for Surveys. The luminosity function of these objects is consistent with previous ground-based and space-based results. We show evidence that the size distribution of both high and low inclination populations is similar for objects smaller than 100 km, as expected from collisional evolution models, while their size distribution differs for brighter objects. We suggest that the two populations formed in different parts of the protoplanetary disk and after being dynamically mixed ...

2010-10-20

388

Study of the effects of interactions quantum interference and disorder in GaAs and of GaAs jointed to a superconductor; Etude des effets d`interference quantique et de desordre dans GaAs avec interactions et GaAs connecte a un supraconducteur  

Energy Technology Data Exchange (ETDEWEB)

The aim of this thesis is to study the coherent transport in semiconducting-superconducting junctions. The SnPb-GaAs system has been studied. It has been shown that the behaviour of this junction is controlled by the disordered area induced by the annealing of the connection near the interface. For a few resistant junction, a conductance anomaly under the gap has been observed and has been explained by a mesoscopic effect in the limit of the very high disorders. The conductance of more resistant junctions has only been bound to the properties of the very disordered area of the semiconductor. The part of the electron-electron interactions on the phase coherence length and on the conductance has been studied. The evolving of the correction of the conductance due to interactions in magnetic field has been followed. The effect of the spin degeneration suppression in CdTe and the GaAs sign inversion in Shubnikov de Haas oscillations rate has been observed. At last has ...

1997-11-07

389

Spray forming: A numerical investigation of the influence of the gas to melt ratio on the billet surface temperature  

Energy Technology Data Exchange (ETDEWEB)

The relationship between the gas to melt ratio (GMR) and the surface temperature of an evolving billet surface in spray forming is investigated numerically. The basis for the analysis is an integrated approach for modelling the entire spray forming process. This model includes the droplet atomization taking thermal coupling into consideration and the deposition of material at the surface of the billet taking geometrical aspects such as shading into account. The coupling between these two models is accomplished by ensuring that the total droplet size distribution of the spray is the summation of ''local'' droplet size distributions along the r-axis of the spray cone. The criterion for a successful process has been a predefined process window characterised by a desired fraction solid range at a certain distance from the atomizer. Inside this process window, the gas and melt flows have been varied and the influence of the gas and ...

2005-06-01

390

Some computer simulations of semiconductor thin film growth and strain relaxation in a unified atomistic and kinetic model  

Energy Technology Data Exchange (ETDEWEB)

An overview is provided of an evolving atomistic and kinetic model of semiconductor growth that unifies the main features of strain relaxation in low and high lattice misfit heteroepitaxy. The model reveals a kinetic pathway for dislocation formation during growth with little or no energy cost at low misfits, thus providing a way out of the longstanding dilemma of too high dislocation nucleation energies predicted by classical theories of the equilibrium behavior of a fixed number of particles at low misfits. The essential kinetic process underlying the model are identified on the basis of comparison of the predictions of kinetic Monte-Carlo simulations of growth with real-time or in-situ data obtained in such experiments as reflection high-energy electron diffraction (RHEED) and scanning probe microscopy (SPM). Relative significance of these atomistic kinetic processes is shown to naturally lead to strain relaxation via defect initiation at low misfits while ...

1996-12-31

391

Simulations and Analytic Calculations of Bubble Growth During Hydrogen Reionization  

CERN Document Server

We present results from a large volume simulation of Hydrogen reionization. We combine 3d radiative transfer calculations and an N-body simulation, describing structure formation in the IGM, to detail the growth of HII regions around high redshift galaxies. Our simulation tracks 1024^3 dark matter particles, in a box of side length 65.6 Mpc/h. This large volume allows us to accurately characterize the size distribution of HII regions throughout most of the reionization process. At the same time, our simulation resolves many of the small galaxies likely responsible for reionization. It confirms a picture anticipated by analytic models: HII regions grow collectively around highly-clustered sources, and have a well-defined characteristic size, evolving from a sub-Mpc scale at the beginning of reionization to R>10 Mpc towards the end. We present a detailed statistical description of our results, and compare them with a numerical hybrid scheme based on the analytic ...

2006-01-01

392

Self-Interacting Dark Matter Halos and the Gravothermal Catastrophe  

CERN Document Server

We study the evolution of an isolated, spherical halo of self-interacting dark matter (SIDM) in the gravothermal fluid formalism. We show that the thermal relaxation time, $t_r$, of a SIDM halo with a central density and velocity dispersion of a typical dwarf galaxy is significantly shorter than its age. We find a self-similar solution for the evolution of a SIDM halo in the limit where the mean free path between collisions, $\\lambda$, is everywhere longer than the gravitational scale height, $H$. Typical halos formed in this long mean free path regime relax to a quasistationary gravothermal density profile characterized by a nearly homogeneous core and a power-law halo where $\\rho \\propto r^{-2.19}$. We solve the more general time-dependent problem and show that the contracting core evolves to sufficiently high density that $\\lambda$ inevitably becomes smaller than $H$ in the innermost region. The core undergoes secular collapse to a singular state (the ...

2002-01-01

393

Reliability analysis for wind turbines with incomplete failure data collected from after the date of initial installation  

International Nuclear Information System (INIS)

Reliability has an impact on wind energy project costs and benefits. Both life test data and field failure data can be used for reliability analysis. In wind energy industry, wind farm operators have greater interest in recording wind turbine operating data. However, field failure data may be tainted or incomplete, and therefore it needs a more general mathematical model and algorithms to solve the model. The aim of this paper is to provide a solution to this problem. A three-parameter Weibull failure rate function is discussed for wind turbines and the parameters are estimated by maximum likelihood and least squares. Two populations of German and Danish wind turbines are analyzed. The traditional Weibull failure rate function is also employed for comparison. Analysis shows that the three-parameter Weibull function can obtain more accuracy on reliability growth of wind turbines. This work will be helpful in the understanding of the reliability growth of wind energy systems as wind ...

2009-06-01

394

RELAP5/MOD3 code manual. Volume 4, Models and correlations  

International Nuclear Information System (INIS)

The RELAP5 code has been developed for best-estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents and operational transients such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I presents modeling theory and associated numerical schemes; Volume II details instructions for code application and input data preparation; Volume III presents the results of developmental assessment cases that demonstrate and verify the models used in the code; Volume IV discusses in detail ...

1995-08-05

395

Public involvement in the siting of contentious facilities; Lessons from the radioactive waste repository siting programmes in Canada and the United States, with special reference to the Swedish repository siting process  

Energy Technology Data Exchange (ETDEWEB)

This report describes the conclusion of a two-part programme, begun in 1994 with the overall aim of assisting in the development of an acceptable public participation strategy for use in Sweden for the siting of contentious facilities, with particular reference to the ongoing siting programme for a deep repository for spent nuclear fuel. The first part of the work programme, a global review of siting practice, was reported as SSI Rapport 94-15, in November 1994. This recommended further detailed studies of at least two individual programmes, which have now been carried out in Canada and the United States, and are reported on here. They involved face to face meetings with many of the main stake holders in the two programmes and enabled valuable insight to be gained into the potential problems associated with increased public participation, as well as identifying good practice where it exists. The lessons learned have then been applied to the evolving repository ...

1997-08-01

396

Psychoanalysis and psychosomatics: a new synthesis.  

Science.gov (United States)

The usefulness of psychoanalysis to psychosomatic medicine has been limited by the longstanding assumption that the psychological disorder in psychosomatic patients resembles the conflict-based psychopathology that Freud identified in psychoneurotic patients. Recent investigations of the alexithymia construct, and the discovery that social relationships can influence health over the entire life span, have challenged this assumption and created an opportunity for a new and active involvement of psychoanalysis with psychosomatic medicine. In this contribution, I offer a synthesis of contemporary psychoanalytic observations and theories with concepts and research findings from developmental psychology, developmental biology, and the biomedical sciences. The proposed synthesis is consistent with the view that living organisms are self-regulating cybernetic systems; it also extends an evolving new psychosomatic model that conceptualizes illnesses and diseases as ...

1992-01-01

397

PRISM: A Data Management System for High-Throughput Proteomics  

Energy Technology Data Exchange (ETDEWEB)

Advanced proteomic research efforts involving areas such as systems biology or biomarker discovery are enabled by the use of high level informatics tools that allow the effective analysis of large quantities of differing types of data originating from various studies. Performing such analyses on a large scale is not feasible without a computational platform that performs data processing and management tasks. Such a platform must be able to provide high-throughput operation while having sufficient flexibility to accommodate evolving data analysis tools and methodologies. The Proteomics Research Information Storage and Management System (PRISM) provides a platform that serves the needs of the accurate mass and time tag approach developed at PNNL. PRISM incorporates a diverse set of analysis tools and allows a wide range of operations to be incorporated by using a state machine that is accessible to independent, distributed computational nodes. The system has scaled ...

2006-03-01

398

Overview of the US coal liquefaction program  

Science.gov (United States)

The US Department of Energy is carrying out a program of research and development to establish the capability to produce synthetic liquid fuels from coal. According to the National Energy Policy Plan IV, the Assistant Secretary of Fossil Energy is charged with carrying out a program to foster an adequate supply of energy at reasonable cost through innovative, long-term R and D. The payoff for this kind of research is potentially high if the country should need the capability on short notice. However, the research is also high risk in terms of the expectation of process for synthetic fuels to turn a profit for a private sector company. As the date when commercial quantities of synfuels will be needed has retreated before lower real prices of petroleum, the US DOE program for coal liquefaction has evolved to give increasing support to longer range, more exploratory technologies, rather than those nearly developed to the point where commercialization is possible. ...

1986-03-01

399

On the plasma rotation in a straight magnetized filter of a pulsed vacuum arc  

International Nuclear Information System (INIS)

In vacuum arcs of interest for ion deposition, in which a magnetic filter is used, significant plasma rotation about the filter axis can develop. In the present work we present experimental evidence and simplified models to interpret relatively fast rotation of plasma generated in a pulsed vacuum arc with a straight magnetic filter and with a magnetic field strength in the range 52-430 G. The plasma rotation is produced in the first part of the filter (the driving region) where either the expanding or the contracting plasma encounters a mainly axial magnetic field. In the next part of the filter (the rotation region) a quasi-equilibrium is achieved and the plasma does not evolve further significantly. A rigid-rotor type of equilibrium is considered to model the rotation region, with experimentally obtained parameters, and a simple model is employed in the driving region to quantify the magnitude of the plasma rotation. It is found that at the quoted values of the ...

2007-01-21

400

OECD/NEA international Stripa project 1980-1992. Overview volume 3  

International Nuclear Information System (INIS)

The broad objective of the engineered barriers studies was to demonstrate and qualify the use of different materials and techniques for sealing water flow paths in the Stripa granite, the mine excavations and the excavation disturbed zones. As may be anticipated from the application of the observational method that forms the basis for design of geotechnical structures, the programme evolved with the finding being made at Stripa and other underground laboratories. During phase 1, the engineered barriers investigations focussed on the heat affected zone of the repository. Specifically, the response of clay buffers and the interactions between waste containers, clay buffer materials and the rock were studied. The phase 2 investigations examined the feasibility of sealing boreholes shafts and tunnels with clay sealants. The phase 3, studies of the ability to grout and seal fractured granite including the excavation disturbed zone were effected and specific studies into ...

401

Modeling the suppression of boron transient enhanced diffusion in silicon by substitutional carbon incorporation  

Energy Technology Data Exchange (ETDEWEB)

Recent work has indicated that the suppression of boron transient enhanced diffusion (TED) in carbon-rich Si is caused by nonequilibrium Si point defect concentrations, specifically the undersaturation of Si self-interstitials, that result from the coupled out-diffusion of carbon interstitials via the kick-out and Frank--Turnbull reactions. This study of boron TED reduction in Si{sub 1-x-y}Ge{sub x}C{sub y} during 750{sup o}C inert anneals has revealed that the use of an additional reaction that further reduces the Si self-interstitial concentration is necessary to describe accurately the time evolved diffusion behavior of boron. In this article, we present a comprehensive model which includes {l_brace}311{r_brace} defects, boron-interstitial clusters, a carbon kick-out reaction, a carbon Frank--Turnbull reaction, and a carbon interstitial-carbon substitutional (C{sub i}C{sub s}) pairing reaction that successfully simulates carbon suppression of boron TED at ...

2001-08-15

402

Modeling the suppression of boron transient enhanced diffusion in silicon by substitutional carbon incorporation  

International Nuclear Information System (INIS)

Recent work has indicated that the suppression of boron transient enhanced diffusion (TED) in carbon-rich Si is caused by nonequilibrium Si point defect concentrations, specifically the undersaturation of Si self-interstitials, that result from the coupled out-diffusion of carbon interstitials via the kick-out and Frank--Turnbull reactions. This study of boron TED reduction in Si_1_-_x_-_yGe_xC_y during 750"oC inert anneals has revealed that the use of an additional reaction that further reduces the Si self-interstitial concentration is necessary to describe accurately the time evolved diffusion behavior of boron. In this article, we present a comprehensive model which includes #left brace#311#right brace# defects, boron-interstitial clusters, a carbon kick-out reaction, a carbon Frank--Turnbull reaction, and a carbon interstitial-carbon substitutional (C_iC_s) pairing reaction that successfully simulates carbon suppression of boron TED at 750"oC for anneal times ...

2001-08-15

403

Mapping the Dark Side with DEIMOS: Globular Clusters, X-ray Gas, and Dark Matter in the NGC 1407 Group  

CERN Document Server

NGC 1407 is the central elliptical in a nearby evolved galaxy group apparently destined to become a cluster core. We use the kinematics of globular clusters to probe the dynamics and mass profile of the group's center, out to 60 kpc (~10 R_eff) -- the most extended data set to date around an early-type galaxy. This sample consists of 172 GC velocities, most of them newly obtained using Keck/DEIMOS, with a few additional objects identified as DGTOs or as IGCs. We find weak rotation in the GC system's outer parts, with the metal-poor and metal-rich GCs misaligned. The RMS velocity profile declines rapidly to a radius of ~20 kpc, and then becomes flat or rising to ~60 kpc. There is evidence that the GC orbits have a tangential bias that is strongest for the metal-poor GCs -- possibly contradicting theoretical expectations. We construct cosmologically-motivated galaxy+dark halo dynamical models and infer a mass within 60 kpc of ~3x10^12 M_Sun, extrapolating to a virial ...

2008-01-01

404

Ising model for phase separation in alloys with anisotropic elastic interaction. 2: A computer experiment  

Energy Technology Data Exchange (ETDEWEB)

When a metallic alloy is quenched into a miscibility gap, a mixture of two phases develops, whose domain structure then coarsens because of the interfacial energy between the two phases. This spatial arrangement of the domains and the rate at which they evolve may be strongly influenced by elastic interactions. In a recent paper, the authors described a method for simulating the effect of anisotropic elastic interactions in a two-dimensional Ising model of a cubic alloy, using Kawasaki dynamics with the elastic interactions represented by a long-range two-body interaction potential. Here they present the results of such simulations at various temperatures, alloy compositions and misfits (by misfit they mean the difference in size between the two kinds of atom), exhibiting snapshots both of the microscopic configurations (corresponding to experimental measurements using transmission electron microscopy) and of their squared Fourier transforms (corresponding to ...

1996-08-01

405

Interplay of t --> b W Decay and B_q Meson Mixing in Minimal Flavor Violating Models  

CERN Document Server

Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and B_s systems have stimulated many studies of physics beyond the standard model. We investigate anomalous t W d_j interactions as a possible source of new effects in B_{d,s} - bar B_{d,s} oscillations within a model independent approach based on the assumptions of Minimal Flavor Violation. After matching our effective operators onto the low-energy effective Lagrangian describing B_{d,s} meson mixing and evolving it down to the B-mass scale, we extract the preferred ranges of the anomalous t W d_j interactions at the weak scale. These values are then compared to previously considered constraints coming from the rare radiative B --> X_s gamma decay. Finally, we reconsider the associated effects in the t --> b W decays and find ...

2011-01-01

406

Integrating the Integrators - A Roadmap to Success  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy Environmental Management's (DOE-EM) investments in science and technology, as well as science and technology investments associated with other parts of the DOE are aimed at meeting the Departments cleanup goals. These investments, primarily focused on EM's cleanup mission, comprise the Environmental Quality Research and Development (R&D) portfolios. Synchronizing EM's Cleanup Project Managers (operations facility and process owners throughout the DOE complex) operational needs with EM R&D including the extensive work of the six Focus Areas (major thrust areas within DOE-EM) has been a continuing challenge. This recent initiative to better integrate the R&D program is in response to evolving needs within the Department to apply proven system engineering methods to clarify requirements and define EM's process to effectively orchestrate their R&D Program. To optimize this partnership, ...

1999-03-01

407

Integrated model of the shallow and deep hydrothermal systems in the East Mesa area, Imperial Valley, California  

Energy Technology Data Exchange (ETDEWEB)

Geological, geophysical, thermal, petrophysical and hydrological data available for the East Mesa hydrothermal system that are pertinent to the construction of a computer model of the natural flow of heat and fluid mass within the system are assembled and correlated. A conceptual model of the full system is developed and a subregion selected for quantitative modeling. By invoking the Boussinesq approximation, valid for describing the natural flow of heat and mass in a liquid hydrothermal system, it is found practical to carry computer simulations far enough in time to ensure that steady-state conditions are obtained. Initial calculations for an axisymmetric model approximating the system demonstrate that the vertical formation permeability of the deep East Mesa system must be very low (k/sub v/ approx. 0.25 to 0.5 md). Since subsurface temperature and surface heat flow data exhibit major deviations from the axisymmetric approximation, exploratory three-dimensional calculations are ...

1982-01-01

408

Institutt for Energiteknikk - Annual Report 1994  

Energy Technology Data Exchange (ETDEWEB)

Work at Institutt for energiteknikk (IFE) comprises both nuclear and non-nuclear activities. The main nuclear program is centered on the Halden Reactor Project. In 1958, the first Halden Reactor Project Agreement was signed by organisations representing 12 European countries. During 1994 France became a full member and associate membership was established with Russia. Accordingly, 16 countries were participating in the Project by the end of the year. The objectives have evolved from being simply a demonstration of the operation of a boiling heavy-water reactor to becoming a substantial research and development programme covering the domains of human-machine interaction, fuel behaviour, materials testing, water chemistry, and instrumentation. In 1994, significant progress was achieved in all of the areas addressed by the project, including the re-instrumentation of irradiated fuel rods, fission gas release, irradiation-assisted stress corrosion cracking, a ...

1995-12-01

409

Induced current switching development work for the application of ground interrupter switches on the Hydro-Quebec H.V. system  

Energy Technology Data Exchange (ETDEWEB)

Phenomena associated with induced currents and voltages on high voltage transmission lines were discussed. Basic principles were reviewed. Action taken by Hydro-Quebec to assess the importance of associated problems on its grid was described. Hydro-Quebec`s findings and recommendations were compared with those of the International Standard, IEC 1129. It was concluded that for most cases, induced currents and voltages were higher than those listed under Class A recommendations of IEC 1129 as rated switching capabilities for ground switches assigned to this duty. For worst case scenarios, it was also found that, values of induced currents and voltages were lower than those of Class B recommendations. Hydro-Quebec and GEC Alsthom T and D collaborated to design and type test a full range of low cost and efficient ground interrupter switches tailored to Hydro-Quebec`s needs. A list of general application criteria of ground interrupter switches that evolved from that ...

1995-12-31

410

Fuel cells and electricity companies - new risk management opportunities  

International Nuclear Information System (INIS)

'Full text:' Deregulation, distributed generation, combined heat and power, renewables, fuel cells, hydrogen. Power companies are facing a rapidly evolving environment that is testing their ability to effectively deploy capital and earn profits. While recent deregulation trends have shifted the structure of power markets into separating generators from distributors, the improving economic value proposition offered by smaller scale distributed generation technologies - such as fuel cells - would seem to be a conflicting development. In this complex and changing environment, decisions based on the economic reality of the capital markets are likely to prevail. By examining the opportunity to enhance risk management offered by stationary fuel cells, particularly in CHP applications, we provide a context for the issues being discussed in today's sessions focusing on power companies and electric utilities. Our risk management perspective suggests a pathway for ...

2004-09-25

411

Fluxnet Synthesis Dataset Collaboration Infrastructure  

Energy Technology Data Exchange (ETDEWEB)

The Fluxnet synthesis dataset originally compiled for the La Thuile workshop contained approximately 600 site years. Since the workshop, several additional site years have been added and the dataset now contains over 920 site years from over 240 sites. A data refresh update is expected to increase those numbers in the next few months. The ancillary data describing the sites continues to evolve as well. There are on the order of 120 site contacts and 60proposals have been approved to use thedata. These proposals involve around 120 researchers. The size and complexity of the dataset and collaboration has led to a new approach to providing access to the data and collaboration support and the support team attended the workshop and worked closely with the attendees and the Fluxnet project office to define the requirements for the support infrastructure. As a result of this effort, a new website (http://www.fluxdata.org) has been created to provide access to the Fluxnet ...

2008-02-06

412

Evolution of the triangle zone in the Rocky Mountains Foothills near Coalspur, Central Alberta  

Energy Technology Data Exchange (ETDEWEB)

A triangle zone, which commonly occurs along the external margin of a foreland thrust and fold belt with a buried thrust front, is underlain by a subhorizontal, blind, foreland-verging thrust that ends against a foreland-dipping, hinterland-verging thrust. These contemporaneous thrusts, active towards the end of orogenesis, enclose an intercutaneous wedge that moved towards the foreland. During orogenesis, a triangle zone evolves through periodic replacement of faults bounding the active wedge. Replacements occur in cycles during each of which a lower fault tends to be replaced by one in a lower stratigraphic horizon, an upper fault by one farther away from the foreland. Each cycle ends with the lower fault moving to a younger horizon where it joins a new, more external upper fault. Near Coalspur, the triangle zone exposes the remnants of several wedges involving Upper Cretaceous and Palaeocene molasse. Most of these wedges developed during the last cycle but one ...

1987-08-01

413

Evolution of spiral galaxies in modified gravity  

CERN Document Server

We compare N-body simulations of isolated galaxies performed in both frameworks of modified Newtonian dynamics (MOND) and Newtonian gravity with dark matter (DM). We have developed a multigrid code able to efficiently solve the modified Poisson equation derived from the Lagrangian formalism AQUAL. We take particular care of the boundary conditions that are a crucial point in MOND. The 3-dimensional dynamics of initially identical stellar discs is studied in both models. In Newtonian gravity the live DM halo is chosen to fit the rotation curve of the MOND galaxy. For the same value of the Toomre parameter (Q_T), galactic discs in MOND develop a bar instability sooner than in the DM model. In a second phase the MOND bars weaken while the DM bars continue to grow by exchanging angular momentum with the halo. The bar pattern speed evolves quite differently in the two models: there is no dynamical friction on the MOND bars so they keep a constant pattern speed while the ...

2007-01-01

414

Evaluating technologies for tactical information management in net-centric systems  

Science.gov (United States)

Recent trends in distributed real-time and embedded (DRE) systems motivate the development of tactical information management capabilities that ensure the right information is delivered to the right place at the right time to satisfy quality of service (QoS) requirements in heterogeneous environments. A promising approach to building and evolving large-scale and long-lived tactical information management systems are standards-based QoS-enabled publish/subscribe (pub/sub) platforms that enable applications to communicate by publishing information they have and subscribing to information they need in a timely manner. Since there is little existing evaluation of how well these platforms meet the performance needs of tactical information management, this paper provides two contributions: (1) it describes three common architectures for the OMG Data Distribution Service (DDS), which is a QoS-enabled pub/sub platform standard, and (2) it evaluates three implementations of ...

2007-05-01

415

Different Evolutionary Stages in the Massive Star Forming Region S255 Complex  

CERN Document Server

To understand evolutionary and environmental effects during the formation of high-mass stars, we observed three regions of massive star formation at different evolutionary stages that reside in the same natal molecular cloud. Methods. The three regions S255IR, S255N and S255S were observed at 1.3 mm with the Submillimeter Array (SMA) and followup short spacing information was obtained with the IRAM 30m telescope. Near infrared (NIR) H + K-band spectra and continuum observations were taken for S255IR with VLT-SINFONI to study the different stellar populations in this region. The combination of millimeter (mm) and near infrared data allow us to characterize different stellar populations within the young forming cluster in detail. While we find multiple mm continuum sources toward all regions, their outflow, disk and chemical properties vary considerably. The most evolved source S255IR exhibits a collimated bipolar outflow visible in CO and H2 emission, the outflows ...

2010-01-01

416

Design of a welltest for determining two-phase hydraulic properties  

Energy Technology Data Exchange (ETDEWEB)

This report describes the design of a well test to determine two-phase hydraulic properties of a low permeability, low porosity formation. Estimation of gas-related parameters in such formations is difficult using standard pumping tests mainly because of the strong fluctuations in the pressure and flow rate data which are a consequence of gas bubbles evolving in the test interval. Even more important is the fact that the data do not allow distinguishing among alternative conceptual models. The estimated parameters are therefore uncertain, highly correlated, and ambiguous. In this study we examine a test sequence that could be appended to a standard hydraulic testing program. It is shown that performing a series of water and gas injection tests significantly reduces parameter correlations, thus decreasing the estimation error. Moreover, the extended test sequence makes possible the identification of the model that describes relative permeabilities and capillary ...

1995-01-01

417

Depth dependence of defect evolution and TED during annealing  

Energy Technology Data Exchange (ETDEWEB)

A quantitative transmission electron microscopy (TEM) study on the depth profile of extended defects, formed after Si implantation, has been carried out. Two different Si{sup +} implant conditions have been considered. TEM analysis for the highest energy/dose shows that {l_brace}1 1 3{r_brace} defects evolve into dislocation loops whilst the defect depth distribution remains unchanged as a function of annealing time. For the lowest energy/dose, {l_brace}1 1 3{r_brace} defects grow and dissolve while the defect band shrinks preferentially on the surface side. At the same time, extraction of boron transient enhanced diffusion (TED) as a function of depth shows a decrease of the supersaturation towards the surface, starting at the location of the defect band. The study clearly shows that in these systems the silicon surface is the principal sink for interstitials. The results provide a critical test of the ability of physical models to simulate defect evolution and ...

2004-02-01

418

Depth dependence of defect evolution and TED during annealing  

International Nuclear Information System (INIS)

A quantitative transmission electron microscopy (TEM) study on the depth profile of extended defects, formed after Si implantation, has been carried out. Two different Si"+ implant conditions have been considered. TEM analysis for the highest energy/dose shows that #left brace#1 1 3#right brace# defects evolve into dislocation loops whilst the defect depth distribution remains unchanged as a function of annealing time. For the lowest energy/dose, #left brace#1 1 3#right brace# defects grow and dissolve while the defect band shrinks preferentially on the surface side. At the same time, extraction of boron transient enhanced diffusion (TED) as a function of depth shows a decrease of the supersaturation towards the surface, starting at the location of the defect band. The study clearly shows that in these systems the silicon surface is the principal sink for interstitials. The results provide a critical test of the ability of physical models to simulate defect ...

2004-02-01

419

Deformed-coal structure and control to coal-gas outburst  

Energy Technology Data Exchange (ETDEWEB)

Based on techniques of organic solvent extraction and a thermal model experiments of coal-related hydrocarbon, the variation of coal structure and the character of deformed coal-related hydrocarbons were studied when the coal seam at Piagdingshan mine, China was modified by tectonic stress. The results show that the extraction ratio by n-hexane and benzene from the deformed coal approaches that form normal coal, but the extraction ratio by chloroform from the deformed coal is two times more than that from normal coal. The deformed coal has higher solvable low-molecular weight compounds than normal coal. The intermolecular force of deformed coal is relatively small. The deformed coal has low strength and high adsorption capacity, and these determine the outbreak of coal-gas outburst. The extraction yields by chloroform can be taken as an index of forecast risks of coal-gas outburst. The potentially of generating hydrocarbon from the deformed coal is relatively low. Deformed coal ...

2007-03-15

420

Data Stream Clustering: Challenges and Issues  

CERN Document Server

Very large databases are required to store massive amounts of data that are continuously inserted and queried. Analyzing huge data sets and extracting valuable pattern in many applications are interesting for researchers. We can identify two main groups of techniques for huge data bases mining. One group refers to streaming data and applies mining techniques whereas second group attempts to solve this problem directly with efficient algorithms. Recently many researchers have focused on data stream as an efficient strategy against huge data base mining instead of mining on entire data base. The main problem in data stream mining means evolving data is more difficult to detect in this techniques therefore unsupervised methods should be applied. However, clustering techniques can lead us to discover hidden information. In this survey, we try to clarify: first, the different problem definitions related to data stream clustering in general; second, the specific ...

2010-01-01

421

Cosmic evolution of the atomic and molecular gas content of galaxies  

CERN Document Server

We study the evolution of the cold gas content of galaxies by splitting the interstellar medium into its atomic and molecular hydrogen components, using the galaxy formation model GALFORM in the LCDM framework. We calculate the molecular-to-atomic hydrogen mass ratio, H2/HI, in each galaxy using two different approaches; the pressure-based empirical relation of Blitz & Rosolowsky and the theoretical model of Krumholz, McKeee & Tumlinson, and apply them to consistently calculate the star formation rates of galaxies. We find that the model based on the Blitz & Rosolowsky law predicts an HI mass function, CO(1-0) luminosity function, correlations between the H2/HI ratio and stellar and cold gas mass, and infrared-CO luminosity relation in good agreement with local and high redshift observations. The HI mass function evolves weakly with redshift, with the number density of high mass galaxies decreasing with increasing redshift. In the case of the H2 mass ...

2011-01-01

422

COLLISIONAL AND LUMINOSITY EVOLUTION OF A DEBRIS DISK: THE CASE OF HD 12039  

International Nuclear Information System (INIS)

Extrasolar debris disks that are bright enough to be observed are dense enough to be collision-dominated; i.e., the small grains that produce their infrared excess have collisional lifetimes shorter than their Poynting-Robertson decay times. This paper describes a numerical code for the modeling of such disks, including accretion and gravitational stirring as well as disruptive collisions. A constraint relating the mass of a debris disk and the sizes of the largest embedded bodies to its luminosity is demonstrated. The collisional code is applied to the debris disk around HD 12039, which has been intensively observed by the Spitzer Space Telescope. The evolution in time of the disk's luminosity is computed for a range of initial disk masses and planetesimal sizes. The luminosity at a given age depends on both the initial disk mass and the initial size of the planetesimals. Luminosity decays more rapidly for massive disks due to the combination of collisional depletion of small bodies ...

2010-10-20

423

Bonneville Power Administration, Office of Engineering 10-Year Plan, 1992-2001 : Draft.  

Energy Technology Data Exchange (ETDEWEB)

For over 50 years, the Bonneville Power Administration (BPA) has evolved to supply electric power to more than 170 customer utilities and direct service industries across 14,800 miles of high voltage transmission lines. BPA's Office of Engineering provides the planning, development, and engineering for the required expansion, upgrade, and replacement of the transmission system. The purpose of this 10-Year Plan is to present strategies to maintain a reliable energy delivery system within changing public, business, technological, and environmental climates. The issues and trends discussed in this document and our strategies for addressing them provide the background for the Office of Engineering programs and projects. With a budget in the hundreds of millions annually and increasing public concern, we welcome the opportunity to communicate with our customers. In addition to the factors, trends and issues described in this document are two appendices ...

1992-05-01

424

Bonneville Power Administration, Office of Engineering 10-Year Plan, 1992-2001 : Draft.  

Energy Technology Data Exchange (ETDEWEB)

For over 50 years, the Bonneville Power Administration (BPA) has evolved to supply electric power to more than 170 customer utilities and direct service industries across 14,800 miles of high voltage transmission lines. BPA`s Office of Engineering provides the planning, development, and engineering for the required expansion, upgrade, and replacement of the transmission system. The purpose of this 10-Year Plan is to present strategies to maintain a reliable energy delivery system within changing public, business, technological, and environmental climates. The issues and trends discussed in this document and our strategies for addressing them provide the background for the Office of Engineering programs and projects. With a budget in the hundreds of millions annually and increasing public concern, we welcome the opportunity to communicate with our customers. In addition to the factors, trends and issues described in this document are two appendices containing ...

1992-05-01

425

Biased power spectrum and bispectrum for an ensemble of three-dimensional scale free numerical simulations  

CERN Document Server

We examine the effect of a threshold bias on the power spectrum and the bispectrum in an ensemble of numerical simulations (Gaussian initial perturbations with power law spectra P(k) \\sim k^n, n=+1, 0, -1, -2) and compare our results with theoretical predictions. Our simulations are evolved sufficiently that on the scale where we apply the threshold the rms fluctuation has developed significantly into the nonlinear regime. Thus, predictions based on perturbation theory do not necessarily apply. Nevertheless, we find our results for the power spectrum, biased power simply amplified by a numerical factor, follow predicted trends, far beyond the regime where perturbation theory is expected to be valid. We find that the biased bispectrum continues to follow the so-called hierarchical form, with reduced three-point amplitude Q \\approx 1 in the strongly nonlinear regime, independent of initial spectrum. In the quasi-linear perturbative regime the three-point amplitude ...

1994-01-01

426

Behavioural evidence for mental time travel in nonhuman animals.  

Science.gov (United States)

If episodic memory is an adaptation, it must have evolved to benefit present or future survival and reproduction, rather than to provide an accurate record of the past per se. Recent research has documented various links between the ability to construct episodes of the past and imagine potential future episodes, and it has been argued that the former may be a design feature of the latter. Thus, claims about the existence of episodic memory in non-verbal organisms may be evaluated by examining behavioural evidence for foresight. Here we review recent data on foresight in animals and conclude that the evidence to suggest episodic memory so far is equivocal. We suggest specific experimental criteria that could provide stronger evidence. We maintain that there must be uniquely human traits for which there are no animal models and it remains possible that mental time travel depends on several such traits. Identification of what precisely is unique about the human ...

2009-12-03

427

Atomistic calculations of ion implantation in Si: Point defect and transient enhanced diffusion phenomena  

Energy Technology Data Exchange (ETDEWEB)

A new atomistic approach to Si device process simulation is presented. It is based on a Monte Carlo diffusion code coupled to a binary collision program. Besides diffusion, the simulation includes recombination of vacancies and interstitials, clustering and re-emission from the clusters, and trapping of interstitials. We discuss the simulation of a typical room-temperature implant at 40 keV, 5{times}10{sup 13} cm{sup {minus}2} Si into (001)Si, followed by a high temperature (815{degree}C) anneal. The damage evolves into an excess of interstitials in the form of extended defects and with a total number close to the implanted dose. This result explains the success of the {open_quote}{open_quote}+1{close_quote}{close_quote} model, used to simulate transient diffusion of dopants after ion implantation. It is also in agreement with recent transmission electron microscopy observations of the number of interstitials stored in (311) defects. {copyright} {ital 1996 American ...

1996-01-01

428

Atomistic calculations of ion implantation in Si: Point defect and transient enhanced diffusion phenomena  

International Nuclear Information System (INIS)

A new atomistic approach to Si device process simulation is presented. It is based on a Monte Carlo diffusion code coupled to a binary collision program. Besides diffusion, the simulation includes recombination of vacancies and interstitials, clustering and re-emission from the clusters, and trapping of interstitials. We discuss the simulation of a typical room-temperature implant at 40 keV, 5x10"1"3 cm"-"2 Si into (001)Si, followed by a high temperature (815 degree C) anneal. The damage evolves into an excess of interstitials in the form of extended defects and with a total number close to the implanted dose. This result explains the success of the open-quote open-quote+1 close-quote close-quote model, used to simulate transient diffusion of dopants after ion implantation. It is also in agreement with recent transmission electron microscopy observations of the number of interstitials stored in (311) defects. copyright 1996 American Institute of Physics.

429

An enigmatic HI cloud  

CERN Document Server

The discovery of an HI cloud with peculiar properties at equatorial coordinates (J2000) ra=07h49m, dec=04d30m is presented. The HI object was detected at 21cm using the 300-m NAIC Arecibo telescope. Subsequent follow-up high-resolution observations with the NRAO Very Large Array (VLA) telescope at L-Band revealed more details about its morphology. The most intriguing aspect of the object is the clear velocity gradient of 1 km/s, which is present in the data, an indication of either rotation or expansion. The gas appears to be cold, and its morphology is somewhat elliptical with clumpy substructure. Assuming disk rotation, the dynamical mass could be determined as a function of distance.Depending on the exact nature of the velocity gradient in the HI cloud, we can reach some preliminary conclusions about the nature of the object. Expansion would imply association with a circumstellar envelope of an evolved AGB star, while in the case of rotation, a comparison ...

2008-01-01

430

Amyloidosis  

International Nuclear Information System (INIS)

The subjects covered in this Symposium range through almost every clinical medical specialty. From an average of one paper in each of the past three Symposiums, the explosive interest in cerebral amyloidosis has led to the presentation of 12 papers on this subject in the present volume. The genetically predisposed familial amyloidotic processes, such as the polyneuropathies and familial Mediterranean fever have also stimulated extensive and intriguing investigations which have revealed the striking effect of a single amino acid substitution in transforming a normal protein into a lethal ''amyloidogenic'' one. This Symposium clearly depicts the advances since the first amyloid fibril protein was definitively identified and defined 14 years ago. Since all amyloid fibril proteins so far described are variants of normal proteins, attention to gene abnormalities now becomes a significant focus as well as the pathogenic sequences which lead in these cases to twisted #BETA#-pleated sheet ...

1984-11-09

431

THE EVOLUTION OF THE STAR FORMATION RATE OF GALAXIES AT 0.0 #<=# z #<=# 1.2  

International Nuclear Information System (INIS)

We present the 24 #mu#m rest-frame luminosity function (LF) of star-forming galaxies in the redshift range 0.0 #<=# z #<=# 0.6 constructed from 4047 spectroscopic redshifts from the AGN and Galaxy Evolution Survey of 24 #mu#m selected sources in the Booetes field of the NOAO Deep Wide-Field Survey. This sample provides the best available combination of large area (9 deg"2), depth, and statistically complete spectroscopic observations, allowing us to probe the evolution of the 24 #mu#m LF of galaxies at low and intermediate redshifts while minimizing the effects of cosmic variance. In order to use the observed 24 #mu#m luminosity as a tracer for star formation, active galactic nuclei (AGNs) that could contribute significantly at 24 #mu#m are identified and excluded from our star-forming galaxy sample based on their mid-IR spectral energy distributions or the detection of X-ray emission. Optical emission line diagnostics are considered for AGN identification, but we find that 24 ...

2010-08-01

432

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2001 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 2001 annual report covers the fifth year of sampling of this multi-year study. In 2001 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon rivers. The Snake River was sampled between Lower Granite Dam (rkm 174) and the mouth of the Salmon River (rkm 303), and the Salmon River was sampled from its mouth upstream to Hammer Creek (rkm 84). A total of 45,907 hours of setline effort and 186 hours of hook-and-line effort was employed in 2001. A total of 390 white sturgeon were captured and tagged in the Snake River and 12 in the Salmon River. Since 1997, 36.1 percent of the tagged white sturgeon have been recaptured. ...

2003-03-01

433

Use of fuel cells to meet military requirements for mobile power  

International Nuclear Information System (INIS)

'Full text:' The use of fuel cell technology in military applications will depend on safe, high energy density systems being developed. An important part of using this technology is also the development of alternative hydrogen producing fuels with high energy densities and are easy to transport. Fuel cells are now a very large R and D effort for several military applications around the world. The major reason is because of the high power demands needed requires electrical energy sources that far exceed the capabilities of batteries currently being fielded for portable applications. Fuel cells are regarded as highly efficient, tactical energy converters that can be adapted for wide range of power requirements. They are potentially the lowest weight power source when coupled with batteries or capacitors to form hybrid systems. Generally electrical power is needed to support a number of applications from ultra-high power for electrical pulses (radios, sensors) to ...

2004-09-25

434

Truck tactics: dispatch from Vancouver  

Energy Technology Data Exchange (ETDEWEB)

Any mine that uses haultrucks has a dispatching system of some sort, even if it is only a very basic and simple arrangement. The larger, more complex operations have found that, if properly applied, automated computerised dispatching improves the productivity of the equipment as well as improving overall control and reporting. However, not every mine can justify going this far; in these cases a computerised monitoring and reporting system with manual dispatching can still give considerable benefits. Wenco International Mining Systems of Vancouver supplies its computerised system to three different specification levels to suit most open pit mining operations. The article describes the 3 PMCSs (Production Monitoring and Control System) available: PMCS 1000, for monitoring and reporting only; PMCS 2000, for dispatching to maximise production; and PMCS 3000, for dispatching with optimised product quality and production. The major components of the PMCS are: mobile data terminals fitted to ...

1991-11-01

435

The review of radioactive waste management in the world  

International Nuclear Information System (INIS)

Radioactive waste is generally classified on the basis of how much radiation and the type of radiation it emits as well as the length of time over which it will continue to emit radiation. Many activities dealing with radioactive materials produce nuclear wastes, including civilian nuclear power programs (nuclear Power plant operations and nuclear fuel-cycle activities), defense nuclear programs (nuclear weapons production, naval nuclear reactor programs, and related R and D), and industrial and institutional activities (scientific research, medical operations, and other industrial uses of Radioisotopic sources or Radio chemicals). To minimize the potential adverse health and environment impacts to people and other systems including of animals, plant and etc, during the entire lifetime of the radionuclides involved, nuclear waste must be carefully and properly managed. The scope of nuclear - waste management encompasses generation, processing (treatment and ...

436

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

CERN Document Server

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

2008-01-01

437

Status of IAEA CRP on Study of Process-Losses in Separation Processes in Partitioning and Transmutation Systems in View of Minimizing Long-Term Environmental Impacts  

Science.gov (United States)

Coordinated Research Project (CRP) was initiated in 2002 by IAEA to enable Member States in developing methodologies for reducing radio-toxic discharge to the environment from nuclear fuel cycle activities and in paving the way for sustainability of nuclear energy. In the past three Research Coordination Meetings (RCM), the following areas of research were examined upon: (1)Basic studies to compare dry partitioning process with aqueous partitioning process; (2)Defining proliferation resistance attributes of partitioning processes; (3) Advanced characterization methods for actinides for measuring the possible material holdup;( 4)Minimization of actinides losses in the waste fraction from the partitioning process;(5)Establishment of separation criteria of partitioning process to minimize environmental impact; and (6)Defining environmental impact associated with partitioning processes. The final TECDOC is currently being prepared to summarize the activities of this ...

2007-07-01

438

Spontaneous emission spectra and simulating multiple spontaneous generation coherence in a five-level atomic medium  

Science.gov (United States)

We investigate the features of the spontaneous emission spectra in a coherently driven cold five-level atomic system by means of a radio frequency (rf) or microwave field driving a hyperfine transition within the ground state. It is shown that a few interesting phenomena such as spectral-line narrowing, spectral-line enhancement, spectral-line suppression, and spontaneous emission quenching can be realized by modulating the frequency and intensity of the rf-driving field in our system. In the dressed-state picture of the coupling and rf-driving fields, we find that this coherently driven atomic system has three close-lying levels so that multiple spontaneously generated coherence (SGC) arises. Our considered atomic model can be found in real atoms, such as rubidium or sodium, so a corresponding experiment can be done to observe the expected phenomena related to SGC reported by Fountoulakis et al. [Phys. Rev. A 73, 033811 (2006)], since no rigorous conditions are ...

2006-09-15

439

Spectroscopic studies on the interaction of the antibiotic lasalocid A (x-537a) with technetium (V) ions in methanol  

International Nuclear Information System (INIS)

In the present study, the authors examine the interactions of pentavalent technetium ions (TcO/sup 3+/) with the basic form of the lasalocid A in pure methanol solvent and in methanol-water mixtures. There are a number of reasons for such a study. First, the interactions of technetium ions with biologically important compounds are of considerable importance owing to the widespread use of /sup 99m/Tc in diagnostic radio-imaging. Second, lasalocid A is known to transport metal ions across phospholipid bilayer membranes and between the aqueous cores of phospholipid inverse micelles. Third, lasalocid A is known to bind and solubilize metal ions in bulk organic liquid phases. Fourth, the conformation adopted by lasalocid A on interaction with TcO/sup 3+/ appears to be different than those found in most other cases and circumstances. Fifth, it may also be possible to use the competition of TcO/sup 3+/ with other, physiologically relevant cations (Na/sup +/, K/sup +/, ...

440

Salivary cortisol assessment in the evaluation of hypothalamic-pituitary-adrenal function  

International Nuclear Information System (INIS)

A simple, short and sensitive direct radio-immunoassay technique for the determination of salivary cortisol concentration was employed to assess saliva as a medium for evaluating cortisol response during endocrine testing in 9 controls and 40 patients. Results in controls suggested that an adequate salivary cortisol response to insulin hypoglycaemia was an increase of 150% above the basal value with a minimum peak of 15 nmol/l. Thirty-three patients were classified as being either good or poor responders to insulin hypoglycaemia on the basis of criteria for plasma cortisol levels. When the defined salivary cortisol response was used for assessment, all 33 patients were correctly categorized into the same response groups. The salivary cortisol response to intramuscular tetracosactin in 3 patients and an intravenous dexamethasone infusion in 4 patients confirmed the value of saliva as an assay medium. These studies show that the salivary cortisol response parallels ...

1984-05-01

441

Role of accelerator mass spectrometry in biological dosimetry  

International Nuclear Information System (INIS)

Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying the binding of labeled chemicals to DNA. The very toxic and ...

1992-04-05

442

Radio-frequency optical double-resonance spectrum of SrF: the X/sup 2/. sigma. /sup +/ state  

Energy Technology Data Exchange (ETDEWEB)

The isotropic and anisotropic hyperfine constants of the ground X/sup 2/..sigma../sup +/ state of /sup 88/SrF and /sup 86/SrF are reported. Vibrational and rotational dependences are studied in a Dunham expansion analysis. Furthermore, the vibrational, rotational, and isotopic dependence of the spin-rotation constant is determined. The following values are obtained for X/sup 2/..sigma../sup +/, ..nu.. = 0, in /sup 88/SrF: ..gamma../sub 0/ = 74.79485 MHz, ..gamma../sub 1/ = 5.752 x 10/sup -5/ MHz, ..gamma../sub 2/ = -6.3 x 10/sup -10/ MHz, b/sub 0/ = 97.0834 MHz, b/sub 1/ = -3.300 x 10/sup -4/ MHz, c/sub 0/ = 30.268 MHz, C/sub I/ = 0.00230 MHz, where ..gamma.. is the spin-rotation parameter, b and c are the Frosch and Foley hyperfine parameters, and C/sub I/ is a nuclear spin-rotation correction. 4 figures, 4 tables.

1981-01-01

443

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System  

Energy Technology Data Exchange (ETDEWEB)

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} ...

1998-01-16

444

QoS-Aware Joint Policies in Cognitive Radio Networks  

CERN Document Server

One of the most challenging problems in Opportunistic Spectrum Access (OSA) is to design channel sensing-based protocol in multi secondary users (SUs) network. Quality of Service (QoS) requirements for SUs have significant implications on this protocol design. In this paper, we propose a new method to find joint policies for SUs which not only guarantees QoS requirements but also maximizes network throughput. We use Decentralized Partially Observable Markov Decision Process (Dec-POMDP) to formulate interactions between SUs. Meanwhile, a tractable approach for Dec-POMDP is utilized to extract sub-optimum joint policies for large horizons. Among these policies, the joint policy which guarantees QoS requirements is selected as the joint sensing strategy for SUs. To show the efficiency of the proposed method, we consider two SUs trying to access two-channel primary users (PUs) network modeled by discrete Markov chains. Simulations demonstrate three interesting findings: 1- Optimum joint ...

2010-01-01

445

Probing the Origins of the CIV and Fe Kalpha Baldwin Effect  

CERN Document Server

We use UV/optical and X-ray observations of 272 radio-quiet Type 1 AGNs and quasars to investigate the CIV Baldwin Effect (BEff). The UV/optical spectra are drawn from the Hubble Space Telescope, International Ultraviolet Explorer and Sloan Digital Sky Survey archives. The X-ray spectra are from the Chandra and XMM-Newton archives. We apply correlation and partial-correlation analyses to the equivalent widths, continuum monochromatic luminosities, and alpha_ox, which characterizes the relative X-ray to UV brightness. The equivalent width of the CIV 1549 emission line is correlated with both alpha_ox and luminosity. We find that by regressing l_UV with EW(CIV) and alpha_ox, we can obtain tighter correlations than by regressing l_UV with only EW(CIV). Both correlation and regression analyses imply that l_UV is not the only factor controlling the changes of EW(CIV); alpha_ox (or, equivalently, the soft X-ray emission) plays a fundamental role in the formation and ...

2009-01-01

446

Pre-transitional disk nature of the AB Aur disk  

CERN Document Server

The disk around AB Aur was imaged and resolved at 24.6\\,$\\mu$m using the Cooled Mid-Infrared Camera and Spectrometer on the 8.2m Subaru Telescope. The gaussian full-width at half-maximum of the source size is estimated to be 90 $\\pm$ 6 AU, indicating that the disk extends further out at 24.6\\,$\\mu$m than at shorter wavelengths. In order to interpret the extended 24.6\\,$\\mu$m image, we consider a disk with a reduced surface density within a boundary radius $R_c$, which is motivated by radio observations that suggest a reduced inner region within about 100 AU from the star. Introducing the surface density reduction factor $f_c$ for the inner disk, we determine that the best match with the observed radial intensity profile at 24.6\\,$\\mu$m is achieved with $R_c$=88 AU and $f_c$=0.01. We suggest that the extended emission at 24.6\\,$\\mu$m is due to the enhanced emission from a wall-like structure at the boundary radius (the inner edge of the outer disk), which ...

2010-01-01

447

Performance enhancement of a compact radio frequency ion source by the injection of supplemental electrons  

Energy Technology Data Exchange (ETDEWEB)

A versatile, high brightness, volume type, low power RF source, capable of producing positive ion beams with intensities as high as 1 mA from gaseous feed materials and microamperes of negative ion beams has been characterized. The source can also be operated as a plasma sputter negative ion source to generate up to 1 mA of a selected species. The performance of the source in the positive and negative volume modes of operation can be greatly enhanced by addition of a removable, water cooled filament assembly in place of the negative sputter probe. For examine, the material utilization efficiencies of gaseous feed species can be more than doubled, total current intensities increased up to 40%, molecular dissociation fractions increased by 20% and minimum operating pressures reduced by a factor of four when operated in the volume mode. These added electrons also favorably effect, as a consequence of lower pressures, the emittance apparently through a reduction of scattering in the beam ...

1995-07-01

448

Novel InN growth method under In-rich condition on GaN/Al2O3(0001) templates  

International Nuclear Information System (INIS)

A novel technique is proposed for the growth of an InN film on a GaN/Al2O3(0001) template by radio-frequency plasma-excited molecular beam epitaxy (RF-MBE). The method involves 1) InN growth under an In-rich condition and 2) additional nitrogen radical irradiation after the InN growth under an In-rich condition. Excess In that appeared on the InN surface in the InN growth under an In-rich condition is transformed to InN by the additional nitrogen radical irradiation. The effective V/III ratio is easily controlled by monitoring the intensity in a reflection high-energy electron diffraction (RHEED) pattern. The growth of the InN film by repeating the InN growth under an In-rich condition and the additional nitrogen radical irradiation is also demonstrated. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2009-06-01

449

Non-hematological tumors of head and neck region in the pediatric age group in a tertiary care cancer center  

British Library Electronic Table of Contents (United Kingdom)

Purpose To analyze the clinical profile, management and outcome of non-hematological tumors in head and neck region in children less than 18?years of age. Patients and methods Medical records of patients (0?18?years) presenting with non-hematological tumors of head and neck region from 2000 to 2010 were reviewed. Result Out of the 78 patients identified, 50 were males with median age of 14?years (3?months to 18?years). Histologically, 58 out of the 78 patients had malignant tumors and 20 were metastatic at presentation. Common site of tumor origin was noted as thyroid (23/78), salivary glands (21/78) and nasopharynx (13/78). Out of 78 patients, 44 patients were treated by surgery, 26 patients received radiation and 13 patients received chemotherapy, while 9 patients received radio-iodine (...

2011-01-01

450

Mid-latitude scintillation model. Technical report, 1 November 1985-31 October 1986  

Energy Technology Data Exchange (ETDEWEB)

Radiowave scintillation in the presence of ionospheric disturbances has the potential to disrupt numerous transionospheric radio and radar systems. This report describes development of a model characterizing the plasma density irregularities that produce scintillation in the naturally disturbed mid-latitude F layer. The model will be incorporated into Program WBMOD, which includes subroutines for computing both link geometry and scintillation indices, the latter by means of phase screen diffraction theory. Earlier versions of WBMOD, were based on extensive analysis of scintillation data collected in the auroral and equatorial zones in Wideband Satellite Mission. The model described herein is based on similarly extensive analysis of Wideband data from one mid latitude station and of data collected from HiLat satellite at another mid latitude station. The model describes irregularities at an effective height of 350 km that are isotropic across the geomagnetic field ...

1986-10-31

451

Metallic implants and exposure to radiofrequency radiation  

International Nuclear Information System (INIS)

There is increasing use of radiofrequency radiation (RFR) in industry for communications, welding, security, radio, medicine, navigation etc. It has been recognised for some years that RFR may interact with cardiac pacemakers and steps have been taken to prevent this interference. It is less well recognised that other metallic implants may also act as antennas in an RFR field and possibly cause adverse health effects by heating local tissues. There are a large and increasing number of implants having metal components which may be found in RFR workers. These implants include artificial joints, rods and plates used in orthopaedics, rings in heart valves, wires in sutures, bionic ears, subcutaneous infusion systems and (external) transdermal drug delivery patches"1. The physician concerned with job placement of such persons requires information on the likelihood of an implant interacting with RFR so as to impair health. The following outlines the approach developed in ...

452

Lubrication properties of molybdenum disulfide films deposited by RF sputtering method  

Energy Technology Data Exchange (ETDEWEB)

A radio frequency sputtering apparatus with a pair of targets has been developed for depositing a film of uniform thickness onto a complex-geometric specimen such as the retainer of a ball bearing. The deposition characteristics of the apparatus were compared with those of the conventional sputtering apparatus. Lubrication properties of MoS/sub 2/ films made by these devices were also compared under a variety of conditions. Finally, friction and wear of MoS/sub 2/ films applied to angular-contact type ball bearings of 20 mm bore were studied in air, nitrogen and vacuo. The two-target sputtering has an advantage mentioned above. However, the films deposited by the method exhibited a rather short wear life because of the temperature rise of the substrate during ion bombardment and during the sputtering process. This temperature dependence was observed in films on those substrates that had been heated with a built-in heater during sputtering. The film thickness ...

1986-01-01

453

Long-life bismuth liquid metal ion source for focussed ion beam micromachining application  

International Nuclear Information System (INIS)

Liquid metal ion sources (LMISs) with Ga as ion species are widely used in focused ion beam (FIB) technology for micromachining and surface treatment on the sub-micron and nano-scale. Key features of a LMIS for investigating mechanical properties and 3D-microfabrication of materials are long life-time, high brightness, stable ion current and a highly effective milling ability for the material to be modified. In order to increase the material removal rate, heavier ions than Ga and their clusters should be applied. Bismuth (Bi) is the heaviest, non-radio-active element in the periodic table, is non-toxic and exhibits a low melting point. We have thus produced a long-life (about 1000 h) Bi LMIS with a good beam performance, applicable in any FIB system. Since Bi is the only element in this source, it is not necessary to separate it from other ions by a mass filter. Investigation of the sputtering rate of NiTi shape memory alloys using Ga and Bi LMIS showed that, for ...

2008-09-15

454

Kinetic aspects of the photolysis of in-station airborne methyl iodide  

International Nuclear Information System (INIS)

A method for converting organic iodides to elemental iodine would be advantageous in improving the performance of charcoal filters for the removal of radio iodines from reactor off gases. A photochemical method has been developed. The HAVCHM code was used to establish the relevant process time scales on a complete set of rate equations describing the primary and secondary reactions occurring in a plug-flow reactor containing low levels of elemental iodine and methyl iodide in air, which is irradiated by intense u.v. light. These simulations were used to justify the contraction of the complete set of reactions to the most significant elementary processes. The contracted set of rate equations are then solved analytically to render the concentration-time profiles of methyl iodide, total inorganic iodine and total oxidized organics, consistent with the achievement of a desirable radioiodine decontamination factor. For the short contact times available, the flux of ...

455

Is the Supernova Remnant RX J1713.7-3946 a Hadronic Cosmic Ray Accelerator ?  

CERN Document Server

The non-thermal supernova remnant RX J1713.7-3946 (G347.3-0.5) has recently been shown to be a site of cosmic ray (CR) electron acceleration to TeV energies (Muraishi et al. 2000). Here we present evidence that this remnant is also accelerating CR nuclei. Such nuclei can interact with ambient interstellar gas to produce high energy gamma-rays via the decay of neutral pions. We associate the unidentified EGRET GeV gamma- ray source 3EG J1714-3857 with a massive (~3*10 5 Mo) and dense (~500 nucleons cm -3) molecular cloud interacting with RX J1713.7-3946. Direct evidence for such interaction is provided by observations of the lowest two rotational transitions of CO in the cloud; as in other clear cases of interaction, the CO(J=2-1)/CO(J=1-0) ratio is significantly enhanced. Since the cloud is of low radio and X-ray brightness, CR electrons cannot be responsible for the bulk of its GeV emission there. A picture thus emerges where both electrons and nuclei are being ...

2001-01-01

456

Integrated plasma synthesis of efficient catalytic nanostructures for fuel cell electrodes  

International Nuclear Information System (INIS)

A single plasma process involving three consecutive steps has been developed for producing high gas flow catalytic nanostructures on the electrodes of proton exchange membrane (PEM) fuel cells (FC). Using a high density helicon radio frequency (13.56 MHz) plasma, nickel is sputtered onto a porous carbon support. Changing the background gas from argon to methane/hydrogen allowed 2 ?m long, 37 nm diameter carbon nanofibres (CNFs) to be grown by diffusion through the nickel clusters in a 'tip growth' mechanism at the relatively low temperature of 400 deg. C. The third step involves plasma sputtering of platinum onto the CNFs, resulting in nanoclusters (3-8 nm) being formed on the periphery of the CNFs. Four FC cathodes were synthesized on carbon paper and PTFE/carbon loaded cloth (known as gas diffusion layer, GDL), both with and without CNFs, with the Pt/CNFs nanostructures grown on PTFE/carbon loaded cloth having the best FC performances. Compared with conventional ...

2007-08-01

457

Instrumentation and Controls Division progress report, September 1, 1980-July 1, 1982  

Energy Technology Data Exchange (ETDEWEB)

Activities are reported by the Reactor Systems Section, Research Instrument Section, and the Measurement and Controls Engineering Section. Reactor system activities include dynamic analysis, survillanc and diagnostic methods, design and evaluation, detectors, facilities support, process instrumentation development, and special assignments. Activities in the Research Instrument Section include the Navy-ORNL RADIAC development program, advanced ..gamma.. and x ray detector systems, neutron detection and subcriticality measurements, circuit development, position-sensitive detectors, stand-alone computers, environmental monitoring-detectors and systems, plant security, engineering support for fusion energy division, engineering support for accelerator physics, and communications: radio, closed-circuit tv, and computer. Activities in the Measurement and Controls Engineering Section include the AVLIS program; gas centrifuge enrichment technology support; Advanced ...

1982-12-01

458

Industrial applications of the Jefferson Lab high-power free-electron laser  

International Nuclear Information System (INIS)

In partnership with the US Navy, high-technology corporations, and research universities, Jefferson Lab is building a superconducting radio-frequency (SRF) accelerator-driven free-electron laser (FEL) and is outfitting an FEL user facility. This first fourth-generation light source - a 1 kW, 3 #mu#m infrared (IR) laser - is the first step in a program to develop high-average-power SRF-based IR and ultraviolet (UV) FELs for multiple manufacturing applications as well as for defense-related applied research and basic scientific research. This initial FEL will be driven by a 42 MeV, 5 m A recirculating SRF linac similar to the much larger SRF linac in Jefferson Lab's 4 GeV, 200 #mu#A Continuous Electron Beam Accelerator Facility (CEBAF). The FEL is expected to demonstrate 75% energy recovery. Its linac will be cooled by the existing CEBAF cryogenic system. At Jefferson Lab, an infrastructure of facilities and people already supports the advance of SRF and closely ...

1998-09-02

459

IN VACUUM UNDULATOR TASK FORCE REPORT  

Energy Technology Data Exchange (ETDEWEB)

The Green-Chasman lattice, which is the basis for both NSLS storage rings, was conceived with insertion devices in mind. Long, field-free straight sections were provided in the design. The electron optics were chosen so that these sections had zero dispersion and the effects of new magnetic structures placed in these regions would have minimal effect on the emittance of the electron beam. This design concept has been followed by all high-brightness rings which were built subsequent to the NSLS. The X-Ray Ring straight sections also have a very small vertical {beta} function, in addition to the zero dispersion. This was done to optimize the brightness of wiggler sources. There is a further benefit however. The {beta} function determines the beam size and divergence at a particular point in the storage ring lattice. The size is proportional to {radical}{beta} and the divergence is proportional to 1/{radical}{beta}. Thus the electron beam is very small at the center of the X-Ray Ring ...

1998-06-01

460

Gravitational waves interferometer and the VIRGO project  

CERN Document Server

Radio, optical and X-rays telescopes are improving our knowledge of deep space. All these telescopes detect electromagnetic radiation at various frequencies. But a different kind of radiation is generated in the deeper space; it is the gravitational one. Gravitational waves change the space-time metric. As a consequence, GW telescopes should detect an extremely small strain (h < 10/sup -21/) of the geometry of a reference frame; if the frame has a reference dimension (L) of some kilometers, the deformation amplitude ( Delta L = h * L) is limited to 10/sup -16/ meters. Laser interferometers are the most suitable devices to make precise measurements of distances. Their resolution is limited by the laser wavelength ( lambda = 10/sup -6/ meters) and by the light wave-shift detection capability ( Delta Phi = 1 ppb). These theoretical limits are strongly degraded by different noise sources, which reduce the actual resolution by several orders of magnitude. Applied ...

2002-01-01

461

FDTD analysis of body-core temperature elevation in children and adults for whole-body exposure  

Energy Technology Data Exchange (ETDEWEB)

The temperature elevations in anatomically based human phantoms of an adult and a 3-year-old child were calculated for radio-frequency whole-body exposure. Thermoregulation in children, however, has not yet been clarified. In the present study, we developed a computational thermal model of a child that is reasonable for simulating body-core temperature elevation. Comparison of measured and simulated temperatures revealed thermoregulation in children to be similar to that of adults. Based on this finding, we calculated the body-core temperature elevation in a 3-year-old child and an adult for plane-wave exposure at the basic restriction in the international guidelines. The body-core temperature elevation in the 3-year-old child phantom was 0.03 deg. C at a whole-body-averaged specific absorption rate of 0.08 W kg{sup -1}, which was 35% smaller than in the adult female. This difference is attributed to the child's higher body surface area-to-mass ratio.

2008-09-21

462

Extended Gas in Seyfert Galaxies Near Infrared Observations of NGC 2110 and Circinus  

CERN Document Server

We present results of near--IR long-slit spectroscopy in the J and K bands of the Seyfert 2 galaxies NGC 2110 and Circinus, investigating the gaseous distribution, excitation, reddening and kinematics. In NGC 2110, the emission line ratio [FeII]/Pa beta increases towards the nucleus (to ~ 7). The nuclear [Fe II]1.257 (microns) and Pa beta lines are broader (FWHM ~ 500 km/s) than the H2 (2.121) line (FWHM ~ 300 km/s). Both these results suggest that shocks, driven by the radio jet, are an important source of excitation of [Fe II]. The H2 excitation appears to be dominated by X-rays from the nucleus. In Circinus, both [FeII]/Pa beta and H2/Br gamma decrease from ~ 2 at 4 arcsec from the nucleus to nuclear values of ~ 0.6 and ~ 1, respectively, suggesting that the starburst dominates the nuclear excitation, while the AGN dominates the excitation further out (r > 2 arcsec). For both galaxies, the gaseous kinematics are consistent with circular rotation in the plane ...

1998-01-01

463

Experimental determination of the dosimetric characteristics for the I-Plant"T"M model 3600 "1"2"5I brachytherapy source  

International Nuclear Information System (INIS)

The dosimetric characteristics for a new brachytherapy seed source (I-Plant"T"M model 3600) were measured using LiF thermoluminescent dosimeters and appropriate phantom materials in conformance with the methodology and guidance provided by the AAPM Task Group 43. The I-Plant"T"M model 3600 is the successor to the I-Plant"T"M model 3500. The major difference between these sources is that the model 3600 contains a leaded-glass core to provide radio-opacity (while the model 3500 contains a silver core), which does not produce spectral contamination upon neutron activation. The dose rate constant #LAMBDA# for the model 3600 was determined to be 1.00 Gy h"-"1 U"-"1 (with a 6% overall relative standard deviation), compared to 1.01 cGy h"-"1 U"-"1 reported for the model 3500 in previous studies. The remaining dosimetric characteristics also are similar for both sources.

2005-06-01

464

Enhancement of surface properties of 45{number_sign} steel using plasma immersion ion implantation  

Energy Technology Data Exchange (ETDEWEB)

45{number_sign} steel, which has good mechanical strength and is relatively cheap, is a common constituent in industrial components, such as precision gears, piston columns of oil pumps, and so on. However, since the working environment of these industrial parts is sometimes quite harsh and unforgiving, they are vulnerable to wear and corrosion. Replacing 45{number_sign} steel with stainless or alloy steel increases the cost significant, and a better alternative is to improve its surface properties and lifetime using plasma immersion ion implantation (PIII). The authors have devised a variety of treatment processes using PIII, including radio-frequency (RF) plasma nitriding, RF plasma nitriding and nitrogen PIII, Ti deposition in conjunction with nitrogen PIII (IBED), as well as Cr deposition followed by nitrogen PIII (IBED). To assess the efficacy of the processes, the microhardness and mass loss due to wear were measured for both the untreated and treated ...

1997-12-31

465

Electromagnetic radiation unmasked  

International Nuclear Information System (INIS)

This article describes the nature of the electromagnetic waves, what they are and how do they affect us. Current concern is focused on exposure to low level power-frequency magnetic fields like microwave radiation from mobile phones and leaking microwave ovens; high power radiation from defence and airport radars; fields close to high voltage transmission lines; radio frequency fields from industrial welders and heaters and DC magnetic fields in aluminium smelters. These fields with frequency less than 300 GHz do not carry sufficient energy to break chemical bonds and it is assumed that they cannot damage cell DNA. The amount of radiation absorbed by a human exposed to far field electromagnetic radiation (EMR) depends on the orientation and size of the person. In the 30-300 MHz range it is possible to excite resonance in the whole or partial body such as the head. It is emphasised that since there are some evidence that electromagnetic fields do harm, a policy of ...

1996-01-01

466

Difference Antenna Selection and Power Allocation for Wireless Cognitive Systems  

CERN Document Server

In this paper, we propose an antenna selection method in a wireless cognitive radio (CR) system, namely difference selection, whereby a single transmit antenna is selected at the secondary transmitter out of $M$ possible antennas such that the weighted difference between the channel gains of the data link and the interference link is maximized. We analyze mutual information and outage probability of the secondary transmission in a CR system with difference antenna selection, and propose a method of optimizing these performance metrics of the secondary data link subject to practical constraints on the peak secondary transmit power and the average interference power as seen by the primary receiver. The optimization is performed over two parameters: the peak secondary transmit power and the difference selection weight $\\delta\\in [0, 1]$. We show that, difference selection using the optimized parameters determined by the proposed method can be, in many cases of ...

2010-01-01

467

Development of swing-free / shock free crane  

Energy Technology Data Exchange (ETDEWEB)

To develop the automatized crane and to apply the relevant technology to nuclear power plants, in this project and automatized crane control system is developed along with a swing and shock crane. Also, this technology has been transferred to Bando Machinery Co. Ltd. The drive mechanism of crane is designed by adopting vector drives which provide soft acceleration and deceleration characteristics. Also, radio modems and a long-range laser displacement sensor which are commercially available are introduced to accommodate the large scaled crane systems. Also, several devices are developed for the automation of crane system. These are a crane controller, a supervisory controller, a angle measuring device, and laser localizer, a drum grapple device, and crane supervisory program. The performance of developed crane system is revealed to rapidly reduce the residual swingof the transported object and precisely controls the object position in any case. Also, the laser ...

1999-04-01

468

Computational AstroStatistics Fast and Efficient Tools for Analysing Huge Astronomical Data Sources  

CERN Document Server

I present here a review of past and present multi-disciplinary research of the Pittsburgh Computational AstroStatistics (PiCA) group. This group is dedicated to developing fast and efficient statistical algorithms for analysing huge astronomical data sources. I begin with a short review of multi-resolutional kd-trees which are the building blocks for many of our algorithms. For example, quick range queries and fast n-point correlation functions. I will present new results from the use of Mixture Models (Connolly et al. 2000) in density estimation of multi-color data from the Sloan Digital Sky Survey (SDSS). Specifically, the selection of quasars and the automated identification of X-ray sources. I will also present a brief overview of the False Discovery Rate (FDR) procedure (Miller et al. 2001a) and show how it has been used in the detection of ``Baryon Wiggles'' in the local galaxy power spectrum and source identification in radio data. Finally, I will look ...

2001-01-01

469

Collisional cooling of negative-ion beams  

Energy Technology Data Exchange (ETDEWEB)

Studies have been conducted to determine the feasibility of using collisional cooling for reducing emittances and energy spreads in negative-ion beams to levels commensurate with effective isobaric purification with conventional high-resolution electromagnetic isobar separators as required for use at the Holifield Radioactive Ion Beam Facility (HRIBF). We have designed a gas-filled radio frequency quadrupole ion cooler equipped with provisions for retarding energetic negative-ion beams to energies below thresholds for electron detachment at injection and for re-acceleration to initial energies after the cooling process. The device has been used to cool several ion beams with initial energy spreads, {delta}E>10 eV to final energy spreads, {delta}E{approx}2 eV FWHM, including O{sup -} and F{sup -}. Overall transmission efficiencies of {approx}14% for F{sup -} beams have been obtained. Experimental results show that electron detachment is the major loss ...

2002-01-01

470

CZT vs FFT: Flexibility vs Speed  

Energy Technology Data Exchange (ETDEWEB)

Bluestein's Fast Fourier Transform (FFT), commonly called the Chirp-Z Transform (CZT), is a little-known algorithm that offers engineers a high-resolution FFT combined with the ability to specify bandwidth. In the field of digital signal processing, engineers are always challenged to detect tones, frequencies, signatures, or some telltale sign that signifies a condition that must be indicated, ignored, or controlled. One of these challenges is to detect specific frequencies, for instance when looking for tones from telephones or detecting 60-Hz noise on power lines. The Goertzel algorithm described in Embedded Systems Programming, September 2002, offered a powerful tool toward finding specific frequencies faster than the FFT.Another challenge involves analyzing a range of frequencies, such as recording frequency response measurements, matching voice patterns, or displaying spectrum information on the face of an amateur radio. To meet this challenge most ...

2003-10-01

471

Behavior of the positron beam of the Super-ACO storage ring in response to a modification of the RF frequency for free-electron laser experiments  

International Nuclear Information System (INIS)

The macrotemporal structure of the Super-ACO Storage ring free-electron laser (FEL) can be either continuous, pulsed, or chaotic, and can present some rapid fluctuations. The temporal evolution of a storage ring FEL involves both the longitudinal motion of the positron beam (especially the synchrotron oscillations) and the FEL dynamics, as in a coupled system. Studies on the dynamics of the positron beam are performed here, in the goal to have a stable source for FEL applications, and to determine the conditions for a stable Q-switching experiment. The employed method is to study the influence of a controlled change of the radio frequency (RF) (modulation or frequency jump) on the beam. A simple theoretical model taking into account the perturbed RF system is presented to help the understanding of the experimental data. The different methods of measurement are described. Then, the results are given for several experimental conditions and the influence of different ...

472

Are HI Supershells the Remnants of $\\gamma$-Ray Bursts?  

CERN Document Server

Gamma-Ray Bursts (GRBs) are thought to originate at cosmological distances from the most powerful explosions in the Universe. If GRBs are not beamed then the distribution of their number as a function of gamma-ray flux implies that they occur once per (0.3-40) million years per bright galaxy and that they deposit >10^{53} ergs into their surrounding interstellar medium. The blast wave generated by a GRB explosion would be washed out by interstellar turbulence only after tens of millions of years when it finally slows down to a velocity of 10 km/s. This rather long lifetime implies that there could be up to several tens of active GRB remnants in each galaxy at any given time. For many years, radio observations have revealed the enigmatic presence of expanding neutral-hydrogen (HI) supershells of kpc radius in the Milky Way and in other nearby galaxies. The properties of some supershells cannot be easily explained in terms of conventional sources such as stellar ...

1998-01-01

473

Adaptive and mobile ground sensor array.  

Energy Technology Data Exchange (ETDEWEB)

The goal of this LDRD was to demonstrate the use of robotic vehicles for deploying and autonomously reconfiguring seismic and acoustic sensor arrays with high (centimeter) accuracy to obtain enhancement of our capability to locate and characterize remote targets. The capability to accurately place sensors and then retrieve and reconfigure them allows sensors to be placed in phased arrays in an initial monitoring configuration and then to be reconfigured in an array tuned to the specific frequencies and directions of the selected target. This report reviews the findings and accomplishments achieved during this three-year project. This project successfully demonstrated autonomous deployment and retrieval of a payload package with an accuracy of a few centimeters using differential global positioning system (GPS) signals. It developed an autonomous, multisensor, temporally aligned, radio-frequency communication and signal processing capability, and an array ...

2003-12-01

474

AGN Feedback: Does it work?  

CERN Document Server

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

2009-01-01

475

A study on the real-time radiation dosimetry measurement system based on optically stimulated luminescence  

Science.gov (United States)

The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity. Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-access and hazardous. In addition, optical fiber dosimeters are immune to electrical and radio-frequency interference. In this paper, a novel remote optical fiber radiation dosimeter is described. The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL. The measuring range of the dosimeter is from 0.1 to 100 Gy. The equipment is relatively simple and small in size, and has low power consumption. This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions. Supported by National Natural Science Foundation of China (10475112), Western Light Foundation of Chinese ...

2008-05-01

476

A rapid, radiometric assay for sucrose synthase  

Energy Technology Data Exchange (ETDEWEB)

Investigations of sucrose synthase in maize root tips have required development of a means to circumvent the rapid decline of activity observed after extraction dialysis and either synthetic or degradative assays. Several protease inhibitors were tested; although PMSF increased initial activity, no inhibitor prevented the drop in activity with time. Western blot analysis indicated that activity decline was not associated with protein degradation. Therefore, a procedure was developed which (1) shortened extraction-to-assay period from ca. 24 hours to 7 minutes, (2) simplified previous assays and (3) reduced the amount of tissue required. Extract was desalted with spun columns and the {sup 14}C-UDPG product recovered with DEAE ion exchange paper. The minute quantities of product recovered can be concealed by the presence of trace impurities in the {sup 14}C-sucrose utilized. DEAE ion exchange paper was used to remove interfering radio-labelled compounds from the {sup ...

1990-05-01

477

A Remarkable Low-Mass X-ray Binary within 0.1 pc of the Galactic Center  

CERN Document Server

Recent X-ray and radio observations have identified a transient low-mass X-ray binary (LMXB) located only 0.1 pc in projection from the Galactic center, CXOGC J174540.0-290031. In this paper, we report the detailed analysis of X-ray and infrared observations of the transient and its surroundings. Chandra bservations detect the source at a flux of F_X = 2e-12 erg cm^-2 s^-1 (2-8 keV). After accounting for absorption both in the interstellar medium and in material local to the source, the implied luminosity of the source is only L_X = 4e34 erg/s (2-8 keV; D=8 kpc). However, the diffuse X-ray emission near the source also brightened by a factor of 2. The enhanced diffuse X-ray emission lies on top of a known ridge of dust and ionized gas that is visible infrared images. We interpret the X-ray emission as scattered flux from the outburst, and determine that the peak luminosity of CXOGC J174540.0-290031 was >2e36 erg/s. We suggest that the relatively small observed ...

2005-01-01

478

A Plan to Diffuse Instructional Materials for Use by Transportation Educators.  

Science.gov (United States)

A plan to diffuse instructional modules for the preparation of transportation professionals is presented, based on research and demonstration projects sponsored by the Urban Mass Transportation Administration (UMTA). The diffusion/adoption plan involves: developing instructional modules; disseminating the modules to professors teaching transportation courses at the college level; promoting the use and adoption of the modules; and evaluating and revising the plan. Transportation educators teach in a variety of disciplines (e.g., engineering, public administration, urban planning, and technology). Eight design and evaluation criteria for the instructional modules are listed, along with the procedures used by West Virginia University in developing the five instructional modules. The diffusion strategy involves repackaging UMTA research findings, change agents, and the use of information channels (e.g, television/radio, periodicals, direct mail). Adoption tactics ...

1986-01-01

479

A Cognitive Approach to Network Monitoring in Heterogeneous Environments  

DEFF Research Database (Denmark)

Introducing intelligence by means of cognition for managing, protecting, processing, and delivering of information in mobile communication systems is the way towards ubiquitous, converged and secure communications. In this context, this paper introduces the concept of quality of information (QoI). QoI means QoS while all the requirements for dependability, security, privacy and trust are satisfied at the highest possible level. This work proposes and describes an approach to network monitoring in a heterogeneous communication environment based on use of cognitive techniques and learning predictive algorithms (e.g., fuzzy logic). These methodologies are used to create an autonomy in the decision making process that is based on the calculation of key performance indicators (KPIs), which in their turn would trigger the needed radio resource management algorithms. The expected output is an improved network performance in terms of maximized throughput and faster ...

2007-01-01

480

Simulations of the Microwave Sky  

Energy Technology Data Exchange (ETDEWEB)

We create realistic, full-sky, half-arcminute resolution simulations of the microwave sky matched to the most recent astrophysical observations. The primary purpose of these simulations is to test the data reduction pipeline for the Atacama Cosmology Telescope (ACT) experiment; however, we have widened the frequency coverage beyond the ACT bands and utilized the easily accessible HEALPix map format to make these simulations applicable to other current and near future microwave background experiments. Some of the novel features of these simulations are that the radio and infrared galaxy populations are correlated with the galaxy cluster and group populations, the primordial microwave background is lensed by the dark matter structure in the simulation via a ray-tracing code, the contribution to the thermal and kinetic Sunyaev-Zel'dovich (SZ) signals from galaxy clusters, groups, and the intergalactic medium has been included, and the gas prescription to ...

2009-12-16

481

High-power radio frequency pulse generation and extraction based on wakefield excited by an intense charged particle beam in dielectric-loaded waveguides  

International Nuclear Information System (INIS)

Power extraction using a dielectric-loaded (DL) waveguide is a way to generate high-power radio frequency (RF) waves for future particle accelerators, especially for two-beam-acceleration. In a two-beam-acceleration scheme, a low-energy, high-current particle beam is passed through a deceleration section of waveguide (decelerator), where the power from the beam is partially transferred to trailing electromagnetic waves (wakefields); then with a properly designed RF output coupler, the power generated in the decelerator is extracted to an output waveguide, where finally the power can be transmitted and used to accelerate another usually high-energy low-current beam. The decelerator, together with the RF output coupler, is called a power extractor. At Argonne Wakefield Accelerator (AWA), we designed a 7.8GHz power extractor with a circular DL waveguide and tested it with single electron bunches and bunch trains. The output RF frequency (7.8GHz) is the sixth harmonic ...

482

A.C.R.O. activity report 2003; A.C.R.O. rapport d'activite 2003  

Energy Technology Data Exchange (ETDEWEB)

A.C.R.O. (Association pour le Controle de la Radioactivite dans l'Ouest) is a French non governmental organisation that operates a laboratory for radioactivity analysis. It was created in 1986 as a response to people demands for information and reliable, independent testing. The organisation mainly carries out missions of information and training for its correspondents and more generally for a wide audience, particularly for people who worry about problems of environment, health, management of radioactive waste and emissions. Thanks to its structure, it enables citizens to involve themselves together with scientists so as to gain access to information that was hither to reserved to specialists. The organisation can vouchsafe its independence from the diversity of its members and volunteers, as well as from the diversity of its money resources. Besides its headquarters situated on the city of Caen area (Normandy), three branches situated in North Normandy, in Touraine and North ...

2003-07-01

483

Final technical report for ''Frontiers in Plasma Kinetic Theory''  

International Nuclear Information System (INIS)

This report summarizes the results and activities funded by this three-year award. The principal goal of this project was to determine the thermal conductivity in clusters of galaxies. Intracluster plasmas possess chaotic magnetic fields. Since charged particles are constrained to move primarily along magnetic field lines, the topology of intracluster magnetic fields slows particle diffusion relative to the non-magnetized case, thereby reducing the thermal conductivity. Our first approach to this problem was to employ the static-magnetic-field approximation. In reality, intracluster magnetic field lines are constantly moving, since they are advected by turbulent intracluster motions. The turbulent velocities, however, are much smaller than the rapid speeds of thermal electrons, which make the dominant contribution to the thermal conductivity. In the static-field approximation, one neglects turbulent motions of field lines, and calculates the diffusion coefficient of thermal electrons ...

2007-02-01

484

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2000 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 2000 annual report covers the fourth year of sampling of this multi-year study. In 2000 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon rivers. The Snake River was sampled between Lower Granite Dam (rkm 174) and the mouth of the Salmon River (rkm 303), and the Salmon River was sampled from its mouth upstream to Hammer Creek (rkm 84). A total of 53,277 hours of setline effort and 630 hours of hook-and-line effort was employed in 2000. A total of 538 white sturgeon were captured and tagged in the Snake River and 25 in the Salmon River. Since 1997, 32.8 percent of the tagged white sturgeon have been ...

2003-03-01

485

Evaluate Potenial Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2002 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This report presents a summary of results from the 1997-2002 Phase II data collection and represents the end of phase II. From 1997 to 2001 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon. A total of 1,785 white sturgeon were captured and tagged in the Snake River and 77 in the Salmon River. Since 1997, 25.8 percent of the tagged white sturgeon have been recaptured. Relative density of white sturgeon was highest in the free-flowing segment of the Snake River, with reduced densities of fish in Lower Granite Reservoir, and low densities the Salmon River. Differences were detected in the length frequency ...

2004-02-01

486

A.C.R.O. activity report 2002; A.C.R.O. rapport d'activite 2002  

Energy Technology Data Exchange (ETDEWEB)

A.C.R.O. (Association pour le Controle de la Radioactivite dans l Ouest) is a French non governmental organisation that operates a laboratory for radioactivity analysis. It was created in 1986 as a response to people demands for information and reliable, independent testing. The organisation mainly carries out missions of information and training for its correspondents and more generally for a wide audience, particularly for people who worry about problems of environment, health, management of radioactive waste and emissions. Thanks to its structure, it enables citizens to involve themselves together with scientists so as to gain access to information that was hither to reserved to specialists. The organisation can vouchsafe its independence from the diversity of its members and volunteers, as well as from the diversity of its money resources. Besides its headquarters situated on the city of Caen area (Normandy), three branches situated in North Normandy, in Touraine and North Cotentin ...

2002-07-01

487

Wilsonville Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Wilsonville ACL R and D Facility material balance procedure. Topical Report No. 11  

Science.gov (United States)

Prior to 1978, the Wilsonville Advanced Coal Liquefaction facility material balance surrounded only the thermal liquefaction unit and involved analyses of only the slurry stream and individual gas streams. The distillate solvent yield was determined by difference. Subsequently, several modifications and additional process units were introduced to this single unit system. With the inclusion of the deashing unit in 1978 and the catalytic hydrogenation unit in 1981, the process has evolved into a sophisticated two-stage coal liquefaction process and has the potential for various modes of integration. This report presents an elemental balancing procedure and a simplified presentation format that is sufficiently flexible to meet current and future needs. The development of the elemental balancing technique and the relevant computer programs to handle the calculations have been addressed. This will be useful in modelling individual unit performance as well as determining ...

1984-09-01

488

Understanding profitability: Why some customers are hot and others are not  

Energy Technology Data Exchange (ETDEWEB)

Gone are the days when utilities would boast how many new customers were being added to their system annually-regardless of whether they were in fact profitable to serve or not-as if bigger was always better. In a not too distant future, and with the liberalization of the business environment, some utilities may no longer wish to serve certain customers on their systems, while at the same time aggressively wooing other customers. With the anticipated arrival of competition and erosion of utility franchise service areas, the electric power industry will gradually evolve into a mode where customers will be segmented into finer groups and evaluated based on their expected profit margins-theoretically the difference between the revenues expected from them and the cost of serving them. Understanding this basic concept, and the mastery of the art of arriving at the correct profit margin for each market segment, will be essential to overall business profitability and ...

1996-03-01

489

Unbundling services in a competitive electricity market  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this presentation is to provide an in-depth discussion of the possible evolution of unbundling of services in a competitive environment. The author discusses unbundling from both a technical/engineering and an economic perspective. The main thrust of the talk is threefold: (a) that in the long run the potential for unbundling of services is extremely large from an engineering perspective; (b) that the form of the initial industry structure will have an important impact on the extent of service unbundling; and (c) that unbundling of wholesale related services is where most of the initial demand will be. (A) Engineering Perspectives on Unbundling: A large proportion of ancillary services can be provided in a competitive framework with current technologies. The author discusses those that current technologies may not facilitate such a decentralized approach. (B) The relation between unbundling and industry structure: Not all industry structures provide the same incentives ...

1996-03-01

490

Transient enhanced diffusion of dopants in preamorphized Si layers  

Energy Technology Data Exchange (ETDEWEB)

Transient Enhanced Diffusion (TED) of dopants in Si is the consequence of the evolution, upon annealing, of a large supersaturation of Si self-interstitial atoms left after ion bombardment. In the case of amorphizing implants, this supersaturation is located just beneath the c/a interface and evolves through the nucleation and growth of End-Of-Range (EOR) defects. For this reason, the authors discuss here the relation between TED and EOR defects. Modelling of the behavior of these defects upon annealing allows one to understand why and how they affect dopant diffusion. This is possible through the development of the Ostwald ripening theory applied to extrinsic dislocation loops. This theory is shown to be readily able to quantitatively describe the evolution of the defect population (density, size) upon annealing and gives access to the variations of the mean supersaturation of Si self-interstitial atoms between the loops and responsible for TED. This initial ...

1997-11-01

491

Total interaction cross sections and effective atomic numbers of some biologically important compounds containing H, C, N and O in the energy range 6.4-136 keV  

International Nuclear Information System (INIS)

The total interaction cross sections (#sigma#_t) of some sugars and amino acids and five elements: lithium, carbon, oxygen, aluminium and calcium have been measured for 6.4 keV, 13.95 keV, 14.4 keV, 17.74 keV, 24.14 keV, 30.8 keV, 35 keV, 59.54 keV, 81 keV, 122 keV and 136 keV photons in a narrow beam good geometry set up, by using high resolution detectors such as a Si-PIN diode detector and a high purity germanium detector. The #sigma#_t values have been used in a matrix method to evaluate the effective atomic numbers Z_e_f_f of the samples from their effective atomic cross sections #sigma#_a. The effective atomic cross section of a sample #sigma#_a is the total interaction cross section divided by the total number of atoms of all types in it. Further, a quantity called the effective atomic weight A_e_f_f of a sample was defined as the ratio of the molecular weight A to the total number of atoms of all types in it. The variation of Z_e_f_f was systematically studied with respect to ...

2007-09-28

492

Taking transport to a higher plane  

Energy Technology Data Exchange (ETDEWEB)

The coal transportation industry has played an integral role in determining coal markets, particularly in recent years, as the industry has evolved from cost-based pricing to market-based pricing. Aggressive pricing by Western rail carriers has caused extensive changes in coal marketing patterns in the Midwest. Multi-modal barge deliveries of Western and Appalachian coals have also played a significant, though lesser, role in changing coal markets. Eastern rail carriers have generally lagged in their aggressive pursuit of new coal markets and, to date, few changes in coal markets have been realised. The historic dominant role of transportation in shaping markets for coal will continue into the future as the utility industry contends with the effects of CAAA compliance and deregulation and as the coal industry contends with regional coal displacements and major imbalances in supply and demand. The dominance of rail transportation in defining coal distribution ...

1994-04-01

493

Revisit to the helicity and the generalized self-organization theory  

Energy Technology Data Exchange (ETDEWEB)

It is clarified that the so-caned 'helicity conservation law' is never the conservation equation of the helicity K itself', but is merely 'the time change rate equation of K', which is passively and resultantly determined by the mutually independent volume and surface integral terms. It is shown that since the total helicity K can never be conserved in the real experimental systems, the conjecture of the total helicity invariance is not physically available to real magnetized plasmas in an exact sense. The well-known relaxation theory by Dr. J. B. Taylor is clarified to be neither the variational principle nor the energy principle, but be merely a mathematical calculation, using the variational calculus in order to find the minimum magnetic energy solution from the set of solutions having the same value of K. With the use of auto-correlations for physical quantities, it is presented that a novel basic formulation of an extended generalized ...

2000-09-01

494

RED NUGGETS AT z #approx# 1.5: COMPACT PASSIVE GALAXIES AND THE FORMATION OF THE KORMENDY RELATION  

International Nuclear Information System (INIS)

We present the results of Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) imaging of a sample of 19 high-mass passively evolving galaxies with 1.2 < z < 2, taken primarily from the Gemini Deep Deep Survey (GDDS). Around 80% of galaxies in our GDDS sample have spectra dominated by stars with ages #approx#>1 Gyr. Our rest-frame R-band images show that most of these objects have compact regular morphologies which follow the classical R "1"/"4 law. These galaxies scatter along a tight sequence in the size versus surface brightness parameter space which defines the Kormendy relation. Around one-third (3/10) of the massive red objects in the GDDS sample are extraordinarily compact, with effective radii under 1 kpc. Our NICMOS observations allow the detection of such systems more robustly than is possible with optical (rest-frame UV) data, and while similar systems have been seen at z #approx#> 2, this is the first time such systems have been ...

2009-04-10

495

Morphological survey of bar, lens, and ring components in galaxies: Secular evolution in galaxy structure  

International Nuclear Information System (INIS)

A morphological survey of barred galaxies is made to investigate the frequency of occurrence, nature, and size distributions of bars, lenses, inner and outer rings, and global spiral structure. The 121 brightest available barred galaxies are examined on Sky Survey copy plates, and on deeper and larger-scale plates, with the following main results.1. Lenses and inner rings are components of major importance in barred galaxies, occurring, respectively, in 54% of SBO--SBa, and 76% of SBab--SBc galaxies. Few early-type galaxies have rings; almost no late-type ones have lenses.2. There is an intimate connection between bars and lenses: in 17 of 20 galaxies with both components, the bar exactly fills the lens in one dimension.3. We suggest that lenses originate as bars, through an unknown process which makes some bars evolve away to a nearly axisymmetric state. Several properties of the proposed process are deduced. We emphasize the possible importance of internal ...

496

LANL environmental restoration site ranking system: System description. Final report  

Energy Technology Data Exchange (ETDEWEB)

The basic structure of the LANL Environmental Restoration (ER) Site Ranking System and its use are described in this document. A related document, Instructions for Generating Inputs for the LANL ER Site Ranking System, contains detailed descriptions of the methods by which necessary inputs for the system will be generated. LANL has long recognized the need to provide a consistent basis for comparing the risks and other adverse consequences associated with the various waste problems at the Lab. The LANL ER Site Ranking System is being developed to help address this need. The specific purpose of the system is to help improve, defend, and explain prioritization decisions at the Potential Release Site (PRS) and Operable Unit (OU) level. The precise relationship of the Site Ranking System to the planning and overall budget processes is yet to be determined, as the system is still evolving. Generally speaking, the Site Ranking System will be used as a decision aid. That ...

1992-10-13

497

Galactic evolution of D and "3He including stellar production of "3He  

International Nuclear Information System (INIS)

New stellar models which track the production and destruction of "3He (and D) have been evolved for a range of stellar masses (0.65#<=#M/M_c_i_r_c_l_e_-_d_o_t#<=#100), metallicities (0.01#<=#Z/Z_c_i_r_c_l_e_-_d_o_t#<=#1), and initial (main-sequence) "3He mass fractions (10"-"5#<=#X_3_,_M_S#<=#10"-"3). Armed with the "3He yields from these stellar models we have followed the evolution of D and "3He using a variety of chemical evolution models with and without infall of primordial or processed material. Production of new "3He by the lower mass stars overwhelms any reasonable primordial contributions and leads to predicted abundances in the presolar nebula and/or the present interstellar medium in excess of the observationally inferred values. This result, which obtains even for zero primordial D and "3He, and was anticipated by Rood, Steigman, ampersand Tinsley is insensitive to the choice of chemical evolution model; it is driven by the large "3He ...

498

Enterprise energy management : Part 1  

Energy Technology Data Exchange (ETDEWEB)

The needs of large industrial, commercial, and institutional energy consumers are more closely connected with the needs of power utilities and energy services companies, a result of the evolving global energy environment. Consumer choice, competition amongst energy suppliers, and increased demand are brought about in some regions by deregulation. Increasingly, large energy consumers expect high levels of quality and reliability from the energy delivered. As a result, management of the cost and the quality of the energy product and the energy assets that produce, deliver, control and consume it requires different strategies. Three major challenges must be overcome: (1) requirement to support economic and efficient delivery, purchasing and use of energy, (2) requirement to guarantee higher levels of power quality and reliability, and (3) requirement to supply the growing demand for energy while establishing a market-based pricing system. The solution is the ...

2001-09-01

499

Effective atomic numbers and electron densities of some biologically important compounds containing H, C, N and O in the energy range 145-1330 keV  

International Nuclear Information System (INIS)

A semi-empirical relation which can be used to determine the total attenuation cross sections of samples containing H, C, N and O in the energy range 145-1332 keV has been derived based on the total attenuation cross sections of several sugars, amino acids and fatty acids. The cross sections have been measured by performing transmission experiments in a narrow beam good geometry set-up by employing a high-resolution hyperpure germanium detector at seven energies of biological importance such as 145.4 keV, 279.2 keV, 514 keV, 661.6 keV, 1115.5 keV, 1173.2 keV and 1332.1 keV. The semi-empirical relation can reproduce the experimental values within 1-2%. The total attenuation cross sections of five elements carbon, aluminium, titanium, copper and zirconium measured in the same experimental set-up at the energies mentioned above have been used in a new matrix method to evaluate the effective atomic numbers and the effective electron densities of samples such as cholesterol, fatty acids, ...

2006-09-28

500

Allocation of risks in a competitive electric market  

Energy Technology Data Exchange (ETDEWEB)

To many, recent developments in electric markets are perplexing. Competition has appeared, often in the form of new players who do not own and operate generation or transmission facilities. Yet, these players happily enter into contracts obliging them to make or take delivery of power at set prices for months or even years into the future. They seem unconcerned about predicted capacity shortages, fuel price uncertainty or unpredictable plant outages. For the most part, these new players understand these risks quite well. They simply believe in the efficacy of markets. Until recently, price ensured recovery of cost. They foresee a true market where price makes supply equal demand and cost is not a factor in the short term at least. The appearance of such players is an augury of the new industry structure, one in which specialists in taking and managing distinct business risks evolve from within or enter from outside. They take and manage price risk in much the same ...

1996-03-01