WorldWideScience
1

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 ...

1996-11-01

2

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 ...

1995-10-01

3

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 ...

1996-04-09

4

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

5

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

7

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

8

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) ...

2010-01-01

9

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

10

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 ...

12

Generators of nonequilibrium low-temperature plasma  

Energy Technology Data Exchange (ETDEWEB)

Results are described of a study and of the characteristics of sources of a non-equilibrium gas-discharge plasma. The plasma generators considered include glow, high frequency, and arc discharge generators. Thermodynamic, ionic, and electronic processes occurring in the plasmas are evaluated.

1988-06-01

13

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

14

ESTIMATION OF WATER QUALITY CRITERIA VIOLATION FREQUENCIES USING PEARSON PERCENTILES  

Science.gov (United States)

A numerical technique is developed for estimating water quality violation frequencies due to pollutant discharges from urban areas during combined sewer overflow events. The first four moments of in-stream pollutant concentration are found by integrating a pollutant loading - wat...

15

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

16

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.

17

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

18

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

19

Development of Plasma Technologies at IPP NSC KIPT  

International Nuclear Information System (INIS)

Plasma Technologies in Institute of Plasma Physics of the NSC KIPT are recently developed in the following directions. Material surfaces modification under their irradiation with pulsed plasma streams of different working gases. Besides traditional analysis of improvements of tribological characteristics and structural-phase changes of the modified layers recently we started investigations of material corrosions characteristic improvement under influence of pulsed plasma on the material surfaces. As to the surface coatings in arc discharges of Bulat type devices, new trends are related with multi-layers coatings, using Ti-AI-N coatings in cutting tools, using high frequency discharges or combined HF- and arc discharges for increasing the nomenclature of goods to be coated. Development of ozonators is respectively new area for IPP NSC KIPT. On the base of barrier high-frequency ...

2001-09-19

20

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 ...

1997-05-01

21

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 ...

1999-04-01

22

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

23

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.

24

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

25

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

26

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

27

Electron density and collision frequency of microwave resonant cavity produced discharges. [Progress report  

Energy Technology Data Exchange (ETDEWEB)

This progress report consists of an article, the abstract of which follows, and apparently the references and vita from a proposal. A review of perturbation diagnostics applied to microwave resonant cavity discharges is presented. The classical microwave perturbation technique examines the shift in the resonant frequency and cavity quality factor of the resonant cavity caused by low electron density discharges. However, modifications presented here allow the analysis to be applied to discharges with electron densities beyond the limit predicted by perturbation theory. An {open_quote}exact{close_quote} perturbation analysis is presented which models the discharge as a separate dielectric, thereby removing the restrictions on electron density imposed by the classical technique. The {open_quote}exact{close_quote} method also uses measurements of the shifts in the resonant conditions of ...

1992-12-31

28

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 ...

2002-07-01

29

Efficiency of ozone production by pulsed positive corona discharge in synthetic air  

International Nuclear Information System (INIS)

We have studied the efficiency of ozone production by pulsed positive corona discharge in coaxial wire-cylinder geometry at atmospheric pressure. A corona discharge was generated by short (#approx#150 ns) high voltage pulses applied between a silver coated copper wire anode and stainless steel cylinder cathode in synthetic air. A pyrex probe and Teflon tube was used for collecting discharge products and an ozone concentration was monitored outside of the discharge chamber by a non-dispersive UV absorption technique. The production of ozone was investigated as a function of energy density (10"-"4-3x10"-"1 Wh l"-"1) delivered to the discharge volume by combining the discharge frequency (0.1-10 Hz) and airflow rate (1-32 l min"-"1). From ozone concentration measurements we have evaluated the ozone production, yield and production energy cost. ...

2002-06-07

30

The influence of contrasting suspended particulate matter transport regimes on the bias and precision of flux estimates  

British Library Electronic Table of Contents (United Kingdom)

A large database (507 station-years) of daily suspended particulate matter (SPM) concentration and discharge data from 36 stations on river basins ranging from 600?km2 to 600,000?km2 in size (USA and Europe) was collected to assess the effects of SPM transport regime on bias and imprecision of flux estimates when using infrequent surveys and the discharge-weighted mean concentration method. By extracting individual SPM concentrations and corresponding discharge values from the database, sampling frequencies from 12 to 200 per year were simulated using Monte Carlo techniques. The resulting estimates of yearly SPM fluxes were compared to reference fluxes derived from the complete database. For each station and given frequency, bias was measured by the median of relative errors between estima...

2006-01-01

31

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

32

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

33

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.).

34

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 ...

2010-01-01

35

Monitoring DC partial discharges with Nilsson Plate  

Energy Technology Data Exchange (ETDEWEB)

The Nilsson Plate High Frequency Adaptation of the Static Electrification Monitor developed by Electric Research and Management, Inc. for EPRI has demonstrated that the Nilsson Plate can be utilized as a practical high frequency antenna to record partial discharge activity within a transformer. Tests in the ABB factory at Muncie, IN on a 650 MVA, 345/20.9 kV, three-phase unit step-up transformer for TU Electric showed the Nilsson plate detecting partial discharge activity. Although this test was the first attempt at using the Nilsson plate in this manner, and in spite of higher than expected electrical noise levels, the data demonstrated that partial discharges can be detected. The tests also demonstrated that corona activity external to the transformer was not recorded by the plate. Some development work needs to be completed to eliminate the noise source from other monitors on the ...

1995-05-01

36

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

37

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

38

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

39

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

40

Detection of EDM defects under Monju support plate using experimental data from remote field eddy current probes and a multi-frequency algorithm  

International Nuclear Information System (INIS)

This paper describes detection of electro-discharged machine (EDM) defects in magnetic steam generator (SG) tubes of Monju fast breeder reactor (FBR). The EDM defects are located under support plate (SP), on the outer tube surface and they are detected by a remote field eddy current probe. Using the experimental measurements and a multi frequency algorithm, the defect signal can be extracted from the SP signal. The parameters of the multi-frequency algorithm were calculated by comparing SP measurements with two-dimensional finite element simulations (FEM). (author)

2006-07-01

41

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 ...

2003-10-01

42

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

43

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

44

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 ...

2006-02-21

45

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 ...

2006-02-21

46

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

47

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

48

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 ...

1999-09-13

49

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

50

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 ...

2003-02-01

51

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 ...

2007-06-04

52

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 ...

2007-06-04

53

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 ...

1996-12-31

54

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 ...

1998-08-01

55

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

56

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

57

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

58

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

59

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

60

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

61

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

62

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

63

Glassy carbon supercapacitor: 100,000 cycles demonstrated  

Energy Technology Data Exchange (ETDEWEB)

A 5 V glassy carbon capacitor stack was built consisting of four bipolar and two end-plate electrodes. More than 100,000 charging/discharging cycles were applied to test the stability of the double-layer capacitor. Low and high frequency resistances were measured as a function of the number of cycles. (author) 2 figs., 1 ref.

1999-08-01

64

Turbulence in the positive column of a glow discharge  

CERN Document Server

Turbulence in the positive column of a glow discharge

1969-01-01

65

Influence of duration and rate of pulse rise of the applied voltage on ozone concentration in the barrier glow discharge  

International Nuclear Information System (INIS)

The barrier glow discharge between two planar electrodes, covered with dielectric, is studied under high-voltage pulsed power supply. Wide applications of such type of discharges, in particular, for ozone production, stimulated a number of investigations in this direction. In this work we investigated the dependence of ozone concentration on the duration and the rate of pulse rise of the applied voltage. The thyristor converter circuit with the shortening of input pulses on the base of the saturable throttle was used for the realization of this task. The output pulses with amplitude up to 15 kV, repetition frequency of 1 kHz, pulse duration of 0.3 #mu#s (or 7 #mu#s) and the rate of pulse rise of 0.1 #mu#s were generated with this scheme. Measurements of the ozone concentration produced in the air mixture have shown that its value increased by factor two with variation of the rate of pulse rise from 0.5 #mu#s to 0.1 #mu#s ...

2005-09-06

66

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 ...

2011-06-01

67

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 ...

1996-01-01

68

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 ...

69

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 ...

2008-01-01

71

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 ...

2010-01-01

72

Measurements of fluctuations in the flux of runaway electrons to the PLT limiter  

Energy Technology Data Exchange (ETDEWEB)

Fluctuations in the flux of runaway electrons to the limiter have been measured during many PLT discharges. Oscillations at 60, 120, and 720 Hz are driven by variations in the vertical magnetic field which moves the plasma major radius. Fluctuations are seen in the range of 2 ..-->.. 20 kHz due to MHD magnetic islands which extend to the plasma surface. A continuous spectrum of fluctuations is observed up to 200 kHz which correlates with drift-wave turbulence. The magnitude of the driven fluctuations can be used to measure transport properties of the runaway electrons. The amplitude of electron motion due to the MHD and drift-wave oscillations, and hence a measure of the radial size of the instability, can be determined as a function of frequency. The slope of the frequency power spectrum of the drift-wave-induced fluctuations steepens with increasing runaway electron drift orbit displacement during the current drop at ...

1982-07-01

73

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 ...

74

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

75

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

76

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

77

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 ...

1991-10-02

78

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

79

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

80

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

81

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

82

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

83

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 ...

2006-09-15

84

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, ...

2003-12-01

85

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

86

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 ...

2007-07-01

87

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

88

Increased heterozygosity at the Mdh-B locus in fish inhabiting a rapidly fluctuating thermal environment  

Science.gov (United States)

Populations of a common forage fish, red shiner Notropis lutrensis, were sampled from four localities on the Brazos River, Texas, affected by cold-water discharge from a hydroelectric dam and from unaltered sites in the same region. Polymorphism at the Mdh-B locus, encoding supernatant malate dehydrogenase, indicates that populations within 57 km of the dam are distinctive from other regional populations and possess a unique Mdh-B allele, have significantly higher levels of heterozygosity at the Mdh-B locus, represent a homogeneous set that have significantly different Mdh-B zygotic frequencies from other regional populations, and have significantly different Mdh-B zygotic proportions than would be expected under a Hardy-Weinberg equilibrium. Increased levels of heterozygosity in fish within 57 km of the dam were correlated with discharge-associated fluctuations in water temperature at sampling stations.

1981-05-01

89

Frequency Controlled Electric Drives  

International Science & Technology Center (ISTC)

Development of Frequency Controlled Electric Drives

90

Challenges in environmental radiological surveillance around nuclear facilities  

International Nuclear Information System (INIS)

To accomplish the environmental radiological surveillance need of India's ambitious nuclear power programme, Health Physics Division is infusing new technologies and improved analytical techniques for day to day measurements of various radionuclides in different environmental matrices. It is essential to have techniques for measuring the concentration of radionuclides just above the background level since the discharges from the nuclear facilities are very low i.e. in the range of 5-10% of the prescribed discharge limits by the regulatory bodies. In view of developing ultra-sensitive techniques, the aim of ongoing programmes of the division is to meet the challenges of measuring ultra trace level of radioactivity by adopting state of art new instrumentation and improved sample processing techniques. This will allow us to measure the lowest level of radioactivity (3H, 90Sr, 137Cs, 239+240Pu, etc.) in the environment and thereby estimating the ...

2007-06-05

91

Diet and incident venous thromboembolism: The Iowa Women's Health Study  

British Library Electronic Table of Contents (United Kingdom)

Background Little is known about the role of diet in the development of venous thromboembolism (VTE). We explored the prospective relation of dietary patterns, food groups, and nutrients to incident VTE in older women. Methods In 1986, Iowa women aged 55 to 69 years completed a mailed survey, including a 127-item food frequency questionnaire. These data were linked to Medicare data from 1986 to 2004, and International Classification of Diseases discharge codes were used to identify hospitalized VTE cases. Cox regression analyses evaluated relations of 2 principal components?derived dietary patterns, 11 food groups, and 6 nutrients to VTE, adjusted for age, education, smoking status, physical activity, and energy intake. Results Over 19 years of follow-up, 1,950 of the 37,393 women develope...

2009-01-01

92

Dynamic positive column in long-gap barrier discharges  

CERN Document Server

A simple analytical model of the barrier discharge in a long gap between opposing plane electrodes is developed. It is shown that the plasma density becomes uniform over large part of the gap in the course of the discharge development, so that one can speak of a formation of a dynamic positive column. The column completely controls the dynamics of the barrier discharge and determines such characteristics as the discharge current, discharge duration, light output, etc. Using the proposed model, all discharge parameters can be easily evaluated

2005-01-01

93

Electron cyclotron heating  

International Nuclear Information System (INIS)

Electron cyclotron resonance heating (ECH) in BPX is planned as a possible upgrade to supplement the baseline ion cyclotron resonance frequency (ICRF) system. Eventual implementation primarily depends on the development of the required source technology. ECH offers important technical advantages over ICRF: High radio-frequency (FR) power density can be transmitted through ports (P/A >#approx# 100 MW/M"2), and the antenna need not be in contact with the plasma for efficient coupling. In particular, low-field side, linearly polarized (O-mode) power injection will suffice. By controlling the N spectrum, or by steering the antenna, the power deposition profile can be controlled during ramping of the magnetic field even with a fixed frequency source. Because of the possibility of localized power deposition, ECH is a natural candidate for controlling magnetrohydrodynamic (MHD) activity. Sawtooth oscillations may be prevented ...

94

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

96

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

97

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

98

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

99

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 ...

1986-01-01

100

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. ...

2007-08-01

101

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 changes for power ...

1988-05-01

102

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

103

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

104

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 ...

2002-01-01

105

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

106

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

107

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 ...

2002-01-01

108

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

109

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

110

Washboard modes as ELM-related events in JET  

Energy Technology Data Exchange (ETDEWEB)

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

2004-01-01

112

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 likely to be found in ...

2010-01-01

113

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

114

Thermoregulatory responses of rats exposed to 9. 3-GHz radio-frequency radiation  

Energy Technology Data Exchange (ETDEWEB)

Ketamine-anesthetized Sprague-Dawley rats were exposed in H orientation to far-field 9.3-GHz continuous-wave (CW) and pulsed (2 microseconds 500 pps) radiofrequency radiation (RFR) at average power densities of 30 and 60 mW/sq. cm (whole-body average specific absorption rates of 9.3 and 18.6 W/kg, respectively). Irradiation was conducted to cyclicly increase colonic temperature from 38.5 to 39.5 C. Colonic, tympanic, and subcutaneous temperatures, ECG, blood pressure, and respiratory rate were continuously recorded during experimentation. At both power densities, the subcutaneous and tympanic temperature increases significantly exceeded the colonic temperature increase. At both exposure levels, heart rate increased significantly during irradiation and returned to baseline when exposure was discontinued. Blood pressure and respiratory rate did not significantly change during irradiation. There were no significant differences between the effects of CW and pulsed RFR exposure. The levels ...

1987-10-15

115

Reduction of RF-sheaths potentials by compensation or suppression of parallel RF currents on ICRF antennas  

International Nuclear Information System (INIS)

Radio frequency (RF) sheaths are suspected of limiting the performance of present-day ion cyclotron range of frequencies (ICRFs) antennas over long pulses and should be minimized in future fusion devices. Within the simplest models, RF-sheath effects are quantified by the integral VRF = ? E|| ? dl where the parallel RF field E|| is linked with the slow wave. On 'long open field lines' with large toroidal extension on both sides of the antenna it was shown that VRF is excited by parallel RF currents j|| flowing on the antenna structure. In this paper, the validity of this simple sheath theory is tested experimentally on the Tore Supra (TS) ITER-like antenna prototype (ILP), together with antenna simulation and post-processing codes developed to compute VRF. The predicted poloidal localization of high-|VRF| zones is confronted to that inferred from experimental data analysis. Surface temperature distribution on ILP front ...

2010-02-01

116

A High Frequency Platinum Resistance Thermometer System ...  

Science.gov (United States)

... HIGH FREQUENCY, WIRE, ATMOSPHERIC MOTION, SENSITIVITY, PLATINUM, FREQUENCY RESPONSE, AMPLIFIERS, MULTIVIBRATORS. ...

1975-02-01

117

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

118

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 ...

2009-12-16

119

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

120

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

121

Chromosomal damage in human lymphocytes from radio-isotope therapy  

International Nuclear Information System (INIS)

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

122

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

123

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.

124

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

125

Fuel ignition by high voltage capacitive discharges  

Energy Technology Data Exchange (ETDEWEB)

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

1983-03-01

126

Photovoltaic lighting for outdoor telephone booth  

Energy Technology Data Exchange (ETDEWEB)

A free standing outdoor telephone booth is provided with a photovoltaic (PV) array, one or more rechargeable storage batteries and electrical control circuit which includes a temperature compensated control for limiting the supply of electrical energy from the PV array to the rechargeable battery to avoid over charging the battery, an ambient light (solar insolation) sensing circuit for controlling the electrical lamp load, to turn the lamp ON during dark ambient and OFF during light ambient conditions. In addition, the total discharge limit of the storage battery is controlled to a safe operating limit and a means is disclosed to power a fluorescent lamp at energy conserving intensities with energy derived from the rechargeable storage battery. The lamp control circuitry is preferably constituted by a high frequency power inverter with regulated output power to energize a low wattage fluorescent lamp and to dim the fluorescent lamp when the ...

1984-04-03

127

Air breakdown induced by a high-power short-pulse microwave  

Energy Technology Data Exchange (ETDEWEB)

At Himeji Institute of Technology, the high power microwaves with the peak power of 20 MW, frequency of 12 GHz and pulse duration of 14 ns have been produced with a virtual cathode oscillator (vircator). These high power microwaves offer new applications in various fields. One problem in laser-triggered lightning experiment is the strong attenuation of laser energy by rain, cloud and laser-produced plasma. Microwaves propagate in thundercloud with small loss, and also are able to irradiate much extensive region of targets. In this paper, the fundamental experiment on the air breakdown induced by high power, short pulse microwaves is reported. The experimental setup of the vircator diode for microwave generation is shown. The typical evolution of diode voltage, electron beam current and microwave emission from the top in the course of time is shown. The experimental setup for microwave-induced air breakdown and the experimental procedure are explained. The results ...

1996-05-01

128

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

129

Biotoxicity characterization of a produced-water discharge in Wyoming  

International Nuclear Information System (INIS)

The objectives of this paper are to document the physicochemical and aquatic toxicological quality of a beneficial-use produced-water discharge and its effect on a receiving stream in Wyoming. Fish and water-flea survival, growth, and reproduction tests indicated that the discharge and all other sampling stations passed the state effluent biomonitoring acute toxicity testing endpoints. while benthic macroinvertebrates were absent at the discharge point designated by the Natl. Pollutant Discharge Elimination System (NPDES), productive and reproducing populations were present at all other downstream and mixing-zone stations. This investigation confirmed the validity of the beneficial-use subcategory for this oilfield discharge.

130

Electrical Discharge Machining (EDM) Gun Barrel Bore and ...  

Science.gov (United States)

... Accession Number : ADB006226. Title : Electrical Discharge Machining (EDM) Gun Barrel Bore and Rifling Feasibility Study. ...

1974-09-01

131

EPA - Stormwater Discharges from Construction Activities  

Science.gov (United States)

discharges. Proposed Stormwater ELG from Construction Sites - EPA has proposed effluent limitations guidelines (ELGs) and new source performance standards (NSPS) to control...

2011-10-14

132

Field-effect research at the High Voltage Transmission Research Center  

Energy Technology Data Exchange (ETDEWEB)

This report presents information obtained during five different studies of field effects from high voltage transmission lines performed at EPRI's High Voltage Transmission Research Center. The first study is the development of a methodology for the evaluation of the expected frequency of occurrence of specific short-term effects of spark discharges and induced currents caused by overhead high voltage transmission lines. The methodology is divided into the analysis of the expected frequency of occurrence of situations in which induction effects may occur, and the analysis of the expected severity of the effect. The second study is of the electric field in the surface and on the immediate proximity of the strands of stranded conductors used for overhead high voltage lines. In particular, the cases of deformations of stranded conductors, caused by air expansion or by popped out strands, are analyzed for the purpose of ...

1991-02-01

133

Ultra high vacuum test setup for electron gun  

Energy Technology Data Exchange (ETDEWEB)

Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The cathode emission current, work function and ...

2008-05-01

134

Time-varying magnetic fields increase cytosolic free Ca sup 2+ in HL-60 cells  

Energy Technology Data Exchange (ETDEWEB)

Electromagnetic fields have been reported to cause a variety of biological effects. It has been hypothesized that many of these phenomena are mediated by a primary effect on the concentration of cytosolic free calcium ((Ca2+)i). We investigated the effects of exposure to electromagnetic fields on (Ca2+)i in HL-60 cells using the Ca2(+)-sensitive fluorescent indicator indo-1. Indo-1-loaded cell samples were exposed to a radiofrequency electromagnetic field, a static magnetic field, and a time-varying magnetic field, which were generated by a magnetic resonance imaging (MRI) unit. We found that a 23-min exposure to all three fields, in combination, induced a significant increase in (Ca2+)i of 31 +/- 8 (SE) nM (P less than 0.01, n = 13) from a basal level of 121 +/- 8 nM. Also, cells exposed to only the time-varying magnetic field had a mean (Ca2+)i that was 34 +/- 10 nM (P less than 0.01, n = 11) higher than parallel control samples. Separate exposure to the ...

1990-10-01

135

System control and data acquisition of the two new FWCD RF systems at DIII-D  

Energy Technology Data Exchange (ETDEWEB)

The Fast Wave Current Drive (FWCD) system at DIII-D has increased its available radio frequency (RF) power capabilities with the addition of two new high power transmitters along with their associated transmission line systems. A Sun Sparc-10 workstation, functioning as the FWCD operator console, is being used to control transmitter operating parameters and transmission line tuning parameters, along with acquiring data and making data available for integration into the DIII-D data acquisition system. Labview, a graphical user interface application, is used to manage and control the above processes. This paper will discuss the three primary branches of the FWCD computer control system: transmitter control, transmission line tuning control, and FWCD data acquisition. The main control program developed uses VXI, GPIB, CAMAC, Serial, and Ethernet protocols to blend the three branches together into one cohesive system. The control of the ...

1995-10-01

136

Structures and properties of fluorinated amorphous carbon films  

International Nuclear Information System (INIS)

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

2004-07-01

137

Smith-Purcell free-electron laser  

International Nuclear Information System (INIS)

The term Smith-Purcell free electron laser can be employed generally to describe any coherent radiation source in which a diffraction grating is used to couple an electron beam with the electromagnetic field. To date, most practical developments of this concept have focused on devices which operate in the millimeter spectral regime. In this paper construction of a Smith-Purcell free-electron laser operating in the far-infrared (FIR) region using a novel resonator cavity design and the electron beam from a low energy (0.5-5 MeV) radio-frequency accelerator will be discussed. A tunable source in this region would have many applications and since the beam energy is low, the small size and low overall cost of such a device would make it a laboratory instrument. Current projects which are progressing towards developing a FIR source are the programs at Stanford and CREOL. Both of these projects are using permanent magnet undulators to couple the electron beam with the ...

1995-08-21

138

RF plasma nitriding of severely deformed iron-based alloys  

International Nuclear Information System (INIS)

The effect of severe plastic deformation by cold high pressure torsion (HPT) on radio frequency (RF) plasma nitriding of pure iron, as well as St2K50 and X5CrNi1810 steels was investigated. Nitriding was carried out for 3 h in a nitrogen atmosphere at a pressure of 10"-"5 bar and temperatures of 350 and 400 deg. C. Nitrided specimens were analysed by scanning electron microscopy (SEM), X-ray diffraction and micro hardness measurements. It was found that HPT enhances the effect of nitriding leading almost to doubling of the thickness of the nitrided layer for pure iron and the high alloyed steel. The largest increase in hardness was observed when HPT was combined with RF plasma nitriding at 350 deg. C. In the case of pure iron, the X-ray diffraction spectra showed the formation of #epsilon# and #gamma#' nitrides in the compound layer, with a preferential formation of #gamma#' at the expense of the #alpha#-phase at the higher nitriding ...

2003-05-15

139

Measurement of magnetic fields in the Area Metropolitana  

International Nuclear Information System (INIS)

The operation and proper handling of equipment for measuring EMR-300 electromagnetic waves are studied and apply that knowledge to determine which areas of the metropolitan area are mostly affected by exposure to the emission of radiation. This team is able to measure magnetic field strength, electric field strength and power density, also can measure the most important parameters in a simple manner. International standards provide maximum values for these parameters that limit human exposure to such radiation. These standards are based on epidemiological several and laboratory that have been carried out in order to determine in which circumstances a biological entity is exposed to a level of radiation that can cause harm to their health. It focuses on measuring the level of radiation in certain areas of interest, which were chosen because are areas with high population density and also in proximity to antennas that emit electromagnetic waves. Before carrying out the data collection ...

140

High-efficiency Resonant rf Spin Rotator with Broad Phase Space Acceptance for Pulsed Polarized Cold Neutron Beams  

Energy Technology Data Exchange (ETDEWEB)

High precision fundamental neutron physics experiments have been proposed for the intense pulsed spallation neutron beams at JSNS, LANSCE, and SNS to test the standard model and search for new physics. Certain systematic effects in some of these experiments have to be controlled at the few ppb level. The NPD Gamma experiment, a search for the small parity-violating {gamma}-ray asymmetry A{sub Y} in polarized cold neutron capture on parahydrogen, is one example. For the NPD Gamma experiment we developed a radio-frequency resonant spin rotator to reverse the neutron polarization in a 9.5 cm x 9.5 cm pulsed cold neutron beam with high efficiency over a broad cold neutron energy range. The effect of the spin reversal by the rotator on the neutron beam phase space is compared qualitatively to rf neutron spin flippers based on adiabatic fast passage. We discuss the design of the spin rotator and describe two types of transmission-based neutron spin-flip efficiency ...

2008-08-01

141

Flexible organic electronic devices: Materials, process and applications  

Energy Technology Data Exchange (ETDEWEB)

The research for the development of flexible organic electronic devices (FEDs) is rapidly increasing worldwide, since FEDs will change radically several aspects of everyday life. Although there has been considerable progress in the area of flexible inorganic devices (a-Si or solution processed Si), there are numerous advances in the organic (semiconducting, conducting and insulating), inorganic and hybrid (organic-inorganic) materials that exhibit customized properties and stability, and in the synthesis and preparation methods, which are characterized by a significant amount of multidisciplinary efforts. Furthermore, the development and encapsulation of organic electronic devices onto flexible polymeric substrates by large-scale and low-cost roll-to-roll production processes will allow their market implementation in numerous application areas, including displays, lighting, photovoltaics, radio-frequency identification circuitry and chemical sensors, as well as to ...

2008-08-25

142

Copper coatings for minimization of retention and permeation of implanted tritium in aluminum alloy 6061  

Energy Technology Data Exchange (ETDEWEB)

Copper coatings deposited on Al-6061 substrates by radio frequency magnetron sputtering, to prevent the retention and permeation of energetically implanted tritium in Al-6061, were evaluated by a variety of characterization techniques. The coatings, weighing in the 0.03 to 0.088 kg/m{sup 2} range, were smooth and had a fine grain structure. They contained the intermetallic phases Cu{sub 9}Al{sub 4} and CuAl{sub 2} as well as copper. The fractions of Al and Cu in any coating increased and decreased, respectively, with increasing depth below the surface. Furthermore, the fractions of Al and Cu on the coating surface decreased and increased, respectively, with increasing coating weight. There was no texture or preferred orientation in the Cu phase of the coatings. A significant amount of oxygen was also detected at the original substrate surface. Residual stress measurements revealed that, in both Cu and CuAl{sub 2}, the stresses in the coating ...

1999-08-01

143

A simple 5-DoF MR-compatible motion signal measurement system.  

Science.gov (United States)

The purpose of this study was to develop a simple motion measurement system with magnetic resonance (MR) compatibility and safety. The motion measurement system proposed here can measure 5-DoF motion signals without deteriorating the MR images, and it has no effect on the intense and homogeneous main magnetic field, the temporal-gradient magnetic field (which varies rapidly with time), the transceiver radio frequency (RF) coil, and the RF pulse during MR data acquisition. A three-axis accelerometer and a two-axis gyroscope were used to measure 5-DoF motion signals, and Velcro was used to attach a sensor module to a finger or wrist. To minimize the interference between the MR imaging system and the motion measurement system, nonmagnetic materials were used for all electric circuit components in an MR shield room. To remove the effect of RF pulse, an amplifier, modulation circuit, and power supply were located in a shielded case, which was made ...

2011-09-01

144

The Role of Electronegative Impurities in Ozone Generation by High Pressure Discharges  

International Nuclear Information System (INIS)

The high pressure discharges (pulsed or D C corona, barrier, gliding and the others), have been studied both experimentally and theoretically as sources of low temperature plasma for pollution control technologies. The potential of electrical discharge methods has been demonstrated for the decomposition of many types of VOC. The air or oxygen are used as a feed gas in which pollutant is diluted. The ozone production in air or oxygen in such discharges is also discussed

1999-07-11

145

State of macroparticles in the plasma of beam-plasma discharge  

International Nuclear Information System (INIS)

... Union (INTAS), Brussels (Belgium) Science and Technology Center in Unkraine,

2006-09-11

147

Partial discharge in liquid nitrogen  

Science.gov (United States)

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

1976-01-01

149

Modified Helium microwave-induced plasma discharge chamber  

International Nuclear Information System (INIS)

... Mohamed, MM Medical Research Institute (Egypt) Ghatass, ZF Institute of

1999-04-01

151

Dielectric barrier discharge using corona-modified silicone rubber  

Science.gov (United States)

Results from scanning electron microscopy, Fourier transform infrared spectroscopy and the measurement of thermally stimulated current show that a high density of the physical defects and the chemical defects are introduced into the surface of the silicone rubber plates after they are treated by corona discharge plasma. These defects behave electrically as shallow electron traps, leading to the formation of a uniform discharge in air at higher pressure when the corona-modified silicone rubber is used in dielectric barrier discharge.

2008-10-01

157

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

158

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

159

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 ...

2004-02-01

160

Research on Nanosecond Pulse Corona Discharge Attenuation  

Science.gov (United States)

A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control. Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted. The results show that the wave front decreases sharply during the corona discharge along the corona wire. The higher the amplitude of the applied pulse is, the more the amplitude of the wave front decreased. The wave attenuation responds in a lower corona discharge inversely. To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design.

2007-12-01

161

Optogalvanic isotope enrichment of Cu ions in Cu-Ne positive column discharges  

Energy Technology Data Exchange (ETDEWEB)

The isotopic enrichment of copper ions in a positive column Cu-Nu discharge using optogalvanic excitation is analyzed with a rate equation model With excitation at 510.6 nm, the fraction of the ions belonging to the 63-amu isotope of copper is enriched relative to the neutral abundance. Enrichment as large as 10% is calculated when the initial abundance of the neutral isotope is small (< or =0.1) and the discharge current density is large (> or =75 mA/cm/sup 2/). The degree of enrichment is examined as a function of the initial abundance, discharge current, the rate of charge exchange, and the diameter of the discharge tube.

1983-07-01

162

Method for limiting scram discharge water  

International Nuclear Information System (INIS)

Object: To limit the discharge amount of reactor water in a primary system at the time of scram to prevent excessive outflow of reactor water outside the system. Structure: A signal from an upper limit position indicator detects the fact that control rods are completely inserted when the reactor is urgently stopped and the detection signal causes a valve in an outflow line of the discharge water from a control rod driving mechanism to be closed to limit the amount of discharge flown into the scram discharge vessel, thus preventing outflow of reactor water in the primary system after the scram has been initiated. (Kamimura, M.).

163

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

164

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

165

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

166

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

167

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. ...

168

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 ...

169

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

170

Principle of pulse frequency measurement and methods for improving frequency meters accuracy  

Energy Technology Data Exchange (ETDEWEB)

Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed.

1980-01-01

171

Principle of pulse frequency measurement and methods for improving frequency meters accuracy  

International Nuclear Information System (INIS)

Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed. (author).

1980-01-01

173

Average output lasing power of a He-Ne laser as a function of the modulation frequency of resonator losses  

Science.gov (United States)

The frequency dependence of the lasing power of a He-Ne laser was studied using the electrooptic effect in a KDP crystal. The gain profile of the power curve was found to differ noticeably between the high-frequency and low-frequency edges. (AIP). (AIP)

1976-09-01

175

Ultrasound and airflow induced thermal instability suppression of DC corona discharge: an experimental study  

International Nuclear Information System (INIS)

The effect of ultrasound waves, airflow and combined ultrasound with the airflow on the thermal instability suppression of a hollow needle-to-plate electrical discharge was studied experimentally. To evaluate the thermal instability suppression we used the V-A characteristics of the discharge in stationary air, with ultrasound applied in stationary air, and finally when the airflow was supplied into the discharge through the needle without and with ultrasound application. To illustrate the effect of ultrasound, airflow and combined ultrasound with airflow on the discharge thermal instability suppression we also studied the discharge ozone production. We found that in stationary air the application of ultrasound only slightly suppresses thermal instability. A substantial increase of ozone generation was not detected. Application of the airflow through the needle suppressed ...

2006-02-01

176

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

177

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, ...

178

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

179

Ozone generation in a negative corona discharge fed with N_2O and O_2  

International Nuclear Information System (INIS)

Ozone production in a negative corona discharge has been studied experimentally at atmospheric pressure in mixtures of N_2O+O_2 at ambient temperature. Ozone formation was found to be dramatically reduced with increase in the content of N_2O in the mixture. The reaction of O("1D) with nitrous oxide is the most likely process reducing the rate of ozone generation. A considerable decrease in the mean discharge current at a constant voltage was also observed with increasing content of nitrous oxide in the mixture and is attributed to the formation of anions in the discharge. The low values of the calculated mobility of negative charge carriers in the drift region of the discharge is caused by the formation of O"- #centre dot# (N_2O)_n and NO"-#centre dot#(N_2O)_n cluster anions in the drift region of the negative corona discharge.

2004-04-07

180

Fates of dissolved and particulate materials from the Mississippi river immediately after discharge into the northern Gulf of Mexico, USA, during a period of low wind stress  

British Library Electronic Table of Contents (United Kingdom)

In June 2003, we conducted a two-part field exercise to examine biogeochemical characteristics of water in the lower Mississippi river during the 4 days prior to discharge and in the Mississippi river plume over 2 days after discharge. Here we describe the fates of materials immediately after their discharge through Southwest Pass of the Mississippi delta into the northern Gulf of Mexico. Changes in surface water properties immediately after discharge were much larger and more rapid than changes prior to discharge. Total suspended matter (TSM) declined, probably due to sinking, dissolved macronutrients were rapidly diminished by mixing and biological uptake, and phytoplankton populations increased dramatically, and then declined. This decline appeared to begin at salinities of approximatel...

2008-01-01

181

A finite element based model for electrochemical discharge machining in discharge regime  

British Library Electronic Table of Contents (United Kingdom)

Electrochemical discharge machining (ECDM) is a promising hybrid process for high-performance machining of non-conductive glass. ECDM drilling has been found to have different characteristics and material removal mechanisms in discharge regime (less than 300??m in depth) and hydrodynamic regime (more than 300??m in depth); however, these regimes are never separately modeled in existing ECDM models, which leads to large prediction error, especially at low applied voltages and high machining depths. Until now, no model is particularly designed for discharge regime, where most material is removed. In this paper, a finite element based model for ECDM drilling in discharge regime is presented. Material removal subjected to a single spark was simulated using finite element method. The drilling d...

2011-01-01

182

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

183

RF plasma nitriding of severely deformed iron-based alloys  

Energy Technology Data Exchange (ETDEWEB)

The effect of severe plastic deformation by cold high pressure torsion (HPT) on radio frequency (RF) plasma nitriding of pure iron, as well as St2K50 and X5CrNi1810 steels was investigated. Nitriding was carried out for 3 h in a nitrogen atmosphere at a pressure of 10{sup -5} bar and temperatures of 350 and 400 deg. C. Nitrided specimens were analysed by scanning electron microscopy (SEM), X-ray diffraction and micro hardness measurements. It was found that HPT enhances the effect of nitriding leading almost to doubling of the thickness of the nitrided layer for pure iron and the high alloyed steel. The largest increase in hardness was observed when HPT was combined with RF plasma nitriding at 350 deg. C. In the case of pure iron, the X-ray diffraction spectra showed the formation of {epsilon} and {gamma}' nitrides in the compound layer, with a preferential formation of {gamma}' at the expense of the {alpha}-phase at the ...

2003-05-15

184

Operational reactor physics analysis codes (ORPAC)  

International Nuclear Information System (INIS)

Full text: Research reactors have been playing a multi dimensional role in areas of nuclear fuel cycle programme, radio-isotope productions, neutron beam research etc. To ensure an efficient, smooth and safe operation of a nuclear research reactor, many reactor physics evaluations are required on routine basis. As part of reactor core management the important activities are maintaining core reactivity status, core power distribution, xenon estimations, safety evaluation of in-pile irradiation samples and experimental assemblies and assessment of nuclear safety in fuel handling/storage. In-pile irradiation requires a prior estimation of the reactivity load due to the sample, heating rate and the activity developed in it during irradiation. For the safety of the personnel handling irradiated samples the dose rate at the surface of shielded flask housing the irradiated sample should be less than 200 mR/Hr. Therefore, a proper shielding and radioactive cooling of the ...

185

Lower Flathead System Fisheries Study, Executive Summary, Volume I, 1983-1987 Final Report.  

Energy Technology Data Exchange (ETDEWEB)

This Executive Summary, Volume I, of the lower Flathead System Fisheries Study Final Report, was prepared to provide a study overview for persons who are not fisheries scientists. The contents provide an introduction to the study and its objectives, a short description of the study area, a discussion of the major findings and conclusions of the study, and the description of fisheries management alternatives available to managers of the lower Flathead system. Technical reports were prepared for those portions of the study dealing with the lower Flathead River and its tributaries, Volume II, and the South Bay of Flathead Lake, Volume III. The annual hydrographic regime of the Flathead system, consisting of upper rivers, lake and lower river, has been modified by the construction and operation of two major hydroelectric facilities, Hungry Horse Dam on the south fork Flathead River and Kerr Dam at the outlet of Flathead Lake. The modified hydrographic regime has resulted in significant ...

1988-06-01

186

Investigation of the deposit formation in pipelines connecting liquefaction reactors; 1t/d PSU ni okeru ekika hanno tokan fuchakubutsu no seisei yoin ni kansuru ichikosatsu  

Energy Technology Data Exchange (ETDEWEB)

The liquefaction reaction system of an NEDOL process coal liquefaction 1t/d PSU was opened and checked to investigate the cause of the rise of differential pressure between liquefaction reactors of the PSU. The liquefaction test at a coal concentration of 50 wt% using Tanito Harum coal was conducted, and it was found that the differential pressure between reactors was on the increase. By the two-phase flow pressure loss method, deposition thickness of deposit in pipelines was estimated at 4.4mm at the time of end operation, which agreed with a measuring value obtained from a {gamma} ray. The rise of differential pressure was caused by deposit formation in pipelines connecting reactors. The main component of the deposit is calcite (CaCO3 60-70%) and is the same as the usual one. It is also the same type as the deposit on the reactor wall. Ca in coal ash is concerned with this. To withdraw solid matters deposited in the reactor, there are installed pipelines for the withdrawal at the ...

1996-10-28

187

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

International Nuclear Information System (INIS)

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

2007-02-07

188

Formation of the electret state of polymers in a gas discharge plasma  

Science.gov (United States)

The present article studies the electret state of polymers when moving through an alternating-current corona discharge plasma and investigates means for the determination of the transition of the polymeric material from the initial state of the electret when the corona-displaying voltage is increased.

1983-02-01

189

Electrical Discharge Machining (EDM) Gun Barrel Bore and Rifling Feasibility Study.  

Science.gov (United States)

A 12-month program was conducted to advance the technology of the Electrical Discharge Machining (EDM) process to be applicable to the stringent requirements of gun barrel boring and rifling. The type of barrels employed in the test were .220 swift gun ba...

1974-01-01

190

Economic Impact Analysis of Proposed Effluent Limitations Guidelines and Standards for the Pesticide Manufacturing Industry.  

Science.gov (United States)

The report details the economic impact of two alternative regulatory options; a Treated Discharge Option and a Zero Discharge Option on facilities that would have to comply with the regulations as part of the reproposal of effluent limitations and standar...

1992-01-01

191

Cost-Effectiveness Analysis of Proposed Effluent Limitations Guidelines and Standards for the Pesticide Manufacturing Industry.  

Science.gov (United States)

The report analyzes the cost-effectiveness of two alternative regulatory options: A Treated Discharge Option and a Zero Discharge Option. The report compares the total annualized cost incurred for each of the two regulatory options to the corresponding ef...

1992-01-01

192

Analysis of the relation between "3H concentrations in sea water of West Daya Bay and GNP's liquid "3H discharges  

International Nuclear Information System (INIS)

Through the analysis of the relations between "3H monitoring results of sea water in West Daya Bay carried out by Guangdong Environmental Radiation Research and Monitoring Center (GERC) from 1994 to 2000 and the quantity of liquid "3H discharges made by Guangdong Nuclear Power Station (GNPS), the function has been found by fitting to describe the relation between "3H average concentrations (hereafter as to average concentration or concentration) for all sampling points at the same time and the quantity of liquid "3H discharges. "3H instantaneous concentrations or yearly average concentration in West Daya Bay can be estimated conveniently by using this function corresponding to either actual discharges or supposed discharges (the way for hydrodynamic calculation) from the GNPS's yearly "3H liquid discharge. The results have shown that the general influences both actual ...

2001-11-01

193

A device for controlling the degree of discharge intensity of a storage battery  

Energy Technology Data Exchange (ETDEWEB)

The device is designed for automatic testing of the degree of discharge of tractive storage batteries (AB) for electric loaders, electric cars and electric ore locomotives. The basic electrical schematic of the device is cited.

1983-01-01

194

Transverse glow discharges in supersonic air and methane flows  

British Library Electronic Table of Contents (United Kingdom)

Transverse glow discharges in supersonic air and methane flows are studied both experimentally and theoretically. The experiments show that a diffuse volume discharge filling the whole cross section of the flow can easily be initiated in air, whereas a diffuse discharge in a methane flow shows a tendency to transition into a constricted mode. The electron transport coefficients (mobility and drift velocity) and the kinetic coefficients (such as collisional excitation rates of the vibrational levels of a methane molecule, as well as dissociation and ionization rates) are calculated by numerically solving the Boltzmann equation for the electron energy distribution function. The calculated coefficients are used to estimate the parameters of the plasma and the electric field in the positive co...

2006-01-01

197

Pathogenic and nonpathogenic Acanthamoeba spp. in thermally polluted discharges and surface waters  

International Nuclear Information System (INIS)

During spring and autumn, the total number of amoebae and the number of acanthamoeba species able to grow at 37 degrees C were determined in six thermally polluted factory discharges and the surrounding surface waters. The isolated Acanthamoeba strains were studied for growth in axenic medium, cytopathic effect in Vito cell cultures, and virulence in mice. Although more amoebae were isolated in autumn, the number of Acanthamoeba species was lower than in spring, when the percent of pathogenic strains among the isolates was highest. Higher concentrations of amoebae were found in warm discharges, and more virulent strains occurred in thermal discharges than in surface waters.

199

Effect of discharge voltage on an ion sheath formed at a grid in a multi-dipole discharge plasma  

International Nuclear Information System (INIS)

It is experimentally demonstrated that a relatively strong ion-rich sheath formed at a fixed negative bias of the grid can be changed to a rather weak ion sheath (sheath potential weakly retards electrons) only by increasing the discharge voltage in the system. At sufficiently high negative grid bias, an increase of discharge voltage enhances the ion collection current at the grid. An explanation is put forward in support of this experimental observation. A slight density enhancement with a fall in plasma electron temperature is also observed with the increasing negative grid bias. (authors)

2008-03-01

200

CAPACITOR DISCHARGE METAL FORMING  

Science.gov (United States)

... Report Date : JUL 1961. Pagination or Media Count : 39. Abstract : Open-ende Terms: Electrohydraulic forming, Magnetic forming. ...

1961-07-01

201

An overview of standards concerning unwanted electrostatic discharges  

British Library Electronic Table of Contents (United Kingdom)

For users and manufacturers affected by unwanted electrostatic discharges, the publication of standards concerning the control of such discharges is a great improvement and helps to prevent unwanted electrostatic discharges in potentially explosive atmospheres as well as around electrostatically sensitive devices. There are, for instance, handbook-like documents giving recommendations to help set up effective electrostatic suppressing measures and programs. Another group of standards focuses on certain products and processes and is, thus, more specific. A third group deals with test methods and specifications to help manufacturers develop products that are safe. It also helps in comparisons with other products and thus meets the customer's real needs. To assist manufacturers and customers ...

2009-01-01

202

The role of plasma potential in d.c. glow discharge conditions in nitriding process of EJ961 steel  

International Nuclear Information System (INIS)

Results of researches on nitriding process of EJ961 steel are presented in this work. This steel was subjected to nitriding both on the cathode and on the isolated from cathode and anode substrate, that is at so called potential of glow discharged plasma. Nitriding processes were performed using device for glow discharge treatments with cooled anode. (author)

2002-09-18

203

TEM-investigations of erosion craters caused by electrical discharge; TEM-Untersuchungen an Erosionskratern, die durch elektrische Entladungen erzeugt werden  

Energy Technology Data Exchange (ETDEWEB)

Craters were produced in the surface of a Pt-specimen by plasma discharge. Using a Focussed Ion Beam (FIB), TEM-foils of the cross section of the craters were prepared in order to examine the microstructural changes occurring as a result of the discharge impact. The molten material pushed to the edge of the craters was able to be identified. The grains beneath the craters reached the surface of the crater by a mechanism of epitaxial growth. (orig.)

2005-11-01

204

A management scheme for reducing pollution at air discharge facility in advance  

Energy Technology Data Exchange (ETDEWEB)

The developed countries are implementing a policy minimizing damage from environmental pollution by reducing discharge in advance as well as the aftermath of a pollutant. The typical example is to use BAT (Best Available Technology). This is to prevent environmental damage by reducing the discharge of pollutants with available technology and to secure environmental margin to enable industrial activities of future generation. Therefore, the feasibility of introducing BAT requirement system was reviewed by considering foreign examples and Korean situation. 38 refs., 8 figs., 69 tabs.

1998-12-01

205

A kinetic study of ozone and nitric oxides in dielectric barrier discharges for O_2/NO_x mixtures  

International Nuclear Information System (INIS)

A simple model is described to simulate kinetic processes in dielectric barrier discharges for O_2/NO_x mixtures. A threshold of ozone production found experimentally is confirmed by the calculations of this modeling, and the underlying chemical reaction mechanisms are discussed. It is also found that the effects of diffusion processes in the period of the lifetime of O atoms are not important to micro-discharge channels with a large radius, i.e. larger than 150 #mu#m

2002-04-01

206

Negative frequency and complex-carrier modulation and demodulation  

CERN Document Server

Negative frequency has a physical meaning, the complete description of a frequency signal is a rotating complex signal, in complete description, positive frequency signal exp(iwt) and negative frequency signal exp(-iwt) is two distinguishable and independent frequency signals. Because the real-carrier modulation and demodulation do not distinguish positive and negative frequency, so half of the spectrum resources and signal energy are wasted. The complex-carrier modulation uses the distinguishable positive frequency signal exp(iwt) and negative frequency signal exp(-iwt) as the carrier signals, they can carry different information, so the spectrum resources is full used, the complex-carrier demodulation does not lose signal energy, so the spectrum efficiency is improved.

2010-01-01

207

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.

208

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

209

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

210

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

211

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.

212

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

213

The Formation of the Low-sized High Density Plasma Structures in the Self-maintained Plasma-beam Discharge  

International Nuclear Information System (INIS)

The opportunity of use self-maintained plasma-beam discharge in an extended pulsing plasma diode of low pressure for making powerful sources of the soft X-rays is investigated. Conditions of formation of the self-maintained plasma-beam discharge are determined. The mode of making of dense high-temperature plasma on the basis of stannum ions in the discharge is shown. The stannum ions are used as a working element of a radiation sources at pulsing power of electron beam P?10...100 MW. Results of the examination on formation of the dense (np?1016 cm3), small sizes (le?100 eV in conditions of working material evaporation from the anode are given. The total contribution of energy to the discharge has made W < 20 J.

2006-01-01

214

Specific features of the current-voltage characteristics of diffuse glow discharges in Ar:N2 mixtures  

British Library Electronic Table of Contents (United Kingdom)

The characteristics of diffuse glow discharges in pure argon and the Ar + 1%N2 mixture at pressures of 2?80 Torr were studied experimentally and numerically. The discharge operated in a molybdenumglass tube with an inner diameter of 2.8 cm and interelectrode distance of 75 cm. The current-voltage characteristic of the discharge and the populations of the N2(B3? g ) and N2(C3? u ) states were measured. It is shown that, at relatively low pressures (P 15 Torr), the current-voltage characteristic of a discharge in the mixture lies lower than that in pure argon. As the pressure increases, the effect of the reduction in the discha...

2010-01-01

215

Numerical simulation of a pulsed corona discharge plasma  

Science.gov (United States)

In this paper we study theoretically a pulsed corona discharge plasma in air at atmospheric pressure. A self consistent one-dimensional model, using a flux-corrected transport numerical scheme, is presented to achieve it. The charged particle kinetics in this model are described by one-dimensional continuity equations coupled with Poisson's equations. The spatio-temporal local field, charge density variations and the velocity profile of an ionizing front are calculated to describe the dynamical behavior of corona discharge plasmas. The simulation results of a wire-in-cylinder corona discharge plasma explain the physical mechanisms of discharge processes. These results may also be apply to obtain the optimizing parameters for designing the plasma reactor.

2001-10-01

216

Liquid radioactive waste discharges from B plant to cribs  

Energy Technology Data Exchange (ETDEWEB)

This engineering report compiles information on types and quantities of liquid waste discharged from B-Plant directly to cribs, ditches, reverse wells, etc., that are associated with B-Plant. Waste discharges to these cribs via overflow form 241-B, 241-BX, and 241-BY tank farms, and waste discharged to these cribs from sources other than B-Plant are discussed.Discharges from B-Plant to other cribs, unplanned releases, or waste remaining in tanks are not included in the report. Waste stream composition information is used to predict quantities of individual chemicals sent to cribs. This provides an accurate mass balance of waste streams from B-Plant to these cribs. These predictions are compared with known crib inventories as a verification of the process.

1996-05-29

217

Erosive radially-slotted discharge in sheet current mode  

CERN Document Server

New non-stationary non-contracted form of the erosive radially-slotted discharge as a thin round sheet with the current of the azimuth direction have been discovered, its existence beings stipulated by a radial transport-wave fluxes. Characteristic features of this discharge is self-confinement of the discharge current magnitude, corresponding decrease of the current pulse duration and occurrence of an energy and substance ejection with rather unusual properties. Measurements of kinetics of the discharge current, the plasma radiation intensity and an electrical probe signal, as well as the transmission electron microscope investigations of characteristic aerodisperse aggregates arising the erosive phase, have been carried out. The probe signal duration was about 10 times greater than that of the current; its kinetics was complicated suggesting existence in the slot of two components with fundamentally ...

2001-01-01

218

Electrostatic discharge effects on EBW detonators  

Science.gov (United States)

With appropriate circuit resistance and inductance and sufficient stored energy, discharging a charged human body or component through an exploding bridgewire (EBW) detonator may cause the detonator to function or may damage the detonator. We have studied the effects of electrostatic discharge (ESD) on a number of exploding bridgewire detonators which were subjected to discharges which passed directly through the bridgewires (pin-to-pin), as well as discharges which passed from the bridge to the metal case of the detonator (pin-to-case). We have performed calculations to determine the values of inductance and resistance for which burst and melt may occur for given ESD sources, using a phenomenological model of bridgewire burst in a computer code called FIRESET. Bridge melt was computed using the same computer code, but using experimental values of bridge resistivity and specific heat up to melt. 13 ...

1991-04-01

219

Effects of Nitrogen Gas Ratio on Nitride Layer and Microhardness of Tool Steel(SKH51) in Plasma Nitriding  

Energy Technology Data Exchange (ETDEWEB)

Pulsed DC-plasma nitriding has been applied to form nitride layer having only a diffusion layer. The discharge current with the variation of discharge gases is proportional to the intensity of N{sub 2}{sup +} peak in optical emission spectroscopy during the plasma nitriding. The discharge current, microhardness in surface of substrate and depth of nitride layer increased with the ratio of N{sub 2} to H{sub 2} gas in discharge gases. When the ratio of N{sub 2} to H{sub 2} is lower than 60% in the discharge gases, high microhardness value of 1100Hv nitride layer which contains no compound layer has been formed. (author). 20 refs., 6 figs., 1 tab.

2002-06-01

220

Capacity-coupled multidischarge for atmospheric plasma production  

International Nuclear Information System (INIS)

We propose a method of plasma production by capacity-coupled multidischarge (CCMD) at atmospheric pressure. The discharge gaps in the CCMD consist of a common electrode and a number of compact electrodes (CCE) which are directly coupled with small capacitors for quenching the discharge. A simple CCE structure is provided by a cylindrical capacitor, the inner conductor of which is used as a gap electrode. A short pulse discharge is observed to appear homogeneously at each CCE. A charge transfer for the single-pulsed discharge is 10-100 times as large as that of the conventional dielectric barrier discharge. A high efficiency of ozone production has been confirmed in the CCMD using O_2 gas. A device configuration of the CCMD is quite flexible with respect to its geometrical shape and size. The CCMD could be used to produce plasmas for various kinds of industrial applications at ...

2003-12-29

221

The two power limits conditioning step frequency in human running.  

UK PubMed Central (United Kingdom)

1. At high running speeds, the step frequency becomes lower than the apparent natural frequency of the body's bouncing system. This is due to a relative increase of the vertical component of the muscular...Full Text Available

1991-06-01

222

Far-field model of the regional influence of effluent plumes from ocean thermal energy conversion (OTEC) plants  

Science.gov (United States)

Ocean thermal energy conversion (OTEC) plants discharge large volumes of cold water into the upper ocean. A three-dimensional, limited-area model was developed to investigate the regional influence of the far-field effluent plume created by the negatively buoyant discharge. The model was applied to discharges from a 40-MW/sub e/ OTEC plant into coastal waters characterized by various ambient ocean conditions. A typical ambient temperature structure and nutrient distribution, as well as the behavior of the effluent plume itself, were strongly modified by the discharge-induced circulation. Although temperature perturbations in the plume were small, upward entrainment of nutrients from below the thermocline was significant. The regional influence of discharges from an 80-MW/sub e/ OTEC plant, the interactions between the discharges from two adjacent 40-MW/sub e/ ...

1985-07-01

223

Electrical breakdown at low pressure in the presence of a weak magnetic field  

Energy Technology Data Exchange (ETDEWEB)

Electron trapping in crossed electric and magnetic fields is an important mechanism by which electrical discharges can develop in low pressure gases. The authors report observations of discharges produced by this mechanism around a spherical anode in two space simulation chambers, namely the Space Plasma Interaction Experiment (SPIE) at the University of Maryland, and the NASA-Lewis B-2 chamber. They have identified two types of discharges in these experiments. In the B-2 chamber, the breakdown takes the form of a runaway dischage with spherical topology, limited only by the ability of the power supply to provide the current. In the SPIE chamber this type of discharge also occurs, in addition to a low current toroidal discharge which is observed at higher magnetic fields. They present measurements of both types of discharge and show how the trapping effect of ...

1990-05-01

224

Pitch discrimination by ferrets for simple and complex sounds  

UK PubMed Central (United Kingdom)

Although many studies have examined the performance of animals in detecting a frequency change in a sequence of tones, few have measured animals' discrimination of the fundamental frequency...Full Text Available

2009-09-01

225

Numerical Simulation of Quarry Source and Reflection ...  

Science.gov (United States)

... that range from relatively low frequency strong ground motion modeling [Vidale et al., 1985] to high frequency reverse time migration of seismic ...

1990-08-01

226

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

227

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

228

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 ...

229

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

230

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

231

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

232

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

233

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

234

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.).

235

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

236

Heteroepitaxial growth of In-face InN on GaN (0001) by plasma-assisted molecular-beam epitaxy  

International Nuclear Information System (INIS)

The thermodynamic aspects of indium-face InN growth by radio frequency plasma-assisted molecular-beam epitaxy (rf-MBE) and the nucleation of InN on gallium-face GaN (0001) surface were investigated. The rates of InN decomposition and indium desorption from the surface were measured in situ using reflected high-energy electron diffraction and the rf-MBE 'growth window' of In-face InN (0001) was identified. It is shown that sustainable growth can be achieved only when the arrival rate of active nitrogen species on the surface is higher than the arrival rate of indium atoms. The maximum substrate temperature permitting InN growth as a function of the active nitrogen flux was determined. The growth mode of InN on Ga-face GaN (0001) surface was investigated by reflected high-energy electron diffraction and atomic force microscopy. It was found to be of the Volmer-Weber-type for substrate temperatures less than 350 deg. C and of the ...

2005-06-01

237

Fermilab Steering Group Report  

Energy Technology Data Exchange (ETDEWEB)

The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOVA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building ...

2007-01-01

240

Precise calculation of transition frequencies of hydrogen and deuterium based on a least-squares analysis  

CERN Document Server

We combine a limited number of accurately measured transition frequencies in hydrogen and deuterium, recent quantum electrodynamics (QED) calculations, and, as an essential additional ingredient, a generalized least-squares analysis, to obtain precise and optimal predictions for hydrogen and deuterium transition frequencies. Some of the predicted transition frequencies have relative uncertainties more than an order of magnitude smaller than that of the g-factor of the electron, which was previously the most accurate prediction of QED.

2005-01-01

242

Nonlinear air-coupled emission: The signature to reveal and image microdamage in solid materials  

International Nuclear Information System (INIS)

It is shown that low-frequency elastic vibrations of near-surface planar defects cause high-frequency ultrasonic radiation in surrounding air. The frequency conversion mechanism is concerned with contact nonlinearity of the defect vibrations and provides efficient generation of air-coupled higher-order ultraharmonics, ultrasubharmonics, and combination frequencies. The nonlinear air-coupled ultrasonic emission is applied for location and high-resolution imaging of damage-induced defects in a variety of solid materials.

2007-12-17

249

Vacuum ultraviolet radiometry of xenon positive column discharges  

Energy Technology Data Exchange (ETDEWEB)

In order to judge the potential fluorescent lamp applications of various low-pressure positive column discharges it is necessary to measure the absolute power emitted in the ultraviolet region of the spectrum. For rare-gas discharges the principle emission occurs in the vacuum ultraviolet so that it is difficult to measure the radiant emittance (power per unit area) of the resonance radiation by standard methods. Two independent techniques are discussed for measuring the radiant emittance of positive column discharges in the vacuum ultraviolet. These techniques are used to study xenon positive column discharges at the resonance wavelength of 147 nm. The first method relies on the measurement of the resonance level density by absorption techniques. The effective decay rate of the resonance level is then determined by the simulation of resonance radiation transport. These two quantities are combined to ...

1995-10-01

250

VUV efficiency and radiant emittance characterization of xenon positive column discharges  

Energy Technology Data Exchange (ETDEWEB)

The pure xenon dc positive column discharge has been characterized for various xenon pressures, currents, and discharge tube radii. The absolute output at the 147 nm resonance transition has been measured using two independent techniques to yield the radiant emittance at 147 nm (power per unit surface area). The efficiency of 147 nm production is obtained by combining the measured radiant emittance with the measured electrical power per unit length deposited in the gas. The radiant emittance and the efficiency are the two principle figures of merit for characterizing the discharge as a source of VUV radiation. It is observed that the trends in efficiency and radiant emittance change substantially when the discharge transitions from two-step electron impact excitation/ionization at higher pressures to single-step electron impact ionization at lower pressures. Modeling of the xenon positive column ...

1996-12-31

251

Recurrent plot analysis of discharge sequences in tracking test of polybutylene polymers  

Energy Technology Data Exchange (ETDEWEB)

Polymers are required to use in radiation environments as insulation materials. However, they often suffer from tracking failure. There is an increasing demand to evaluate radiation effects on dielectric performance. This paper presents a recurrence plot (RP) approach to analyse surface discharge sequences of gamma-ray irradiated polymer materials based on tracking test. Studying the non-linear characteristics of discharge sequences can assist in understanding the underlying mechanism of the discharge process. Discharge sequences of the test are extended to m-dimensional phase space by using the phase space reconstructed method. As test samples, polybutylene terephthalate (PBT) and polybutylene naphthalate (PBN) were irradiated to 100 kGy and then up to 1 MGy with a dosage rate of 10 kGy h{sup -1} by using a {sup 60}Co gamma source. The tracking tests were carried out according to the test method ...

2008-10-07

252

Mercury-free fluorescent lighting  

Energy Technology Data Exchange (ETDEWEB)

A brief comparative review of possible mercury free fluorescent lighting technologies is presented, including rare-gas positive column discharges, molecular discharges, and dielectric barrier discharges. Detailed experimental results on xenon positive column discharges will then be considered. In order to judge whether xenon-based discharges are a viable UV source it is necessary to measure the radiant emittance (power per unit area) for the vacuum ultraviolet (VUV) resonance xenon emission at 147 nm. Two techniques to determine the VUV radiant emittance have been developed and applied to xenon discharges. One method combines the measured resonance level density using absorption spectroscopy and a calculation of the trapped decay rate for the resonance radiation to arrive at the radiant emittance at 147 nm. A second method utilizes a direct measurement of the ...

1996-05-01

253

Generation of ozone by pulsed corona discharge over water surface in hybrid gas-liquid electrical discharge reactor  

International Nuclear Information System (INIS)

Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min"-"1), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns duration in Ar/O_2 ...

2005-02-07

254

Zn/gelled 6M KOH/O{sub 2} zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

2006-09-13

255

Oxidation of Propylene with Oxygen and Air in a Barrier Discharge in the Presence of Octane  

British Library Electronic Table of Contents (United Kingdom)

Oxidation of propylene with oxygen, air and a mixture of nitrogen?oxygen in a barrier discharge is investigated. The selectivity towards formation of propylene oxide in pure oxygen is shown to be as high as 45 wt% and the propylene conversion ratio is found to be 12.9 wt%. In the oxidation with air, the propylene oxide selectivity is 23 wt%, while the conversion is 7.5 wt%. The values of propylene conversion and selectivity towards formation of propylene oxide in a barrier discharge are consistent with those obtained by the thermocatalytic methods for production of propylene oxide.

2011-01-01

256

Ignition system  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an ignition system of an internal combustion engine which consists of: a permanent magnet supported by a rotary member of the engine adapted to rotate in synchronism with a rotary shaft of the engine; a generating coil for generating an electromotive force to produce an electric current as the permanent magnet acts on the generating coil during the rotation of the rotary member; an ignition capacitor charged by the electric current generated by the generating coil; a thyristor caused to turn on by a counter electromotive force generated by the generating coil to thereby cause the ignition capacitor to begin to discharge; and an ignition coil generating a high voltage as the ignition capacitor begins to discharge, to cause a spark discharge to take place in an ignition plug of the internal combustion engine.

1986-09-16

257

Glow Discharge Plasma Nitriding of AISI 304 Stainless Steel  

International Nuclear Information System (INIS)

Glow discharge plasma nitriding of AISI 304 austenitic stainless steel has been carried out for different processing time under optimum discharge conditions established by spectroscopic analysis. The treated samples were analysed by X-ray diffraction (XRD) to explore the changes induced in the crystallographic structure. The XRD pattern confirmed the formation of an expanded austenite phase (#gamma#_N) owing to incorporation of nitrogen as an interstitial solid solution in the iron lattice. A Vickers microhardness tester was used to evaluate the surface hardness as a function of indentation depth (#mu#m). The results showed clear evidence of surface changes with substantial increase in surface hardness.

2007-08-01

258

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

International Nuclear Information System (INIS)

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

2008-03-01

259

Spontaneous and stimulated Raman studies of vibrational dephasing in condensed phases  

Energy Technology Data Exchange (ETDEWEB)

Vibrational dephasing in condensed phases is studied from both a theoretical and experimental standpoint. A theory is presented which describes the dynamics of motional or exchange processes in weakly perturbed systems. This general formalism, which has been previously used to describe motional narrowing in magnetic resonance, is applied to vibrational spectroscopy. The model treats the case of a high frequency vibration anharmonically coupled to a low-frequency vibration. Intermolecular exchange of low frequency vibrational quanta results in a temperature dependent broadening and frequency shift of the high frequency vibration. Analysis of experimental data by this model yields both the exchange rates and the anharmonic couplings.

1980-05-01

260

Frequency response characteristics of the fuzzy polar power system stabilizer  

Energy Technology Data Exchange (ETDEWEB)

The fuzzy polar power system stabilizer (FPPSS) which has been recently developed is analyzed using frequency domain methods. the frequency domain approach allows the PSS designer to compare the new FPPSS with more conventional controllers. The significance of the three FPPSS design parameters are readily seen from the frequency response data, and their relationship to the conventional lead-lag design approach can be evaluated. Furthermore, the frequency response data for the FPPSS allows an alternate design approach for this stabilizer, and can be used to develop information concerning the small signal stability of the resulting system.

1995-06-01

261

Vacuum arc ignition by penning discharge in a strong magnetic field  

Energy Technology Data Exchange (ETDEWEB)

Vacuum arc with cathode spots on the cold electrode is widely used as a plasma generator in a such kind of devices like metal ion sources, plasma cathode electron guns, thing films deposition facilities and others. Most vacuum arc devices utilize a high voltage discharge across an insulator surface to provide a trigger plasma which in turn initiates the main arc discharge. Operation of vacuum arc in a repetitively pulsed mode required a stable triggering system for the long time. But with a discharge across the insulators the number of stable pulses is limited by 100,000 or little bit more. The better method for vacuum arc ignition is low pressure discharge. As shown in this paper it is possible to increase the lifetime of the ignition system in 10 times at least, but negative characteristic of this system is a relatively high pressure (about 0.1 mtorr). In some kinds of vacuum arc applications it is ...

1995-12-31

263
264

TOXCHEM: Predicting the fate of toxics in wastewater treatment plants  

Energy Technology Data Exchange (ETDEWEB)

TOXCHEM is a microcomputer based modelling system for predicting the fate of toxic contaminants in wastewater treatment plants. The package evaluates concentrations of toxics in final effluent and waste sludge, and mass air emissions from municipal or industrial activated sludge wastewater treatment plants. Maximum allowable influent concentrations of toxics required to meet effluent discharge or air emission limits can also be estimated. The package contains a read-only database with treatability parameters for over 100 contaminants, including organic compounds and metals. If effluent or sludge quality limits have been specified, treatment plant owners and operators can use the package to estimate the permissable discharge limits for dischargers to their collection system. A hypothetical example is provided of application of the software to a planning problem involving the start up of a new operation that would ...

1991-12-01

265

Syndromic management of urethral discharge in Ghanaian pharmacies  

UK PubMed Central (United Kingdom)

Objectives: To evaluate the training of pharmacists in Accra, Ghana, in the syndromic management of STIs. Methods: We randomly selected 50 pharmacy outlets that had...Full Text Available

2000-12-01

266

SAFETY--Water Resources Division National Pollutant Discharge...  

Science.gov (United States)

Provisions (a) NPDES field personnel shall be currently trained and certified in CPR and basic first-aid procedures. (b) NPDES field personnel shall be aware of the...

2011-09-24

267

REVIEW OF EXPLOSIVE (CHEMICAL) FORMING  

Science.gov (United States)

... explosive (shotgun shells, etc.) method of forming is being replaced--for the most part--by the electri- cal discharge and magnetic forming methods. ...

1965-04-01

268

Plasma oxidation for achieving supported TiO2 photocatalysts derived from adsorbed TiCl4 using dielectric barrier discharge  

International Nuclear Information System (INIS)

At atmospheric pressure and room temperature, dielectric barrier discharge induced plasma oxidation for achieving supported TiO2 photocatalysts derived from TiCl4 adsorbed onto ?-Al2O3 pellets was studied. The supported TiO2/?-Al2O3photocatalysts prepared by a cyclic 'adsorption-discharge' approach, without requirement of heat treatment, exhibit high activity in the photocatalytic degradation reaction of formaldehyde. The mass spectra and optical emission spectra during O2/Ar discharge for oxidizing the adsorbed-state TiCl4 were measured. The mechanism for the TiO2 formation from adsorbed-state TiCl4 by plasma oxidation was discussed.

2007-03-21

269

Ozone production process in pulsed positive dielectric barrier discharge  

International Nuclear Information System (INIS)

The ozone production process in a pulsed positive dielectric barrier discharge (DBD) is studied by measuring the spatial distribution of ozone density using a two-dimensional laser absorption method. DBD occurs in a 6 mm point-to-plane gap with a 1 mm-thick glass plate placed on the plane electrode. First, the propagation of DBD is observed using a short-gated ICCD camera. It is shown that DBD develops in three phases: primary streamer, secondary streamer and surface discharge phases. Next, the spatial distribution of ozone density is measured. It is shown that ozone is mostly produced in the secondary streamer and surface discharge, while only a small amount of ozone is produced in the primary streamer. The rate coefficient of the ozone production reaction, O + O_2 + M #-># O_3 + M, is estimated to be 2.5 x 10"-"3"4 cm"6 s"-"1.

2007-01-07

270

National Advisory Committee for Aeronautics 1952 - NASA Technical ...  

Science.gov (United States)

By Charles E. Watkins. 2458. An Instrument Employing a Coronal Discharge for ..... Grover, W. S. Hyler, and L. R. Jackson. 2640. Interaction of Column and ...

271

Military Handbook: Electrostatic Discharge Control Handbook ...  

Science.gov (United States)

... (Metric) 80 Page 24. MIL-HDBK-263B MIL-STD-2073-1 - DOD Materiel Procedures for Development and Application of Packaging Requirements. ...

1994-07-31

272

Microwave excitation of a CO/sub 2/ laser. Master's thesis  

Energy Technology Data Exchange (ETDEWEB)

A flowing carbon dioxide laser was operated at low pressures up to 4 torr. Excitation of the laser was provided using various combinations of direct current (DC), pulsed microwave, and continuous wave (CW) microwave excitation. The microwaves were in the 2.45 GHz band and were coupled into the gas using a slow-wave interdigital transmission line. Laser output of 25 milliwatts (mw) was achieved using a DC discharge only. A combination of a DC discharge and pulsed microwaves doubled the output and resulted in some modulation. Changing the laser gas mixture and pulsed microwave field characteristics allowed some flexibility in the modulation. Lasing was not achieved with excitation from the CW microwaves alone due to the formation of localized discharges. Using pulsed microwaves to sustain the discharge and CW microwaves to pump the laser, a quasi-CW output of 55 mw was achieved.

1983-12-01

273

Effect of the tide on the diffusion of "3H in the liquid effluent discharged from Daya Bay Nuclear Power Station  

International Nuclear Information System (INIS)

The tide field at the time of liquid effluent discharging from Daya Bay nuclear power station, and the average water speed at the monitoring points in west Daya Bay from the time of discharging to the time of sampling were calculated by ADI (Alternating Direction Implicit) method. By comparing analysis, the difference of "3H diffusion between spring tide and neap tide (the expansion of "3H within one day of spring tide is greater than that within one day of neap tide) was found. So, an equivalent diffusion time is introduced to modify the original model, and a better attenuation relation between the average "3He concentration in west Daya Bay and the time since the liquid "3H discharging is obtained. (authors)

2006-07-01

274

Do Dreissenid Mussels Affect Lake Erie Ecosystem Stability Processes?  

Science.gov (United States)

... associated with non-reporting of phosphorus input from combined sewer overflow discharge all could potentially play a part in ... ...

275

Investigation of the frequency-dependence of the MTC noise estimator  

International Nuclear Information System (INIS)

The Moderator Temperature Coefficient of reactivity (MTC) was earlier proven to be properly determined via noise analysis when the neutron noise is measured locally and when the radial average of the moderator temperature noise is used. Nevertheless, measurements revealed that the MTC was correctly estimated on a much narrower frequency band (0.6 - 0.7 Hz) than expected (0.1 - 1.0 Hz). The present paper investigates the effect of the feedback on the MTC determination using this new MTC noise estimator (which could explain the deviation at low frequencies, i.e. between 0.1 - 0.5 Hz) and the effect of the detector time constants (which could explain the deviation at high frequencies, i.e. between 0.7 - 1.0 Hz). For that purpose, a coupled neutronic/thermalhydraulic model of the Ringhals-3 PWR is developed in the frequency-domain, based on a radial 2-dimensional heterogeneous representation of the core. ...

2005-09-12

276

Thermal transport during electron cyclotron heating in the TEXT tokamak  

International Nuclear Information System (INIS)

Electron Cyclotron Heating experiments have been performed on the TEXT tokamak using Varian gyrotron. Some degradation of electron energy confinement is observed for sawtoothing and non-sawtoothing discharges. Sharp electron temperature profiles are produced in high-q discharges by extremely localized ECH power deposition.

1989-05-01

277

The possible impact of atmospheric radioactive discharges from UK nuclear installations on acid deposition  

International Nuclear Information System (INIS)

The effect of atmospheric radioactive emissions from United Kingdom nuclear installations on acid deposition is assessed. Nitrogen oxide and ozone production resulting from and associated with discharges of airborne radioactivity, comparison with conventional emissions, and the direct effects of radioactive emissions on trees, are all discussed. (UK).

278

The low-current low-temperature plasma generators  

Energy Technology Data Exchange (ETDEWEB)

In this article, the results of low-current gas-discharge plasma generator investigations carried out by a group of scientists from the Kazan' Aviation Institute are presented. When considered necessary, the results are compared with the data obtained by other authors. The basic configurations and theoretical calculation peculiarities of plasma generators are described. The electrical, thermal and energy characteristics of discharges in gas flows, as well as summarised empirical formulae and experimental data necessary for calculations and design of plasma devices are presented. (author)

2000-07-01

279

Superconducting magnetic system with the controllable inductance of a winding  

International Nuclear Information System (INIS)

The experimental superconducting magnetic system of 0.5 MJ energy storage is described. The step variation of the winding inductance provides a control by the discharge current at the energy output on a high-ohmic load. The voltage on a load is 45 kV at the current 1100 A under the controllable discharge conditions. The energy transfer coefficient constitutes 0,76 under the maximum-to-minimal current ratio equal to 1.3. 7 refs., 3 figs., 2 tabs.

280

Problems and solutions of the IFSMTF power and switch system  

Energy Technology Data Exchange (ETDEWEB)

Solutions have been found for the problems encountered with the coil power and switching systems of the International Fusion Superconducting Magnet Test Facility (IFSMTF). The coil power system provides the filtered dc sources (+- 12 V dc; 25,000 A) for charging and discharging the coils of the IFSMTF experiment. The switching system provides the means of transferring the coil current into a dump resistor when a rapid discharge of a coil is required due to a coil failure (quench) or other system abnormalities.

1985-01-01

281

Modeling Transient Discharge into a Tunnel Drilled in a Heterogeneous Formation  

British Library Electronic Table of Contents (United Kingdom)

Abstract An analytical model is developed to predict transient discharge flow into a tunnel drilled at various speeds through a heterogeneous formation. This model relies on simplifying assumptions commonly enforced in hydrogeologic engineering, and combines the convolution and superposition principles to account for composite sections with arbitrary parametric contrasts. An application to the data monitored during the exploratory drilling of an Alpine tunnel confirms the validity of the approach.

2007-01-01

282

Breakdown and discharges in dense gases governed by runaway electrons  

Energy Technology Data Exchange (ETDEWEB)

The phenomenon of runaway electrons (REs) at high values of the ratio field intensity/gas number density {ital E}/{ital N} and {ital N} up to the Loshmidt number {ital N}{sub {ital L}}{approx_equal}2.7{times}10{sup 19} cm{sup {minus}3} is described. REs are shown to govern the breakdown and discharges at such condition. {copyright} {ital 1996 American Institute of Physics.}

1996-03-01

283

An Explanation for Positive Differential dc Voltage-Current Characteristics in Weakly Ionized, Low-Pressure Positive Column Gas Discharge Plasmas  

Energy Technology Data Exchange (ETDEWEB)

A physical explanation is given for the positive differential voltage-current characteristic seen at low current in weakly ionized, low-pressure positive column discharges in argon/mercury gas mixtures. {copyright} {ital 1996 The American Physical Society.}

1996-07-01

284

Nonlinear response and stability of a spindle system supported by Ball bearings  

Energy Technology Data Exchange (ETDEWEB)

In this effort, the nonlinear responses and stability of a spindle system supported by ball bearings are presented. The dynamics of this system is described by a set of second order differential equations with a nonlinear piecewise smooth force. The Floquet theory is applied to investigate the stability of the periodic solution. Due to the loss of contact between the raceways and balls in the ball bearing, the bending of the frequency response curves switch to the left at the weak resonance region, which is similar to the frequency response curves of a system with a soft spring. With the decrease of the bearing clearance, the bending of the frequency response curves switch to the right, which is similar to the frequency response curves of a system with a hard spring. Increase of the frequency ratio, the bending of frequency response curves transforms from left ...

2010-09-15

285

High-precision Absolute Distance and Vibration Measurement using Frequency Scanned Interferometry  

CERN Document Server

In this paper, we report high-precision absolute distance and vibration measurements performed simultaneously with frequency scanned interferometry using a pair of single mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse Fabry-Perot interferometer(F-P) was used to determine frequency changes during scanning. Two multi-distance-measurement analysis techniques were developed to improve distance precision and to extract the amplitude and frequency of vibrations. Under laboratory conditions, a precision of 40 nm was demonstrated for an absolute distance of approximately 0.45 meters using the first analysis technique. The second analysis technique has capability to measure vibration frequencies ranging from 0.1 Hz to 100 Hz with minimal amplitude on few nanometers order without a priori ...

2004-01-01

286

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

287

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

288

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

289

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

290

Electrochemical properties of Cu{sub 2}O/Cu composite particles prepared by a novel and facile method  

Energy Technology Data Exchange (ETDEWEB)

In this study, Cu{sub 2}O/Cu composite particles were synthesized using an innovative chemical reduction method without any template and surfactant. X-ray diffraction (XRD) analysis revealed that the product mainly consisted of Cu{sub 2}O phase coexisting with a Cu phase. FE-SEM images showed that the octahedral shaped particles were Cu{sub 2}O. The electrochemical performance of the Cu{sub 2}O/Cu particles was investigated with regards to the working electrode material in alkaline solution. The particles had a maximum discharge capacity of 222.9 mAh/g at a discharge current density of 60 mA/g and a high value of 109.1 mAh/g after 50 charge-discharge cycles. Cyclic voltammetry revealed that the reaction between Cu{sub 2}O and Cu is the major electrochemical reaction during the charging and discharging process. Electrochemical impedance spectroscopy revealed that the formation of Cu{sub 2}O on the ...

2010-07-01

291

Trends and Controls on Summer Surface-Water Temperatures in Salmonid-Bearing Headwater Streams in Two Common Geomorphic Settings, Kenai Peninsula, Alaska  

Science.gov (United States)

Stream temperature is an important physical characteristic of headwater streams that plays a critical role in the presence and health of juvenile salmonids. Headwater stream temperature was documented in two geomorphic settings on the Kenai Peninsula, Alaska, focusing on the variation in temperature induced by diffuse groundwater discharge and variable air temperature. Eighteen headwater stream reaches were studied in four watersheds, with 11 drainageway sites and seven discharge-slope sites. In drainageway sites, low-gradient streams flow through broad valleys with groundwater-fed fen wetlands; in discharge-slope sites, high-gradient streams flow through narrow valleys with groundwater-fed slope wetlands. At all 18 sites, hourly stream temperatures were measured for one year. At one drainageway and one discharge-slope site, groundwater temperatures, stream stages, and groundwater heads in the local ...

2010-12-01

292

Non-thermal atmospheric pressure discharges for surface modification  

International Nuclear Information System (INIS)

Throughout the last decades, plasma technology has been established in a series of surface treatment applications, e.g. for semiconductor processing or optical coatings. The majority of plasma assisted technologies is based on low pressure processes. In recent years, however, non-thermal atmospheric pressure discharges have attracted considerable interest because of their simplified technical devices for industrial applications as compared to low pressure processes which require vacuum equipment. Hence, batch processing can be avoided, thus facilitating the implementation of plasma process steps into production lines. Investment costs are cut down significantly. The use of atmospheric pressure plasmas for technical applications dates back to the ozone production with dielectric barrier discharges (DBD) by Siemens in 1857. Lately, the application of atmospheric pressure plasmas for surface treatment has been reported, e.g. for the treatment of ...

293

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

294

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).

295

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

296

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

297

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

298

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

299

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

300

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

301

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

302

Scaling of swim speed and stroke frequency in geometrically similar penguins: they swim optimally to minimize cost of transport  

UK PubMed Central (United Kingdom)

It has been predicted that geometrically similar animals would swim at the same speed with stroke frequency scaling with mass−1/3. In the present study, morphological and behavioural...Full Text Available

2010-03-07

303

Regulation of Firing Frequency in a Computational Model of a Midbrain Dopaminergic Neuron  

UK PubMed Central (United Kingdom)

Dopaminergic (DA) neurons of the mammalian midbrain exhibit unusually low firing frequencies in vitro. Furthermore, injection of depolarizing current induces depolarization block before high...Full Text Available

2010-06-01

304

Plasticity of the cochleotopic (frequency) map in specialized and nonspecialized auditory cortices  

UK PubMed Central (United Kingdom)

Auditory conditioning (associative learning) causes reorganization of the cochleotopic (frequency) maps of the primary auditory cortex (AI) and the inferior colliculus. Focal electric stimulation...Full Text Available

2001-03-13

305

Neurobehavioral effects of power-frequency electromagnetic fields.  

UK PubMed Central (United Kingdom)

Some laboratory experiments have suggested that power-frequency electric and magnetic fields (EMF) may be capable of influencing calcium efflux from cell membranes, pineal function, and circadian rhythms....Full Text Available

1993-12-01

306

Measuring properties of impulsive low frequency noise by different measuring set up. Shogekisei teishuhaon no keisokuki ni tsuite no kento  

Energy Technology Data Exchange (ETDEWEB)

Pollution abatement measures against impulsive low frequency noises including mine blasting noise require precise measurement of sound waveforms, but no instruments have been designed for that purpose, nor commercially available. This paper describes investigations on such instruments as noise level meters currently available commercially on their instrumental characteristics using indoor experiments and field measurements. The following matters were clarified: An instrument combining a microphone with an amplifier can not determine the response from the measuring system from the respective frequency characteristics alone, and requires a discussion on the overall response from the measuring system. A preferred noise level meter would be an instrument that has the lower limit for the frequency characteristics of the microphone extended to several hertz, and measures noises without passing through a filter to interrupt ...

1991-11-25

307

Local Spatial Frequency Analysis for Computer Vision  

Science.gov (United States)

Page 1. Mt N Local Spatial Frequency Analysis N for Computer Vision N John Krumm and Steven A. Shafer CMU-RI-TR-90-1 1 JUNO0 8 199 0 ...

1990-05-01

308

Inhibited spontaneous emission by a Rydberg atom  

Science.gov (United States)

Spontaneous radiation by an atom in a Rydberg state is inhibited by use of parallel conducting planes to eliminate the vacuum modes at the transition frequency. Spontaneous radiation emission is observed to turn off abruptly at the cutoff frequency of the waveguidelike structure, and the natural lifetime is measured to increase by a factor of at least 20.

1985-11-11

309

Influence of the Atmosphere on a Rubidium Clock's Frequency ...  

Science.gov (United States)

... Figure 3 shows on-orbit (ie, vacuum) frequency aging rates for Milstar rubidium (Rb) clocks, GPS Block IIR Rb clocks, and GPS Block IIA Rb clocks. ...

2007-11-01

310

Frequency of ocular metastases in patients dying of cancer in eye bank populations.  

UK PubMed Central (United Kingdom)

AIMS: To examine the frequency of intraocular metastases in patients who had died of cancer, in an eye bank and necropsy population sample. METHODS: The first group included 302 cancer cases received...Full Text Available

1996-02-01

311

Frequency analysis of daily rainfall in Han River basin based on regional L-moments algorithm  

Energy Technology Data Exchange (ETDEWEB)

At-site and regional frequency analyses of annual maximum 1-, 2-, and 3-days rainfall in Han River basin was performed and compared based on the regional L-moments algorithm. To perform regional frequency analysis, Han River basin was subdivided into 3 sub-basins such as South Han River, North Han River, and downstream regions. For each sub-basin, the discordancy and homogeneity tests were performed. As the results of goodness of fit tests, lognormal model was selected as an appropriate probability distribution for both South Han River and downstream regions and gamma-3 model for North Han River region. From Monte Carlo simulation, RBIAS and RRMSE of the estimated quantiles from regional frequency analysis and at-site frequency analysis were calculated and compared each other. Regional frequency analysis shows less RRMSE of the estimated quantiles than at-sites ...

2001-04-30

312

Epidemiological appraisal of studies of residential exposure to power frequency magnetic fields and adult cancers.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To appraise epidemiological evidence of the purported association between residential exposure to power frequency magnetic fields and adult cancers. METHODS: Literature review and epidemiological...Full Text Available

1996-08-01

313

Bump time-frequency toolbox: a toolbox for time-frequency oscillatory bursts extraction in electrophysiological signals  

UK PubMed Central (United Kingdom)

Backgroundoscillatory activity, which can be separated in background and oscillatory burst pattern activities, is supposed to be representative of local synchronies of neural assemblies....Full Text Available

314

Artificial neural network alarm method based on signal time-frequency characteristics  

International Nuclear Information System (INIS)

On the problem of alarm when parts are falling in nuclear power plant, the artificial neural network (ANN) alarm method based on the signal time-frequency characteristics was developed. The method was realized by the improved BP algorithm, and demonstrated with the data from simulation experiments

1998-06-01

315

Wideband Modulation and Tuning of Semiconductor Lasers ...  

Science.gov (United States)

... Tunable semiconductor lasers are essential components for links employing optical frequency modulation (OFM) for enhanced dynamic range or ...

1996-07-01

316

Vibration Transmissibility Characteristics of Occupied ...  

Science.gov (United States)

... The relatively large, low frequency multi-axis motions observed at the chest may be a contributor to discomfort in locomotive engineers. ...

2006-09-01

317

Theoretical investigation of the behavior of an acoustic metamaterial with extreme Young's modulus  

British Library Electronic Table of Contents (United Kingdom)

A mechanical model with local resonators is proposed as an acoustic metamaterial that exhibits an unusual frequency-dependent effective stiffness. If treated as an equivalent elastic solid, its effective Young's modulus can become unbounded or vanishingly small at two respective frequencies. Moreover, in a certain frequency range, the effective Young's modulus would become negative, resulting in a band gap that coincides with this frequency range. The wave attenuation behavior and mechanism are studied through numerical simulations on the acoustic metamaterial model. The capability of the metamaterial to selectively block or filter unwanted waves is demonstrated by a numerical simulation example.

2011-01-01

318

The Macro Model of the Inequality Process and The Surging Relative Frequency of Large Wage Incomes  

CERN Document Server

This paper presents a model of the dynamics of the wage income distribution.

2007-01-01

319

The Calculation and Measurement of Flexural and ...  

Science.gov (United States)

... Verheij (1980) described how the frequency domain could be exploited using cross spectral density measurements to measure the flexural ...

1996-02-01

320

Response of a magneto-rheological fluid damper subjected to periodic forcing in a high frequency limit  

British Library Electronic Table of Contents (United Kingdom)

We have explored vibrations of a single-degree of freedom oscillator with a magneto-rheological damper subjected to kinematic excitations in a high frequency limit. Using fast and slow scales decoupling procedure we derived an effective damping coefficient in the limit of high frequency excitation. Damping characteristics, as functions of velocity, change considerably especially by terminating the singular non-smoothness points. This effect was more transparent for a larger control parameter which was defined as the product of the excitation amplitude and its frequency.

2008-01-01

321

NRL Fact Book 2010  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

322

NRL Fact Book  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

323

Multi-frequency binary sequence testing at FFTF [Fast Flux Test Facility  

International Nuclear Information System (INIS)

The multi-frequency binary sequence experimental technique has been implemented at the Fast Flux Test Facility for routine surveillance activities. The frequency content of the standard rod-movement sequence has been shown to be sufficient to normalize the data at moderate frequencies. This obviates the need for auxiliary calibration measurements and provides the reactivity worth of the test control rod. Analyses of a series of tests conducted in 1986 illustrate that the rod worths inferred from the tests are consistent with zero-power measurements. Also, the dependence of the prompt feedback time constant on reactor conditions was determined.

1988-09-18

324

Large scale breeder reactor pump dynamic analyses  

Energy Technology Data Exchange (ETDEWEB)

The lateral natural frequency and vibration response analyses of the Large Scale Breeder Reactor (LSBR) primary pump were performed as part of the total dynamic analysis effort to obtain the fabrication release. The special features of pump modeling are outlined in this paper. The analysis clearly demonstrates the method of increasing the system natural frequency by reducing the generalized mass without significantly changing the generalized stiffness of the structure. Also, a method of computing the maximum relative and absolute steady state responses and associated phase angles at given locations is provided. This type of information is very helpful in generating response versus frequency and phase angle versus frequency plots.

1982-01-01

326

Effect of power supply ripple on emittance growth in the collider  

Energy Technology Data Exchange (ETDEWEB)

Power supply ripple at frequencies of 720 Hz and its harmonies is expected to affect the motion of particles in the collider. These ripple frequencies are nearly resonant with the betatron frequencies. To estimate the tolerable ripple levels, we have tracked particles through the complete nonlinear lattice for 10[sup 4] turns with ripple fed from 10 different power stations and including up to 7 different ripple frequencies. We presently estimate that relative ripple amplitudes must be below the 10[sup 8] level for there to be no significant impact on the emittance over the short term.

1993-05-01

327

Effect of power supply ripple on emittance growth in the collider  

Energy Technology Data Exchange (ETDEWEB)

Power supply ripple at frequencies of 720 Hz and its harmonies is expected to affect the motion of particles in the collider. These ripple frequencies are nearly resonant with the betatron frequencies. To estimate the tolerable ripple levels, we have tracked particles through the complete nonlinear lattice for 10{sup 4} turns with ripple fed from 10 different power stations and including up to 7 different ripple frequencies. We presently estimate that relative ripple amplitudes must be below the 10{sup 8} level for there to be no significant impact on the emittance over the short term.

1993-05-01

329

DEVELOPMENT OF KSC PROGRAM FOR INVESTIGATING AND - NASA Technical ...  

Science.gov (United States)

Aluminum electrolytic capacitors, with 1043 failures, are a good example. Also, categorization by size and voltage reveals such frequencies of occurrence as ...

330

ALUMINUM ELECTROLYTIC CAPACITORS FOR HIGH ...  

Science.gov (United States)

... Accession Number : ADD872708. Title : ALUMINUM ELECTROLYTIC CAPACITORS FOR HIGH FREQUENCY APPLICATIONS. Corporate Author : ...

1976-04-26

331

Formation of interphase layers in titanium alloys under repeated loading  

International Nuclear Information System (INIS)

Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.

332

Experimental study on the uses of SQUID magnetometers as sensitive, low-frequency eddy current probes for non-destructive materials evaluation. Final report  

International Nuclear Information System (INIS)

The results show that the SQUID device eddy current testing system is a suitable tool for NDE. Due to the high low-frequency sensitivity of the SQUID sensor, the SQUID device eddy current testing system permits lower examination frequencies than the conventional eddy current probe system. The SQUID system enhances fault detection in even deeper materials layers. (orig./MM).

1996-01-01

333

Destabilization of the hot-electron precessional mode in tandem mirrors and bumpy tori  

International Nuclear Information System (INIS)

The high-frequency precessional mode of a hot-electron-stabilized magnetic configuration has previously been shown to be stable in a window of core-plasma mass. Under conditions of frequency matching, the resulting stable negative-energy precessional wave can be destabilized by coupling to positive-energy shear-Alfven waves. Coupling is avoided when the hot-electron precession frequency exceeds the core-plasma ion gyrofrequency.

334

Performance Assessment Monitoring Plan for the Hanford Site Low-Level Burial Grounds  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy reactor-compartment ...

2006-03-30

335

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

336

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

337

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).

338

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.

339

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

340

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

341

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 ...

342

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

343

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

344

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

345

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

346

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

347

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

348

Thermal impact analysis of discharge of circulating cooling water at Daya Bay Nuclear Power Station (GNPS) and Ling'ao Nuclear Power Station (LNPS)  

International Nuclear Information System (INIS)

The circulating cooling water flowrate of GNPS and LNPS is totally about 190 m"3/s. Both stations are located on the western coast of semi-closed Daya Bay. A lot of studies concerning thermal impact of GNPS and LNPS have been carried out since 1987, including mathematical model, physical model, on-site survey and satellite remote sensing, etc. This paper describes the hydrological features of Daya Bay and discharge characteristics of circulating water of GNPS and LNPS, estimates the actual thermal impact of GNPS and LNPS, and indicates that it is advantageous for the dilution of circulating water while the two discharge channels of GNPS and LNPS are combined together towards east

2004-05-01

349

Theoretical study of the non-steady discharge at atmospheric pressure in pin-plate system and its application for ozone production  

International Nuclear Information System (INIS)

In this paper as a result of the theoretical studies and a numerical simulation we presented the following main conclusions: (i) for humid air at increasing pressure of 1.0133 10"5 Pa until 5.0665 10"5 Pa ozone concentrations during 2 centre dot 10"-"3 s become higher in 22 times. This fact we clear with structure of ozone-production reactions. In this case the harmful NO_x concentrations are 2-3 order lower than ozone one; (ii) it is shown that nitrogen is useful to ozone production in the discharge; (iii) based on ion collection we cleared increasing ignition discharge voltage at growing ozone concentrations even with low ozone concentrations.

350

The role of water and oxygen impurities on ozone production in a negative corona discharge of CO_2  

International Nuclear Information System (INIS)

The production of ozone in a negative corona discharge fed by carbon dioxide with embedded traces of oxygen and water has been studied. The presence of traces of oxygen in both pure and dry CO_2 leads to an increase in nascent ozone concentrations. In contrast, traces of water vapour (0-800 ppm) are shown to rapidly suppress ozone concentrations with the largest decreases being observed at lowest gas pressures in the discharge (300 Torr). The presence of water vapour did not considerably affect the electrical properties of negative dc corona suggesting that a chemical process is responsible for the ozone loss. We have shown that the addition of water up to a concentration of 1500 ppm has only a marginal effect on the processes of ozone formation but the catalytic cycle of ozone destruction involving OH radicals can be the reason for observed decrease in the total ozone concentration with increasing water concentration.

2007-11-07

351

Study of epileptiform activity in cerebral ganglion of mud crab Scylla serrata  

British Library Electronic Table of Contents (United Kingdom)

An attempt is made to induce in mud crab (Scylla serrata) epileptiform activities that resemble the generalized epileptic seizures. Cerebral ganglion of crab was exposed in situ, to a convulsant drug pentylenetetrazole (PTZ) 100?mM, for induction of seizures. Also, crabs were pretreated with antiepileptic drug viz sodium valproate (120??mol/l) to inhibit epileptiform activities. The surface electrical discharges of cerebral ganglion were recorded using Unkelscope (MIT, USA) in control as well as experimental animals. The cerebral ganglion of crab showed a pattern of high cerebral electrical discharges after PTZ treatment compared to control. The sodium valproate promoted sedative action in control and prevented PTZ-mediated epileptiform discharges. Glutamate and GABA contents in cerebral g...

2011-01-01

352

Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film  

Science.gov (United States)

In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water, and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.

2004-04-01

353

Rapid detection of drugs in biofluids using atmospheric pressure chemi/chemical ionization mass spectrometry  

British Library Electronic Table of Contents (United Kingdom)

We have demonstrated that, with simple pH adjustment, volatile drugs such as methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), ketamine, and valproic acid could be analyzed rapidly from raw biofluid samples (e.g. urine and serum) without dilution, or extraction, using atmospheric pressure ionization. The ion source was a variant type of atmospheric pressure chemical ionization (APCI) that used a dielectric barrier discharge (DBD) to generate the metastable helium gas and reagent ions. The sample solution was loaded in a disposable glass pipette, and the volatile compounds were purged by nitrogen gas to be reacted with the metastable helium gas. The electrodes of the DBD were arranged in such a way that the generated glow discharge was confined within the discharge tub...

2009-01-01

354

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

Energy Technology Data Exchange (ETDEWEB)

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

1983-01-01

355

Hydrogen-oxygen PEM regenerative fuel cell development at Nasa Glenn Research Center  

British Library Electronic Table of Contents (United Kingdom)

The closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) at Nasa Glenn Research Center has successfully demonstrated closed-cycle operation at rated power for multiple charge/discharge cycles. During the charge cycle the RFC has absorbed input electrical power simulating a solar day cycle ranging from zero to 15 kWe peak, and delivered steady 5 kWe output power for periods exceeding 8 h. Orderly transitions from charge to discharge mode, and return to charging after full discharge, have been accomplished without incident. The RFC is beginning to demonstrate its potential as an energy storage device for aerospace solar power systems such as solar electric aircraft, lunar and planetary surface installations - any airless environment where minimum system weight is critical. This hard...

2006-01-01

356

Development of ozone generator by modification of the field distribution  

International Nuclear Information System (INIS)

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

2008-12-01

357

Development of ambient sampling chemi/chemical ion source with dielectric barrier discharge  

British Library Electronic Table of Contents (United Kingdom)

The development of a new configuration of chemical ionization (CI)-based ion source is presented. The ambient air containing the gaseous sample is sniffed into an enclosed ionization chamber which is of sub-ambient pressure, and is subsequently mixed with metastable species in front of the ion inlet of the mass spectrometer. Metastable helium atoms (He*) are used in this study as the primary ionizing agents and are generated from a dielectric barrier discharge (DBD) source. The DBD is powered by an AC high-voltage supply and the configuration of the electrodes is in such a way that the generated plasma is confined within the discharge tube and is not extended into the ionization chamber. The construction of the ion source is simple, and volatile compounds released from the bulky sample can...

2010-01-01

358

Development document for proposed effluent limitations guidelines and standards for synthetic-based drilling fluids and other non-aqueous drilling fluids in the oil and gas extraction point source category  

Science.gov (United States)

The purpose of this rulemaking is to amend the effluent limitations guidelines and standards for the control of discharges of certain pollutants associated with the use of synthetic-based drilling fluids (SBFs) and other non-aqueous drilling fluids in portions of the Offshore Subcategory and Cook Inlet portion of the Coastal Subcategory of the Oil and Gas Extraction Point Source Category. These proposed limitations apply to discharges or effluent generated when oil and gas wells are drilled using SBFs or other non-aqueous drilling fluids (collectively referred to simply as SBFs) in coastal and offshore regions in locations where drilling wastes may be discharged.

1999-02-01

359

Degradation of antibiotics in water by non-thermal plasma treatment.  

Science.gov (United States)

The decomposition of three ?-lactam antibiotics (amoxicillin, oxacillin and ampicillin) in aqueous solution was investigated using a dielectric barrier discharge (DBD) in coaxial configuration. Solutions of concentration 100 mg/L were made to flow as a film over the surface of the inner electrode of the plasma reactor, so the discharge was generated at the gas-liquid interface. The electrical discharge was operated in pulsed regime, at room temperature and atmospheric pressure, in oxygen. Amoxicillin was degraded after 10 min plasma treatment, while the other two antibiotics required about 30 min for decomposition. The evolution of the degradation process was continuously followed using liquid chromatography-mass spectrometry (LC-MS), total organic carbon (TOC) and chemical oxygen demand (COD) analyses. PMID:21514950

2011-04-06

360

The envelope order spectrum based on generalized demodulation time-frequency analysis and its application to gear fault diagnosis  

British Library Electronic Table of Contents (United Kingdom)

The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-...

2010-01-01

361

Nuclei with protrusions - tailed nuclei - and radiation cytogenetic markers in X-irradiated lymphocytes in vitro  

International Nuclear Information System (INIS)

The results of an investigation into tailed nuclei (TN) and features of dose dependence on frequency of the binuclear cells with TN in human lymphocyte cultures by cytogenetic block method upon X-ray radiation dose are presented. The frequencies of metaphases with dicentric and ring chromosomes are investigated concurrent with TN formed upon completion of first postradiation mitosis. Frequency of the appearance of binuclear cells with nuclei having outgrowth into the cytoplasmic space and arises after first mitosis in human lymphocyte culture is linear-square dependent on the X-irradiation at doses from 0.0 to 4.0 Gy. Positive correlation between frequency of cells with tailed nuclei and frequency of metaphases of first mitosis having dicentric and rings was established. Apparently, formation such TN is connected with dicentric and rings

362

Negative effective mass below a cut-off frequency  

CERN Document Server

Acoustic metamaterials with negative effective mass below a cut-off frequency are studied. An equivalent mass-spring structure is firstly proposed for such metamaterials, the effective mass is found to follow the Drude model: being negative below a specific frequency. The peculiar behavior is then verified by transmission experiments operating in the low-frequency regime. Inspired by the mass-spring model, we investigate the two-dimensional elastic waveguide with clamped boundaries and attribute the bandgap occurring below a critical frequency to negative effective mass density. The finding helps us to design a new acoustic Drude metamaterial, which enables shearing and bending deformations, in contrast to the membrane-type ones. Both simulation and experimental results show that the proposed metamaterial exhibits negative effective mass below 1200 Hz, thus opening broadband applications in vibration ...

2010-01-01

363

Regular frequency patterns in the classical delta Scuti star HD 144277 observed by the MOST satellite  

CERN Document Server

We present high-precision time-series photometry of the classical delta Scuti star HD 144277 obtained with the MOST (Microvariability and Oscillations of STars) satellite in two consecutive years. The observed regular frequency patterns are investigated asteroseismologically. HD 144277 is a hot A-type star that is located on the blue border of the classical instability strip. While we mostly observe low radial order modes in classical delta Scuti stars, HD 144277 presents a different case. Its high observed frequencies, i.e., between 59.9c/d (693.9 microHz) and 71.1c/d (822.8microHz), suggest higher radial orders. We examine the progression of the regular frequency spacings from the low radial order to the asymptotic frequency region. Frequency analysis was performed using Period04 and SigSpec. The results from the MOST observing runs in 2009 and 2010 were compared to each other. ...

2011-01-01

364

Terminated Exploding Wire Energy Source.  

Science.gov (United States)

By placing a discharge or 'dump' tube across an exploding bridgewire load, it is possible to by-pass the electrical energy and terminate the explosion of the wire. The dump tube is triggered by a signal derived from the energy removed from the storage cap...

1965-01-01

365

Superior energy capacity of graphene nanosheets for a nonaqueous lithium-oxygen battery.  

Science.gov (United States)

Graphene nanosheets (GNSs) were synthesized and used as cathode active materials in a nonaqueous lithium-oxygen battery. The GNSs electrode delivered an extremely high discharge capacity in comparison to carbon powders, which is attributed to its unique morphology and structure. PMID:21779551

2011-07-21

367

Report to Congress on Control of Combined Sewer Overflow in the United States.  

Science.gov (United States)

This report presents by state the status of awarded grants, requested grants, and the estimated time required to achieve required control of combined sewer overflow pollution. It also compares discharges of pollutants from treated municipal effluent with ...

1978-01-01

368

Plasma nitriding of austenitic stainless steel in N_2 and N_2/H_2 gas admixture  

International Nuclear Information System (INIS)

Plasma nitriding in glow discharge is a process of modifying surface properties of a material by which surface hardness, corrosion resistance, fatigue strength etc. of a material can be improved

2004-09-01

369

Occurrence of fecal indicator bacteria in surface waters and the subsurface aquifer in Key Largo, Florida.  

UK PubMed Central (United Kingdom)

Sewage waste disposal facilities in the Florida Keys include septic tanks and individual package plants in place of municipal collection facilities in most locations. In Key Largo, both facilities discharge...Full Text Available

1995-06-01

370

MANUAL: COMBINED SEWER OVERFLOW CONTROL  

Science.gov (United States)

This manual provides information to assist in selection and designing control measures for reducing pollutant discharges from combined sewer overflows (CSOs). he manual will be useful for municipal public works staff, design engineers, and regulatory agency staff tasked with the ...

371

J4P Evaluation of Externally Heated Pulsed MPD Thruster Cathodes  

Science.gov (United States)

twenty 350 V, 2.5 mF aluminum electrolytic capacitors with 10.8 mH inductors made of multi-strand wire. The PFN discharge was controlled using an silicon ...

372

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

Energy Technology Data Exchange (ETDEWEB)

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

1997-09-01

373

General practitioners' immediate management of men presenting with urethral symptoms.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To describe the immediate reported management, by general practitioners (GPs), of men presenting with symptoms of urethral discharge, or dysuria only. SUBJECTS: All 692 GPs in practice in...Full Text Available

1996-12-01

374

Environmental assessment for the ore mining and dressing industry. Final interim report: Revised executive summary  

Energy Technology Data Exchange (ETDEWEB)

The report summarizes the environmental significance of the priority pollutants being discharged from thirteen subcategories of the ore mining and dressing point source category. In addition, the impact of proposed effluent limitations guidelines is assessed from an environmental perspective.

1981-01-23

375

Electrochemical hydrogen storage of ball-milled MmMg{sub 12} alloy-Ni composites  

Energy Technology Data Exchange (ETDEWEB)

MmMg{sub 12}-Ni amorphous or nanocrystalline composites (Mm: Ce-rich mischmetal) were prepared through the ball-milling method, and their electrochemical hydrogen storage performance was investigated and compared with that of ball-milled CeMg{sub 12}-Ni composites. It was found that the ball-milled MmMg{sub 12}-Ni composites had larger initial discharge capacities and better high rate dischargeability. Analysis of electrochemical impedance spectra (EIS) shows that the reaction resistance and hydrogen diffusion resistance of the ball-milled MmMg{sub 12}-Ni composites are lower as a result of the decrease in Ce content, and thus can contribute to the larger discharge capacity and better high rate dischargeability. Additionally, the cycle performance of the ball-milled MmMg{sub 12}-Ni composites is better than those of the ball-milled CeMg{sub 12}-Ni composites. This may be related to the formation of a Nd ...

2010-04-15

376

Effects of atmospheric pressure on tracking failure of organic insulating materials; Yuki zetsuen zairyo no tai tracking sei ni oyobosu kiatsu no eikyo  

Energy Technology Data Exchange (ETDEWEB)

The effect of atmospheric pressure on tracking resistance of organic insulating materials were investigated in the range of 500 to 1007 hPa. The tracking resistance for Polycarbonate (PC), Modified Polyphenylene Oxide (M-PPO) and Paper Base Phenolic Resin Laminate (PL) increase with the decrease in atmospheric pressure. The scintillating discharges on these samples surface lead to the ignition. The tracking failure on these results from the ignition on the surface. For Polybutylene Terephthalate (PBT) and Polyethylene Terephthalate (PET), the tracking resistance decrease with the decrease in atmospheric pressure. The discharges observed on the these surface are the glow-like. The discharge area spreads on the surface between the electrodes at the lower pressure. The failure on this group results from the carbonization by the discharges on the surface. However, the tracking resistance for Unsaturated ...

1995-11-20

377

Effect of Wastewater Treatment Plant Effluent on Microbial Function and Community Structure in the Sediment of a Freshwater Stream with Variable Seasonal Flow?  

UK PubMed Central (United Kingdom)

We investigated the effects of wastewater treatment plant (WWTP) discharge on the ecology of bacterial communities in the sediment of a small, low-gradient stream in South Australia. The quantification...Full Text Available

2008-05-01

378

EARLY BILATERAL SENSORY DEPRIVATION BLOCKS THE DEVELOPMENT OF COINCIDENT DISCHARGE IN RAT BARREL CORTEX  

UK PubMed Central (United Kingdom)

Several theories have proposed a functional role for synchronous neuronal firing in generating the neural code of a sensory perception. Synchronous neural activity develops during a critical...Full Text Available

2009-02-25

379

Development Document for Proposed Effluent Limitations Guidelines and Standards for the Porcelain Enameling Point Source Category.  

Science.gov (United States)

This document is a technical background document for proposed regulations to limit effluent discharges to waters of the United States and introductions of pollutants into publicly owned treatment works from facilities engaged in porcelain enameling. The p...

1981-01-01

380

Decelerating burst and complex repetitive discharges in the striated muscle of the urethral sphincter, associated with urinary retention in women.  

UK PubMed Central (United Kingdom)

A type of electromyographic activity, formerly referred to as "pseudomyotonia", can be recorded from the striated muscle of the urethral sphincter using a concentric needle electrode. There are two...Full Text Available

1985-10-01

381

Characteristics of pulse corona discharge over water surface  

International Nuclear Information System (INIS)

Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO_2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona ...

2008-12-01

382

Behavior of ice covers subjected to large daily flow and level fluctuations  

Energy Technology Data Exchange (ETDEWEB)

The stability of a solid ice cover subjected to rapidly varying water levels and discharge was investigated. The support from the bank limits the stress in the ice cover and consequently bank contact must be maintained to ensure ice cover stability. An analysis was required of the stability of ice hinges, a flexible connection between a solid ice cover and the riverbank. Phase II and phase III of the research involved a field study of the Peace River, investigating the evolution of ice hinges with water level variation, from initial ice cover cracking parallel to the banks, to a fully developed hinge. A test program of midwinter discharge variations was undertaken to gather specific data and measurements of ice hinge link length, ice thickness, hinge joint behavior, riverbank geometry, and response of ice hinging to water level variation. This volume of appendices to the study presents detailed observations and comments from field notes through ...

1984-11-01

383

Associations between the clinical signs of chronic endometritis with ovarian cysts and body condition loss in German Holstein Friesian cows  

UK PubMed Central (United Kingdom)

The objective of this retrospective field study was to associate the type and smell of discharge, the size of the uterus, the ovarian and treatment status, and the time to diagnosis of animals with...Full Text Available

2009-12-01

384

Altitude Developmental Testing of the J-2S Rocket Engine in ...  

Science.gov (United States)

... C Characteristic velocity, ft/sec CCP Customer connect panel CD Discharge coefficient EBW Exploding bridgewire vi Page 10. AE DC-TR-70-150 ...

1970-06-01

385

A dry element  

Energy Technology Data Exchange (ETDEWEB)

The agglomerate for the element is made from activated charcoal powder, an electrically conducting additive and a neutral electrolyte. The activated charcoal makes up 30 to 50 percent of the weight of the agglomerate. It is a mixture of hydrophobized and unhydrophobized powder in a ratio of 85 to 70 to 15 to 30. The element has high discharge characteristics.

1983-08-11

386

Water resources data for Oklahoma, water year 1992. Volume 2. Red River Basin. Water-data report (Annual), 1 October 1991-30 September 1992  

Energy Technology Data Exchange (ETDEWEB)

Volume 2 of the water resources data for the 1992 water year for Oklahoma consists of record of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes or reservoirs; and water levels of ground-water well. The report contains discharge records for 136 gaging stations; stage and contents for 31 lakes or reservoirs; water quality for 50 gaging stations. Also included are 61 partial-record or miscellaneous streamflow stations and 28 ground-water sites.

1993-04-01

387

Symmetric Surface Waves in Cylindrical Waveguide Structures Filled by Radially Non-uniform Collisional Plasma  

International Nuclear Information System (INIS)

This report is devoted to the investigation of the influence of electron collisions and radial non-uniformity of plasma density on phase characteristics, spatial attenuation and wave field structure of slow symmetric electromagnetic waves that propagate along cylindrical waveguide structure. It has been shown that collision rate and radial non-uniformity of plasma density for various parameters of waveguide structure and dielectric affect essentially on the wave characteristics and consequently, on the parameters of gas discharge that is sustained by this wave. The results obtained are of large importance for the construction of the theory of gas discharges that are sustained by the surface electromagnetic waves.

2006-01-01

388

Recovery of cesium in the hydrogen negative ion sources  

Energy Technology Data Exchange (ETDEWEB)

Cesium recovery from the polluted layers in the 1/3 scale hydrogen negative ion source for LHD-NBI system has tested. It was found, that the cesium recovery can be produced by additional discharges as from the cesium layer, aged by tungsten and residual gas, so as from the cesium layers, polluted by an occasional water leak. The highest cesium recovery to NI production was produced by a xenon arc, while glow discharge and arcing in hydrogen were less effective. The mechanism of recovery is the ejection of cesium from the underlying enriched layer by the arc and its transport to the surface. (author)

1999-12-01

389

Plasma nitriding of low alloy steels at floating and cathodic potentials  

International Nuclear Information System (INIS)

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

2008-08-15

390

On-line partial discharge measurements and off-line dielectric spectroscopy measurements of six 115 kV XLPE cable systems  

Energy Technology Data Exchange (ETDEWEB)

This paper reported on a study in which partial discharge (PD) measurements were performed on 6 underground transmission cable circuits to determine the effectiveness of PD measurements on fluid fill cables. The cables were between 37 and 56 years old. PD activity was detected from the terminations of H11L and H3L Cable 2. However, for cables from H3L Basin TS to Mill Street junction, PD activity was detected originating from within the main cable insulation.

2009-07-01

391

Modeling of an electrically rechargeable alkaline zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

A numerical model has been developed to simulate the charging and discharge behaviour of an electrically rechargeable alkaline zinc-air battery. Further a galvanostatic experiment including three charge/discharge cycles has been performed. The cell voltages, the Zn electrode potentials versus a Zn reference, and the O{sub 2} electrode potentials versus a Zn reference calculated with the model are in fairly good agreement with the corresponding experimental data. The model is expected to be useful for zinc-air battery design and for analysis of experimental data. (author)

2003-03-01

392

Ion-plasma nitriding of the alloyed steel using a low pressure arc plasma generator  

International Nuclear Information System (INIS)

A study is made into microhardness and structure of coatings on various system steels (37G2S, 25Kh5M, R6M5), obtained by ion nitriding in a low pressure (10"-"1 Pa) arc discharge plasma. A comparison of properties is accomplished for steels nitrided in an arc gas discharge and in a furnace. It is stated that ion-plasma nitriding in an arc gas plasma generator is an efficient method of alloy steels hardening which allows changing the structure and increasing the hardness of a surface layer up to rather great depth

2006-12-01

393

Ion nitriding of Armco iron in various glow discharge regions  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the first results of a study of plasma nitriding in various regions of a d.c. glow discharge, i.e. on the cathode, on the anode, and on a substrate isolated from the cathode and anode (at plasma potential). The results obtained reveal differences in the growth kinetics and surface morphology of the nitriding layers, depending on the region where the nitriding process took place. The aim of this work was to study the role of low temperature plasma in the plasma nitriding process. The processes were carried out in an apparatus for plasma treatment with a hot anode. (orig.)

1993-10-01

394

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

International Nuclear Information System (INIS)

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

2009-06-01

395

Generation of microwaves and hard X-rays in a flash X-ray tube  

Energy Technology Data Exchange (ETDEWEB)

High interelectrode voltage peaks have been observed simultaneously with the emission of hard X-ray bursts from a flash X-ray tube. The magnitude of the voltage peaks may exceed twice the initial charging voltage. It has also been observed that the discharge emits bursts of X-and P-band microwaves radiation which are coincident with the emission of the hard X-ray bursts. The results indicate that the microwaves and X-rays have a common origin in discharge plasma movements and an acceleration model for electrons in the plasma is presented as one possible explanation of the observed phenomena.

1982-01-01

396

Electrical properties of airborne nanoparticles produced by a commercial spark-discharge generator  

International Nuclear Information System (INIS)

A nanoparticle generator based on the principle of electrical discharge (PALAS GFG-1000) was used to produce nanoparticles of different chemical natures. The fractions of electrically neutral particles were then measured by means of a Spectrometre de Mobilite Electrique Circulaire (SMEC, i.e. radial-flow mobility analyzer) for different operating conditions. The experimental results were compared with the theoretical values calculated from the Fuchs extended charge equilibrium model for spherical particles and agglomerates. For the smallest particles (below 20 nm), the deviations observed remain below 10%, and tend towards 20% for larger particles (over 35 nm).

2010-08-01

397

Discharging-ionization of tellurium in nitric acid electrolytes in the presence of tartrate ions  

Science.gov (United States)

The authors investigated the influence of tartaric acid, which possesses complex-forming properties. In order to establish the optimum system of possible refinement of tellurium, the authors study the kinetics of both the cathodic and the anodic processes. The investigation of processes of discharging-ionization of tellurium from nitric acid electrolytes in the presence of tartrate ions showed the possibility of preparing a nitric-tartaric acid electrolyte which can be used for commercial purposes and from which a high-purity raffinate was obtained from technical tellurium.

1986-03-20

398

Computer modeling of electrical performance of detonators  

Energy Technology Data Exchange (ETDEWEB)

An empirical model of detonator electrical performance which describes the resistance of the exploding bridgewire (EBW) or exploding foil initiator (EFI or slapper) as a function of energy, deposition will be described. This model features many parameters that can be adjusted to obtain a close fit to experimental data. This has been demonstrated using recent experimental data taken with the cable discharge system located at Sandia National Laboratories. This paper will be a continuation of the paper entitled ``Cable Discharge System for Fundamental Detonator Studies`` presented at the 2nd NASA/DOD/DOE Pyrotechnic Workshop.

1995-05-01

399

Aspiration cover for the loading site of a belt conveyer  

Energy Technology Data Exchange (ETDEWEB)

An aspiration cover is proposed for the site of loading a belt conveyer including a housing arranged above the belt conveyer in whose cover there is an aspiration sleeve and a discharge chute from the upper wall and a guide having a cushioning plate on the lower end. It is distinguished by the fact that in order to improve the effectiveness of removing dust by decreasing the volume of aspirated air, the cover between the aspiration sleeve and the upper wall of the loading chute is convex in the inside of the housing and has a smooth connection to the upper wall of the discharge chute turned towards the cushioning plate.

1982-01-01

400

A marine compartment model for collective dose assessment of liquid radioactive effluents  

International Nuclear Information System (INIS)

A compartment model is described which is currently used by the Ministry of Agriculture, Fisheries and Food to calculate collective radiation exposure due to liquid radioactive wastes discharged to sea from UK nuclear sites. Collective dose is a useful indicator of the radiological impact of a disposal practice and is one of the quantities needed to show compliance with the ICRP system of dose limitation. The model has been used for the purposes of the Sizewell Inquiry to predict the collective radiation exposure from reactor operation at Sizewell and, on the basis of current Sellafield experience, correlations between dose and discharge for disposals of fuel reprocessing wastes. (author).

1982-01-01

401

The effect of frequency and temperature on the formation of nitrided layers and surface characteristics in the plasma nitrided stainless steel  

Energy Technology Data Exchange (ETDEWEB)

This work was initiated to examine the effect of frequency and treatment temperature on the formation of nitrided layers and surface characteristics during plasma nitriding. Plasma nitriding experiments were performed with 316L austenitic stainless steel at the temperatures 400 .deg. C and 500 deg. C using a pulsed d.c. plasma with various frequencies in an atmosphere of N{sub 2}-H{sub 2} gas mixture. The microstructure and thickness of the nitrided layer and morphology of the nitrided surface were investigated using OM, SEM, XRD, EDS and AFM. XRD patterns revealed that the surface layer formed at 400 deg. C consisted of S phase only and CrN+Fe{sub 4}N nitrides at 500 .deg. C and no change of phase composition with frequency was observed. The compound layer thickened slightly with increased frequency. Also, the surface roughness increased as the frequency of the pulsed plasma ...

1999-04-01

402

Improvement of PLL algorithm for the LEP Q-meter  

CERN Document Server

The PLL (Phase Locked Loop) has two modes: search mode and locking mode. The mode is determined by how far apart the internal frequency is from the external frequency. When the internal - and exter nal frequencies are close, the PLL is in locking mode. While locking on the external frequency, the PLL can largely be expressed as a linear term superimposed with a small "noise" term. We can t herefore calculate a transfer function that will completely describe the performance of the PLL apart from the precision, which is determined by the noise term. Two ideas are presented on how to re duce the noise term. The first idea is to compensate the noise term with an equal value of opposite sign. This completely removes the noise when the PLL locks on a steady frequency. Unfortunately it can not be used for the LEP Q-meter which is plagued by the presence of satellite ...

1998-01-01

403

High-frequency electrostatic waves near Earth's bow shock  

International Nuclear Information System (INIS)

Electrostatic wave measurements from the Active Magnetospheric Particle Tracer Explorer Ion Release Module have been used to investigate the wave modes and their possible generation mechanisms in the Earth's bow shock and magnetosheath. It is demonstrated that electrostatic waves are present in the bow shock and magnetosheath with frequencies above the maximum frequency for Doppler-shifted ion acoustic waves, yet below the plasma frequency. Waves in this frequency range are tentatively identified as electron beam mode waves. Data from 45 bow shock crossings are then used to investigate possible correlations between the electrostatic wave properties and the near-shock plasma parameters. The most significant relationships found are anticorrelations with Alfven Mach number and electron beta. Mechanisms which might produce electron beams in the shock and magnetosheath are discussed in terms of the ...

404

Frequency-domain analysis of sound pressure oscillation in natural convective subcooled boiling system and its regime recognition  

International Nuclear Information System (INIS)

The dynamical signals of sound pressure oscillation in natural convective subcooled boiling system are obtained by using computer data acquisition technique. Through frequency-domain analysis of typical dynamical data, combined with study on the acquired time series of sound pressure, are observed and explained. The time-frequency phenomena, such as the onset of shock wave, frequency doubling relation of sound pressure, combination of sound frequency spectrum peaks etc., which describe the characteristics of natural convective subcooled boiling system are presented. Furthermore, based on frequency spectra of sound pressure, related eigen vectors are defined and established and with dynamical clustering method, regime recognition for the dynamical process of system is carried out. Results of recognition are consistent with that of qualitative analysis of time series, which is of ...

1998-12-01

405

Vibration experiment for a three-loop PWR reactor building  

Energy Technology Data Exchange (ETDEWEB)

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

1983-12-01

406

Spontaneous radiation of an electron beam in a free-electron laser with a quadrupole wiggler  

Energy Technology Data Exchange (ETDEWEB)

A calculation is presented of spontaneous radiation emitted by an electron beam passing through a continuously rotating quadrupole magnetic undulator. It is shown that radiation spectrum emitted in forward direction of beam propagation has four peaks, corresponding to four betatron frequencies. Utilizing the Madey theorem, a stimulated emission is calculated and presented as gain versus frequency curves, for different values of the quadrupole magnetic field. A free-electron laser operating at two or three radiation frequencies with a quadrupole magnetic wiggler is suggested.

1986-09-01

407

Magnetic fluctuation measurement in Sino United Spherical Tokamak plasma  

International Nuclear Information System (INIS)

To investigate the magnetic fluctuations and for further transport study, the poloidal and radial magnetic field measurement is conducted on the Sino United Spherical Tokamak (SUNIST). Auto-power spectral density indicates that the magnetic fluctuation energy mainly concentrates in the frequency region lower than 10 kHz. The magnetic field oscillations, which are characterized by harmonic frequencies of 40 kHz, are observed in the scrape-off layer; by contrast, in the plasma core, the magnetic fluctuations are of Gaussian type. The time-frequency profiles show that the poloidal magnetic fluctuations are temporally intermittent. The autocorrelation calculation indicates that the fluctuations in decorrelation time vary between the core and the edge. (authors)

2007-07-01

408

H-point phonon in molybdenum: Superlinearized augmented-plane-wave calculations  

International Nuclear Information System (INIS)

Local-density-approximation calculations of the H-point phonon frequency of molybdenum were carried out using a new superlinearized augmented-plane-wave basis. The calculated frequency is in quite good agreement with experiment. This indicates that the effect of the many-body renormalization of the electronic states near the Fermi energy on this frequency is smaller than previously suggested. The superlinearized basis and its use to circumvent computational difficulties associated with extended semicore states such as the 4p state of molybdenum is described.

409

A study on the development of hypo-stoichiometric Zr-based hydrogen storage alloys with ultra-high capacity for anode material of Ni/MH secondary battery  

Energy Technology Data Exchange (ETDEWEB)

Some hypo-stoichiometric Zr-based Laves phase alloys were prepared and studied from a viewpoint of discharge capacity for electrochemical application. After careful alloy design of ZrMn{sub 2}-based hydrogen storage alloys through changing their stoichiometry while substituting or adding some alloying elements, the Zr(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} alloy reveals relatively good properties with regard to hydrogen storage capacity, hydrogen equilibrium pressure and electrochemical discharge capacity. In order to improve the discharge capacity and rate-capability, Zr is partially replaced by Ti. The discharge capacity of Zr{sub 1-x}Ti{sub x}(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} (x=0.0, 0.2, 0.3, 0.4, 0.6) alloy electrodes at 30 C reaches a maximum value and decreases as the Ti fraction increases. In view of electrochemical and thermodynamic characteristics, the occurrence of a maximal ...

2000-08-10

410

Vitamins and sport.  

UK PubMed Central (United Kingdom)

In a double blind test on 40 men and women high performance fencers the influence of a multivitamin-electrolyte-preparation on reaction time, hit-frequency and neuromuscular irritability was determined....Full Text Available

1978-06-01

411

Vibratory Dynamics of Flow-Excited Struts in Water  

Science.gov (United States)

... The lateral cross spectral density measurements are normalized on the autospectrum. Frequency is normalized on r3 , and we take Uc _" 0.7 U0 . ...

1973-12-01

412

Use frequency of traditional Chinese medicine in Taiwan  

UK PubMed Central (United Kingdom)

BackgroundUse of Traditional Chinese medicine (TCM), an important category of complementary and alternative medicine (CAM), has increased substantially in Western countries during...Full Text Available

414

To Possibility of Usage of FMW Plasma Heating Scenarios in the ICR Frequency Range in the Torsatron Reactor  

International Nuclear Information System (INIS)

The problem of fast wave plasma heating in reactor-torsatron at the ICRF range in scenarios, optimal for fusion reactor, is numerically studied.

2006-01-01

416

Studies on ball screw type damper with flyball governor, 1st report  

International Nuclear Information System (INIS)

The forced nonlinear vibration and its stability of a single-degree-of-freedom system with a ball screw type damper which is composed of a ball screw, a flywheel and a flyball governor are discussed theoretically. The results are compared with a linear solution and the experimental results. The effect of vibration isolation of the damper is also discussed. Numerical examples are given for several ratios of the natural frequencies in the primary system to the governor. It is demonstrated that, when the natural frequency ratio is chosen suitably, the damper is effective in suppressing the resonance of the primary system. The amplitude response curve of the primary system is approximately equal to the linear solution except in the vicinities of the natural frequencies of the primary system and the governor, and is stable except in the vicinity of the natural frequency of the governor. (author).

1986-01-01

417

State II Dissociation Element Formation Following Activator Excision in Maize  

UK PubMed Central (United Kingdom)

Active Activator (Ac) elements undergo mutations to become nonautonomous Dissociation (Ds) elements at a low frequency. To understand...Full Text Available

2007-10-01

418

Silicon MOS inductor  

Energy Technology Data Exchange (ETDEWEB)

A device made of amorphous silicon which exhibits inductive properties at certain voltage biases and in certain frequency ranges in described. Devices of the type described can be made in integrated circuit form.

1981-01-01

419

SPACEWARN Bulletin 682 - the NSSDC! - NASA  

Science.gov (United States)

Oct 1, 2010 ... AEHF 1 is the first of four Advanced Extremely High Frequency (AEHF) satellites that will replace the earlier Milstar system. The AEHF ...

420

Respiratory disease in foundry workers.  

UK PubMed Central (United Kingdom)

A survey was carried out in a steel foundry in Brisbane to evaluate the nature and frequency of respiratory symptoms and to assess ventilatory function. The foundry used many moulding processes including...Full Text Available

1985-02-01

421

Resonant frequencies and Q factors of dielectric parallelepipeds by measurement and by FDTD  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the measurement and computation of the resonant frequencies and the associated Q factors of dielectric parallelepipeds made of high-permittivity, low-loss ceramic materials. Each resonance peak is measured separately with a fine frequency step. A curve-fitting method is used to accurately estimate the resonant frequency and 3 dB bandwidth from the somewhat noisy measured data. The finite-difference time-domain method is used to compute the initial portion of the backscattered field due to a Gaussian pulse plane wave. The time response is then extended to zero value by Prony`s method. The measured and computed data is compared for a parallelepiped resonator of permittivity 37.84.

1994-12-31

422

Prestin and high frequency hearing in mammals  

UK PubMed Central (United Kingdom)

Recent evidence indicates that the evolution of ultrasonic hearing in echolocating bats and cetaceans has involved adaptive amino acid replacements in the cochlear gene prestin. A substantial...Full Text Available

2011-03-01

423

Placebo effect in the treatment of duodenal ulcer  

UK PubMed Central (United Kingdom)

AimsTo assess whether frequency of placebo administration is associated with duodenal ulcer healing.MethodsA systematic literature...Full Text Available

1999-12-01

424

Parametric Modeling of Low-Frequency Water-Vapor-Induced ...  

Science.gov (United States)

indicated for the phase spectral density measurements; how- ever, Ref. 7 provides a very tentative estimate of : ORW ~ 2 ><10"'(RW); Ta = 1000 seconds ...

425

Neurocysticercosis, a Persisting Health Problem in Mexico  

UK PubMed Central (United Kingdom)

BackgroundThe ongoing epidemiological transition in Mexico minimizes the relative impact of neurocysticercosis (NC) on public health. However, hard data on the disease frequency...Full Text Available

429

High frequency breakdown voltage  

Energy Technology Data Exchange (ETDEWEB)

This report contains information about the effect of frequency on the breakdown voltage of an air gap at standard pressure and temperature, 76 mm Hg and O{degrees}C, respectively. The frequencies of interest are 47 MHz and 60 MHz. Additionally, the breakdown in vacuum is briefly considered. The breakdown mechanism is explained on the basis of collision and ionization. The presence of the positive ions produced by ionization enhances the field in the gap, and thus determines the breakdown. When a low-frequency voltage is applied across the gap, the breakdown mechanism is the same as that caused by the DC or static voltage. However, when the frequency exceeds the first critical value f{sub c}, the positive ions are trapped in the gap, increasing the field considerably. This makes the breakdown occur earlier; in other words, the breakdown voltage is lowered. As the frequency increases ...

1992-03-01

430

High Temperature Superconducting Compounds  

Science.gov (United States)

... Voltage noise power spectral density measurements as a function of temperature, frequency, current, and magnetic field on DyBa2Cu3O7.x (DBCO ...

1992-11-30

431

George C. - NASA Technical Reports Server  

Science.gov (United States)

Indicated inertial navigation error and required update frequency. phasing, and times). Docking Phase. Range; range rate. Clock angle; clock angle rate ...

432

Frequency-Domain Optical Mammogram  

Science.gov (United States)

... where i is the wavelength index (ranging from 1 to 4), while Esb and FHb02 are the molar extinction coefficients of deoxy-hemoglobin and oxy ...

2002-10-01

433

Focal fits during chlorambucil therapy  

UK PubMed Central (United Kingdom)

An elderly man receiving chlorambucil for chronic lymphatic leukaemia developed focal fits. The onset and frequency were dose related. There was no evidence of metabolic disturbance or of meningeal...Full Text Available

1979-11-01

435

Epidemiology of exposure to electromagnetic fields: An overview of the recent literature. (Reannouncement with new availability information)  

Energy Technology Data Exchange (ETDEWEB)

Increased concern about potential health problems related to exposure to nonionizing electromagnetic fields (EMF) has occurred recently. The most recent epidemiological studies have dealt mainly with effects of extremely low frequency EMF on fetal development and cancer. This paper summarizes noteworthy aspects or recent reviews and studies in this area of research. There has been increased concern recently about potential health problems related to exposure to nonionizing electromagnetic fields (EMF). Although some questions have been raised concerning exposure to radiofrequency radiation (at frequencies up to 300 GHz), the major focus has been on fields of extremely low frequency (especially 60 Hz). The most recent epidemiologic studies have dealt mainly with effects of extremely-low-frequency EMF on fetal development and with the initiation or promotion of cancer.

1991-12-31

436

Electromagnetic fields and public health.  

UK PubMed Central (United Kingdom)

A review of the literature is provided for the topic of health-related research and power frequency electromagnetic fields. Minimal evidence for concern is present on the basis of animal and plant research....Full Text Available

1987-11-01

437

Dishonest signalling in a fiddler crab.  

UK PubMed Central (United Kingdom)

Animal communication theory predicts that low-frequency cheating should be common in generally honest signalling systems. However, perhaps because cheats are designed to go undetected, there are few...Full Text Available

2000-04-07

438

Dielectric behaviour of emeraldine base polymer?ZnO nanocomposite film in the low to medium frequency  

British Library Electronic Table of Contents (United Kingdom)

Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...

2011-01-01

439

Control of linear accelerator noise in the Los Alamos free-electron laser (FEL)  

International Nuclear Information System (INIS)

FELs require tight control of the amplitudes and phase of the fields in two linear accelerator tanks to obtain stable lasing. The accelerator control loops must establish constant, stable, repeatable amplitudes and phases of the rf fields and must have excellent bandwidth to control high-frequency noise components. A model of the feedback loops has been developed that agrees well with measurements and allows easy substitution of components and circuits, thus reducing breadboarding requirements. The model permits both frequency and time-domain analysis. The accelerator control scheme and model are described and the control of noise in feedback loops is discussed, showing how low-frequency-noise components (errors) can be corrected, but high-frequency-noise components (errors) are actually amplified by the feedback circuit. Measurements of noise in both open- and closed-loop modes is shown and comparison ...

1986-09-01

440

CBSD Version 2 Component Models of the IR Celestial ...  

Science.gov (United States)

... 1-sigma ZOHF pixel-to-plxel statistical fluctuations ... Spatial frequency filtering shows distinct bands, but miss ... LOS emissivity at the point of closest ...

1990-12-07

441

C:\\Data\\My Documents\\NDA 21228 Peds web final final final Lisa  

Science.gov (United States)

... Increased frequency of psychiatric/behavioral disorders, including aggressive behavior, seen in children treated with tolterodine. ...

442

Approximate method for the determination of the response frequency of pipe whip. [With fluid flowing in the pipe at different velocities  

Energy Technology Data Exchange (ETDEWEB)

An approximate analysis based on the virtual work technique, which was used to determine the effect of fluid velocity on the response frequency of a simply supported pipe, resulted in the following conclusions: (1) the critical fluid velocity at which the system becomes statically unstable is 129.5 ft/s; (2) the natural frequency of the pipe decreases as the fluid velocity increases; (3) higher flow rates increase the dynamic coupling of the system, making it much more susceptible to external excitation; (4) as the critical frequency approaches zero and the fluid velocity approaches the critical value, the amplitude becomes greater (though in an actual pipe, damping effects will limit the amplitude somewhat); and (5) the virtual work technique is a convenient method for approximating solutions to most non-linear vibration problems, giving results that are satisfactory for engineering-design purposes.

1980-05-01

443

Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 in the muscular dystrophies.  

UK PubMed Central (United Kingdom)

Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 are responsible for a subset of the muscular dystrophies. In this study we aim to characterise the nature and frequency of abnormalities...Full Text Available

1998-05-01

444

AN/TAC-1 Telephone Battery Supply  

Science.gov (United States)

... C14 and C15 are special aluminum electrolytic capacitors manufactured by Cornell-Dubilier and designed for high-frequency capability, long life ...

1987-02-01

445

3-D depth migration via McClellan transformations  

Energy Technology Data Exchange (ETDEWEB)

Three-dimensional seismic wavefields may be extrapolated in depth, one frequency at a time, by two-dimensional convolution with a circularly symmetric, frequency- and velocity-dependent filter. This depth extrapolation, performed for each frequency independently, lies at the heart of 3-D finite-difference depth migration. The computational efficiency of 3-D depth migration depends directly on the efficiency of this depth extrapolation. McClellan transformations provide an efficient method for both designing and implementing two-dimensional digital filters that have a particular form of symmetry, such as the circularly symmetric depth extrapolation filters used in 3-D depth migration. Given the coefficients of one-dimensional, frequency- and velocity-dependent filters used to accomplish 2-D depth migration, McClellan transformations lead to a simple and efficient algorithm for 3-D depth migration. 21 ...

1990-01-01

446

 

UK PubMed Central (United Kingdom)

An epidemiological study about mastitis in French dairy herds, supported by an ecopathological survey is described. The aim of this work was to explain variations of the annual frequencies of...Full Text Available

1986-03-01

447

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

448

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

449

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

450

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

451

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

452

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

453

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

454

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

455

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

456

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

457

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

458

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

459

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

460

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

461

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

462

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

463

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

464

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

465

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

466

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.).

467

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

468

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)

469

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

470

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

471

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

472

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).

473

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

474

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

475

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.

476

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

477

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

478

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

479

Modelling transport of water and solutes in future wetlands in Forsmark  

Energy Technology Data Exchange (ETDEWEB)

The Forsmark area consists of a number of natural wetlands. As a part of the evaluation of wetlands in the safety assessment for the area, possible future wetlands are being studied with respect to hydrology and transport mechanisms. A sensitivity analyses is performed to point out the governing parameters for the wetland hydraulics. The analysis of future wetlands is carried out using the hydrological model system Mike SHE. Mike SHE has been used to describe the near-surface hydrology for a regional model area in Forsmark. Three types of areas have been chosen. Today's lake Bolundfjaerden is because of its shallow depth likely to develop into a mire in the future. As it is situated in the downstream part of the regional model area, the runoff to the lake from upstream surface water system is significant. Lake Eckarfjaerden is situated in the upstream part of the catchment at a higher altitude and with a smaller inflow. Lake Puttan is situated above a planned layout of the ...

2006-03-15

480

Solid state secondary battery with lithium ion conductive solid electrolyte, Li3PO4-Li2S-SiS2; Li3PO4-Li2S-SiS2 kei kotai denkaishitsu wo mochiita zenkotai richiumu niji denchi  

Energy Technology Data Exchange (ETDEWEB)

Powder mold type solid state battery was fabricated, and positive electrode compounding ratio and the battery characteristics were studied. The current density depended greatly on the TiS2 content of positive electrode material, and the current density showed maximum value of 800 {mu}A/cm{sup 2} at a TiS2 content of 40 wt%. This composition is expected to be the best to provide better charge-discharge characteristics. The rate capability of TiS2 is dominated by Li{sup +} ion in positive electrode. Further, the diffusion of lithium ion is greatly dominated by TiS2 in positive electrode, compounding ratio of solid state electrolyte and its particle size. Results of charge-discharge characteristics studied for various charge-discharge current densities revealed that the rate capability of TiS2 was more than 50% for a current density of less than 254 {mu}A/cm{sup 2}, and this battery system proved the possibility of high rate ...

1995-01-05

481

Radiant emittance of xenon positive column discharges  

Energy Technology Data Exchange (ETDEWEB)

An embodiment of a mercury-free fluorescent lamp combines a low pressure rare gas discharges with a phosphor having a quantum efficiency grater than one. The choice of the rare gas depends on a number of factors, one of which is the resonance transition energy. Less demand is placed the quantum efficiency of the phosphor for a lower energy resonance photon. Xenon has the lowest energy resonance transition of the stable rare gases at 8.5 eV (147 nm) and thus is a good candidate to study. The usefulness of a xenon-based discharge depends on the radiant emittance of the discharge at the resonance wavelength of 147 nm. The radiant emittance from a low pressure xenon positive column discharge is measured using two independent techniques. The first relies on the measurement of the resonance level density using absorption techniques. The effective decay rate of the resonance level is calculated using radiation ...

1994-12-31

482

Properties of surface layers on titanium alloy produced by thermo- chemical treatments under glow discharge conditions  

Energy Technology Data Exchange (ETDEWEB)

The recent rapid progress in surface treatment techniques dictates that the titanium alloys should have an improved resistance to frictional wear without any loss of their high corrosion resistance. These requirements can be satisfied by producing surface layers of specified microstructure and phase composition. The present paper describes a modification of the plasma discharge nitriding treatment of titanium alloys, i.e. the glow discharge-assisted oxycarbonitriding, which by introducing oxygen, nitrogen and carbon into the surface zone of the layer [a Ti(NCO) type layer] improves its useful properties, primarily the resistance to frictional wear and the resistance to corrosion [T. Wierzchon, J. Sobiecki, Vacuum, 44 (1993) 975; T. Wierzchon et al., in: G. Hecht, F. Richter, J. Hahn (Eds.), Thin Films, DGM Informationgesellschaft, Germany, 1994, p. 195] [1:2]. This is because titanium shows a good affinity to oxygen, carbon and nitrogen, ...

1997-11-25

483

Impact assessment using 25 years of environmental radioactivity monitoring data at Tarapur Maharashtra site  

International Nuclear Information System (INIS)

Environmental Survey Laboratory at Tarapur, Maharashtra site carries out environmental radioactivity measurements in different matrices to evaluate the impact of operating nuclear installations. In this paper, the evaluation of data of 1983-2007 (25 years) is presented. Time trends of particulate radioactivity, correlation between "1"3"7Cs in discharge canal seawater and station discharged activity and correlation of "1"3"7Cs, "6"0Co, and "1"3"1I in marine species like Sponge and Nerita and corresponding discharged activity were carried out. Statistical analysis of environmental data of seawater and marine fish for several radionuclides, for distributions, showed that the data best fits lognormal distribution. A strong correlation between "1"3"7Cs in seawater and "1"3"7Cs in liquid waste discharge was observed (R"2 = 0.8, P = 0.000). Similarly correlation was very good for Nerita and ...

2008-07-16

484

An investigation of the origin of the electrochemical hydrogen storage capacities of the ball-milled Co-Si composites  

Energy Technology Data Exchange (ETDEWEB)

The Co-Si composites with a molar ratio of 2:1 are synthesized by ball-milling method and their potential as negative electrode materials of Ni-MH batteries is investigated. The microstructure, morphology and chemical state of the ball-milled Co-Si composites are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). XRD patterns show that the ball-milled samples for 10 and 20 h contain Co, Si and Co{sub 2}Si phases, and the ball-milled samples for 40 and 60 h are mainly amorphous Co{sub 2}Si alloys. In contrast to the high initial discharge capacity (1012 mAh/g) obtained for the sample ball-milled for 10 h, the discharge capacities of the samples ball-milled for 40 and 60 h are very low. It indicates that the hydrogen storage capacity of pure Co{sub 2}Si alloy is very low. It is found that the formation of active Co nanoparticles and Si oxidation are responsible for the high ...

2010-02-15

485

Waveguide device and method for making same  

Energy Technology Data Exchange (ETDEWEB)

A monolithic micromachined waveguide device or devices with low-loss, high-power handling, and near-optical frequency ranges is set forth. The waveguide and integrated devices are capable of transmitting near-optical frequencies due to optical-quality sidewall roughness. The device or devices are fabricated in parallel, may be mass produced using a LIGA manufacturing process, and may include a passive component such as a diplexer and/or an active capping layer capable of particularized signal processing of the waveforms propagated by the waveguide.

2007-08-14

486

Variable Frequency Microwave Synthesis of Silver Nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

Synthesis of silver nanoparticles based on a polyol process and variable frequency microwave (VFM) was investigated. Comparing to a thermal method, the reaction by VFM radiation was much faster. The effects of silver nitrate concentration, poly(N-vinylpyrrolidone) (PVP) concentration, reaction time and reaction temperature were studied. It was found that the higher concentration of silver nitrate, longer reaction time and higher temperature increased the particle size while the higher concentration of PVP decreased the particle size.

2006-02-15

487

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-12-31

488

Optical voltage reference  

Energy Technology Data Exchange (ETDEWEB)

An optical voltage reference for providing an alternative to a battery source. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function.

1992-12-31

489

Now try to explain network security  

Science.gov (United States)

Overloaded transmission lines are only part of the problem. The ability of the network to carry power is also limited by the supply of reactive power and by frequency stability. Reactive power problems must be corrected in minutes, frequency stability problems in seconds. There is no way that market forces can handle these problems. Reactive power must be supplied to all long transmission and distribution lines to compensate for the loss of reactive volt-amperes - and resulting voltage drop - in the reactance along the line`s length. 7 figs.

1996-10-01

490

Measurement of audible noise from transmission lines  

Energy Technology Data Exchange (ETDEWEB)

The audible noise produced by corona on high-voltage transmission lines has several characteristics that differentiate it from other community noises. Transmission line noise is quite broadband and has a significant high frequency content. Special instrumentation designed to measure this type of noise pollution is described. All measuring systems have the same three basic elements: a transducer, a processing device, and an output device. Recorders, microphone devices, frequency analyzers, and meteorological instrumentation are discussed.

1981-03-01

491

Limiting-dilution analysis of T cells extracted from solid human lung tissue: comparison of precursor frequencies for proliferative responses and lymphokine production between lung and blood T cells from individual donors.  

UK PubMed Central (United Kingdom)

This study evaluates the frequency and functions of immunocompetent T cells at the clonal level in solid human lung tissue versus peripheral blood. Enzymatic digestion of slices of histologically normal...Full Text Available

1988-08-01

492

Higher harmonics of spontaneous radiation of ultrarelativistic channeled particles  

International Nuclear Information System (INIS)

The case of spontaneous radiation of channeled ultrarelativistic particles is considered when the dipolarity condition is not satisfied. The change of the particle longitudinal velocity affecting the maximum radiation frequency is included. The angular and frequency characteristics of the radiation for superhigh energies are studied for the first time. It is shown that there is an optimum energy at which the radiation density is maximum. The influence of the angle at which electrons enter a crystal and of the beam divergence on the radiation is investigated. The problem of quasichanneled particle radiation and also the radiation in axis-plane transitions are considered. (author).

1980-06-01

493

Frequency of conjugative transfer of plasmid-encoded ISEcp1 - blaCTX-M-15 and aac(6')-lb-cr genes in Enterobacteriaceae at a tertiary care center in Lebanon - role of transferases  

UK PubMed Central (United Kingdom)

BackgroundThe frequency of transfer of genes encoding resistance to antimicrobial agents was determined by conjugation in ESBL-producing and/or fluoroquinolone or aminoglycoside...Full Text Available

494

Frequency evaluation of the doubly forbidden $^1S_0\\to ^3P_0$ transition in bosonic $^{174}$Yb  

CERN Document Server

We report an uncertainty evaluation of an optical lattice clock based on the $^1S_0\\leftrightarrow^3P_0$ transition in the bosonic isotope $^{174}$Yb by use of magnetically induced spectroscopy. The absolute frequency of the $^1S_0\\leftrightarrow^3P_0$ transition has been determined through comparisons with optical and microwave standards at NIST. The weighted mean of the evaluations is $\

2008-01-01

495

Fifty successful years of the Institute of Plasma Physics, Academy of Sciences of the Czech Republic  

International Nuclear Information System (INIS)

The history of the Czech Institute of Plasma Physics is highlighted. The article is structured as follows: Cyclic accelerators; Interaction of an external high-frequency field and high-temperature plasma - the tokamak; Interaction of an external high-frequency field and high-temperature plasma - pulse plasma systems; Low-temperature plasma - plasma technologies and new materials; Laser plasma - PALS; Optical diagnosis; and Teaching, conferences and international cooperation. (P.A.)

496

Fault diagnosis of rolling bearing based on cyclic spectrum density  

International Nuclear Information System (INIS)

The paper considered the vibration signals of rotating equipment as cyclo stationary signals through analyzing the features of this kind of signals. Based on the analytic method of cyclic spectrum density, the paper pointed out that the impact frequency could be extracted effectively with the help of scanning cyclic frequency domain. The validity of the method of cyclic spectrum density is proved by simulating signals and the method is applied to the diagnosis of rolling bearings. (authors)

2009-09-01

497

Evolution of the luminosity function of quasar accretion disks  

International Nuclear Information System (INIS)

Using an accretion-disk model, accretion disk luminosities are calculated for a grid of black hole masses and accretion rates. It is shown that, as the black-hole mass increases with time, the monochromatic luminosity at a given frequency first increases and then decreases rapidly as this frequency is crossed by the Wien cutoff. The upper limit on the monochromatic luminosity, which is characteristic for a given epoch, constrains the evolution of quasar luminosities and determines the evolultion of the quasar luminosity function. 22 refs.

498

A two-frequency Wiggler for a better control of a free-electron-laser dynamics  

Energy Technology Data Exchange (ETDEWEB)

In the paper is studied the physics of a free electron laser (FEL) based on a two-frequency undulator (TFU) which induces large non linear effects, especially on the spectral dynamics. These effects are analyzed in an extended formalism where the spontaneous emission, the low-gain regime and the strong-field saturation regime are studied. Numerical simulations show that the optimized TFU generates a laser field having both a large extraction efficiency and a narrow spectrum.

1991-12-31