UK PubMed Central (United Kingdom)
ObjectiveThe purpose of the study was to assess the risk of CHD associated with excess weight measured by BMI and waist circumference (WC) in two large cohorts of...Full Text Available
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
The relationship between cigarette smoking and cell damage is complicated, particularly considering the role of oxidative stress. The aim of this study was to identify the relationships among plasma nicotine metabolites, lipophilic antioxidants, and metabolic parameters in smokers and non-smokers. This cross-sectional study recruited 100 subjects who visited the Department of Family Medicine at Kaohsiung Medical University Hospital. Excluding 14 ineligible cases, 46 smokers and 40 non-smokers were enrolled. Plasma nicotine metabolites, lipophilic antioxidants (including retinol, lycopene, a-carotene, b-carotene, d-tocopherol, g-tocopherol and a-tocopherol), related metabolic parameters, and body composition (including height, weight, body mass index, body fat, and waist circumference) were...
2009-01-01
... Problem: At a glass ceramic cooktop plant, workers manually lift uncut plates of glass onto a waist-high conveyor belt, where it is then stacked ...
2011-05-13
International Nuclear Information System (INIS)
... radiation effects human populations low dose irradiation neoplasms radiation
1980-01-01
Spot size and Guoy phase invariant telescope for auto-alignment of resonant cavities
International Nuclear Information System (INIS)
We present both the theory and an experimental method to accurately set up a Guoy phase telescope, where both the output spot size and orthogonality condition are invariant to distance from the cavity beam waist. We demonstrate that Gaussian spot size measurements can be used as a diagnostic to determine the desired locations of split area photodetectors. The Guoy phase invariance is verified using the tilt-locking technique.
2004-03-07
{sup 3}He spectrum at small atmospheric depths for different geomagnetic cutoff values
Energy Technology Data Exchange (ETDEWEB)
It is carried out a calculation to determine the energy spectra of secondary {sup 3}He at small atmospheric depths. It is produced in the spallation reaction of primary helium and heavier nuclei in the overlying atmosphere. It is examined the effect of the geomagnetic cut-off on the spectral shape of the secondary {sup 3}He nuclei. The calculations are being carried out for both solar minimum and maximum periods. Results from these calculations will be presented at the Conference.
1995-09-01
Geometrically relating momentum cut-off and dimensional regularization
The $\\beta$ function for a scalar field theory describes the dependence of the coupling constant on the renormalization mass scale. This dependence is affected by the choice of regularization scheme. I explicitly relate the $\\beta$-functions of momentum cut-off regularization and dimensional regularization on scalar field theories by a gauge transformation using the Hopf algebras of the Feynman diagrams of the theories.
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The electron cyclotron resonance layer in a tokamak, {omega}={omega}{sub c}(r), is not accessible by the extraordinary wave from the low field side, because it is shielded by a cutoff layer. However, a X-mode launched with a nonzero toroidal angle propagates at the cutoff parallel to the magnetic field and has a circular polarization. Therefore it can already at the cutoff layer interact efficiency with electrons via the Doppler shifted resonance. The driven current can be substantially higher than that driven by the second harmonic X-mode. The applicability of this current drive scheme is limited to rather low values of {omega}{sub p}{sup 2}/{omega}{sub c}{sup 2}, but may be of interest for high magnetic field devices. (author)
2000-02-01
Atmospheric proton and deuterium energy spectra determination with the MASS2 experiment
Energy Technology Data Exchange (ETDEWEB)
The energy spectra of atmospheric-secondary protons and deuterium nuclei have been measured during the September 23, 1991, balloon flight of the NMSU/Wizard - MASS2 instrument. The apparatus was launched from Fort Sumner, New Mexico. The geomagnetic cutoff at the launch site is about 4.5 GV/c. The instrument was flown for 9.8 hours at an altitude of over 100,000 feet. Particles detected below the geomagnetic cutoff have been produced mainly by the interactions of the primary cosmic rays with the atmosphere. The measurement of cosmic ray energy spectra below the geomagnetic cutoff provide direct insights into the particle production mechanism and allows comparison to atmospheric cascade calculations.
1995-09-01
Energy Technology Data Exchange (ETDEWEB)
The X-ray spectra of {approx}200 AGN collected from Swift-BAT were analyzed to test the Unified Model for AGN. Specifically, the photon indices, high energy cutoffs, and reflection components of Sy1 and Sy2 were compared. Under the Unified Model, the photon indices and reflection components for Sy1 should be larger than Sy2 and the high energy cutoffs should be the same. Fitting a simple power law model to the sample spectra proved to be insufficient. The PEXRAV model fit the spectra of the Sy1 and Sy2 significantly better, indicating that a reflection component and/or high energy cutoff exists as the Unified Model expects. Using both the simple power law and PEXRAV models it was concluded that in the population studied, Sy1 had a larger photon index than Sy2, as expected by the Unified Model. For Sy1 and Sy2, the reflection components were found to be compatible, but given the large errors, this finding cannot be said to ...
2010-08-25
Natural Variation of Drug Susceptibility in Wild-Type Human Immunodeficiency Virus Type 1
UK PubMed Central (United Kingdom)
Wild-type viruses from the ViroLogic phenotype-genotype database were evaluated to determine the upper confidence limit of the drug susceptibility distributions, or “biological cutoffs,”...Full Text Available
2004-02-01
Energy Technology Data Exchange (ETDEWEB)
The optimizing criterion is assumed to be the maximum net present value of the project. The following summarizes the significant conclusions. (1) Over a large range of discount rates, mining and milling of the mineral deposit at a constant cutoff grade and a constant production rate consistently results in smaller annual discounted cash flows than the optimal schedule determined by the dynamic programming model (dpm) where the cutoff grade and mining rate are allowed to vary in response to fluctuating product price. (2) With an increasing discount rate, under the dpm the annual discounted cash flows decrease at a slower rate than if the mineral inventory is mined and milled at a constant cutoff grade and a constant production rate. (3) Cuttoff grade increases only where higher equity ore is available. Thus, to maintain the mill feed requirement, the mining rate also increases. (4) Not withstanding an anamolous mineral ...
1986-01-01
Inhibited spontaneous emission by a Rydberg atom
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
Donor deferral due to anemia: A tertiary care center-based study
UK PubMed Central (United Kingdom)
Background:The minimum hemoglobin cutoff for blood donation in India is 12.5 gm% for both male and female donors and the minimum donation interval is 3 months. Donation...Full Text Available
2011-01-01
Development of large-capacity refrigeration at 1.8 K for the Large Hadron Collider at CERN
CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an ...
1996-01-01
Energy Technology Data Exchange (ETDEWEB)
In an electromagnetic pump of the present invention for use in circulation of coolants in an LMFBR type reactor, the outer circumference of coil conductors is covered by an insulator retaining cover, and powdery or granular insulator is filled between the coil conductors and the insulator retaining cover. Upon reaching high temperature, elongation of the coil conductors by heat expansion is absorbed by movement of the particles of the powdery insulator thereby preventing excess stresses from exerting on the coil insulator constituted with the insulator retaining cover and the powdery or granular insulator and preventing generation of crackings on the coil insulator. Thus, plant stability is improved. (N.H.).
1994-05-13
Negative effective mass below a cut-off frequency
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 and noise controls.
2010-01-01
Investigating the Ultraviolet Properties of Gravity with a Wilsonian Renormalization Group Equation
We review and extend in several directions recent results on the asymptotic safety approach to quantum gravity. The central issue in this approach is the search of a Fixed Point having suitable properties, and the tool that is used is a type of Wilsonian renormalization group equation. We begin by discussing various cutoff schemes, i.e. ways of implementing the Wilsonian cutoff procedure. We compare the beta functions of the gravitational couplings obtained with different schemes, studying first the contribution of matter fields and then the so-called Einstein-Hilbert truncation, where only the cosmological constant and Newton's constant are retained. In this context we make connection with old results, in particular we reproduce the results of the epsilon expansion and the perturbative one loop divergences. We then apply the Renormalization Group to higher derivative gravity. In the case of a general action quadratic in curvature we recover, ...
2008-01-01
Study of free electron laser (FEL) using the electron storage ring 'NIJI-IV'
International Nuclear Information System (INIS)
We have constructed a racetrack-type compact electron storage ring 'NIJI-IV' for UV FEL. The ring has a hexagonal configuration with two 7.25 m-long straight sections, though its circumference is 29.6 m. A 6.3 m optical klystron (OK) for high FEL gain was installed in one of the long straight sections. The experimental setup for FEL lasing was started at the end of April 1992. The setup on the ring with the OK and the cavity mirror alignment have been completed. The FEL lasings using the NIJI-IV were accomplished at 595-589 nm on August 18, 1992 and at 488 nm on September 18, 1992. The final development target is stable FEL lasing in the UV range. (author).
Simulation of a storage ring Free Electron Laser with mapping algorithm for distribution functions
International Nuclear Information System (INIS)
A model for the simulation of the time dependent behavior and the analysis of the equilibrium of the coupled system of storage ring and Free Electron Laser (FEL) is presented. The analysis comprises both amplifier and oscillator FEL. Bunch lengthening and energy widening due to wake forces are taken into account in a self-consistent way. The method is based on a mapping algorithm for means and correlations of the electron distribution function, pioneered by K. Hirata. The evolution of the laser field in the oscillator FEL is described by K. Hirata. The evolution of the laser field in the oscillator FEL is described by supermodes. The model is used to simulate an FEL in a small 500 MeV storage ring with 100 m circumference. Typical values for the output power, spatial, and spectral characteristics of the emitted radiation are presented.
1991-05-06
Physical findings in the upper airways related to obstructive sleep apnea in men and women
British Library Electronic Table of Contents (United Kingdom)
Conclusions. There are gender differences when it comes to the risk factors for sleep apnea. Large tonsils, a high tongue and a wide uvula are risk factors for sleep apnea in men, while large tonsils and a retrognathic mandible are risk factors in women. Upper airway abnormalities including mandibular retrognathia are, however, unable to predict sleep apnea among snorers being investigated for suspected sleep apnea. Objectives. To identify gender-specific risk factors for obstructive sleep apnea and the diagnostic performance from physical upper airway examinations among snoring men and women investigated because of suspected sleep apnea. Patients and methods. The dimensions of the uvula, tonsils, velopharynx and tongue, and nasal septal deviation, mandibular position, neck circumference, ...
2007-01-01
British Library Electronic Table of Contents (United Kingdom)
The aim of this study is to clarify the relation among developmental outcome, nutritional state during the neonatal period, maturational electroencephalographic changes. Thirteen extremely low birth weight infants who completed 6- or 9-year follow-up were a subject of this study. Undernutrition was defined as enteral feeding below 100mL/kg/day at 3weeks of age. Dysmature patterns were defined as the persistence of EEG patterns 2weeks or more immature for post-conceptional age. IQ was examined at 6 and 9years of age. Body height and weight, and head circumference at 6years of age were stratified by the percentile grades. Full and verbal IQ was significantly lower in infants with undernutrition than those with normal nutrition. Among infants with undernutrition, those with persistent dysmatu...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
A concentric reducer tube, which was a part of the top exit roughing hydraulic descaler in a hot strip mill failed prematurely under working pressure. A detailed metallurgical investigation comprising physical examination, optical microscopy, scanning electron microscopy, and electron probe microanalysis was carried out to find out the genesis of the failure. Physical examination revealed cracks located symmetrically around the circumference of the tube that ran along its full length, up to the weld beads at both ends. Optical microscopy of etched samples revealed a banded ferrite-pearlite structure and the existence of forging folds near the change-in-section(160? fillets). Cracks were found to initiate from these forging folds. No structural abnormalities were found in the weld beads and...
2007-01-01
Gravity-wave insights to Bianchi type-IX universes
Energy Technology Data Exchange (ETDEWEB)
Every Bianchi type-IX universe can be interpreted as a closed Friedmann universe on which is superimposed circularly polarized gravitational waves with the longest wavelength that will fit into a closed universe. In this paper, I give a new derivation of this result based on the concept of homogeneous tensor fields on the three-sphere. Every homogeneous symmetric traceless tensor field is shown to be a longest-wavelength three-sphere harmonic. Contrary to previous authors, I show that the wavelength of these gravitational waves is one-half the circumference of the universe. In order to maintain homogeneity, the gravitational waves must all have the same polarization. There are five longest-wavelength modes for each polarization. This interpretation is an {ital exact} description that is valid for every Bianchi type-IX universe---it is in no way limited to first-order perturbations of a Friedmann universe.
1991-10-15
British Library Electronic Table of Contents (United Kingdom)
Objective To demonstrate clinical features of a patient subgroup presenting with polycystic ovary syndrome (PCOS) without polycystic ovary morphology. Design Retrospective study. Setting Hospital-based IVF center. Patient(s) In the present study, 876 PCOS patients were selected from women who visited the Reproductive Medicine Center at Shandong Provincial Hospital, Shandong University, between September 2004 and October 2006. Women with PCOS were divided into two groups based on ultrasound image: group A, PCOS patients with classic polycystic ovary (n = 800); group B, PCOS patients without polycystic ovary morphology (n = 76). The following available data were analyzed in the large cohort of women: body height, weight, waistline, hip circumference, hirsutism scores, family history, serum s...
2008-01-01
International Nuclear Information System (INIS)
We analyze the O(N) symmetric #sigma#-model in four dimensions with and without external source in the large-N approximation. We show that tachyons appear in these models only if cut-off effects are neglected. Including these effects and incorporating the triviality of the #sigma#-model, we demonstrate that no tachyon pole exists. We discuss how our results affect recent ideas to circumvent the 'no-loose-corollary' for W_L W_L scattering. (orig.).
International Nuclear Information System (INIS)
Using the experimentally determined cutoff energies of the muon-electron and the pion-electron conversion curves in a tachyon-bradyon model of the electron and the muon, the magnetic moments of these particles have been derived and found to be the Bohr magnetons identically. The tachyons, being bound to the bradyons and unable to drop below the speed of light, cause the bradyons to revolve in an orbit. It is this orbital motion of the charged bradyons that generates the magnetic moments.
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.
(Research in theoretical physics): Annual performance report, (1986)
Energy Technology Data Exchange (ETDEWEB)
Results are reported in the areas of: chiral fermions and anomalies, superstring finiteness, superstring phenomenology, spin splittings in heavy quarkonia, low-energy limits of superstring, a supersymmetric electroweak model with a light squark, scalar quark bound states, fermionic tachyons and Poincare representations, relativistic dynamics of spin-one particles and deuteron-nucleus scattering, interactions involving higher spin massless particles, and classical action at a distance theories which contain a cutoff. (LEW)
1986-01-01
Energy Technology Data Exchange (ETDEWEB)
A computed tomography (CT) cut-off for differentiating neoplastic lesions (polyps/carcinoma) from normal colon in contrast-enhanced CT colonography (CTC) relating to the contrast phase and lesion size is determined. CT values of 64 colonic lesions (27 polyps <10 mm, 13 polyps {>=}10 mm, 24 carcinomas) were determined by region-of-interest (ROI) measurements in 38 patients who underwent contrast-enhanced CTC. In addition, the height (H) of the colonic lesions was measured in CT. CT values were also measured in the aorta (A), superior mesenteric vein (V) and colonic wall. The contrast phase was defined by xA + (1 - x)V using x as a weighting factor for describing the different contrast phases ranging from the pure arterial phase (x=1) over the intermediate phases (x=0.9-0.1) to the pure venous phase (x=0). The CT values of the lesions were correlated with their height (H), the different phases (xA + (1 - x)V) and the ratio [xA + (1 - x)V]/H. The CT ...
2004-12-01
Nuclear Data Sheets for A = 166
Energy Technology Data Exchange (ETDEWEB)
Nuclear structure data pertaining to all known A = 166 nuclides (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt) have been compiled and evaluated, and incorporated into the ENSDF data file. This evaluation for A = 166 supersedes the previous publication (E.N. Shurshikov and N.V. Timofeeva, Nuclear Data Sheets 67, 45 (1992) (literature cutoff date 1 October 1990)) and the revision by C.M. Baglin of {sup 166}W (literature cutoff data 16 April 2000). It includes literature available by 1 March 2008. Subsequent to the previous evaluation, {sup 166}Gd has been observed for the first time and the first observations of excited states in {sup 166}Tb, {sup 166}Re, {sup 166}Os and {sup 166}Ir have been reported: also, knowledge of collective structure in {sup 166}Dy. {sup 166}Ho, {sup 1676}Er, {sup 166}Tm, {sup 166}Yb, {sup 166}Lu, {sup 166}Hf, and {sup 166}Ta has been considerably expanded. However, the structure suggested here for {sup ...
2008-02-06
Entropy, confinement, and chiral symmetry breaking
This paper studies the way in which confinement leads to chiral symmetry breaking (CSB) through a gap equation. We argue that entropic effects cut off infrared singularities in the standard confining effective propagator $1/p^4$, which should be replaced by $1/(p^2+m^2)^2$ for a finite mass $m\\sim K_F/M(0)$ [$M(0)$ is the zero-momentum value of the running quark mass]. Extension of an old calculation of the author yields a specific estimate for $m$. This cutoff propagator shows semi-quantitatively two critical properties of confinement: 1) a negative contribution to the confining potential coming from entropic forces; 2) an infrared cutoff required by gauge invariance and CSB itself. Entropic effects lead to a proliferation of pion branches and a $\\bar{q}q$ condensate, and contribute a negative term $\\sim -K_F/M(0)$ to the effective pion Hamiltonian allowing for a massless pion in the presence of positive kinetic energy and string energy. ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
The fluxes of atmospheric electrons, positrons, positive and negative muons and negative pions have been determined using the NMSU Wizard-MASS2 balloons-borne instrument. The instrument was launched from Fort Sumner, New Mexico, (geomagnetic cut-off about 4.5 GV/c) on september 23, 1991. The flight lasted 9.8 hours and remained above 100.000 ft. Muons and negative pions were observed and their momenta were determined. Since these particles are not a part of the primary component, the measurement of their fluxes provides information regarding production and propagation of secondary particles in the atmosphere. Similarly, observations of electrons and positrons well below the geomagnetic cut-off provides insight into electromagnetic cascade processes in the upper atmosphere. In addition, the determination of the energy spectra of rare particles such as positrons can be used for background subtraction for cosmic ray experiments gathering data ...
1995-09-01
CARM-klystron amplifier for accelerator applications
International Nuclear Information System (INIS)
We consider the possibility of a cyclotron-autoresonance-maser (CARM) klystron configuration for accelerator applications as an alternative to the gyroklystron amplifier. The potential advantages, compared to gyroklystrons, include: 1) comparable efficiencies at lower values of the electron beam pitch ratio #alpha#, which should improve the beam quality and make the device substantially more stable against the excitation of parasitic mode, 2) operation far from cutoff, which should reduce the fields at cavity walls, allowing higher power operation, and 3) operation at lower magnetic fields for the same cyclotron harmonic number. However, there are two significant issues associated with the design of efficient, high-power CARMs. First, because of the higher value of k_Z, compared to gyroklystrons, CARMs are substantially more sensitive to parallel velocity spread (pitch-angle spread). Second, conventional cavities support a variety of ...
2001-05-31
British Library Electronic Table of Contents (United Kingdom)
Summary Background Systematic screening for liver fibrosis in heavy-drinking patients is a challenge. Aims To assess Fibroscan for non-invasive diagnosis of asymptomatic liver fibrosis in alcohol abuse patients, to determine diagnostic liver stiffness cut-off values and to compare performance of Fibroscan with seven non-invasive laboratory tests. Methods One hundred and three alcoholic patients were studied. Liver fibrosis was staged by METAVIR system. Fibroscan, Fibrotest, Fibrometer, Hepascore, APRI, PGA, PGAA and hyaluronic acid tests were performed. Liver stiffness cut-offs were determined using receiver-operating characteristic (ROC) curves. Results Liver stiffness was correlated with fibrosis (r = 0.72, P < 0.014), with median at 5.7, 6.3, 8.4, 15 and 47.3 kPa for F0 (n = 8), F1 (n =...
2008-01-01
A widely tunable continuous-time LPF for a direct conversion DBS tuner
Energy Technology Data Exchange (ETDEWEB)
A continuous-time 7th-order Butterworth Gm-C low pass filter (LPF) with on-chip automatic tuning circuit has been implemented for a direct conversion DBS tuner in 0.35 mum SiGe BiCMOS technology. The filter's -3 dB cutoff frequency f{sub 0} can be tuned from 4 to 40 MHz. A novel on-chip automatic tuning scheme has been successfully realized to tune and lock the filter's cutoff frequency. Measurement results show that the filter has -0.5 dB passband gain, +-5% bandwidth accuracy, 30 nV/Hz{sup 1/2} input referred noise, -3 dBVrms passband IIP3, and 27 dBVrms stopband IIP3. The I/Q LPFs with the tuning circuit draw 13 mA (with f{sub 0} = 20 MHz) from 5 V supply, and occupy 0.5 mm{sup 2}.
2009-02-15
Reactor fuel cladding tube with excellent corrosion resistance and method of manufacturing the same
International Nuclear Information System (INIS)
The present invention provides a fuel cladding tube having an excellent corrosion resistance and thus a long life, and a suitable manufacturing method therefor. Namely, in the fuel cladding tube, the outer circumference of an inner layer made of a zirconium base alloy is coated with an outer layer made of a metal more corrosion resistant than the zirconium base alloy. Ti or a titanium alloy is suitable for the corrosion resistant metal. In addition, the outer layer can be coated by a method such as vapor deposition or plating, not limited to joining of the inner layer material and the outer layer material. Specifically, a composite material having an inner layer made of a zirconium alloy coated by the outer material made of a titanium alloy is applied with hot fabrication at a temperature within a range of from 500 to 850degC and at a fabrication rate of not less than 5%. The fabrication method includes any of extrusion, rolling, drawing, and casting. As the ...
1993-07-14
International Nuclear Information System (INIS)
Steam Generator (SG) tubes in PWR plant are periodically inspected using eddy current testing (ECT) method. In Japan, bobbin coil type dual function probe is used for full length inspection, but the detectability for circumferential crack is very poor, and to improve detectability for circumferential crack and supplement regular ECT, various kinds of multi segment eddy current probes and multi transducer ultrasonic testing (UT) method have been developed. ECT probes are constructed of multiple surfaceriding special winding differential type coils and UT probe consists of 16 transducers which are spaced equally around the probe circumference for 360deg wall coverage. Both of those EC and UT probes are designed effective to detect circumferential crack. On the other hand, various kinds of laboratory induced circumferential cracks have been made and destroyed to prove the detectability of these probes. (author).
1991-08-01
International Nuclear Information System (INIS)
Purpose: To effectively cool the reactor core in a steam atmosphere by upwardly directing several of spray nozzles attached to a ring header thereby increasing the flying distance of the spray. Constitution: Ring headers in two upper and lower stages are disposed above the outer circumference of a reactor core and each of the ring headers is mounted with spray nozzles. Among the spray nozzles, at least several nozzles mounted to the ring header at the lower stage are directed such that the center axis for each of the nozzle is raised above the horizontal axis and other several nozzles are mounted with the nozzle center axis directed downwardly from the horizontal axis. Accordingly, even if collapsing phenomenon occurs in the jetting stream due to the condensation in the steams that forms the operation atmosphere of the reactor core spray cooling device, a sufficient amount of emergency cooling water can be distributed over the entire reactor core region since the ...
1983-03-09
Energy Technology Data Exchange (ETDEWEB)
When a rotary excavator is operated at locations where there is artesian water, the aquiclude is fractured under pressure of the artesian water upon the penetration of the pile tip through the aquiclude. Since the equipment is provided with a gap for the reduction of friction between the casing and the excavation face, soil and sand near the pile tip burst forth out of the ground together with underground water through the casing or along the outer circumference of the casing. The newly contrived method introduced here is a double pipe process, in which a large casing (2.0m in diameter) is driven until it lands on the aquiclude, water is injected into the casing for the creation of equilibrium between the artesian head and the head in the casing, and finally a casing as large as the pile (1m in diameter) to be installed is used for the excavation of the artesian water section. Since February, 1996, 4 systems/16 legs have been operated for the installation of 96 ...
1998-11-05
Energy Technology Data Exchange (ETDEWEB)
An analyser for detecting explosives has at least one neutron source and a plurality of gamma ray detectors. An article to be analysed is moved adjacent the source and detectors and is subjected to neutrons which generate gamma rays from any nitrogen in the article. The gamma rays are detected and analysed to determine the nitrogen concentration within the article. In order to achieve an area of uniform detection there are a plurality of detectors equidistant both from the or each source and from the article to be analysed. In order to avoid a decrease in sensitivity away from the source(s) and detectors there may be a second opposing array of source(s) and detectors on the opposite side of the article. For greatest uniformity of detection, a source in one array opposes a detector in the other array and vice versa. Transmission of radiation from the analyser is kept at safe levels by enclosing the analyser within shielding which includes shield members extending from a trolley or other ...
1991-03-13
Array coil probe: Final report
Energy Technology Data Exchange (ETDEWEB)
Nuclear steam generator tubes have become flawed in ways that challenge conventional eddy current probes. In response to the shortcomings of conventional probes, array probes have been developed to improve measurement capabilities. However, the commercially available array probes have exhibited several weaknesses that offset the advantages and limit the applications in steam generator inspections. A primary weakness is the relatively high rate of probe failure coupled with the high unit cost for each probe. This can be costly for a utility in the time lost for probe replacement and increased radiation exposure in addition to the probe costs. Other weaknesses which make array probes undesirable for routine use are: poor mechanical and electrical characteristics; difficulty in operation and calibration; and incomplete coverage of the tube circumference. Several prototype array probes have been built to address the weaknesses of the commercially available array ...
1987-03-01
Analysis of natural convection in narrow annular gaps of LMFBR
International Nuclear Information System (INIS)
The natural convection characteristics of gas in a vertical narrow annular gap which had its bottom opened to high temperature fluid and its upper shielding exposed to low temperature sealant have been evaluated from simulated fluid experiments using water and from calculations using the three-dimensional thermal hydraulic analysis computer code THERVIS-III. The following results were obtained: (1) The critical Rayleigh number which represented the limit of convection generation increased as the aspect ratios #epsilon#_1 (height/circumference) and #epsilon#_2 (height/gap distance) increased. (2) The flow pattern along the circumferential direction was seen to depend more strongly on the radiant heat from the side wall, rather than the aspect ratios #epsilon#_1 and #epsilon#_2. (3) The temperature difference along the circumferential direction in the annular gap obtained from the calculation code coincided with that obtained from experiments within #+-# 10 %, by ...
Studies of a Poenitz-type black neutron detector as a neutron flux monitor
Energy Technology Data Exchange (ETDEWEB)
A black neutron detector of novel design has been constructed and tested as a neutron flux monitor. The neutron time-of-flight (TOF) technique was used to measure the zero degree neutron spectrum from a subnanosecond pulsed proton beam on a thick metallic lithium target. We describe the detector, discuss the shielding arrangement and electronics, determine the low-energy cut-off. We calculate the efficiency, show spectra and compare measured zero degree differential cross-section of the {sup 7}Li(p, n{sub 0}){sup 7}Be reaction with recommended published cross-sections. (orig.).
1997-04-01
Production of secondary Deuterium in the atmosphere at various latitudes
Energy Technology Data Exchange (ETDEWEB)
Secondary deuterium in the atmosphere are produced in interactions by primary cosmic rays. The shape of their energy spectrum depends on the primary cosmic ray spectrum incident at the top of the atmosphere. At high energies, the spectral shape depends on the primary spectrum of helium and heavy nuclei. However, at very low energies, specially below the geomagnetic cut-off, the spectral shape depends on the evaporation and recoil processes and hence almost independent of the spectral shape of the primary radiation. It is undertaken a calculation of the secondary deuterium spectrum at small atmospheric depths at various latitudes and the results will be presented.
1995-09-01
Large-scale baryon isocurvature inhomogeneities
Energy Technology Data Exchange (ETDEWEB)
Big bang nucleosynthesis constraints on baryon isocurvature perturbations are determined. A simple model ignoring the effects of the scale of the perturbations is first reviewed. This model is then extended to address the claim that large amplitude perturbations will collapse, preventing their baryons from contributing to the observed baryon density. It is found that baryon isocurvature perturbations are constrained to provide only a slight increase in the density of baryons in the universe over the standard homogeneous model. In particular, it is found that models which rely on power laws and the random phase approximation for the power spectrum are incompatible with big bang nucleosynthesis unless an ad hoc, small-scale cutoff is included. {copyright} {ital 1995 The American Astronomical Society.}
1995-09-01
Ground level cosmic ray observations
Energy Technology Data Exchange (ETDEWEB)
Cosmic rays at ground level have been collected using the NMSU/Wizard - MASS2 instrument. The 17-hr observation run was made on September 9. 1991 in Fort Sumner, New Mexico, Usa. Fort Sumner is located at 1270 meters a.s.l., corresponding to an atmospheric depth of about 887 g/cm{sup 2}. The geomagnetic cutoff is 4.5 GV/c. The charge ratio of positive and negative muons and the proton to muon ratio have been determined. These observations will also be compared with data collected at a higher latitude using the same basic apparatus.
1995-09-01
Comparison of Atmospheric Dispersion Models Between PHWR and PWR
International Nuclear Information System (INIS)
The radiation dose and the atmospheric dispersion for Pressurized Heavy Water Reactors (PHWR) are based on the CAN/CSA N288.2-M91 standards: for Pressurized Water Reactor (PWR) on the NRC Regulatory Guide 1.145. There are some differences between in the methodologies used in the standards, including the atmospheric dispersion model, the release height, the temperature lapse rate, the cutoff condition. This paper reports on a comparison of standards for atmospheric dispersion models of PHWRs and PWRs in order to determine which one is the more conservative. The comparison between PHWR and PWR for atmospheric dispersion factors and radiation doses confirms that there are no big differences
2010-10-01
Characterization of flame front surfaces in turbulent premixed methane/air combustion
Energy Technology Data Exchange (ETDEWEB)
A detailed experimental investigation of the application of fractal geometry concepts in determining the turbulent burning velocity in the wrinkled flame regime of turbulent premixed combustion was conducted. The fractal dimension and cutoff scales were determined for six different turbulent flames in the wrinkled flame regime, where the turbulence intensity, turbulent length scale, and equivalence ratio were varied. Unlike previous reports, it has proved possible to obtain the fractal dimension and inner and outer cutoffs from individual flame images. From this individual data, the pdf distributions of all three fractal parameters, along with the distribution of the predicted increase in surface area, may be determined. The analysis of over 300 flame images for each flame condition provided a sufficient sample size to accurately define the pdf distributions and their means. However, the predicted S{sub T}/S{sub L}, calculated using fractal ...
1995-06-01
British Library Electronic Table of Contents (United Kingdom)
Abstract Aims: The aim of this study was to examine whether metabolic syndrome (MS) is associated with periodontitis in a representative sample of Korean adults, who were involved in the Fourth Korea National Health and Nutrition Examination Survey (KNHANES). Materials and Methods: A total of 7178 subjects over the age of 19 years who participated in KNHANES were examined. MS was defined as the definition proposed by the National Cholesterol Education Program Adult Treatment Panel III and the abdominal obesity cut-off line based on Korean Society for the Study of Obesity. The periodontal status was assessed by the Community Periodontal Index. Multivariate logistic regression analysis was carried out adjusting for the sociodemographics, oral health behaviours and status, and health behaviou...
2011-01-01
Structure of Mgn and Mg n + clusters up to n = 30
British Library Electronic Table of Contents (United Kingdom)
We present structure calculations of neutral and singly ionized Mg clusters of up to 30 atoms, as well as Na clusters of up to 10 atoms. The calculations have been performed using density functional theory (DFT) within the local (spin-)density approximation, ion cores are described by pseudopotentials. We have utilized a new algorithm for solving the Kohn-Sham equations that is formulated entirely in coordinate space and, thus, permits straightforward control of the spatial resolution. Our numerical method is particularly suitable for modern parallel computer architectures; we have thus been able to combine an unrestricted simulated annealing procedure with electronic structure calculations of high spatial resolution, corresponding to a plane-wave cutoff of 954 eV for Mg. We report the geo...
2011-01-01
Signatures of extra dimensions at e{gamma} and {gamma}{gamma} colliders
Energy Technology Data Exchange (ETDEWEB)
The authors study the processes {gamma}e {r{underscore}arrow} {gamma}e and {gamma}{gamma} {r{underscore}arrow} {gamma}{gamma}, in the context of the proposal for Weak Scale Quantum Gravity (WSQG) with large extra dimensions. With an ultraviolet cutoff M{sub S} {approximately} 1 TeV for the effective gravity theory, the cross sections obtained for these processes at the Next Linear Collider (NLC), with the e{gamma} an {gamma}{gamma} options, deviate from the predictions of the Standard Model significantly. The results suggest that, for typical proposed NLC energies and luminosities, the predictions of WSQG can be tested in the range 1 TeV {approx{underscore}lt} M{sub S} {approx{underscore}lt} 10 TeV, making e{gamma} an {gamma}{gamma} colliders important tools for probing WSQG.
2000-01-26
On Finite Noncommutativity in Quantum Field Theory
We consider various modifications of the Weyl-Moyal star-product, in order to obtain a finite range of nonlocality. The basic requirements are to preserve the commutation relations of the coordinates as well as the associativity of the new product. We show that a modification of the differential representation of the Weyl-Moyal star-product by an exponential function of derivatives will not lead to a finite range of nonlocality. We also modify the integral kernel of the star-product introducing a Gaussian damping, but find a nonassociative product which remains infinitely nonlocal. We are therefore led to propose that the Weyl-Moyal product should be modified by a cutoff like function, in order to remove the infinite nonlocality of the product. We provide such a product, but it appears that one has to abandon the possibility of analytic calculation with the new product.
2010-01-01
New technology for purging the steam generators of nuclear power plants
British Library Electronic Table of Contents (United Kingdom)
A technology for removal of undissolved impurities from a horizontal steam generator using purge water is developed on the basis of a theoretical analysis. A purge with a maximal flow rate is drawn off from the zone with the highest accumulation of sludge in the lower part of the steam generator after the main circulation pump of the corresponding loop is shut off and the temperatures of the heat transfer medium at the inlet and outlet of the steam generator have equilibrated. An improved purge configuration is used for this technology; it employs shutoff and regulator valves, periodic purge lines separated by a cutoff fixture, and a D y 100 drain union as a connector for the periodic purge. Field tests show that the efficiency of this technology for sludge removal by purge water is severa...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
Abstract Lyme neuroborreliosis (LNB) is a serious but treatable disease. The diagnosis of LNB poses a challenge to clinicians, and improved tests are needed. The C6-peptide ELISA is frequently used on serum but not on cerebrospinal fluid (CSF). Data on the sensitivity of the C6-peptide ELISA in CSF in patients suffering from LNB have been conflicting. Serum-CSF pairs from 59 LNB patients, 36 Lyme non-neuroborreliosis cases, 69 infectious meningitis/encephalitis controls and 74 neurological controls were tested in a C6-peptide ELISA. With the optimal cut-off of 1.1, the sensitivity of the C6-peptide ELISA for LNB patients in CSF was 95%, and the specificity was 83% in the Lyme non-neuroborreliosis patients, 96% in the infectious controls, and 97% in the neurological controls. These results ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
The purpose of this study was to validate through natural exposure a cut-off level of varicella zoster IgG as protective against infection with varicella zoster virus (VZV). Laboratory testing to determine VZV immune status of pregnant women exposed to varicella is recommended. Quantitative assays are now available which are sensitive and specific. More than 200 consecutive requests for screening in pregnant patients with recent varicella contacts were followed-up by questionnaire. DiaSorin LIAISON and VZV time resolved fluorescence immuno assay (VZV TRFIA) were used to measure VZV antibody level. One hundred fifty out of 209 (72%) questionnaires were returned; 14 patients developed varicella, 129 did not and seven were not known. Patients who had been given VZIG and developed varicella on...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
This paper is concerned with the study of the Electrorheological RayleighTaylor instability (ERTI) at the interface between a densely packed saturated poorly conducting couple stress porous layer accelerated by a lighter poorly conducting couple stress fluid in a thin shell in the presence of a transverse electric field and laser radiation. A simple theory based on fully developed flow approximations is used to derive the dispersion relation for the growth rate of ERTI. The cutoff and the maximum wave numbers and the corresponding maximum frequencies are obtained. It is shown that the effects of couple stress parameter and the electric field reduce the growth rate considerably compared to a non-conducting fluid in the absence of an electric field. These are favorable to control the surface...
2011-01-01
International Nuclear Information System (INIS)
The contribution of exchange processes (heavy stripping and substitution) into the amplitude of the 25-30 MeV #alpha#-particle elastic scattering by "1"2C and "4"0Ca nuclei is examined taking into account the distortion of plane waves of initial and finite particles. The eikonal approximation is used for accounting for distortions. The matrix elements of exchange processes are calculated. The results of calculations show that the Wronskian cutoff radii are close to those which have been obtained for calculation of exchange processes in the plane-wave approximation. The moduli of the values defining the contribution of exchange processes to the total S matrix are plotted. Also presented are Argand diagrams and angular distributions for both reactions. It has been established that the account for exchange processes improves the agreement of theoretical curves with the experiment in the whole range of angles, as compared with the optical model.
AlxGa1-xN/GaN multi-quantum-well ultraviolet detector based on p-i-n heterostructures
British Library Electronic Table of Contents (United Kingdom)
We report on characterization of a set of AlGaN/GaN multiple-quantum-well (MQW) photodetectors. The model structure used in the calculation is the p-i-n heterojunction with 20 AlGaN/GaN MQW structures in i-region. The MQW structures have 2nm GaN quantum well width and 15nm AlxGa1-xN barrier width. The cutoff wavelength of the MQW photodetectors can be tuned by adjusting the well width and barrier height. Including the polarization field effects, on increasing Al mole fraction, the transition energy decreases, the total noise increases, and the responsivity has a red shift, and so the detectivity decreases and has a red shift.
2009-01-01
Acoustic cloaking in two dimensions: a feasible approach
Energy Technology Data Exchange (ETDEWEB)
This work proposes an acoustic structure feasible to engineer that accomplishes the requirements of acoustic cloaking design recently introduced by Cummer and Schurig (2007 New J. Phys. 9 45). The structure, which consists of a multilayered composite made of two types of isotropic acoustic metamaterials, exactly matches the conditions for the acoustic cloaking. It is also shown that the isotropic metamaterials needed can be made of sonic crystals containing two types of material cylinders, whose elastic parameters should be properly chosen in order to satisfy (in the homogenization limit) the acoustic properties under request. In contrast to electromagnetic cloaking, the structure here proposed verifies the acoustic cloaking in a wide range of wavelengths; its performance is guaranteed for any wavelength above a certain cutoff defined by the homogenization limit of the sonic crystal employed in its fabrication.
2008-06-15
Acoustic cloaking in two dimensions: a feasible approach
International Nuclear Information System (INIS)
This work proposes an acoustic structure feasible to engineer that accomplishes the requirements of acoustic cloaking design recently introduced by Cummer and Schurig (2007 New J. Phys. 9 45). The structure, which consists of a multilayered composite made of two types of isotropic acoustic metamaterials, exactly matches the conditions for the acoustic cloaking. It is also shown that the isotropic metamaterials needed can be made of sonic crystals containing two types of material cylinders, whose elastic parameters should be properly chosen in order to satisfy (in the homogenization limit) the acoustic properties under request. In contrast to electromagnetic cloaking, the structure here proposed verifies the acoustic cloaking in a wide range of wavelengths; its performance is guaranteed for any wavelength above a certain cutoff defined by the homogenization limit of the sonic crystal employed in its fabrication.
2008-06-01
Ab initio pseudopotential calculations of carbon impurities in Si
Energy Technology Data Exchange (ETDEWEB)
Ab initio planewave pseudopotential method is used to study carbon diffusion and pairing in crystalline silicon. The calculation is performed with a 40 Ry planewave cutoff and 2x2x2 special k-point sampling with a supercell of 64 atoms. It is found that substitutional carbon attracts interstitial Si forming a <001> C interstitial with a large binding energy of 1.45 eV. The interstitial carbon is mobile and can migrate with a migration energy of 0.5 eV. The interstitial carbon can bind further to another substitutional carbon forming a substitutional carbon-interstitutional carbon pair with a binding energy of 1.0 eV. This model is used to understand the effect of high C concentration on the transient enhanced diffusion in Si.
1997-11-01
Energy Technology Data Exchange (ETDEWEB)
We describe the growth, fabrication, and characterization of an ultraviolet (UV) photoconductive detector based on In{sub x}Al{sub y}Ga{sub 1-x-y}N quaternary alloy that is lattice matched to GaN. The detector consisted of 0.1 {mu}m In{sub x}Al{sub y}Ga{sub 1-x-y}N alloy grown on 0.5-1.0 {mu}m GaN epilayer by metalorganic chemical vapor deposition. With varying indium concentration, the cut-off wavelength of the In{sub x}Al{sub y}Ga{sub 1-x-y}N detectors could be varied to the deep UV range. The most important and intriguing result is that the responsivity of the In{sub x}Al{sub y}Ga{sub 1-x-y}N quaternary alloy exceeded that of AlGaN alloy of a comparable cutoff wavelength by a factor of five. This makes the nitride quaternary alloy very important material for solar blind UV detectors applications particularly in the deep UV range where Al rich AlGaN alloys have problems with low quantum efficiency and cracks due in part to lattice mismatch ...
2000-08-07
Photoresponsivity of ultraviolet detectors based on In_xAl_yGa_1_-_x_-_yN quaternary alloys
International Nuclear Information System (INIS)
We describe the growth, fabrication, and characterization of an ultraviolet (UV) photoconductive detector based on In_xAl_yGa_1_-_x_-_yN quaternary alloy that is lattice matched to GaN. The detector consisted of 0.1 #mu#m In_xAl_yGa_1_-_x_-_yN alloy grown on 0.5-1.0 #mu#m GaN epilayer by metalorganic chemical vapor deposition. With varying indium concentration, the cut-off wavelength of the In_xAl_yGa_1_-_x_-_yN detectors could be varied to the deep UV range. The most important and intriguing result is that the responsivity of the In_xAl_yGa_1_-_x_-_yN quaternary alloy exceeded that of AlGaN alloy of a comparable cutoff wavelength by a factor of five. This makes the nitride quaternary alloy very important material for solar blind UV detectors applications particularly in the deep UV range where Al rich AlGaN alloys have problems with low quantum efficiency and cracks due in part to lattice mismatch with GaN. The advantages of ...
2000-08-07
Energy Technology Data Exchange (ETDEWEB)
We study the surface and interface roughness of a two-liquid film system using neutron reflectometry. The middle phase and bottom phase are extracted from a three-phase microemulsion containing 2 wt% non-ionic surfactant C{sub 10}E{sub 4}, 81 wt% D{sub 2}O and 17 wt% octane (C{sub 8}H{sub 18}). The system is formed by spreading a few drops of the middle phase of the microemulsion on the bottom phase of the microemulsion. The middle phase does not wet the bottom phase, but demixes to form a top octane-water mixture layer with a thickness of {proportional_to}580 A. The mean surface roughness of the system is found to be 7 A but the data are insensitive to interface roughness. An extended capillary wave model for a two-liquid-film system is derived to account for the coupling between the surface and interface. The dispersion relation yields two fundamental modes. In a calculation of mean-square roughness (left angle {zeta}{sup 2} right angle {sup 1/2}) a high-k-cutoff ...
1996-04-01
Energy Technology Data Exchange (ETDEWEB)
A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin with 1 M HCl (for milk samples a second ...
2007-04-18
Energy Technology Data Exchange (ETDEWEB)
To establish the optimum barium-based reduced-laxative tagging regimen prior to CT colonography (CTC). Ninety-five subjects underwent reduced-laxative (13 g senna/18 g magnesium citrate) CTC prior to same-day colonoscopy and were randomised to one of four tagging regimens using 20 ml 40%w/v barium sulphate: regimen A: four doses, B: three doses, C: three doses plus 220 ml 2.1% barium sulphate, or D: three doses plus 15 ml diatriazoate megluamine. Patient experience was assessed immediately after CTC and 1 week later. Two radiologists graded residual stool (1: none/scattered to 4: >50% circumference) and tagging efficacy for stool (1: untagged to 5: 100% tagged) and fluid (1: untagged, 2: layered, 3: tagged), noting the HU of tagged fluid. Preparation was good (76-94% segments graded 1), although best for regimen D (P = 0.02). Across all regimens, stool tagging quality was high (mean 3.7-4.5) and not significantly different among regimens. The HU of layered ...
2008-01-15
Variability and spectral modeling of the hard X-ray emission of GX 339-4 in a bright low/hard state
We study the high-energy emission of the Galactic black hole candidate GX 339-4 using INTEGRAL/SPI and simultaneous RXTE/PCA data. By the end of January 2007, when it reached its peak luminosity in hard X-rays, the source was in a bright hard state. The SPI data from this period show a good signal to noise ratio, allowing a detailed study of the spectral energy distribution up to several hundred keV. As a main result, we report on the detection of a variable hard spectral feature (>150 keV) which represents a significant excess with respect to the cutoff power law shape of the spectrum. The SPI data suggest that the intensity of this feature is positively correlated with the 25 - 50 keV luminosity of the source and the associated variability time scale is shorter than 7 hours. The simultaneous PCA data, however, show no significant change in the spectral shape, indicating that the source is not undergoing a canonical state transition. We analyzed the broad band ...
2010-01-01
The infrared-dominated jet of 3C401
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 location of the synchrotron peak in the SED, resulting in a sharp ...
2005-01-01
The NIR Upgrade to the SALT Robert Stobie Spectrograph
The near infrared (NIR) upgrade to the Robert Stobie Spectrograph (RSS) on the Southern African Large Telescope (SALT), RSS/NIR, extends the spectral coverage of all modes of the visible arm. The RSS/NIR is a low to medium resolution spectrograph with broadband imaging, spectropolarimetric, and Fabry-Perot imaging capabilities. The visible and NIR arms can be used simultaneously to extend spectral coverage from approximately 3200 A to 1.6 um. Both arms utilize high efficiency volume phase holographic gratings via articulating gratings and cameras. The NIR camera is designed around a 2048x2048 HAWAII-2RG detector housed in a cryogenic dewar. The Epps optical design of the camera consists of 6 spherical elements, providing sub-pixel rms image sizes of 7.5 +/- 1.0 um over all wavelengths and field angles. The exact long wavelength cutoff is yet to be determined in a detailed thermal analysis and will depend on the semi-warm instrument cooling scheme. Initial estimates ...
2006-01-01
In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O2-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane ...
2011-04-01
Energy Technology Data Exchange (ETDEWEB)
A hose lining process, used widely for underground service structures, such as for city gas, and water and sewerage pipes, was adopted to repair interiors of underground wire raceways, and improvements were made for power cable pipe use, including long size construction, inner diameter assurance, and flame retardation. The sealing hose as a lining material consists of a fabric layer woven by warps of polybutylene terephthalate (PBT) and wefts of combined PBT fibers and glassfibers, the fabric being coated with polyurethane resin on one side. The other side of the fabric is coated with heat hardening resin made of epoxy resin as the main ingredient and aromatic amine as the hardening agent to assure close adhesion of the sealing hose onto the pipe interior. Mimic raceways were used to verify the lining material for its abrasion coefficient, mechanical strength, wear resistance, water cut-off performance, chemical resistance, and shape retention performance against ...
1991-03-25
Studies on the interaction of lidocaine with plasma proteins
Energy Technology Data Exchange (ETDEWEB)
This study sought to quantitate lidocaine's interaction with alpha-1-acid glycoprotein (AAG), human serum albumin (HSA), and AAG in the presence of HSA, and to determine the extent of displacement of lidocaine from its binding site(s) by selected cardiovascular drugs (dipyridamole, disopyramide and quinidine). Since the limited experimental work reported in this area has involved the use of a single lidocaine concentration, this study involved the evaluation of a range of lidocaine concentrations. Lidocaine interaction with plasma proteins (AAG and HSA) was studied at 37/sup 0/C using an isothermal equilibrium dialysis system and /sup 14/C-lidocaine HCl. A dialysis membrane (M.W. cutoff 12,000 to 14,000) separated the two chambers of each dialysis cell. The extent of /sup 14/C-lidocaine dialysis was studied with respect to both drug and protein concentrations. Aliquots of each chamber of each of the cells were subjected to liquid scintillation counting ...
1985-01-01
Structure of Mg$_n$ and Mg$_n^+$ clusters up to n=30
We present structure calculations of neutral and singly ionized Mg clusters of up to 30 atoms, as well as Na clusters of up to 10 atoms. The calculations have been performed using density functional theory (DFT) within the local (spin-)density approximation, ion cores are described by pseudopotentials. We have utilized a new algorithm for solving the Kohn-Sham equations that is formulated entirely in coordinate space and, thus, permits straightforward control of the spatial resolution. Our numerical method is particularly suitable for modern parallel computer architectures; we have thus been able to combine an unrestricted simulated annealing procedure with electronic structure calculations of high spatial resolution, corresponding to a plane-wave cutoff of 954eV for Mg. We report the geometric structures of the resulting ground-state configurations and a few low-lying isomers. The energetics and HOMO-LUMO gaps of the ground-state configurations are carefully ...
2011-01-01
Radial distribution of superthermal electrons measured with ECE (abstract)
International Nuclear Information System (INIS)
To aid in the study of lower hybrid current drive as a means of current profile control, the radial profile and velocity distribution of the fast current-carrying electrons and their time evolution must be known. As part of the recent effort to understand this fast electron transport, a diagnostic has been installed on PBX-M to measure the electron cyclotron emission from the fast electrons. An oblique horizontal view of upshifted cyclotron emission in the midplane can give radial as well as velocity space information about the fast electrons. Emission in X mode frequencies refracted by the right-hand cutoff is radially localized. The observed emission at a specific frequency comes only from the radial region r_t_u_r_n=#0. Emission measured by this new diagnostic has been found to be radially localized as predicted. It is also expected that localized moments of the distribution function may be obtained from these data. A superheterodyne receiver at 60--90 GHz has ...
0854-01-01
Midwave infrared type-II InAs/GaSb superlattice detectors with mixed interfaces
We report the growth and fabrication of midwave infrared InAs/GaSb strain layer superlattice (SLS) detectors. Growth of alternate interfaces leads to a reduced strain between the GaSb buffer and SLS ({delta}a{sub parallel}/a=-5x10{sup -4}), enabling the growth of active regions up to 3 {mu}m (625 periods). The structural, optical, and electrical properties of the active region were characterized using x-ray crystallography and photoluminescence, respectively. p-i-n detectors were grown using 625 periods of 8 ML (monolayer) InAs/8 ML GaSb as the active region. The {lambda}{sub cutoff} for the detectors was 4.6 {mu}m with a conversion efficiency of 32% at V{sub b}=-0.2 V. Detectivity was obtained using noise power spectral density measurements under 300 K 2{pi} field of view illumination and was equal to 5.2x10{sup 10} and 3x10{sup 10} cm Hz{sup 1/2}/W (V{sub b}=-0.02 V, T=80 K) in the white noise and 1/f noise limit (at 50 Hz)
2006-07-01
Methodology for designing air-quality-monitoring networks. 1. Theoretical aspects
Energy Technology Data Exchange (ETDEWEB)
An objective methodology is presented for determining the number and disposition of ambient air-quality stations in a monitoring network for the primary purpose of compliance with air-quality standards. The methodology utilizes a data base with real or simulated data from an air quality dispersion model for application with a two-step process for ascertaining the optimal monitoring network. In the first step, the air-quality patterns in the data base are collapsed into a single composite pattern through a figure-of-merit (FOM) concept. The most-desirable locations are ranked and identified using the resultant FOM fields. In the second step the network configuration is determined on the basis of the concept of spheres of influence (SOI) developed from cutoff values of spatial-correlation coefficients between potential monitoring sites and adjacent locations. The minimum number of required stations is then determined by deletion of lower-ranked stations whose ...
1986-01-01
Kaluza-Klein Effects on Higgs Physics in Universal Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
We examine the virtual effects of Kaluza-Klein (KK) states on Higgs physics in universal extra dimension models. We study the partial widths {Lambda}{sub h{yields}gg}, {Lambda}{sub h{yields}{gamma}{gamma}}, and {Lambda}{sub h{yields}{gamma}Z}, which are relevant for Higgs production and detection in future collider experiments. These interactions occur at one loop in the Standard Model, as do the KK contributions. We find that the deviations induced by the KK exchanges can be significant; for one extra dimension, the gg {yields} h production rate is increased by 10% - 85% for the mass of the first KK state in the range 500 {approx}> m{sub 1} {approx}> 1500 GeV, a region untested by current direct search and precision measurement constraints. The h {yields} {gamma}{gamma} decay width is decreased by {approx}< 20% in the same mass range. For two or more universal extra dimensions the results are cutoff dependent, and can only be qualitatively ...
2002-04-05
Database of air and noise pollution in Lebanon. Final report
International Nuclear Information System (INIS)
The growing global public concern over deteriorating air quality and greenhouse gases emissions released from various combustion processes, and particularly power plants and transportation system, led governments and local authorities, especially in industrialised countries into taking these issues seriously and establishing standards to reduce air pollution down to acceptable levels, (clean air act, earth summit,...). The transportation sector has another unwanted product, noise pollution caused by different segments of this sector including the noise produced by the engine, tires noise and exhaust noise, in addition to the noise product by private standby generals operating during electricity cut-off periods. To be able to estimate the environmental impacts of the national power plants and the transportation sector, it is necessary to collect enough data (samples of lead emissions, SO_2 concentration, sulfur dioxide, nitrogen oxides, hydrocarbons, ozone and ...
International Nuclear Information System (INIS)
Single crystals of semi-organic L-histidine hydrobromide have been grown by slow evaporation technique from a mixture of L-histidine and hydrobromic acid in aqueous solution at ambient temperature. From high-resolution X-ray diffraction analysis, the crystalline perfection of the grown crystal has been studied. Single crystal X-ray diffraction analyses, Nuclear Magnetic Resonance spectral analysis, Thermo-Gravimetry (TG), Differential Thermal Analysis (DTA) and hardness test have been employed to characterize the as-grown crystals. The UV cutoff wavelength of the grown crystal is below 300 nm and has a wide transparency window, which is suitable for second harmonic generation of laser in the blue region. Nonlinear optical characteristics have been studied using Q switched Nd:YAG laser (#lambda#=1064 nm). The second harmonic generation conversion efficiency of the grown crystals confirms their suitability for frequency conversion applications.
2010-12-15
Can magnetospheric electron temperature be inferred from whistler dispersion measurements
International Nuclear Information System (INIS)
An approximate expression for whistler-mode group velocity is obtained, taking into account the effects of electron temperature and anisotropy, density and ion effects, effects of oblique propagation and a non-dipolarity of the dayside magnetospheric magnetic field. This expression is applied to the propagation of whistlers between one hemisphere and the other. It is pointed out that at frequencies close to the upper cut-off of whistler spectra, perturbations to whistler group delay times due to temperature effects can be of the same order of magnitude as, or even higher than, the corresponding perturbations due to finite electron density and ion effects. A method of magnetospheric electron temperature diagnostics is proposed and applied to two whistlers recorded at Halley (L = 4.3). It is pointed out that the values of temperature obtained from the analysis of whistler spectra depend on the choice of model of electron density and temperature distribution in the ...
International Nuclear Information System (INIS)
To evaluate the role of positron emission tomography-computed tomography (PET-CT) in staging and determining early treatment response to chemotherapy in children with neuroblastoma (NB) and its correlation with the final outcome. Patients and Methods: Seventeen patients of NB with mean age of 51.5 months (age range 2-132 months; 14 males, 3 females) underwent serial "1"8F-fluorodeoxyglucose (FDG) PET-CT imaging. All 17 patients were for staging before any treatment. Twelve of 17 patients underwent "1"3"1I meta-iodobezylguanidine (MIBG) scan and bone scan. MIBG uptake was seen in the primary lesion in 11/12 patients. MIBG uptake in bones was seen in 3/12 patients. All bone lesions were concordant on MIBG and bone scan. Early response to chemotherapy was evaluated after two cycles using PET-CT. A 30% reduction in longest diameter was taken as cut-off value for response on CT based on the response evaluation criteria in solid tumors criteria. Response on PET-CT was ...
Energy Technology Data Exchange (ETDEWEB)
CT is the most accurate method to detect pulmonary emphysema in vivo. They compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT using a density mask program, at two different cut-off levels (-850,-900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow ...
1997-04-01
International Nuclear Information System (INIS)
CT is the most accurate method to detect pulmonary emphysema in vivo. They compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT using a density mask program, at two different cut-off levels (-850,-900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow ...
1997-01-01
International Nuclear Information System (INIS)
Purpose: Radiotherapy (RT) has been the predominant local treatment for Ewing's sarcoma of bone at the University of Florida. Twice-daily hyperfractionated RT was initiated in 1982 to improve local control and functional outcome. This retrospective review compares the results of once-daily vs. twice-daily RT in patients with primary Ewing's sarcoma of an extremity, with emphasis on functional outcome. Methods and Materials: Between June 1971 and January 1990, 37 patients were treated at the University of Florida for nonmetastatic Ewing's sarcoma of bone with a primary lesion in an extremity. Three patients underwent amputation. Of 34 patients treated with RT, 31 had RT alone and 3 had a combination of RT and local excision. Before 1982, 14 patients received once-daily RT; since 1982, 17 patients have received twice-daily RT. Doses of once-daily RT varied from 47 to 61 Gy at 1.8-2 Gy per fraction. Doses of twice-daily RT varied, depending on the response of the soft-tissue component of ...
1996-07-01
The aim of this study was to evaluate the automated urine test strip analyzer Aution Max AX 4280 which uses strips able to measure 12 urinary parameters. For precision study, we considered glucose, protein, blood, leukocytes, nitrite, and pH and the four first were compared with usual methods: chemical measurement or microscopic examination. Reproducibility of the semi quantitative results was determined as the proportion of results falling into the same concentration range. Within-run reproducibility assessed using urine specimens were between 83% and 96%. Between day on quality controlled materials, it was higher (96%), and leukocytes were shared between two classes 250 and 500 cells/microL. For glucose and proteins, linearity was good and comparison with quantitative methods yielded high correlation. The false negative fraction was low and there was no false positive results. For blood, fraction of false positive was 7.5% for 0.3 mg/L of hemoglobin compared with microscopic analysis ...
Utilizing the right mix of environmental cleanup technologies
International Nuclear Information System (INIS)
The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990's), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required continued and significant ...
2007-09-02
International Nuclear Information System (INIS)
Objective: To evaluate the diagnostic value of 64 multidetector-row CT angiography for internal carotid artery (ICA) stenosis and the application in the follow-up of carotid endarterectomy and percutaneous transluminal stenting. Methods: Forty transient ischemic attack (TIA) patients with interpretable CTA and DSA of the cervical carotid arteries were selected from May 2005 to December 2005. This yielded a total of 80 vessels. The CTA curved planar reformations (CPR) and DSA images referenced to the distal cervical internal carotid were graded by two senior neuroradiologists blindly, according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) guidelines. The paired-t test was used to verify the statistical significant difference between pre-operating and post-operating of carotid endarterectomy or percutaneous transluminal stenting in measuring the vascular diameter and area of cross section using CTA. Results: When the 70% stenosis was used as the ...
2006-09-01
THE STATE OF STAR FORMATION AND THE INTERGALACTIC MEDIUM AT z #approx# 6
International Nuclear Information System (INIS)
In the context of stellar reionization in the standard cold dark matter model, we analyze observations at z #approx# 6 and are able to draw three significant conclusions with respect to star formation and the state of the intergalactic medium (IGM) at z #approx# 6. (1) An initial stellar mass function (IMF) more efficient, by a factor of 10-20, in producing ionizing photons than the standard Salpeter IMF is required at z #approx# 6. This may be achieved by having either (a) a metal-enriched IMF with a lower mass cutoff of #>=#30 M_s_u_n or (b) 2%-4% of stellar mass being Population III massive metal-free stars at z #approx# 6. While there is no compelling physical reason or observational evidence to support (a), (b) could plausibly be fulfilled by continued existence of some pockets of uncontaminated, metal-free gas for star formation. (2) The volume-weighted neutral fraction of the IGM of
2010-12-10
Role of Fusion Energy in a Sustainable Global Energy Strategy
Energy Technology Data Exchange (ETDEWEB)
Fusion energy is one of only a few truly long-term energy options. Since its inception in the 1950s, the vision of the fusion energy research program has been to develop a viable means of harnessing the virtually unlimited energy stored in the nuclei of light atoms--the primary fuel deuterium is present as one part in 6,500 of all hydrogen. This vision grew out of the recognition that the immense power radiated by the sun is fueled by nuclear fusion in its hot core. Such high temperatures are a prerequisite for driving significant fusion reactions. The fascinating fourth state of matter at high temperatures is known as plasma. It is only in this fourth state of matter that the nuclei of two light atoms can fuse, releasing the excess energy that was needed to separately bind each of the original two nuclei. Because the nuclei of atoms carry a net positive electric charge, they repel each other. Hydrogenic nuclei, such as deuterium and tritium, must be heated to approximately 100 million ...
2001-03-07
Quantum dots for lasers, amplifiers and computing
Energy Technology Data Exchange (ETDEWEB)
For InAs-GaAs based quantum dot lasers emitting at 1300 nm, digital modulation showing an open eye pattern up to 12 Gb s{sup -1} at room temperature is demonstrated, at 10 Gb s{sup -1} the bit error rate is below 10{sup -12} at -2 dB m receiver power. Cut-off frequencies up to 20 GHz are realised for lasers emitting at 1.1 {mu}m. Passively mode-locked QD lasers generate optical pulses with repetition frequencies between 5 and 50 GHz, with a minimum Fourier limited pulse length of 3 ps. The uncorrelated jitter is below 1 ps. We use here deeply etched narrow ridge waveguide structures which show excellent performance similar to shallow mesa structures, but a circular far field at a ridge width of 1 {mu}m, improving coupling efficiency into fibres. No beam filamentation of the fundamental mode, low a-factors and strongly reduced sensitivity to optical feedback are observed. QD lasers are thus superior to QW lasers for any system or network. Quantum dot semiconductor ...
2005-07-07
Polymorphisms in fatty acid metabolism-related genes are associated with colorectal cancer risk
DEFF Research Database (Denmark)
Colorectal cancer is the third most common malignant tumor and the fourth-leading cause of cancer death worldwide. The crucial role of fatty acids for a number of important biological processes suggests a more in depth analysis of inter-individual differences in fatty acid metabolizing genes as contributing factor to colon carcinogenesis. We examined the association between genetic variability in 43 fatty acid metabolism-related genes and colorectal risk in 1225 CRC cases and 2032 controls participating in the European Prospective Investigation into Cancer and Nutrition study. 392 single nucleotide polymorphisms were selected using pairwise tagging with an r(2) cutoff of 0.8 and a minor allele frequency of >5%. Conditional logistic regression models were used to estimate odds ratios and corresponding 95% confidence intervals. Haplotype analysis was performed using a generalized linear model framework. On the genotype level, HPGD, PLA2G6, and TRPV3 were ...
2010-01-01
In an earlier paper (Phys. Rev. Lett. 66, 41 (1991)), we calculated both the dielectric constant ({epsilon}{sub {infinity}}) and the nonlinear optical susceptibilities for second-harmonic generation ({chi}{sup (2)}) in the static limit for AlP, AlAs, GaP, and GaAs in the local-density approximation with and without a self-energy correction in the form of a scissors operator,'' including local-field effects. In this paper, we expand our presentation of this calculation. Agreement with experiment to within 15% for the nonlinear susceptibility is demonstrated where experiments are available (GaP and GaAs); the dielectric constants are in no worse than 4% agreement with experiment. The virtual hole'' contributions are reformulated to avoid large numerical cancellations in the case of near degeneracies. The virtual electron'' terms dominate over the virtual hole'' terms by about one order of magnitude. ...
1991-12-15
On the continuous measurement of the cosmic-ray intensity, 2
International Nuclear Information System (INIS)
Since November 1971, the cosmic ray neutron intensity has been measured continuously with 3NM-64 neutron monitor at Fukushima University (140"029'E geographic longitude, 37"045'N geographic latitude, 27.6"0N geomagnetic latitude and 10.55 GV cut-off rigidity). After the neutron monitor had been operated during the period of fourteen months at the ground floor of 3-storied ferro-reinforced concrete building, it was removed to the prefabricated house near the old position of the monitor at January 1973. As a result of the removement of the monitor, the expected values for the counting rate and barometric coefficient of our neutron monitor were obtained, 7.5x10"4 cph and -0.64% mb respectively. The monitor was moved out into a new place, the statistical accuracy of counting rate is altered from 0.44% (hourly counting rate) to 0.36%. It can be considered that there is no effect of concrete building near the monitor, for reason that the zenith angle is opened more than ...
Energy Technology Data Exchange (ETDEWEB)
The particle surface of Li[Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}]O{sub 2} was modified by AlF{sub 3} as a new coating material to improve the electrochemical properties in the high cutoff voltage of 4.5 V. The AlF{sub 3}-coated Li[Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}]O{sub 2} showed no difference in the bulk structure compared with the pristine one and the uniform AlF{sub 3} coating layers whose thickness is of about 10 nm covered Li[Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}]O{sub 2} particles, as confirmed by a transmission electron microscopy. The AlF{sub 3} coating on Li[Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}]O{sub 2} particles improved the overall electrochemical properties such as the cyclability, rate capability and thermal stability compared with those of the pristine Li[Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}]O{sub 2}. Such enhancements were attributed to the presence of the stable AlF{sub 3} layer which acts as the interfacial stabilizer on the surface of Li[Ni{sub 1/3}Co{sub ...
2008-04-01
Immunogenicity, efficacy, safety and effectiveness of pneumococcal conjugate vaccines (1998-2006).
In this paper we present an overview of the literature on efficacy and safety trials of the various pneumococcal conjugate vaccines on the market (PCV7) and in development (PCV9, PCV11 and allegedly PCV10 and PCV13), as well as of observations from post-licensure studies. Seven- (PCV7) and nine-valent PCV (PCV9) are reported to be sufficiently immunogenic after administration of a 3+1 schedule in infants in various RCTs. PncOMPC (PCV7 with a protein of N. meningitidis as a carrier) is less immunogenic, though this may have no repercussions for the protective efficacy against clinical disease. PCV7 is 82-97% efficacious against vaccine serotype (VT) IPD, 90% efficacious against (clinically diagnosed) pneumococcal pneumonia, and, like the 11-valent PCV, 57% efficacious against VT acute otitis media. Naturally, it would be of paramount public health interest if the same levels of efficacy and effectiveness could be achieved with fewer doses. Trials studying 2+1 vaccination schedules for ...
2006-12-04
Energy Technology Data Exchange (ETDEWEB)
The authors describe parts of three third-order depositional sequences and their associated system tracts within seismic-scale outcrops of the Lower-Middle Guadalupian Northwestern shelf-to-Delaware basin transition. These sequences are well exposed along a 20-km dip-oriented transect in the western Guadalupe Mountains, Texas and New Mexico. Systems tracts are defined on the basis of lithofacies distribution, stratal geometry, and bounding (stratal termination) surfaces. These Lower-Middle Guadalupian sequences record (1) carbonate platform retrogradation, basin margin erosion, and sediment starvation followed by platform aggradation and progradation (lower San Andres Formation-Cutoff Formation; transgressive and highstand systems tracts), (2) major basin infill by terrigenous clastics bypassed over the underlying lower San Andres highstand carbonate bank and development of a shelf-margin-restricted carbonate bank and coeval base-of-slope apron (Brushy Canyon ...
1990-05-01
International Nuclear Information System (INIS)
The present communication deals with the synthesis, single crystal growth and characterization of a new nonlinear optical material L-proline strontium chloride monohydrate (L-PSCM). Single crystals have been grown using the slow solvent evaporation technique. Single crystal XRD analysis confirmed that the crystal belongs to the orthorhombic structure with lattice parameter a=6.6966(3) A, b=12.4530(5) A, c=15.2432(5) A and space group P2_12_12_1. Presence of various functional groups in L-PSCM and protonation of the ions were confirmed by Fourier transform infrared spectroscopy (FT-IR) analysis. The melting point of the single crystal was found to be 126 "oC using DSC. Ultraviolet-visible spectral analyses showed that the crystal has low UV cut-off at 226 nm combined with very good transparency of 90% in a wide range. The optical band gap was estimated to be 5.82 eV. Capacitance and dielectric-loss measurements were carried out at different temperatures in the ...
2011-01-01
Field simulation of axisymmetric plasma screw pinches by alternating-direction-implicit methods
Energy Technology Data Exchange (ETDEWEB)
An axisymmetric plasma screw pinch is an axisymmetric column of ionized gaseous plasma radially confined by forces from axial and azimuthal currents driven in the plasma and its surroundings. This dissertation is a contribution to detailed, high resolution computer simulation of dynamic plasma screw pinches in 2-d {ital rz}-coordinates. The simulation algorithm combines electron fluid and particle-in-cell (PIC) ion models to represent the plasma in a hybrid fashion. The plasma is assumed to be quasineutral; along with the Darwin approximation to the Maxwell equations, this implies application of Ampere`s law without displacement current. Electron inertia is assumed negligible so that advective terms in the electron momentum equation are ignored. Electrons and ions have separate scalar temperatures, and a scalar plasma electrical resistivity is assumed. Altemating-direction-implicit (ADI) methods are used to advance the electron fluid drift velocity and the magnetic fields in the ...
1996-06-01
Experience with pressuriser for PHT pressure control in TAPP 4 reactor
International Nuclear Information System (INIS)
In a 540 MWe PHWR reactor at TAPP-4 the pressuriser has been incorporated in the PHT pressure control system to provide the necessary vapour cushion for PHT main circuit to reduce pressure variations due to transients involving swell and shrinkage. Need for the Pressuriser is due to the large inventory in PHT main circuit and relatively large heat source. The incorporation of Pressuriser is one of the modifications while upgrading from prevalent operating 220 MWe reactors to the present 540 MWe at TAPP-4. The sizing, design and selection of the 540 MWe Pressuriser has been done w.r.t swell/shrinkage requirement during normal/transient operation of the reactor. In this paper the commissioning and operating experience of the Pressuriser in conjunction with the PHT pressure control system is presented. During light water commissioning of PHT circuit some major hurdles like failure of pressuriser heaters due to faulty instrumentation were faced. Subsequently the following corrective action ...
2006-11-13
Edge biasing in the WEGA stellarator
Energy Technology Data Exchange (ETDEWEB)
The WEGA stellarator is used to confine low temperature, overdense (densities exceeding the cut-off density of the heating wave) plasmas by magnetic fields in the range of B=50-500 mT. Microwave heating systems are used to ignite gas discharges using hydrogen, helium, neon or argon as working gases. The produced plasmas have been analyzed using Langmuir and emissive probes, a single-channel interferometer and ultra-high resolution Doppler spectroscopy. For a typical argon discharge in the low field operation, B=56 mT, the maximum electron density is n{sub e}{proportional_to}10{sup 18} m{sup -3} with temperatures in the range of T=4-12 eV. The plasma parameters are determined by using Langmuir probes and are cross-checked with interferometry. It is demonstrated within this work that the joint use of emissive probes and ultra-high resolution Doppler spectroscopy allows a precise measurement of the radial electric field. The focus of this work is on demonstrating the ...
2009-02-27
Study on dose distribution of therapeutic proton beams with prompt gamma measurement
Energy Technology Data Exchange (ETDEWEB)
The proton beam has an advantage of the sharp dose falloff in dose distribution called Bragg peak while conventional radiation therapy modalities such as photons exhibit considerable amount of exit dose. To take advantage of this property it is important to know the exact location of the distal dose falloff. An error can cause overdose to the normal tissue or underdose to the tumor volume. The only way of finding out the dose distribution in-situ in particle therapy is to measure the gammas produced by nuclear reactions with tissue materials. Two kinds of gammas can be used: one is prompt gamma and the other is coincident gamma from the positron-emission isotopes. We chose to detect prompt gammas, and developed a prompt gamma scanning system (PGS). The proton beams of the proton therapy facility at National Cancer Center were used. The gamma distribution was compared to the dose distribution measured by an ionization chamber at three different energies of 100, 150, 200 MeV's. ...
2007-03-15
Energy Technology Data Exchange (ETDEWEB)
Leakage of CO{sub 2} and displaced brine from geologic carbon sequestration (GCS) sites into potable groundwater or to the near-surface environment is a primary concern for safety and effectiveness of GCS. The focus of this study is on the estimation of the probability of CO{sub 2} leakage along conduits such as faults and fractures. This probability is controlled by (1) the probability that the CO{sub 2} plume encounters a conductive fault that could serve as a conduit for CO{sub 2} to leak through the sealing formation, and (2) the probability that the conductive fault(s) intersected by the CO{sub 2} plume are connected to other conductive faults in such a way that a connected flow path is formed to allow CO{sub 2} to leak to environmental resources that may be impacted by leakage. This work is designed to fit into the certification framework for geological CO{sub 2} storage, which represents vulnerable resources such as potable groundwater, health and safety, and the near-surface ...
2009-05-01
International Nuclear Information System (INIS)
Objective: To investigate the predictive value of ADC value in grading of neuroepithelial tumors. Methods: The clinical data and images of 70 patients with neuroepithelial tumors pathologically proven were collected and analyzed retrospectively. All the patients were classified into low (WHO I or II) and high (WHO III or IV) grade groups which included 40 and 30 cases respectively according to the 2007 WHO classification of tumours of the central nervous system. All the patients underwent plain and contrast-enhanced MR scan and DWI before surgery. The minimum ADC (MinADC) value was measured postoperatively on ADC maps. The Ki-67 labeling index (Ki-67 LI) of tumor tissue was determined by immunohistochemistry. MinADC values for two groups were analyzed using student t test, while the age and Ki-67 LI for the two groups was analyzed using Mann-Whitney test (P<0.05 considered to be significant). Also the MinADC value and Ki-67 LI were analyzed with Pearson correlation. The receiver ...
2009-11-01
Atomic interactions between plutonium and helium.
Energy Technology Data Exchange (ETDEWEB)
An essential issue in gallium (Ga)-stabilized fcc-phase plutonium ({delta}-Pu) is the formation of helium (He) voids and bubbles emanating from the radiolytic decay of the Pu. The rate of formation of He voids and bubbles is related to the He-defect formation energies and their associated migration barriers. The size and shape distributions of the bubbles are coupled to these critical migration processes. The values of the defect formation energies, internal pressure, and migration barriers can be estimated from atomistic calculations. Complicating this picture is the destruction of He-filled voids and bubbles by subsequent radiolytic decay events. The present study concerns the construction of the necessary potential energy surfaces for the Pu-He and He-He interactions within the modified embedded atom method (MEAM). Once fully tested, the potentials will be used to estimate the He-defect formation energies and barriers to the migration of these defects for both interstitial and ...
2002-01-01
40th Anniversary of the First Proton-Proton Collisions in the CERN Intersecting Storage Rings (ISR)
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