WorldWideScience
1

Phantom and animal imaging studies using PLS synchrotron X-rays  

CERN Document Server

Ultra-high resolution radiographs can be obtained using synchrotron X-rays. A collaboration team consisting of K-JIST, POSTECH and YUMC has recently commissioned a new beamline (5C1) at Pohang Light Source (PLS) in Korea for medical applications using phase contrast radiology. Relatively simple image acquisition systems were set up on 5C1 beamline, and imaging studies were performed for resolution test patterns, mammographic phantom, and animals. Resolution test patterns and mammographic phantom images showed much better image resolution and quality with the 5C1 imaging system than the mammography system. Both fish and mouse images with 5C1 imaging system also showed much better image resolution with great details of organs and anatomy compared to those obtained with a conventional mammography system. A simple and inexpensive ultra-high ...

2001-01-01

2

Ultra High Strength Beta Titanium Alloy for Fasteners.  

Science.gov (United States)

... Accession Number : ADD151811. Title : Ultra High Strength Beta Titanium Alloy for Fasteners. Descriptive Note : Journal article,. ...

7

Mesodynamics in the SARS nucleocapsid measured by NMR field cycling  

Energy Technology Data Exchange (ETDEWEB)

Protein motions on all timescales faster than molecular tumbling are encoded in the spectral density. The dissection of complex protein dynamics is typically performed using relaxation rates determined at high and ultra-high field. Here we expand this range of the spectral density to low fields through field cycling using the nucleocapsid protein of the SARS coronavirus as a model system. The field-cycling approach enables site-specific measurements of R{sub 1} at low fields with the sensitivity and resolution of a high-field magnet. These data, together with high-field relaxation and heteronuclear NOE, provide evidence for correlated rigid-body motions of the entire {beta}-hairpin, and corresponding motions of adjacent loops with a time constant of 0.8 ns (mesodynamics). MD simulations substantiate these findings and provide direct verification of the time scale and collective ...

2009-09-15

8

High Angular Resolution Imaging Spectroscopy of the Galactic Ultra-Compact HII Region K3-50A  

CERN Document Server

Gemini North adaptive optics imaging spectroscopy is presented for the Galactic ultra-compact HII (UCHII) region K3-50A. Data were obtained in the K-band using the Near-infrared Integral Field Spectrograph (NIFS) behind the facility adaptive optics module ALTAIR in natural guide star mode. The NIFS data cube reveals a complex spatial morphology across the 0.1 pc scale of the 3'' UCHII region. Comparison of the nebular emission to Cloudy ionization models shows that the central source must have an effective temperature between about 37000 K and 45000 K with preferred values near 40000 K. Evidence is presented for sharp density variations in the nebula which are interpreted as a clearing of material nearest the central source. High excitation lines of FeIII and SeIV show that the ionization of the nebula clearly changes with distance from the central source. A double lobed kinematic signature (+/- 25 kms) is evident in the Br gamma line map which ...

2009-01-01

9

COSY synchrotron and storage ring for medium energy physics  

Energy Technology Data Exchange (ETDEWEB)

At present the cooler synchrotron COSY a synchrotron and storage ring for medium energy physics is being commissioned at Juelich. The construction of the ring was finished during September 1992. The cooler ring will deliver protons in the momentum range from 270 to 3300 MeV/c. The phase density of the circulating protons will be increased with electron cooling at injection and with stochastic cooling at momenta between 1500 and 3300 MeV/c. High luminosity internal experiments as well as high resolution external experiments will be possible. Details of the lattice, to match the different ion optical requirements for cooling, acceleration, internal experiments and ultra-slow extraction will be discussed. An overview of the performance of the ion sources, the injector cyclotron, the ring, the injection beamline are given. The realization status of the extraction beamlines to the external experimental area ...

1993-01-01

12

Non-destructive Imaging of Individual Bio-Molecules  

CERN Document Server

Radiation damage is considered to be the major problem that still prevents imaging an individual biological molecule for structural analysis. So far, all known mapping techniques using sufficient short wave-length radiation, be it X-rays or high energy electrons, circumvent this problem by averaging over many molecules. Averaging, however, leaves conformational details uncovered. Even the anticipated use of ultra-short but extremely bright X-ray bursts of a Free Electron Laser shall afford averaging over 10^6 molecules to arrive at atomic resolution. Here we present direct experimental evidence for non-destructive imaging of individual DNA molecules. In fact, we show that DNA withstands coherent low energy electron radiation with deBroglie wavelength in the Angstrom regime despite a vast dose of 10^8 electrons/nm^2 accumulated over more than one hour.

2009-01-01

13

Land Cover Classification Comparison with Different Resolution ...  

Science.gov (United States)

Dec 9, 2005 ... Classification of high resolution imagery is not as straightforward as more ... The challenges of classifying high resolution imagery stems ...

14

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 ...

2009-02-27

15

Acidic and neutral polar NSO compounds in Smackover oils of different thermal maturity revealed by electrospray high field Fourier transform ion cyclotron resonance mass spectrometry  

Energy Technology Data Exchange (ETDEWEB)

Negative ion electrospray ionization (ESI) coupled with high field Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) allows for the direct detection of acidic NSO compounds in petroleum. The technique requires no chromatographic separation, is able to distinguish 18 different compound classes (e.g., neutral nitrogen, carboxylic acids and oxygenates), and can identify {approx}14,000 distinct masses by ultra-high mass resolution and mass accuracy. We previously studied three crude oils from different geological origins [Organic Geochemistry 33 (2002b) 743-759]. Here, we expand our research by comparing two source-equivalent Smackover oils of different levels of thermal maturity. We observe clear differences in the distribution of NSO compound classes, types (number of rings plus double bonds within a class), and number of alkyl carbons. With increasing thermal stress, the relative amount of sulfur and ...

2004-07-01

16

Research and development project in fiscal 1989 for fundamental technologies for next generation industries. Achievement report on research and development on photoreactive materials (Research on function separating type photochromic materials); 1989 nendo hikari hanno zairyo no kenkyu kaihatsu seika hokokusho. Kino bunrigata photochromic zairyo ni kansuru kenkyu  

Energy Technology Data Exchange (ETDEWEB)

Research and development has been performed on photochromic materials expected to be used in ultra-high density recording, high resolution indication and photoswitches. With regard to molecular orientation in the ternary system mixed LB film, the result of structural analysis by XPM spectrum revealed that the acceptor constituent in the LB film is so structured that it is separated and laminated with two other constituents, and that the sensitizer constituent and the donor constituent are not recognized of being separated definitely. Regarding the electron movement reaction in the solid phase system, a photo-current measuring experiment was carried out on the laminated film which is vacuum-deposited with the ternary system comprising of the donor, sensitizer, and acceptor. It was concluded that the observed photo-current reflects the electron movement reaction in the solid phase as it is. For the photo-current in the LB ...

1990-03-01

17

Energy-filtered electron microscopy for imaging core-shell nanostructures  

Energy Technology Data Exchange (ETDEWEB)

CuAg core-shell nanoparticles are synthesized by ultra-high vacuum thermal evaporation. We show on this system how the Energy-Filtered Transmission Electron Microscopy (EFTEM) technique allows one to improve the characterization by precisely pointing out the formation of core-shell arrangements in bimetallic nanoparticle assemblies. A criterion to measure the shell thickness from EFTEM images on unique core-shell nanoparticles is defined, that can be used for core-shell nanoparticles of any sizes, with shell thicknesses over 1 nm. It is based on the intensity variation along a line drawn across a core-shell nanoparticle on a EFTEM image. This criterion has been validated by a close comparison of the shell thickness measurements performed in this work and the ones obtained by acoustic micro-Raman spectroscopy. Using this criterion, we report a strong correlation between the size of the Cu cores and the formation of the core-shell arrangements in the nanoparticle ...

2008-08-15

18

Study of silicon damage caused by ultra-low energy boron implantation  

International Nuclear Information System (INIS)

Ultra-shallow junction formation in deep submicron Si devices is limited by anomalous diffusion of the dopant, which is related to the release of interstitials from defect clusters formed during the implantation of energetic ions or the subsequent annealing. The work described in this dissertation is concerned with the effects of low energy B ion implantation, especially damage formation, clustering and its annealing. After a review of the stopping and ranges of energetic ions in Si, the formation of implant damage, in particular of point defects, their migration, agglomeration and annihilation, including the involvement of dopant ions, is considered. A description of the Salford ultra low energy implanter is given and the main analysis technique, medium ion energy scattering (MEIS) reviewed. Additional analytical techniques used, such as secondary ion mass spectrometry (SIMS), 4-point probe and cross section transmission microscopy (XTEM) as ...

19

Report of the Geostatistical Analysis of High Resolution ...  

Science.gov (United States)

... The variogram analysis of the high resolution imagery has shown that although more spatial scales have been identified than from the SPOT image ...

1998-05-01

20

PV Conversion Technologies, Session: OPV, Sensitized, Seed (Presentation)  

Energy Technology Data Exchange (ETDEWEB)

The NREL Sensitized Solar Cell (SSC) Core Program supports the Solar America Initiative by: (1) targeting new devices and processes for commercialization by 2015 that are less expensive, more efficient, highly reliable, and environmentally benign; (2) collaborating with DOE OS/BES to conduct basic research targeting breakthroughs in key areas, such as ultra-high efficiency and/or ultra-low cost materials and devices.

2008-04-01

21

Radiations emitted in the decay of /sup 165/Er: A promising medical radionuclide  

Science.gov (United States)

The 10.3-h /sup 165/Er, decaying by electron capture to stable /sup 165/Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in /sup 165/Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of /sup 169/Er and /sup 171/Er radioactive impurities in the reactor-produced /sup 165/Er sample are experimentally determined. Whole-body dose estimates for /sup 165/Er are given. These compare favorably with /sup 99/Tc dose.

1977-05-01

22

Radiations emitted in the decay of "1"6"5Er: A promising medical radionuclide  

International Nuclear Information System (INIS)

The 10.3-h "1"6"5Er, decaying by electron capture to stable "1"6"5Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in "1"6"5Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of "1"6"9Er and "1"7"1Er radioactive impurities in the reactor-produced "1"6"5Er sample are experimentally determined. Whole-body dose estimates for "1"6"5Er are given. These compare favorably with "9"9Tc dose.

23

Laser stabilization at 1536 nm using regenerative spectral hole burning  

International Nuclear Information System (INIS)

Laser frequency stabilization giving a 500-Hz Allan deviation for a 2-ms integration time with drift reduced to 7 kHz/min over several minutes was achieved at 1536 nm in the optical communication band. A continuously regenerated spectral hole in the inhomogeneously broadened "4I_1_5_/_2(1)#->#"4I_1_3_/_2(1) optical absorption of an Er"3"+:Y_2SiO_5 crystal was used as the short-term frequency reference, while a variation on the locking technique allowed simultaneous use of the inhomogeneously broadened absorption line as a long-term reference. The reported frequency stability was achieved without vibration isolation. Spectral hole burning frequency stabilization provides ideal laser sources for high-resolution spectroscopy, real-time optical signal processing, and a range of applications requiring ultra-narrow-band light sources or coherent detection; the time scale for stability and the compatibility with spectral hole burning devices make ...

2001-04-15

30

Ultra high field magnetic resonance imaging  

International Nuclear Information System (INIS)

Understanding human brain function, brain development and brain dysfunction is one of the great challenges of the twenty first century. Biomedical imaging has now run up against a number of technical constraints that are exposing limits to its potential. In order to overcome the current limits to high-field magnetic resonance cerebral imaging (MRI) and unleash its fullest potential, the Cea has built NeuroSpin, an ultra-high-field neuroimaging facility at its Saclay centre (in the Essonne). NeuroSpin already boasts three fully operational MRI systems. The first is a 3-tesla high-field system and the second is a very-high-field 7-tesla system, both of which are dedicated to clinical studies and investigations in humans, while the third is an ultra-high-field 17.65-tesla system designed for studies on small animals. In 2011, NeuroSpin will be commissioning an 11.7-tesla ...

31

Free-electron laser driven by the LBNL laser-plasma accelerator  

Energy Technology Data Exchange (ETDEWEB)

A design of a compact free-electron laser (FEL), generating ultra-fast, high-peak flux, XUV pulses is presented. The FEL is driven by ahigh-current, 0.5 GeV electron beam from the Lawrence Berkeley National Laboratory (LBNL) laser-plasma accelerator, whose active acceleration length is only a few centimeters. The proposed ultra-fast source (~;;10 fs) would be intrinsically temporally synchronized to the drive laser pulse, enabling pump-probe studies in ultra-fast science. Owing to the high current (>10 kA) of the laser-plasma-accelerated electron beams, saturated output fluxes are potentially greater than 10^13 photons/pulse. Devices based both on self-amplified spontaneous emission and high-harmonic generated input seeds, to reduce undulator length and fluctuations, are considered.

2008-08-04

32

Railgun. Challenge to ultra-high speed; Railgun. Chokosoku eno chosen  

Energy Technology Data Exchange (ETDEWEB)

A railgun has an armature driven between two rail-like conductors. In other words, it is a linear drive device system that drives airframes by using the Lorentz`s force. The system is expected as a next-generation high-speed transport means, or as a means to create such ultimate fields as ultra-high pressures, ultra-high temperatures, and ultra-ferromagnetic fields. This paper is a report on investigations on the relevant technological trends as surveyed by the investigation committee at the Institute of Electrical Engineers of Japan using research reports published inside and outside the country. The reported themes cover explanations from the construction to the pulse power supply that forms the core of the technology, problems in switching, recent status of research and development, and to application fields. Compatibility in the high-level electrical and mechanical performances ...

1995-09-12

33

Design and fabrication of large ultra-thin PIN detector with membrane stress deviation  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the design of large thin PIN detector with a membrane stress avoidance configuration is proposed, and the related device fabrication process is developed. Ultra-thin PIN detector {approx} 1.13 cm{sup 2} in area is fabricated on a thin ( {approx} 35{mu}m) silicon membrane, and characterized. Detector performance improvement has been successfully demonstrated. With the membrane stress avoidance design, the improved detector exhibits a leakage of 6nA, which is at least 5 times lower than that of detector of identical junction area. The new detector features a full depleted capacitance of 110 pF, and a FWHM of 40.86 keV energy resolution for 5.486 MeV alpha particle spectrography.

2010-09-15

34

System Design and Applications of the Ultra Small ... - GLTRS - NASA  

Science.gov (United States)

The advanced technologies of Ka-Band systems such as high gain spot .... sometimes used based on link requirements for a specific application. .... received at NASA LeRC from a Ku-band satellite and retransmitted to the USAT at Ka-Band. .... and to the Office of Management and Budget, Paperwork Reduction Project ...

35

High speed optical coherence microscopy with autofocus adjustment and a miniaturized endoscopic imaging probe  

UK PubMed Central (United Kingdom)

Optical coherence microscopy (OCM) is a promising technique or high resolution cellular imaging in human tissues. An OCM system for high-speed en face cellular resolution imaging...Full Text Available

2010-03-01

36

Corrosion resistance of Ultra-Low-Carbon 19% Cr-11% Ni stainless steel for nuclear fuel reprocessing plants in nitric acid  

International Nuclear Information System (INIS)

An Ultra-Low-Carbon 19% Cr-11% Ni Stainless Steels used in nuclear fuel reprocessing plants where highly corrosion resistance in nitric acid is required has been developed. This steel has optimized the chemistry composition to decrease inclusions and deformation-induced martensitic transformation. The formation of deformation-induced martensite has the potential danger of accelerating corrosion in nitric acid. In this paper, effects of cold reduction and martensitic transformation on corrosion resistance of Ultra-Low-Carbon Stainless Steels in nitric acid are discussed. The developed steel showed excellent corrosion resistance during long-term exposure to nitric acid. (author).

37

A new application of MRT of the lung using ultra-shot turbo spin echo sequences (UTSE)  

International Nuclear Information System (INIS)

T_2 weighted ultra-short turbo spin echo sequences were used in five individuals with variations in echo times, delayed triggering and echo intervals. To reduce movement artifacts all examinations were carried out with ECG and respiratory triggering. The sequences giving optimal image quality were then employed in 19 patients having various pulmonary abnormalities. Image resolutions, artifacts, image contrasts and diagnostic value were then judged by two observers and compared with CT. In the first study, a diastole-triggered UTSE sequence with the shortest echo proved optimal (T_E=90 ms, T_R=2-4 s, echo=9 ms, turbo factor=19). In the patient series studied, MRT was inferior to CT with regard to resolution and number of artifacts, but better in respect of contrast and diagnostic value. Using UTSE of the lung, MRT can produce images of good quality. Compared with CT, contrast is better with MRT, offering diagnostic ...

38

"Mtrack 2.0": An ultra-scale tracking algorithm for low-resolution overhead imagery  

Energy Technology Data Exchange (ETDEWEB)

Overhead persistent surveillance systems are becoming more capable at acquiring wide-field image sequences for long time-spans. The need to exploit this data is becoming ever greater. The ability to track a single vehicle of interest or to track all the observable vehicles, which may number in the thousands, over large, cluttered regions while they persist in the imagery is very desirable. Typically, this imagery has many thousands of pixels on a side and is characterized by lower resolutions (e.g. {approx}0.5 meters/pixel to {approx}2.0 meters/pixel) and lower frame rates (e.g. {approx} sub-Hz to several Hz). We describe our ultra-scale capable implementation of a multiple-vehicle tracking algorithm for overhead persistent surveillance imagery. This work builds upon an earlier report, where now the algorithm has been modified for improved performance and has been substantially improved to handle much larger datasets in a much shorter time.

2008-09-26

39

Visual mental imagery during caloric vestibular stimulation  

UK PubMed Central (United Kingdom)

We investigated high-resolution mental imagery and mental rotation, while the participants received caloric vestibular stimulation. High-resolution visual mental imagery tasks have been shown...Full Text Available

2006-01-01

40

High-resolution infrared observations in IC 5146  

Energy Technology Data Exchange (ETDEWEB)

High-resolution near-infrared and far-infrared observations are presented of the southeastern molecular cloud fragment in the IC 5146 dark cloud. These observations rule out earlier suggestions for the formation of massive stars in this fragment.

1984-04-01

41

High-Speed Ultrahigh-Resolution Optical Coherence Tomography Findings in Chronic Solar Retinopathy  

UK PubMed Central (United Kingdom)

PurposeTo describe ocular findings for a 34-year-old man with chronic solar retinopathy using high-speed ultrahigh-resolution (UHR) optical coherence tomography (OCT).Full Text Available

2008-01-01

43

Nuclear structure physics at high resolution  

Energy Technology Data Exchange (ETDEWEB)

Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)

1985-04-01

44

High Resolution Mesoscale Weather Data Improvement to ...  

Science.gov (United States)

... that defines hydrometeor categories for the duration of the simulation ... and to observe the movement of any particular system ... particle settling occurred ...

2007-03-01

45

C-CAP Land Cover, Maui, Hawaii 2006  

Science.gov (United States)

This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change ... ...

46

Ultra-high pressure water jet: Baseline report  

International Nuclear Information System (INIS)

The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU's evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky trademark pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is ...

1997-07-01

47

High resolution sequence stratigraphy in China  

International Nuclear Information System (INIS)

Since high resolution sequence stratigraphy was introduced into China by DENG Hong-wen in 1995, it has been experienced two development stages in China which are the beginning stage of theory research and development of theory research and application, and the stage of theoretical maturity and widely application that is going into. It is proved by practices that high resolution sequence stratigraphy plays more and more important roles in the exploration and development of oil and gas in Chinese continental oil-bearing basin and the research field spreads to the exploration of coal mine, uranium mine and other strata deposits. However, the theory of high resolution sequence stratigraphy still has some shortages, it should be improved in many aspects. The authors point out that high resolution sequence stratigraphy should ...

2008-11-01

48

Ultra-thin {sup 242m}Am fuel elements in nuclear reactors  

Energy Technology Data Exchange (ETDEWEB)

There is a growing interest in using {sup 242m}Am as a nuclear fuel. The advantages of {sup 242m}Am as a nuclear fuel derive from the fact that {sup 242m}Am has the highest thermal fission cross section. The thermal capture cross section is relatively low and the number of neutrons per thermal fission is high. These nuclear properties make it possible to obtain nuclear criticality with ultra-thin fuel elements. The possibility of having ultra-thin fuel elements enables the use of these fission products directly, without the necessity of converting their energy to heat, as is done in conventional reactors. There are three options of using such highly energetic and highly ionized fission products. - Using the fission products themselves for ionic propulsion. - Using the fission products in an MHD generator, in order to obtain electricity directly. - Using the fission products to heat ...

2000-12-01

49

Tailor die quenching in hot stamping for producing ultra-high strength steel formed parts having strength distribution  

British Library Electronic Table of Contents (United Kingdom)

Tailor die quenching in the hot stamping of quenchable steel sheets was developed to produce ultra-high strength steel formed parts having strength distribution. Local portions of the heated sheet were quenched by holding grooved tools at the bottom dead centre during the stamping. Non-contact portions were generated in the sheet by grooving the tools, and thus the strength in the contact portions is high owing to the quenching and that in the non-contact portions is low owing to the lack of the quenching. Hat-shaped products having a tensile strength of approximately 1.5GPa only at four corners were formed.

2010-01-01

50

Production and characterization of ultrafine WC powders  

International Nuclear Information System (INIS)

The conventional Calzination-Reduction-Carburization (CRC) process offers the potential to manufacture commercial WC powders with median SEM grain sizes below 0.5 pm (ultra fine grades). Strict process control and a high degree of automation have led to increased powder uniformity and high lot-to-lot reliability. The high potential and flexibility of the CRC process is shown by the development of tailor made WC powders with regard to subsequent alloy manufacturing. R and D powders have successfully been processed in full-scale units exhibiting SEM grain sizes of 0.15 - 0.20 pm. This paper discusses the powder characteristics of various ultra fine WC powder grades, stemming from the conventional CRC process. Analytical characterization include also field-emission SEM, bright field TEM, EDX analysis and XRD-line broadening. (author)

2001-05-01

51

Mechanical properties and structure of low-alloy ultra-high strength steels  

Energy Technology Data Exchange (ETDEWEB)

Mechanical properties of P-LDHA and V-ROL N steels of the Czech production are compared with other ultra-high strength steels produced in the world. The most important results can be summarized into following points: 1. Optimally heat treated P-LDHA steel exhibits substantially better strength characteristics then the V-ROL N steel. 2. Optimal tempering temperature of the P-LDHA steel is 300 C. 3. Basic mechanical properties of P-LDHA steel belong to the top of the UHS steels ranking and are well comparable with those of American 300 M steel. 4. In the low-cycle fatigue region, the P-LDHA steel exhibits slightly better fatigue resistance then the 300 M steel. On the other hand, the high-cycle fatigue resistance of 300 M steel is slightly better then that of the P-LDHA steel. (orig.)

2000-07-01

52

Development of Ultra-Fast Silicon Switches for Active X-Band High Power RF Compression Systems  

Energy Technology Data Exchange (ETDEWEB)

We present the recent results of our research on the high power ultra-fast silicon RF switches. This switch is composed of a group of PIN diodes on a high purity silicon wafer. The wafer is inserted into a cylindrical waveguide under TE{sub 01} mode, performing switching by injecting carriers into the bulk silicon. Our current design uses a CMOS compatible process and the device was fabricated at SNF (Stanford Nanofabrication Facility). 300 ns switching time has been observed, while the switching speed can be improved further with 3-D device structure and faster driving circuit. Power handling capacity of the switch is at the level of 10 MW. The switch was designed for active X-band RF pulse compression systems--especially for NLC, but it is also possible to be modified for other applications and other frequencies.

2006-03-06

53

Nuclear magnetic resonance imaging of hepatic focal injuries with phased array antennae surface: apnoea or high resolution imagery?  

International Nuclear Information System (INIS)

French English ... Orig. Title Imagerie IRM des lesions focales hepatiques avec les antennes de surface en reseau phase (phased array): apnee ou imagerie haute resolution?.

1995-10-26

54

Investigation of the hadronic final state in electron-proton interactions at HERA  

Energy Technology Data Exchange (ETDEWEB)

The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10{sup -15} cm. (orig./HSI).

1995-09-18

55

Comparison of Detector Intrinsic Spatial Resolution Characteristics for Sensor on the Entrance Surface and Conventional Readout Designs  

UK PubMed Central (United Kingdom)

We report on a high resolution, monolithic crystal PET detector design concept that provides depth of interaction (DOI) positioning within the crystal. Our design utilizes a novel sensor on...Full Text Available

2010-01-01

56

Improvement of spatial resolution in the longitudinal direction for isotropic imaging in helical CT  

Energy Technology Data Exchange (ETDEWEB)

Experiments were conducted to confirm the isotropic spatial resolution of multislice CT with a 0.5 mm slice thickness. Isotropic spatial resolution means that the spatial resolution in the transaxial plane (X-Y plane) and that in the longitudinal direction (Z direction) are equivalent. To obtain point spread function (PSF) values in the X-Y-Z directions, three-dimensional voxel data were obtained by helical scanning of a bead phantom. The modulation transfer function (MTF) values were then obtained by three-dimensional Fourier transform of the PSF. Evaluation of the spatial resolution in the X-Y-Z directions by the MTF values showed that the spatial resolution in the Z direction does not depend on the reconstruction kernel used. It was also found that the spatial resolution in the Z direction, as compared with that in the X-Y plane, is superior with the standard ...

2007-02-07

57

Steel microstructure engineering for large diameter tubes; Engenharia de microestrutura de acos para tubos de grande diametro  

Energy Technology Data Exchange (ETDEWEB)

High and ultra-high strength steels for pipelines are produced by properly handling the steel microstructure. The metallurgical principles involved in the microstructure control are presented, with emphasis on TMCP processing, that comprises conventional controlled rolling followed by accelerated cooling. (author)

2008-05-15

58

New designs for Ultra High High-Power Single Transverse Mode Cw fibre lasers  

International Nuclear Information System (INIS)

Overcoming the limiting constraints of stimulated Raman scattering (SRS) and stimulated Brilluoin scattering (SBS) poses serious fibre design challenges for increasing the output power of optical amplifiers and lasers. New fibre amplifier designs are proposed to break out of these limitations to reach several kWs CW powers. (Author)

2009-04-01

59

Separation of rubidium from irradiated aluminum-encapsulated uranium  

International Nuclear Information System (INIS)

A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.

1993-05-01

60

Separation of rubidium from irradiated aluminum-encapsulated uranium  

Energy Technology Data Exchange (ETDEWEB)

A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.

1982-01-01

61

Hydrogen transport and embrittlement in 300 M and AerMet100 ultra high strength steels  

Energy Technology Data Exchange (ETDEWEB)

This paper describes how hydrogen transport affects the severity of hydrogen embrittlement in 300 M and AerMet100 ultra high strength steels. Slow strain rate tests were carried out on specimens coated with electrodeposited cadmium and aluminium-based SermeTel 1140/962. Hydrogen diffusivities were measured using two-cell permeation and galvanostatic charging methods and values of 8.0 x 10{sup -8} and 1.0 x 10{sup -9} cm{sup 2} s{sup -1} were obtained for 300 M and AerMet100, respectively. A two-dimensional diffusion model was used to predict the hydrogen distributions in the SSR specimens at the time of failure. The superior embrittlement resistance of AerMet100 was attributed to reverted austenite forming around martensite laths during tempering.

2010-05-15

62

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V{sub GS} = V{sub DS}/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted ...

2005-01-01

63

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

International Nuclear Information System (INIS)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V_G_S = V_D_S/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted in ...

2005-01-01

66

Study on high-resolution sequence stratigraphy framework of uranium-hosting rock series in Qianjiadian sag  

International Nuclear Information System (INIS)

The ore-hosting Yaojia Formation is composed of a set of braided stream medium-fine grained sediments. Guided by the basic theory of high-resolution sequence stratigraphy, and based on the core observation, the analysis of chemical composition of rocks, and data of natural potential logging and apparent resistivity logging, the authors have set up the high-resolution sequence stratigraphy framework of the ore-hosting Yaojia Formation, and discussed the relation of the stratigraphic structure of the middle cycle, as well as the paleotopography, the micro-facies to the formation of uranium deposit. (authors)

2005-07-01

67

RAPID DAMAGE ASSESSMENT FROM HIGH RESOLUTION IMAGERY  

Energy Technology Data Exchange (ETDEWEB)

Disaster impact modeling and analysis uses huge volumes of image data that are produced immediately following a natural or an anthropogenic disaster event. Rapid damage assessment is the key to time critical decision support in disaster management to better utilize available response resources and accelerate recovery and relief efforts. But exploiting huge volumes of high resolution image data for identifying damaged areas with robust consistency in near real time is a challenging task. In this paper, we present an automated image analysis technique to identify areas of structural damage from high resolution optical satellite data using features based on image content.

2008-07-01

68

Development of high resolution imaging detectors for X-ray astronomy  

Energy Technology Data Exchange (ETDEWEB)

High (spatial) resolution imaging detectors for X-ray astronomy were developed. Several prototype detectors built and their feasibility and baseline performance were assessed. Two of these detector types are proposed for investigations on the advanced X-ray astrophysics facility (AXAF). The readiness of a new X-ray imaging system, the charge coupled device (CCD) imaging specctrometer is outlined, and state of the art performance parameters for microchannel plate (MCP) and CCD detectors are measured. Laboratory facilities and procedures for coating MCP are developed general high resolution imagery systems are analyzed.

1985-03-01

69

Development of high resolution imaging detectors for X-ray astronomy  

International Nuclear Information System (INIS)

High (spatial) resolution imaging detectors for X-ray astronomy were developed. Several prototype detectors built and their feasibility and baseline performance were assessed. Two of these detector types are proposed for investigations on the advanced X-ray astrophysics facility (AXAF). The readiness of a new X-ray imaging system, the charge coupled device (CCD) imaging specctrometer is outlined, and state of the art performance parameters for microchannel plate (MCP) and CCD detectors are measured. Laboratory facilities and procedures for coating MCP are developed general high resolution imagery systems are analyzed.

1985-01-01

70

Aerogels from Unaltered Bacterial Cellulose: Application of scCO2 Drying for the Preparation of Shaped, Ultra-Lightweight Cellulosic Aerogels  

British Library Electronic Table of Contents (United Kingdom)

Bacterial cellulose produced by the gram-negative bacterium Gluconacetobacter xylinum was found to be an excellent native starting material for preparing shaped ultra-lightweight cellulose aerogels. The procedure comprises thorough washing and sterilization of the aquogel, quantitative solvent exchange and subsequent drying with supercritical carbon dioxide at 40 degreeC and 100 bar. The average density of the obtained dry cellulose aerogels is only about 8 mg cm-3 which is comparable to the most lightweight silica aerogels and distinctly lower than all values for cellulosic aerogels obtained from plant cellulose so far. SEM, ESEM and nitrogen adsorption experiments at 77 K reveal an open-porous network structure that consists of a comparatively high percentage of large mesopores and small...

2010-01-01

71

High-energy cosmic-ray nuclei from high- and low-luminosity gamma-ray bursts and implications for multi-messenger astronomy  

CERN Document Server

Gamma-ray burst (GRB) is one of the candidates of high-energy cosmic-ray acceleration sites. They may be also ultra-high-energy (above 3 EeV) cosmic-ray (UHECR) sources. In this paper, we discuss possibilities and implications of high-energy cosmic-ray acceleration in GRBs. (1) First, we show that not only protons but also heavier nuclei can be accelerated up to ultra-high energies in both usual high-luminosity (HL) and low-luminosity (LL) GRBs by using the Geant4. LL GRBs may also make a significant contribution to the observed UHECR flux if they form a distinct population, and we investigate cosmic-ray acceleration in LL GRBs in detail. (2) Second, we discuss implications of the GRB-UHECR hypothesis (and Hypernova-UHECR hypothesis) to cosmic-ray astronomy. HL GRBs and LL GRBs will lead to different source number densities as UHECR sources, so that the determination of the number ...

2008-01-01

72

Development of a fine and ultra-fine group cell calculation code SLAROM-UF for fast reactor analyses  

International Nuclear Information System (INIS)

A cell calculation code SLAROM-UF has been developed for fast reactor analyses to produce effective cross sections with high accuracy in practical computing time, taking full advantage of fine and ultra-fine group calculation schemes. The fine group calculation covers the whole energy range in a maximum of 900-group structure. The structure is finer above 52.5 keV with a minimum lethargy width of 0.008. The ultra-fine group calculation solves the slowing down equation below 52.5 keV to treat resonance structures directly and precisely including resonance interference effects. Effective cross sections obtained in the two calculations are combined to produce effective cross sections over the entire energy range. Calculation accuracy and improvements from conventional 70-group cell calculation results were investigated through comparisons with reference values obtained with continuous energy Monte Carlo calculations. It was ...

2006-08-01

73

The investigations on K and L X-ray fluorescence parameters of gold compounds  

British Library Electronic Table of Contents (United Kingdom)

The study aimed to determine the chemical effects on the K and L X-ray intensity ratios and the K and L X-ray production cross sections for gold compounds. The K shell fluorescence yields and L shell average yields were also investigated. The samples were excited by 59.5keV ?-rays from an 241Am annular radioactive source and 123.6keV ?-rays from a 57Co annular radioactive source. K and L X-rays emitted from samples were counted by an Ultra-LEGe detector with a resolution of 0.150keV at 5.9keV. The experimental values were compared with theoretical, the semi-empirical and other experimental values.

2010-01-01

74

Identification of fatigue damage in cortical bone by diffraction enhanced imaging  

International Nuclear Information System (INIS)

In an effort to explore Diffraction Enhanced Imaging of bone tissue, experiments were performed to determine if it was possible to use Diffraction Enhanced Imaging to detect microdamage in bovine cortical bone. Measurements were made at the National Synchrotron Light Source where pre- and post-fatigue rocking curve widths of the bone were studied. The rocking curve widths were then compared. Since no consistent pattern of narrowing or broadening of the rocking curve emerged, it is likely that the ultra-small-angle X-ray scattering present in the bone overshadowed any additional changes to rocking curve caused by microdamage of the bone. Larger bone structures were able to be visualized which suggests that microdamage may be visualized with a higher resolution detector.

2005-08-11

75

Ultra high vacuum test setup for electron gun  

Energy Technology Data Exchange (ETDEWEB)

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

2008-05-01

76

Synthesizer Stability Evaluation - NASA Technical Report Server (NTRS)  

Science.gov (United States)

verified via high-resolution spectral density measurements using the Hadamard Variance. .... spectral density measurements were made with the HF5390 ...

77

Self-similarity in NMR Spectra: An Application in Assessing the Level of Cysteine  

UK PubMed Central (United Kingdom)

High resolution of NMR spectroscopic data of biosamples are a rich source of information on the metabolic response to physiological variation or pathological events. There are many advantages...Full Text Available

2010-01-01

78

Science Directed Spacecraft Autonomy for Mars Missions - detail  

Science.gov (United States)

The rapidly growing field of remote sensing is beginning to supply massive amounts of high resolution imagery of the earth and other planets. ...

79

Postfire soil burn severity mapping with hyperspectral image unmixing  

Science.gov (United States)

Sep 28, 2011... to assess the application of high resolution imagery for burn severity mapping and to compare it to standard burn severity mapping methods. ...

81

NASA Satellite Measures Deforestation : Image of the Day  

Science.gov (United States)

Sep 14, 2005 ... For decades, the Brazilian government has been basing estimates of Amazon deforestation on high-resolution Landsat satellite data. Having ...

83

High resolution (p,p') reactions on "8"7Sr and "8"8Sr  

International Nuclear Information System (INIS)

... levels excited states mev range 10-100 proton reactions proton spectra protons

84

High Resolution Modeling of Coastal Inundation: User ...  

Science.gov (United States)

... Ruth. Preller@nrlssc.navy.mil 76 Marine Technology Society Journal Page 4. ... 78 Marine Technology Society Journal Page 6. ...

2007-07-27

85

C-CAP Land Cover, Commonwealth of the Northern Mariana Islands (CNMI), Farallon de Pajaros, 2004  

Science.gov (United States)

This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change ... ...

86

C-CAP Land Cover, Commonwealth of the Northern Mariana Islands (CNMI), Anatahan, 2005  

Science.gov (United States)

This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change ... ...

87

C-CAP Land Cover, Commonwealth of the Northern Mariana Islands (CNMI), Aguijan, 2003  

Science.gov (United States)

This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change ... ...

88

Benefits of Using the Photosimulation Laboratory Environment ...  

Science.gov (United States)

... with the ability to capture imagery in raw 24-bit format, combined with large memory storage devices enable high resolution imagery to be captured ...

2002-08-01

89

Acquisition of a High Resolution Field Emission Scanning Electron Microscope for the Analysis of Returned Samples  

Science.gov (United States)

This grant furnished funds to purchase a state-of-the-art scanning electron microscope (SEM) to

2003-01-01

90

A setup for high-resolution isotope shift measurements on unstable lithium isotopes  

Energy Technology Data Exchange (ETDEWEB)

We present a laser spectroscopic approach for measuring the charge radius of the halo nucleus {sup 11}Li and report on recent progress in the development of the experimental apparatus.

2003-05-01

91

2010 NASA Terrestrial Ecology Science Team Meeting - NASA Carbon ...  

Science.gov (United States)

The biomass maps were compared with the U.S. Forest Service biomass map for 2002 , LVIS height data, and estimates from high resolution imagery. ...

92

2002 C-CAP Land Cover, Territory of American Samoa, Swains  

Science.gov (United States)

This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change ... ...

93

Method of defining features on materials with a femtosecond laser  

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a pulsed laser ablation method of metals and/or dielectric films from the surface of a wafer, printed circuit board or a hybrid substrate. By utilizing a high-energy ultra-short pulses of laser light, such a method can be used to manufacture electronic circuits and/or electro-mechanical assemblies without affecting the material adjacent to the ablation zone.

2006-05-23

94

Ultrashallow P{sup +}/N junction formation by plasma ion implantation  

Energy Technology Data Exchange (ETDEWEB)

We investigated the electrical characteristics and the junction depth of ultra-shallow junctions formed by using the plasma-doping method. Compared with ultra-low energy boron-ion implantation at 500 eV, the junctions formed with the plasma-doping process exhibited shallow junction depths and low sheet resistances. The junction depths of the plasma-doped samples were 150 A and 330 A after annealing for 10 s at 900 .deg. C and 950 .deg. C, respectively. For the same junction depth, the sheet resistance of the B{sub 2}H{sub 6} plasma-doped sample was an order of magnitude less than that of the 500-eV B-ion implanted sample. Cross-sectional transmission electron microscopy and deep level transient spectroscopy showed that the defects formed by the B{sub 2}H{sub 6} plasma-doping process could be removed by annealing at 950 .deg. C for 10 s. The scaling of metal-oxide-semiconductor field-effect-transistor (MOSFET) device channel lengths for ...

2000-12-01

95

Ultrashallow P"+/N junction formation by plasma ion implantation  

International Nuclear Information System (INIS)

We investigated the electrical characteristics and the junction depth of ultra-shallow junctions formed by using the plasma-doping method. Compared with ultra-low energy boron-ion implantation at 500 eV, the junctions formed with the plasma-doping process exhibited shallow junction depths and low sheet resistances. The junction depths of the plasma-doped samples were 150 A and 330 A after annealing for 10 s at 900 .deg. C and 950 .deg. C, respectively. For the same junction depth, the sheet resistance of the B_2H_6 plasma-doped sample was an order of magnitude less than that of the 500-eV B-ion implanted sample. Cross-sectional transmission electron microscopy and deep level transient spectroscopy showed that the defects formed by the B_2H_6 plasma-doping process could be removed by annealing at 950 .deg. C for 10 s. The scaling of metal-oxide-semiconductor field-effect-transistor (MOSFET) device channel lengths for ...

2000-12-01

96

High-resolution primary ion beam probe for SIMS  

Energy Technology Data Exchange (ETDEWEB)

High-brightness negative ion beams, especially O{sup -} beams, from a compact gaseous plasma source are studied to evaluate the suitability for high-resolution SIMS. Ion-optical calculations are made using the beam parameters from the new source. Results suggest that sub-100 nm spot with O{sup -} beam current of 10 pA is achievable. Beam focusing, the resulting beam current distributions at the target and the expected instrumental performance are discussed.

2004-06-15

97

Oxygen stabilization induced enhancement in superconducting characteristics of high-Tc oxides  

International Nuclear Information System (INIS)

In an attempt to enhance the electrical and mechanical properties of the high temperature superconducting oxides, high T(sub c) composites were prepared composed of the 123 compounds and AgO. The presence of extra oxygen due to the decomposition of AgO at high temperature is found to stabilize the superconducting 123 phase. Ag is found to serve as clean flux for grain growth and precipitates as pinning center. Consequently, almost two orders of magnitude enhancement in critical current densities were also observed in these composites. In addition, these composites also show much improvement in workability and shape formation. On the other hand, proper oxygen treatment of Y5Ba6Cu11Oy was found to possibly stabilize superconducting phase with T(sub c) near 250 K. I-V, ac susceptibility, and electrical resistivity measurements indicate the existence of this ultra high T(sub c) phase in ...

1991-01-01

98

Metabolomics in Lung Inflammation: A High Resolution 1H NMR Study of Mice Exposed to Silica Dust  

UK PubMed Central (United Kingdom)

Here we report the first 1H NMR metabolomics studies on excised lungs and bronchoalveolar lavage fluid (BALF) from mice exposed to crystalline silica. High resolution 1H...Full Text Available

2008-01-01

99

High resolution neutron imaging of water in the polymer electrolyte fuel cell membrane  

Energy Technology Data Exchange (ETDEWEB)

Water transport in the ionomeric membrane, typically Nafion{reg_sign}, has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, high resolution neutron imaging of the Nafion{reg_sign} membrane is presented in order to measure water content and through-plane gradients in situ under disparate temperature and humidification conditions.

2009-01-01

100

High resolution imagery of the clumpy irregular galaxy Markarian 325 = NGC 7673  

Energy Technology Data Exchange (ETDEWEB)

High resolution imagery of the clumpy irregular galaxy Mkn 325 shows that some clumps have sizes approximately 300 pc while some may still be unresolved and approximately < 100 pc. In spite of dimensions comparable to - or even smaller than - those of the giant H II complex 30 Doradus, one clump has a star formation rate 100 times higher.

1982-05-01

101

High resolution imagery of the clumpy irregular galaxy Markarian 325 = NGC 7673  

International Nuclear Information System (INIS)

High resolution imagery of the clumpy irregular galaxy Mkn 325 shows that some clumps have sizes approximately 300 pc while some may still be unresolved and approximately < 100 pc. In spite of dimensions comparable to - or even smaller than - those of the giant H II complex 30 Doradus, one clump has a star formation rate 100 times higher. (author).

102

Technologies for high speed rolling and control of gauge in cold tandem mill for ultra-thin gauge strip; Gokuusu reikan atsuenki ni okeru kosoku atsuen gijutsu oyobi itaatsu seigyo gijutsu  

Energy Technology Data Exchange (ETDEWEB)

This paper describes high speed rolling and gauge control in cold tandem mill for ultra-thin gauge strip at the Chiba Works of Kawasaki Steel Corporation. To improve the plate-out property of rolling oil, cationic polymeric coagulant was prepared. Rolling oil with cohesion independent of inorganic inclusions or phosphatide was developed, to improve the lubrication for cold rolling, remarkably. In addition, a low-cost Ti-enhanced work roll having high wear resistance and excellent grindability was developed. Rolling can be conducted at the optimal rolling roughness and operation can be performed at the highest rolling speed independent of the rolling treatment amount. Rolling speed at 2800 m/min was confirmed by developing the rolling oil with excellent lubrication and the work roll having high wear resistance. For the improvement of strip thickness accuracy at the steady state rolling, use of the backup ...

1996-09-01

103

Effect of V and W addition on the high temperature strength properties of 12%Cr-15%Mn austenitic steels. 12%Cr-15%Mn austenite ko no ondo kyodo ni oyobosu V to W tenka no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Experimental discussions were given on effect of V and W addition on the high temperature strength properties of 12% Cr-15% Mn austenite steels. The test samples were added with W at 0% to 3.5% and V at 0% to 0.5% in addition to C and N, and were given aging treatment or solution treatment. This paper describes the following matters on the results of high-temperature strength measurements and structural observation: A remarkable trend was observed that M23 Cb type carbides precipitate in the aging treatment, wherein aging hardening appears prominently which is attributable to ultra-fine deposits of vanadium nitride (VN) in the V-added material; the V addition is very effective in increasing the high-temperature tensile strength and creep fracture strength as compared with single W addition, wherein the said carbides that accelerate the precipitation as a result of the V addition make a large ...

1992-11-01

104

High resolution Computed Tomography in the study of temporal bone trauma  

International Nuclear Information System (INIS)

Thirty-five patients with temporal bone fractures were examined; the fractures were sometimes associated with dislocation of the assicular chain caused by road fatalities. Computed Tomography (CT) was performed either because of the presence of clinical symptoms associated with trauma of the temporal bone, because of a hemotympanum discovered during a CT scan of the brain. Thirty-three fractures were detected: 19 longitudinal, 6 transverse, and 8 complex. An incudostapedial dislocation was also detected, together with a displacement of a stapedial prosthesis from the lenticular process of incus, and 3 incus-malleus dislocation associated with fractures. High resolution CT allows the precise definition of the course of the fractures, of the associated dislocation of the ossicular chain, and of facial nerve lesion, thus allowing a more accurate surgical intervention. In the examination of the temporal bone, high ...

1988-01-01

105

PROBING NEAR-SURFACE ATMOSPHERIC TURBULENCE WITH LIDAR MEASUREMENTS AND HIGH-RESOLUTION HYDRODYNAMIC MODELS  

Energy Technology Data Exchange (ETDEWEB)

As lidar technology is able to provide fast data collection at a resolution of meters in an atmospheric volume, it is imperative to promote a modeling counterpart of the lidar capability. This paper describes an integrated capability based on data from a scanning water vapor lidar and a high-resolution hydrodynamic model (HIGRAD) equipped with a visualization routine (VIEWER) that simulates the lidar scanning. The purpose is to better understand the spatial and temporal representativeness of the lidar measurements and, in turn, to extend their utility in studying turbulence fields in the atmospheric boundary layer. Raman lidar water vapor data collected over the Pacific warm pool and the simulations with the HIGRAD code are used for identifying the underlying physics and potential aliasing effects of spatially resolved lidar measurements. This capability also helps improve the trade-off between spatial-temporal resolution ...

2000-11-01

106

Reduced resolution polarimetric imagery characterization of the 1990 Galveston Bay oil spill  

Energy Technology Data Exchange (ETDEWEB)

Low resolution visual polarimetric photographic imagery of the Galveston Bay oil spill from a tanker accident on July 28, 1990 was obtained and analyzed. The low resolution imagery (30 to 100 meters) was obtained concurrently with high resolution (1 meter), and is representative of what would be seen by a polarimetric satellite. Orthogonal red-green-blue (RGB) polarimetric images obtained with color photography were digitized by KODALUX on to a CD ROM. These polarimetric images were then used to calculate the percent polarization. The positive and negative percent polarized radiation scattered by each of the sea surface waves is seen individually in high resolution imagery. (Percent polarization is defined as positive when the dominant radiation is perpendicular to the plane of incidence and negative when it is parallel). The analysis of low ...

1997-06-01

107

Tandem repeats analysis for the high resolution phylogenetic analysis of Yersinia pestis  

UK PubMed Central (United Kingdom)

BackgroundYersinia pestis, the agent of plague, is a young and highly monomorphic species. Three biovars, each one thought to be associated with the last three Y....Full Text Available

108

Inferring transcription factor complexes from ChIP-seq data  

UK PubMed Central (United Kingdom)

Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) allows researchers to determine the genome-wide binding locations of individual transcription factors (TFs) at high resolution....Full Text Available

2011-08-01

109

Studies of ultra-low energy electron-molecule collisions using very-high-n Rydberg atoms  

International Nuclear Information System (INIS)

Potassium atoms in selected high-lying np Rydberg states (80 #<=# n #<=# 400) are being used as a tool to examine electron-polar molecule collisions at ultra-low energies (#approx#80 #mu#eV - 1 meV). This energy regime has not been investigated previously and is of interest because the corresponding electron de Broglie wavelength is large, #approx#1300 - 330 Angstrom, and because the collision time is comparable to the period of molecular rotation. A variety of target molecules has been studied, including simple rotors such as HF, and more complex species such as NH_3, CH_3I, CH_2Br_2 and C_6H_5NO_2. These targets encompass a range of dipole moments and rotational behavior, but analysis of the data shows that in each case the cross section #sigma#(#epsilon#) for rotationally-inelastic electron-polar molecule scattering varies approximately as 1/#epsilon# where #epsilon# is the electron energy. Such threshold behavior is not predicted by ...

1993-05-16

110

Analysis of algorithms for ultra high speed relays for the protection of high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

The object of this research is the evaluation of the performance of ultra high speed relays (UHSR's) used for protection of a-c transmission lines. For purposes of this report, these are relays whose response time is less than a quarter of a cycle of the 60 Hz wave (i.e. 4.167 ms.). To identify relaying schemes that may comply with this definition, a literature survey was undertaken. The selected relays were studied in detail and modeled on a digital computer. A theoretical description of these relays is presented. Records of real transient data as well as of simulated data were used as input to the digital models of relays. The real data were recorded by means of monitoring stations connected to the Florida Power and Light Company transmission lines. The simulated data were obtained by modeling the relevant parts of the utility's transmission system using a University of British Columbia simplified version of the well known ...

1984-01-01

111

Spherically bent crystal spectroscopy in laser-produced plasma  

International Nuclear Information System (INIS)

A curved crystal X-ray spectrographs of reflection type spherical geometry was required based on the Johann scheme. Due to their high efficiency and resolution, X-ray spectrographs of focusing spectrograph spatial resolution are suitable for detecting weak X-ray spectra in spectrometers for laser fusion research. Spherically bent mica crystal with a radius of curvature of 380 mm was used in the spectrometer. The Bragg angle of the crystal analyzer was 51 degree. The image plate was employed to obtain high spatial resolution and a narrow spectral band width, with an effective area of 30 mm x 80 mm. The designed optical path of the X-ray spectrometer beam was 980 mm long from the source to the crystal and the detector. The first experiment was carried out at the 20 J energy laser facility of Research Center of Laser Fusion, China Academy of Engineering Physics. X-ray spectra in an ...

2008-02-01

112

Ultra-thin lithium micro-batteries. Performances and applications; Microaccumulateurs ultra minces au lithium. Performances et applications  

Energy Technology Data Exchange (ETDEWEB)

This short paper (abstract) describes the characteristics and performances of prototypes of ultra-thin lithium micro-batteries (thickness < 0.2 mm) which can be incorporated into microelectronic circuits. (J.S.)

1996-12-31

113

A high-sensitivity small animal SPECT system  

International Nuclear Information System (INIS)

Medical imaging using single gamma-ray-emitting radionuclides typically makes use of parallel hole collimators or pinholes in order to achieve good spatial resolution. However, a tradeoff in sensitivity is inherent in the use of a collimator, and modern preclinical single photon emission computed tomography (SPECT) systems detect a very small fraction of emitted gamma rays, often less than 0.1%. A system for small animal SPECT imaging which uses no collimators could potentially achieve very high sensitivity-several tens of percent-with reasonably sized detectors. This would allow two significant improvements in preclinical studies: images could be obtained more rapidly, allowing higher throughput for screening applications, or for dynamic processes to be observed with very good time resolution; and images could be obtained with less radioactive tracer, making possible the in vivo imaging of low-capacity receptor systems, ...

2009-03-07

114

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

Energy Technology Data Exchange (ETDEWEB)

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

2007-06-04

115

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

International Nuclear Information System (INIS)

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

2007-06-04

116

Field-portable lensfree tomographic microscope.  

Science.gov (United States)

We present a field-portable lensfree tomographic microscope, which can achieve sectional imaging of a large volume (?20 mm(3)) on a chip with an axial resolution of Hymenolepis nana egg, which is an infectious parasitic flatworm. Achieving a decent three-dimensional spatial resolution, this field-portable on-chip optical tomographic microscope might provide a useful toolset for telemedicine and high-throughput imaging applications in resource-poor settings. PMID:21573311

2011-05-16

117

Evaluation of peripheral vascular disease by intravenous digital subtraction angiography with the Fuji computed radiography (FCR) system  

Energy Technology Data Exchange (ETDEWEB)

Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management.

1987-03-01

118

Evaluation of peripheral vascular disease by intravenous digital subtraction angiography with the Fuji computed radiography (FCR) system  

International Nuclear Information System (INIS)

Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management. (orig.).

1987-01-01

119

Simulation on energy deposition process due to anisotropic fast electron transport in high density plasma  

International Nuclear Information System (INIS)

Energy deposition process by relativistic fast electrons produced by ultra-intense laser pulses is discussed. The process is calculated with a two dimensional Fokker-Planck simulation code including binary and collective collisions coupled with electromagnetic field. We focused on Velocity Distribution Function (VDF) dependence in the simulation. The results show that the spread angle of the fast electrons distribution affects energy deposition area and deposited energy is concentrated in the vicinity of the propagation axis of the fast electrons. It may be also suggested that self-pinch effect of a fast electron beam causes large deposition energy. (author)

2008-03-01

120

Problems and approach to geological disposal of radioactive waste  

International Nuclear Information System (INIS)

This feature articles described a concept and technical problems of geological disposal of high-level radioactive waste in the civil engineering. It consists of six papers such as the present statues and subjects of geological disposal by KITAYAMA Kazumi, the diastrophism, igneous activity, and upheaval and erosion by YAMAZAKI Haruo, the groundwater flow and evaluation of nuclear transfer by IJIRI Yuji, evaluation of alteration of cement materials in the ultra-long period by HAGA Kazuko, The Mizunami Underground Research Laboratory in course of construction by SAKAMAKI Masanori, and interview of the ninetieth president of JSCE (Japan Society of Civil Engineers), he places his hope on JSCE and civil engineers by KISHI Kiyoshi. (S.Y.)

2006-11-01

121

Multilayer ultra high gradient insulator technology  

Energy Technology Data Exchange (ETDEWEB)

We are investigating a novel insulator concept which involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform many times better (about 1.5 to 4 times higher breakdown electric field) than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present our ongoing studies investigating the degradation of the breakdown electric field resulting from surface roughness, the effect of gas pressure, and the performance of the insulator structure under bi-polar stress. Further, we present our initial modeling studies.

1998-03-27

122

Improved formability of ultra high strength steels through local heat treatment  

Energy Technology Data Exchange (ETDEWEB)

In this paper it is described how a martensitic steel sheet with tensile strength of 1400 MPa is heat treated locally. The sheet is then formed in the heat treated regions in a way that would be impossible with the untreated material. Mechanical properties and forming limit diagrams of the heat treated material are determined and the forming operations are simulated, which shows that the method can be used by designers. Although the method has been known for decades, it remains to be industrialised and the work presented here is to be seen as a contribution to this development. (orig.)

2005-07-01

123

Coverage and large scale anisotropies estimation methods for the Pierre Auger Observatory  

Energy Technology Data Exchange (ETDEWEB)

When searching for anisotropies in the arrival directions of Ultra High Energy Cosmic Rays, one must estimate the number of events expected in each direction of the sky in the case of a perfect isotropy. We present in this article a new method, developed for the Auger Observatory, based on a smooth estimate of the zenith angle distribution obtained from the data itself (which is essentially unchanged in the case of the presence of a large scale anisotropy pattern). We also study the sensitivity of several methods to detect large-scale anisotropies in the cosmic ray arrival direction distribution : Rayleigh analysis, dipole fitting and angular power spectrum estimation.

2005-07-01

124

The ANL X6B beamline at NSLS: A versatile facility  

Energy Technology Data Exchange (ETDEWEB)

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

1994-07-01

125

In-beam #gamma#-ray spectroscopy of fast beams at the NSCL  

International Nuclear Information System (INIS)

With the development of an array of highly-segmented germanium detectors, it now becomes possible to perform in-flight #gamma#-ray spectroscopy experiments on intermediate energy beams with unprecedented #gamma#-ray energy resolution. Presented in this report are examples of two techniques in which SeGA, the most highly-segmented operational germanium array for in-flight spectroscopy with fast beams, was used for the detection of #gamma# rays. SeGA used in conjunction with a high-resolution magnetic spectrograph (S800) to detect the reaction residues in coincidence represents a powerful combination for in-beam #gamma#-ray studies.

2004-04-05

126

High-resolution sequence stratigraphy and its controls on uranium mineralization. Taking middle Jurassic Qingtujing formation in Chaoshui basin as an example  

International Nuclear Information System (INIS)

By applying the high-resolution sequence stratigraphy, the different sub-divisions of base-level cycles of Qingtujing Formation, Middle Jurassic in Chaoshui Basin are analyzed in detail. 23 short, 3 middle and 1 long base-level cycles are recognized. On the above basis, the corresponding frameworks of high-resolution sequence stratigraphy have been established in northern and southern sub-basins respectively, and the detailed sedimentary facies of MSC_1_-_3 and the special distribution of Qintujing Formation are discussed. It is pointed out that MSC_2 is the most favorable layer for the localization of sandstone-type uranium deposits. (authors)

2006-06-01

127

High-resolution NMR on /sup 29/Si nuclei in acidic zeolites  

Science.gov (United States)

The effect of treatment of Na-forms of zeolites with HCl solutions and of heat treatment of their NH/sub 4/-forms on the stability of aluminum-oxygen tetrahedra has been studied in this work by high-resolution NMR on /sup 29/Si nuclei, using the synthetic zeolites X, Y, and M (mordenite) as the objects of the study. The exchange capacity with respect to Na/sup +/ ions was determined by analyzing the equilibrium solutions after contact of the samples with 0.5 NH/sub 4/Cl solution on a flame photometer. The high-resolution /sup 29/Si NMR spectra of polycrystalline samples were recorded on an SKhR-200 spectrometer with a superconducting solenoid at a frequency of 39.75 MHz with ultrafast mechanical rotation (3 kHz) of the sample at the magic angle to the external magnetic field. The results obtained are given.

1986-12-01

128

High speed inverted optical-resolution photoacoustic microscopy  

Science.gov (United States)

Photoacoustic microscopy (PAM) offers label-free, optical absorption contrast. A high-speed, high-resolution PAM system in an inverted microscope configuration with a laser pulse repetition rate of 100,000 Hz and a stationary ultrasonic transducer was built. Four-dimensional in vivo imaging of microcirculation in mouse skin was achieved at 18 three-dimensional volumes per second with repeated two-dimensional raster scans of 100 by 50 points. The corresponding twodimensional B-scan (50 A-lines) frame rate was 1800 Hz, and the one-dimensional A-scan rate was 90,000 Hz. The lateral resolution is 0.23+/-0.03 ?m for Au nano-wire imaging, which is 2.0 times below the diffraction limit.

2011-02-01

129

Development of a new #gamma#-ray detector for PEM applications  

International Nuclear Information System (INIS)

The authors are developing a high specificity detector for detecting the increased metabolic rate of breast tumors. Positron emission mammography (PEM) provides a highly efficient, high spatial resolution positron imaging system. PMT plays a very important role in PEM detectors, because most of the systems consist of scintillator arrays coupled with PMT. Our detector is composed of 20 x 20 arrays of 2 mm x 2 mm x 20 mm of Bi_4Ge_3O_1_2 (BGO) scintillators and a novel flat panel position-sensitive PMT (FP-PS-PMT)-Hamamatsu R8400-00-M256. Spatial resolutions of 2.0 mm FWHW and energy resolutions of 23% FWHM are achieved. (authors)

2007-05-01

130

Automatic Extraction of Open Space Area from High Resolution Urban Satellite Imagery  

CERN Document Server

In the 21st century, Aerial and satellite images are information rich. They are also complex to analyze. For GIS systems, many features require fast and reliable extraction of open space area from high resolution satellite imagery. In this paper we will study efficient and reliable automatic extraction algorithm to find out the open space area from the high resolution urban satellite imagery. This automatic extraction algorithm uses some filters and segmentations and grouping is applying on satellite images. And the result images may use to calculate the total available open space area and the built up area. It may also use to compare the difference between present and past open space area using historical urban satellite images of that same projection

2011-01-01

131

Study of spatial resolution in three-dimensional rotational angiography  

International Nuclear Information System (INIS)

In interventional radiology (IVR) of cerebral aneurysms, it is important to understand the form and physical relationships between the cerebral aneurysm and the surrounding vessels. However, because the vessels in the head area are highly complex, it can be difficult to comprehend the structure using conventional angiography. Therefore, three-dimensional rotational angiography (3D-RA) has been used in recent years. This article discusses studies of the spatial resolution of 3D-RA. We reconstructed 3D-RA of an acrylic slit phantom (slit widths: 0.5, 0.75, 1.0, 1.5 mm) and examined spatial resolution by visual evaluation and profile curves. When the slit phantom was arranged to avoid the effect of beam hardening, the spatial resolution of 3D-RA was found to be as high as 0.75 mm. When the slit phantom was placed orthogonal to the rotational axis of the C-arm, the spatial ...

2006-03-01

132

Leading research on supermetal. Part 1. Large-scale materials (iron system); Super metal no sendo kenkyu. 1. Ogata sozai (tetsukei)  

Energy Technology Data Exchange (ETDEWEB)

Supermetal with critical characteristics is under advanced investigation for further improvement of metal materials. Although iron is most frequently used as structural material among various metals, it should be used more carefully and effectively because of resource limitation and global environmental problem. It is essential to draw various excellent properties much more from iron and to improve recyclability. In particular, the best way to meet these requirements is achievement of more fine structure and higher purity. Since the lowest crystalline grain size is now limited to nearly 10{mu}m, metallic structure composed of grains below 1{mu}m is expected by mesoscopic control. Various methods have been studied to achieve ultra-fine crystalline structure, and study of precise heat treatment control and ultra-strength metallurgy is required. Heat treatment in magnetic field and layered structure by mechanical alloying are also promising. ...

1996-03-01

133

A comparative study on ultra-shallow junction formation using co-implantation with fluorine or carbon in pre-amorphized silicon  

Energy Technology Data Exchange (ETDEWEB)

The main driver in ultra-shallow formation for the 65 nm technology node and beyond is to find solutions that both reduce boron transient enhanced diffusion and can be integrated in the CMOS process flow. To this end, many studies have recently focused on using co-doping techniques with fluorine and most recently with carbon. In most cases, one or both of these is co-implanted with a dopant specie in pre-amorphized silicon. In this work, we show a comparative study of fluorine or carbon co-implanted with low-energy boron to form source and drain extension junctions for PMOS devices. We will show that by a systematic optimization of germanium, boron, fluorine or carbon energies and doses, spike annealing technology can be extended to the 65 nm node. These results will be used to discuss how the different formed junctions offer potential solutions for either low-power or high-performance PMOS device fabrication.

2005-12-05

134

Resolution studies of a GEM-based TPC  

Energy Technology Data Exchange (ETDEWEB)

Currently there are four different concept studies trying to optimise the detector for the requirements at the ILC. In three of these detector concepts a time projection chamber (TPC) is foreseen as the main tracking device. To achieve the intended spatial resolution of 100 {mu}m, micro pattern gas detectors (MPGD) are considered for gas amplification. The two different MPGDs discussed for the ILC TPC are Micro-Mesh Gaseous Detectors (Micromegas) and Gas Electron Multiplier foils (GEMs). The current thesis shows resolution studies with a TPC prototype equipped with a triple GEM readout structure. A hodoscope made up of silicon strip sensors gives a precision reference track, allowing an unbiased measurement of the spatial resolution. High statistics measurements have been conducted at the DESY test beam facility, which provides positrons with a tunable energy between 1 GeV and 6 GeV. Using the ...

2006-12-15

135

Scattered Light from Close-in Extrasolar Planets: Prospects of Detection with the MOST Satellite  

CERN Document Server

The ultra-precise photometric space satellite MOST (Microvariability and Oscillations of STars) will provide the first opportunity to measure the albedos and scattered light curves from known short-period extrasolar planets. Due to the changing phases of an extrasolar planet as it orbits its parent star, the combined light of the planet-star system will vary on the order of tens of micromagnitudes. The amplitude and shape of the resulting light curve is sensitive to the planet's radius and orbital inclination, as well as the composition and size distribution of the scattering particles in the planet's atmosphere. To predict the capabilities of MOST and other planned space missions, we have constructed a series of models of such light curves, improving upon earlier work by incorporating more realistic details such as: limb darkening of the star, intrinsic granulation noise in the star itself, tidal distortion and back-heating, higher angular ...

2003-01-01

136

High-temperature property data: Ferrous alloys  

Energy Technology Data Exchange (ETDEWEB)

In this book over 250 alloys are organized by AISI number into 10 major sections: Irons, Carbon Steels, Alloy Steels, Low Alloy Constructional Steels, Ultra High Strength Steels, Tool Steels, Maraging Steels, Wrought Stainless Steels, Heat Resistnat Casting Alloys, and Iron Based Rought Superalloys. Each alloy record lists the designation, specifications, UNS number, composition, product forms and a comment on the high-temperature properties and applications. Referenced data is then given for physical properties such as density, specific heat, thermal conductivity, thermal expansion, electrical conductivity, Poisson's ratio, moduli of elasticity and rigidity, etc. Mechanical properties follow, and include tensile properties, shearing and bearing properties, impact properties, creep, stress rupture and stress relaxation and fatigue properties. The last part of the alloy record gives other effects of temperature, ...

1987-01-01

137

Embedded systems for vacuum control at PEFP  

International Nuclear Information System (INIS)

Development of a front end system for a high energy proton accelerator is in progress at Korea Atomic Energy Research Institute (KAERI) for basic science and industrial applications. The proper vacuum components has been installed and operated successfully between ion source and RFQ. The reliable operation of the accelerator has been completed at vacuum system in the high and ultra high vacuum range under operating conditions. Proper control system for the vacuum instruments, based on PC operated by Windows, has been designed and constructed by control group at PAL. As PC operated by windows with inherent instability does not proper, embedded system can be replaced for reliable operation system, such as VME system operated by vxWorks.

2005-05-26

138

Double plasma mirror for ultrahigh temporal contrast ultra-intense laser pulses  

International Nuclear Information System (INIS)

We present and characterize a very efficient optical device that employs the plasma mirror technique to increase the contrast of high-power laser systems. Contrast improvements higher than 104 with 50% transmission are shown to be routinely achieved on a typical 10 TW laser system when the pulse is reflected on two consecutive plasma mirrors. Used at the end of the laser system, this double plasma mirror preserves the spatial profile of the initial beam, is unaffected by shot-to-shot fluctuations, and is suitable for most high peak power laser systems. We use the generation of high-order harmonics as an effective test for the contrast improvement produced by the double plasma mirrors. (authors)

140

Fostering the commercialization of ultra capacitors  

Energy Technology Data Exchange (ETDEWEB)

This document presents the activity of KiloFarad International (KFI), a trade association for the promotion of the interests of the international ultra-capacitor industry through education and representation. KFI provides a forum for the ultra-capacitor industry to work on non-competitive activities (standards, working groups, test procedures etc..). The rest of the document presents some informations about ultra-capacitors technology and some advanced applications in the automotive and telecommunication industries. (J.S.)

2004-07-01

141

Study of Stent Deployment Mechanics Using a High-Resolution X-ray Imaging Detector  

UK PubMed Central (United Kingdom)

To treat or prevent some of the 795,000 annual strokes in the U.S., self-expanding endo-vascular stents deployed under fluoroscopic image guidance are often used. Neuro-interventionalists need...Full Text Available

2011-03-01

142

Solid-state 13C NMR spectroscopy of a 13C carbonyl-labeled polypeptide  

UK PubMed Central (United Kingdom)

High resolution structural elucidation of macromolecular structure by solid-state nuclear magnetic resonance requires the preparation of uniformly aligned samples that are isotopically labeled. In...Full Text Available

1992-06-01

143

Semiconductor Radiation Detectors with Frisch Collars and Collimators for Gamma Ray Spectroscopy and Imaging  

Energy Technology Data Exchange (ETDEWEB)

To study CdZnTe as a high energy resolution gamma ray detector with a novel new design, and to build a detector array from the new detector design

2006-12-04

144

Research in heavy-ion nuclear physics  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.

1992-01-01

145

Photophysics and optical switching in green fluorescent protein mutants  

UK PubMed Central (United Kingdom)

We demonstrate by using low-temperature high-resolution spectroscopy that red-shifted mutants of green fluorescent protein are photo-interconverted among three conformations and are, therefore, not...Full Text Available

2000-03-28

146

NAME=\\  

Wastenet

... Buckeye rapidly produces high resolution imagery over a commander's area of interest contributing to intelligence, surveillance and reconnaissance, and also creates detailed mapping of the battlespace. BIG uses an innovative, original and creative combination of Web programming languages, Geographic Information Systems, and ...

147

NAME=\\  

Wastenet

...because it had greatly contributed to the geospatial capability of coalition forces in the Global War on Terrorism by producing a system that provides high-resolution imagery for use in detecting ground changes, creating detailed maps and obtaining Intelligence, Surveillance and Reconnaissance (ISR) information. ...

148

NAME=\\  

Wastenet

...Quality = $290,604 to improve permit compliance and appropriate preservation of wetlands by providing a spatial dataset to locate individual wetland permits on a property using high resolution imagery within specific regions of Virginia; this data set will be compared with the permit Comprehensive Environmental Database System that is currently used ...

149

Longitudinally and circumferentially directed movements of the left ventricle studied by cardiovascular magnetic resonance phase contrast velocity mapping  

UK PubMed Central (United Kingdom)

ObjectiveUsing high resolution cardiovascular magnetic resonance (CMR), we aimed to detect new details of left ventricular (LV) systolic and diastolic function, to explain the twisting...Full Text Available

150

Laser-assisted solar-cell metallization processing  

Energy Technology Data Exchange (ETDEWEB)

Laser assisted solar cell metallization processing which is a one step process is examined. The potential advantages of laser disposition techniques for photovoltaic systems are: a high resolution, no photolithography, clean and contamination free, in-situ sintering, and low contact resistance.

1984-03-01

151

Joint Research Centre - JRC - European Commission  

Wastenet

... The high resolution imagery , collected over Rio de Janeiro, Brazil, included a mixture of large commercial buildings and private houses, as well as the airport and some community parks. 10/08/11 Read more Top EU R&D companies expect a 5% ...

152

High-resolution sequence stratigraphic character and sandstone-type uranium ore formation. A case from Saihan Formation in Baiyinwula area, Erlian Basin  

International Nuclear Information System (INIS)

High-resolution sequence stratigraphy has been applied widely in the petroleum exploration and development, many achievements have been achieved. However, it is in the beginning stage that high-resolution sequence stratigraphy is applied to explore the sandstone-type uranium deposits in Erlian Basin. By applying principles of high-resolution sequence stratigraphy and taking typical boreholes as an example, sedimentary cycles of Saihan Formation, the ore-bearing formation in Baiyinwula area are divided and correlated through cross sections. One long-term cycle (LSC_1), two middle-term cycles (MSC_1, MSC_2) have been identified in this study. Based on this and combined with the mineralization character of sandstone uranium deposits in this area, it is presented that the interlayer oxidation zone is developed mainly in the rising hemicycle of MSC_1 and uranium ore bodies predominantly in channel sand bodies that were developed ...

2006-12-01

153

Gravitropism: Interaction of Sensitivity Modulation and Effector Redistribution 1  

UK PubMed Central (United Kingdom)

Our increasing capabilities for quantitative hormone analysis and automated high resolution growth studies have allowed a reassessment of the classical Cholodny-Went hypothesis of gravitropism. According...Full Text Available

1991-01-01

154

Epilogue - GES DISC - NASA  

Science.gov (United States)

Sep 9, 2009... a French Ariane rocket successfully launched a new Earth-observing satellite ... The payload is a pair of identical sensors known as "high-resolution ... the resulting image) are activated simultaneously by incoming radiation; ...

155

Bragg curves of fission fragments in gases  

Energy Technology Data Exchange (ETDEWEB)

An unexpectedly high probability of collisions between the fission particles and the atoms in an ionization chamber along the entire particle track causes a strong fluctuation of the shapes of the Bragg curves. This fluctuation imposes an upper limit of the charge resolution ..delta..Z/Z which can be achieved.

1986-03-01

156

14 - NASA  

Science.gov (United States)

... and mean rainfall rates, Rm, in the liquid hydrometeor layers using the .... large latitudinal movement of cirrus cloud cover with the changing seasons. ... We study the statistical distribution of PSCs by particle composition using .... the high resolution Cloud Particle Imager (CPI) and standard PMS 2D-C and ...

157

A new application of MRT of the lung using ultra-shot turbo spin echo sequences (UTSE); Ein neuer Ansatz in der Magnetresonanztomographie der Lunge mit einer ultrakurzen Turbo-Spin-Echo-Sequenz (UTSE)  

Energy Technology Data Exchange (ETDEWEB)

T{sub 2} weighted ultra-short turbo spin echo sequences were used in five individuals with variations in echo times, delayed triggering and echo intervals. To reduce movement artifacts all examinations were carried out with ECG and respiratory triggering. The sequences giving optimal image quality were then employed in 19 patients having various pulmonary abnormalities. Image resolutions, artifacts, image contrasts and diagnostic value were then judged by two observers and compared with CT. In the first study, a diastole-triggered UTSE sequence with the shortest echo proved optimal (T{sub E}=90 ms, T{sub R}=2-4 s, echo=9 ms, turbo factor=19). In the patient series studied, MRT was inferior to CT with regard to resolution and number of artifacts, but better in respect of contrast and diagnostic value. Using UTSE of the lung, MRT can produce images of good quality. Compared with CT, contrast is better with MRT, offering ...

1996-05-01

158

High resolution transmission electron microscopy of partial states of oxygen order in YBa_2Cu_3O_z  

International Nuclear Information System (INIS)

This paper reports on high resolution electron microscopy used to investigate the effect of electron irradiation induced oxygen loss on the states of partial order in YBa_2Cu_3O_z. Contrast effects visible in the [001] zone image as a result of the degree of the out-of-plane correlation of these ordered states are investigated. Using statistical simulations to aid in the analysis of the HREM images, an interpretation based on a kinetically limited evolution of the variation of long range [001] ordering is proposed.

1990-04-16

159

High Resolution Eddy Current Probes for Non Destructive Testing  

Science.gov (United States)

New industrial Non Destructive Testing requires the development of new probes: technologies such as high spatial resolution probes for small breaking flaws detection or flexible probes for complex curved surfaces inspection. The CEA/LIST has designed and integrated 2 probes to answer industrial's constraints. The first one is based on Giant Magneto-Resistance and is able to detect 50 ?m3 flaws. The second one is based on micro-coils etched on kapton and its flexibility is adapted to curved surfaces inspection. Both are multi-elements probes, allowing fast inspection. This paper presents those new probes, their design and their performances.

2008-02-01

160

Gaussian models for genetic linkage analysis using complete high-resolution maps of identity by descent  

Energy Technology Data Exchange (ETDEWEB)

Gaussian-process models are developed to detect genetic linkage using complete high-resolution maps of identity by descent between affected relative pairs. Approximations are given for the significance level and power of the likelihood-ratio test of no linkage and for likelihood-ratio confidence regions for trait loci. The sample sizes required to detect linkage by using different classes of affected relative pairs are compared, and the problem of combining data from different classes of relatives is discussed. 23 refs., 2 figs.

1993-07-01

161

The Development of Meteorological Data Fields for the Radiological Emergency Preparedness  

Energy Technology Data Exchange (ETDEWEB)

In this study we tried to develop the long-range transport system and find the way to prevent from the radiological emergency risk. For the study, meteorological forecast system in Korea Meteorological Administration is investigated. Numerical simulation is also carried out by the long-range transport model and Vis-5D. We surveyed the emergency preparedness for nuclear accidents which were ARAC in USA, RODOS in Europe and WSPEED in Japan and then investigated the processing of medium- and long-range atmospheric diffusion modeling system. We also studied on the application of KMA/NWPD model which are GDAPS and RDAPS. In the future, it is necessary to produce to the high resolution meteorological data from KMA/NWPD for the development of medium- and long-range atmospheric diffusion modeling system and construct the integrated system for data processing in real time. It was simulated by using micro-scale meteorological field applying wind field ...

2000-04-01

162

Noise bias in the refinement of structures derived from single particles  

Energy Technology Data Exchange (ETDEWEB)

One of the main goals in the determination of three-dimensional macromolecular structures from electron microscope images of individual molecules and complexes (single particles) is a sufficiently high spatial resolution, about 4 A, at which the interpretation with an atomic model becomes possible. To reach high resolution, an iterative refinement procedure using an expectation maximization algorithm is often used that leads to a more accurate alignment of the positional and orientational parameters for each particle. We show here the results of refinement algorithms that use a phase residual, a linear correlation coefficient, or a weighted correlation coefficient to align individual particles. The algorithms were applied to computer-generated data sets that contained projections from model structures, as well as noise. The algorithms show different degrees of over-fitting, especially at ...

2004-12-15

163

Spin-resolved magnetic studies of focused ion beam etched nano-sized magnetic structures  

International Nuclear Information System (INIS)

Scanning ion microscopy with polarization analysis (SIMPA) is used to study the spin-resolved surface magnetic structure of nano-sized magnetic systems. SIMPA is utilized for in situ topographic and spin-resolved magnetic domain imaging as well as for focused ion beam (FIB) etching of desired structures in magnetic or non-magnetic systems. Ultra-thin Co films are deposited on surfaces of Si(1 0 0) substrates, and ultra-thin, tri-layered, bct Fe(1 0 0)/Mn/bct Fe(1 0 0) wedged magnetic structures are deposited on fcc Pd(1 0 0) substrates. SIMPA experiments clearly show that ion-induced electrons emitted from magnetic surfaces exhibit non-zero electron spin polarization (ESP), whereas electrons emitted from non-magnetic surfaces such as Si and Pd exhibit zero ESP, which can be used to calibrate sputtering rates in situ. We report on new, spin-resolved magnetic microstructures, such as magnetic 'C' states and magnetic vortices, found at surfaces of ...

2005-04-01

164

Enhancement of Heat and Mass Transfer in Mechanically Contstrained Ultra Thin Films  

Energy Technology Data Exchange (ETDEWEB)

Oregon State University (OSU) and the Pacific Northwest National Laboratory (PNNL) were funded by the U.S. Department of Energy to conduct research focused on resolving the key technical issues that limited the deployment of efficient and extremely compact microtechnology based heat actuated absorption heat pumps and gas absorbers. Success in demonstrating these technologies will reduce the main barriers to the deployment of a technology that can significantly reduce energy consumption in the building, automotive and industrial sectors while providing a technology that can improve our ability to sequester CO{sub 2}. The proposed research cost $939,477. $539,477 of the proposed amount funded research conducted at OSU while the balance ($400,000) was used at PNNL. The project lasted 42 months and started in April 2001. Recent developments at the Pacific Northwest National Laboratory and Oregon State University suggest that the performance of absorption and desorption systems can be ...

2005-01-01

165

Ultratrace determination in high purity molybdenum and tungsten with ion chromatographic trace-matrix-separation. Pt. 2; Ultra trace analysis using ion chromatography. Ultraspurenanalytik in hochreinem Molybdaen und Wolfram mit ionenchromatographischer Spuren-Matrix-Trennung. Tl. 2; Ionenchromatographische Ultraspurenanalyse  

Energy Technology Data Exchange (ETDEWEB)

The use of high-performance ion exchangers allows a trace-matrix-separation (SMT) directly followed by an ion chromatographic (IC) separation of the analytes. Based on the principles described in Part 1, a combined procedure IC-SMT-IC for metallic impurities in Mo and W is presented. Up to 12 metal traces (Fe, Cu, Pb, Zn, Ni, Co, Cd, Ca, Mn, Sr, Mg and Ba) can be determined in one run with 35 min. A special method for traces of U and Th is also given. Detection limits are typically 10-100 ng g{sup -1} in the metal sample. (author). 14 refs.; 10 figs.; 6 tabs.

1992-01-31

166

Ultra high strength beta titanium alloy for fasteners  

International Nuclear Information System (INIS)

A new high strength titanium alloy has been developed primarily intended for fastener applications. While Ti-6Al-4V is used extensively as a fastener alloy in the aerospace industry, its shear strength allowable is limited to 655 MPa (95 ksi). For higher shear strength requirements, various steels or nickel-based alloys are used (up to 860 MPa (125 ksi)), but with the attendant density penalty. This new alloy is intended to provide the 860 MPa shear strength at roughly a 40% weight savings. After screening various alloy systems, the optimum chemistry has been selected as follows: Ti-6.0V-6.2Mo-5.7Fe-3Al. In light of its 125 ksi shear strength goal, the alloy has been designated TIMETAL reg-sign 125.

1993-02-21

167

Hot dip galvanised dual phase steels for automotive applications  

Energy Technology Data Exchange (ETDEWEB)

The automotive industry desires to optimize safety and lightweight construction for the production of cars and trucks. The resulting task for steel suppliers is to make steel grades available that can fulfil these requirements. Different projects have shown optimistic outlooks for optimization of safety and reduction of the weight of automobile bodies by using different high strength and ultra high strength steels. In the last group the dual phase steels play the lead. In recent years different steel grades have been developed and optimized for these applications. On one hand developing the mechanical properties as well as joining and forming of dual phase steels is one of the first steps. On the other hand different coated surfaces for various applications of dual phase steels is another step. Starting with characteristic production conditions for cold rolled hot dip galvanised dual phase steels, the mechanical properties ...

2005-07-01

168

High-throughput proteomics of breast carcinoma cells: a focus on FTICR-MS  

Energy Technology Data Exchange (ETDEWEB)

Discovery of better biomarkers for diagnosis, prognosis, and therapy-response prediction is the most critical task of a scientific quest aimed at developing newly designed, tailor-made therapies for patients with cancer. Consequently, a proteome wide analysis, in addition to genomic studies, is an absolute requirement for a complete functional understanding of tumor biology. Ultra-sensitive, high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) currently holds an important role in fulfilling the demands of biomarker discovery. In this review, we describe the applicability of FTICR MS for breast cancer proteomics, particularly for the analysis of complex protein mixtures obtained from a limited number of cells typically available from clinical specimens.

2008-06-05

169

High-Throughput Screening of Drugs of Abuse in Urine by Supported Liquid?Liquid Extraction and UHPLC Coupled to Tandem MS  

British Library Electronic Table of Contents (United Kingdom)

A qualitative method, involving supported liquid?liquid extraction (SLE) and ultra high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS?MS), was developed for the rapid tentative identification of various drugs of abuse in urine. In this study, 28 drugs and metabolites were covered by the screening procedure. Before analysis, urine samples were extracted by SLE and good extraction recoveries were obtained for most investigated compounds. The UHPLC strategy was then selected for the rapid separation of amphetamines, cocaine, opiates and related compounds in urine. Using columns packed with sub-2??m particles, analysis time was reduced down to 2?min, while maintaining acceptable performance. Finally, the detection was by tandem MS operating in the single reaction...

2009-01-01

170

Very high resolution measurements of the total cross section of natural iron  

Energy Technology Data Exchange (ETDEWEB)

The total cross section of natural Fe has been measured with the GELINA pulsed white neutron source with a time-of-flight resolution of about 3.8 ps/m and good statistical precision. Measurements have been performed on three sample thicknesses including one with an average transmission of 0.1, in order to check for consistency and for remaining resolution effects. The cross sections in the {open_quotes}unresolved resonance region{close_quotes} still show rather strong fluctuations. These data will directly be used in shielding benchmark calculations. The resonance region data will be analysed by an R-matrix routine and the parameters be compared to existing compilations.

1994-12-31

171

Quadrant anode image sensor  

Science.gov (United States)

A position-sensitive event-counting electronic readout system for microchannel plates (MCPs) is described that offers the advantages of high spatial resolution and fast time resolution. The technique relies upon a four-quadrant electron-collecting anode located behind the output face of the microchannel plate, so that the electron cloud from each detected event is partly intercepted by each of the four quadrants. The relative amounts of charge collected by each quadrant depend on event position, permitting each event to be localized with two ratio circuits. A prototype quadrant anode system for ion, electron, and extreme ultraviolet imaging is described. The spatial resolution achieved, approx. =10 ..mu.., allows individual MCP channels to be distinguished. (AIP)

1976-11-01

172

Quadrant anode image sensor  

International Nuclear Information System (INIS)

A position-sensitive event-counting electronic readout system for microchannel plates (MCPs) is described that offers the advantages of high spatial resolution and fast time resolution. The technique relies upon a four-quadrant electron-collecting anode located behind the output face of the microchannel plate, so that the electron cloud from each detected event is partly intercepted by each of the four quadrants. The relative amounts of charge collected by each quadrant depend on event position, permitting each event to be localized with two ratio circuits. A prototype quadrant anode system for ion, electron, and extreme ultraviolet imaging is described. The spatial resolution achieved, approx. =10 #mu#, allows individual MCP channels to be distinguished.

9472-01-01

173

PERFORMANCE-LIMITING DEFECTS IN CDZNTE DETECTORS.  

Energy Technology Data Exchange (ETDEWEB)

We studied the effects of small, <20 {micro}m, Te inclusions on the energy resolution of CdZnTe gamma-ray detectors using a highly collimated X-ray beam and gamma-rays, and modeled them via a simplified geometrical approach. Previous reports demonstrated that Te inclusions of about a few microns in diameter degraded the charge-transport properties and uniformity of CdZnTe detectors. The goal of this work was to understand the extent to which randomly distributed Te-rich inclusions affect the energy resolution of CZT detectors, and to define new steps to overcome their deleterious effects. We used a phenomenological model, which depends on several adjustable parameters, to reproduce the experimentally measured effects of inclusions on energy resolution. We also were able to hound the materials-related problem and predict the enhancement in performance expected by reducing the size and number of Te ...

2006-10-29

174

High resolution alpha-particle spectroscopy using CR-39 plastic track detector  

Energy Technology Data Exchange (ETDEWEB)

A technique has been developed for high resolution alpha particle spectroscopy from track length determination in CR-39 plastic. On individual tracks an energy resolution deltaE close to the range straggling limit is obtainable. For 6 MeV alpha-particle deltaE is proportional 35 keV on individual particles and for groups of particles deltaE proportional 20 keV can be achieved using certain data selection criteria. At 100 keV on individual particles deltaE is proportional 20 keV. The analysis requires 1) a knowledge of the track-etch rate (Vsub(T))-range relationship and 2) a theoretical understanding of alpha-particle track structure in CR-39 as a function of particle energy, dip angle and degree of etching. The structure of alpha-particle etched tracks in CR-39 is described and two methods of analysis discussed. Examples are given of the resolution attainable on tracks of alpha-particles as natural ...

1984-06-15

175

Detailed comparison of the structures and kinematics of simulated and observed barred galaxies  

CERN Document Server

We examine the observable properties of simulated barred galaxies including radial mass profiles, edge-on structure and kinematics, bar lengths and pattern speed evolution for detailed comparison to real systems. We have run several simulations in which bars are created through inherent instabilities in self-consistent simulations of a realistic disc+halo galaxy model with a disc-dominated, flat rotation curve. These simulations were run at high (N=20M particles) and low (N=500K) resolution to test numerical convergence. We determine the pattern speeds in simulations directly from the phase angle of the bar versus time and the Tremaine-Weinberg method. Fundamental dynamics do not change between the high and low resolution, suggesting that convergence has been reached in this case. We find the higher resolution is needed to simulate structural and kinematic properties accurately. The ...

2003-01-01

176

Pulse Rise Time Characterization of a High Pressure Xenon Gamma Detector for use in Resolution Enhancement  

CERN Document Server

High pressure xenon ionization chamber detectors are possible alternatives to traditional thallium doped sodium iodide (NaI(Tl)) and hyperpure germanium as gamma spectrometers in certain applications. Xenon detectors incorporating a Frisch grid exhibit energy resolutions comparable to cadmium/zinc/telluride (CZT) (e.g. 2% (at) 662keV) but with far greater sensitive volumes. The Frisch grid reduces the position dependence of the anode pulse risetimes, but it also increases the detector vibration sensitivity, anode capacitance, voltage requirements and mechanical complexity. We have been investigating the possibility of eliminating the grid electrode in high-pressure xenon detectors and preserving the high energy resolution using electronic risetime compensation methods. A two-electrode cylindrical high pressure xenon gamma detector coupled to time-to-amplitude ...

2000-01-01

177

Production of a helium beam in a focused ion beam machine using an electron beam ion trap  

International Nuclear Information System (INIS)

Gallium liquid-metal ion sources that have been introduced in the late 1970s have allowed the development of a new class of micro- and nanofabrication tools collectively denominated as focused ion beam (FIB) machines. To investigate the potential of a helium beam in such a FIB instrument the authors have tested a room-temperature electron beam ion trap coupled with a high resolution FIB machine. In this letter they present their first results in target imaging using a helium beam with a resolution that allows to account for a beam diameter in the submicrometer range.

2007-02-19

178

The application of high resolution sequence stratigraphy to reservoir zonation and management of the Beryl Field  

Energy Technology Data Exchange (ETDEWEB)

Tidally dominated sections from the Middle Jurassic Beryl Formation of the Beryl Field, Viking Graben (UKCS) were deposited during rapid changes in relative sea level. High density well coverage in this key producing interval has allowed the construction of an integrated high resolution sequence stratigraphic scheme based on sedimentological, ichnofaunal, wireline, biostratigraphic and engineering data. From this database a number of high resolution sequences in the Bajocian-Bathonian Beryl Formation have been identified composed of interbedded sandstones, siltstones and mudstones. These sediments formed tidally-influenced deltas and estuaries deposited in actively subsiding half-grabens during regionally extensive base-level changes. For reservoir management purposes, the formation has been split into 5 units. The thickest interval, Unit 3, is considered here. In the northern part ...

1996-08-01

179

Status and potential of materials development as reflected in steels for the automotive industry; Stand und Potential der Werkstoffentwicklung am Beispiel der Staehle fuer die Automobilindustrie  

Energy Technology Data Exchange (ETDEWEB)

The high-strength and ultra high-strength steels developed and produced by Thyssen Krupp Stahl make a major contribution to automotive lightweighting. Proven and newly-developed coatings are used to meet increasingly important corrosion protection requirements. Design for materials, optimized forming and joining processes and the use of modern simulation techniques help to exploit the potential of the new steels. Future development work will focus on reducing the density of steels without compromising their well-known advantages - in particular their strength. The use of high-strength and ultra high-strength steels in the automotive industry is on the increase. Steel will remain the material of choice for auto manufacture, above all due to its potential for cost-efficient lightweight construction and its full recyclability. (orig.) [German] Einen wesentlichen ...

1999-04-01

180

Issues on boron electrical activation in silicon: Experiments on boron clusters and shallow junctions formation  

Energy Technology Data Exchange (ETDEWEB)

A comprehensive understanding of dopant activation mechanisms in crystalline Si is required in order to form shallow junctions. In this paper, we will review several experimental assessments on boron clustering and novel methods to form shallow junctions. Boron marker-layer structures have been used to investigate the fundamental aspects of formation and ripening boron-interstitial clusters (BICs) and their influence on the associated transient enhanced diffusion (TED). The samples were damaged by Si implants at different doses in the sub-amorphizing range and annealed at high temperatures. We found that BICs act as a sink for interstitials at supersaturations values S(t)>10{sup 4}. This implies that silicon self-interstitial defects are the primary source of interstitials driving TED, and that BICs act as a secondary 'buffer' for the interstitial supersaturation. These clusters are less sensitive to the ripening process than pure ...

2002-01-01

181

Lymph node staging in cervical carcinoma: Results of high resolution MRT with phased-array coil  

International Nuclear Information System (INIS)

Purpose: To determine the diagnostic value of high resolution MR imaging with a circularly polarised (c.p.) body phased-array coil for the staging of pelvic lymph nodes in cervical carcinoma. Material and methods: 42 patients with histologically proven carcinoma of the cervix were studied on a 1.5 T scanner by using a c.p. body phased-array coil. The imaging protocol included T_2-weighted turbo-spin-echo (TSE) and T_1-weighted spin-echo sequences pre and post IV application of Gd-DTPA; slice thickness was 5-7 mm and pixel size 0.53 mm"2. Lymph nodes with a diameter of #>=#8 mm were considered to have metastatic involvement. MR imaging results were compared with histopathologic findings. Results: MR imaging showed enlarged lymph nodes (#>=# 8 mm) in 16 of 18 patients with histologic proof of lymph node metastases (sensitivity 89%). In 22 of 24 cases MR findings were true negative (specificity 92%). Diagnostic accuracy was 91%. Conclusion: ...

182

Use of fuel cells to meet military requirements for mobile power  

International Nuclear Information System (INIS)

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

2004-09-25

183

High-performance hybrid pervaporation membranes with superior hydrothermal and acid stability  

Energy Technology Data Exchange (ETDEWEB)

A new organic-inorganic hybrid membrane has been prepared with exceptional performance in dewatering applications. The only precursor used in the sol-gel synthesis of the selective layer was organically linked 1,2-bis(triethoxysilyl)ethane (BTESE). The microporous structure of this layer enables selective molecular sieving of small molecules from larger ones. In the dehydration of n-butanol with 5% of water, the membrane shows a high separation factor of over 4000 and ultra-fast water transport at a rate of more than 20 kg m{sup -2} h{sup -1} at 150C. This can be related to the high adsorption capacity of the material and the sub-micron thickness of the selective layer. The selectivity has now remained constant over almost one and a half years under continuous process testing conditions. Apart from the hydrothermal stability, the membrane exhibits a high tolerance for acid contamination. A slow ...

2009-05-15

184

Untersuchungen zur Anwendung von UHPFRC-Tubbingen bei der zweischaligen Tunnelbauweise  

British Library Electronic Table of Contents (United Kingdom)

Faserbewehrter Beton wird heute zunehmend auch bei Tunnelbauwerken (Tunnelinnenschalen, Tubbinge) eingesetzt. Wesentliche Vorteile sind das hohe Tragvermogen, das daraus entstehende Einsparungspotential an herkommlicher stabformiger Bewehrung (Biegebewehrung, Bugelbewehrung in der Randzone), die Aufnahme von Spaltzugbeanspruchungen durch die Fasern, Rissbreitenbegrenzung, erhohte Dauerhaftigkeit, verbesserter Brandwiderstand (insbesondere bei Verwendung von Kunststofffasern), Optimierung der Arbeitsablaufe etc. Neue Entwicklungen in der Betontechnologie haben in den letzten Jahrzehnten den faserbewehrten ultrahochfesten Beton (engl. UHPFRC - Ultra High Performance Fibre Reinforced Concrete) hervorgebracht. Im Rahmen dieser Arbeit wird der Einsatz des ultrahochfesten, stahlfaserbewehrten Be...

2010-01-01

185

Pulsed laser deposition of titanium-carbonitride thin films  

Energy Technology Data Exchange (ETDEWEB)

The goal of this research program is to determine whether pulsed laser deposition is an effective alternative method for growing TiCN thin films. Pulsed laser deposition (PLD) is chosen because of its well-documented capability for growing uniform, stoichiometric films in ultra-high vacuum or gaseous environments. Processing of thin films by PLD is also achieved at relatively low temperatures compared with CVD processing. Given these attributes, the primary objectives in this article are to determine whether nitrogen may be readily incorporated into films resulting from the laser-ablation of TiC in an N{sub 2} environment, determine what effect nitrogen has on mechanical properties, and determine whether nitrogen incorporation is strongly influenced by processes unrelated to laser deposition (e.g., thermally-activated surface reactions).

1997-05-15

186

Photodegradation of flupentixol in aqueous solution under irradiation at 254nm: Identification of the photoproducts generated  

British Library Electronic Table of Contents (United Kingdom)

After irradiation at 254nm of aqueous solutions of the antipsychotic drug flupentixol, the structures of the photodegradation products were determined by ultra high performance liquid-chromatography linked to mass spectrometry. Fragmentation patterns of the parent ions were established on a hybrid linear ion trap-orbitrap mass spectrometer allowing accurate mass measurements of both parent and daughter ions. This allowed to propose plausible structures for the main photolysis products of flupentixol. A total of nine photoproducts were detected after irradiation of the drug. The main photoproduct is generated following the addition of a hydroxyl group on the double bond adjacent to the thioxanthene ring. Secondary photoproducts were also observed.

2010-01-01

187

Optimized pre-amorphization conditions for the formation of highly activated ultra shallow junctions in silicon-on insulator  

International Nuclear Information System (INIS)

Pre-amorphization of ultrashallow implanted boron in Silicon-on-insulator is optimized to produce an abrupt box-like doping profile with negligible electrical deactivation and significantly reduced transient enhanced diffusion. The effect is achieved by positioning the as-implanted amorphous/crystalline interface close to the buried oxide interface, to minimize interstitials whilst leaving a single-crystal seed to support solid-phase epitaxy. Based on a simple physical model of our results, we estimate that the interface between the Si overlayer and the buried oxide is an efficient interstitial sink with a recombination length of the order of 10nm or less under our experimental conditions. (author)

2008-12-01

188

Empirical regularities of order placement in the Chinese stock market  

CERN Document Server

Using ultra-high-frequency data extracted from the order flows of 23 stocks traded on the Shenzhen Stock Exchange, we study the empirical regularities of order placement in the opening call auction, cool period and continuous auction. The distributions of relative logarithmic prices against reference prices in the three time periods are qualitatively the same with quantitative discrepancies. The order placement behavior is asymmetric between buyers and sellers and between the inside-the-book orders and outside-the-book orders. In addition, the conditional distributions of relative prices in the continuous auction are independent of the bid-ask spread and volatility. These findings are crucial to build an empirical behavioral microscopic model based on order flows for Chinese stocks.

2007-01-01

189

Development of In-Service Inspection system for heat transfer tubes in the primary pressurized water cooler in the HTTR  

International Nuclear Information System (INIS)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

1999-08-22

190

Development of In-Service Inspection system for heat transfer tubes in the primary pressurized water cooler in the HTTR  

Energy Technology Data Exchange (ETDEWEB)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

1999-08-01

191

Influence of intracavity doppler frequency shift in the swept-cavity ringdown spectroscopy incorporating continuous-wave laser excitation  

International Nuclear Information System (INIS)

Cavity ringdown spectroscopy (CRDS) with continuous-wave (cw) laser excitation has added high frequency resolution to the ability of CRDS being used for the absolute quantification of trace-level species present in many chemical processes. Cavity dithering technique has easily resolved the problem of resonant coupling of a cw laser light into a high-finesse cavity. The present study addresses the potential uncertainty involved in such cw-CRDS techniques incorporating the cavity mirror motion, i.e., the doppler frequency shift of a probe light inside the cavity. In the high-resolution spectroscopic work of megahertz-accuracy, even the influence of intracavity doppler effect may become significant.

2001-11-01

192

Creation of nitrogen-vacancy centres in diamond with high resolution  

International Nuclear Information System (INIS)

Nowadays, diamond and the nitrogen-vacancy (NV) colour centres constitute the best solid-state system in view of quantum-computing applications. It has also been shown recently that single NV centres could be used as nanoscale magnetic sensors. Such applications require the creation of single NV centres with very high resolution and with a high efficiency. The nano-implanter at the university of Bochum provides low energy nitrogen ions which can be implanted through a hole pierced in the tip of an atomic force microscope. Ultrapure diamond samples have been implanted with spot sizes of 50nm and less. Stimulated Emission Depletion (STED) microscopy has been used to characterise and resolve the implanted spots.

2010-03-21

193

The different structural scales of the breast and their impact on time-of-flight and diffraction tomography  

Energy Technology Data Exchange (ETDEWEB)

Ultrasound tomography is an attractive imaging method for the detection of breast cancer. The complex anatomy of the breast with its different spatial scales and material property contrasts make accurate reconstructions very challenging. This paper proposes a hybrid approach whereby Travel-of-Flight and Diffraction Tomography are combined together to achieve high-resolution and high-accuracy sound-speed reconstructions. The method is validated with several numerical phantoms.

2010-01-01

194

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

International Nuclear Information System (INIS)

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

2007-12-17

195

An ADP proposal to study the formation and evolution of dust-embedded clusters. Final report  

International Nuclear Information System (INIS)

Using high resolution and high sensitivity IRAS data at 12 and 25 microns low mass stars were studied which have recently formed in the Ophiuchus, Corona Australis, and IC1396 dark clouds. The successful application of these techniques to the Rho Ophiuchi infrared cluster is briefly described. The status of research performed is also presented.

196

A High-Wavenumber Viscosity for High-Resolution Numerical Methods  

Energy Technology Data Exchange (ETDEWEB)

Numerical simulations of compressible flows are commonly based on the Euler equations when effects of viscosity are thought to be negligible. These equations admit singular solutions, even in cases where the initial and boundary conditions are smooth. So-called ''Euler solvers'' rely on numerical dissipation, explicitly or implicitly present in the scheme, to regularize the problem, such that physical solutions are selected.

2003-02-19

197

Investigation of techniques to improve continuous air monitors under conditions of high dust loading in environmental setting. 1998 annual progress report  

Energy Technology Data Exchange (ETDEWEB)

'Improvement in understanding of the deposition of ambient dust particles on ECAM (Environmental Continuous Air Monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAM''s with increased sensitivity under dusty outdoor conditions. As of May 1, 1998 (1/2 year into the project) the research-prototype 30-cm pulsed ionization chamber (PIC) is assembled and operational with an alpha particle energy resolution of better than 45 keV for 5-MeV alpha particles. Measurements of spectral resolution for alpha particles from radon decay products have been made as a function of filter type and dust loading conditions. So far, a study of ten filter types has found that the best combination of resolution and throughput is obtained with 3.0 \\265m Millipore fluoropore and 1.0 \\265m Corning ...

1998-06-01

198

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

Energy Technology Data Exchange (ETDEWEB)

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

2007-04-15

199

Energy resolution of scintillation detectors readout with large area avalanche photodiodes and photomultipliers  

International Nuclear Information System (INIS)

The energy resolution of small NaI(Tl), CsI(Tl), BGO, GSO, YAP and LSO crystals has been studied using 16 mm diameter large area avalanche photodiodes (LAAPD) and a 52 mm diameter photomultiplier. The best result of 4.8% for 662 keV #gamma#-rays from a "1"3"7Cs source was obtained with a 9 mm in diameter by 9 mm high CsI(Tl) scintillator coupled to an LAAPD. Measuring the number of primary electron-hole pairs produced in the LAAPD and photoelectrons in the photomultiplier, as well as the noise contribution of the LAAPD, allowed a quantitative discussion of the results. The energy resolutions measured with LAAPDs are comparable to, or significantly better (at certain emission wavelengths) than, those obtained with the photomultiplier. At energies above 100 keV the energy resolution measured with the majority of crystals and the LAAPD was weakly affected by the photodiode noise contribution. The ...

1998-06-01

200

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

Energy Technology Data Exchange (ETDEWEB)

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

1998-08-01

201

Ultra-high temperature strength properties on Mod.9Cr-1Mo steel  

Energy Technology Data Exchange (ETDEWEB)

A sodium-water reaction drove from the single tube break in steam generator of FBR might overheat labor tubes rapidly under internal pressure loadings. If the temperature of tube wall becomes too high, it has to be evaluated that the stress of tube does not exceed the material strength limit to prevent the propagation of tube rupture. This study clarified the tensile and creep properties of Mod.9Cr-1Mo steel at ultra-high temperature which will be used in evaluation of the tube burst by sodium-water reaction. The strain rates for tensile test are from 10%/min to 10%/sec, and creep-rupture time is maximum 277sec. The range of test temperature is 700degC to 1300degC. The main results obtained were as follows; (1) The evaluation data on the relationship between tensile strength and strain rate and creep-rupture strength in shorter time on Mod.9Cr-1Mo steel were acquired. (2) Short-term mechanical properties of Mod.9Cr-1Mo steel were evaluated ...

2000-03-01

202

Hybrid electric vehicles and electrochemical storage systems - a technology push-pull couple  

Energy Technology Data Exchange (ETDEWEB)

In the advance of fuel cell electric vehicles (EV), hybrid electric vehicles (HEV) can contribute to reduced emissions and energy consumption of personal cars as a short term solution. Trade-offs reveal better emission control for series hybrid vehicles, while parallel hybrid vehicles with different drive trains may significantly reduce fuel consumption as well. At present, costs and marketing considerations favor parallel hybrid vehicles making use of small, high power batteries. With ultra high power density cells in development, exceeding 1 kW/kg, high power batteries can be provided by adapting a technology closely related to consumer cell production. Energy consumption and emissions may benefit from regenerative braking and smoothing of the internal combustion engine (ICE) response as well, with limited additional battery weight. High power supercapacitors may assist the ...

1999-12-01

203

The Complex Interstellar Na I Absorption toward h and Chi Persei  

CERN Document Server

Recent high spatial and spectral resolution investigations of the diffuse interstellar medium (ISM) have found significant evidence for small-scale variations in the interstellar gas on scales less than or equal to 1 pc. To better understand the nature of small-scale variations in the ISM, we have used the KPNO WIYN Hydra multi-object spectrograph, which has a mapping advantage over the single-axis, single-scale limitations of studies using high proper motion stars and binary stars, to obtain moderate resolution (~12 km/s) interstellar Na I D absorption spectra of 172 stars toward the double open cluster h and Chi Persei. All of the sightlines toward the 150 stars with spectra that reveal absorption from the Perseus spiral arm show different interstellar Na I D absorption profiles in the Perseus arm gas. Additionally, we have utilized the KPNO Coude Feed spectrograph to obtain ...

2004-01-01

204

Reverse time migration: resolution in cross well seismic surveys; Migracao reversa no tempo: resolucao em levantamentos sismicos interpocos  

Energy Technology Data Exchange (ETDEWEB)

The standards mapping methods are limited by the lack of information between surface measures and wells profiles. The cross well seismic survey has proven being an effective high-resolution method for reservoirs characterization due its high frequency band. In this work, a 2-D finite differences algorithm for numerical cross well seismic simulation was developed, based in the approach of 2nd order for the time derivatives and 4th order for the space derivatives. In relation to the imaging techniques, it was introduced a reverse time migration method based in the solutions of the wave equation in time for cross well seismic data by the method of the finite differences exclusively. The results of reverse time migration has showed that layers with 90 cm thickness for P-waves could be visualized in migrated sections with excellent resolution. The high frequency cross well seismic data combined with reverse ...

2003-07-01

205

Pseudocraters as indicators of ground ice on Mars  

International Nuclear Information System (INIS)

Positive identification of Martian pseudocraters would be a strong indication of past occurrence of ice at or near the surface of Mars. The basis for suggesting that small cones on Mars are pseudocraters includes: (1) small size, (2) abundant but patchy distribution on what appear to be volcanic plains, (3) presence of other features suggestive of surface or subsurface ice, (4) morphological similarities to Icelandic pseudocraters, and (5) the similarity in distribution of crater/cone diameter ratios to Icelandic pseudocraters. This last morphometric parameter may be the most important, since other possible small terrestrial volcanic analogs have very different crater/cone diameter ratio distributions. In a survey of the available high resolution Viking Orbiter imagery, abundant fields of possible pseudocraters were found. However, only a small fraction of the plains forming units imaged at high ...

1987-05-01

206

Selection of ancillary data to derive production management units in sweet corn (Zea Mays var. rugosa) using MANOVA and an information criterion  

British Library Electronic Table of Contents (United Kingdom)

In production systems where high-resolution harvest data are unavailable there is often a reliance on ancillary information to generate potential management units. In these situations correct identification of relevant sources of data is important to minimize cost to the grower. For three fields in a sweet corn production system in central NSW, Australia, several sets of high-resolution data were obtained using soil and crop canopy sensors. Management units were derived by k-means classification for 2?5 classes using three approaches: (1) with soil data, (2) with crop data and (3) a combination of both soil and crop data. Crop quantity and quality were sampled manually, and the sample data were related to the different management units using multivariate analysis of variance (MANOVA). The ...

2011-01-01

207

Seismic stratigraphy in high resolution shallow marine seismic data of the Gemlik Gulf  

Energy Technology Data Exchange (ETDEWEB)

Seismic stratigraphy and sedimentological studies of the Gemlik Gulf in the Sea of Marmara, Turkey, have been carried out. For this purpose, 19 lines totaling 189 km of excellent quality, high-resolution seismic data were recorded. Four major acoustic units were identified in the seismic profiles. Three were sedimentary units: irregular layered, cross-layered and well-layered; and the fourth was an acoustic basement which is probably composed of crystalline volcanic rocks. Some local areas in the Neogene formation contain gas accumulations. The formation of faults in E--W and N--S directions can be explained by the existence of shear stresses in the Gulf. The bathymetric map shows good accommodation with the shore line as does the tectonic map.

1993-10-01

208

Role of MRI in the diagnostic evaluation of parotid diseases  

International Nuclear Information System (INIS)

MRI findings in 13 patients with monolateral parotid tumor were compared with US, sialographic and CT findings. MRI did not allow an accurate diagnosis in 2 patients with diffuse chronic parotitis. MRI was superior to CT in 1 case in defining the intraglandular site of the lesion, and in 2 patients in showing the extraglandular involvement. MRI proved to be superior to CT thanks to its contrast resolution and to multiplanar imaging. MRI high contrast resolution made it possible to demonstrate neoplastic lesions of 4 mm in diameter. The lesion has low signal intensity on T1-weighted images and high signal intensity on T2-weighted. Parotid tumors cannot be characterized by signal intensity alone: only morphology allows to discriminate between benign and malignant lesions. To conclude, US is a screening method, while MRI is helpful in detecting multifocal lesions and in evaluating the tumor extent.

1988-01-01

209

Real time neutron radioscopy - trends and applications  

International Nuclear Information System (INIS)

Real Time Radiography (RTR) finds extensive applications for inspection of objects on assembly lines for rapid inspection. A typical RTR widely used includes a image intensifier, CCD camera, image processor and high resolution TV monitor in addition to radiographic source. Image intensifiers used in X-radiography employ CsI as the input detector. With the increased use of neutrons as radiation source, real time neutron radiography is also being practised widely. Image intensifiers used in neutron radiography employ gadolinium as the input screen. The neutron image intensifier system at the authors laboratory essentially consists of a 9 inch Trifield image intensifier tube, motorised zoom lens, CCD camera and a high resolution TV monitor

2003-11-12

210

Quantification of order in the liquid at a solid-liquid interface by High-Resolution Transmission Electron Microscopy (HRTEM)  

Energy Technology Data Exchange (ETDEWEB)

A number of different theoretical approaches have been used to model to atomic structure and properties of solid-liquid interfaces. Most calculations indicate that ordering occurs in the first several layers of the liquid, adjacent to the crystal surface. In contrast to the numerous theoretical investigations, there have been no direct experimental observations of the atomic structure of a solid-liquid interface for comparison. Saka et al. examined solid-liquid interfaces in In and In-Sb at lattice-fringe resolution in the TEM, but their data do not reveal information about the atomic structure of the liquid phase. The purpose of this study is to determine the atomic structure of a solid-liquid interface using a highly viscous supercooled liquid, i.e., a crystal-amorphous interface.

1996-12-31

211

Investigations of microstructure of thin TbFeCo films by high-resolution electron microscopy  

International Nuclear Information System (INIS)

High-resolution electron microscope observations confirm the presence of small crystallites in thin TbFeCo films protected by Si_3N_4 overcoats. Selected area electron diffraction patterns in top-view projection indicate that the crystals have a face-centered-cubic structure. Microscope analysis reveals grain growth following annealing of these protected thin films at 200 degree C in vacuum, and Kerr measurements yield large reductions in coercivity relative to the room-temperature value. The typical grain size visible in top-view observations increases from about 3 nm in the as-deposited samples to about 30 nm after annealing at 200 degree C for 36 h while the static coercivity, H_c, drops by about 40%. The fcc structure of the crystals is retained after annealing.

212

High-resolution spectroscopy of Er{sup 3+} ions in 6H SiC  

Energy Technology Data Exchange (ETDEWEB)

In this work, we present results of a systematic study of optical properties of Er{sup 3+} ions in 6H SiC. The role of N-donors played in activation of photoluminescence (PL) of erbium at 1.5 {mu}m was investigated. We have confirmed that N-donors are necessary for activation of the Er PL on one hand, whereas on the other we present evidence that N-donors compete for excitation with Er centres. The high-resolution measurements of the Er{sup 3+} PL were performed aiming at determination of crystal field split levels of the {sup 4}I{sub 15/2} ground and {sup 4}I{sub 13/2} first excited multiplet of Er{sup 3+} ions. Careful analysis of temperature evolution of individual PL lines allowed proposing energy level schemes for the ground and first excited states.

2003-12-15

213

High-resolution spectroscopy of Er"3"+ ions in 6H SiC  

International Nuclear Information System (INIS)

In this work, we present results of a systematic study of optical properties of Er"3"+ ions in 6H SiC. The role of N-donors played in activation of photoluminescence (PL) of erbium at 1.5 #mu#m was investigated. We have confirmed that N-donors are necessary for activation of the Er PL on one hand, whereas on the other we present evidence that N-donors compete for excitation with Er centres. The high-resolution measurements of the Er"3"+ PL were performed aiming at determination of crystal field split levels of the "4I_1_5_/_2 ground and "4I_1_3_/_2 first excited multiplet of Er"3"+ ions. Careful analysis of temperature evolution of individual PL lines allowed proposing energy level schemes for the ground and first excited states.

2003-12-15

214

High-resolution sequence stratigraphic framework and its characteristic. Case study of C-P coal measures in Hebei  

Energy Technology Data Exchange (ETDEWEB)

The framework of time-sequence stratigraphy was established according to the point of view of high-resolution sequence stratigraphy. The development characteristic of the sequence, the distribution pattern of strata, the basin evolution and filling, and the relationship between variations of base level and coal accumulation of epicontinental basin were expounded based on the base-level cycles. The result shows that the C-P coal measures in Hebei is a series of basin deposit of inner epicontinental sea. The formation and evolution and sedimentation of the basin is intimately related to the changes of the basin base-level, which controls the development of the coal-accumulation, forming a clear coal-bearing sequence in the cycle. 9 refs., 3 figs.

2001-07-01

215

High resolution gamma-ray spectrometry of culverts containing transuranic waste at the Savannah River Site  

Energy Technology Data Exchange (ETDEWEB)

A number of concrete culverts used to retrievably store drummed, dry, radioactive waste at the Savannah River Site (SRS), were suspected of containing ambiguous quantities of transuranic (TRU) nuclides. These culverts were assayed in place for Pu-239 content using thermal and fast neutron counting techniques. High resolution gamma-ray spectroscopy on 17 culverts, having neutron emission rates several times higher than expected, showed characteristic gamma-ray signatures of neutron emitters other than Pu-239 (e.g., Pu-238, Pu/Be, or Am/Be neutron sources). This study confirmed the Pu-239 content of the culverts with anomalous neutron rates and established limits on the Pu-239 mass in each of the 17 suspect culverts by in-field, non-intrusive gamma-ray measurements.

1990-01-01

216

High resolution gamma-ray spectrometry of culverts containing transuranic waste at the Savannah River Site  

Energy Technology Data Exchange (ETDEWEB)

A number of concrete culverts used to retrievably store drummed, dry, radioactive waste at the Savannah River Site (SRS), were suspected of containing ambiguous quantities of transuranic (TRU) nuclides. These culverts were assayed in place for Pu-239 content using thermal and fast neutron counting techniques. High resolution gamma-ray spectroscopy on 17 culverts, having neutron emission rates several times higher than expected, showed characteristic gamma-ray signatures of neutron emitters other than Pu-239 (e.g., Pu-238, Pu/Be, or Am/Be neutron sources). This study confirmed the Pu-239 content of the culverts with anomalous neutron rates and established limits on the Pu-239 mass in each of the 17 suspect culverts by in-field, non-intrusive gamma-ray measurements.

1990-12-31

217

High resolution electron microscopy study of as-prepared and annealed tungsten-carbon multilayers  

International Nuclear Information System (INIS)

A series of sputtered tungsten-carbon multilayer structures with periods ranging from 2 to 12 nm in the as-prepared state and after annealing at 500 degrees C for 4 hours has been studied with high resolution transmission electron microscopy. The evolution with annealing of the microstructure of these multilayers depends on their period.As-prepared structures appear predominantly amorphous from TEM imaging and diffraction. Annealing results in crystallization of the W-rich layers into WC in the larger period samples, and less complete or no crystallization in the smaller period samples. X-ray scattering reveals that annealing expands the period in a systematic way. The layers remain remarkably well-defined after annealing under these conditions.

218

High resolution X ray spectroscopy in light antiprotonic atoms  

Energy Technology Data Exchange (ETDEWEB)

At the LEAR facility, CERN, antiprotonic L{alpha} transitions in light elements have been investigated with a focussing crystal spectrometer. The high resolution of the experiment allowed for the first time to resolve in p-barH the 2{sup 3}P{sub 0} state from the close lying states 2{sup 3}P{sub 2}, 2{sup 1}P{sub 1}, and 2{sup 3}P{sub 1}. In p-barD the corresponding transitions were found to be more than an order of magnitude broader. To a large extent the results for p-barH support the meson exchange model.

2000-08-15

219

Behavior of triterpenes from Maytenus aquifolium Martius ('espinheira santa') upon X- and gamma-rays irradiation  

International Nuclear Information System (INIS)

The behavior of the triterpenes friedelin and friedelan-3-ol, contained on the leaves of Maytenus aquifolium Martius (Celastraceae), upon several doses of X- and #gamma#-rays (10 to 100 kGy), was investigated by high resolution gas chromatography (HRGC) and high resolution gas chromatography -mass spectrometry (HRGC-MS). The friedelin content has not changed with #gamma#-irradiation, but the content of friedelan-3-ol decreased around 17% at doses of 10, 20 and 40 kGy and around 27% at doses of 60, 80 and 100 kGy. The levels of both triterpenes remained unchanged even at higher X-ray doses. Lupen-3-one was detected by HRGC-MS. (author).

220

Weld metal as strong as base metal?; Schweisszusatzwerkstoffe koennen/muessen nicht immer die Anforderungen der Grundwerkstoffe erfuellen  

Energy Technology Data Exchange (ETDEWEB)

The development of new steels is always a challenge for the manufacturer of filler metals. In many cases it is obvious that some properties of the base metal cannot be fulfilled with matching filler metals. In some cases, dissimilar filler metals can solve the problem in some cases, there is no chance to meet the requirements of the base metal (for example yield strengths of new ultra high strength steels). This paper deals with different kinds of new steels and the requirements for the weld metal with examples from motor car industry (Mangan Austenite), crane (Ultra high strength steels), earthmoving machinery (Wear-resistant steels) and offshore (Supermartensitic steels). Specific problems will be discussed and best solutions will be highlighted. These examples make clear that the success of new kinds of steels in the market depends on solving the joining problems of these steels. (Abstract Copyright ...

2007-07-15

221

Potent, selective and cell penetrant inhibitors of SF-1 by functional ultra-high-throughput screening.  

Science.gov (United States)

The steroidogenic factor 1 (SF-1, also known as NR5A1) is a transcription factor belonging to the nuclear receptor superfamily. Whereas most of the members of this family have been extensively characterized, the therapeutic potential and pharmacology of SF-1 still remains elusive. Described here is the identification and characterization of selective inhibitory chemical probes of SF-1 by a rational ultra-high-throughput screening (uHTS) strategy. A set of 64,908 compounds from the National Institute of Health's Molecular Libraries Small Molecule Repository was screened in a transactivation cell-based assay employing a chimeric SF-1 construct. Two analogous isoquinolinones, ethyl 2-[2-[2-(2,3-dihydro-1,4-benzodioxin-7-ylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate (SID7969543) and ethyl 2-[2-[2-(1,3-benzodioxol-5-ylmethylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate and (SID7970631), were identified as potent submicromolar inhibitors, yielding ...

2008-03-11

222

Analysis and design of an ultra-high-temperature, hydrogen-fueled MHD generator as an open cycle power supply  

Energy Technology Data Exchange (ETDEWEB)

The theoretical analysis of a partially-ionized hydrogen gas flow (gas temperatures of approximately 10,000 to 20,000 K) through a particular class of magnetohydrodynamic (MHD) generators and the preliminary design of these MHD generators as open cycle, electric power supplies are performed. Analysis of the gas flow through these ultra-high temperature MHD generators requires a coupled gas dynamics/radiative heat transfer solution. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using non-gray, absorbing-emitting two- and three-dimensional P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative heat transfer are coupled through the energy equation, and through the ...

1990-01-01

223

Groundwater penetrating radar and high resolution seismic for locating shallow faults in unconsolidated sediments  

Energy Technology Data Exchange (ETDEWEB)

Faults in shallow, unconsolidated sediments, particularly in coastal plain settings, are very difficult to discern during subsurface exploration yet have critical impact to groundwater flow, contaminant transport and geotechnical evaluations. This paper presents a case study using cross-over geophysical technologies in an area where shallow faulting is probable and known contamination exists. A comparison is made between Wenner and dipole-dipole resistivity data, ground penetrating radar, and high resolution seismic data. Data from these methods were verified with a cone penetrometer investigation for subsurface lithology and compared to existing monitoring well data. Interpretations from these techniques are compared with actual and theoretical shallow faulting found in the literature. The results of this study suggests that (1) the CPT study, combined with the monitoring well data may suggest that discontinuities in correlatable zones may ...

1993-12-31

224

Determination of Proper Peaking Time for Ultra Lege detector at Medium Energies  

International Nuclear Information System (INIS)

Reducing count losses and pile-up pulse effects in quantitative and qualitative analysis is necessary for accuracy of analysis. Therefore, the optimum peaking time for particular detector systems is important. For this purpose, pure Se and Zn elements were excited by 59.5 keV ?-rays from a 50 mCi 241Am annular radioactive source in this study. The characteristic x-rays emitted from pure Se and Zn elements were detected by using an ultra low energy Ge (Ultra-LEGe) detector connecting Tennelec TC 244 spectroscopy amplifier at different peaking time modes. Overall pulse widths were determined by HM 203-7 oscilloscope connecting amplifier. The proper peaking time for ultra low energy germanium detector (Ultra-LEGe) is determined about 4 ?s.

2008-08-25

225

XPS/AES Study of Electrical and Chemical Properties of Pd/SiC Interface  

Science.gov (United States)

Silicon carbide (SiC) based electronic devices are of great importance for applications under the condition of high temperature, high power and high radiation. Schottky diodes of Palladium/SiC are good candidates for hydrogen and hydrocarbon gas sensors at elevated temperature. The detection sensibility of the diodes has been found heavily temperature dependent. In this work, the electrical and chemical properties of Pd/SiC Schottky contacts were studied by XPS and AES at different annealing temperatures. Schottky diodes were made by depositing ultra-thin palladium films onto a silicon carbide substrate. No significant change in the Schottky barrier height of the Pd/SiC contact was found in the temperature range of 300-673K. Palladium diffusion into SiC and the formation of palladium silicides were observed at room temperature and became significant at 300^oC and higher temperature. The mechanism of ...

1997-11-01

226

Ultra high-speed (508 MHz) beam position digital feedback system  

Energy Technology Data Exchange (ETDEWEB)

The B-Factory which is constructed by National Laboratory for High Energy Physics is the device for elucidating the breakdown of symmetry of matter and antimatter by studying the behavior of B mesons which are generated in large quantity when the electrons and the positrons which are accelerated to light velocity level are collided. In order to maintain electron beam-positron beam bunch circling the ring at light velocity stably, the instability of the coupled bunch must be overcome. For this purpose, the ultrahigh speed beam position digital feedback control system was developed. This system is composed of the high speed input-output substrate using GaAs LSI, the feedback computation substrate using complementary metal oxide semiconductor and the memory mounted on it, and the real time operation device. The development of both substrates and their functions are explained. The real time data collection and the change of computation parameters ...

1997-02-01

227

The effects of sacrificial coatings on hydrogen embrittlement and re-embrittlement of ultra high strength steels  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an investigation of electrodeposited Zn-14% Ni and aluminium-based SermeTel 1140/962 coatings as possible replacements for cadmium. Slow strain rate tests were performed to measure the extent of direct hydrogen embrittlement of a high strength steel substrate as a result of the coating process and of hydrogen re-embrittlement caused by coating corrosion. The level of re-embrittlement was shown to depend on both the electrochemical potential of the coating and its barrier properties. Zn-14% Ni coatings caused the most re-embrittlement as they had the most active potential and contained through-thickness defects which left the steel exposed to hydrogen uptake. The microstructure of the high strength steel was also shown to be an important factor affecting the extent of embrittlement. AerMet 100 steel was more resistant than 300M steel and this was attributed to the presence of reverted austenite surrounding the martensite ...

2008-04-15

228

Reducing the costs of ultrapure water production - a case study  

Energy Technology Data Exchange (ETDEWEB)

The 380 MW combined cycle gas turbine power station in Peterborough changed its water supply from town mains to high purity reverse osmosis permeate in October 2000. The high purity water is produced from secondary treated sewage effluent using advanced membrane technology. Alpheus Environmental and British Gas staff have recently completed a study of the power station's demineralization plant to identify the differences in operating costs associated with the change in feedwater. The results show that the ultrapure water produced after the change to a high purity feed is of improved quality and that the demineralization plant regeneration operating costs have been reduced by over 90%. The demineralization plant availability has increased from 78 to 98% enabling almost 20% more ultra pure water to be produced. The change in feedwater has also improved the local environment by significantly ...

2002-02-01

229

Microstructural and mechanical characterization of high energy ball milled and sintered WC-10wt%Co-xTaC nano powders  

British Library Electronic Table of Contents (United Kingdom)

Ultra fine tungsten carbide and cobalt powders were milled by high energy planetary ball mill at different ball to powder weight ratios (BPR) to produce particles of WC-10wt%Co hard metal in nanometer scale size. Microstructural characterizations by TEM show that the particle size of tungsten carbide was achieved to 32nm after milling at 15 BPR during 10h. In order to reduce the WC grain growth during the sintering process, tantalum carbide was added to the hard metal as a WC grain growth inhibitor. The nano hard metal powders were compacted at 200MPa pressure and sintered at 1370-1450degreeC temperatures in a high purity hydrogen atmosphere. The results show that the addition of 0.6wt% of TaC improves the hardness and fracture toughness from 1493 HV30 and 11.8MPam (for TaC free sample) to...

2009-01-01

230

Cold SQUIDs and hot samples  

Energy Technology Data Exchange (ETDEWEB)

Low transition temperature (low-{Tc}) and high-{Tc} Superconducting QUantum Interference Devices (SQUIDs) have been used to perform high-resolution magnetic measurements on samples whose temperatures are much higher than the operating temperatures of the devices. Part 1 of this work focuses on measurements of the rigidity of flux vortices in high-{Tc} superconductors using two low-{Tc} SQUIDs, one on either side of a thermally-insulated sample. The correlation between the signals of the SQUIDs is a direct measure of the extent of correlation between the movements of opposite ends of vortices. These measurements were conducted under the previously-unexplored experimental conditions of nominally-zero applied magnetic field, such that vortex-vortex interactions were unimportant, and with zero external current. At specific temperatures, the authors observed highly-correlated noise sources, suggesting that ...

1997-05-01

231

The Application of High Resolution Sequence Stratigraphy for Understanding the Hydrocarbon Prospectivity of the Moere and Southern Voering Basins  

Energy Technology Data Exchange (ETDEWEB)

The deep water parts of the Moere and Southern Voering Basins are large frontier areas, which are considered to contain significant undiscovered hydrocarbon resources, within Cretaceous and Paleogene reservoirs. PGS Reservoir AS have evaluated the Cretaceous and Paleogene successions of the shallow and deep water areas offshore Mid-Norway using high-resolution sequence stratigraphic techniques. The successions have been subdivided into about 20 stratigraphic sequences. The results are: (1) A more acurate and higher resolution stratigraphy, (2) Greater constraints on basin palaeoenvironmental and palaeogeographic reconstructions, (4) Fully integrated sandstone fairway models, with increased ability to reservoir and seal quality and continuity, (5) In addition to several obvious giant domal traps, subtler yet significant structural and stratigraphic leads and prospects can be identified, (6) The timing, volume and phase of hydrocarbon generation ...

1999-07-01

232

Dynamics of polyethylene studied by high resolution neutron spectrometer LAM-80ET  

Energy Technology Data Exchange (ETDEWEB)

We have recently developed a high resolution quasielastic neutron scattering spectrometer LAM-80ET by applying mica crystals as analyzers and achieved a resolution of [Delta][epsilon] = 1.3 [mu]eV using the 002 reflection. Single chain dynamics of polyethylene has been investigated below and above the melting temperature T[sub m] (=135degC) to show the feasibility of the mica 002 reflection as the analyzer. It was found that elastic scattering intensity from polyethylene decreases very steeply around the T[sub m]. Quasielastic broadening in the spectrum at Q = 0.082 A[sup -1] is observed only above 210degC, which is 75degC higher than the T[sub m]. From the analysis of the spectra by a curve-fitting method, the width of the quasielastic component was evaluated to be 1.8 [mu]eV at 250degC and the activation energy of the width to be 34 kJ/mol. (author).

1992-06-01

233

Dynamics of polyethylene studied by high resolution neutron spectrometer LAM-80ET  

International Nuclear Information System (INIS)

We have recently developed a high resolution quasielastic neutron scattering spectrometer LAM-80ET by applying mica crystals as analyzers and achieved a resolution of #DELTA##epsilon# = 1.3 #mu#eV using the 002 reflection. Single chain dynamics of polyethylene has been investigated below and above the melting temperature T_m (=135degC) to show the feasibility of the mica 002 reflection as the analyzer. It was found that elastic scattering intensity from polyethylene decreases very steeply around the T_m. Quasielastic broadening in the spectrum at Q = 0.082 A"-"1 is observed only above 210degC, which is 75degC higher than the T_m. From the analysis of the spectra by a curve-fitting method, the width of the quasielastic component was evaluated to be 1.8 #mu#eV at 250degC and the activation energy of the width to be 34 kJ/mol. (author).

234

Shot-noise-limited measurement of sub-parts-per-trillion birefringence phase shift in a high-finesse cavity  

International Nuclear Information System (INIS)

We report on a promising approach to high-sensitivity anisotropy measurements using a high-finesse cavity locked by optical feedback to a diode laser. We provide a simple and effective way to decouple the weak anisotropy of interest from the inherent mirror's birefringence whose drift may be identified as the key limiting parameter in cavity-based techniques. We demonstrate a shot-noise-limited phase shift resolution previously inaccessible in an optical cavity, readily achieving the state-of-the-art level of 3x10"-"1"3 rad.

2010-09-01

235

''SEPIO NUANCE DT'' digital mammography system  

International Nuclear Information System (INIS)

In the past, the need for high quality images, i.e., very sharp and clear images, in mammography have prevented mammography equipment from being digitalized; however, recent advances in detection technology such as development of a high resolution digital X-ray detector have produced improvements in digital mammography. Digital mammography is expected to replace conventional film-screen mammography. We have developed a digital mammography system, named ''SEPIO NUANCE DT'', which is equipped with a direct conversion flat panel detector. The present paper describes the high basic performance and user-friendly functions of the system. (author)

2007-03-01

236

High performance polymer electrolyte fuel cells with ultra-low Pt loading electrodes prepared by dual ion-beam assisted deposition  

International Nuclear Information System (INIS)

Ultra-low pure Pt-based electrodes (0.04-0.12 mg_P_t/cm"2) were prepared by dual ion-beam assisted deposition (dual IBAD) method on the surface of a non-catalyzed gas diffusion layer (GDL) substrate. Film thicknesses ranged between 250 and 750 A, these are compared with a control, a conventional Pt/C (1.0 mg_P_t_(_M_E_A_)/cm"2, E-TEK). The IBAD electrode constituted a significantly different morphology, where low density Pt deposits (largely amorphous) were formed with varying depths of penetration into the gas diffusion layer, exhibiting a gradual change towards increasing crystalline character (from 250 to 750 A). Mass specific power density of 0.297 g_P_t/kW is reported with 250 A IBAD deposit (0.04 mg_P_t/cm"2 for a total MEA loading of 0.08 mg_P_t/cm"2) at 0.65 V. This is contrasted with the commercial MEA with a loading of 1 mg_P_t_(_M_E_A_)/cm"2 where mass specific power density obtained was 1.18 g_P_t/kW (at 0.65 V), a value typical of current state of the ...

2006-06-05

237

Investigation by XRF and XRD of Zn and Fe in Fe{sub x} Zn{sub 1-x} thin films  

Energy Technology Data Exchange (ETDEWEB)

Fe{sub x}Zn{sub 1-x} alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K{beta}/K{alpha} x-ray intensity ratios of Zn and Fe in Fe{sub x}Zn{sub 1-x} thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi {sup 241}Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in Fe{sub x}Zn{sub 1-x} thin films for different values of x. The reason for this ...

2008-12-15

238

Investigation by XRF and XRD of Zn and Fe in Fex Zn1-x thin films  

International Nuclear Information System (INIS)

FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason for this change may be that the electronegativity of iron is ...

2008-12-01

239

Transbrachial arterial digital subtraction angiography  

International Nuclear Information System (INIS)

27 cases including 7 outpatients, underwent intraarterial DSA using 4-F nylon catheter, by transbrachial arterial approach. Much of DSAs were performed in Fuji Computed Radiography (FCR), which has high spatial resolution. In all cases, image quality satisfied clinical demands. No major complication occured in this series. Transbrachial arterial digital subtraction angiography is excellent and safe method for screening of vascular disease. (author).

1985-01-01

240

Structural relaxation and crystallization in the Fe-Cr-Si-B and Fe-Cu-Cr-Si-B amorphous alloys  

International Nuclear Information System (INIS)

Structural relaxation, crystallization and optimisation processes in soft magnetic amorphous alloys based on iron are examined by applying different experimental techniques: X-ray diffraction analysis, high-resolution electron microscopy, measurements of magnetic and electric properties (permeability, after-effect resistivity). The presented results are discussed in terms of annealing out of microvoids, formation of nanocrystalline phase and changes of effective magnetostriction constant. (author)

2001-09-23

241

Si(111)/Gd: A fast and high-resolution thermal neutron detector  

Energy Technology Data Exchange (ETDEWEB)

Recent developments in design and production of thermal neutron detectors based on a crystalline Si diode coupled to a Gd converter are reviewed. The most significant results of neutron test measurements carried out on prototype systems and pointing out the performances of the device are reported. Progress through various detection schemes and technological solutions for the production of a real time neutron counter for routine operation are outlined.

1998-07-01

242

Research in heavy-ion nuclear physics. Annual progress report, May 1, 1991--April 30, 1992  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.

1992-01-01

243

Real time neutron diffraction experiments using Bragg edges  

Energy Technology Data Exchange (ETDEWEB)

Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.

1995-12-31

244

Real time neutron diffraction experiments using Bragg edges  

International Nuclear Information System (INIS)

Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.

1994-12-02

245

Proposed high-resolution vertex detector using superconductive thin strips  

Energy Technology Data Exchange (ETDEWEB)

The possibility of fabricating a superconductive vertex detector is discussed on the basis of a preliminary experiment. The experiment has shown that an indium strip 15 mm long, 20 ..mu..m wide and 0.1 ..mu..m thick is changed from the superconductive state to the normal state when struck by a single 5.4 MeV alpha particle.

1984-06-01

246

Proceedings of the workshop on high resolution computed microtomography (CMT)  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the workshop was to determine the status of the field, to define instrumental and computational requirements, and to establish minimum specifications required by possible users. The most important message sent by implementers was the remainder that CMT is a tool. It solves a wide spectrum of scientific problems and is complementary to other microscopy techniques, with certain important advantages that the other methods do not have. High-resolution CMT can be used non-invasively and non-destructively to study a variety of hierarchical three-dimensional microstructures, which in turn control body function. X-ray computed microtomography can also be used at the frontiers of physics, in the study of granular systems, for example. With high-resolution CMT, for example, three-dimensional pore geometries and topologies of soils and rocks can be obtained readily and implemented directly in transport models. In turn, these geometries can ...

1997-02-01

247

Pharmaceutics | Special Issue: Molecular Imaging  

Wastenet

...) Abstract: Fluorescence microscopic imaging is widely used in biomedical research to study molecular and cellular processes in cell culture or tissue samples. This is motivated by the high inherent sensitivity of fluorescence techniques, the spatial resolution that compares favorably with cellular dimensions, the stability of the fluorescent labels used and the sophisticated strategies that have been developed for selectively labeling target molecules. More recently, two and ...

248

Optimization of soft magnetic properties in Fe-B and Fe-B-Si amorphous alloys obtained by melt spinning method  

International Nuclear Information System (INIS)

In the present paper the progress of optimization of soft magnetic properties have been studied by applying different experimental techniques (magnetic measurements, electric measurements, X-ray analysis, and high-resolution electron microscopy observation). It has been shown that an increase in magnetic permeability after optimization annealing can be mainly attributed to annealing out of microvoids. (author)

2001-09-23

249

On the Metastable Level in Ni-like Ions  

Energy Technology Data Exchange (ETDEWEB)

The lowest excited level in Ni-like ions, 3d{sup 9}4s {sup 3}D{sub 3}, decays only via a magnetic octupole (M3) decay. They present calculated values of transition wavelengths and rates for ions with 30 {le} Z {le} 100. They have observed this line in Xe{sup 26+}, using the Livermore EBIT-I electron beam ion trap and a microcalorimeter, as well as a high-resolution flat-field grating spectrometer.

2004-09-14

250

Measurement of gas flow velocities by laser-induced gratings  

Energy Technology Data Exchange (ETDEWEB)

Time resolved light scattering from laser-induced electrostrictive gratings was used for the determination of flow velocities in air at room temperature. By measuring the velocity profile across the width of a slit nozzle we demonstrated the high spatial resolution (about 200 mm) of this novel technique. (author) 3 figs., 1 ref.

1999-08-01

251

Laser photochemical etching of molybdenum and tungsten thin films by surface halogenation  

Energy Technology Data Exchange (ETDEWEB)

Laser direct-write etching of the refractory metals Mo and W was developed using reactions in chlorine and nitrogen trifluoride vapors. Rate and high spatial resolution are simultaneously optimized using a two-vapor halogenation/development sequence, based on surface modification. Local-area laser chlorination of the metal surface is used to predispose areas to subsequent bulk etching.

1986-12-01

252

Investigation of morphology and chemical composition of self-organized semiconductor quantum dots and wires by X-ray scattering  

International Nuclear Information System (INIS)

X-ray scattering methods suitable for the investigation of the morphology and chemical composition of self-organized quantum dots and quantum wires are reviewed. Their application is demonstrated in experimental examples showing that a combination of small angle X-ray scattering with high-resolution X-ray diffraction can reveal both the shape and the chemical composition of the self-organized objects. (author)

2001-09-23

253

High resolution transmission electron microscopy of a #beta#'-sialon-TiN nanocomposite  

International Nuclear Information System (INIS)

TEM and HRTEM have been used to characterise the microstructures of materials formed by hot-pressing silicon nitride with an Al_2O_3-SiO_2-TiO_2 densification aid system, to form #beta#'-sialon-TiN composites in which the TiN particles are of 20-100 nm dimension. (orig.).

1992-06-21

254

Bragg-curve spectroscopy at high rates  

Energy Technology Data Exchange (ETDEWEB)

The performance of a Bragg ionization chamber has been investigated as a function of the counting rate with approx.= 5 MeV/amu /sup 32/S beams: up to approx.= 20 kHz the energy resolution is below 0.9% and the Z resolving power is more than 50. (orig.).

1986-03-01

255

Bounding ingestion stream-tube determination via a CO tracer  

Energy Technology Data Exchange (ETDEWEB)

A gas tracer technique based on carbon monoxide and a commercial automotive exhaust gas analyser has been applied to wind tunnel models of waterjet propulsion systems intakes. The post-processing and interpretation of the carbon monoxide concentration signals has yielded high resolution measurements of the bounding ingestion stream-tubes. (orig.) With 3 figs., 1 tab., 8 refs.

1998-05-01

256

An imaging. gamma. -ray detector with scatter rejection for beam position control in radiotherapy  

Energy Technology Data Exchange (ETDEWEB)

An imaging detector for {gamma}-rays ({approx equal}1 MeV) based on minicell MWPCs with converters and a position resolution of {Delta}x=0.5 mm has been developed and tested. Very high rate capability (>10{sup 8}/cm{sup 2} s) and a special readout for suppression of scattered radiation are implemented allowing to enhance the measured contrast. The relevant physical processes are discussed and first pictures are presented. (orig.).

1991-12-01

257

A photon beam position monitor for SSRL beamline 9  

Energy Technology Data Exchange (ETDEWEB)

We present here the concept of a simple one dimensional photon beam position monitor for use with high power synchrotron radiation beams. It has micron resolution, reasonable linearity in an inexpensive design. Most important, is its insensitivity to diffusely scattered low energy radiation from components upstream of the monitor.

1995-10-01

258

A 3D tomographic EBSD analysis of a CVD diamond thin film  

Energy Technology Data Exchange (ETDEWEB)

We have studied the nucleation and growth processes in a chemical vapor deposition (CVD) diamond film using a tomographic electron backscattering diffraction method (3D EBSD). The approach is based on the combination of a focused ion beam (FIB) unit for serial sectioning in conjunction with high-resolution EBSD. Individual diamond grains were investigated in 3-dimensions particularly with regard to the role of twinning.

2008-09-15

259

Weldability of high strength Ni-based alloy USC141 as boiler tube for 700 C USC plant  

Energy Technology Data Exchange (ETDEWEB)

Recently the increase of steam temperature and pressure of power plant is required to enhance the thermal efficiency and reduce the CO{sub 2} emission. For the application to advanced USC (Ultra Super Critical) boiler with steam temperature around 700 C, the application of Ni-based alloy such as Alloy617 will be necessary. A new Ni-based alloy USC141 (20Cr-10Mo-2Ti-Al-bal.Ni) with excellent creep rupture strength and low thermal expansion has been developed by Hitachi Ltd. and Hitachi Metals Ltd. as the candidate material for 700 C USC turbine components. In present work, to investigate the possibility for boiler tube application of USC141, its weldability and high temperature strength properties were experimentally examined. The tested material as solution-treated condition shows higher creep rupture strength than that of Alloy617. GTAW (Gas Tungsten Arc Welding) trials of tubular specimen using NIMONIC263 filler wire were conducted ...

2007-07-01

260

The Schenberg spherical antenna: status report  

International Nuclear Information System (INIS)

Full text. Here we present a status report of the Schenberg antenna, which started commissioning runs in September 2006 under the full support of FAPESP. In its first commissioning runs we tested three preliminary parametric transducer systems, which did not achieve a high enough performance for placing the antenna sensitivity in the range of the calibrator capacitor. Instead of improving the calibrator, making it capable of introducing a larger input force, we decided to go to a radical upgrading operation: replacing the three transducers for a complete set of six transducers, with better sensitivity and arranged according to the truncated icosahedron configuration, plus two extra ones; starting to install the dilution refrigerator; installing wires, cables, and amplifiers for the complete set of transducer circuits; and a new suspension and vibration isolation system for the cabling and microstrip antennas. We also have been developing a new set of transducers, ...

2009-09-14

261

Review of Central Research Institute of Electric Power Industry. Coal utilization technology harmonious with the environment. Kankyou ni yasashii sekitann riyo gijyutu. Kankyo ni yasashii sekitan riyo gijutsu  

Energy Technology Data Exchange (ETDEWEB)

Studies are made on coal in terms of its effective utilization, coal cleaning, fluidization and production of new fuel, and issues globally raised. Coal is abundant in reserves and high in supply stability and economic efficiency. However, it is much in CO2 emission per calorific value. To control as much CO2 emission as possible, effective utilization such as increasing of power generation efficiency has been proceeded with. In addition to ultra supercritical pressure and fluidized bed combustion, cited are coal gasification combined cycle power generation and high temperature type fuel cell. Coal has 5-20% ash and impurities like sulfur/nitrogen. Coal should be used clean by pollution abatement measures such as dust collecting, desulfurization and denitrification. Japan is at a world top level of these technologies. Coal is solid, and therefore, is more difficult to handle than liquid fuel. To use it easily, coal is ...

1994-04-25

262

Production of ultra high strength steels by turbulent water cooling equipment (TWICE); Production d'aciers haute resistance par un dispositif de refroidissement a turbulence controlee  

Energy Technology Data Exchange (ETDEWEB)

A new industrial process allowing to reach very high cooling rates in the cooling section after soaking of a continuous annealing line for steel sheets is presented. This process constitutes the successful conclusion of a long term research programme, jointly carried out at CRM and Arcelor Cockerill-Sambre for three years, including laboratory experiments, pilot scale trials and several industrial campaigns. It is running on from developments performed in the framework of the HOWAQ (Hot Water Quench) process. The process successively combines a moderate cooling step (600 deg C/s for 0.8 mm thick strips), in boiling water, and a faster cooling step (above 700 deg C/s), by impinging turbulent cold water in a box. Its main features are simplicity, resulting from advanced developments, soundness, flexibility and cooling homogeneity. As treated steel products are characterized by improved mechanical properties, outstanding surface quality (corrosion resistance) and ...

2003-08-01

263

Potentials of biofuels  

Energy Technology Data Exchange (ETDEWEB)

This paper discussed the potential of biofuels with particular reference to the situation in Germany and Europe. Emphasis was on technical potential, such as biofuel production, utilization and environmental aspects. The Institute of Agricultural Technology and Biosystems Engineering ran vTI emission tests on diesel engines to evaluate the environmental impacts of biofuels. This testing facility is able to drive heavy-duty diesel engines in both stationary and dynamic test cycles, such as the European ESC and ETC. Additional analyses were conducted to determine the fine and ultra-fine particles, polycyclic aromatic hydrocarbons (PAH), aldehydes, ketones, and the usual regulated exhaust gas compounds. Ames tests were conducted to assess the mutagenic potential of tailpipe emissions. Previous study results showed that neat vegetable oils can render the exhaust high in mutagenic potency. Some of the non-regulated exhaust gas compounds were found ...

2010-07-01

264

Fiscal 1997 report of the R and D result of industrial science and technology. R and D on synergy ceramics (development of rational energy use technology); 1997 nendo sangyo kagaku gijutsu kenkyu kaihatsu seika hokokusho. Synergy ceramics no kenkyu kaihatsu (energy shiyo gorika gijutsu kaihatsu)  

Energy Technology Data Exchange (ETDEWEB)

For rational use of energy resources, the process technology which allows harmonization and multiplication of conflicting characteristics was developed for development of new ceramic system materials. This paper summarizes the result in fiscal 1997. On a structural reaction process among creation technologies of ultra-reliable structure, study was made on structure control and hot-working technology through atmosphere control in ceramics synthesis. On basic technology for analysis and evaluation, study was made on the effect of particle bridging on strengthening and toughening of ceramic materials. Study was also made on a toughness expression mechanism, FEM model analysis of particle bridging, and crack growth resistance of ceramics. On control of solid solution precipitation, new alumina ceramics with high strength, hardness and wear resistance was obtained by transgranularly precipitating nano-size particles from a fine-grain ...

1998-03-01

265

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

266

Performance of a Bragg curve detector for heavy ion identification  

Energy Technology Data Exchange (ETDEWEB)

By using Bragg curve spectroscopy, one can measure atomic number and energy of high energy heavy ions stopping in a gas-filled ionization chamber with longitudinal electric field. In this paper, we report on the results obtained with an isobutane filled detector. An energy resolution of 0.8% fwhm and a Z resolution of 2.7% fwhm were achieved for elastically scattered 300 MeV /sup 40/Ar ions. We study the Bragg peak amplitude dependence on the energy of the incoming ions, a dependence presumably due to the Frisch grid screening inefficiency. The corrected Bragg peak spectrum of inelastically scattered 300 MeV /sup 40/Ar ions exhibits a satisfactory Z separation around Z = 18.

1982-12-15

267

Performance of a Bragg curve detector for heavy ion identification  

International Nuclear Information System (INIS)

By using Bragg curve spectroscopy, one can measure atomic number and energy of high energy heavy ions stopping in a gas-filled ionization chamber with longitudinal electric field. In this paper, we report on the results obtained with an isobutane filled detector. An energy resolution of 0.8% fwhm and a Z resolution of 2.7% fwhm were achieved for elastically scattered 300 MeV "4"0Ar ions. We study the Bragg peak amplitude dependence on the energy of the incoming ions, a dependence presumably due to the Frisch grid screening inefficiency. The corrected Bragg peak spectrum of inelastically scattered 300 MeV "4"0Ar ions exhibits a satisfactory Z separation around Z = 18. (orig.).

268

Particle and X-ray damage in pn-CCDs  

Energy Technology Data Exchange (ETDEWEB)

The fully depleted pn-junction charge coupled device (pn-CCD) has been developed as a detector for X-ray imaging and high-resolution spectroscopy for the X-ray satellite missions XMM and ABRIXAS. If the detector is exposed to a particle radiation environment, the energy resolution is degraded due to charge transfer losses and a dark current increase. In a first experiment, prototype devices were irradiated with 10 MeV protons. After completion of the detector development, the proton irradiation was repeated for a quantitative study of the radiation damage, relevant for the satellite missions. The irradiation test was extended by a 5.5 MeV {alpha}-particle and a 6 keV X-ray exposure of the pn-CCD, including the CAMEX preamplifier chip.

2000-01-11

269

Focused ion beam fabrication and properties of nanoscale Josephson junctions for sensors and other applications  

International Nuclear Information System (INIS)

The methods of superconducting device fabrication by lithography and multilevel processing usually require a number of processing steps with lithographic resolution and alignment adequate for the scale of the device be fabricated. As an alternative, the focused ion beam (FIB) microscope is increasingly being used directly to fabricate devices. A major advantage of using a FIB compared to other lithography methods is its flexibility and high resolution. It allows in-situ, milling (#propor to#5 nm at a beam current of 1 pA) to a variety of depths, and imaging (2 nm) of the sample. In this paper we describe our development of junction fabrication techniques using the FIB and their application in creating a range of potential sensor devices and quantum electronics applications. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2005-03-01

270

Absolute differential cross sections for electron capture and loss by kilo-electron-volt hydrogen atoms  

International Nuclear Information System (INIS)

This paper reports measurements of absolute differential cross sections for electron capture and loss for fast hydrogen atoms incident on H_2, N_2, O_2, Ar, and He. Cross sections have been determined in the 2.0- to 5.0-keV energy range over the laboratory angular range 0.02 degree--2 degree, with an angular resolution of 0.02 degree. The high angular resolution allows us to observe structure at small angles in some of the cross sections. Comparison of the present results with those of other authors generally shows very good agreement.

271

A method for determining the origin of bitumoids  

Energy Technology Data Exchange (ETDEWEB)

The invention is associated with organic geochemistry and may be used in conducting geological exploration operations for oil and gas. The purpose of the invention is to increase the precision of the method for determining the genesis of bitumoids. This is achieved through determining the isotopic composition of nickel or vanadium and from the anomalously high values of the isotopic ratio of Ni-58 to Ni-62 or from the anomalously low values of the isotopic ratio of vanadium, a conclusion is drawn about the epigenetic nature of the bitumoids. The proposed method is characterized by greater resolution due to the fact that the values of the isotopic ratios for oil bearing and water bearing structures are essentially not superimposed. The proposed method exceeds the resolution of metal metering studies in conducting geological exploration for oil and gas by 2 to 3 times.

1983-01-01

272

A fast multipole transformation for global climate calculations  

Energy Technology Data Exchange (ETDEWEB)

A fast multipole transformation is adapted to the evaluation of summations that occur in global climate calculations when transforming between spatial and spherical harmonic representations. For each summation, the timing of the fast multipole transformation scales linearly with the number of latitude gridpoints, but the timing for direct evaluations scales quadratically. In spite of a larger computational overhead, this scaling advantage renders the fast multipole method faster than direct evaluation for transformations involving greater than approximately 300 to 500 gridpoints. Convergence of the fast multipole transformation is accurate to machine precision. As the resolution in global climate calculations continues to increase, an increasingly large fraction of the computational work involves the transformation between spatial and spherical harmonic representations. The fast multipole transformation offers a significant reduction in computational time for these ...

1996-01-01

273

Comparison of high resolution whole-body MRI using parallel imaging and PET-CT. First experiences with a 32-channel MRI system  

International Nuclear Information System (INIS)

To compare the accuracy in the detection and staging of various malignant tumors with high resolution whole-body MRI using parallel imaging with whole-body dual-modality PET-CT. Preliminary results of an interim analysis from a prospective, blinded study are presented, in which 20 patients (mean age 59 years, range 27-77 years) with different oncological diseases underwent whole-body dual modality FDG-PET-CT screening for tumor search or staging in case of confirmed or suspected metastatic disease. All patients also underwent whole-body MRI imaging with the use of parallel imaging (iPAT). High-resolution coronal T1w- and STIR-sequences of 5 body levels with 512 x 512 matrix, axial fast T2w imaging of lung and abdomen (HASTE), contrast-enhanced dynamic and static T1w-sequences of liver, brain, abdomen, and pelvis were performed. Using a 32-channel whole-body MRI scanner (Magnetom Avanto, Siemens Medical Solutions) with a ...

274

High resolution electron microscopy and computer simulation studies of the atomic structure of tilt boundaries in TiO{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

The atomic structure of [001] tilt grain boundaries of {Sigma}5 (210), {Sigma}5 (310), {Sigma}13 (320) and {Sigma}17 (410) in TiO{sub 2}(rutile) were studied using high resolution electron microscopy and computer simulation. Regularly separated small steps (1/2 [120] high) and big steps (3/2 [120] high) which contain secondary dislocations were found in the (210) boundary as a result of deviation from the exact {Sigma}5 misorientation and (210) symmetric plane. Similar steps were also found in (310) and (320) boundaries. Flat segments between the steps were found to have very accurate misorientation of the {sigma}`s and a nearly symmetric boundary plane. Their rigid body translation, volume expansion and relaxed structures were determined by comparing HRTEM images with computer calculated structures and simulated images. An irregular core structure was found in the (410) boundary when its misorientation ...

1995-09-01

275

Experimental Evaluation And Simulation Of Multi-pixel Cadmium-zinc-telluride Hard-x-ray Detectors  

CERN Document Server

This dissertation describes the evaluation of many-pixel Cadmium-Zinc-Telluride (CdZnTe) hard-X-ray detectors for future use with the High Energy Replicated Optics (HERO) telescope being developed at Marshall Space Flight Center. The detector requirements for the HERO application are good energy resolution (sufficient to resolve cyclotron features and nuclear lines), spatial resolution of ∼200 μm, minimal charge loss of absorbed X rays, and minimal sensitivity to the background environment. This research concentrates on assessing the suitability of these detectors for the focus of HERO, and includes the development of a simulation of the physics involved in an X-ray-detector interaction, a study of the intrinsic material properties, measurements with prototype detectors such as the energy and spatial resolution, charge loss, and X-ray background reduction through 3-dimensional depth ...

2004-01-01

276

Digital direct magnification mammography with storage phosphor screens. Standardized and image result dependent post-processing parameters  

International Nuclear Information System (INIS)

Present day mammography has not been able to make use of the advantages of digital luminescence radiography because of the limited spatial resolution. The recent development of electromagnetic focusing X-ray tube with effective focal spot sizes from 0.04 to 0.12 mm allows radiographic direct magnification with less geometric blur. It is now possible to combine direct magnification mammography with digital luminescence radiography. By combining high quality storage phosphor screens with an HQ-workstation a spatial resolution of 8 lp/mm is possible for 1.7-fold magnification. For 4-fold spot magnification views spatial resolution can be theoretically increased to approx. 20 lp/mm. One important advantage of digital radiography is the possibility of image-postprocessing. This article presents two sets of standard parameters and three sets of image dependent parameters for better imaging of specific ...

277

The AMS-02 electromagnetic calorimeter  

CERN Document Server

The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).

2002-01-01

278

Study of radiation chemistry in solids using solid hydrogen  

Energy Technology Data Exchange (ETDEWEB)

Having simple and highly symmetric structure, solid hydrogen is a useful matrix on the study of radiation-chemical processes in solid phase which have been less understood in previous studies. We have found three outstanding findings: resonance effects on the tunneling reaction H+H{sub 2} {yields} H{sub 2} + H, effects of pressure on the dissociation and recombination of H{sub 2} molecules in solid hydrogen, and high-resolution ESR spectroscopy using a solid parahydrogen matrix. (author)

2002-03-01

279

Randomization of heavily damaged regions in annealed low energy Ge{sup +}-implanted (0 0 1)Si  

Energy Technology Data Exchange (ETDEWEB)

Apparent growth of amorphous layers during low temperature annealing was observed in low energy Ge{sup +}-implanted (0 0 1)Si by high-resolution transmission electron microscopy. The occurrence of abnormal growth is due to the randomization of heavily damaged regions beneath the original amorphous/crystalline interfaces. The randomization process is attributed to the strain, incurred by the presence of a high density of large Ge atoms in the heavily damaged Si substrate, relaxation to lower the free energy of the systems. The randomization upon annealing may be fruitfully applied to minimize the transient enhanced diffusion in shallow junction formation.

2004-01-15

280

Randomization of heavily damaged regions in annealed low energy Ge"+-implanted (0 0 1)Si  

International Nuclear Information System (INIS)

Apparent growth of amorphous layers during low temperature annealing was observed in low energy Ge"+-implanted (0 0 1)Si by high-resolution transmission electron microscopy. The occurrence of abnormal growth is due to the randomization of heavily damaged regions beneath the original amorphous/crystalline interfaces. The randomization process is attributed to the strain, incurred by the presence of a high density of large Ge atoms in the heavily damaged Si substrate, relaxation to lower the free energy of the systems. The randomization upon annealing may be fruitfully applied to minimize the transient enhanced diffusion in shallow junction formation.

2004-01-01

281

K_#beta#/K_#alpha# X-ray intensity ratio following K-electron capture and radioisotope excitation  

International Nuclear Information System (INIS)

The K_#beta#/K_#alpha# X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49<=Z<=82 following electron capture decay and photon excitation using "2"4"1Am and "5"7Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K_#beta#/K_#alpha# values on the mode of excitation in the case of Mn and Fe is attribuited to the chemical effects, while no such dependence is found for the high-Z elements.

1987-01-01

282

Electron impact ionization of C_6_0 and C_7_0 and decay of the singly and multiply charged (up to z=7) ions produced  

International Nuclear Information System (INIS)

Mass spectrometry was instrumental in the discovery of the fullerenes and the characterization of their special structure (truncated icosahedron). High resolution and high sensitivity mass spectrometry in combination with a crossed molecular beam/electron beam ion source is used here to study a further, very unique property of singly and multiply charged fullerene ions (up to Z=7), i.e. their strong resilience towards decomposition via sequential C_2 evaporation and via Coulomb explosion, respectively. (author).

1994-03-20

283

REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.  

Energy Technology Data Exchange (ETDEWEB)

Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are ...

1999-05-01

284

Endoluminal ultrasound applicator with an integrated RF coil for high-resolution magnetic resonance imaging-guided high-intensity contact ultrasound thermotherapy  

International Nuclear Information System (INIS)

High-intensity contact ultrasound (HICU) under MRI guidance may provide minimally invasive treatment of endocavitary digestive tumors in the esophagus, colon or rectum. In this study, a miniature receive-only coil was integrated into an endoscopic ultrasound applicator to offer high-resolution MRI guidance of thermotherapy. A cylindrical plastic support with an incorporated single element flat transducer (9.45 MHz, water cooling tip) was made and equipped with a rectangular RF loop coil surrounding the active element. The integrated coil provided significantly higher sensitivity than a four-element extracorporeal phased array coil, and the standard deviation of the MR thermometry (SDT) improved up to a factor of 7 at 10 mm depth in tissue. High-resolution morphological images (T1w-TFE and IR-T1w-TSE with a voxel size of 0.25 x 0.25 x 3 mm3) and accurate thermometry data (the PRFS method with a voxel size of 0.5 x 0.5 x 5 ...

2008-11-21

285

Using Gamma-Ray Burst Prompt Emission to Probe Relativistic Shock Acceleration  

CERN Document Server

It is widely accepted that the prompt transient signal in the 10 keV - 10 GeV band from gamma-ray bursts (GRBs) arises from multiple shocks internal to the ultra-relativistic expansion. The detailed understanding of the dissipation and accompanying acceleration at these shocks is a currently topical subject. This paper explores the relationship between GRB prompt emission spectra and the electron (or ion) acceleration properties at the relativistic shocks that pertain to GRB models. The focus is on the array of possible high-energy power-law indices in accelerated populations, highlighting how spectra above 1 MeV can probe the field obliquity in GRB internal shocks, and the character of hydromagnetic turbulence in their environs. It is emphasized that diffusive shock acceleration theory generates no canonical spectrum at relativistic MHD discontinuities. This diversity is commensurate with the significant range of spectral indices discerned in ...

2010-01-01

286

Ultra-high tritium decontamination of simulated fusion fuel exhaust using a 2-stage palladium membrane reactor  

Energy Technology Data Exchange (ETDEWEB)

A 2-stage cold (non-tritium) PMR system was tested with the ITER mix in61 days of continuous operation. No decrease in performance was observed over the duration of the test. Decontamination factor (DF) was found to increase with decreasing inlet rate. Decontamination factors in excess of 1.4 {times} 10{sup 5} were obtained, but the exact value of the highest DF could not be determined because of analysis limitations. Results of the 61-day test were used to design a 2-stage PMR system for use in tritium testing. The PMR system was scaled up by a factor of 6 and built into a glovebox in the Tritium Systems Test Assembly (TSTA) of the Los Alamos National Laboratory. This system is approximately 1/5th of the expected full ITER scale. The ITER mix was injected into the PMR system for 31 hours, during which 4.5 g of tritium were processed. The 1st stage had DF = 200 and the 2nd stage had DF = 2.9 {times} 10{sup 6}. The overall DF = 5.8 {times} 10{sup 8}, which is greater than ITER ...

1996-12-31

287

Ultra-high tritium decontamination of simulated fusion fuel exhaust using a 2-stage palladium membrane reactor  

International Nuclear Information System (INIS)

A 2-stage cold (non-tritium) PMR system was tested with the ITER mix in 61 days of continuous operation. No decrease in performance was observed over the duration of the test. Decontamination factor (DF) was found to increase with decreasing inlet rate. Decontamination factors in excess of 1.4x10"5 were obtained, but the exact value of the highest DF could not be determined because of analysis limitations. Results of the 61-day test were used to design a 2-stage PMR system for use in tritium testing. The PMR system was scaled up by a factor of 6 and built into a glovebox in the Tritium Systems Test Assembly (TSTA) of the Los Alamos National Laboratory. This system is approximately 1/5"t"h of the expected full ITER scale. The ITER mix was injected into the PMR system for 31 hours, during which 4.5 g of tritium were processed. The 1"s"t stage had DF =200 and the 2"n"d stage had DF=2.9x10"6. The overall DF=5.8x10"8, which is greater than ITER requirements. 3 refs., 10 figs.

1996-06-16

288

Research on deformation characteristic of AZ31Mg alloy and its constitutive equations  

Energy Technology Data Exchange (ETDEWEB)

Superplasticity of polycrystalline metallic materials is a phenomenon which shows hundreds to thousands of percents of large plastic deformation without necking in a steady state of low stress, when the uni-axial tensile loading is done in some special thermo-mechanical conditions (some limited ranges of properly high temperature and low strain rate). The main mechanism of superplastic phenomenon is the grain boundary sliding, while the main mechanism of usual plastic deformation is the trans-granular sliding. In this research, the possibility of superplastic deformation in a magnesium alloy (AZ31Mg alloy) was experimentally investigated, because generally speaking, the magnesium alloy whose atomic structure is hexagonal does not have enough formability in a form of trans-granular sliding mechanism. In this paper, the detail of experimental results are shown and discussed. Moreover, the constitutive equations of Mg alloy are proposed on the basis of the ...

2004-07-01

289

Optimization of advanced PMOS junctions using Ge, B and F co-implants  

International Nuclear Information System (INIS)

The main challenges for PMOS ultra shallow junction formation remain the transient enhanced diffusion (TED) and the solid solubility limit of boron in silicon. It has been demonstrated that low energy boron implantation and spike annealing are key in meeting the 90nm technology node ITRS requirements. To meet the 65nm technology requirements many studies have used fluorine co-implantation with boron and Si"+ or Ge"+ pre-amorphization (PAI) and spike annealing. Although using BF_2"+ can be attractive for its high throughput, self-amorphization and the presence of fluorine, many studies have shown that the fluorine successfully reduce TED, its energy needs to be well optimized with respect to the boron's, therefore BF_2"+ does not present the right fluorine/boron energy ratio for the optimum junction formation. In this work we optimize the fluorine energy for boron energies down to 200eV. We show the dependence of optimized junction on Ge"+ ...

2005-08-01

290

Monitoring power plant fireside corrosion using corrosion probes  

Energy Technology Data Exchange (ETDEWEB)

The ability to monitor the corrosion degradation of key components in fossil fuel power plants is of utmost importance for Futuregen and ultra-supercritical power plants. Fireside corrosion occurs in the high temperature sections of energy production facilities due to a number of factors: ash deposition, coal composition, thermal gradients, and low NOx conditions, among others. Problems occur when equipment designed for either oxidizing or reducing conditions is exposed to alternating oxidizing and reducing conditions. This can happen especially near the burners. The use of low NOx burners is becoming more commonplace and can produce reducing environments that accelerate corrosion. One method of addressing corrosion of these surfaces is the use of corrosion probes to monitor when process changes cause corrosive conditions. In such a case, corrosion rate could become a process control variable that directs the operation of a coal combustion or ...

2005-01-01

291

Mechanism of ageing in irradiated polymers  

Energy Technology Data Exchange (ETDEWEB)

Samples of ultra-high molecular weight polyethylene (UHMWPE) and nylon 66, of grades suitable for use in medical prostheses, were subjected to irradiation using a /sup 60/Co source. The effects of a 10 Mrad dose on percentage crystallinity, tensile behaviour and dynamic mechanical response were established 3 days after irradiation at intervals over a one year period. Crystallinity in UHMWPE was found to increase progressively during this period with consequent changes in mechanical behaviour. It is proposed that the observed ageing process arises from the breakdown of metastable groups in the polymer, which are formed on irradiation, with consequent release of long inter-lamella tie chains. This removes an inhibition to crystal perfection processes, which can occur at room temperature in polyethylene. Infra-red spectroscopic evidence supports the proposal that the metastable species is peroxy or hydroperoxy and that this decomposes on ageing to a carbonyl group, ...

1988-01-01

292

Mechanical properties of Fe -10Ni -7Mn martensitic steel subjected to severe plastic deformation via cold rolling and wire drawing  

Energy Technology Data Exchange (ETDEWEB)

Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was {epsilon} {approx}7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.

2010-07-01

293

Mechanical properties of Fe -10Ni -7Mn martensitic steel subjected to severe plastic deformation via cold rolling and wire drawing  

International Nuclear Information System (INIS)

Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was #epsilon# #approx#7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.

2010-07-01

294

Lyman-alpha emitters as tracers of the transitioning Universe  

CERN Document Server

Of the many ways of detecting high redshift galaxies, the selection of objects due to their redshifted Ly-alpha emission has become one of the most successful. But what types of galaxies are selected in this way? Until recently, Ly-alpha emitters were understood to be small star-forming galaxies, possible building-blocks of larger galaxies. But with increased number of observations of Ly-alpha emitters at lower redshifts, a new picture emerges. Ly-alpha emitters display strong evolution in their properties from higher to lower redshift. It has previously been shown that the fraction of ultra-luminous infrared galaxies (ULIRGs) among the Ly-alpha emitters increases dramatically between redshift three and two. Here, the fraction of AGN among the LAEs is shown to follow a similar evolutionary path. We argue that Ly-alpha emitters are not a homogeneous class of objects, and that the objects selected with this method reflect the general star forming ...

2011-01-01

295

Iridium and PGE in sedimentary rocks; Iridium et platinoides dans les roches sedimentaires  

Energy Technology Data Exchange (ETDEWEB)

The detection limit of Instrumental Neutron Activation Analysis (INAA), about a few microgram per kg, is not sufficient to determine iridium concentrations in most geological samples. Use of the coincidence counting of the 316 and 468 keV gamma-rays emitted during the decay of {sup 192}Ir, improved the sensitivity (0.01 microgram per kg). The high iridium content of the clay layers from the Cretaceous-Tertiary transition (KTB) has been considered as an evidence of the extra-terrestrial origin of the KTB mass extinction. However some results indicate that a significant part of the iridium content in sediments has a volcanic origin. Radiochemical Neutron Activation Analysis (RNAA) in some KTB samples and in basic and ultra-basic rocks show that, unlike in volcanic products, no PGE (platinoids) fractionation appears in KTB samples. The nearby chondritic PGE pattern supports an extra-terrestrial origin for the KTB iridium anomaly. 2 figs., 2 tabs., ...

1994-12-31

296

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO_2 films  

International Nuclear Information System (INIS)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...

297

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO[sub 2] films  

Energy Technology Data Exchange (ETDEWEB)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...

1993-07-16

298

High temperature aluminum electrolytic capacitors for ULEV inverters  

Energy Technology Data Exchange (ETDEWEB)

A comparison between the concepts of the hybrid electric vehicle (HEV) and the ultra low emission vehicle (ULEV) was presented. The ULEV uses a much larger engine compared to the HEV, but it uses a lower Kw generator/motor and inverter/charger to use the latest engine and battery technology. The underlying goal of the ULEV is to supply auxiliary power under start-up and heavy load conditions and to remove indirect systems such as steering, starting and blower control from the engine via small electric drives. The challenge is to build a ULEV that is robust enough to withstand any environmental conditions. Since the ULEV engine is larger, it can experience compartment temperatures greater than 125 degrees C, which limits the use of conventional filter capacitors. Nippon Chemi-Con has recently developed U787D, the world's first continuous 150 degrees C rated aluminum electrolytic capacitor designed to meet the ambient, ripple currents and vibration ...

2000-07-01

299

High performance ultra-steels with recyclable design  

Energy Technology Data Exchange (ETDEWEB)

The global production of steel is predicted to increase rapidly to meet future demands. In order to conserve the natural resources, certain measures must be taken. These include perfecting the recycling of steel, improving the performance to extend the life of the material, and reduce the need for massive production of steel by increasing the strength of the material. This paper presented a design concept for ultrafine complex microstructure steel. The National Research Institute for Metals in Japan has worked on a project which investigated 800 MPa ferrite steel for welded structures with a chemical composition similar to 400 MPa-class plain carbon steel. The doubled strength was attributed to grain refinement. Novel welding techniques were also used for joining the ultrafine microstructure. In this study, low carbon Si-Mn ferrite-pearlite steels were subjected to a thermo-mechanical treatment to produce a microstructure of 1 micron order ultrafine grain ferrite plus finely dispersed ...

2000-07-01

300

Hard, infrared black coating with very low outgassing  

Energy Technology Data Exchange (ETDEWEB)

Infrared astronomical instruments require absorptive coatings on internal surfaces to trap scattered and stray photons. This is typically accomplished with any one of a number of black paints. Although inexpensive and simple to apply, paint has several disadvantages. Painted surfaces can be fragile, prone to shedding particles, and difficult to clean. Most importantly, the vacuum performance is poor. Recently a plasma enhanced chemical vapor deposition (PECVD) process was developed to apply thick (30 {micro}m) diamond-like carbon (DLC) based protective coatings to the interior of oil pipelines. These DLC coatings show much promise as an infrared black for an ultra high vacuum environment. The coatings are very robust with excellent cryogenic adhesion. Their total infrared reflectivity of < 10% at normal incidence approaches that of black paints. We measured outgas rates of <10{sup -12} Torr liter/sec cm{sup 2}, comparable to bare ...

2008-06-02

301

Future limits on isotropic Lorentz violation in the photon sector from UHECRs and TeV gamma rays  

CERN Document Server

Present and future ultra-high-energy-cosmic-ray facilities (e.g., the Pierre Auger Observatory with South and North components) and TeV-gamma-ray telescope arrays (e.g., HESS/VERITAS and CTA) have the potential to set stringent indirect bounds on the nine Lorentz-violating parameters of nonbirefringent modified Maxwell theory minimally coupled to standard Dirac theory. Theoretically, the most interesting case is isotropic Lorentz violation, which is described by a single parameter [taken to vanish for the case of the standard Lorentz-invariant theory]. It appears possible to obtain in the future an upper (lower) indirect bound on this single isotropic Lorentz-violating parameter at the +10^{-21} (-10^{-17}) level. Comparison is made with existing and future direct bounds from laboratory experiments. The possible physics implications of upper bounds at the 10^{-21} level are also briefly discussed.

2011-01-01

302

First plasma experiment on spherical tokamak device UTST  

International Nuclear Information System (INIS)

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

2009-04-01

303

FIB implantation induced site-selectively grown self-assembled InAs QDs in a light emitting #mu#-diode  

International Nuclear Information System (INIS)

We present an approach for fabrication of intentionally positioned epitaxial InAs QDs in a micron sized light emitting diode. For site-selective growth, a combination of molecular beam epitaxy (MBE) and focused ion beam (FIB) implantation technology in an all-ultra-high-vacuum (UHV) setup has been employed. Single dot occupancy of almost 55 % on FIB patterned nano-depressions was successfully achieved. Thereafter, carrier injection and subsequent radiative recombination from the positioned InAs/GaAs self-assembled QDs was investigated by embedding these QDs in the intrinsic part of a GaAs-based micron sized p-i-n junction device. Few or single dot are expected to be electrically addressed in these devices. We report results from electroluminescence (EL) measurement which proves the single dot characteristics of our device. The EL spectra consist of sharp emission lines and their dependence on injection current shows linear behavior for exciton and quadratic ...

2010-03-21

304

Autosolvent effect of bitumen in thermal cracking; Netsubunkai hanno ni okeru bitumen no jiko yobai koka  

Energy Technology Data Exchange (ETDEWEB)

Tar sand bitumen is petroleum-based ultra-heavy oil, and has a great amount of reserve like coal. However, there are still a lot of problems for its highly effective utilization. This paper discusses whether the light components in bitumen show independent behavior during the thermal cracking of heavy components, or not. Solvent effect and reaction mechanism during the thermal cracking are also derived from the change of their chemical structures. Athabasca tar sand bitumen was separated into light and heavy fractions by vacuum distillation based on D-1660 of ASTM. Mixtures of the both fractions at various ratios were used as samples. Negative effect of the light fraction on cracking of the heavy fraction was observed with dealkylation and paraffin formation Polymerization of the dealkylated light fraction to the heavy fraction was suggested due to lack of hydrogen in the thermal cracking under nitrogen atmosphere, which resulted in the ...

1996-10-28

305

Development of high-field STM for 18 T cryocooled superconducting magnet  

International Nuclear Information System (INIS)

To study the nanoscale electronic order in strongly correlated electron systems and vortex states in high-Tc superconductors in high magnetic fields, we have developed scanning tunneling microscopy (STM) for the 18 T cryocooled superconducting magnet (18T-CSM). The test results of the STM operation in the 18T-CSM at room temperature indicate that our STM has a good atomic resolution up to 18 T when we use the nonmagnetic vibration-isolation table which reduce the vibration noise from the cryocoolers of the 18T-CSM. In this paper, we report on the design of the high-field STM system for large-scale magnets and its performance.

2009-02-01

306

A high sensitivity two-color interferometer for pulsed power plasmas  

International Nuclear Information System (INIS)

A high sensitivity, high bandwidth, two-color interferometer (1064 and 532 nm) has been tested on the Hawk pulsed power generator at the Naval Research Laboratory. The phase resolution is 10"-"5 waves with a rise time of 3 ns, a new capability for diagnosing plasmas, and neutrals in pulsed power experiments. The two-color feature is used to distinguish phase shifts from free (plasma) electrons and bound (neutral and ion) electrons. Simultaneous electron and neutral density measurements were demonstrated in a plasma opening switch (POS) experiment. The ability to measure small phase shifts with fast rise time were demonstrated in a plasma filled diode experiment. The high sensitivity and vibration isolation enable neutral gas distribution measurements from supersonic nozzles used in plasma radiation source experiments. Examples of these measurements and future applications are described. copyright 1997 ...

307

Imaging properties of the Medipix2 system exploiting single and dual energy thresholds  

CERN Document Server

Low noise, high resolution and high dose efficiency are the common requirements for most X-ray imaging applications. Especially in medical applications the dose efficiency is a necessity for detector systems. We present the imaging performance of the Medipix2 readout chip bump bonded to a 300 mu m thick Si detector as a function of the detection threshold, a free parameter not available in conventional integrating imaging systems. Spatial resolution has been measured using the modulation transfer function (MTF) and it varies between 8.2 Ip/mm and 11.0 Ip/mm at 70%. An associated measurement of noise power spectrum (NPS) permits us to derive the detective quantum efficiency (DQE) which can be as a high as 25.5 % for a broadband incoming spectrum. The influence of charge diffusion in the sensor together with threshold variation in the readout chip is discussed. Although the Medipix2 ...

2006-01-01

308

High resolution sequence stratigraphy, sedimentology, petrology and reservoir potentials of the Glauconitic member in Westerose and adjacent fields, Alberta, Canada  

Energy Technology Data Exchange (ETDEWEB)

This thesis studied the petrology and sequence stratigraphy of the Hoadley barrier, a Glauconitic member in the Westerose field in Alberta. The unit contains gas reserves in an extensive northeast-southwest trending marine complex. A high resolution sequence stratigraphic model was used to understand the facies development of the unit and the diagenetic pathway of the strata. Six high frequency sequences were identified within the Glauconitic member. Each are separated from one another by surfaces of incision or subaerial exposure which sometimes coincide with a flooding surface and erosion. This thesis provided a petrographic characterization and depositional history of each of the 6 sequences. Reservoir quality is developed within the relatively quartz-rich foreshore facies of the G2B sandstones. The G3 chert litharenite to sublitharenite sandstones are excellent gas producers because of their coarser grain size and ...

2002-07-01

309

4D experience on Girassol Field block 17, Angola  

Energy Technology Data Exchange (ETDEWEB)

The Girassol field is located in Angolan deep water of Block 17 and consists of large vertically stacked turbidities complexes. The reservoir extends over approximately 200 km{sup 2} and water depth ranges between 1300 and 1400 meters. In that context High Resolution 3D seismic became the most valuable tool to describe and monitor the reservoir. The field development plan took into account, through re-injection of the gas into the reservoir, Total environmental policy imposing the recycling of production gas. Monitoring of this injection was the main reason to shoot the first High Resolution 4D extremely early in the life of field. Despite the complexity of interpretation due to complex fluid situation and pressure effect, the results went way beyond expectations as the 4D images are of very high quality. Data has also been used to update and refine the reservoir flow model as well ...

2004-07-01

310

Failure analysis and defect review using extended accuracy of the CrossBeam {sup registered} Technology  

Energy Technology Data Exchange (ETDEWEB)

The use of the focused ion beam (FIB) systems has increased to a high level in recent years. The imaging, milling, and deposition capabilities of the FIB make it the ideal instrument for e.g., site-specific failure analysis, specimen preparation and nano-machining. Ion channelling contrast allows for selective imaging of polycrystalline and polyphase microstructures. In addition, the FIB and CrossBeam registered instruments are unique stand-alone analytical tools. Their vast capabilities have enabled numerous applications into the semiconductor and materials sciences applications. These integrated CrossBeam registered Tools enable the observation and direct control of the FIB operation in real time. In addition to the improved accuracy and resolution the electron beam adds analytical capabilities as STEM, EDS and EBSP to the instruments. To ensure a safe and reliable operation of the instrument, a dedicated vacuum system is needed. This type of ...

2005-07-01

311

High-resolution magnetic resonance imaging: three-dimensional trabecular bone architecture and biomechanical properties.  

Science.gov (United States)

The purpose of this study was to use high-resolution magnetic resonance (MR) imaging combined with image analysis to investigate the three-dimensional (3D) trabecular structure, anisotropy, and connectivity of human vertebral, femoral, and calcaneal specimens. The goal was to determine whether: (a) MR-derived measures depict known skeletal-site-specific differences in architecture and orientation of trabeculae; (b) 3D architectural parameters combined with bone mineral density (BMD) improve the prediction of the elastic modulus using a fabric tensor formulation; (c) MR-derived 3D architectural parameters combined with BMD improve the prediction of strength using a multiple regression model, and whether these results corresponded to the results obtained using higher resolution depictions of trabecular architecture. A total of 94 specimens (12 x 12 x 12 mm cubes) consisting of trabecular bone only were obtained, of which there were 7 from the ...

1998-05-01

312

Multi-modality imaging of uveal melanomas using combined PET/CT, high-resolution PET and MR imaging  

Energy Technology Data Exchange (ETDEWEB)

We investigated the efficacy of combined FDG-PET/CT imaging for the diagnosis of small-size uveal melanomas and the feasibility of combining separate, high-resolution (HR) FDG-PET with MRI for its improved localization and detection. Patients, methods: 3 patients with small-size uveal melanomas (0.2-1.5 ml) were imaged on a combined whole-body PET/CT, a HR brain-PET, and a 1.5 T MRI. Static, contrast-enhanced FDG-PET/CT imaging was performed of head and torso with CT contrast enhancement. HR PET imaging was performed in dynamic mode 0-180 min post-injection of FDG. MRI imaging was performed using a high-resolution small-loop-coil placed over the eye in question with T2-3D-TSE and T1-3D-SE with 18 ml Gd-contrast. Patients had their eyes shaded during the scans. Lesion visibility on high-resolution FDGPET images was graded for confidence: 1: none, 2: suggestive, 3: clear. Mean tumour activity was calculated for summed image ...

2008-07-01

313

Understanding the distribution and architecture of algal mound reservoirs through outcrop-based high-resolution sequence stratigraphy: An example from the paradox basin, USA  

Energy Technology Data Exchange (ETDEWEB)

An outcrop-based study combining detailed lithofacies analysis with high-resolution sequence stratigraphy in the Paradox Basin, southwestern United States. has shown that complex lateral and vertical facies variations occur in relatively consistent and predictable patterns. Large-scale facies shifts of several kilometers occur across major sequence boundaries whereas small-scale lateral and vertical variations develop from stacking of individual cycles. Understanding of vertical stacking patterns and lateral distribution of facies in outcrop can be directly applied to both three-dimensional distribution of reservoir facies in the subsurface as well as the evaluation of heterogeneity within individual reservoirs. The Desert Creek and Ismay intervals of the Paradox Formation (Pennsylvanian) exposed along the San Juan River in southeastern Utah are characterized by high-frequency cyclic repetition of carbonate and siliciclastic facies controlled ...

1995-08-01

314

High resolution seismic refraction method with multichannel digital data acquisition system; Digital ta channel sokutei system wo mochiita koseido kussetsuho jishin tansa  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces a multichannel digital data acquisition system and examples of measurements with the system in seismic exploration using the high resolution seismic refraction method. The high resolution seismic refraction system performs analyses nearly automatically by using a computer after initial travel time has been read. Therefore, the system requires high-accuracy travel time data, for which a multichannel digital measuring instrument developed recently for seismic exploration using the refraction method has been used for the measurement. The specification specifies the number of channels at 144 as a maximum, a sampling time of 62.5 {mu}sec to 4 m sec, the maximum number of sampling of 80,000 samples, and gain accuracy of {plus_minus} 1%. The system was used for surveying a tunnel having a maximum soil cover of about 800 m. The traverse line length is about 6 km, the ...

1997-05-27

315

Experimental Study of Hypernuclei Electroproduction by High Precision Spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

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

2009-12-01

316

SERAPHIM: A propulsion technology for fast trains  

Energy Technology Data Exchange (ETDEWEB)

The Segmented Rail Phased Induction Motor (SERAPHIM) is a compact, pulsed linear induction motor (LIM) offering a unique capability for very high speed train propulsion. It uses technology developed for the Sandia coilgun, an electromagnetic launcher designed to accelerate projectiles to several kilometers per second. Both aluminum cylinders and plates were accelerated to a kilometer per second (Mach 3) by passing through a sequence of coils which were energized at the appropriate time. Although this technology was developed for ultra-high velocity, it can be readily adapted to train propulsion for which, at sea level, the power required to overcome air resistance limits the operational speed to a more modest 300 mph. Here, the geometry is reversed. The coils are on the vehicle and the ``projectiles`` are fixed along the roadbed. SERAPHIM operates not by embedding flux in a conductor, but by excluding it. In this propulsion scheme, pairs of ...

1995-06-01

317

The vital importance of GIS : a workshop in project siting and development  

Energy Technology Data Exchange (ETDEWEB)

Geographic information system (GIS) technology is now being used by wind energy developers who are required to consider and accommodate a wide variety of environmental and social considerations. This poster presentation discussed some of the new features available in current GIS technologies. High resolution imagery from satellites is being used to verify the accuracy of collected spatial data, as well as to investigate potential locations for meteorological towers, turbine sites, and roads. Slopes are easily calculated using GIS software tools, and digital elevation data can be used with high resolution aerial photography to determine routes for new roads and to establish available sites for crane pads. The GIS tools allow developers to consider protected ecological areas, wetlands and forests, and gives them the ability to better report project development considerations at public consultations. Wind ...

2010-07-01

318

The optical emission nebulae in the vicinity of WR 48 (Theta Mus); True Wolf-Rayet ejecta or unconnected supernova remnant?  

CERN Document Server

During searches for new optical Galactic supernova remnants (SNRs) in the high resolution, high sensitivity Anglo-Australian Observatory/United Kingdom Schmidt Telescope (AAO/UKST) HAlpha survey of the southern Galactic plane, we uncovered a variety of filamentary and more diffuse, extensive nebular structures in the vicinity of Wolf-Rayet (WR) star 48 (Theta Muscae), only some of which were previously recognised. We used the double-beam spectrograph of the Mount Stromlo and Siding Spring Observatory (MSSSO) 2.3-m to obtain low and mid resolution spectra of selected new filaments and structures in this region. Despite spectral similarities between the optical spectra of WR star shells and SNRs, a careful assessment of the new spectral and morphological evidence from our deep HAlpha imagery suggests that the putative shell of Theta Mus is not a WR shell at all, as has been commonly accepted, but is ...

2009-01-01

319

Study on the stability of the Maytenus aquifolium Martius chemical components submitted to ionizing radiation (X-ray and #gamma#)  

International Nuclear Information System (INIS)

The interest for medicinal plants has raised again in the last decades, after overcoming a declination period caused by the advances in the researches and development of the synthetic drugs industries. This growing interest has been stimulated mainly by searching cheap and accessible alternative therapies. However, in order to have natural products based treatment in an efficient and safety way, it is necessary to guarantee the plant authenticity, finding adulterations and to assure a low level of microbiological contaminations to avoid damages to consumer's health. The decontamination method should be chosen for eliminating or reduce the microorganisms level without loss of the plant active constituents that would destroy its therapeutic action. At the present work, the possibility of using #gamma# and X electromagnetic radiations to sterilize a Brazilian medicinal plant (Maytenus aquifolium Martius, Celastraceae), which shows anti-ulcer activity, was studied by accomplishing its ...

320

Remote sensing monitoring method of hyperspectral and high-resolution for underground coal bed combustion  

Energy Technology Data Exchange (ETDEWEB)

Human beings are confronted with another grievous disaster - coal fire. The monitoring on underground coal bed combustion relied on drilling supervising in the past, but this method is not good. By taking the coal fire of Gulaben mine in Inner Mongolia Autonomous Region as an example, the monitoring methods of underground coal bed combustion were explored based on the hyperspectra and high-resolution remote sensing technology. By employing the OMIS imaging apparatus developed by Shanghai Institute of Technical Physics of Chinese Academy of Sciences, the airborne hyperspectral images and the characteristic spectra of different types were obtained and the temperature was measured synchronously on the ground. Then according to the correlation of DN value of the thermal infrared band and surface temperature, the image information was processed, the spectral features were analyzed, and the surface temperature retrieval model was built. Finally, by hyperspectral imagery ...

2007-10-15

321

Recent Progress in CdTe and CdZnTe Detectors  

CERN Document Server

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and Gamma-ray detection. The high atomic number of the materials (Z_{Cd} =48, Z_{Te} =52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg ~ 1.5 eV) allows us to operate the detector at room temperature. However, a considerable amount of charge loss in these detectors produces a reduced energy resolution. This problem arises due to the low mobility and short lifetime of holes. Recently, significant improvements have been achieved to improve the spectral properties based on the advances in the production of crystals and in the design of electrodes. In this overview talk, we summarize (1) advantages and disadvantages of CdTe and CdZnTe semiconductor detectors and (2) technique for improving energy resolution and photopeak efficiencies. ...

2001-01-01

322

Numerical modeling of slug flow initiation in a horizontal channels using a two-fluid model  

International Nuclear Information System (INIS)

This paper presents a methodology for modeling slug initiation and growth in horizontal ducts. Transient two-fluid equations are solved numerically using a class of high-resolution shock capturing methods. The advantage of this method is that slug formation and growth in a stratified regime can be calculated directly from the solutions to the flow field differential equations. In addition, by using high-resolution shock capturing methods that do not contain numerical diffusion, the discontinuity generated by slugging in the flow field can be modeled with good accuracy. The two-fluid model is shown to be well-posed mathematically only under certain conditions. Under these circumstances, the two-fluid model is capable of correctly predicting and modeling the flow physics. When ill-posed, an unbounded instability occurs in the flow field solution, and the instability amplitude increases exponentially with decreasing mesh sizes. This work shows ...

2011-02-01

323

Multi-wavelength observations of the young binary system Haro 6-10: The case of misaligned discs  

CERN Document Server

Context. We present a multi-wavelength, high-resolution observational survey of the young binary system Haro 6-10 (GV Tau, IRAS 04263+2426), which is harbouring one of the few known infrared companions. Aims. The primary goal of this project is to determine the physical and geometrical properties of the circumstellar and circumbinary material in the Haro 6-10 system. Methods. High-resolution optical (HST/WFPC2) and near-infrared (VLT/NACO) images in different bands were analysed to investigate the large-scale structures of the material around the binary.Mid-infrared interferometry (VLTI/MIDI) and spectroscopy (TIMMI2 at the 3.6m ESO telescope) were carried out to determine the structure and optical depth of the circumstellar material around the individual components. Results. The multi-wavelength observations suggest that both components of the binary system Haro 6-10 are embedded in a common envelope. The measured extinction indicates a dust ...

2011-01-01

324

Magnetic resonance imaging of the hip with a pelvic phased-array surface coil: a technical note  

Energy Technology Data Exchange (ETDEWEB)

Objective. The aim of this study was to assess the capability of high-resolution images obtained with a commercially available pelvic phased-array surface coil to demonstrate normal hip anatomy. Design. We retrospectively analyzed the oblique coronal magnetic resonance (MR) images of hips of 36 consecutive patients acquired on a 1.5-T clinical imager using a pelvic phased-array coil as a receiver, a 16-20 cm field of view, and 5 mm slice thickness. Patients. Thirty-six patients were studied, age 15-81 years. There were 20 males and 16 females. Results and conclusions. The articular cartilage, cortex, superior labrum, and iliofemoral ligament were well visualized on proton density weighted fat saturation (PDF) images. The femoral and obturator vessels, obturator nerve, and various muscles were easily seen on T1-weighted images. High-resolution imaging of the hip is achievable in a reasonable amount of time using newer phased-array surface coils ...

1998-02-01

325

In-situ focused ion beam (FIB) microscopy at high temperature  

International Nuclear Information System (INIS)

Materials Scientists need information on the kinetics of the microstructural evolution processes that determine the finished microstructure, and hence the properties, of any material. E.g. recrystallisation, grain growth and phase changes. Such kinetic information requires reliable discrimination of differently oriented crystallites and/or different crystal phases coupled with useful spatial resolution and temporal resolution (i.e. high frame rates). These imaging results must be realised from a hot and changing specimen, in an instrument that is compatible with that hot specimen and with a practical specimen heater. Focused Ion Beams (FIB) offer strong contrast between crystallites and phases, and hence offer the ability to discriminate between these features even while imaging at fast frame rates, however their compatibility with hot specimens was unproven. Here we report results from a novel combination of FIB with an ...

2008-08-01

326

High-resolution stratigraphy in a Miocene reservoir of the Niger delta  

Energy Technology Data Exchange (ETDEWEB)

High-resolution sequence stratigraphy concepts are applied to Erema, a Miocene onshore field of the Niger delta. The field's production is decreasing and an up-to-date geological model is essential to monitor the production. We aim to show an approach, using subsurface data and sequence stratigraphic concepts, which results in a time-line (Maximum Flooding Surfaces) correlation scheme. This scheme is based upon a facies model and is destined to guide the study of the characterization of reservoir heterogeneities. Using the cored well as a reference point, the facies model consists of shoreface dunes (planar tabular cross-stratified sandstones) changing landward into fluvial distributary deposits (through cross-stratified sandstones) via a tide-influenced coastal plain facies. The stacking pattern of genetic units shows a seaward stepping phase at the reservoir scale (sixty metres thick) with an abrupt deepening at the top of the reservoir. The proposed ...

1994-06-30

327

High-resolution sequence stratigraphy of a Hettangian-Sinemurian parallic succession, Bornholm, Denmark  

Energy Technology Data Exchange (ETDEWEB)

Sequence stratigraphic interpretation of paralic successions is complicated by the complex interfingering of marine and continental strata. The successions may also include terrestrial extensions of marine parasequences and completely independent lacustrine parasequence analogues. Failure in recognizing the possible interbedding of these two independent parasequence types may lead to construction of sequence stratigraphic schemes based on incompatible data sets. We have studied a Lower Jurassic paralic section from the Baltic island of Bornholm. The Hettangian-Sinemurian Sose Bugt Member (Ronne Formation) of Bornholm includes lacustrine, fluvial and restricted marine, estuarine deposits reflecting the basin-margin position. Biostatigraphic resolution is poor and a sequence stratigraphic interpretation of the paralic succession is far from straightforward. A multidisciplinary approach including facies analysis, recognition and lateral tracting of key surface, ...

1995-04-01

328

High resolution spectroscopy of second overtone transitions in solid parahydrogen  

Energy Technology Data Exchange (ETDEWEB)

The high resolution spectrum of the parahydrogen Q{sub 3}(0) transition at 11758 cm{sup -1} has allowed specific quantum state assignment of the ten lines which compose this transition. The transition cannot occur unless a dipole moment is induced in the parahydrogen by an external field. The quadrupole field of an impurity o-H{sub 2} molecule provides this field, and the transition occurs in the orientationally dependent field of the orthohydrogen molecule. Transitions induced by the quadrupolar field of the J=1 H{sub 2} in the nearest neighbor as well as in the next nearest neighbor shells have been observed. By lowering the impurity orthohydrogen concentration, the authors have observed lines with linewidths of approximately 15 MHz hwhm with a Ti:Sapphire laser having a sensitivity of 3x10{sup -5} ({Delta}I/I) using the toneburst method. Additionally, the second vibrational overtone of the impurity orthohydrogen molecule (Q{sub 3}(1)) has ...

1995-12-31

329

High resolution scanning electron microscopy of plasmodesmata.  

Science.gov (United States)

Symplastic transport occurs between neighbouring plant cells through functionally and structurally dynamic channels called plasmodesmata (PD). Relatively little is known about the composition of PD or the mechanisms that facilitate molecular transport into neighbouring cells. While transmission electron microscopy (TEM) provides 2-dimensional information about the structural components of PD, 3-dimensional information is difficult to extract from ultrathin sections. This study has exploited high-resolution scanning electron microscopy (HRSEM) to reveal the 3-dimensional morphology of PD in the cell walls of algae, ferns and higher plants. Varied patterns of PD were observed in the walls, ranging from uniformly distributed individual PD to discrete clusters. Occasionally the thick walls of the giant alga Chara were fractured, revealing the surface morphology of PD within. External structures such as spokes, spirals and mesh were observed surrounding the PD. ...

2011-05-28

330

High resolution Fourier transform spectroscopy and crystal-field analysis in Tm,Ho:BaY{sub 2}F{sub 8}  

Energy Technology Data Exchange (ETDEWEB)

A Tm{sup 3+}- Ho{sup 3+} -codoped single crystal of monoclinic BaY{sub 2}F{sub 8} has been characterized by means of high resolution FTIR spectroscopy in the wave number range 2000-24000 cm{sup -1} and in the temperature range 9-300 K. The energy level schemes of the two lanthanide ions as determined by the optical absorption spectra is presented, analyzed, and fitted within a single ion Hamiltonian model. The very small energy separation (about 0.6-1.6 cm{sup -1}) measured between the first and second sublevels of the ground state manifolds for both the ions is in line with the theoretical predictions. The impurity-phonon coupling is put into evidence by the thermally induced line shift and broadening, and by the detection of vibronic replicas of a few lines. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2005-01-01

331

High resolution Fourier transform spectroscopy and crystal-field analysis in Tm,Ho:BaY_2F_8  

International Nuclear Information System (INIS)

A Tm"3"+- Ho"3"+ -codoped single crystal of monoclinic BaY_2F_8 has been characterized by means of high resolution FTIR spectroscopy in the wave number range 2000-24000 cm"-"1 and in the temperature range 9-300 K. The energy level schemes of the two lanthanide ions as determined by the optical absorption spectra is presented, analyzed, and fitted within a single ion Hamiltonian model. The very small energy separation (about 0.6-1.6 cm"-"1) measured between the first and second sublevels of the ground state manifolds for both the ions is in line with the theoretical predictions. The impurity-phonon coupling is put into evidence by the thermally induced line shift and broadening, and by the detection of vibronic replicas of a few lines. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2005-01-01

332

Depth profiling using C{sub 60} {sup +} SIMS-Deposition and topography development during bombardment of silicon  

Energy Technology Data Exchange (ETDEWEB)

A C{sub 60} {sup +} primary ion source has been coupled to an ion microscope secondary ion mass spectrometry (SIMS) instrument to examine sputtering of silicon with an emphasis on possible application of C{sub 60} {sup +} depth profiling for high depth resolution SIMS analysis of silicon semiconductor materials. Unexpectedly, C{sub 60} {sup +} SIMS depth profiling of silicon was found to be complicated by the deposition of an amorphous carbon layer which buries the silicon substrate. Sputtering of the silicon was observed only at the highest accessible beam energies (14.5 keV impact) or by using oxygen backfilling. C{sub 60} {sup +} SIMS depth profiling of As delta-doped test samples at 14.5 keV demonstrated a substantial (factor of 5) degradation in depth resolution compared to Cs{sup +} SIMS depth profiling. This degradation is thought to result from the formation of an unusual platelet-like grain structure on the SIMS ...

2006-07-30

333

Cosmological Hydrodynamics with Adaptive Mesh Refinement a new high resolution code called RAMSES  

CERN Document Server

A new N-body and hydrodynamical code, called RAMSES, is presented. It has been designed to study structure formation in the universe with high spatial resolution. The code is based on Adaptive Mesh Refinement (AMR) technique, with a tree based data structure allowing recursive grid refinements on a cell-by-cell basis. The N-body solver is very similar to the one developed for the ART code (Kravtsov et al. 97), with minor differences in the exact implementation. The hydrodynamical solver is based on a second-order Godunov method, a modern shock-capturing scheme known to compute accurately the thermal history of the fluid component. The accuracy of the code is carefully estimated using various test cases, from pure gas dynamical tests to cosmological ones. The specific refinement strategy used in cosmological simulations is described, and potential spurious effects associated to shock waves propagation in the resulting AMR grid are discussed and ...

2001-01-01

334

Clinical evaluation of life size image of Fuji computed radiography for detection of diffuse interstitial lung diseases  

Energy Technology Data Exchange (ETDEWEB)

To evaluate the diagnostic accuracy of Fuji computed radiography (FCR) in the detection of interstitial pulmonary infiltrates, FCR life-size images at a pixel size of 0.1 mm were compared with conventional radiographs taken on the same day. Seventeen radiologists assessed the radiographs and FCR images of 56 cases, including 39 cases of various interstitial lung diseases such as interstitial pneumonia, pulmonary abnormalities associated with collagen disease, sarcoidosis, multiple pulmonary metastases, diffuse panbronchiolitis and pulmonary emphysema, and 17 normal controls. All of the pulmonary abnormalities were confirmed by high resolution CT. Observer performance tests were carried out using receiver operating characteristic analysis. In 21 cases of increased pulmonary density revealed by high resolution CT, FCR was significantly superior to conventional radiographs in the detection of reticular or ...

1991-11-01

335

Clinical evaluation of life size image of Fuji computed radiography for detection of diffuse interstitial lung diseases  

International Nuclear Information System (INIS)

To evaluate the diagnostic accuracy of Fuji computed radiography (FCR) in the detection of interstitial pulmonary infiltrates, FCR life-size images at a pixel size of 0.1 mm were compared with conventional radiographs taken on the same day. Seventeen radiologists assessed the radiographs and FCR images of 56 cases, including 39 cases of various interstitial lung diseases such as interstitial pneumonia, pulmonary abnormalities associated with collagen disease, sarcoidosis, multiple pulmonary metastases, diffuse panbronchiolitis and pulmonary emphysema, and 17 normal controls. All of the pulmonary abnormalities were confirmed by high resolution CT. Observer performance tests were carried out using receiver operating characteristic analysis. In 21 cases of increased pulmonary density revealed by high resolution CT, FCR was significantly superior to conventional radiographs in the detection of reticular or ...

1991-01-01

336

Bulk-sensitive high-resolution photoemission study of a temperature-induced valence transition system EuPd{sub 2}Si{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

Eu 4f electronic structures of a temperature-induced valence transition system EuPd{sub 2}Si{sub 2} have been investigated by bulk-sensitive high-resolution photoemission spectroscopy at temperatures from 20 to 300 K. The bulk Eu{sup 2+} 4f component is definitely distinguished from two surface Eu{sup 2+} 4f components. The changes in the spectral intensity of the bulk Eu{sup 2+} and Eu{sup 3+} 4f configurations and in the energy separation between these states are observed in the temperature dependent photoemission spectra. These temperature dependences are related to the valence transition of EuPd{sub 2}Si{sub 2}. The Eu mean valence is evaluated to be 2.75{+-}0.03 at 20 K and 2.30{+-}0.05 at 300 K. These values are in good agreement with those evaluated from Moessbauer and Eu L{sub III}-edge X-ray absorption measurements.

2004-07-01

337

Position sensitive detection of individual nuclear particle scintillations using image intensifier tubes  

International Nuclear Information System (INIS)

An imaging position sensitive detector for charged particles, neutrons, X-and gamma rays has been developed. The novel feature of this scintillation imaging radiation detector is its ability to detect individual nuclear particle scintillations with a h igh degree of spatial resolution. The key elements of this detector system are a high gain, low noise image intensifier tube, a CCD camera and commercially available image processing hardware and software. This detector system is highly effective for applications such as low fluence and real time neutron radiography, mapping of radioactive contamination in nuclear reactor fuel rods, X-ray diffraction imaging, high speed autoradiography and in general position sensitive detection of nuclear radiation. Results of some of the exploratory experiments carried out using this detector system are presented in this paper. (orig.).

1996-01-01

338

Neutron cross-sections for next generation reactors: New data from n_TOF  

International Nuclear Information System (INIS)

In 2002, an innovative neutron time-of-flight facility started operation at CERN: n_TOF. The main characteristics that make the new facility unique are the high instantaneous neutron flux, high resolution and wide energy range. Combined with state-of-the-art detectors and data acquisition system, these features have allowed to collect high accuracy neutron cross-section data on a variety of isotopes, many of which radioactive, of interest for Nuclear Astrophysics and for applications to advanced reactor technologies. A review of the most important results on capture and fission reactions obtained so far at n_TOF is presented, together with plans for new measurements related to nuclear industry.

2008-06-22

339

Framework for high-resolution climate change impact assessment on grapevines at a regional scale  

British Library Electronic Table of Contents (United Kingdom)

Understanding the impacts of climate change on viticulture is especially essential in those areas producing high-quality wines. In this work, we create an operational framework to investigate climate change impact on viticulture in the Tuscany region (central Italy) the viticulture industry of which relies on producing high-quality wines to compete in a global market. The framework includes (i) statistical downscaling of General Circulation Model (GCM) outputs for the period 1975?2099 to a local scale; (ii) the use of downscaling outputs as driving variables in specific simulation models; (iii) the spatial interpolation of model outputs to feed an economic and (iv) a quality model. The results show that as a consequence of a progressive increase in temperature and a decrease in rainfall, (...

2011-01-01

340

ALOS satellite imagery utilizations for safeguards  

International Nuclear Information System (INIS)

This paper introduces examples of satellite imageries analysis and utilizations for safeguards activities. Recently, many kinds of satellite imageries are available in the world i.e., high-spatial resolution, multi- and hyper-spectral, multi-function, and multi-polarization radars. The problem is that how to obtain the required information from these digital images. The Japan Aerospace Exploration Agency (JAXA) has successfully launched the Advanced Land Observing Satellite (ALOS, the nickname is 'Daichi') on 24th January, 2006. The mission objectives are cartography, regional observation, disaster monitoring etc. ALOS has three instruments, PRISM, AVNIR-2, and PALSAR, to achieve these objectives. An overview of ALOS is provided. ALOS follows the Japanese Earth Resources Satellite- 1 (JERS-1) and the Advanced Earth Observing Satellite (ADEOS) and utilizes advanced land-observing technology. ALOS is fling in a Sun-synchronous orbit with an ...

2006-10-16

341

Neutron-computer tomography using real-time neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

A real-time neutron radiography facility was constructed including the capability of neutron tomography. The neutron beam was measured for total neutron flux ((1.0 +/- 0.2) x 10/sup 11/ m/(m/sup 2/-sec)), gold cadmium ratio (52 +/- 3) and effective neutron temperature (83/sup 0/C +/- 8/sup 0/C). The angular divergence or nonparallelism of the neutron beam was measured to be 2.3/sup 0/ +/- 0.1/sup 0/ thereby providing a means of quantifying the collimator effectiveness. The resolution capabilities of both static film and real-time neutron radiographs were quantified using a Fourier transform algorithm to calculate the modulation transfer function of both types of radiographs. The contrast sensitivity of both types of radiographs. The contrast sensitivity of both types of radiographs was measured as 3.1% for film and 4.0% for real-time radiographs. Two tomography algorithms, the simultaneous iterative reconstruction technique (SIRT) and the convolution method, were ...

1986-01-01

342

Neutron-computer tomography using real-time neutron radiography  

International Nuclear Information System (INIS)

A real-time neutron radiography facility was constructed including the capability of neutron tomography. The neutron beam was measured for total neutron flux ((1.0 +/- 0.2) x 10"1"1 m/(m"2-sec)), gold cadmium ratio (52 +/- 3) and effective neutron temperature (83"0C +/- 8"0C). The angular divergence or nonparallelism of the neutron beam was measured to be 2.3"0 +/- 0.1"0 thereby providing a means of quantifying the collimator effectiveness. The resolution capabilities of both static film and real-time neutron radiographs were quantified using a Fourier transform algorithm to calculate the modulation transfer function of both types of radiographs. The contrast sensitivity of both types of radiographs. The contrast sensitivity of both types of radiographs was measured as 3.1% for film and 4.0% for real-time radiographs. Two tomography algorithms, the simultaneous iterative reconstruction technique (SIRT) and the convolution method, were programmed on an Intellect 100 ...

1986-01-01

343

State analysis of sulfur in coal and coal fly ash by double-crystal X-ray fluorescence spectrometry  

Energy Technology Data Exchange (ETDEWEB)

Double-crystal high-resolution x-ray fluorescence spectrometry was applied to the state analysis of sulfur in coal and related fly ash. For total sulfur, a proportional relationship exists between fluorescence intensities and the analytical values obtained by the oxygen-combustion method. Two oxidation states of sulfur were identified by a least square curve fitting method, by assuming that the spectrum profile is identical for each sulfur state but the intensity and position are different. The chemical state of sulfur in coal and remaining in fly ash is discussed.

1983-01-01

344

Species dependence of the emittances of sputter-generated negative ion beams  

Energy Technology Data Exchange (ETDEWEB)

We report experimental evidence of a previously unseen species-dependent effect in the transverse emittances of momentum analysed /sup 28/Si/sup -/, /sup 58/Ni/sup -/ and /sup 197/Au/sup -/ ion beams generated by caesium ion sputtering. The high-resolution emittance measurement techniques employed in this work have enabled us to estimate the energy spreads of these ion beams; differences in the widths of the energy distributions are the origin of the observed differences in emittances of the ion beams investigated. (author).

1989-04-14

345

Smart Acquisition EELS  

Energy Technology Data Exchange (ETDEWEB)

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

2010-07-01

346

Short term relative sea-level oscillations in Upper Devonian Nisku Formation (Alberta, Canada): application to hydrocarbon exploration and recent discoveries  

Energy Technology Data Exchange (ETDEWEB)

The relationship between short term relative sea-level oscillations and the reef, off-reef deposits geometry of an Upper Devonian third order sequence highstand of the Nisku Formation in west central Alberta was studied through the analysis of high resolution sequence stratigraphy. Hydrocarbon generation was reconstructed by total organic carbon values and migration patterns that were dependent on the geometry of three fourth order sequences. This stratigraphic reconstruction provided the key to recent hydrocarbon discoveries such as in the Brazeau southern reef margin.

1997-09-01

347

Selective enhancement of barium in the atmospheres of red giants  

Energy Technology Data Exchange (ETDEWEB)

High-resolution spectroscopy of 13 bright red giants and Ba stars shows selective enhancement of Ba in three of them, HD 65699 (Ba 2), ..cap alpha..TrA (K4 III), and epsilonPeg (K2 Ib). Infrared spectra available for HD 65699 show that Sr is enhanced, too. This selective enhancement is discussed in terms of a modified s-process which converts some of the pre-existing r- and s-process matter into the magic nuclei /sup 88/Sr and /sup 138/Ba.

1984-03-01

348

Reversible Movement of Homogenously Nucleated Dislocations in a #beta#-Titanium Alloy  

International Nuclear Information System (INIS)

We demonstrate reversible movement of (1/2)[110](110) dislocation loops generated from nanodisturbances in a #beta#-titanium alloy. High resolution transmission electron microscope observations during an in situ tensile test found three reversible deformation mechanisms, nanodisturbances, dislocation loops and martensitic transformation, that are triggered in turn with increasing applied stress. All three mechanisms contribute to the nonlinear elasticity of the alloy. The experiments also revealed the evolution of the dislocation loops to disclination dipoles that cause severe local lattice rotations.

2009-01-30

349

Recent observations of Cassiopeia A  

International Nuclear Information System (INIS)

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

350

Observation of stochastic resonance near a subcritical bifurcation  

Energy Technology Data Exchange (ETDEWEB)

A hysteretic subcritical period-doubling bifurcation is observed in the nonlinear strain dynamics of a magnetostrictive oscillator. The dynamic strain response of the magnetostrictive oscillator was observed with a high-resolution fiber optic interferometer. The effects of low-frequency modulation and band-limited stochastic fluctuations on such a bifurcation are investigated. Power spectral density measurements show that for an optimal value of externally injected noise the signal-to-noise ratio of a low-frequency modulation signal is enhanced by greater than 14 dB, thus indicating the first experimental observation of stochastic resonance near a bistable period-doubling bifurcation. 10 refs., 7 figs.

1993-01-01

351

New techniques for electron-ion collision studies  

International Nuclear Information System (INIS)

We have constructed an apparatus to study electron impact ionization of ions which should provide additional insight into the mechanisms involved. Using multiparameter coincidence techniques, we will detect both outgoing electrons from ionization process and will be able to analyze the momenta of both particles simultaneously. Coupled with a high resolution electron gun, this information should have broad application to the difficult problem of three bodies interacting via the long range Coulomb force. If sufficient accuracy can be achieved, information regarding the relative phase of the outgoing electron wavefunctions can be obtained.

352

Nanostructure of Si-Ge near-surface layers produced by ion implantation and laser annealing  

International Nuclear Information System (INIS)

An annealing with the nanosecond laser light pulse is applied for crystal lattice reconstruction of a disturbed near-surface layer, which was created in semiconductor material as a result of the implantation process. Radiation with energy density higher than the threshold value causes the melting of the surface layer and than the epitaxial recrystallization from the melt on a different substrate. Structural changes occurring in the Ge implanted Si crystals after annealing with different energy densities are investigated by means of the cross-section high-resolution transmission electron microscopy. (author)

2001-09-23

353

Large-scale absolute dent evaluation campaign  

International Nuclear Information System (INIS)

Steam generator tube denting is primarily caused by build-up of corrosion products at the tubesheet and the tube support plates. The mechanism of dent growth and the identification of tubes which should be removed from service have been studied. The practical outcome has been to prevent in-service tube leaks and to avoid unnecessary plugging of large numbers of tubes. A finite element study of tubesheet deformation (of pulled leaking tubes from reactors) was undertaken. Profilometry results for characterizing dents are given. Although several modifications have been made the high resolution profilometry system performance and the results obtained have proved satisfactory. (U.K.).

354

Imaging characterization of carbon nanotube tips modified using a focused ion beam  

International Nuclear Information System (INIS)

A carbon nanotube (CNT) tip, which assembled on the sharp end of a Si tip by dielectrophoresis, was structurally modified using focused ion beam (FIB). We described the imaging characterization of the FIB-modified CNT tip in noncontact AFM mode in terms of wear, deep trench accessibility, and imaging resolution. Compared to a conventional Si tip, the FIB-modified CNT tip was superior, especially for prolonged scanning over 10 h. We conclude that modified CNT tips have the potential to obtain high-quality images of nanoscale structures.

2007-06-15

355

Grain boundary dissociation by the emission of stacking faults  

Energy Technology Data Exchange (ETDEWEB)

A range of <110> symmetric tilt grain boundaries (GBs) are investigated in several fcc metals with simulations and high resolution electron microscopy. Boundaries with tilt angles between 50.5{degree} and 109.5{degree} dissociate into two boundaries 0.6 to 1.1 nm apart. The dissociation takes place by the emission of stacking faults from one boundary that are terminated by Shockley partials at a second boundary. This is a general mode of GB relaxation for low stacking fault energy metals. The reasons for the occurrence of this relaxation mode are discussed using the theory of GB dislocations.

1995-05-01

356

Florida State University - Explores! World Headquarters  

Science.gov (United States)

EXPLORES! (EXPloring and Learning the Operations and Resources of Environmental Satellites!) is an educational outreach program developed at Florida State University with the intention of introducing weather satellite receiving technology into the primary and secondary school classrooms. The website furnishes real time high resolution imagery and tropical updates. Visitors can find historical accounts of the civilian weather satellites launched by the United States. Educators can discover kindergarten through twelfth grade resources and curriculum. Users can learn how to become a part of the WXSAT-L community email list where weather satellite professionals, amateurs, and hobbyists converse about scientific, tracking, launching, and operations information.

357

Development of superconducting cryo-electron microscope and its applications  

International Nuclear Information System (INIS)

Recently, a superconducting cryo-electron microscope in which specimens are cooled to the liquid helium temperature (4.2 K) has been developed. The main components and functional features of this new microscope are reported together with application data on polyethylene, poly (4-methyl-1-pentene), valonia cellulose, rock salt, ice crystallites and ceramic superconductor. The resistance to electron radiation damage, of beam-sensitive specimens including polymers has been increased more than ten times. Thus, the microscope has made it possible to take high resolution images and to analyze the crystal-structure of micro-areas. (orig.).

1988-01-01

358

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

International Nuclear Information System (INIS)

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

359

Common envelope evolution  

British Library Electronic Table of Contents (United Kingdom)

The common envelope phase of binary star evolution plays a central role in many evolutionary pathways leading to the formation of compact objects in short period systems. Using three dimensional hydrodynamical computations, we review the major features of this evolutionary phase, focusing on the conditions that lead to the successful ejection of the envelope and, hence, survival of the system as a post common envelope binary. Future hydrodynamical calculations at high spatial resolution are required to delineate the regime in parameter space for which systems survive as compact binary systems from those for which the two components of the system merge into a single rapidly rotating star. Recent algorithmic developments will facilitate the attainment of this goal.

2010-01-01

360

Application of a novel high resolution mass spectrometric imaging technique to elucidate nitrogen and carbon nutrition of orchids.  

Environmental Research Database

DescriptionOrchids belong to the family Orchidaceae which, with around 20,000 species, is the largest in the Plant Kingdom. Orchids hold a particular fascination because of their spectacular flowers and the rarity of many species- which has increased in recent years as a result of plant collecting, intensification of agriculture and land use changes have placed many species in jeopardy. One feature of orchids that distinguishes them from many other plants is that their seeds are so reduced in size that th [continued...

2006-01-30

361

A hierarchical lattice structure and formation mechanism of ZnO nano-tetrapods  

International Nuclear Information System (INIS)

The existence of characteristic longitudinal optical and transverse optical phonons of cubic ZnO in ZnO nano-tetrapods is determined by Raman spectroscopy and first-principles calculations. Stacking sequence change at the boundary of the core and legs is also identified by high-resolution transmission electron microscopy. Based on this experimental and theoretical evidence, we demonstrate that the lattice structure of ZnO nano-tetrapods is hierarchical with a zinc blende core connecting to four wurtzite legs. Furthermore, we establish the atomic configuration and propose a formation mechanism induced by Laplace pressure in the initial growth stage of ZnO nano-tetrapods.

2009-08-12

362

Long-term high temperature fatigue properties of new structural materials for nuclear reactors  

Energy Technology Data Exchange (ETDEWEB)

This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10{sup -6}/s and its experimental verification could be carried out. And, it was also found that as a result of evaluation ...

2003-01-01

363

Long-term high temperature fatigue properties of new structural materials for nuclear reactors  

International Nuclear Information System (INIS)

This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10"-"6/s and its experimental verification could be carried out. And, it was also found that as a result of evaluation of ...

2003-01-01

364

High-resolution "1H magnetic resonance spectroscopy imaging at 1.5 and 3 Tesla of the human brain: development of techniques and applications for patients with primary brain tumors and multiple sclerosis  

International Nuclear Information System (INIS)

The aim of this work was to develop several strategies and software-packages for the evaluation of in-vivo-data of the human brain, which were acquired with high-resolution 1H-MRSI at 1.5 and 3 T. Several studies involving phantoms, volunteers and patients were performed. Quality assurance studies were conducted in order to evaluate the reproducibility of the applied MR-techniques at both field strengths. A qualitative comparison-study between MRSI-data from a 1.5 T clinical MR-scanner and a 3 T research MR-scanner showed the advantages of the more advanced MRSI sequences and higher field strength (3 T). A study involving patients with primary brain tumours (gliomas) was performed in cooperation with the Department of Neurosurgery (University of Erlangen-Nuremberg). The methods developed in the course of this study, such as the integration of MRS-data into a stereotactic-system, the segmentation of metabolic maps and the correlation with histopathological findings ...

365

High-Resolution Computed Tomography with Single-Slice Computed Tomography and 16-Channel Multidetector Computed Tomography: A Comparison Regarding Visibility and Motion Artifacts  

International Nuclear Information System (INIS)

Background: High-resolution computed tomography is the image procedure of choice in the evaluation of interstitial lung disease. Multidetector-row computed tomography provides the possibility of simultaneous reconstruction of thin and thick slices from the same raw data, acquired from one single series. Thus, it may be tempting to exclude the step-and-shoot series. Purpose: To compare high-resolution computed tomography (HRCT step-and-shoot) from single-slice CT (SSCT) and 16-channel multidetector CT (MDCT) in terms of visibility and motion artifacts, and to investigate whether thin images reconstructed from helical MDCT are equal to or better than conventional HRCT by SSCT in terms of visibility and motion artifacts. Material and Methods: 20 patients underwent HRCT step-and-shoot by SSCT (SSCT step-and-shoot) and MDCT (MDCT step-and-shoot), and a helical MDCT acquisition (MDCT helical). Images from four anatomical levels were analyzed in ...

2007-11-01

366

Considerations for the next Compton telescope mission  

International Nuclear Information System (INIS)

A high resolution Compton telescope has been identified by the Gamma Ray Astronomy Program Working Group (GRAPWG) as the highest priority major mission in gamma ray astrophysics following GLAST. This mission should provide 25-100 times improved sensitivity, relative to CGRO and INTEGRAL, for MeV gamma ray lines. It must have good performance for narrow and broad lines and for discrete and diffuse emissions. Several instrumental approaches are being pursued to achieve these goals. We discuss issues relating to this mission including alternative detector concepts, instrumental configurations, and background reduction techniques. We have pursued the development of position-sensitive solid-state detectors (Ge, Si) for a high spectral resolution Compton telescope mission. A #approx#1 m2 germanium Compton telescope of position-sensitive germanium detectors was the basis for one of the GRAPWG concepts. ...

2000-04-12

367

Advanced nanoscale separations and mass spectrometry for sensitive high-throughput proteomics  

Energy Technology Data Exchange (ETDEWEB)

We review recent development in separations and mass spectrometric instrumentation for sensitive and high-throughput proteomic analyses. These efforts have been primarily focused on the development of high-efficiency (separation peak capacity of ~103) nanoscale liquid chromatography (nanoLC; e.g., flow rates extending down to ~20 nL/min at optimal separation linear velocities through narrow packed capillaries) in combination with advanced mass spectrometry (MS), including high sensitivity and high resolution Fourier transform ion cyclotron resonance (FTICR) MS. This technology enables MS analysis of low nanogram-level proteomic samples (i.e., nanoscale proteomics) with individual protein identification sensitivity at the low zeptomole-level. The resultant protein measurement dynamic range can reach 106 for nanogram-sized proteomic samples, while more abundant proteins can be ...

2005-06-01

368

The influence of inclusion spacing and microstructure on the fracture toughness of the secondary hardening steel AF1410  

Energy Technology Data Exchange (ETDEWEB)

An approach to the ductile fracture of ultra high strength steels has been evaluated. According to this approach the critical crack tip opening, delta/sub IC/, will scale with X/sub 0/(R/sub V//R/sub I/vertical bar/sub R//sub 0/. X/sub 0/ is an average inclusion spacing and (R/sub V/R/sub I/)vertical bar/sub R//sub 0/ is the void radius divided by the radius of the inclusion nucleating the void evaluated at the average inclusion size. AF1410 was selected to test this approach because it has exceptionally high fracture toughness on aging at 510/sup 0/C and because its toughness varies markedly with aging temperature. The results from this and earlier work showed a linear relationship exists between delta/sub IC/ and X/sub 0/(R/sub V//R/sub I/)vertical bar /sub R//sub 0/ for values of delta/sub IC/ ranging from about 8 ..mu..m to 60 ..mu..m. The values of (R/sub V//R/sub I/)vertical bar /sub R//sub 0/ for AF1410 aged at ...

1987-07-01

369

High resolution electron microscopy of interfaces in fcc materials  

Energy Technology Data Exchange (ETDEWEB)

Modern high-resolution electron microscopy (HREM) instruments, which are capable of a point-to-point resolution of better than 0.2 nm, have allowed atomic-scale observations of a variety of internal interfaces. The application of the HREM technique to fcc model systems for the purpose of addressing a number of interface issues will be examined in this paper. Atomic structure observations for heterophase interfaces of metal/metal and metal/metal-oxide systems as well as HREM studies of grain boundaries in NiO and Au will be discussed with emphasis on generic structural features and the role of the interface plane. Comparisons between observed interface structures and atomistic computer modeling results have shown agreements for some interfaces, as well as certain differences in others. A number of structural features are common to both metal and oxide grain boundaries, as well as certain heterophase boundaries. Of particular importance in ...

1990-08-01

370

Focused ion beam assisted three-dimensional rock imaging at submicron scale  

Energy Technology Data Exchange (ETDEWEB)

Computation of effective flow properties of fluids in porous media based on three dimensional (3D) pore structure information has become more successful in the last few years, due to both improvements in the input data and the network models. Computed X-ray microtomography has been successful in 3D pore imaging at micron scale, which is adequate for many sandstones. For other rocks of economic interest, such as chalk and diatomite, submicron resolution is needed in order to resolve the 3D-pore structure. To achieve submicron resolution, a new method of sample serial sectioning and imaging using Focused Ion Beam (FIB) technology has been developed and 3D pore images of the pore system for diatomite and chalk have been obtained. FIB was used in the milling of layers as wide as 50 micrometers and as thin as 100 nanometers by sputtering of atoms from the sample surface. The focused ion beam, consisting of gallium ions (Ga+) accelerated by ...

2003-05-09

371

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

Science.gov (United States)

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

2006-12-01

372

Experimental and clinical studies on the usefulness and assessment of the angiographic images processed by a digital radiography system (FCR: Fuji Computed Tomography)  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to assess experimentally and clinically the usefulness of Fuji Computed Radiography (FCR) in angiographic examinations. FCR had a spatial resolution with much lower X-ray exposure doses, although the resolution of FCR was generally inferior to conventional films. When a contrast medium of 1% iodine concentration was used, FCR pinpointed a mass 1.5 mm in diameter; and conventional film could detect a mass 2.2 mm in diameter. The contrast of iodine in FCR examinations was stable. A high sensitivity of imaging plate allowed a wide range of visualization. In 148 selective angiographic examinatinons for 138 patients, FCR-subtraction images were superior to conventional film angiography for contrast resolution; it had a high sensitivity in detecting areas, such as the mediastimun and left lobe of the liver, and tumor stains in capillary phase. The capability ...

1989-06-01

373

Experimental and clinical studies on the usefulness and assessment of the angiographic images processed by a digital radiography system (FCR: Fuji Computed Tomography)  

International Nuclear Information System (INIS)

The purpose of this study was to assess experimentally and clinically the usefulness of Fuji Computed Radiography (FCR) in angiographic examinations. FCR had a spatial resolution with much lower X-ray exposure doses, although the resolution of FCR was generally inferior to conventional films. When a contrast medium of 1% iodine concentration was used, FCR pinpointed a mass 1.5 mm in diameter; and conventional film could detect a mass 2.2 mm in diameter. The contrast of iodine in FCR examinations was stable. A high sensitivity of imaging plate allowed a wide range of visualization. In 148 selective angiographic examinatinons for 138 patients, FCR-subtraction images were superior to conventional film angiography for contrast resolution; it had a high sensitivity in detecting areas, such as the mediastimun and left lobe of the liver, and tumor stains in capillary phase. The capability ...

1989-01-01

374

Digital subtraction angiography with scanning lazer stimulated luminescence  

International Nuclear Information System (INIS)

Fuji Computed Radiography (FCR) utilizes imaging plates of scanning lazer stimulated luminescence. FCR can be used for intravenous digital subtraction angiography (IVDSA) and for intraarterial studies because of tis high contrast and spatial resolution. Pixel size of the imaging plates for angiography is 0.2 mm. Experimentally, it could demonstrate a vessel 1 mm in diameter with a contrast of 0.1, when opacified with a contrast medium of 3 % iodine concentration, and could image a vessel 3 mm in diameter with contrast of 0.1, when opacified with 1 % contrast medium. A 20 % stenosed portion of a vessel 3 mm in diameter was identified when opacified with 3 % contrast medium, and a 20 % stenosed portion of a vessel 2 mm in diameter was identified when opacified with 10 % contrast medium. In 105 IVDSA examinations of 75 patients, FCR was superior to Digital Fluorography (DF) in spatial resolution, size of examination field, ...

1985-01-01

375

VSP reverse-time migration  

Energy Technology Data Exchange (ETDEWEB)

VSP reverse-time migration is a well adaptable wave equation migration method. Its control equation not only describes all-direction propagation of seismic wave but also removes interbed multiples. Clearbout's image principle is generalized to determine image conditions, real VSP data are used to determine boundary condition, and two way reflection-free wave equation is solved by making reverse-time extrapolation. In each step of extrapolation, the migration value at relevant image point is obtained by using the image condition. The complete migration of a seismic section is achieved when reverse-time extrapolation reaches the minimum image time. In this paper it is proved theoretically and practically that this method is applicable to any velocity variation and makes the migrated section have both good resolution and high S/N ratio. Besides, this method results in high processing efficiency.

1991-01-01

376

Study of some Ayurvedic Indian medicinal plants for the essential trace elemental contents by instrumental neutron activation analysis and atomic absorption spectroscopy techniques  

Energy Technology Data Exchange (ETDEWEB)

Elemental analysis of some medicinal plants used in the Indian Ayurvedic system was performed by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plants samples collected in summer, winter and rainy seasons was studied and the biological effects of these elements on human beings are discussed. (orig.)

2009-07-01

377

Real-time imaging for neutron radiography at KURRI  

International Nuclear Information System (INIS)

For neutron radiography (NR), photographic techniques have been mainly used for many years. To observe a dynamic event and to test many samples, the real-time neutron radiography (i.e. neutron television - NTV) system has been introduced at the E-2 experimental tube of the Kyoto University Research Reactor (KUR). The NTV system has been practically applied to penetrating the side plates containing boron burnable poison to test MTR type reactor fuel, to investigation of moving objects and to neutron computed tomography (NCT). New approaches using some advanced neutron converters, a high sensitive and resolution TV camera and a high performance image processing system are being undertaken for standard indicators, visualization on air-water two-phase flow, NCT and so on. (author).

1987-07-01

378

PET and MRI in cardiac imaging: from validation studies to integrated applications  

International Nuclear Information System (INIS)

Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and allows accurate detection of coronary artery disease by assessment of myocardial perfusion. Magnetic resonance imaging (MRI) provides high resolution anatomical images that allow accurate evaluation of ventricular structure and function together with detection of myocardial infarction. Potential hybrid PET/MR tomography may potentially facilitate the combination of information from these imaging modalities in cardiology. Furthermore, the combination of anatomical MRI images with the high sensitivity of PET for detecting molecular targets may extent the application of these modalities to the characterization of atherosclerotic plaques and to the evaluation of angiogenetic or stem cell therapies, for example. This article reviews studies using MRI and PET in parallel to compare their performance in cardiac ...

2009-03-01

379

Nanostructured nickel ferrite: A liquid petroleum gas sensor  

British Library Electronic Table of Contents (United Kingdom)

The present investigation deals with the synthesis of nanostructured nickel ferrite (NiFe2O4) and their liquid petroleum gas-sensing characteristics. The 15-20nm size nickel ferrite has been synthesized at 700degreeC by a simple molten-salt route using sodium chloride as grain growth inhibitor. These nanoparticles exhibit significantly high response towards liquid petroleum gas (LPG) in comparison with ethanol vapor, hydrogen sulfide, ammonia and hydrogen. The gas response towards various gases at their 200ppm concentrations is investigated at 200-450degreeC. Different characterization techniques have been employed, such as differential thermal analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission elec...

2009-01-01

380

Mesenchymal stem cell transplantation for diffuse alveolar hemorrhage in SLE  

British Library Electronic Table of Contents (United Kingdom)

Background. A 19-year-old girl was diagnosed with systemic lupus erythematosus, based on findings of arthritis, malar rash, positive antinuclear antibody test and high levels of antibodies to double-stranded DNA. Two months after diagnosis, the patient presented with a sudden drop in blood hemoglobin level. Several days later, she developed bloody sputum, rapidly progressive dyspnea and hypoxemia. High-resolution CT showed diffuse alveolar infiltrates in both lung fields.Investigations. Physical examination, complete blood count, erythrocyte sedimentation rate, urinalysis, 24-h urine protein excretion, fecal occult blood test, d-dimer test, acid hemolysis test, activated partial thromboplastin time and prothrombin time, direct and indirect Coombs tests, bone marrow smear, arterial blood ga...

2010-01-01

381

K/sub. beta. //K/sub. cap alpha. / X-ray intensity ratio following K-electron capture and radioisotope excitation  

Energy Technology Data Exchange (ETDEWEB)

The K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49 less than or equal to Z less than or equal to 82 following electron capture decay and photon excitation using /sup 241/Am and /sup 57/Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K/sub ..beta..//K/sub ..cap alpha../ values on the mode of excitation in the case of Mn and Fe is attributed to chemical effects, while no such dependence is found for the high-Z elements.

1987-01-01

382

Gamma spectrometric characterisation of industrially used African and Australian bauxites and their red mud tailings  

Energy Technology Data Exchange (ETDEWEB)

From their genesis by weathering and sedimentation, bauxites, the principal aluminium ores, contain appreciable amounts of uranium and thorium. High resolution gamma spectrometry with a high purity germanium detector was used for an analysis of four industrially used bauxites from Gondama, Sierra Leone; Boke, Guinea; Weipa, Queensland, Australia; Gove, Northern Territory, Australia. Significant differences in uranium to thorium ratios and in activities of the uranium and thorium daughters were observed for the four bauxites. It was found that the bauxite from Gondama, Sierra Leone has an activity of only 10% compared with the others. Red mud tailings from such a bauxite may well be used as an additive to bricks, which is now illegal for normal red mud from more active bauxites. (author).

1992-01-01

383

Gamma spectrometric characterisation of industrially used African and Australian bauxites and their red mud tailings  

International Nuclear Information System (INIS)

From their genesis by weathering and sedimentation, bauxites, the principal aluminium ores, contain appreciable amounts of uranium and thorium. High resolution gamma spectrometry with a high purity germanium detector was used for an analysis of four industrially used bauxites from Gondama, Sierra Leone; Boke, Guinea; Weipa, Queensland, Australia; Gove, Northern Territory, Australia. Significant differences in uranium to thorium ratios and in activities of the uranium and thorium daughters were observed for the four bauxites. It was found that the bauxite from Gondama, Sierra Leone has an activity of only 10% compared with the others. Red mud tailings from such a bauxite may well be used as an additive to bricks, which is now illegal for normal red mud from more active bauxites. (author).

384

Fetal magnetic resonance imaging of the brain: technical considerations and normal brain development  

International Nuclear Information System (INIS)

Fetal MRI examines non-invasively the unborn fetus. Ultrafast MRI sequences effectively suppress fetal motion. Multiple case reports and studies have shown that fetal MRI is particularly helpful in the evaluation of the central nervous system. The high contrast-to-noise ratio, the high spatial resolution, the multiplanar capabilities, the large field of view and the simultaneous visualisation of fetal and maternal structures have proven to be advantageous. Fetal MRI is particularly helpful in the evaluation of the normal and pathological development of the brain. Despite the fact that no side effects have been reported or are to be expected, the use of MRI during pregnancy is still limited to the second and third trimester of pregnancy. Magnetic resonance imaging contrast media are not to be used as it passes the placenta. Ultrasound remains the primary screening modality for fetal pathology; fetal MRI can serve as an ...

2002-08-01

385

Fetal MRI of pathological brain development  

International Nuclear Information System (INIS)

Because of the superior tissue contrast, high spatial resolution, and multiplanar capabilities, fetal magnetic resonance imaging (MRI) can depict fetal brain pathologies with high accuracy. Pathological fetal brain development may result from malformations or acquired conditions. Differentiation of these etiologies is important with respect to managing the actual pregnancy or counseling future pregnancies. As a widened ventricular system is a common hallmark of both maldevelopment and acquired conditions, it may cause problems in the differential diagnosis. Fetal MRI can provide detailed morphological information, which allows refinement of the diagnosis of ventricular enlargement in a large number of cases. Systematic work-up of morphological details that may be recognized on MR images provides an approach for achieving a correct diagnosis in cases of ventricle enlargement. (orig.)

2006-02-01

386

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants.  

Science.gov (United States)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distribution of stable iodine tablets is advised. PMID:20332130

2010-03-23

387

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants  

British Library Electronic Table of Contents (United Kingdom)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distrib...

2010-01-01

388

Digital processing to improve image quality in real-time neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Real-time neutron radiography (NTV) has been used for practical applications at the Kyoto University Reactor (KUR). At present, however, the direct image from the TV system is still poor in resolution and low in contrast. In this paper several image improvements are demonstrated, such as a frame summing technique, which are effective in increasing image quality in neutron radiography. Image integration before the A/D converter has a beneficial effect on image quality and the high quality image reveals details invisible in direct images, such as: small holes by a reversed image, defects in a neutron converter screen through a high quality image, a moving object in a contoured image, a slight difference between two low-contrast images by a subtraction technique, and so on. For the real-time application a contouring operation and an averaging approach can also be utilized effectively.

1985-01-01

389

Digital processing to improve image quality in real-time neutron radiography  

International Nuclear Information System (INIS)

Real-time neutron radiography (NTV) has been used for practical applications at the Kyoto University Reactor (KUR). At present, however, the direct image from the TV system is still poor in resolution and low in contrast. In this paper several image improvements are demonstrated, such as a frame summing technique, which are effective in increasing image quality in neutron radiography. Image integration before the A/D converter has a beneficial effect on image quality and the high quality image reveals details invisible in direct images, such as: small holes by a reversed image, defects in a neutron converter screen through a high quality image, a moving object in a contoured image, a slight difference between two low-contrast images by a subtraction technique, and so on. For the real-time application a contouring operation and an averaging approach can also be utilized effectively. (orig.).

1985-01-01

390

Determination of macro, micro nutrient and trace element concentrations in Indian medicinal and vegetable leaves using instrumental neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

Leafy samples often used as medicine in the Indian Ayurvedic system and vegetables were analyzed for 20 elements (As, Ba, Br, Ca, Ce, Cr, Cs, Co, Eu, Fe, K, La, Na, Rb, Sb, Sc, Sm, Sr, Th, Zn) by employing Instrumental Neutron Activation Analysis (INAA). The samples were irradiated at the 100 kW TRIGA-MAINZ nuclear reactor and the induced activities were counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector. The concentration of the elements in the medicinal and vegetable leaves and their biological effects on human beings are discussed.

1999-05-01

391

Chemically produced nanostructured ODS-lanthanum oxide-tungsten composites sintered by spark plasma  

British Library Electronic Table of Contents (United Kingdom)

High purity W and W-0.9La2O3 (wt.%) nanopowders were produced by a wet chemical route. The precursor was prepared by the reaction of ammonium paratungstate (APT) with lanthanum salt in aqueous solutions. High resolution electron microscopy investigations revealed that the tungstate particles were coated with oxide precipitates. The precursor powder was reduced to tungsten metal with dispersed lanthanum oxide. Powders were consolidated by spark plasma sintering (SPS) at 1300 and 1400degreeC to suppress grain growth during sintering. The final grain size relates to the SPS conditions, i.e. temperature and heating rate, regardless of the starting powder particle size. Scanning electron microscopy revealed that oxide phases were mainly accumulated at grain boundaries while the tungsten matrix ...

2011-01-01

392

The design and performance of a capacitance sensor for two-phase flow concentration measurements in a square duct  

Energy Technology Data Exchange (ETDEWEB)

The use of capacitance sensors for measuring phase concentrations in two-phase flow has gained popularity in recent years. In designing such sensors, there are many issues which must be considered in order to optimize performance: two-phase flow regime, permittivity of the phases, duct geometry, electrical shielding, desired spacial resolution of film thickness, and temperature variation in the flow field. These design issues are discussed and are used to optimize the design of a capacitance sensor which is used to measure vapor volume fraction in annular, two-phase vertical upflow and downflow in a square duct. The sensor was tested and implemented in a 12.7 mm square duct mounted in a flow boiling facility containing FC-72, a low permittivity dielectric fluid ({epsilon}{sub r} = 1.75). Using analytical modeling, an adjustable-length, parallel-plate design was developed and refined to achieve good sensitivity to flow conditions. The sensor output was calibrated ...

1995-12-31

393

Structure of Mg$_n$ and Mg$_n^+$ clusters up to n=30  

CERN Document Server

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 ...

2011-01-01

394

Rotation seismic sensor and its calibration; Kaiten seibun jishinkei no shisaku to kando no kentei  

Energy Technology Data Exchange (ETDEWEB)

Sensor has been developed for the measurement of seismic wave rotary components. The vertical axis rotary component sensor is constituted of four L22Ds, similar to each other in performance, fixed in a ring formation on a metal bed. The ring is 22cm in diameter, and the four coils are connected so that their outputs will be added up. A horizontal axis rotary component sensor is built in the similar way. The rotary component sensors are all connected to a spectrum analyzer for the measurement of micromotions. It is found that the four-L22D combination can detect a rotary component of 335mV/deg/s. The sensor can detect both vertical and horizontal components with roughly the same sensitivity. A ring-form combination of conventional electromagnetic seismometers, though only as a temporary expedient, can perform high-resolution detection of rotary components and determine the absolute values of earthquakes or noise levels. In the case of a gyrosensor available on the ...

1997-05-27

395

Resolution enhancement by subtraction of confocal signals taken at different pinhole sizes.  

Science.gov (United States)

Subtractive imaging in confocal fluorescence light microscopy is based on the subtraction of a suitably weighted widefield image from a confocal image. An approximation to a widefield image can be obtained by detection with an opened confocal pinhole. The subtraction of images enhances the resolution in-plane as well as along the optic axis. Due to the linearity of the approach, the effect of subtractive imaging in Fourier-space corresponds to a reduction of low spatial frequency contributions leading to a relative enhancement of the high frequencies. Along the direction of the optic axis this also results in an improved sectioning. Image processing can achieve a similar effect. However, a 3D volume dataset must be acquired and processed, yielding a result essentially identical to subtractive imaging but superior in signal-to-noise ratio. The latter can be increased further with the technique of weighted averaging in Fourier-space. A comparison ...

2003-01-01

396

Performance characterization of a volumetric breast ultrasound scanner  

Science.gov (United States)

The purpose of this project was to design, build, and characterize the performance of a volume breast ultrasound (VBUS) scanner that images the pendant breast. VBUS scanner design includes a: 1) clinical ultrasound scanner and transducer; 2) scanning table with a hole for the pendant breast; 3) rotational gantry; 4) probe mounting assembly; 5) compressionless breast stabilization device; 6) acquisition, control, reconstruction, and display software. Performance assessment characterized a variety of parameters including: spatial resolution, uniformity, and distortion using high and low contrast test objects in both horizontal and vertical scanning modes. The VBUS scanner modules have been constructed and initial performance evaluated. Approximately 300 scans are acquired over 360 degrees in 18 seconds. Reconstruction requires 25 ms per slice. Test object images depicted hyper- and hypo-echoic masses and demonstrated good ...

2007-03-01

397

High Spatial Resolution Optical and Radio Imagery of the Circumbinary Environment  

CERN Document Server

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

2004-01-01

398

Four small puzzles that Rosetta doesn't solve  

CERN Document Server

A complete macromolecule modeling package must be able to solve the simplest structure prediction problems. Despite recent successes in high resolution structure modeling and design, the Rosetta software suite fares poorly on deceptively small protein and RNA puzzles, some as small as four residues. To illustrate these problems, this manuscript presents extensive Rosetta results for four well-defined test cases: the 20-residue mini-protein Trp cage, an even smaller disulfide-stabilized conotoxin, the reactive loop of a serine protease inhibitor, and a UUCG RNA tetraloop. In contrast to previous Rosetta studies, several lines of evidence indicate that conformational sampling is not the major bottleneck in modeling these small systems. Instead, approximations and omissions in the Rosetta all-atom energy function currently preclude discriminating experimentally observed conformations from de novo models at atomic resolution. ...

2011-01-01

399

Fabrication and characterization of low aberration micrometer-sized electron lenses.  

Science.gov (United States)

Intrinsic spherical aberrations of electron lenses have been the major resolution limiting factor in electron microscopes for several decades. While effective correctors have recently been implemented, an alternative to correct these aberrations is to circumvent them by scaling down lens dimensions by several orders of magnitude. We have fabricated electrostatic lenses exhibiting one micrometer diameter apertures and evaluated their beam forming properties against predictions from numerical ray tracing simulations. It turns out that it is routinely possible to shape a paraxial low-energy electron beam by such micron-sized lenses. Beam profiles have been measured both at a distant detector as well as in a plane close to the lens. It is shown that the lens can form a parallel beam extending no more than 800 nm from the optical axes at a distance of 200 microm beyond the lens exit. We believe that these findings constitute a prerequisite to derive novel tools for ...

2010-04-24

400

Effect of alcohols and temperature on the direct chiral resolutions of fipronil, isocarbophos and carfentrazone-ethyl.  

Science.gov (United States)

The enantiomeric separations of three pesticides fipronil (asymmetric nitrogen), isocarbophos (asymmetric phosphorus) and carfentrazone-ethyl (asymmetric carbon) were studied on cellulose-tri(3,5-dimethylphenylcarbamate) chiral stationary phase using high-performance liquid chromatography under normal phase. The mobile phase was n-hexane with alcohols including ethanol, n-propanol, iso-propanol, n-butanol and iso-butanol as polar modifiers. The flow rate was 1.0 mL/min with UV detection at 280, 225 and 230 nm for fipronil, isocarbophos and carfentrazone-ethyl respectively. The influence of the modifiers and their volume content and temperature from 0 to 50 degrees C on the separations was investigated. The chiral stationary phase showed excellent stereoselectivity for the two enantiomers of fipronil and isocarbophos and certain chiral recognition for carfentrazone-ethyl. Iso-propanol was more suitable for the chiral separation of isocarbophos and ...

2005-07-01

401

A superconducting solenoidal spectrometer for a balloon-borne experiment  

Energy Technology Data Exchange (ETDEWEB)

The BESS detector is a new type of balloon-borne spectrometer which utilizes various technologies recently developed for collider experiments. The principal scientific objectives include a measurement of cosmic-ray antiproton spectrum, search for anti-nuclei in cosmic radiation, and precise measurements of cosmic-ray primaries. A thin superconducting solenoidal coil produces a uniform magnetic field of 1 T. Cylindrical drift chambers are located inside and outside the coil and perform continuous tracking. The momentum resolution is 0.5% at 1 GeV/c. i.e., the maximum detectable rigidity is 200 GV. Scintillation counter hodoscopes, placed above and below the solenoid, provide timing and dE/dx measurements and trigger generation. The timing resolution is 80 ps/counter. This cylindrical configuration achieves a large geometrical acceptance of 0.35 m{sup 2} sr which is essential to detect rare cosmic-ray particles. In order to cope with ...

2000-03-21

402

Non-catalytic and catalytic wet air oxidation of pharmaceuticals in ultra-pure and natural waters  

British Library Electronic Table of Contents (United Kingdom)

A wet air oxidation (WAO) process was applied to four selected pharmaceuticals (metoprolol, naproxen, amoxicillin, and phenacetin) individually dissolved in ultra-pure water, varying the temperature and oxygen pressure. Due to the moderate (amoxicillin) or low (metoprolol, naproxen, and phenacetin) efficiency found in the oxidation of these pollutants, a catalytic wet air oxidation (CWAO) process was then tested using a platinum catalyst supported on multi-walled carbon nanotubes (CNT). In this CWAO process, the pharmaceuticals were dissolved together in ultra-pure water and in four natural water matrices-a reservoir water, a groundwater, and two waters from different municipal wastewater treatment plants. On the basis of the measurements of their removals, a discussion is given of the inf...

2011-01-01

403

Machinability of magnesium alloy in ultra-precision diamond cutting  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with an experimental study of ultra-precision diamond cutting of magnesium alloy (AZ31). In order to investigate the machinability such as the cutting force and the surface integrity and understand the problems in a micro cutting, the experiments on the diamond cutting of magnesium alloy and pure aluminum with an ultra-precision turning machine has been carried out. The machinability of magnesium alloy was compared with that of pure aluminum and discussed. Consequently, both the thrust force component and the surface roughness obtained by cutting of magnesium alloy became larger than that of pure aluminum. It was also found that the inclusions or the defects in the work material caused to generate the scratches on the finished surface and influenced the integrity of mirror surface. (orig.)

2003-07-01

404

Identification of oxidation states of ultra-trace elements by radiation detection  

International Nuclear Information System (INIS)

The determination of the oxidation state of ultra-trace elements in the environment, especially in the case of actinides, is of importance in many ways. Speciation techniques using radiation may comprise methods based on the detection of the nuclear and atomic radiations emitted in radioactive decay or methods using external sources of excitation. In the former instance, information can be obtained from the energy and intensity of radiation, but at present the partition method is still the most commonly used, although its reliability is questionable. Excitation with intense laser beams, as is currently being used for trace element analysis in photoacoustic and thermal lensing spectroscopic techniques, could conceivably be applied under suitable conditions to ultra-trace elements with a sensitivity approaching that of the radiochemical methods.

1989-11-01

405

A numerical study of ultra-short-pulse reflectometry  

Energy Technology Data Exchange (ETDEWEB)

Ultra-short-pulse reflectometry is studied by means of the numerical integration of a one-dimensional full-wave equation for ordinary modes propagating in a plasma. The numerical calculations illustrate the potential of using the reflection of ultra-short-pulse, microwaves as an effective probe of the density profile even in the presence of significant density fluctuations. The difference in time delays of differing frequency components of the microwaves can be used to deduce the density profile. The modification of the reflected pulses in the presence of density fluctuations is examined and can be understood based on considerations of Bragg resonance. A simple and effective profile-reconstruction algorithm using the zero-crossings of the reflected pulse and subsequent Abel inversion is demonstrated. The robustness of the profile reconstruction algorithm in the presence of a sufficiently small amplitude density perturbation is assessed.

1994-05-01

406

Microstructural transformations and kinetics of high-temperature heterogeneous gasless reactions by high-speed x-ray phase-contrast imaging  

Science.gov (United States)

Heterogeneous gasless reactive systems, including high-energy density metal-nonmetal compositions, have seen increasing study due to their various applications. However, owing to their high reaction temperature, short reaction time, and small scale of heterogeneity, investigation of their reaction mechanisms and kinetics is very difficult. In this study, microstructural changes and the kinetics of product layer growth in the W-Si system was investigated using a high-speed x-ray phase-contrast imaging technique. Using the Advanced Photon Source of Argonne National Laboratory, this method allowed direct imaging of irreversible reactions in the W-Si reactive system at frame rates up to 36 000 frames per second with 4 {mu}s exposure and spatial resolution of 10 {mu}m. Details of the Si melt and reactions between W and Si, that are unable to be viewed with visible-light imaging, were revealed. These include ...

2009-12-01

407

Microstructural transformations and kinetics of high-temperature heterogeneous gasless reactions by high-speed x-ray phase-contrast imaging  

International Nuclear Information System (INIS)

Heterogeneous gasless reactive systems, including high-energy density metal-nonmetal compositions, have seen increasing study due to their various applications. However, owing to their high reaction temperature, short reaction time, and small scale of heterogeneity, investigation of their reaction mechanisms and kinetics is very difficult. In this study, microstructural changes and the kinetics of product layer growth in the W-Si system was investigated using a high-speed x-ray phase-contrast imaging technique. Using the Advanced Photon Source of Argonne National Laboratory, this method allowed direct imaging of irreversible reactions in the W-Si reactive system at frame rates up to 36 000 frames per second with 4 #mu#s exposure and spatial resolution of 10 #mu#m. Details of the Si melt and reactions between W and Si, that are unable to be viewed with visible-light imaging, were revealed. These include ...

2009-12-01

408

Nanofocusing refractive X-ray lenses  

Energy Technology Data Exchange (ETDEWEB)

This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is ...

2010-02-05

409

Surface Roughness of Stainless Steel Bender Mirrors for FocusingSoft X-rays  

Energy Technology Data Exchange (ETDEWEB)

We have used polished stainless steel as a mirror substrate to provide focusing of soft x-rays in grazing incidence reflection. The substrate is bent to an elliptical shape with large curvature and high stresses in the substrate require a strong elastic material. Conventional material choices of silicon or of glass will not withstand the stress required. The use of steel allows the substrates to be polished and installed flat, using screws in tapped holes. The ultra-high-vacuum bender mechanism is motorized and computer controlled. These mirrors are used to deliver focused beams of soft x-rays onto the surface of a sample for experiments at the Advanced Light Source (ALS). They provide an illumination field that can be as small as the mirror demagnification allows, for localized study, and can be enlarged, under computer control,for survey measurements over areas of the surface up to several millimeters. The critical issue of the quality of the ...

2005-10-11

410

Simulation of dopant diffusion and activation during flash lamp annealing  

International Nuclear Information System (INIS)

A set of advanced models implemented into the simulator Sentaurus Process was applied to simulate ultra shallow junction formation by flash lamp annealing (FLA). The full path transient enhanced diffusion model includes equations for small interstitial clusters (I_2, I_3, I_4), #left brace#3 1 1#right brace# defects and dislocation loops. A dopant-point defect clustering model is used for dopant activation simulation. Several cluster types are considered: B_2, B_2I, B_2I_2, B_3I, B_3I_2, B_3I_3 for boron and As_2, As_2V, As_3, As_3V, As_4, As_4V for arsenic. Different point defect and dopant-point defect pair charge states are taken into account to obtain accurate results in the high doping level region. The flux expressions in the three-phase segregation model include a dependence on the doping level and point defect supersaturation. The FLA process was performed at various peak temperatures in a Mattson Millios"T"M fRTP"T"M system. The ...

2008-12-05

411

New processing technique for forming flexible A-15 superconducting tapes with extremely high critical current densities  

Energy Technology Data Exchange (ETDEWEB)

A-15 compounds are extremely brittle and difficult to process for practical applications. A novel processing technique was developed to greatly improve the mechanical and superconducting properties of A-15 alloys. The new processing technique can be described as follows: (1) to select compounds that can form the A-15 phase (the selected A-15 compounds in this research were Ti3Nb6Mo3Si4 and Nb99.5-(x + y)AlxSiyB0.5 alloys); (2) to rapidly solidify them into the amorphous state; (3) to anneal the quenched amorphous products into ultra fine-grained single A-15 phase. The extreme grain refinement greatly improved the flexibility and the critical current density of the alloys. The melt spinning technique was used to rapidly solidify Ti3Nb6Mo3Si4 and Nb99.5-(x + y)AlxSiyB0.5 alloys. Ti3Nb6Mo3Si4 alloys were relatively easily formed into the amorphous state. Nb3Al alloys required the addition of glass forming elements Si and B. It was found that, without boron, the ...

1986-01-01

412

New processing technique for forming flexible A-15 superconducting tapes with extremely high critical current densities  

International Nuclear Information System (INIS)

A-15 compounds are extremely brittle and difficult to process for practical applications. A novel processing technique was developed to greatly improve the mechanical and superconducting properties of A-15 alloys. The new processing technique can be described as follows: (1) to select compounds that can form the A-15 phase (the selected A-15 compounds in this research were Ti3Nb6Mo3Si4 and Nb99.5-(x + y)AlxSiyB0.5 alloys); (2) to rapidly solidify them into the amorphous state; (3) to anneal the quenched amorphous products into ultra fine-grained single A-15 phase. The extreme grain refinement greatly improved the flexibility and the critical current density of the alloys. The melt spinning technique was used to rapidly solidify Ti3Nb6Mo3Si4 and Nb99.5-(x + y)AlxSiyB0.5 alloys. Ti3Nb6Mo3Si4 alloys were relatively easily formed into the amorphous state. Nb3Al alloys required the addition of glass forming elements Si and B. It was found that, without boron, the ...

413

Electrochemical and surface analytical studies of the interaction of nitrogen with key alloying elements in stainless steels  

Energy Technology Data Exchange (ETDEWEB)

Surface analytical studies of high nitrogen austenitic stainless steels exposed to deaerated 0.1M HCl have revealed that nitrogen alloying additions influence the composition of salt layers and the passive film/alloy interface. In this study the authors employ electrochemical techniques and variable angle X-ray Photoelectron Spectroscopy (XPS) to examine the passive films formed on a series of austenitic stainless steels, Fe18Cr8Ni, Fe18Cr8Ni0.2N, Fe20Cr20Ni, Fe20Cr20Ni6Mo and Fe20Cr20Ni6Mo0.2N, in acidic chloride aqueous solution. In addition, several other model alloys, Fe19Cr, Fe19Cr9Ni, Fe19Cr2.5Mo, and Fe19Cr9Ni2.5Mo, were examined before and after electrochemical surface nitriding, a technique proven to have an effect analogous to N alloying. It was shown that nitrogen, nickel and molybdenum additions independently and in certain combinations stimulate selective dissolution of iron, resulting in a significant enrichment of chromium beneath the passive film. ...

1995-12-01

414

Electrochemical and surface analytical studies of the interaction of nitrogen with key alloying elements in stainless steels  

International Nuclear Information System (INIS)

Surface analytical studies of high nitrogen austenitic stainless steels exposed to deaerated 0.1M HCl have revealed that nitrogen alloying additions influence the composition of salt layers and the passive film/alloy interface. In this study the authors employ electrochemical techniques and variable angle X-ray Photoelectron Spectroscopy (XPS) to examine the passive films formed on a series of austenitic stainless steels, Fe18Cr8Ni, Fe18Cr8Ni0.2N, Fe20Cr20Ni, Fe20Cr20Ni6Mo and Fe20Cr20Ni6Mo0.2N, in acidic chloride aqueous solution. In addition, several other model alloys, Fe19Cr, Fe19Cr9Ni, Fe19Cr2.5Mo, and Fe19Cr9Ni2.5Mo, were examined before and after electrochemical surface nitriding, a technique proven to have an effect analogous to N alloying. It was shown that nitrogen, nickel and molybdenum additions independently and in certain combinations stimulate selective dissolution of iron, resulting in a significant enrichment of chromium beneath the passive film. ...

1995-03-26

415

Demonstrating leadership inside and out : green building project trains employees, educates clients  

Energy Technology Data Exchange (ETDEWEB)

This article described a full-scale green renovation project undertaken by a construction management firm in Newton, Massachusetts. Chapman Construction and Design began renovating its own office building in late 2007 and completed it in September 2008. The firm set out to achieve LEED Platinum certification from the United States Green Building Council. The project involved energy saving modifications to its mechanical systems; replacing plumbing fixtures with high efficiency alternatives to reduce water consumption by at least 40 per cent; installing skylights and additional windows to allow more natural light into the interior space; salvaging doors, lighting, metal studs and masonry whenever possible; and using sustainable products such as recyclable carpets, tiles and low-VOC paint. The main feature of the renovation was a new 47 kW (DC) photovoltaic (PV) solar power array installed on the rooftop. The PV array includes 208 panels and a SunPower SPR-225 system ...

2009-01-15

416

Defect engineering via ion implantation to control B diffusion in Si  

International Nuclear Information System (INIS)

The processes which are currently studied in the fabrication of B-doped ultra shallow junctions (USJ) usually involve a preamorphization step to reduce B channelling effect during implantation and to improve B electrical activation. At this stage a high amount of Si interstitial atoms (Is), which dramatically increases the B diffusivity, is introduced. The introduction of voids in Si is a promising tool to control B transient enhanced diffusion (TED), because of their ability to capture Is. In this work the efficiency of a cavity band to reduce B TED is checked in silicon interstitial supersaturation conditions, obtained by high dose Si implantation. He is implanted either at 10 keV or at 50 keV with a fluence of 5 x 10"1"6 cm"-"2. Conventional techniques to introduce and activate the B (conventional ion implantation and rapid thermal annealing (RTA)) are applied in order to have a better control of the technological ...

2009-03-15

417

DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH  

Energy Technology Data Exchange (ETDEWEB)

Due to the increasingly stricter regulations for deep reduction of fuel sulfur content, development of new deep desulfurization processes for liquid transport fuels has become one of the major challenges to the refining industry and to the production of hydrocarbon fuels for fuel cell applications. The sulfur compounds in the current transport fuels corresponding to the S level of 350-500 ppm account for only about 0.12-0.25 wt % of the fuel. The conventional hydrotreating approaches will need to increase catalyst bed volume at high-temperature and high-pressure conditions for treating 100 % of the whole fuel in order to convert the fuel mass of less than 0.25 wt %. In the present study, we are exploring a novel adsorption process for desulfurization at low temperatures, which can effectively reduce the sulfur content in gasoline, jet fuel and diesel fuel at low investment and operating cost to meet the needs for ...

2001-09-01

418

Chemistry of transuranium elements and compounds  

International Nuclear Information System (INIS)

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

1986-05-01

419

A wirelessly powered and controlled device for optical neural control of freely-behaving animals.  

Science.gov (United States)

Optogenetics, the ability to use light to activate and silence specific neuron types within neural networks in vivo and in vitro, is revolutionizing neuroscientists' capacity to understand how defined neural circuit elements contribute to normal and pathological brain functions. Typically, awake behaving experiments are conducted by inserting an optical fiber into the brain, tethered to a remote laser, or by utilizing an implanted light-emitting diode (LED), tethered to a remote power source. A fully wireless system would enable chronic or longitudinal experiments where long duration tethering is impractical, and would also support high-throughput experimentation. However, the high power requirements of light sources (LEDs, lasers), especially in the context of the extended illumination periods often desired in experiments, precludes battery-powered approaches from being widely applicable. We have developed a headborne device weighing 2 g ...

2011-06-23

420

Mesozoic Era of relativistic heavy ion physics and beyond.  

Science.gov (United States)

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

1994-01-01

421

Breaking the 1000-gene barrier for Mimivirus using ultra-deep genome and transcriptome sequencing  

UK PubMed Central (United Kingdom)

BackgroundMimivirus, a giant dsDNA virus infecting Acanthamoeba, is the prototype of the mimiviridae family, the latest addition to the family of the nucleocytoplasmic...Full Text Available

422

PET/MRI hybrid imaging: devices and initial results  

International Nuclear Information System (INIS)

The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest PET/MRI developments use solid-state light detectors that can be operated even at high magnetic fields. Initial pilot studies with ...

2008-06-01

423

NGC 2770 - a supernova Ib factory?  

CERN Document Server

NGC 2770 has been the host of three supernovae of Type Ib during the last 10 years, SN 1999eh, SN 2007uy and SN 2008D. SN 2008D attracted special attention due to the serendipitous discovery of an associated X-ray transient. In this paper, we study the properties of NGC 2770 and specifically the three SN sites to investigate whether this galaxy is in any way peculiar to cause a high frequency of SNe Ib. We model the global SED of the galaxy from broadband data and derive a star-formation and SN rate comparable to the values of the Milky Way. We further study the galaxy using longslit spectroscopy covering the major axis and the three SN sites. From the spectroscopic study we find subsolar metallicities for the SN sites, a high extinction and a moderate star-formation rate. In a high resolution spectrum, we also detect diffuse interstellar bands in the line-of-sight towards SN 2008. A comparison of NGC ...

2008-01-01

424

An accurate high-speed single-electron quantum dot pump  

International Nuclear Information System (INIS)

Using standard microfabrication techniques, it is now possible to construct devices that appear to reliably manipulate electrons one at a time. These devices have potential use as building blocks in quantum computing devices, or as a standard of electrical current derived only from a frequency and the fundamental charge. To date, the error rate in semiconductor 'tuneable-barrier' pump devices, those which show most promise for high-frequency operation, have not been tested in detail. We present high-accuracy measurements of the current from an etched GaAs quantum dot pump, operated at zero source-drain bias voltage with a single ac-modulated gate at 340 MHz driving the pump cycle. By comparison with a reference current derived from primary standards, we show that the electron transfer accuracy is better than 15 parts per million. High-resolution studies of the dependence of the pump current on the quantum dot tuning ...

2010-07-01

425

Cerenkov ring imaging and spectroscopy of charged KSTAR interactions at 11 GeV/c  

Energy Technology Data Exchange (ETDEWEB)

The physics and technology of this new Cerenkov detector are discussed, including materials studies, construction techniques, and resolution measurements. Sources of resolution error are individually identified and measured where possible. The results of all studied indicate that the measurement resolution is understood. This work has led to the adoption of a large scale ring imaging detector as part of a new high energy physics spectrometer, the SLD, at the Stanford Linear Accelerator Center. Results from an amplitude analysis of strange meson final states in K/sup /minus//p ..-->.. /ovr K/sub 0//..pi../sup /minus//p interactions are presented. The data derive from a 4 event/nb exposure of the LASS (large Aperture Superconducting Solenoid) spectrometer to an 11 GeV/c K/sup /minus// beam. The data sample consists of /approximately/100,000 vents distributed over the Dalitz plot of the channel. The ...

1988-11-01

426

"Eztrack": A single-vehicle deterministic tracking algorithm  

Energy Technology Data Exchange (ETDEWEB)

A variety of surveillance operations require the ability to track vehicles over a long period of time using sequences of images taken from a camera mounted on an airborne or similar platform. In order to be able to see and track a vehicle for any length of time, either a persistent surveillance imager is needed that can image wide fields of view over a long time-span or a highly maneuverable smaller field-of-view imager is needed that can follow the vehicle of interest. The algorithm described here was designed for the persistence surveillance case. In turns out that most vehicle tracking algorithms described in the literature[1,2,3,4] are designed for higher frame rates (> 5 FPS) and relatively short ground sampling distances (GSD) and resolutions ({approx} few cm to a couple tens of cm). But for our datasets, we are restricted to lower resolutions and GSD's ({ge}0.5 m) and limited frame-rates ({le}2.0 Hz). ...

2007-12-20

427

Migration of strontium in the food chain of plants, animals and man - problems and risks  

International Nuclear Information System (INIS)

The aims of investigation were to follow the Sr transport in the food chain from the flora to the fauna and humans, and its dependence on the geological origin og the plant site, industrial emissions, the age and site of plants, the part of plant used for nutrition and the strontium content in the drinking water, to determine the Sr intake of humans with the help of the duplicate method, and to estimate the apparent absorption rate and balance of strontium depending on of the form of diet (mixed or ovolactovegetarian), sex, season, age, region (geological origin of the living space) and method of intake measurement (duplicate or basket method). Strontium, an ultra trace element widespread in the earth's crust, is not essential and only mildly toxic for plants, animals and man according to current knowledge. The biological essentiality of Sr has not been investigated yet. Amoeba species living in sea water use Sr for the formation of their skeleton instead of Ca. ...

2008-10-15

428

Zone mapping application for precision-farming: a decision support tool for variable rate application  

British Library Electronic Table of Contents (United Kingdom)

A web-based decision support tool, zone mapping application for precision farming (ZoneMAP, External Reference Not Shown ), has been developed to automatically determine the optimal number of management zones and delineate them using satellite imagery and field data provided by users. Application rates, such as of fertilizer, can be prescribed for each zone and downloaded in a variety of formats to ensure compatibility with GPS-enabled farming equipment. ZoneMAP is linked to Digital Northern Great Plains, a web-based application which hosts an archive of satellite imagery, as well as high resolution imagery from airborne sensors. Management zones created by ZoneMAP mapped natural variation of the soil organic matter and other nutrients relatively well and were consistent with zone maps cre...

2010-01-01

429

Two-step template-free route for synthesis of TiO2 hollow spheres  

British Library Electronic Table of Contents (United Kingdom)

The TiO2 hollow microspheres were prepared by microwave-assisted solvothermal treatment without template. The morphology and the phase of TiO2 hollow microspheres were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), and BET surface areas. The results show that the particles have hollow structures and the shell was covered by nanocrystals and have higher specific surface area. The possible formation mechanism of hollow TiO2 spherical structures has simply been proposed. The activity was evaluated by the photocatalytic degradation of methyl orange (MO). The results show that the particles having specific surface area show higher photocatalytic activity. It can be attribute to the doped ...

2011-01-01

430

Two-photon calcium imaging from head-fixed Drosophila during optomotor walking behavior  

British Library Electronic Table of Contents (United Kingdom)

Drosophila melanogaster is a model organism rich in genetic tools to manipulate and identify neural circuits involved in specific behaviors. Here we present a technique for two-photon calcium imaging in the central brain of head-fixed Drosophila walking on an air-supported ball. The ball's motion is tracked at high resolution and can be treated as a proxy for the fly's own movements. We used the genetically encoded calcium sensor, GCaMP3.0, to record from important elements of the motion-processing pathway, the horizontal-system lobula plate tangential cells (LPTCs) in the fly optic lobe. We presented motion stimuli to the tethered fly and found that calcium transients in horizontal-system neurons correlated with robust optomotor behavior during walking. Our technique allows both behavior ...

2010-01-01

431

Tunable single-wavelength semiconductor lasers  

Energy Technology Data Exchange (ETDEWEB)

This dissertation deals with both the theoretical and the technological aspects of monolithic tunable lasers, and the experimental techniques for opto-electronic integration. In the theoretical part, the principles and limitations of wavelength tuning and spectral linewidth reduction in monolithic semiconductor lasers are described, with coupled distributed feedback-Fabry Perot (DFB-FP) lasers and long DFB lasers as examples. Stepwise tuning of wavelength over tens of nanometers and continuous tuning over the range of a mode spacing are shown to be possible. Spatial hole burning is found to affect the spectral linewidth of lasers involving strong active gratings. On the technological side, one of the major issues is the fabrication of flexible gratings. Direct-writing techniques, such as focused ion beam (FIB) implantation and e-beam lithography, provide the resolution, flexibility and accuracy that conventional holographic lithography lacks. The parasitic ...

1988-01-01

432

Transmission electron microscopy of undermined passive films on stainless steel  

Energy Technology Data Exchange (ETDEWEB)

A study has been made of the passive film remaining over pits on stainless steel using a high resolution transmission electron microscope. Type 305 stainless steel was passivated in a borate buffer solution and pitted in ferric chloride. Passive films formed at 0.2 V relative to a saturated calomel electrode were found to be amorphous. Films formed at higher potentials showed only broad diffraction rings. The passive film was found to cover a remnant lacy structure formed over pits passivated at 0.8 V. The metallic strands of the lace were roughly hemitubular in shape with the curved surface facing the center of the pit.

1999-06-01

433

Trabecular scaffolds created using micro CT guided fused deposition modeling  

British Library Electronic Table of Contents (United Kingdom)

Free form fabrication and high resolution imaging techniques enable the creation of biomimetic tissue engineering scaffolds. A 3D CAD model of canine trabecular bone was produced via micro CT and exported to a fused deposition modeler, to produce polybutylene terephthalate (PBT) trabeculated scaffolds and four other scaffold groups of varying pore structures. The five scaffold groups were divided into subgroups (n=6) and compression tested at two load rates (49?N/s and 294?N/s). Two groups were soaked in a 25??C saline solution for 7?days before compression testing. Micro CT was used to compare porosity, connectivity density, and trabecular separation of each scaffold type to a canine trabecular bone sample. At 49?N/s the dry trabecular scaffolds had a compressive stiffness of 4.94?1.19?MP...

2008-01-01

434

Three Dimensional Visualization for the Steam Injection into Water Pool using Electrical Resistance Tomography  

International Nuclear Information System (INIS)

The direct injection of steam into a water pool is a method of heat transfer used in many process industries. The amount of research in this area however is limited to the nuclear industry, with applications relating to reactor cooling systems. Electrical resistance tomography (ERT), a low cost, non-invasive and which has high temporal resolution characteristics, can be used as a visualization tool for the resistivity distribution for the steam injection into water pool such as IRWST. In this paper, three dimensional resistivity distribution of the process is obtained through ERT using iterative Gauss-Newton method. Numerical experiments are performed by assuming different resistive objects in the water pool. Numerical results show that ERT is successful in estimating the resistivity distribution for the injection of steam in the water pool

2010-10-01

435

Theoretical considerations for X-ray phase contrast mammography by Thomson source  

Energy Technology Data Exchange (ETDEWEB)

The advent, in the near future, of compact X-ray sources like Thomson Back-Scattering (TBS) will allow the clinical application of advanced X-ray imaging techniques, such as phase contrast, with higher sensitivity and lower impact in terms of dose delivery. In this work, we theoretically investigated the possibility of using such sources for phase contrast imaging of micro-calcifications included in a breast tissue. In our study we analyzed the phase and amplitude distribution of the TBS source and we showed that this source can be used for phase contrast imaging since the source coherence at the sample position is sufficiently high for achieving good contrast and micrometer spatial resolution. Indeed the spatial coherence of a TBS source is closer to that of a synchrotron radiation source, and much better than that of a laboratory source. Moreover, we showed the advantages of phase imaging with respect to standard absorption imaging, in the ...

2009-09-01

436

The unusual host galaxy of the BL Lac object PKS 1413+135  

CERN Document Server

The BL Lacertae object PKS 1413+135 is associated with a disk dominated galaxy which heavily absorbs the BL Lac nucleus at optical and X-ray wavelengths. It has been argued whether this galaxy is actually the host galaxy of PKS 1413+135 or whether the BL Lac is a background QSO, gravitationally lensed by the apparent host galaxy. We have obtained deep high resolution H-band images of this unusual BL Lac object using the UKIRT IRCAM3. Our observations show that the BL Lac nucleus is centered within < 0.05 arcsec of the galaxy. Based on this result we assess the probability for the lensing scenario and come to the conclusion that the disk galaxy is indeed the host of PKS 1413+135. The galaxy shows peanut-shaped isophotes, suggesting the presence of a central bar which is a common feature of AGN

1999-01-01

437

The similarity of twin brains  

International Nuclear Information System (INIS)

To test the assumption underlying every morphometric twin study that the brains of monozygotic twins are almost identical. Methods: High resolution MRI of the neurocranium of 26 monozygotic twin pairs were acquired and the volumes of 36 cerebral structures were measured. The same twins served as control group after rear-ranging them into non-related pairs of same sex and matching them for age, body height and body weight. Results: For most of the examined structures the correlations within the twins were significant (R = 0,97-0,59). Except for total forebrain volume the controls showed no significant similarity. Conclusions: For almost every measured cerebral structure the assumption, that significant similarities exist between healthy monozygotic twins is correct. Therefore discordant monozygotic twins represent an excellent sample when investigating cerebral correlates of neurologic and psychiatric disorders. (orig.)

2001-06-01

438

The radio jet in NGC 6251  

International Nuclear Information System (INIS)

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

439

The effects of physical activity, education, and body mass index on the aging brain  

British Library Electronic Table of Contents (United Kingdom)

Abstract Normal human aging is accompanied by progressive brain tissue loss and cognitive decline; however, several factors are thought to influence brain aging. We applied tensor-based morphometry to high-resolution brain MRI scans to determine whether educational level or physical activity was associated with brain tissue volumes in the elderly, particularly in regions susceptible to age-related atrophy. We mapped the 3D profile of brain volume differences in 226 healthy elderly subjects (130F/96M; 77.9 3.6 SD years) from the Cardiovascular Health Study-Cognition Study. Statistical maps revealed the 3D profile of brain regions whose volumes were associated with educational level and physical activity (based on leisure-time energy expenditure). After controlling for age, sex, and physical...

2011-01-01

440

The VOISE Algorithm: a Versatile Tool for Automatic Segmentation of Astronomical Images  

CERN Document Server

The auroras on Jupiter and Saturn can be studied with a high sensitivity and resolution by the Hubble Space Telescope (HST) ultraviolet (UV) and far-ultraviolet (FUV) Space Telescope spectrograph (STIS) and Advanced Camera for Surveys (ACS) instruments. We present results of automatic detection and segmentation of Jupiter's auroral emissions as observed by HST ACS instrument with VOronoi Image SEgmentation (VOISE). VOISE is a dynamic algorithm for partitioning the underlying pixel grid of an image into regions according to a prescribed homogeneity criterion. The algorithm consists of an iterative procedure that dynamically constructs a tessellation of the image plane based on a Voronoi Diagram, until the intensity of the underlying image within each region is classified as homogeneous. The computed tessellations allow the extraction of quantitative information about the auroral features such as mean intensity, latitudinal and longitudinal ...

2009-01-01

441

Testing measurements at horizontal channels of the MARIA reactor performed using neutron spectrometers; Pomiary testowe przy kanalach poziomych reaktora MARIA wykonane przy uzyciu spektrometrow neutronow  

Energy Technology Data Exchange (ETDEWEB)

By means of neutron diffraction, using the standard polycrystalline sample of Al{sub 2}O{sub 3}, measurements on three (of four spectrometers) already installed in the front of horizontal channels of MARIA reactor have been performed. Basing on these experiments as well as on activation measurements carried out earlier, the fluxes of monoenergetic neutrons have been estimated. These experiments allowed to determine (for a given geometry and kind of monochromators chosen) the resolution efficiency of instruments and high order contamination in the reflected beam. With the help of polycrystalline vanadium and TbBr{sub 3} sample, the possibility of studies using the inelastic scattering process have been tested. (author) 7 refs, 15 figs, 7 tabs

1997-12-31

442

Synthesis and characterization of Co-Ag core-shell nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

A micellar method has been used to prepare silver-coated cobalt (Co-Ag) nanoparticles. The synthesized particles have been deeply characterized by several methods, i.e., XRD, UV-Vis, TEM, XPS, and electrochemical techniques. There is every indication that the obtained particles show a truly core-shell structure. All the nanoparticles obtained under different conditions are in the size range 3-5 nm. High-resolution TEM (HRTEM), Fast Fourier Transformation (FFT), and Selected Area Electron Diffraction (SAED) indicated that the presence of hcp-Co and fcc-Ag, in which cobalt is located in the central area; meanwhile silver is at the edges of the nanoparticle. The absorption band of the Co-Ag colloid shifts to a longer wavelength and broadens relative to that of pure silver colloid. Voltammetric characterization allowed to determine the coverage of the cobalt core.

2010-08-15

443

Surgical navigation using audio feedback.  

Science.gov (United States)

Current medical visualization technology intended for positional guidance in surgical applications may only ever have limited utility in the operating room due to the preexisting visual requirements of surgical practice. Additionally, visual systems impose limits as a result of their high latency, poor image resolution, problems with stereopsis and physical strain upon the user. Audio technology is relatively unexamined in the broad range of available methodologies for medical devices. The potential to translate surgical instrument position into audio feedback presents a novel solution to the human factors and engineering problems faced by visual display technology because audio technology employs a rich and as yet unburdened sensory modality. We describe an experimental system we have developed for investigating this new interface design approach using commercially available hardware. PMID:10173065

1997-01-01

444

Subclinical interstitial lung involvement in rheumatic diseases. Correlations of high-resolution Computed Tomography patterns with functional and cytologic findings  

International Nuclear Information System (INIS)

The aims of this study were to quantify the severity and extent of subclinical interstitial lung disease as depicted on HRCT and to study the relationship between the patterns of lung disease quantified by HRCT and the functional parameters and bronchoalveolar lavage findings in patients with rheumatic diseases. The results confirm that HRCT is a sensitive tool in detecting interstitial lung disease in patients with rheumatic diseases with no signs and symptoms of pulmonary involvement. The relationship between the different HRCT patterns and bronchoalveolar lavage cell profiles can identify patients at higher risk of developing irreversible lung fibrosis. A long-term, prospective follow-up study is needed to determine whether these patients will develop over pulmonary disease.

1999-01-01

445

Studies on natural radioactivity of some egyptian building materials  

International Nuclear Information System (INIS)

Using high-resolution y-rays spectrometry, the natural radioactivity of 14 samples of natural and o manufactured Egyptian building materials have been investigated. The samples were collected from local market and construction sites. From the measured gamma-ray spectra, specific activities were determined. The radium equivalent activity in each sample was estimated. Radiological evaluations of these materials indicate that all materials meet the external gamma-ray dose limitation. Calculation of concentration indices by assuming a Markkanen room model is constructed from these materials, to find the excess gamma-ray dose taken over that received from the outdoors. The Austrian Standard ONORM S 5200 is used in testing the building materials.

2004-02-24

446

State analysis of sulfur in coal and coal fly ash by double-crystal X-ray fluorescence spectrometry  

Energy Technology Data Exchange (ETDEWEB)

Double-crystal high-resolution X-ray fluorescence spectrometry was applied to the state analysis of sulfur in coal and related fly ash. For total sulfur, a proportional relationship exists between fluorescence intensities and the analytical values obtained by the oxygen-combustion method. Two oxidation states of sulfur were identified by a least square curve fitting method, by assuming that the spectrum profile is identical for each sulfur state but the intensity and the position are different. Sulfur in coal mainly consists of S/sup 2 -/, whereas that in coal fly ash mainly consists of S/sup 6 +/. As much as 0.04-0.08% of S/sup 2 -/ remains in fly ash.

1983-01-01

447

Some properties of atomic beam produced by laser induced ablation of Li target  

International Nuclear Information System (INIS)

Pulsed atomic beams produced in vacuum by laser induced ablation from a lithium target are analyzed by laser induced fluorescence (LIF). The 1-mixing processes induced in the n = 9, 10 Li Rydberg states by collisions with CO_2 molecules illustrate the application of the method. Resolution is limited by the 1 mm diameter of the probe laser beam. Combining LIF and absorption measurements gives n_L_i as a function of time at various distances from the target surface. The investigation of the Li-C0_2 1-mixing process in a heat pipe oven proved impossible due to the high reactivity of Li with C0_2. This problem was solved by renewing the Li atoms at each laser shot. Values obtained for n = 9, n = 10 are k = 17 x 10"-"8 and 15 x 10"-"8 cc/sec, respectively.

448

Silver nanoparticles prepared by chemical reduction-protection method, and their application in electrically conductive silver nanopaste  

Energy Technology Data Exchange (ETDEWEB)

Ag nanoparticles were prepared in a water-phase system with a mixture of silver-ammonia complex, sodium borohydride, and lauric acid according to molar feed ratio of approximately 6:3:1. The mechanism of preparation and separation by chemical reduction-protection method was explored. The as-synthesized Ag nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-vis spectroscopy, respectively. It was found that the size of high purity Ag particles was ranging from 30 to 50 nm with slight agglomeration. In addition, the as-synthesized wet Ag nanoparticles were dispersed stably in organic vehicle to formulate electrically conductive nanopaste. Upon direct-written and sintered, the array pattern of the nanopaste with the resolution of about 30 {mu}m was achieved with the electrical resistivity in the order of magnitude of 10{sup -5} {Omega} cm.

2010-04-02

449

Silicate emission in Orion  

CERN Document Server

We present mid-infrared spectro-imagery and high-resolution spectroscopy ofthe Orion bar and of a region in the Orion nebula. These observations have beenobtained in the Guaranteed Time with the Circular Variable Filters of the ISOcamera (CAM-CVF) and with the Short Wavelength Spectrometer (SWS), on board theEuropean Infrared Space Observatory (ISO). Our data shows emission fromamorphous silicate grains from the entire HII region and around the isolatedO9.5V star Theta2 Ori A. The observed spectra can be reproduced by a mixture ofinterstellar silicate and carbon grains heated by the radiation of the hotstars present in the region. Crystalline silicates are also observed in theOrion nebula and suspected around Theta2 Ori A. They are probably ofinterstellar origin. The ionization structure and the distribution of thecarriers of the Aromatic Infrared Bands (AIBs) are briefly discussed on thebasis of the ISO observations.

2000-01-01

450

Satellite remote sensing of Spratly Islands using SAR  

British Library Electronic Table of Contents (United Kingdom)

Spratly Islands, located in the southern part of the South China Sea (SCS), consist of more than 100 small islands, coral reefs and banks. Remote sensing is the only way to obtain a synoptic view of all of the islands in such a large area. It has been demonstrated that satellite synthetic aperture radar (SAR) imagery is a very powerful tool for monitoring meso-scale and small-scale ocean processes in a large area. In this study, satellite SAR images were used to study the ocean environment in the area of Spratly Islands. The aim was to understand the capability of satellite remote sensing to monitor ocean processes and provide information for future field studies. Two sets of high-resolution European Remote Sensing satellite (ERS)-2 SAR images over the entire Spratly Islands area were coll...

2008-01-01

451

SZ polarisation as a probe of the intracluster medium  

CERN Document Server

We present high-resolution hydrodynamical simulations of the degree and direction of polarisation imprinted on the CMB by the Sunyaev-Zel'dovich effect in the the line of sight to massive galaxy clusters. We focus on two contributions which contribute most of the induced CMB polarisation in addition to the intrinsic CMB quadrupole: the radiation quadrupole seen by electrons due to their own velocity in the plane normal to the line of sight, and the radiation quadrupole due to the thermal Sunyaev-Zel'dovich effect, which is generated by a previous scattering elsewhere in the cores of the local and nearby clusters. We show that inside the virial radius of a massive cluster, this latter effect, although being second order in the optical depth, can reach the level of the former effect. These two effects can, respectively, constrain the projected tangential velocity and inner density profile of the gas, if they can be separated with multi-frequency observations. As the ...

2004-01-01

452

SSRM characterisation of FIB induced damage in silicon  

International Nuclear Information System (INIS)

Scanning spreading resistance microscopy (SSRM) has been applied to study focused ion beam (FIB) induced damage in silicon in dependence on ion irradiation doses from 10"1"2 cm"-"2 to 2#centre dot#10"1"6 cm"-"2. Starting from the lowest dose, SSRM detects increasing spreading resistance (SR) with increasing dose. For doses from 2#centre dot#10"1"3 cm"-"2 to 4#centre dot#10"1"4 cm"-"2, a slight decrease of SR is measured whereas for higher doses SR again slightly increases. The results are explained by physical effects like decreased carrier mobility due to increased scattering, amorphisation of silicon and precipitation of implanted Ga ions. The results clearly prove that SSRM is well suited for the fast detection of ion beam induced damage with high lateral resolution.

2008-03-01

453

Results from a Prototype Chicane-Based Energy Spectrometer for a Linear Collider  

Energy Technology Data Exchange (ETDEWEB)

The International Linear Collider (ILC) and other proposed high energy e{sup +}e{sup -} machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 10{sup -4}. This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006-2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5 {center_dot} 10{sup -4} was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance.

2011-02-28

454

Reconstructions of archaeological contexts in OpenGl environments; Intelligenza artificiale per i beni culturali e le biblioteche digitali. Atti del Workshop  

Energy Technology Data Exchange (ETDEWEB)

DVR project concerns the creation of a virtual reality OpenGL system for desktop applications in archaeology. The main goal is the creation of a 3D information system using the real time interaction of OpenGL environments. The first case study implemented is the Vettii House, one of the most important and outstanding monuments in Pompei. The virtual reconstruction of these architectural models is based on very detailed photogrammetric surveys and it is connected with information layers and archaeometric data-bases regarding the state of conservation of walls, structures and any type of materials of the monument. A full 3D interface characterizes the system, comprising a high resolution texturing with detailed volumetric and geometric data. Finally, for the future, the project plans to fit the system for scientific and end users through the installation of stations on site.

2001-07-01

455

Reactions of the inner surface of carbon nanotubes and nanoprotrusion processes imaged at the atomic scale  

British Library Electronic Table of Contents (United Kingdom)

Although the outer surface of single-walled carbon nanotubes (atomically thin cylinders of carbon) can be involved in a wide range of chemical reactions, it is generally thought that the interior surface of nanotubes is unreactive. In this study, we show that in the presence of catalytically active atoms of rhenium inserted into nanotubes, the nanotube sidewall can be engaged in chemical reactions from the inside. Aberration-corrected high-resolution transmission electron microscopy operated at 80?keV allows visualization of the formation of nanometre-sized hollow protrusions on the nanotube sidewall at the atomic level in real time at ambient temperature. Our direct observations and theoretical modelling demonstrate that the nanoprotrusions are formed in three stages: (i) metal-assisted d...

2011-01-01

456

Rapid Sampling of Individual Organic Aerosol Species in Ambient Air with the Photoionization Aerosol Mass Spectrometer  

British Library Electronic Table of Contents (United Kingdom)

Analytical methods developed to sample and characterize ambient organic aerosols often face the trade-off between long sampling times and the loss of detailed information regarding specific chemical species present. In the work presented here, high-time resolution ambient measurements (3.5 minutes) are achieved by using the Photoionization Aerosol Mass Spectrometer (PIAMS) in conjunction with the mini-Versatile Aerosol Concentration Enrichment System (m-VACES). Aerosol sampling took place for one week at State of Delaware Air Quality Monitoring Site in Wilmington, Delaware in June 2006. The soft, universal ionization scheme of PIAMS allows for identification of various chemical compounds by a signature ion, often the molecular ion. Meteorological data was used to link some species, such as...

2008-01-01

457

Radiative corrections to the atomic levels in a periodic electromagnetic field  

Energy Technology Data Exchange (ETDEWEB)

The influence of a periodic electromagnetic field on the radiative corrections to the atomic energy levels is studied for the case of ''strong fields'' for which the interaction between the atom and field is of the order or greater than the radiative effects. The analysis is carried out on the basis of the Schwinger-Dirac equation for the propagation function of a bound electron in the field and on the basis of the density matrix in the Furry representation. It is shown that in the strong field approximation the radiative shifts and widths are manifest as radiative corrections to the quasi-energies. In super-high resolution experiments intensity effects in the radiative corrections to the atomic levels are obtained in the case of single-photon resonance. Some multiphoton processes are condidered by taking into account the effect of the field on the radiative structure of the levels.

1982-12-01

458

Pulsed Radiofrequency Ablation for Residual and Phantom Limb Pain: A Case Series  

British Library Electronic Table of Contents (United Kingdom)

Abstract Residual limb pain (RLP) and phantom limb pain (PLP) can be debilitating and can prevent functional gains following amputation. High correlations have been reported between RLP and the stump neuromas following amputation. Many treatment methods including physical therapy, medications, and interventions, have been used with limited success. Pulsed radiofrequency ablation (PRFA) has shown promise in treating neuropathic pain because of the inhibition of evoked synaptic activity. We present 4 amputees who were treated with PRFA after failing conservative management for their RLP and PLP. All 4 patients underwent PRFA and demonstrated at least 80% relief of RLP for over 6 months. One patient reported a complete resolution of phantom sensation while another patient had significantly de...

2010-01-01

459

Pitting corrosion of stainless steels; Lochkorrosion an nichtrostenden Staehlen  

Energy Technology Data Exchange (ETDEWEB)

Stainless steels can get pitting corrosion in halide containing solution, which make them a big risk in industrial production. Many investigations were made in the past in order to understand processes involved in pitting corrosion, pit initiation and pit growth. Results about the influence of alloying elements, their contents, the state of the structure, the condition of the surface, the content of chloride, the temperature, the pH-value, the velocity of flow and of the oxidizer on the chloride induced pitting corrosion of passive stainless steels are presented. Electrochemical measurements and the application of surface analytical methods (SEM, SAM, XPS) with high lateral resolution are carried out. A part of the samples received a diffusion annealing in order to obtain reproducible results. Pitting Resistance Equivalents (PRE) - Pitting Index - with different multipliers are given and discussed critical. An electrochemical method for ...

1996-01-01

460

Photosensitivity and imaging characteristics of ion-implanted PLZT ceramics  

International Nuclear Information System (INIS)

We reported in previous papers that both the near-uv and the visible photosensitivities of ferroelectric-phase PLZT (lead lanthanum zirconate titanate) ceramics are increased by as much as four orders of magnitude by ion implantation or a combination of thermal diffusion of Al and ion implantation. New results are presented here on high-energy (1 MeV) implants of Al and Ni and coimplants of Al + Ne and Ni + Ne, and these results are compared with earlier 500 keV implants of Al and Cr and coimplants of Al + Ne and Cr + Ne as surface modification techniques for increasing the visible photosensitivity of PLZT. The important role of grain size in determining optimum contrast and resolution of stored optical information is described in terms of new experimental results.

1985-08-12

461

Pharmaceutical applications of non-linear imaging  

British Library Electronic Table of Contents (United Kingdom)

Non-linear optics encompasses a range of optical phenomena, including two- and three-photon fluorescence, second harmonic generation (SHG), sum frequency generation (SFG), difference frequency generation (DFG), third harmonic generation (THG), coherent anti-Stokes Raman scattering (CARS), and stimulated Raman scattering (SRS). The combined advantages of using these phenomena for imaging complex pharmaceutical systems include chemical and structural specificities, high optical spatial and temporal resolutions, no requirement for labels, and the ability to image in an aqueous environment. These features make such imaging well suited for a wide range of pharmaceutical and biopharmaceutical investigations, including material and dosage form characterisation, dosage form digestion and drug rele...

2011-01-01

462

Parametric study of pulsed thermal bumps in supersonic boundary layer  

British Library Electronic Table of Contents (United Kingdom)

A three-dimensional numerical study is performed to explore the effect of pulsed spanwise-periodic surface thermal perturbation (also denoted as thermal bump) in a Mach 1.5 flat plate laminar boundary layer. A high-resolution upwind-biased Roe method is used with the compressive Van Leer harmonic limiter on a suitably refined mesh. The dependence of flow stability characteristics on the variation of thermal bump geometry (shape and dimension) and pulsing properties (disturbance amplitude and frequency) is assessed. It is shown that the finite-span thermal bumps generate streamwise vortices. When the thermal bump is pulsed, vortex shedding is observed, and the streamwise vorticity grows with the downstream distance. Analysis of the integrated disturbance energy indicates that the streamwise...

2011-01-01

463

Oxygen dynamics in periphyton communities and associated effects on phosphorus release from lake sediments  

Energy Technology Data Exchange (ETDEWEB)

Periphyton is typically a heterogeneous assemblage of filamentous and single celled photoautotrophic and heterotrophic micoorganisms suspended in a mucopolysaccharide matrix which they produce. By definition, the assemblage is attached to a substratum such as rock, sediment, or plant in an aquatic environment. Microtechniques with high spatial and temporal resolution are required to define metabolic interactions among the heterotrophic and autotrophic constituents, and between periphyton and its environment. This study used oxygen sensitive microelectrodes with tip diameters of < 30 m to investigate the effects of photosynthesis and respiration on the oxygen dynamics of several diverse periphyton communities both in situ and in laboratory microcosms. A novel flow-through system that utilized TSP radiotracer and that permitted manipulation of the velocity, flushing rate, and oxygen concentration of overlying water was developed to investigate ...

1986-01-01

464

Nuclear structure studies via neutron interactions  

Energy Technology Data Exchange (ETDEWEB)

Research preformed consisted of: (1) publication of an experimental paper for the n + {sup 40}Ar high resolution total cross section and submission of a theoretical paper dealing with the prediction of the average parameters deduced from the the data; (2) preliminary R-matrix analysis of the neutron total cross section data for the n + {sup 208}Pb systems, up to an energy of 1.7 MeV; (3) completed the analysis of neutron total cross section of data for n + {sup 54}Fe up to energy of 500 keV, with j{sup {pi}} values confirmed, in most cases, by differential scattering data; (4) analysis of total cross section data for the n + {sup 88}Sr system up to an energy of 175 keV; (5) development of a graphical interface for the code RFUNC, used to calculate the differential scattering cross sections, for comparison with measurements.

1991-03-01

465

New 88Sr(n,g)Astrophysical Reaction Rate from Resonance Analysis of New High-Resolution Neutron Capture and Transmission Data  

Science.gov (United States)

Because of its small cross section, the 88Sr(n,g) reaction is an important bottleneck during s-process nucleosynthesis. Hence, an accurate determination of this rate is needed to better constrain the neutron exposure in s-process models and to more fully exploit the recently discovered isotopic anomalies in certain meteorites. We have completed the resonance analysis of our new and improved measurements of the neutron capture and total cross sections for 88Sr made at the Oak Ridge Electron Linear Accelerator (ORELA). We describe our experimental procedures and resonance analysis, compare our results to previous data, and discuss their astrophysical impact.

1999-08-30

466

Neutrino cross sections with the MINER?A Experiment  

British Library Electronic Table of Contents (United Kingdom)

MINER?A is a high resolution, fully active detector designed to study neutrino interactions on nuclei in the NuMI beam at Fermi National Accelerator Laboratory. The active volume of the detector consists of 3 tons of plastic scintillator and includes embedded targets of 4He, C, H2O, Fe and Pb. The MINER?A collaboration expects to perform precision, A-dependent neutrino cross section measurements in the 1?10 GeV region, measure the axial form factor, and study nuclear shadowing of F2, quark-hadron duality and coherent pion production, among other topics. MINER?A began data taking in the fall of 2009. This paper describes the MINER?A experiment and provides an overview of the physics objectives along with estimated uncertainties of the measurements and the tentative projected schedule of dat...

2011-01-01

467

Monitoring environmental impacts of surface coal mining  

Energy Technology Data Exchange (ETDEWEB)

Coal mining generates a number of significant environmental impacts. Due to its synoptic coverage and repetitive data acquisition capabilities, remote sensing has been extensively used to monitor effects of surface mining. Availability of low cost and high resolution data in recent years has focused increased attention on the use of satellite data for monitoring surface mining activity. This article presents an overview of some of the important studies that have used satellite and airborne remote sensing data to assess environmental impacts of coal mining and to monitor reclamation activities. Detection and delineation of subsurface coal mine fires using remotely-sensed thermal data is also briefly discussed. The utility of interfacing remote sensing and Geographic Information Systems for effective environmental management of mining areas has been emphasized.

1993-04-01

468

Microstructural features in sintered Si_3N_4/SiC platelets systems  

International Nuclear Information System (INIS)

Analytical TEM and high resolution TEM were used in the microstructural characterization of hot-press sintered Si_3N_4-SiC platelets composites. The quantity of sintering additives, Er_2O_3 and AlN, was varied to produce different matrices, e. g. Si_3N_4, #beta#'+#alpha#'-Sialon and #alpha#'-Sialon. Detailed analysis of platelet-sialon matrix interfaces revealed the presence of AlN polytypoids. The polytypoids nucleate preferentially onto the (0001) plane of SiC and growth epitaxially in several ten nanometer layers contributing in this way to crystallize, partially, the matrix intergranular glass pockets contacting the platelets. Possible applications of the phenomena to microstructural control, grain boundary phase control and enhanced creep resistance are discussed. (orig.).

1993-10-04

469

Low-cycle fatigue behaviour and microstructure of copper and alpha-brass under biaxial load paths  

Energy Technology Data Exchange (ETDEWEB)

The low-cycle fatigue behaviour of copper and a-brass CuZn30 was investigated in uniaxial and biaxial tests. Planar biaxial fatigue tests were carried out using cruciform samples with proportional stain paths with and without phase shift between the two axes. Microcharacterisation was performed by electron microscopy as well as by high-resolution X-ray line profile analysis. The biaxial cyclic stress-strain curves show good agreement with the uniaxial ones using the von Mises equivalent strain hypothesis. The dislocation densities and microhardness values of the biaxial case, however, show significantly lower values compared to the uniaxial case at equivalent von Mises stresses.

2010-07-01

470

LDEF impact craters formed by carbon-rich impactors  

International Nuclear Information System (INIS)

Two small craters (number 74, 119 microns, and number 31, 158 microns in diameter) with depth to diameter ratios of about 0.59 and 0.8, respectively, were found in Al from the Long Duration Exposure Facility (LDEF) experiment tray A11EOOF. Both craters have residues concentrated in the crater bottoms, along the walls, and on top of the overturned rims. Low voltage scanning electron electron microscopy, Auger electron spectroscopy, time of flight secondary ion mass spectroscopy and energy dispersive x-ray spectroscopy were used to obtain high resolution imagery and elemental analysis. Analyses indicate that the impactor for both craters was carbon-rich, as the residues contain mostly C. Silicon, S, and F in low concentrations are present on the Al surface away from the craters and may be, in part, contaminants.

1991-06-01

471

Investigation of the local hardening effect produced by various low-Z materials in a Si/(Fe, Pb) electromagnetic calorimeter  

International Nuclear Information System (INIS)

The condition for obtaining a calorimetric response linear with energy for hadronic showers and an energy resolution that improves as the incident energy increases is the equalization of the electromagnetic (e) and the hadronic (#pi#) signal responses. This equalization is obtained by exploiting a local hardening effect realized through the insertion of low-Z thin plates between the high-Z absorbers and the active material in a hadronic calorimeter with silicon readout. This effect, which allows the reduction of the calorimeter response to the electromagnetic component of the incoming hadronic showers, has been investigated for different low-Z materials. The relevance of some aspects of this study to the radiation hardness of the calorimeters is also addressed. (orig.).

472

Interferometer Observations of Subparsec-scale Infrared Emission in the Nucleus of NGC 4151  

CERN Document Server

We report novel, high-angular resolution interferometric measurements that imply the near-infrared nuclear emission in NGC 4151 is unexpectedly compact. We have observed the nucleus of NGC 4151 at 2.2 microns using the two 10-meter Keck telescopes as an interferometer and find a marginally resolved source ~0.1 pc in diameter. Our measurements rule out models in which a majority of the K band nuclear emission is produced on scales larger than this size. The interpretation of our measurement most consistent with other observations is that the emission mainly originates directly in the central accretion disk. This implies that AGN unification models invoking hot, optically thick dust may not be applicable to NGC 4151.

2003-01-01

473

Infrared spectroscopy of rovibrational transitions of methyl radicals (CH3, CD3) in solid parahydrogen  

British Library Electronic Table of Contents (United Kingdom)

The n3 and n4 vibrational transitions of CH3 and CD3 isolated in solid parahydrogen were studied by high-resolution infrared spectroscopy. The radicals were produced by in situ UV photolysis of methyl iodides trapped in solid parahydrogen. The observed spectra showed clear rotational fine structures, which were subjected to further splitting due to the electrostatic field of solid parahydrogen. The molecular constants and crystal field parameters of the radicals in solid parahydrogen were determined by analyzing the spectral structures of the n3 and n4 transitions of CD3 by the crystal field theory. The rotational constants of the CD3 radical were found to be only a few percent smaller than those in the gas phase. The determined crystal field parameters indicated significant quantum effect...

2011-01-01

474

Influence of the strain-relaxation induced defect creation on the leakage current of embedded Si{sub 1-x}Ge{sub x} source/drain junctions  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to evaluate the role of the strain-relaxation processes on the leakage current of embedded SiGe S/D junctions. Current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured to further investigate the relaxation degree of embedded SiGe S/D junctions in the regime where partial relaxation by misfits dislocations is assumed, yielding a reduction of the leakage current density. Further, the impact of the ion implantation-related defects on the electrical performance is discussed. The analysis is complemented with structural characterization based on High Resolution Transmission Electron Microscopy (HRTEM) and Nomarski microscopy. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

2009-08-15

475

In situ ultrahigh vacuum transmission electron microscopy studies of palladium silicide island formation on silicon (111) 7x7 surface  

International Nuclear Information System (INIS)

Pd was deposited onto Si (111) 7x7 surface at approximately 700 K inside an ultrahigh vacuum transmission electron microscope. Plan-viewed transmission electron microscopy (TEM) observation indicated that the islands have two kinds of shapes, round and rectangular (one-dimensional) ones. In a diffraction pattern for the rectangular islands, extra spots along the <110> direction of the Si surface, spacing of which is 1/8 times as long as that of Si (220) spots, were seen. A high resolution TEM image showed the corresponding superstructure in the rectangular islands. In situ observation of the growing process of the rectangular islands showed repeat of introduction and relief of strains during the growth, suggesting that such superstructure would be constructed by stacking compositionally different phases or introducing defects so that the periodically maximized strain is relieved.

2003-01-22

476

IC chip stress during plastic package molding  

Energy Technology Data Exchange (ETDEWEB)

Approximately 95% of the world`s integrated chips are packaged using a hot, high pressure transfer molding process. The stress created by the flow of silica powder loaded epoxy can displace the fine bonding wires and can even distort the metalization patterns under the protective chip passivation layer. In this study the authors developed a technique to measure the mechanical stress over the surface of an integrated circuit during the molding process. A CMOS test chip with 25 diffused resistor stress sensors was applied to a commercial lead frame. Both compression and shear stresses were measured at all 25 locations on the surface of the chip every 50 milliseconds during molding. These measurements have a fine time and stress resolution which should allow comparison with computer simulation of the molding process, thus allowing optimization of both the manufacturing process and mold geometry.

1998-02-01

477

Hybrid Camera Surveillance System Using Robust Human Detection  

Science.gov (United States)

We propose a novel surveillance system that uses hybrid camera network. The system contains a panorama camera and PTZ cameras to take the wide range images and face images at high enough resolution for identification tasks. The robust human detection methods include robust background subtraction method (RRC), skin color segmentation and face tracking method. First, the system detects persons from a panorama image, and then the detailed face images are obtained with the PTZ cameras. The PTZ cameras can track the faces using the four directional features and the relaxation matching. In addition, the system has automatic camera position calibration feature. Thus, the user can use the system without any troublesome settings.

2007-01-01

478

Human cDNA mapping using fluorescence in situ hybridization  

Energy Technology Data Exchange (ETDEWEB)

Genetic mapping is approached using the techniques of high resolution fluorescence in situ hybridization (FISH). This technology and the results of its application are designed to rapidly generate whole genome as tool box of expressed sequence to speed the identification of human disease genes. The results of this study are intended to dovetail with and to link the results of existing technologies for creating backbone YAC and genetic maps. In the first eight months, this approach generated 60--80% of the expressed sequence map, the remainder expected to be derived through more long-term, labor-intensive, regional chromosomal gene searches or sequencing. The laboratory has made significant progress in the set-up phase, in mapping fetal and adult brain and other cDNAs, in testing a model system for directly linking genetic and physical maps using FISH with small fragments, in setting up a database, and in establishing the validity and throughput ...

1993-03-04

479

High-Resolution Optical Coherence Tomography Findings in Solar Maculopathy and the Differential Diagnosis of Outer Retinal Holes  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo characterize the morphology of outer retinal holes caused by solar maculopathy, using spectral-domain optical coherence tomography (SD-OCT). DesignThis study is an observational case series. MethodsThe SD-OCT findings of 3 patients (6 eyes) with chronic solar maculopathy are presented. ResultsSD-OCT demonstrates a characteristic appearance of partial-thickness hole(s) in the outer retina at the fovea. In 3 of 6 eyes, there is 1 hole directly beneath the umbo. In the remaining 3 eyes, there are multifocal holes spread across the fovea. Holes in more restricted layers, as had been previously reported with time-domain OCT, were not seen. In addition, advanced visualization of SD-OCT data demonstrates a hyperreflective ring around the outer retinal hole. ConclusionsSD-OCT can be used...

2011-01-01

480

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

CERN Document Server

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

2006-01-01

481

Finite element analysis of a scanning x-ray microscope micropositioning stage  

Energy Technology Data Exchange (ETDEWEB)

A micropositioning stage for use with an x-ray microscope has been developed to scan samples over a 100 {mu}m{times}100-{mu}m area with a resolution of 100 A. The stage employs flexure hinges driven by piezoelectric actuators to achieve this high positioning accuracy. Due to the severe geometry of the hinges, stresses and deflections are determined (via finite element methods) to ensure a credible design. Since the stage is to be used in a stepping capacity, natural frequencies are computed to identify resonant conditions which could potentially cause excessive deflections. The finite element models show that the stage responds like a discrete lumped-mass system for the lower modes, and a continuous system with flexural characteristics for the higher modes.

1992-01-01

482

Extrinsic allergic alveolitis induced by the yeast Debaryomyces hansenii.  

Science.gov (United States)

A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii. PMID:12449192

2002-11-01

483

Experimental parameterization of an energy function for the simulation of unfolded proteins  

DEFF Research Database (Denmark)

The determination of conformational preferences in unfolded and disordered proteins is an important challenge in structural biology. We here describe an algorithm to optimize energy functions for the simulation of unfolded proteins. The procedure is based on the maximum likelihood principle and employs a fast and efficient gradient descent method to find the set of parameters of the energy function that best explain the experimental data. We first validate the method by using synthetic reference data, and subsequently apply the algorithms to data from nuclear magnetic resonance spin-labeling experiments on the Delta 131 Delta fragment of Staphylococcal nuclease. A significant strength of the procedure that we present is that it directly uses experimental data to optimize the energy parameters, without relying on the availability of high resolution structures. The procedure is fully general and can be applied to a range of experimental data and ...

2008-01-01

484

Electron-microscopic study of amorphous boron structure  

Energy Technology Data Exchange (ETDEWEB)

Using the method of high resolution electron microscopy (HEM) the shape and structure of powder particles of elementary amorphous boron, prepared by plasmochemical reduction of boron trichloride by hydrogen before and after their heat treatment in vacuum of approximately 1 x 10 SPa at the temperature of approximately 800 deg C for 30 min, have been studied. It is established, that ultradispersed particles of amorphous boron present flat formations (discs) of stable configurations, composed of several icosahedrons (structural elements); their growth during heat treatment takes place first in habitus plane without far order formation, and then, after attaining the diameter of approximately 500 A, the process of three-dimensional crystallization starts, which leads to the formation of crystal lattice of boron US -rhombohedric modification.

1985-05-01

485

Effects of molecular mobility on high resolution solid state NMR spectra: model systems  

Energy Technology Data Exchange (ETDEWEB)

It is the intention of this paper to point to some of the problems due to molecular motion and to suggest a few solutions to those problems. A few examples will be presented of model systems which demonstrate the effects of motion on the NMR spectroscopy and a very qualitative example of severe spectral distortion in fulvic acids will be shown. In the following discussions we will use concepts derived from the oft repeated thermodynamic picture shown in figure 1. When dealing with a homogeneous, pure compound this picture is sufficient but in a heterogeneous mixture, it is likely that there will be different compounds and different domains all with slightly different versions of figure 1 with poor thermodynamic contact between them. Thus optimal conditions for cross polarization in one domain may be totally inappropriate for another. 59 refs., 10 figs.

1986-01-01

486

Disordered bcc γ-phase to δ-phase transformation in Zr-rich U-Zr alloy  

British Library Electronic Table of Contents (United Kingdom)

The transformation mechanism of hexagonal delta phase from the disordered bcc gamma phase has not been reported before in the Zr-rich U-Zr alloy system. With the help of X-ray diffraction, transmission electron microscopy (TEM) and high-resolution TEM analyses it was shown that the gamma to delta conversion takes place by the lattice collapse mechanism of omega transformation. It was also ascertained that a higher aging temperature or time promotes the growth of all four variants of the delta phase within a parent gamma grain. In addition, ab initio electronic structure calculations showed that the bcc to hexagonal transformation, involving partial ordering of the parent bcc phase followed by (111) plane collapse, is energetically favorable.

2011-01-01

487

Diffuse X-ray scattering study of sublattice ordering among group III atoms in In_0_._5Ga_0_._5P and In_0_._5Al_0_._5P  

International Nuclear Information System (INIS)

The intensity of superstructure reflections and associated diffuse scattering from In_0_._5Ga_0_._5P and In_0_._5Al_0_._5P epitaxic layers grown on (001) GaAs substrates was mapped in reciprocal space. The Warren-Cowley short-range-order parameters were obtained through the usual process for evaluating Fourier coefficients. Varying values for the correlation length in different directions indicate how group III atoms stack up in ordered states. The resultant structure with long-range order confirms the hypothesis made on the basis of electron diffraction and high-resolution transmission electron microscopy studies. (orig.).

488

Comparison of the results obtained by CALUX bioassay and GC-HRMS for different matrices  

Energy Technology Data Exchange (ETDEWEB)

The reference method used to analyse polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) is chromatography with high resolution mass spectrometry (GC-HRMS). It is interesting to check the suitability of screening methods that are faster and less expensive. Different matrices (milk, fish oil, chicken compound feed, pork tissue, chicken tissue, sepiolitic clay, whole egg and herring tissue) were analysed in the frame of the European project DIFFERENCE1. One of the aims of this project is to optimise screening methods. The CALUX bio-assay was one of the screening techniques used. This paper presents the extraction and purification methods used for the analyses. The CALUX results for dioxins and for dl-PCBs were compared to the corresponding GC-HRMS results.

2004-09-15

489

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

Science.gov (United States)

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

2010-09-01

490

Availability of essential trace elements in Ayurvedic Indian medicinal herbs using instrumental neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

Specific parts of several plants (fruits, leaves, stem, bark and roots) often used as medicines in the Indian Ayurvedic system have been analysed for 20 elements (As, Ba, Br, Ca, Cl, Co, Cr, Cu, Fe, K, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr and Zn) by employing instrumental neutron activation analysis (INAA). The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high resolution gamma ray spectrometry. Most of the medicinal herbs have been found to be rich in one or more of the elements under study. (Author).

1997-01-01

491

Assessment of periodic sub-diurnal Earth rotation variations at tidal frequencies through transformation of VLBI normal equation systems  

British Library Electronic Table of Contents (United Kingdom)

We present an empirical model for periodic variations of diurnal and sub-diurnal Earth rotation parameters (ERPs) that was derived based on the transformation of normal equation (NEQ) systems of Very Long Baseline Interferometry (VLBI) observing sessions. NEQ systems that contain highly resolved polar motion and UT1-TAI with a temporal resolution of 15?min were generated and then transformed to the coefficients of the tidal ERP model to be solved for. To investigate the quality of this model, comparisons with empirical models from the Global Positioning System (GPS), another VLBI model and the model adopted by the conventions of the International Earth Rotation and Reference Systems Service (IERS) were performed. The absolute coefficients of these models agree almost completely within 7.5?...

2011-01-01

492

Application of integrated high resolution sequence stratigraphy in the Jeanne d`Arc Basin, offshore Newfoundland - an illustration of the systems tracts within the Tithonian to Berriasian Hibernia Sequence  

Energy Technology Data Exchange (ETDEWEB)

The Jeanne d`Arc Basin is located 320 km offshore in the Grand Banks of Newfoundland. It is a Mesozoic failed-rift basin with recoverable oil reserves of about 2 billion barrels. Its huge Hibernia Field will be in production by late 1997. The basin has been reappraised using sequence stratigraphic concepts, and renewed exploration in the area is expected. The Upper Jurassic - Lower Cretaceous sedimentary accumulation in the Basin was formed by the extensional tectonics that created the North Atlantic Ocean. The sedimentary packages were placed in chronostratigraphic order by calibrating the biostratigraphy of the Oxfordian to Maastrichtian section to the detailed ammonite zonation from the North Sea.

1997-09-01

493

Advances in Modeling of Scanning Charged-Particle-Microscopy Images  

CERN Document Server

Modeling artificial scanning electron microscope (SEM) and scanning ion microscope images has recently become important. This is because of the need to provide repeatable images with a priori determined parameters. Modeled artificial images are highly useful in the evaluation of new imaging and metrological techniques, like image-sharpness calculation, or drift-corrected image composition (DCIC). Originally, the NIST-developed artificial image generator was designed only to produce the SEM images of gold-on-carbon resolution sample for image-sharpness evaluation. Since then, the new improved version of the software was written in C++ programming language and is in the Public Domain. The current version of the software can generate arbitrary samples, any drift function, and many other features. This work describes scanning in charged-particle microscopes, which is applied both in the artificial image generator and the DCIC technique. As an ...

2010-01-01

494

A new method of imaging particle tracks in solid state nuclear track detectors  

British Library Electronic Table of Contents (United Kingdom)

Summary Solid state nuclear track detectors are used to determine the concentration of a particles in the environment. The standard method for assessing exposed detectors involves 2D image analysis. However 3D imaging has the potential to provide additional information relating to angle as well as to differentiate clustered hit sequences and possibly energy of a particles but this could be time consuming. Here we describe a new method for rapid high-resolution 3D imaging of solid state nuclear track detectors. A `LEXT' OLS3100 confocal laser scanning microscope (Olympus Corporation, Tokyo, Japan) was used in confocal mode to successfully obtain 3D image data on four CR-39 plastic detectors. Three-dimensional visualization and image analysis enabled characterization of track features. This ...

2010-01-01

495

A new method of determining the inclination angle in interacting binaries  

CERN Document Server

We describe a method of determining the system parameters in non-eclipsing interacting binaries. We find that the extent to which an observer sees the shape of the Roche-lobe of the secondary star governs the amount of distortion of the absorption line profiles. The width and degree of asymmetry of the phase-resolved absorption line profiles show a characteristic shape, which depends primarily on the binary inclination and gravity darkening exponent. We show that, in principle, by obtaining high spectral and time resolution spectra of quiescent cataclysmic variables or low mass X-ray binaries in which the mass-losing star is visible, fitting the shape of absorption line profiles will allow one to determine not only the mass function of the binary, but also the binary inclination and hence the mass of the binary components.

1998-01-01

496

A modular neural network for direction-of-arrival estimation of two sources  

British Library Electronic Table of Contents (United Kingdom)

This work addresses the problem of estimating the direction-of-arrival (DOA) of two sources using an array of sensors. This problem is mostly useful in radar applications, where we have few targets at each range bin. Super-resolution algorithms, such as maximum likelihood (ML) estimation and multiple signal classification (MUSIC), have been applied to this problem, but the former involves high computation efforts, while the later has poor estimation performance for coherent sources. In this work, we propose a DOA estimation network, named RBF-AML, which combines the approximated ML (AML) estimator and a radial basis function (RBF) neural network (NN). In the proposed RBF-AML network, the entire two dimensional DOA space is divided into multiple sectors covered by RBF experts. The AML funct...

2011-01-01

497

A Danish decision-support GIS tool for management of urban air quality and human exposures  

Energy Technology Data Exchange (ETDEWEB)

A new prototype model system named AirGIS has been developed to support local authorities in air quality management for big Danish cities. The system is based on the Danish operational street pollution model (OSPM), technical and cadastral digital maps and Danish national administrative databases on buildings, cadastres and populations. It applies a geographic information system (GIS). AirGIS estimates ambient air pollution levels at high temporal and spatial resolutions. The model system enables mapping of traffic emissions, air quality levels and human exposures at residence addresses, at workplace addresses and in streets. Mapping and scenario results can be compared with air quality limits. Impact assessment of traffic air pollution abatement measures can also be carried out. (author)

2001-07-01