WorldWideScience
2

Prediction of the intramuscular fat content in loin muscle of pig carcasses by quantitative time-resolved ultrasound  

British Library Electronic Table of Contents (United Kingdom)

A novel method for non-destructive intramuscular fat (IMF) estimation via spectral ultrasound backscatter analysis of signals obtained from pig carcasses early post mortem is described. A commercial hand-held ultrasound device (center frequency: 2.7MHz) was modified to focus the sound beam to the longissimus muscle at the 2nd/3rd last rib. Time-resolved ultrasound backscatter signals of loin muscle were recorded 45minp.m. on 82 pig carcass sides. Backfat width (d"B"F=18.9+/-3.8mm) and muscle attenuation (@a"m"u"s"c"l"e=.77+/-.15dBMHz^-^1cm^-^1) were assessed from the measured pulse echo data. Other propagation properties of skin, backfat and muscle tissue obtained in a previous investigation were incorporated into the signal pre-processing to minimize parameter estimation artifacts. Spectr...

2012-01-01

3

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

4

Non-destructive testing of refractories, especially AZS materials, with ultrasound, microwaves and {gamma}-radiation  

Energy Technology Data Exchange (ETDEWEB)

In principle four different methods (ultrasound, microwaves, {gamma}-radiation and x-rays) are available for the non-destructive testing of refractories. Three of these methods, i.e. ultrasound, microwaves and {gamma}-radiation, are in use by different producers of AZS materials to carry out the quality control of their products. This paper will compare the three methods on the basis of the physical properties, present the existing devices, and show the advantages as well as the limits of the different methods. {gamma}-radiography, the oldest method in use, has one main disadvantage, which is the requirement of protection against radioactive radiation. Furthermore, while cracks and cavities can be detected with this method, structural changes can not be monitored. Therefore, the ultrasonic method was developed that allows to detect variations of porosity and grain size as well as cracks and voids when the ultrasonic ...

1995-08-01

5

In-situ measurement of epithelial tissue optical properties: Development and implementation of diffuse reflectance spectroscopy techniques  

Science.gov (United States)

Cancer is a severe threat to human health. Early detection is considered the best way to increase the chance for survival. While the traditional cancer detection method, biopsy, is invasive, noninvasive optical diagnostic techniques are revolutionizing the way that cancer is diagnosed. Reflectance spectroscopy is one of these optical spectroscopy techniques showing promise as a diagnostic tool for pre-cancer detection. When a neoplasia occurs in tissue, morphologic and biochemical changes happen in the tissue, which in turn results in the change of optical properties and reflectance spectroscopy. Therefore, a pre-cancer can be detected by extracting optical properties from reflectance spectroscopy. This dissertation described the construction of a fiberoptic based reflectance system and the development of a series of modeling studies. This research is aimed at ...

2009-01-01

6

Temperature and time-dependence of the elastic moduli of Pu and Pu-Ga alloys  

International Nuclear Information System (INIS)

In previous work, on cooling from 300 K to 10 K the elastic moduli for both #alpha#- and #delta#-Pu dropped 30%. This large change may reflect effects of 5f-electron localization. In this work, the elastic moduli at ambient temperature of several Pu-Ga alloys were measured using resonant ultrasound spectroscopy (RUS). The strong temperature dependence of the bulk and shear modulus and the temperature independence of Poisson's ratio was confirmed and the upper temperature limit for #alpha#-Pu was extended to 360 K. Measurements of the time dependence of the shear moduli of Pu and Pu-2.36 at.% Ga were determined with high precision as a function of time and temperature. Using a model for time dependence of point defects, we determined the exponential time constant at ambient temperature for such variations. The low temperature results are consistent with Fluss .

2007-10-11

7

A Method for Accurate in silico modeling of Ultrasound Transducer Arrays  

UK PubMed Central (United Kingdom)

This paper presents a new approach to improve the in silico modeling of ultrasound transducer arrays. While current simulation tools accurately predict the theoretical element...Full Text Available

2009-05-01

8

A comparison of truncated total least squares with Tikhonov regularization in imaging by ultrasound inverse scattering  

International Nuclear Information System (INIS)

For good image quality using ultrasound inverse scattering, one alternately solves the well-posed forward scattering equation for an estimated total field and the ill-posed inverse scattering equation for the desired object property function. In estimating the total field, error or noise contaminates the coefficients of both matrix and data of the inverse scattering equation. Previous work on ill-posed inverse ultrasonic scattering commonly used Tikhonov regularization, which considers error only in the data. The solution so obtained is not precise enough to reconstruct the quantitative internal structure of a large or high-contrast object. This paper adopts the truncated total least squares method, simultaneously considering error and noise on both sides of the inverse scattering equation, and compares it with the classical Tikhonov regularization. We show that it can substantially improve reconstruction fit and image quality when the inverse ...

2003-08-07

12

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

International Nuclear Information System (INIS)

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

2006-02-01

13

Reflectance, Optical Properties, and Stability of Molybdenum/Strontium and Molybdenum/Yttrium Multilayer Mirrors  

Energy Technology Data Exchange (ETDEWEB)

The motivation of this work is to develop high reflectance normal-incidence multilayer mirrors in the 8-12 nm wavelength region for applications in astronomy and extreme ultraviolet lithography. To achieve this goal, Mo/Sr and Mo/Y multilayers were studied. These multilayers were deposited with a UHV magnetron sputtering system and their reflectances were measured with synchrotron radiation. High normal-incidence reflectances of 23% at 8.8 nm, 40.8% at 9.4 nm, and 48.3% at 10.5 nm were achieved. However, the reflectance of Mo/Sr multilayers decreased rapidly after exposure to air. Attempts to use thin layers of carbon to passivate the surface of Mo/Sr multilayers were unsuccessful. Experimental results on the refractive index {tilde n} = 1-{delta} + i{beta} of yttrium and molybdenum in the 50-1300 eV energy region are reported in this work. This is the first time ever that values on the refractive index ...

2002-09-01

14

State-of-the-Art Survey of Ferrocement.  

Science.gov (United States)

From this literature study it was found that ferrocement is a composite material of superior mechanical properties when compared to reinforced concrete. This superiority is reflected in greater flexural crack strength, tensile strength, ductility, and imp...

1971-01-01

15

Development and Evaluation of a Reflective Solar Disinfection Pouch for Treatment of Drinking Water  

UK PubMed Central (United Kingdom)

A second-generation solar disinfection (SODIS) system (pouch) was constructed from food-grade, commercially available packaging materials selected to fully transmit and amplify the antimicrobial properties...Full Text Available

2004-04-01

16

Correlations between surface structure and catalytic activity/selectivity  

Energy Technology Data Exchange (ETDEWEB)

Work continued on the correlations of catalytic activity of metals and surface structure. Work is described in the following areas: CO oxidation on a Cu/Rh(100) Bimetallic catalysts; electronic properties of bimetallic surfaces; and reflection absorption spectroscopy of bimetallic surfaces. 5 figs. (CBS)

1990-11-01

17

Ultrasound diagnosis of cephalopagus conjoined twin pregnancy at 29 weeks  

UK PubMed Central (United Kingdom)

The authors report a case of a cephalopagus conjoined twin that was diagnosed at 29 weeks of gestation despite the mother having had two ultrasounds done previously. The fetus had one head and face,...Full Text Available

18

Targeted gene transfection from microbubbles into vascular smooth muscle cells using focused, ultrasound-mediated delivery  

UK PubMed Central (United Kingdom)

We investigate a method for gene delivery to vascular smooth muscle cells using ultrasound triggered delivery of plasmid DNA from electrostatically coupled cationic microbubbles. Microbubbles...Full Text Available

2010-09-01

19

Multi-focal optical-resolution photoacoustic microscopy in vivo  

UK PubMed Central (United Kingdom)

Although ultrasound arrays were exploited in photoacoustic imaging to improve imaging speed, ultrasound-array-based optical-resolution photoacoustic microscopy (OR-PAM) has never been achieved...Full Text Available

2011-04-01

20

Mid-trimester diagnosis of bladder neck obstruction by ultrasound and paracentesis.  

UK PubMed Central (United Kingdom)

A bladder neck obstruction was suspected after ultrasound investigation at 16 weeks' gestation. Evaluation of protein content in the amniotic fluid, fetal ascites, and fluid from the overdistended bladder...Full Text Available

1983-06-01

21

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

UK PubMed Central (United Kingdom)

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

2005-10-01

22

A new method to measure necrotic core and calcium content in coronary plaques using intravascular ultrasound radiofrequency-based analysis  

UK PubMed Central (United Kingdom)

Although previous intravascular ultrasound (IVUS) radiofrequency-based analysis data showed acceptable reproducibility for plaque composition, measurements are not easily obtained, particularly that...Full Text Available

2010-04-01

23

Effect of Sintering Atmosphere on the Microwave Dielectric Properties and Far-Infrared Reflectivity Spectra of the (Zr{sub 0.8}Sn{sub 0.2})TiO{sub 4} Ceramics  

Energy Technology Data Exchange (ETDEWEB)

Microwave dielectric properties and far-infrared reflectivity spectra of (Zr{sub 0.8}Sn{sub 0.2})TiO{sub 4} ceramics with 1.0mol.% Sb{sub 2}O{sub 5} or WO{sub 3} were investigated in the various sintering atmospheres. The Q{center_dot}f value of the specimens sintered in oxygen atmosphere was enhanced due to the decrease of lattice anharmonic interaction resulting from the decrease of oxygen vacancies, whereas the dielectric constants remained constant regardless of sintering atmosphere. The effects of the sintering atmosphere on the changes of ionic and electronic polarization and the intrinsic microwave losses of the specimens were investigated by using the infrared reflectivity spectra from 50 to 4000cm{sup -1}, which were evaluated using Kramers-Kronig analysis and classical oscillator model. The relative tendency of microwave dielectric properties of the specimens calculated from the ...

2000-02-01

25

Microwave absorption properties and infrared emissivities of ordered mesoporous C-TiO2 nanocomposites with crystalline framework  

International Nuclear Information System (INIS)

Ordered mesoporous C-TiO2 nanocomposites with crystalline framework were prepared by the evaporation-induced triconstituent co-assembly method. The products were characterized by XRD, TEM, N2 adsorption-desorption and TG. Their microwave absorption properties were investigated by mixing the product and epoxy resin. It is found that the peak with minimum reflection loss value moves to lower frequencies and the ordered mesoporous C-TiO2 nanocomposite possesses an excellent microwave absorbing property with the maximum reflection loss of -25.4 dB and the bandwidth lower than -10 dB is 6.6 GHz. The attenuation of microwave can be attributed to dielectric loss and their absorption mechanism is discussed in detail. The mesoporous C-TiO2 nanocomposites also exhibit a lower infrared emissivity in the wavelength from 8 to 14 ?m than that of TiO2-free powder. -- Graphical abstract: Ordered mesoporous C-TiO2 ...

2010-12-01

26

Eddy current testing of CFRP; New probes and techniques. Wirbelstrompruefung von Kohlefaser-Kompositen; Neue Sonden und Messverfahren  

Energy Technology Data Exchange (ETDEWEB)

Nondestructive inspection of carbon fibre-reinforced plastics (CRFP) using eddy current methods is based not only on the conductivity of the fibres. High frequencies (up to 10 MHz) give access to capacitive effects reflecting properties of the matrix. The paper presents a method using rotating eddy current probes to measure the anisotropic electrical properties. Potential applications of this method are the structural identification of laminates and the estimating of its degradation. (orig.)

1994-01-01

27

Experimental evaluation of angularly-variable fiber geometry for targeting depth-resolved reflectance from layered epithelial tissue phantoms  

Science.gov (United States)

The aim of the present study focuses on experimentally demonstrating the efficacy of using angularly-variable fiber geometry to achieve the desired tissue-layer selection and probing depths with the further objective of enhancing the sensitivity and specificity of spectral diagnosis in stratified architectures that resemble human cervical epithelia. The morphological and biochemical features of epithelial tissue vary in accordance with tissue depths; consequently, the accuracy of spectroscopic diagnosis of epithelial dysplasia may be enhanced by probing the optical properties of this tissue. When correlated to cellular dysplasia, layer-specific changes in tissue optical properties may be deciphered by reflectance spectroscopy coupled with angularly-variable fiber geometry. This study addresses the utility of using such angularly-variable fiber geometry for resolving spatially-specific spectral signatures of tissue ...

2007-03-01

28

Synthesis, characterization and optical properties of a high NIR reflecting yellow inorganic pigment: Mo"6"+ doped Y_2Ce_2O_7 as a cool colorant  

International Nuclear Information System (INIS)

Full text: Pigments possessing the ability to confer high solar reflectance have received considerable attention in recent years. The inorganic class of NIR reflective pigments are mainly metal oxides and are primarily employed in two applications: (i) visual camouflage and (ii) reducing heat build up. More than half of the solar radiation consists of near-infrared radiation (52%), the remaining being 43% visible light and 5% ultraviolet radiation. Over heating due to solar radiation negatively affects comfort in the built environment and contributes substantially to electrical consumption for air conditioning and release of green house gases. A pigment which has strong reflections in the NIR region (780-2500 nm) can be referred to as a 'cool' pigment. However, most of the NIR reflective inorganic pigments particularly yellow (eg. cadmium yellow, lead chromate, chrome titanate yellow etc.) contain toxic ...

2010-11-24

29

Structural, electronic and optical properties of ZnX and CdX compounds (X = Se, Te and S) under hydrostatic pressure  

International Nuclear Information System (INIS)

The structural, electronic and optical properties of ZnX and CdX (X = Se, Te and S) are studied using density functional theory by the Wien2k package. The energy band gap, real and imaginary parts of the dielectric function, energy loss function, optical absorption coefficient and reflectivity spectra of these compounds are calculated. The Engel-Vosko approach improves the energy band gaps of ZnX and CdX compounds. The calculated optical parameters are in good agreement with available experimental results, particularly in the Engel-Vosko approach. Furthermore the effect of hydrostatic pressure on the energy band gap, the real and imaginary parts of the dielectric function of these compounds is studied. The first and second order pressure coefficient for the energy band gaps, the static dielectric function and the static reflectivity spectra are calculated.

2010-09-03

30

Scaling method for fast Monte Carlo simulation of diffuse reflectance spectra from multilayered turbid media  

Science.gov (United States)

A scaling Monte Carlo method has been developed to calculate diffuse reflectance from multilayered media with a wide range of optical properties in the ultraviolet-visible wavelength range. This multilayered scaling method employs the photon trajectory information generated from a single baseline Monte Carlo simulation of a homogeneous medium to scale the exit distance and exit weight of photons for a new set of optical properties in the multilayered medium. The scaling method is particularly suited to simulating diffuse reflectance spectra or creating a Monte Carlo database to extract optical properties of layered media, both of which are demonstrated in this paper. Particularly, it was found that the root-mean-square error (RMSE) between scaled diffuse reflectance, for which the anisotropy factor and refractive index in the baseline simulation were, ...

2007-04-01

31

Transurethral Ultrasound Diffraction Tomography  

Science.gov (United States)

... [5] GT Gullberg, RH Huesman, DNG Roy, J. Qi and BW Reutter, Esti- mation of the parameter covariance matrix for a one-compartment cardiac ...

2007-03-01

32

NASA - Get (In) on NASA Innovation!  

Science.gov (United States)

Sep 19, 2011 ... (The whispering voice, on the other hand, was the latest in ultrasound directed audio technology from the firm Audio Spotlight.) The NASA ...

33

Evaluation of Peripheral Atherosclerosis: A Comparative Analysis of Angiography and Intravascular Ultrasound  

UK PubMed Central (United Kingdom)

ObjectiveAngiography remains a critical component for diagnostic imaging and therapeutic intervention in peripheral arterial disease (PAD). The goal of this study...Full Text Available

2010-04-01

34

Breast Cancer Treatment  

Medline Plus

... mammography or on ultrasound but not found on physical examination, we consider them non-palpable or not ... lot of this. We send every patient for physical therapy, no matter what type of reconstruction we ...

35

Effect of esters on lubricity of hydrotreated jet fuel  

Energy Technology Data Exchange (ETDEWEB)

The authors synthesized a number of esters of stearic acid with polyhydric alcohols and ran comparative tests on aliphatic alcohols to determine their effects on the antiwear properties of the fuel. They conclude that the differences in effectiveness in improving the lubricity by the use of aliphatic alcohols and the full and partial esters of polyhydric alcohols and stearic acid can be explained by the presence of hydroxyl and ester groups close to each other in partial esters. This is reflected in the higher polarity of the partial esters, a higher rate of adsorption, and a stronger bonding of the adsorbed layer to the metal surface.

1985-07-01

36

Domestic and industrial applications of microwaves; Les micro-ondes dans les applications domestiques et/ou industrielles  

Energy Technology Data Exchange (ETDEWEB)

In addition to their use in high-speed ovens, microwaves are also finding applications in industrial manufacture, quality control and storage - anywhere where the high-frequency transmission or reflection properties of a material can be exploited. Microwaves are also being used in medical applications for the characterization of certain type of tumours. They are also being used in research into ultrasonic cavitation. (authors) 5 refs.

1999-01-01

37

Electronic properties of thin Ni{sub 2}MnIn Heusler films  

Energy Technology Data Exchange (ETDEWEB)

The half-metallic Heusler alloy Ni{sub 2}MnIn is of high interest for use in spin electronics since at the Ni{sub 2}MnIn/InAs interface a spin polarization of 100% is predicted. We prepare high-quality thin films of 20-60nm thickness by co-evaporation and DC magnetron sputtering. Point-contact Andreev reflection spectroscopy yields a spin polarization of up to 54%. By spectral generalized magneto-optical ellipsometry, the dielectric and magneto-optical properties are determined and ferromagnetic behavior below the Curie temperature T{sub C}=318K is proved.

2005-04-15

38

Reflection tomography using finite element method ray tracing  

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. After subdividing subsurface into triangular element we shoot off the ray into subsurface by the Snell`s law. And then after taking the ray path which is similar to proper assumption we can calculate ...

1996-12-01

39

Spontaneous excitation of an accelerated atom in a spacetime with a reflecting plane boundary  

Science.gov (United States)

We study a two-level atom in interaction with a real massless scalar quantum field in a spacetime with a reflecting boundary. The presence of the boundary modifies the quantum fluctuations of the scalar field, which in turn modifies the radiative properties of atoms. We calculate the rate of change of the mean atomic energy of the atom for both inertial motion and uniform acceleration. It is found that the modifications induced by the presence of a boundary make the spontaneous radiation rate of an excited inertial atom oscillate near the boundary and this oscillatory behavior may offer a possible opportunity for experimental tests for geometrical (boundary) effects in flat spacetime. While for accelerated atoms, the transitions from ground states to excited states are found to be possible even in a vacuum due to changes in the vacuum fluctuations induced by both the presence of the boundary and the acceleration of atoms, and this can be ...

2005-09-15

40

MRI of the foetal brain  

International Nuclear Information System (INIS)

Ultrasound examinations for foetal brain abnormalities have been a part of the routine antenatal screening programme in the UK for many years. In utero brain magnetic resonance imaging (MRI) is now being used increasingly successfully to clarify abnormal ultrasound findings, often resulting in a change of diagnosis or treatment plan. Interpretation requires an understanding of foetal brain development, malformations and acquired diseases. In this paper we will outline the technique of foetal MRI, relevant aspects of brain development and provide illustrated examples of foetal brain pathology.

2007-04-01

41

Endoscopic Ultrasound Guided Fine Needle Aspiration Biopsy in Diagnosis of Pancreatic and Peripancreatic Lesions: A Single Center Experience in Korea  

UK PubMed Central (United Kingdom)

Background/AimsAlthough endoscopic ultrasound guided fine needle aspiration (EUS-FNA) has been introduced and its use has been increasing in Korea, there have not been many reports...Full Text Available

2009-06-01

42

Carotid plaque regression following 6-month statin therapy assessed by 3T cardiovascular magnetic resonance: comparison with ultrasound intima media thickness  

UK PubMed Central (United Kingdom)

BackgroundCardiovascular magnetic resonance (CMR) allows volumetric carotid plaque measurement that has advantage over 2-dimensional ultrasound (US) intima-media thickness (IMT)...Full Text Available

43

Bandgap properties of the indium sulfide thin-films grown by co-evaporation  

British Library Electronic Table of Contents (United Kingdom)

In the present study the optical properties of co-evaporated indium sulfide thin films are investigated. Before being optically characterized, the composition as well as the crystalline properties of the film have been checked with the help of energy dispersive spectroscopy (EDX) and X-Ray diffraction (XRD) analyses. The optical absorption coefficient ? of this indium sulfide film has been deduced from reflectivity R(?) and transmission T(?) measurements. The fit of the curve representing ?(h?) suggests that the ?-In2S3 has an indirect bandgap of 2.01?eV. Density functional theory (DFT) calculations are performed on this indium sulfide compound, using TB-LMTO code. Through these band structure investigations, an indirect bandgap is predicted as observed experimentally. The top of the valen...

2009-01-01

44

Amputee Independent Prosthesis Properties-A new model for description and measurement.  

Science.gov (United States)

A model is presented for describing the Amputee Independent Prosthesis Properties (AIPP) of complete assemblies of trans-tibial prosthetic components distal to the socket. This new AIPP model includes features of both lumped parameter and roll-over models and describes prosthesis properties that are of importance in stance phase, including prosthetic foot geometry, normal stiffness, shear stiffness, and damping (energy dissipation). Methods are described for measuring the parameters of the AIPP model using a custom test-rig, commercial load-cell, and a motion capture system. Example data are presented for five pylon angles reflecting the shank angles seen in normal gait. Through the inclusion of measured AIPP in future in-vivo studies comparing different prostheses more generic information, as opposed to product specific claims, will become more widely available to inform future designs, prescription, and alignment ...

2011-08-09

45

Reflection tomography using finite element method ray tracing  

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. Since the FEM (Finite Element Method) ray tracing we have developed goes well the inverse velocities structure, we can apply the inversion problem to complex geological model. This report consists of ...

1996-12-01

46

Equation of state of laser-shocked compressed iron; Equation d'etat du fer comprime par choc laser  

Energy Technology Data Exchange (ETDEWEB)

This thesis enters the field of highly compressed materials equation of state studies. In particular, it focuses on the case of laser shock compressed iron. This work indeed aims at getting to the conditions of the earth's core, comprising a solid inner core and a liquid outer core. The understanding of phenomena governing the core's thermodynamics and the geodynamic process requires the knowledge of iron melting line locus around the solid-liquid interface at 3.3 Mbar. Several experiments were performed to that extent. First, an absolute measurement of iron Hugoniot was obtained. Following is a study of partially released states of iron into a window material: lithium fluoride (LiF). This configuration enables direct access to compressed iron optical properties such as reflectivity and self-emission. Interface velocity measurement is dominated by compressed LiF optical properties and is used as a pressure ...

2004-01-01

47

Simulation-based training improves applied clinical placement of ultrasound-guided PICCs  

British Library Electronic Table of Contents (United Kingdom)

Purpose Skilled placement of peripherally inserted central catheters (PICC) has a profound impact on patient well-being and costs of care. The use of ultrasound-guided methods and prescribed training for cannulation skills are evidence-based practice recommendations. The purpose of this study was to compare two methods of PICC instruction on the acquisition of applied skills. Methods Residents were randomly assigned to one of two groups (N?=?16/16) of this blind-rater study and were trained to perform ultrasound-guided PICC cannulation using either simulation or apprenticeship methods. All residents were assessed placing a PICC in applied clinical patient care. Results Residents who completed simulation training had significantly better transfer of skills to applied clinical practice than ...

2011-01-01

48

Preparation of AgCl Nanoparticles@Ancient Textile with Antibacterial Activity under Ultrasound Irradiation  

British Library Electronic Table of Contents (United Kingdom)

The growth of silver chloride nanoparticles on ancient textile was achieved by sequential dipping steps in alternating bath of potassium chloride and silver nitrate under ultrasound irradiation. The effect of ultrasound irradiation and sequential dipping steps in growth of the AgCl nanoparticles has been studied. These systems depicted a decrease in the particles size accompanying a decrease in the sequential dipping steps. The samples were characterized with powder X-ray diffraction (XRD) and scanning electron microscopy. XRD analyses indicated that the prepared AgCl nanoparticles on fiber were crystalline. The textile samples containing AgCl nanoparticles were tested for their antibacterial efficacy against Escherichia coli and were found to possess significant antibacterial activity.

2011-01-01

49

First trimester measurements of nasal bone length using three-dimensional ultrasound  

British Library Electronic Table of Contents (United Kingdom)

Objectives To investigate the feasibility and reproducibility of measurements of nasal bone length using a three-dimensional (3D) ultrasound in the first trimester. Methods In a prospective study, 118 consecutive pregnant women attending for Down syndrome screening at 11-13 + 6 weeks were recruited. They had successful fetal nasal bone measurement by two-dimensional (2D) ultrasound by four operators. Three-dimensional volumes were recorded in the mid-sagittal plane of fetal profile by the fifth operator and examined using multiplanar techniques. Another independent investigator randomly compared his measurements with one of the four operators. Results In the subsequent 3D examination, the nasal bone length could be examined in 94 cases (79.7%). The mean difference between the 2D and 3D mea...

2009-01-01

50

Adenopathies in lung cancer: a comparison of pathology, Computed Tomography and endoscopic ultrasound findings  

International Nuclear Information System (INIS)

A prospective comparative study with pathology was performed to assess the clinical value of Computed Tomography (CT) and endoscopic ultrasound (EUS) for nodal staging in lung cancer. A total of 329 nodal stations were dissected or sampled and 755 lymph nodes were examined at histology. On a pre-station basis, CT had greater sensitivity (74%) than EUS (56%), but EUS was more specific (83% versus 93%). The accuracy rates of the two techniques were similar. In conclusion, endoscopic ultrasound should be part of a routine preoperative diagnostic approach to non-small-cell lung cancer., because of its high specificity. Results can be improved when EUS and CT are combined., which suggests that these imaging modalities should be used together in selected patients for the noninvasive staging of non-small-cell lung cancer to identify local lymphatic spread.

1999-01-01

51

Turbulent break-off flows  

Energy Technology Data Exchange (ETDEWEB)

Different calculated models are presented for turbulent break-off flows and their classification, reflecting the sequence of historical development. The study was done based on equations of viscous liquid of the Navier-Stokes type with development of special phenomenological models of turbulence which take into consideration real properties of the break-off flows based on simpler models of flow presented in the work. In order to calculate two-dimensional turbulent flows, a method of viscous-nonviscous interaction is used. It employs numerical solutions for nonviscous flow and integrated methods of calculating the dissipative region. This method can be extended for calculating the transonic break-off flows, and also break-off in an incompressible fluid when there is cavitation.

1982-01-01

52

Solar aircraft  

Energy Technology Data Exchange (ETDEWEB)

This invention is concerned with a solar energy system for propelling aircraft. Obtained are forces for aerodynamic lift and impetus. The lifted body had a transparent upper surface for the sun light, but black or reflecting for IR-radiation and high thermal insulation properties. Inside of the lifted body, the air temperature increases and is lifted by convection influence. The air resistance of this body is low in horizontal direction and higher in vertical position. The payload could be shifted, so that the positive or negative angle of the whole body can be selected. By this principal it is possible to transform the static lifting force in a dynamic impetus.

1981-07-30

53

RADSOLVER: a computer program for calculating spectrally-dependent radiative heat transfer in solar cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

RADSOLVER is a computer program which calculates the radiation energy transport in cavity type receivers having an arbitrary number of apertures through which collimated beams of solar radiation enter. In contrast to the common assumption of gray (or semi-gray) surfaces used in the modeling of radiation transport, RADSOLVER accounts for the wavelength-dependence of emission, absorption and reflection with a band model of the radiative properties. It is intended that this report serve both as an instruction manual for the use of the RADSOLVER code and a vehicle for presenting the underlying theory. Illustrative examples along with input and output are presented.

1981-09-01

54

Interplay between the ray and mode effects in electromagnetic behavior of small-size hemielliptic dielectric lenses  

CERN Document Server

Focusing and resonance properties of two-dimensional small-size hemielliptic lenses made of different materials are studied numerically in order to estimate the influence of internal reflections on the radiation characteristics of dielectric lens antennas. Accuracy of in-house made algorithms based on combination of geometrical and physical optics and FDTD in the analysis of optical and modal effects in the behavior of such lenses is tested by comparison with the exact solution obtained using the Muller boundary integral equations. The range of applicability for the approaches is discussed.

2010-01-01

55

Electron microscopy and X-ray diffraction study of AlN layers  

International Nuclear Information System (INIS)

AlN nanocrystalline layers and superstructures are used in the modern optoelectronic technology as reflecting mirrors in semiconductor layers. In the present work the properties of AlN films prepared by sputtering methods from an AlN target in reactive Ar + N plasma were investigated. The characterization was performed with HRTEM, SEM, glancing angle XRD and RBS methods. The present measurements confirmed the polycrystalline structure of AlN layers and enabled the evaluation of their grain size. The roughness and thickness of the layers were additionally determined by ellipsometric and profilometric measurements. (author)

2001-09-23

56

Determining top dead center in fired internal combustion engines by microwaves  

Energy Technology Data Exchange (ETDEWEB)

For the determination of top dead center (TDC) of a running engine a measuring system using microwaves was developed by AEG and Volkswagen AG. The measuring method utilizes the Doppler shift of the microwaves, which were reflected at the up and down moving piston, and the varying resonance properties of the combustion chamber. The system works with a frequency of 61.4 GHz and can be used as well for spark ignition as form compression ignition engines, particularly for direct injection engines. The output signal is symmetrical to TDC. For data acquisition and data processing, i.e. the calculation of the point of symmetry, the computer system FARES is used in a special assembly.

1986-01-01

57

Combining laser chemical processing and aerosol jet printing: a laboratory scale feasibility study  

British Library Electronic Table of Contents (United Kingdom)

Abstract First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high-efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti-reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two-step fine-line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright 2010 John Wiley & Sons, Ltd.

2011-01-01

58

Preliminary studies of tunnel interface response modeling using test data from underground storage facilities.  

Energy Technology Data Exchange (ETDEWEB)

In attempting to detect and map out underground facilities, whether they be large-scale hardened deeply-buried targets (HDBT's) or small-scale tunnels for clandestine border or perimeter crossing, seismic imaging using reflections from the tunnel interface has been seen as one of the better ways to both detect and delineate tunnels from the surface. The large seismic impedance contrast at the tunnel/rock boundary should provide a strong, distinguishable seismic response, but in practice, such strong indicators are often lacking. One explanation for the lack of a good seismic reflection at such a strong contrast boundary is that the damage caused by the tunneling itself creates a zone of altered seismic properties that significantly changes the nature of this boundary. This report examines existing geomechanical data that define the extent of an excavation damage zone around underground tunnels, and the potential ...

2010-11-01

59

Pore structure of volcanic clasts: Measurements of permeability and electrical conductivity  

British Library Electronic Table of Contents (United Kingdom)

The pore structure of volcanic clasts is examined using measurements of porosity, permeability, and electrical properties. Permeability varies by several orders of magnitude among volcanic clasts and does not depend solely upon porosity. Electrical property measurements of saturated volcanic samples illustrate the influence of pathway tortuosity and pore shape on permeability. For equivalent eruption conditions, silicic samples show higher tortuosities, smaller vesicle sizes, and lower permeabilities than mafic samples. These differences are largely due to variations in vesiculation and crystallization history. Differences between explosive and effusive samples reflect the relative ability of bubbles to form and maintain connected pathways during bubble expansion and collapse. Isotropic sa...

2009-01-01

60

Characterizing the time variability in magnetized neutrino--cooled accretion disks: signatures of the gamma-ray burst central engine  

CERN Document Server

The central engine of Gamma Ray Bursts is hidden from direct probing with photons mainly due to the high densities involved. Inferences on their properties are thus made from their cosmological setting, energetics, low-energy counterparts and variability. If GRBs are powered by hypercritical accretion onto compact objects, on small spatial scales the flow will exhibit fluctuations, which could in principle be reflected in the power output of the central engine and ultimately in the high energy prompt emission. Here we address this issue by characterizing the variability in neutrino cooled accretion flows through local shearing box simulations with magnetic fields, and then convolving them on a global scale with large scale dynamical simulations of accretion disks. The resulting signature is characteristic, and sensitive to the details of the cooling mechanism, providing in principle a discriminant for GRB central engine ...

2010-01-01

61

Ultrasound-Guided Three-In-One Nerve Block for Femur Fractures  

UK PubMed Central (United Kingdom)

Femur fractures typically affect elderly patients with multiple co-morbidities. Pain control can be difficult, requiring intensive nursing and physician care as elderly patients may manifest cardiovascular...Full Text Available

2010-09-01

62

Selective imaging of adherent targeted ultrasound contrast agents  

UK PubMed Central (United Kingdom)

The goal of ultrasonic molecular imaging is the detection of targeted contrast agents bound to receptors on endothelial cells. We propose imaging methods that can distinguish adherent microbubbles...Full Text Available

2007-04-21

63

PROGRESS AND PROBLEMS IN THE APPLICATION OF FOCUSED ULTRASOUND FOR BLOOD-BRAIN BARRIER DISRUPTION  

UK PubMed Central (United Kingdom)

Advances in neuroscience have resulted in the development of new diagnostic and therapeutic agents for potential use in the central nervous system (CNS). However, the ability to deliver the...Full Text Available

2008-08-01

64

Neoangiogenesis in early cervical cancer: Correlation between color Doppler findings and risk factors. A prospective observational study  

UK PubMed Central (United Kingdom)

BackgroundThe aim of the present article was to evaluate whether angiogenic parameters as assessed by transvaginal color Doppler ultrasound (TVCD) may predict those prognostic factors...Full Text Available

65

Measurement of the quadriceps femoris muscle using magnetic resonance and ultrasound imaging.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To define a method for measurement of the cross sectional area and volume of the quadriceps femoris muscle using magnetic resonance imaging (MRI) in conjunction with stereology, and to compare...Full Text Available

1997-03-01

66

Kaposi's sarcoma involving the thyroid in a patient with AIDS  

International Nuclear Information System (INIS)

A 30-year-old man with acquired immune deficiency syndrome (AIDS) and Kaposi's sarcoma had a palpable thyroid mass and cervical lymphadenopathy. Nuclear medicine and ultrasound scans revealed multiple thyroid nodules. Results of biopsy showed Kaposi's sarcoma metastatic to the thyroid.

67

Intravascular ultrasound to guide the management of intracoronary thrombus: a Case Report  

UK PubMed Central (United Kingdom)

Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction.We discuss the role of intravascular imaging to...Full Text Available

68

Endovascular surgery for peripheral arterial occlusive disease. A critical review.  

UK PubMed Central (United Kingdom)

Endovascular surgery is a new multidisciplinary field that applies the recently innovated techniques of angioscopy, intraluminal ultrasound, balloon angioplasty, laser, mechanical atherectomy, and stents....Full Text Available

1992-07-01

69

Efficacy of ultrasound-guided obturator nerve block in transurethral surgery  

UK PubMed Central (United Kingdom)

Background:During transurethral resection surgery (TUR), accidental stimulation of the obturator nerve can cause violent adductor contraction, leading to serious intraoperative...Full Text Available

2011-01-01

70

Assessment of the bone quality of black male athletes using calcaneal ultrasound: a cross-sectional study  

UK PubMed Central (United Kingdom)

BackgroundLifestyle, genetics and environmental factors are established determinants of bone density. We aimed to describe the bone characteristics of competitive top-ranked Nigerian...Full Text Available

71

A non-invasive technique for standing surgical repair of urinary bladder rupture in a post-partum mare: a case report  

UK PubMed Central (United Kingdom)

An 11-year-old mare presented 36 hours after foaling with a ruptured bladder. Uroperitoneum was diagnosed on ultrasound and from the creatinine concentration of the peritoneal fluid. Bladder endoscopy...Full Text Available

72

Pioglitazone does not affect vascular or inflammatory responses after endotoxemia in humans.  

Science.gov (United States)

PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal white blood cell flux, ...

2008-05-21

76

Status report on the development of a three-dimensional conceptual model for the Hanford Site unconfined aquifer system  

Energy Technology Data Exchange (ETDEWEB)

This report presents the status of development of a three-dimensional conceptual model for the unconfined aquifer system at Hanford. A conceptual model is needed to support development of a realistic three-dimensional numerical model for predicting ground-water flow and the transport of contaminants. The report focuses on developing a hydrogeologic framework, assessing available hydraulic property data, describing flow-system boundaries, and evaluating areal recharge and leakage. Geologic descriptions of samples obtained during well drilling were used to prepare cross sections that correlate relatively continuous layers. The layers were defined based on textural differences that are expected to reflect differences in hydraulic properties. Assigning hydraulic properties to the layers is a critical part of the conceptual model. Available hydraulic property data for the study area were ...

1992-11-01

77

Reliability of diagnostic imaging techniques in suspected acute appendicitis: proposed diagnostic protocol; Indicacion de las tecnicas de diagnostico por la imagen en la sospecha de apendicitis aguda: propuesta de protocolo diagnostico  

Energy Technology Data Exchange (ETDEWEB)

To study the utility of ultrasound and computed tomography (CT) in case of suspected appendicitis. To determine the diagnostic yield in terms of different clinical contexts and patient characteristics. to assess the costs and benefits of introducing these techniques and propose a protocol for their use. Negative appendectomies, complications and length of hospital stay in a group of 152 patients with suspected appendicitis who underwent ultrasound and CT were compared with those of 180 patients who underwent appendectomy during the same time period, but had not been selected for the first group: these patients costs for each group were calculated. In the first group, the diagnostic value of the clinical signs was also evaluated. The reliability of the clinical signs was limited, while the results with ultrasound and CT were excellent. The incidence of negative appendectomy was 9.6% in the study group and 12.2% in the ...

2001-07-01

78

Preparation of CaWO{sub 4}:Ln{sup 3+} SiO{sub 2} (Ln=Tb, Dy and Ho) nanoparticles by a combustion reaction and their optical properties  

Energy Technology Data Exchange (ETDEWEB)

The CaWO{sub 4}:Ln{sup 3+} SiO{sub 2} (Ln=Tb, Dy and Ho) nanoparticles were synthesized via a combustion process at 800 {sup o}C, using citric acid as chelating agent and fuel, ammonium nitrate as fuel, boric acid as flux material and silica as supports. The persistent phosphor nanoparticles were characterized by X-ray diffraction (XRD), reflectance UV-vis and fluorescence spectroscopy (PL) and transmission electron microscopy (TEM) techniques. XRD patterns indicated that crystalline calcium tungstate with scheelite structure was produced. The reflectance UV-vis spectra showed the broad absorption band of WO{sub 4}{sup 2-} groups and the PL spectra showed the WO{sub 4}{sup 2-} wide excitation band, broad emission band of WO{sub 4}{sup 2-} and characteristic emissions of Ln{sup 3+} ions. The average particle sizes were determined by TEM, which are about 50 nm.

2010-11-15

79

Preparation of CaWO_4:Ln"3"+ SiO_2 (Ln=Tb, Dy and Ho) nanoparticles by a combustion reaction and their optical properties  

International Nuclear Information System (INIS)

The CaWO_4:Ln"3"+ SiO_2 (Ln=Tb, Dy and Ho) nanoparticles were synthesized via a combustion process at 800 "oC, using citric acid as chelating agent and fuel, ammonium nitrate as fuel, boric acid as flux material and silica as supports. The persistent phosphor nanoparticles were characterized by X-ray diffraction (XRD), reflectance UV-vis and fluorescence spectroscopy (PL) and transmission electron microscopy (TEM) techniques. XRD patterns indicated that crystalline calcium tungstate with scheelite structure was produced. The reflectance UV-vis spectra showed the broad absorption band of WO_4"2"- groups and the PL spectra showed the WO_4"2"- wide excitation band, broad emission band of WO_4"2"- and characteristic emissions of Ln"3"+ ions. The average particle sizes were determined by TEM, which are about 50 nm.

2010-11-01

80

Photocatalytic self-cleaning properties of cellulosic fibers modified by nano-sized zinc oxide  

International Nuclear Information System (INIS)

Nano-sized zinc oxide was synthesized and deposited onto cellulosic fibers using the sol-gel process at ambient temperature. The prepared materials were characterized using several techniques including scanning electron microscopy, transmission electron microscopy, diffuse reflectance spectroscopy, X-ray diffraction and thermogravimetric analysis. X-ray diffraction studies of the ZnO-coated fiber indicate formation of the hexagonal crystal phase which was satisfactory crystallized on the fiber surface. The electron micrographs show formation of zinc oxide nanoparticles within 10-15 nm in size which have been homogeneously dispersed on the fiber surface. The prepared materials show significant photocatalytic self-cleaning activity, which was monitored by diffuse reflectance spectroscopy. The photoactivity was studied upon measuring the photodegradation of methylene blue and eosin yellowish under UV-Vis irradiation. The photocatalytic activity of ...

2011-03-31

81

Experimental study of the premixed combustion within the nonhomogeneous porous ceramic media  

Energy Technology Data Exchange (ETDEWEB)

An experimental investigation of premixed methane-air combustion within the one-dimensional porous ceramic burners for various burner configurations is presented. The burner is nonhomogeneous because of different pore size ceramic block used in different section of the burner. Therefore, the thermophysical and transport properties are nonuniform along the burner core length. The burners are constructed of partially stabilized zirconia. The CO and NO{sub x} emissions, flame speed, and flame stability are examined and compared at lean equivalence ratios for five different burner configurations. The sandwich-structured burner has very favorable flame stabilizing characteristic due to the radiation reflecting region. While the combustion proceeds at faster rate than other burner configurations, the radiation reflecting region and the exit surface have low temperature. Thus the NO{sub x} emission can be kept at the same low ...

1996-12-01

82

Copper and brass aged at open circuit potential in slightly alkaline solutions  

Energy Technology Data Exchange (ETDEWEB)

Surface oxide films were grown on 99.99% copper and brass (copper-zinc alloy, Cu77Zn21Al2) in 0.1 mol L{sup -1} borax solution at open circuit potential and were characterized using various experimental techniques. The composition of the passive films formed in situ on the different materials was studied using differential reflectance spectroscopy. The thickness of the oxide layers on copper and brass was compared by chronopotentiometric curves and potentiodynamic reductions. The electrical properties of each oxide were analyzed by means of electrochemical impedance spectroscopy. Their influence on the oxygen reduction reaction was also investigated using voltammetry hydrodynamic tools such as the rotating disk electrode. The results show that the incorporation of Zn to Cu in brass changes the composition and the thickness of the surface film. The films grown on brass tend to be thicker but less resistive and Zn compounds incorporate to the ...

2009-12-01

83

Study of structural and optical properties of sprayed WO{sub 3} thin films using enhanced characterization techniques along with the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this study, WO{sub 3} thin films were grown on glass substrates using an aqueous solution containing tungstate (NH{sub 4}){sub 2}WO{sub 4} as precursor. The substrate temperature incremented from 250 to 500 deg. C, by steps of 50 deg. C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at T{sub s} = 350 and 400 deg. C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400 deg. C were annealed in air for 2 h at 450 and 500 deg. C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T({lambda}) and reflectance ...

2009-11-13

84

Study of structural and optical properties of sprayed WO3 thin films using enhanced characterization techniques along with the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this study, WO3 thin films were grown on glass substrates using an aqueous solution containing tungstate (NH4)2WO4 as precursor. The substrate temperature incremented from 250 to 500 deg. C, by steps of 50 deg. C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at Ts = 350 and 400 deg. C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400 deg. C were annealed in air for 2 h at 450 and 500 deg. C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T(?) and reflectance R(?) spectra in 300-1800 nm domain. The ...

2009-11-13

85

Optical and electronic properties of Ag nanodots on Si(111)  

International Nuclear Information System (INIS)

Reflectance anisotropy spectroscopy (RAS) has been used, together with scanning tunnelling spectroscopy (STS), to investigate the optical and electronic properties of nanodots formed by depositing Ag on the Si(111)-3 x 1-Ag surface. One-dimensional (1D) arrays of nanodots were grown on a single-domain (3 x 1)-Ag surface and the anisotropic optical response in the 0.5-5 eV range measured by RAS. Aligned, elongated Ag islands were also grown on this surface to compare their properties with those of the nanodots. STS of the Ag islands showed distinct metallic behaviour, whereas the nanodots revealed a bandgap of #approx#0.6 eV, indicating that the surface of the dots has a non-metallic character, similar to that of the Si(111)-3 x 1-Ag surface. RAS also showed substantial differences between the structures, with a large infrared anisotropy for the metallic Ag islands consistent with anisotropic Drude-like intraband ...

2006-08-02

86

Metrological applications of X-ray waveguide thin film structures in X-ray reflectometry and diffraction  

International Nuclear Information System (INIS)

The effect of resonance, observed in X-ray waveguide layered structures in a characteristic way influences the scattering properties of the films. It is well known that the resonant region in the reflectivity shows a series of minima, usually very deep and extremely narrow. The positions and depths of the minima depend only on X-ray waveguide and quasi X-ray waveguide film structural properties, on the X-ray wavelength and on the incident beam divergence. In the present work we propose and discuss the application of the X-ray waveguide and quasi X-ray waveguide film structures as a tools to experimental evaluation of some quantities related to X-ray reflectometric and diffractometric measurements, like the beam divergence, wavelength, or angular distance. Examples of application of X-ray waveguide as an excellent tool for estimate the effective beam divergence are shown. Properties of the X-ray ...

2001-09-23

87

Fluctuation properties of strength function phenomena: A model study  

Energy Technology Data Exchange (ETDEWEB)

We study fluctuation properties of strength function phenomena by employing a quantum mechanical model where a single parent state couples with a large number of background states. The background system is devised in such a way that the classical dynamics of the system may show a regular, an irregular, or a chaotic character as a function of a single parameter. The coupling of the parent state to the background states produces a fragmentation of the parent state, giving rise to a strength function phenomenon. We study various measures of the strength function that characterize its bulk structure or fluctuation properties. They include energy moments, strength distribution, fractal dimensions of the strength function, and Fourier transform of the autocorrelation function. Some of these measures, such as strength distribution or Fourier transform of the autocorrelation function, reflect characteristic aspects of the dynamics ...

1997-07-01

88

Optical Properties and Wave Propagation in Semiconductor-Based Two-Dimensional Photonic Crystals  

Energy Technology Data Exchange (ETDEWEB)

This work is a theoretical investigation on the physical properties of semiconductor-based two-dimensional photonic crystals, in particular for what concerns systems embedded in planar dielectric waveguides (GaAs/AlGaAs, GaInAsP/InP heterostructures, and self-standing membranes) or based on macro-porous silicon. The photonic-band structure of photonic crystals and photonic-crystal slabs is numerically computed and the associated light-line problem is discussed, which points to the issue of intrinsic out-of-lane diffraction losses for the photonic bands lying above the light line. The photonic states are then classified by the group theory formalism: each mode is related to an irreducible representation of the corresponding small point group. The optical properties are investigated by means of the scattering matrix method, which numerically implements a variable-angle-reflectance experiment; comparison with experiments is ...

2002-12-31

89

Geochemical and petrographic properties of some Spitsbergen coals and dispersed organic matter  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the characteristics of selected parameters of organic matter of the Tertiary coal samples and organic matter of Carboniferous rock samples from the Spitsbergen. The coal samples were taken from Central Coal Basin (the Longyearbyen region) and from the Forlandsundet Basin (Oscar II Land, the Kaffioyra region). Samples of dispersed organic matter were collected from Suffolk Pynten and Sergeijevfjellet area in Sorkapp Land. The optical properties of coal samples are different from properties of dispersed organic matter. Macerals of vitrinite group dominate in all of the samples. The average content of vitrinite group macerals is much lower in dipersed organic matter samples than it is in coals. The average content of liptinite group macerals is a little lower, and inertinite group macerals is much higher. The average content of mineral matter is higher in organic matter samples than in coal samples. The average value of ...

2004-02-20

90

Interobserver agreement in ultrasonography of the finger and toe joints in rheumatoid arthritis.  

DEFF Research Database (Denmark)

OBJECTIVE: To evaluate the interobserver agreement of ultrasonographic assessment of finger and toe joints in patients with rheumatoid arthritis (RA) by 2 investigators with different medical backgrounds. METHODS: Ultrasonography and clinical examination were performed on 150 small joints of 30 patients with active RA. A General Electric LOGIQ 500 ultrasound unit with a 7-13-MHz linear array transducer was used. In each patient, 5 preselected small joints (second and third metacarpophalangeal, second proximal interphalangeal, first and second metatarsophalangeal) were examined independently on the same day by 2 ultrasound investigators (an experienced musculoskeletal radiologist and a rheumatologist with limited ultrasound training). Joint effusion, synovial thickening, bone erosions, and power Doppler signal were evaluated in accordance with an introduced 4-grade semiquantitative scoring system, on which the investigators ...

2003-01-01

91

Visible light photocatalytic activity and Photoelectrochemical property of Fe-doped TiO2 hollow spheres by sol?gel method  

British Library Electronic Table of Contents (United Kingdom)

Fe-doped TiO2 hollow spheres (Fe-THs) were synthesized by sol?gel process using carbon spheres as templates. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV?vis diffuse reflectance spectrum (DRS), N2 adsorption?desorption isotherms, Electron paramagnetic resonance (EPR) spectroscopy and Photoluminescence emission spectroscopy (PL). UV?vis spectra showed that Fe3+ doping could extend the absorption edge to the visible region. EPR spectra showed that Fe3+ was incorporated into the crystal lattice of TiO2, which could inhibit the recombination of photo-induced electron?hole pairs and improve the photocatalytic activity. The photocatalytic activities of the prepared samples were evaluated for the degradation of dye Reactive Brillia...

2011-01-01

92

Viscosity of the Earth's inner core: Constraints from nutation observations  

British Library Electronic Table of Contents (United Kingdom)

The gravitational torque applied on the Earth by the other celestial bodies generates periodic variations in the orientation of the Earth's rotation axis in space which are called nutations. Observations of Earth's nutations allow for insights into the physical properties of the inner core because of the presence of a normal mode, the Free Inner Core Nutation (FICN), which is characterized by a tilt of the inner core figure and rotation axes with respect to the mantle and outer core. The frequency of the FICN is controlled by the strength of the mechanical coupling acting at the inner core boundary (ICB) and by the ability of the inner core to deform under the action of centrifugal and gravitational forces. Attenuation of the FICN reflects energy dissipated by electromagnetic (EM) and visc...

2011-01-01

93

Study on fracture behaviour of Al?15%Mg2Si metal matrix composite with and without beryllium additions  

British Library Electronic Table of Contents (United Kingdom)

In this study, the influence of Beryllium (Be) content on the fracture behaviour of Al?15%Mg2Si composite was investigated. The results showed an increase in mechanical properties with increasing of Be content. The stress?strain curves of samples showed a same category of serrations reflecting non-uniform deformation. Scanning electron microscopy was employed to examine the crack nucleation and fracture model. The results indicate that Al?15%Mg2Si composite shows different behaviours of crack initiation and fracture for samples with and without Be. Differences observed in the fracture behaviour were attributed to microstructural changes as well as morphological aspects of primary Mg2Si particles.

2011-01-01

94

Spin polarisation and anomalous Hall effect in NiMnSb films  

International Nuclear Information System (INIS)

NiMnSb has attracted a great deal of interest as a spin injector/detector in spintronic devices because it has a Curie temperature of 728 K and is predicted to be half-metallic (100% spin polarized). NiMnSb has been reported to have greatly reduced surface polarization, and to lose its half metallicity above 80 K. Here we report the investigation of the surface polarisation and electronic structure of NiMnSb by measurement of the transport spin polarization using point contact Andreev reflection spectroscopy, and anomalous Hall effect in thin films on Si(0 0 1). A comparison to bulk properties is made.

2004-05-01

95

Optical characterization of In2S3 solar cell buffer layers grown by chemical bath and physical vapor deposition  

British Library Electronic Table of Contents (United Kingdom)

In this paper, we study the optical properties of indium sulfide thin films to establish the best conditions to obtain a good solar cell buffer layer. The In2S3 buffer layers have been prepared by chemical bath deposition (CBD) and thermal evaporation (PVD). Optical behavior differences have been found between CBD and PVD In2S3 thin films that have been explained as due to structural, morphological and compositional differences observed in the films prepared by both methods. The resultant refractive index difference has to be attributed to the lower density of the CBD films, which can be related to the presence of oxygen. Its higher refractive index makes PVD film better suited to reduce overall reflectance in a typical CIGS solar cell.

2008-01-01

96

Formation of Bimodal-Sized Structure and Its Tensile Properties in a Warm-Rolled and Annealed Ultrafine-Grained Ferrite/Cementite Steel  

British Library Electronic Table of Contents (United Kingdom)

An ultrafine-grained ferrite/cementite (UGF/C) steel with a local high density of cementite particles was fabricated through caliber-warm-rolling followed by annealing and resulted in a bimodal-sized microstructure. The characteristic bimodal-sized microstructure was attributed to the original ferrite-pearlite structure and cementite spacing, and reflected the original ferrite-pearlite structure. The smaller-sized clusters corresponded to the former pearlite regions and the larger-sized clusters to the proeutectoid ferrite regions. The cementite particles naturally localized within the former pearlite region. Most of the ferrite coarsening did not occur until the cementite particle spacing reached a critical value. The UGF/C microstructure with a bimodal grain size showed a yield strength ...

2008-01-01

97

Effective medium theory of the one-dimensional resonance phononic crystal  

International Nuclear Information System (INIS)

A general theoretical scheme to describe the effective modulus and mass density for acoustic metamaterials is presented. For such a purpose, an effective medium theory of a one-dimensional acoustic waveguide containing subwavelength-sized Helmholtz resonators is formulated. It is shown that, when the wavelength is much larger than the periodic length and the size of the resonators, the whole composite structure can be treated as an effective homogeneous medium in accounting for its acoustic properties. It is also shown that the acoustic characteristics, such as the effective modulus and the effective mass density, can be determined precisely from the transmission and the reflection data. The calculated effective modulus and effective mass density confirm that this structure behaves as a homogeneous metamaterial with a negative effective modulus in a frequency range just above the resonant frequency.

2008-02-06

98

Dielectric properties of sols of silver nanoparticles capped by alkyl carboxylate ligands  

British Library Electronic Table of Contents (United Kingdom)

Sols of silver nanoparticles in toluene were studied by broadband dielectric spectroscopy (10?3?105 Hz). The frequency dependences of the specific alternating current (ac) conductivity and the complex electric modulus were used to estimate the temperature/frequency intervals of long- and short-range charge transfer occurs, respectively. A considerable increase (by more than 30 ?C) in the Vogel temperature T 0 and the glass transition temperature T g in sols compared with the pure solvent was found. It can be hypothesized that these cooperative effects reflect the initial stage of the superlattice formation. Although the dielectric characteristics of sols are generally controlled by the conductivity relaxation, the dielectric response was observed in the high-frequency range (1?103 Hz) at l...

2011-01-01

99

Deterministic Factors of Stock Networks based on Cross-correlation in Financial Market  

CERN Document Server

The stock market has been known to form homogeneous stock groups with a higher correlation among different stocks according to common economic factors that influence individual stocks. We investigate the role of common economic factors in the market in the formation of stock networks, using the arbitrage pricing model reflecting essential properties of common economic factors. We find that the degree of consistency between real and model stock networks increases as additional common economic factors are incorporated into our model. Furthermore, we find that individual stocks with a large number of links to other stocks in a network are more highly correlated with common economic factors than those with a small number of links. This suggests that common economic factors in the stock market can be understood in terms of deterministic factors.

2007-01-01

100

Characterization of physically vapor deposited AF2400 thin films  

Energy Technology Data Exchange (ETDEWEB)

Anti-reflective coatings made with Teflon AF2400 had the highest damage thresholds recorded for physical vapor deposited coatings at the Lawrence Livermore National Laboratory damage facility. Physical vapor deposited layers of Teflon AF2400, a perfluorinated amorphous polymer, maintained the bulk optical properties of a high transmittance from 200 nm to 1600 nm, and a low refractive index. In addition, the refractive index can be intentionally reduced by control of two common deposition parameters, deposition rate and substrate temperature. Scanning electron microscopy and nuclear magnetic resonance observations indicated that morphological changes caused the variations in the refractive index rather than compositional changes. The coatings adhered to fused silica and silicon wafers under normal laboratory handling conditions.

1993-11-01

101

Antireflection coatings with FeSi2 layer: Application to spectrally selective infrared emitter  

British Library Electronic Table of Contents (United Kingdom)

We have developed efficient spectrally selective infrared (IR) emitters that can be utilized for thermophotovoltaic (TPV) power generation by using stainless steel (SUS304) substrates coated with b- FeSi2 thin films. To develop spectrally selective emitters, we theoretically propose antireflection (AR) coatings consisting of a single layer of a dielectric material having a high refractive index (~5) and are appropriate for use with metals such as stainless steels in the IR region. This type of AR coating is fabricated by sputtering a b- FeSi2 thin film on a polished SUS304 substrate. The reflectance in the IR region is successfully reduced to less than 10%. In addition, the AR properties are stable even at 700 K in air. Therefore, metals with AR coatings of b- FeSi2 can be applied to IR em...

2011-01-01

102

[Retrieval of spectral characteristics of hyperspectral sensor and retrieval of reflectance spectra].  

Science.gov (United States)

On-orbit spectral calibration of hyperspectral imaging data is a key step for quantitatively analyzing them. Like the atmospheric correction, accurate spectral calibration is very necessary for improved studies of land or ocean surface properties. Based on the previous literatures, a new method which coupled an optimization algorithm was developed to simultaneously retrieve the central wavelength and the full width at half maximum (FWHM) of the hyperspectral sensor without needing the in situ reflectance spectra. Firstly, the Hyperion data set simulated using MODTRAN4 with the Hyperion spectral specification was used to test the new method, and the results indicated that the maximum error was less than 0.1 and 0.7 nm for central wavelength and FWHM respectively when the spectral shift is 5 nm. Then the algorithm was applied to the Hyperion data acquired on May 20, 2008 over Heihe River Basin and it was iteratively performed for each detector of ...

2010-10-01

103

Andreev reflection and order parameter symmetry in heavy-fermion superconductors: the case of CeCoIn5  

International Nuclear Information System (INIS)

We review the current status of Andreev reflection spectroscopy on the heavy fermions, mostly focusing on the case of CeCoIn5, a heavy-fermion superconductor with a critical temperature of 2.3 K. This is a well-established technique to investigate superconducting order parameters via measurements of the differential conductance from nanoscale metallic junctions. Andreev reflection is clearly observed in CeCoIn5 as in other heavy-fermion superconductors. Considering the large mismatch in Fermi velocities, this observation seemingly appears to disagree with the Blonder-Tinkham-Klapwijk (BTK) theory. The measured Andreev signal is highly reduced to the order of maximum ?13% compared to the theoretically predicted value (100%). The background conductance exhibits a systematic evolution in its asymmetry over a wide temperature range from above the heavy-fermion coherence temperature down to well below the superconducting transition temperature. ...

2009-03-11

104

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 resolution, soft tissue ...

2007-03-01

105

Experimental research of stability of thin films on the basis of depleted uranium as reflecting coating for wavelength of 4.5 nm  

International Nuclear Information System (INIS)

In this paper, we present experimentally determined reflection factors of mirrors based on the depleted uranium and dependence of reflection factor on time of presence of samples on air.

2007-05-21

106

The influence of ultrasound on the fluoroquinolones antibacterial activity  

British Library Electronic Table of Contents (United Kingdom)

In this work, the antibacterial effect of fluoroquinolones (FQs) upon Escherichia coli (E.coli) was measured with and without application of 40kHz ultrasound (US) stimulation. The research results demonstrated that simultaneous application of 40kHz US apparently enhanced the antibacterial effectiveness of FQs. That is, the synergistic effect was observed and the bacterial viability was reduced when FQs and US were combined. In addition, various influencing factors, such as FQs drug concentration, US irradiation time and solution temperature, on the inhibition of E.coli were also investigated. The antibacterial activity was enhanced apparently with increasing of FQs drug concentration, US irradiation time and solution temperature. Furthermore, we discussed preliminarily the mechanism of US ...

2011-01-01

107

Serial Intravascular Ultrasound Analysis of the Impact of Myocardial Bridge on Neointimal Proliferation After Coronary Stenting in Patients with Acute Myocardial Infarction  

British Library Electronic Table of Contents (United Kingdom)

Background: Mechanisms underlying the association between myocardial bridge (MB)-stenting and in-stent restenosis (ISR) are still unclear. Objective: To assess the impact of MB on ISR using intravascular ultrasound (IVUS). Methods: In the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, 100 left anterior descending artery (LAD) culprit lesions (79 treated with paclitaxel-eluting stents [PES] and 21 treated with bare metal stents) were imaged with serial IVUS immediately postprocedure and at 13 months. Results: At baseline the LAD stent extended into the MB segment beyond the culprit lesion in seven patients (MB-stent group). In the remaining 93 patients the LAD stent was implanted only in the culprit lesion without extending into t...

2010-01-01

108

Magnetic resonance imaging of chronic aortic dissection  

International Nuclear Information System (INIS)

17 patients with chronic aortic dissection were examined by MRI. In 12 patients, comparison between gradient echo sequences and SE sequences was possible. Gradient echo sequences, unlike SE sequences, permitted evaluation of flow in the true and false lumen, reliable differentiation between thrombus and flowing blood and clear delination of the intimal flap. An additional comparison between transoesophageal ultrasound and MRT in 15 patients showed significant advantages in favour of MRI. In three patients MRI was able to detect more proximal origins of the dissection. Moreover, MRI allowed evaluation of the major aortic branches and their relation to the dissection; this was not possible with ultrasound. MRI plays an important role in the follow-up of chronic aortic dissections. (orig.).

109

Endoscopic snare papillectomy with biliary and pancreatic stent placement for tumors of the major duodenal papilla  

British Library Electronic Table of Contents (United Kingdom)

Background This study aimed to evaluate the feasibility, safety, and follow-up results of endoscopic papilletomy (ESP) with pancreatic and biliary duct stent placement for ampullary tumors. The therapeutic approach to benign ampullary tumors remains unsettled. The ESP procedure is a curative treatment option for benign papillary tumors, but ESP raises concerns about a relatively high risk for procedure-related complications such as pancreatitis. A pancreatic stent may protect against complications. Methods Between September 2000 and June 2008, 36 patients with ampullary tumors confined to the mucosa and no intraductal tumor growth underwent ESP. The preprocedural diagnostic tools included endoscopic ultrasound, transpapillary intraductal ultrasound, and endoscopic retrograde cholangiopancr...

2010-01-01

110

Assessment of Low Quantitative Ultrasound Values of Calcaneus in Chinese Mainland Women  

British Library Electronic Table of Contents (United Kingdom)

Calcaneus quantitative ultrasound (QUS) assessment is a safe and reliable method for evaluating skeletal status. Until now, considerable data have been accumulated on the distribution of QUS in Caucasian populations, whereas such data are still insufficient in Asian populations, especially in Chinese mainland. The present study aimed to obtain the distribution characteristic of calcaneus QUS in healthy Chinese women, and to further investigate the distribution of low bone mass by QUS stiffness index (SI). This study included 2,498 healthy Chinese females aged 10-87 yr. The QUS exhibited a characteristic mild rise and then fall pattern with increasing age. Age, body height, and weight were significant influencing factors on SI, especially age and weight. The prevalence of osteoporosis detec...

2006-01-01

111

Use of genetic parameters in coal classification  

Science.gov (United States)

The extensive reserves of mined coal types, their great variety and the complexity of the composition and properties, as well as their important role as an energy fuel and industrial feedstock, cause one to give special attention to their classification. Of course, one of the principal fields of technological processing of coal is coking. In addition to the production of blast furnace coke, in the future specialized plants will be developed for production of coke and other carbonized materials for non-blast-furnace processes (electrothermal processes, production of calcium carbide, ferroalloys, zinc, yellow phosphorus, copper, etc.). One important area is new nonfuel uses, including a number of processes for processing of coal feedstocks to obtain a wide range of carbonaceous materials (coal-graphite products, carbon black, adsorbents, etc.), liquid fuels, and chemical products. In choosing a given area of coal utilization a determining factor is the ...

1984-01-01

112

Structure and surface and catalytic properties of Mg-Al basic oxides  

Science.gov (United States)

Mg-Al mixed oxides with Mg/Al molar ratios of 0.5--9.0 were obtained by thermal decomposition of precipitated hydrotalcite precursors. The effect of composition on structure and surface and catalytic properties was studied by combining several characterization methods with ethanol conversion reactions. The nature, density, and strength of surface basic sites depended on the Al content. The catalyst activity and selectivity of Mg-Al mixed oxides in ethanol conversion reactions depended on composition. The dehydrogenation of ethanol to acetaldehyde and the aldol condensation to n-butanol both involved the initial surface ethoxide formation on a Lewis acid-strong base pair. The dehydration of ethanol to ethylene, and the coupling and dehydration to diethyl ether increased with Al content, probably reflecting the density increase of both Al{sup 3+}-O{sup 2{minus}} pairs and low- and medium-strength basic sites. Pure Al{sub 2}O{sub 3} displayed the ...

1998-09-10

113

Spectral dependence of ultrasonic attenuation for hydrided Zr-2.5%Nb Alloy  

International Nuclear Information System (INIS)

The cold-worked Zr-2.5%Nb alloy is used as material for the pressure tubes in CANDU nuclear reactors. During the service life in reactor, diffusion of hydrogen and/or deuterium in the pressure tubes wall occur. Below a certain temperature, a stable hydride of zirconium is formed, as a brittle phase which can lead to catastrophic failures. For this reason, it is very important to be able to investigate the hydrogen effect on the micro structural properties of zirconium alloys. In the present paper a non-destructive testing technique is used, known as ultrasonic spectral analysis. When an ultrasonic signal traverses a medium, the frequency components associated with the input signal are altered. By frequency analysing the reflected signals, it is possible to study and compare the material properties. The two major parameters measured in ultrasonic spectroscopy are the attenuation and the velocity of the waves. Attenuation is ...

2009-10-12

114

SnO{sub 2} thin films morphological and optical properties in terms of the Boubaker Polynomials Expansion Scheme BPES-related Opto-Thermal Expansivity {psi}{sub AB}  

Energy Technology Data Exchange (ETDEWEB)

In this study, SnO{sub 2} thin films have been grown using spray pyrolysis technique on glass substrates under a substrate temperature (T{sub s} = 440 {sup o}C). The precursors were methanol CH{sub 4}O and anhydrous tin tetrachloride. XRD analyses yielded strong (1 1 0)-(1 0 1)-(2 0 0) X-ray diffraction peaks which are characteristics to tetragonal crystals. Atomic Force Microscopy (AFM) analyses showed the existence of clusters with particular pyramidal shapes. The main part of this study concerns the optical measurements of transmittance T({lambda}) and reflectance R({lambda}) spectra inside 250-1800 nm domain. Conjoint optical and thermal properties were deduced using the Amlouk-Boubaker Opto-Thermal Expansivity {psi}{sub AB}. The obtained value: {psi}{sub AB} {approx} 23.4 m{sup 3} s{sup -1} helped situating the performance of the as-grown SnO{sub 2} compound among most known PV-T oxides like ZnO and TiO{sub 2}.

2010-02-04

115

SnO2 thin films morphological and optical properties in terms of the Boubaker Polynomials Expansion Scheme BPES-related Opto-Thermal Expansivity ?AB  

International Nuclear Information System (INIS)

In this study, SnO2 thin films have been grown using spray pyrolysis technique on glass substrates under a substrate temperature (Ts = 440 oC). The precursors were methanol CH4O and anhydrous tin tetrachloride. XRD analyses yielded strong (1 1 0)-(1 0 1)-(2 0 0) X-ray diffraction peaks which are characteristics to tetragonal crystals. Atomic Force Microscopy (AFM) analyses showed the existence of clusters with particular pyramidal shapes. The main part of this study concerns the optical measurements of transmittance T(?) and reflectance R(?) spectra inside 250-1800 nm domain. Conjoint optical and thermal properties were deduced using the Amlouk-Boubaker Opto-Thermal Expansivity ?AB. The obtained value: ?AB ? 23.4 m3 s-1 helped situating the performance of the as-grown SnO2 compound among most known PV-T oxides like ZnO and TiO2.

2010-02-04

116

Effect of dysprosium doping on the optical properties of SrS:Dy,Cl phosphor  

International Nuclear Information System (INIS)

The fundamental optical properties of dysprosium (Dy) doped strontium sulfide bulk samples for various dopant concentrations from 0.1 to 1.0 at.% were investigated by X-ray diffraction (XRD), electron paramagnetic resonance spectroscopy (EPR), room temperature photoluminescence (PL), photoluminescence excitation (PLE) and diffuse reflectance spectroscopy (DRS). Investigations by electron paramagnetic resonance yielded the state of Dy in the sample as Dy3+. An additional ESR line due to F+ center was observed. The PL emission spectrum consisted of several intense lines and a number of weaker ones which were identified as transitions between energy levels of Dy3+. The optimum doping concentration for maximum intensity was found to be 0.25 at.%. Blue shift of the absorption edge energy and red shift of the PLE spectrum were observed with increasing doping concentration. The former is due to Burstein-Moss (BM) effect and the latter is attributed ...

2010-08-13

117

Deposition of Cu film on SiO_2 using a partially ionized beam  

International Nuclear Information System (INIS)

Ion bombardment during deposition can significantly modify the film properties. In the partially ionized beam deposition, ions derived from the depositing material, i.e., the self-ions, are used during deposition. Cu films were deposited on SiO_2 substrates at room temperature using 1% Cu self-ions with an energy ranging between 0--4 keV. We studied the microstructures of the Cu films using x-ray diffraction and transmission electron microscopy, measured the impurity level inside the films using secondary ion mass spectrometry, and performed the resistivity measurements using a four point probe. The results indicate that there is an optimum ion energy around 2 keV at which, the integrated x-ray intensity ratio I(111)/I(200) reaches its maximum value indicating a strong left-angle 111 right-angle texture, while the impurity concentration and resisitivity are minimum. The correlation between the structural, compositional and electrical properties ...

1990-01-01

118

Deposition of Cu film on SiO sub 2 using a partially ionized beam  

Energy Technology Data Exchange (ETDEWEB)

Ion bombardment during deposition can significantly modify the film properties. In the partially ionized beam deposition, ions derived from the depositing material, i.e., the self-ions, are used during deposition. Cu films were deposited on SiO{sub 2} substrates at room temperature using 1% Cu self-ions with an energy ranging between 0--4 keV. We studied the microstructures of the Cu films using x-ray diffraction and transmission electron microscopy, measured the impurity level inside the films using secondary ion mass spectrometry, and performed the resistivity measurements using a four point probe. The results indicate that there is an optimum ion energy around 2 keV at which, the integrated x-ray intensity ratio {ital I}(111)/{ital I}(200) reaches its maximum value indicating a strong {l angle}111{r angle} texture, while the impurity concentration and resisitivity are minimum. The correlation between the structural, compositional and electrical ...

1990-05-01

119

Deposition of Cu film on SiO sub 2 using a partially ionized beam  

Science.gov (United States)

Ion bombardment during deposition can significantly modify the film properties. In the partially ionized beam deposition, ions derived from the depositing material, i.e., the self-ions, are used during deposition. Cu films were deposited on SiO{sub 2} substrates at room temperature using 1% Cu self-ions with an energy ranging between 0--4 keV. We studied the microstructures of the Cu films using x-ray diffraction and transmission electron microscopy, measured the impurity level inside the films using secondary ion mass spectrometry, and performed the resistivity measurements using a four point probe. The results indicate that there is an optimum ion energy around 2 keV at which, the integrated x-ray intensity ratio {ital I}(111)/{ital I}(200) reaches its maximum value indicating a strong {l angle}111{r angle} texture, while the impurity concentration and resisitivity are minimum. The correlation between the structural, compositional and electrical ...

1990-05-01

120

Analysis of the relationship between the coal properties and their liquefaction characteristics by using the coal data base; Tanshu data base ni yoru tanshitsu to ekika tokusei no kaiseki  

Energy Technology Data Exchange (ETDEWEB)

The relationship between coal properties and liquefaction or gasification characteristics was analyzed by using the analysis and test results and liquefaction characteristics in the coal data base. On liquefaction reaction, the close relation between an oil yield and coal constituent composition or a coal rank is well-known. Various multivariable regression analyses were conducted by using 6 factors as variables such as calorific value, volatile component, O/C and H/C atomic ratios, exinite+vitrinite content and vitrinite reflectance, and liquefaction characteristics as variate. On liquefaction characteristics, the oil yield of dehydrated and deashed coals, asphaltene yield, hydrogen consumption, produced water and gas quantities, and oil+asphaltene yield were predicted. The theoretical gasification efficiency of each specimen was calculated to evaluate the liquefaction reaction obtained. As a result, the oil yield increased with H/C atomic ...

1996-10-28

121

Perspectives in radiation and health: reflections on the International Conference in Beer Sheva.  

UK PubMed Central (United Kingdom)

Insofar as international conferences reflect the state of development of the subject under discussion, they provide an opportunity to question, at a rather fundamental level, the direction of and progress...Full Text Available

1997-12-01

122

ERG Expression Levels in Prostate Tumors Reflect Functional ...  

Science.gov (United States)

... Title : ERG Expression Levels in Prostate Tumors Reflect Functional Status of the Androgen Receptor (AR) as a Consequence of Fusion of ERG ...

123

Fault analysis in the very shallow seismic reflection method. 2; Gokusenso hanshaho ni okeru danso kaiseki. 2  

Energy Technology Data Exchange (ETDEWEB)

Fault analysis is required in addition to the ordinary process of structural analysis (CDP stacking) for the examination of discontinuity in the reflection horizon in question. The fault shape restoration principle is that the reflection point of a reflection wave observed at a certain receiving point is on an ellipse with the shock point and receiving point at its focal points and that the sum of the distances between the reflection point and the focal points is equal to the reflection wave propagation time. The DMO velocity is worked out by calculation using the positive travel time and inverse travel time from the common reflection surface. When the reflection surface is inclined by {theta}, the average interval velocity/cos{theta} is called the DMO velocity. When the reflection surface inclination and the average ...

1997-05-27

125

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 mm3, 2.2 s/image, 0.3 ...

2008-11-21

126

Early prenatal diagnosis of conjoined twins at 7 weeks and 6 days' gestation with two-dimensional Doppler ultrasound: a case report  

UK PubMed Central (United Kingdom)

This case report presents the prenatal diagnosis of conjoined twins at 7 weeks and 6 days’ gestation according to the last menstrual period and 6 weeks and 4 days’ gestation according...Full Text Available

128

Reflective diffraction grating  

Energy Technology Data Exchange (ETDEWEB)

Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

2003-06-24

130

Hyaluronan-lecithin foils and their properties  

Energy Technology Data Exchange (ETDEWEB)

Thin, elastic foils of good resistance to the air exposure, patented as wound healing aids, were prepared by evaporation of a blend of lecithin (L) and sodium hyaluronan (H) taken under varying proportions. The contact angle for water, glycerol, formamide, ethylene glycol and diiodomethane, was determined for these foils. The contact angle was correlated against the H:L foil composition. For all liquids but formamide the highest contact angle was noted for the H:L = 2:1 (g g{sup -1}) ratio. The contact angles provided estimation of the work of adhesion. At the same L:H ratio the work of adhesion was the lowest. It was suggested that lecithin cross-linked hyaluronan. Since the work of adhesion of the studied liquids was similar to that of diiodomethane, it could be concluded that almost all functional groups on the foil surface were completely blocked. Perhaps, at H:L = 2:1 (g g{sup -1}) a stoichiometric complex of hyaluronic acid with lecithin was formed, and polar functional groups ...

2006-01-10

131

Grazing incidence X-ray diffraction and neutron reflection studies of semi-crystalline polymer surfaces and interfaces[Polymers; Crystallisation behaviour  

Energy Technology Data Exchange (ETDEWEB)

This thesis is concerned with the crystallisation behaviour of polymers near to a free surface or a buried interface. The properties of polymers are expected to differ significantly near to an interface (either with air or another polymer), due to the contributions of (a) chain configurations induced at the interface, and (b) different mobilities between interfacial regions and the bulk of the sample. For a semi-crystalline polymer, properties such as the degree of crystallinity and the crystallisation kinetics may be enhanced near to a free surface. Grazing incidence x--ray diffraction (GIXD) is used to investigate such effects in poly(ethylene terphthalate) (PET), showing that a lower crystallisation temperature is obtained at the surface, and the crystallisation kinetics are faster at the surface for all temperatures. It is proposed that in thin films of PET, this surface-induced ordering provides nucleation sites for crystallisation in the ...

2002-07-01

132

Ellipsometric and spectral measurements in the study of chemically coloured 304 stainless steel selective surfaces  

Energy Technology Data Exchange (ETDEWEB)

Ellipsometric studies and reflectance measurements on five anodized coloured 304 stainless steel samples (Brown, Violet, Blue, Light Grey and Dark Grey) are reported. The optical properties, solar absorptance and thermal emittance of samples have been obtained. Measured values of absorptance lay between 0.75-0.87 together with a near normal emittance value approx. =0.10 at 100/sup 0/C. The total hemispherical emittance has been measured at 100 and 200/sup 0/C for the sample having the best selective surface. This study shows that the blue coloured surface has the most favourable combination of radiation properties. The surface deteriorates at temperatures above 210/sup 0/C. Oxidation is assumed to be the deterioration mechanism. The different samples exhibited difference in the /PSI/ and ..delta.. parameters as determined by ellipsometry both before and after heat treatments. When brown and violet samples were coated with a ...

1982-09-01

133

Reflected-shock initiation of explosives  

Energy Technology Data Exchange (ETDEWEB)

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

1993-08-01

134

Turning the Moon into a Solar Photovoltaic Paradise  

Science.gov (United States)

Lunar resource utilization has focused principally on the extraction of oxygen from the lunar regolith. A number of schemes have been proposed for oxygen extraction from Ilmenite and Anorthite. Serendipitously, these schemes have as their by-products (or more directly as their "waste products"), materials needed for the fabrication of thin film silicon solar cells. Thus lunar surface possesses both the elemental components needed for the fabrication of silicon solar cells and a vacuum environment that allows for vacuum deposition of thin film solar cells directly on the surface of the Moon without the need for vacuum chambers. In support of the US space exploration initiative a new architecture for the production of thin film solar cells on directly on the lunar surface is proposed. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar regolith thin films (anti-reflect coatings and ...

2006-01-01

135

The 10 basic requirements for a scientific paper reporting antioxidant, antimutagenic or anticarcinogenic potential of test substances in in vitro experiments and animal studies in vivo  

DEFF Research Database (Denmark)

There is increasing evidence that chemicals/test substances cannot only have adverse effects, but that there are many substances that can (also) have a beneficial effect on health. As this journal regularly publishes papers in this area and has every intention in continuing to do so in the near future, it has become essential that studies reported in this journal reflect an adequate level of scientific scrutiny. Therefore a set of essential characteristics of studies has been defined. These basic requirements are default properties rather than non-negotiables: deviations are possible and useful, provided they can be justified on scientific grounds. The 10 basic requirements for a scientific paper reporting antioxidant, antimutagenic or anticarcinogenic potential of test substances in in vitro experiments and animal studies in vivo concern the following areas: (1) Hypothesis-driven study design; (2) The nature of the test substance; (3) Valid ...

2003-01-01

136

Synthesis and photoluminescence properties of Sm3+-doped LaMgB5O10 and GdMgB5O10  

International Nuclear Information System (INIS)

Luminescence and reflection spectra as well as luminescence kinetics of the 1 mol% Sm3+-doped crystalline lanthanum magnesium meta borate (LaMgB5O10) and gadolinium magnesium meta borate (GdMgB5O10) were analyzed. Materials were synthesized by conventional solid state route and showed bright orange-red emission under UV excitation. Emission spectra contain sharp and well resolved Sm3+4G5/2#->#6HJ transitions indicating a strong crystal-field effect. In case of gadolinium compound energy transfer between Gd3+ and Sm3+ was detected. The luminescent kinetics of the Sm3+ in analyzed powders is characterized by single exponential decay and experimental values vary in the range 2.2-2.4 ms. - Research highlights: ? Phosphorescence of samarium-doped lanthanide magnesium meta borates. ? Bright and well resolved orange-red emission of Sm3+ under UV excitation. ? Energy transfer from Gd3+ to Sm3+ in gadolinium magnesium meta borate is observed. ? The decay lifetimes is ...

2011-07-01

137

Structure and Function Evolution of Thiolate Monolayers on Gold  

Energy Technology Data Exchange (ETDEWEB)

The use of n-alkanethiolate self-assembled monolayers on gold has blossomed in the past few years. These systems have functioned as models for common interfaces. Thiolate monolayers are ideal because they are easily modified before or after deposition. The works contained within this dissertation include interfacial characterization (inbred reflection absorption spectroscopy, ellipsometry, contact angle, scanning probe microscopy, and heterogeneous electron-transfer kinetics) and various modeling scenarios. The results of these characterizations present ground-breaking insights into the structure, function, and reproducible preparation of these monolayers. Surprisingly, three interfacial properties (electron-transfer, contact angle, and ellipsometry) were discovered to depend directly on the odd-even character of the monolayer components. Molecular modeling was utilized to investigate adlayer orientation, and suggests that these effects are ...

2006-05-01

138

Second-law efficiency of solar-thermal cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

Properly quantified performance of a solar-thermal cavity receiver must not only account for the energy gains and losses as dictated by the First Law of thermodynamics, but it must also account for the quality of that energy. However, energy quality can only be determined from the Second Law. In this paper an equation for the Second-Law efficiency of a cavity receiver is derived from the definition of available energy or availability (occassionally called exergy), which is a thermodynamic property that measures the maximum amount of work obtainable when a system is allowed to come into unrestrained equilibrium with the surrounding environment. The fundamental concepts of the entropy and availability of radiation are explored from which a convenient relationship among the reflected cone half angle, the insolation, and the concentrator geometric characteristics is developed as part of the derivation of the Second-Law efficiency. A comparison is ...

1983-10-01

139

Morphology of wood species affecting wood-thermoplastic interaction: microstructure and mechanical adhesion  

Scientific Electronic Library Online (English)

Abstract in english The main objective of the research presented here is to relate anatomical features of wood species that affect the interactions between polymeric phases and performance of wood plastic composites (WPC). These interactions are related to the probable interlocking volume and surface area for stress transfer in a WPC. Composites were produced from different wood species and analyzed using SEM (scanning electron microscopy). Results showed that wood species with high interfac (more) ial areas may increase mechanical interlocking, reflected in the viscous constant of the Maxwell model. A complicating factor is that the relation of cell wall thickness-lumen diameter and the interconnectivity between wood cells in a wood, affect the potential for cell collapse. When wood cells collapse, the penetration of the thermoplastic into the wood structure is almost always ceased. The collapse of wood cells during extrusion-injection molding processes reduced ...

2009-01-01

140

Microstructure and magnetic properties of nanocrystalline Fe75Si20M5 (M = Al, B, Cr) powders  

International Nuclear Information System (INIS)

Nanocrystalline Fe75Si20M5 (M = Al, B and Cr) powders were synthesized by mechanical alloying in a planetary ball mill from high purity elemental powders. Evolution of non-equilibrium solid solutions of ?-Fe[Si,(Al, B, Cr)] with a nanocrystalline structure was accompanied by the introduction of a large number of dislocation defects in the course of the milling process. Fe sites get substituted by Si and M (M = Al, B, Cr) atoms during the milling process. The structural change and the resulting disorder are reflected in the changes in the lattice parameter and average magnetic moment of the powders milled for various time periods. The effective magnetic anisotropy increases linearly with the milling time. An increase in coercivity with increasing milling time was observed which could be attributed to the introduction of dislocations and the reduction in the powder particle size during milling. The presence of dislocations and grain boundaries increases the ...

2008-08-21

141

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

142

Low-temperature properties of ternary magnetic rare-earth transition-metal germanides with the Sc sub 5 Co sub 4 Ge sub 10 -type structure  

Energy Technology Data Exchange (ETDEWEB)

DC resistivity, dc magnetization, and specific heat of eight Sc{sub 5}Co{sub 4}Ge{sub 10}-type crystal-structure compounds R{sub 5}T{sub 4}Ge{sub 10} for R = Dy, Ho, Er, Tm, and T = Rh and Ir are presented. The resistivity, single-crystal magnetization, and specific-heat results show that in all those compounds, the magnetic moments order antiferromagnetically in the c direction at low temperature. However, in the Er and Tm compounds, the magnetizations along x-y hard directions do not show any anomalies above 2.0 K. This suggests that the ordered Er and Tm ions, which have positive quadrupole coefficients, interact with a crystal field that has an electronic potential valley along the c axis. The fitting of the hard axis magnetizations to Curie-Weiss law suggests that the resulting antiferromagnetic-like {theta} reflects the strength of the crystal-field torque on the magnetic moments rather than the strength of antiferromagnetic exchange.

1988-01-01

143

Low temperature properties of ternary magnetic rare earth transition metal germanides with the Sc/sub 5/Co/sub 4/Ge/sub 10/-type structure  

Energy Technology Data Exchange (ETDEWEB)

DC resistivity, dc magnetization, and specific heat of eight Sc/sub 5/Co/sub 4/Ge/sub 10/-type crystal structure compounds R/sub 5/T/sub 4/Ge/sub 10/ for R = Dy, Ho, Er, Tm, and T = Rh and Ir are presented. The resistivity, single crystal magnetization, and specific heat results show that in all those compounds, the magnetic moments order antiferromagnetically in the c direction at low temperature. However, in the Er and Tm compounds, the magnetizations along x-y hard directions do not show any anomalies above 2.0 K. This suggests that the ordered Er and Tm ions, which have positive quadrupole coefficients ..cap alpha../sub j/, interact with a crystal field that has an electronic potential valley along the c axis. The fitting of the hard axis magnetizations to Curie-Weiss law suggests that the resulting antiferromagnetic-like theta reflects the strength of the crystal field torque on the magnetic moments rather than the strength of antiferromagnetic exchange. 123 ...

1988-07-01

144

Investigating the complex X-ray spectrum of a broad-line 2MASS red quasar: XMM-Newton observation of FTM 0830+3759  

CERN Document Server

We report results from a 50 ks XMM-Newton observation of the dust-reddened broad-line quasar FTM 0830+3759 (z=0.413) selected from the FIRST/2MASS Red Quasar survey. For this AGN, a very short 9 ks Chandra exposure had suggested a feature-rich X-ray spectrum and HST images revealed a very disturbed host galaxy morphology. Contrary to classical, optically-selected quasars, the X-ray properties of red (i.e. with J-Ks> 1.7 and R-Ks> 4) broad line quasars are still quite unexplored, although there is a growing consensus that, due to moderate obscuration, these objects can offer a unique view of spectral components typically swamped by the AGN light in normal, blue quasars. The XMM-Newton observation discussed here has definitely confirmed the complexity of the X-ray spectrum revealing the presence of a cold (or mildly-ionized) absorber with Nh ~10^{22} cm^-2 along the line of sight to the nucleus and a Compton reflection component accompanied ...

2010-01-01

145

Intra-day and regime-switching dynamics in electricity price formation  

Energy Technology Data Exchange (ETDEWEB)

This paper analyses the complex, non-linear effects of spot price drivers in wholesale electricity markets: their intra-day dynamics and transient irregularities. The context is the UK market, after the reforms introduced in March 2001, analysed with an original set of price drivers reflecting economic, technical, strategic, risk, behavioural and market design effects. Models are estimated separately as daily time-series of the 48 half-hourly trading periods. All coefficients exhibit substantial intra-day variation, relating to the heterogeneity of operating plants and market design aspects. This reveals a market responding to economic fundamentals and plant operating properties, with learning and emergent financial characteristics, as well as some strategic manipulation of capacity, most effectively exercised by the more flexible plants. Using regime-switching parameters, the effects of capacity margin and inter-day capacity adjustment are ...

2008-07-15

146

Interfaces in aquatic ecosystems: Implications for transport and impact of anthropogenic compounds  

Energy Technology Data Exchange (ETDEWEB)

Mechanisms that govern transport, accumulation and toxicity of persistent pollutants at interfaces in aquatic ecosystems were the foci of this thesis. Specific attention was paid to humic substances, their occurrence, composition, and role in exchange processes across interfaces. It was concluded that: The composition of humic substances in aquatic surface microlayers is different from that of the subsurface water and terrestrial humic matter. Levels of dissolved organic carbon (DOC) in the aquatic surface microlayer reflect the DOC levels in the subsurface water. While the levels and enrichment of DOC in the microlayer generally show small variations, the levels and enrichment of particulate organic carbon (POC) vary to a great extent. Similarities exist between aquatic surface films, artificial semi-permeable and biological membranes regarding their structure and functioning. Acidification and liming of freshwater ecosystems affect DOC:POC ratio and humic ...

1996-11-01

147

Interaction of energetic beams with metals and semiconductors - a computational approach  

International Nuclear Information System (INIS)

In a vacuum insulator, the narrow electron beam emitted from the cathode impinges on the anode and raises its temperature and also may produce high thermal stress. This high thermal stress, in conjuction with the surface electrostatic pressure may rupture the surface and detach particles from it. In this thesis, the interaction of high energy electron and laser beams with metals and semiconductors is investigated. The differential equations governing the physical processes involved in the interaction are solved by the finite element method. Effects of beam penetration into the material, variable beam reflectance at the surface, finite beam size and dependence of material properties on temperature are accounted for. The two-phase moving boundary problem, also known as the Stefan problem, is solved by an enthalpy formulation of the heat equation. Material deformation by thermal stresses caused by high temperature gradients and electrostatic ...

1984-01-01

148

Improved eddy-current inspection for steam generator tubing  

Energy Technology Data Exchange (ETDEWEB)

Computer programs have been written to allow the analysis of different types of eddy-current probes and their performance under different steam generator test conditions. The probe types include the differential bobbin probe, the absolute bobbin probe, the pancake probe and the reflection probe. The generator test conditions include tube supports, copper deposits, magnetite deposits, denting, wastage, pitting, cracking and IGA. These studies are based mostly on computed values, with the limited number of test specimens available used to verify the computed results. The instrument readings were computed for a complete matrix of the different test conditions, and then the test conditions determined as a function of the readings by a least-squares technique. A comparison was made of the errors in fit and instrument drift for the different probe types. The computations of the change in instrument reading due to the defects have led to an inversion'' ...

1989-01-01

149

Evaluation of passive films by photo and impedance spectroscopy; Bunkoho oyobi inpidansu ho ni yoru himaku hyoka  

Energy Technology Data Exchange (ETDEWEB)

The passive films formed on iron metal, alloys or stainless steel are extremely thin oxides or hydroxides and possess the properties of high chemical stability in the environment. These films show characteristics interested both electrical as well as electrochemical point of view due to the thin thickness of the films. Auger Electron Spectroscopy, X-ray Photoelectron spectroscopy and so on which are the conventional electrochemical measurement methods or the surface analysis methods are used for the analysis and evaluation of these films, however, at present, the application of research technique focusing the superconductor characteristics of the films are tried. Although, the potential modulation reflection spectroscopy method has merits like possibility of in-situ measurement, high precision, possibility of stable analysis even for extremely thin film and so forth, it has also demerits like difficulty to response the potential modulation of ...

1995-09-20

150

Enhancement of corrosion protection efficiency of iron by poly(aniline-co-amino-naphthol-sulphonic acid) nanowires coating in highly acidic medium  

International Nuclear Information System (INIS)

Nanowires of copolymers film based on aniline and 1-amino-2-naphthol-4-sulphonic acid were electrochemically synthesized on the iron electrode by cyclic voltammetry using oxalic acid as a supporting electrolyte. Protective properties of copolymer film on the iron surface in 1.0 M HCl solution was investigated by chronoamperometry, potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results showed that the copolymer film showed the significant shifting in the corrosion potential and greater charge transfer resistance. Moreover, the copolymer showed the larger degree of surface coverage onto the iron surface, reflecting the higher protection for corrosion of the iron in acidic medium. In addition, the film constitutes a physical as well as a chemical barrier layer due to the presence of -OH and -NH groups in ANSA unit, which provides passivity protection in polymer coatings. The mechanism of corrosion ...

2010-11-30

151

Composition Dependence of the Photocatalytic Activities of BiOCl1-xBrx Solid Solutions under Visible Light  

British Library Electronic Table of Contents (United Kingdom)

Abstract We prepared BiOCl1-xBrx (x=0-1) solid solutions and characterized their structures, morphologies, and photocatalytic properties by X-ray diffraction, diffuse reflectance spectroscopy, scanning electron microscopy, Raman spectroscopy, photocurrent and photocatalytic activity measurements and also by density functional theory calculations for BiOCl, BiOBr, BiOCl0.5Br0.5. Under visible-light irradiation BiOCl1-xBrx exhibits a stronger photocatalytic activity than do BiOCl and BiOBr, with the activity reaching the maximum at x=0.5 and decreasing gradually as x is increased toward 1 or decreased toward 0. This trend is closely mimicked by the photogenerated current of BiOCl1-xBrx, indicating that the enhanced photocatalytic activity of BiOCl1-xBrx with respect to those of BiOCl and BiO...

2011-01-01

152

Characterization of proton exchange membrane materials for fuel cells by solid state nuclear magnetic resonance  

Energy Technology Data Exchange (ETDEWEB)

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-angle X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the normal hydration ...

2010-03-15

153

Augmentation of radiative heat transfer in an infinite cylindrical pipe enclosing a participating gas  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to identify the radiative heat transfer augmentation by a coaxial cylinder introduced in the infinite cylindrical pipe enclosing a participating gas. The gas is either a mixture of water vapor and carbon dioxide or gray. The gas is assumed to be homogeneous at a constant temperature, and has a refractive index of unity. All of the surfaces are opaque and gray, diffusely emitting and reflecting at a constant temperature. The effect of system diameter, diameter ratio, wall emittances, gas and surface temperatures, mixture component on heat transfer augmentation are studied by using the zone method with participating gas radiative properties evaluated from the weighted sum of gray gases model. From the radiative equilibrium condition, the installed wall temperature is formulated and calculated by the iteration method. If the medium is a gray gas, the augmentation observed are negligible. For the range of values studied ...

1992-10-01

154

Morphology-controlled synthesis and novel microwave electromagnetic properties of hollow urchin-like chain Fe-doped MnO2 under 10 T high magnetic field  

International Nuclear Information System (INIS)

Fe-doped MnO2 with a hollow sea urchin-like ball chain shape was first synthesized under a high magnetic field of 10 T. The formation mechanism was investigated and discussed in detail. The synthesized samples were characterized by XRD, SEM, TEM, EMPA, and vector network analysis. By doping MnO2 with Fe, the relative complex permittivity of MnO2 and its corresponding loss tangent clearly decreases, but its relative complex permeability and its corresponding loss tangent markedly increases. Moreover, the theoretically calculated values of reflection loss show that with increasing the Fe content, the as-prepared Fe-doped MnO2 exhibits good microwave absorption capability. -- Graphical Abstract: Fe-doped MnO2 with a hollow sea urchin-like ball chain shape was first synthesized in a high magnetic field of 10 T via a simple chemical process. Display Omitted Highlights: ? Fe-doped MnO2 with a hollow sea urchin-like ball chain shape was first synthesized. ? We ...

2011-05-01

155

Process of preparing metal parts to be heated by means of infrared radiance  

Energy Technology Data Exchange (ETDEWEB)

A method for preparing metal for heating by infrared radiance to enable uniform and consistent heating. The surface of one or more metal parts, such as aluminum or aluminum alloy parts, is treated to alter the surface finish to affect the reflectivity of the surface. The surface reflectivity is evaluated, such as by taking measurements at one or more points on the surface, to determine if a desired reflectivity has been achieved. The treating and measuring are performed until the measuring indicates that the desired reflectivity has been achieved. Once the treating has altered the surface finish to achieve the desired reflectivity, the metal part may then be exposed to infrared radiance to heat the metal part to a desired temperature, and that heating will be substantially consistent throughout by virtue of the desired reflectivity.

2009-06-09

156

Visualization of the salivary glands. CT and MRI  

International Nuclear Information System (INIS)

For the evaluation of diseases of salivary origin, ultrasound and/or sialography is recommended instead of MRI. In cases of salivary tumor, ultrasound may be helpful in delineating superficial tumors. For small tumors no further imaging is needed. When dealing with a large tumor or a tumor in the deep lobe of the parotid gland, MRI is the preferred imaging method. Not only does MRI provide a large variety of soft tissue signal differences, but also the multiplanar facilities are helpful in delineating the extent of the tumor, whether located in the submandibular, sublingual, or parotid gland. Skull base invasion is often well seen by MRI. Subtle changes may be missed and in those cases CT is recommended to exclude or prove destruction of the skull base. For the evaluation of patients presenting with a recurrent pleomorphic adenoma, MRI is recommended in all patients. MRI delineates the extent and number of recurrent tumors better than palpation ...

157

MR imaging of experimental intramuscular hemorrhage at 0. 02 T; Contrast enhancement with Gd-DOTA  

Energy Technology Data Exchange (ETDEWEB)

Intramuscular hermorrhage was induced by injecting autologous blood into the paraspinal muscle of 8 rabbits. In order to evaluate the time-dependent changes of hemorrhage observed on MRI, the animals were imaged at different stages of blood resolution at 0.02 tesla (T), and control examined with ultrasound using a 7.5 MHz linear transducer. Six inversion recovery sequences (TR=1 000 ms. TE=30 ms, and TI=18, 48, 148, 201, 302, and 398 ms) were used for the invivo calculation of T1 relaxation times. IR 1 000 (398)/30 imaging was performed before and after the Gd-DOTA administration. The hemorrhage was evident on MR images throughout the study, especially on the T2 weighted (SE 1 000/100) images. MRI showed the healing lesion longer than ultrasound. The T1 relaxation time increased during the time of resolution. Lesions on days 4 to 7 enhanced in intensity after the injection of Gd-DOTA. (orig.).

1990-09-01

158

Idiopathic renal hematuria in a military working dog.  

Science.gov (United States)

A 1.5-year-old male Belgian Malinosis Military Working Dog presented with a 1-month history of intermittent hematuria. Diagnostic ultrasound and contrast radiography demonstrated large blood clots in the urinary bladder and a filling defect in the right renal pelvis. At surgery, clotted blood was present in the right ureter and bladder. Following right nephrectomy, the dog returned to training. One month later, elevations in urea nitrogen and creatinine were noted. Hematuria recurred at 3 months and the dog was found dead in its kennel. Necropsy showed a blood-filled left renal pelvis and ureter. PMID:1454185

1992-10-01

159

Possibility of applying the method of multiple attenuated total internal reflection to investigate adsorption on coal  

Energy Technology Data Exchange (ETDEWEB)

The possibility of studying the adsorption of acetic acid vapour on coal by the method of multiple attenuated total internal reflection by two proposed procedures has been shown.

1981-01-01

160

Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography  

International Nuclear Information System (INIS)

Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ...

2010-08-01

161

Reflection of electromagnetic waves by a nonuniform plasma layer covering a metal surface  

International Nuclear Information System (INIS)

Reflection coefficients of electromagnetic waves in a nonuniform plasma layer with electrons, positive ions and negative ions, covering a metal surface are investigated by using the finite-difference-time-domain method. It is shown that the reflection coefficients are influenced greatly by the density gradient on the layer edge, layer thickness and electron proportion, i.e., the effect of the negative ions. It is also found that low reflection or high attenuation can be reached by properly choosing high electron proportion, thick plasma layer, and smooth density gradient in the low frequency regime, but sharp density gradient in the high frequency regime. (authors)

2008-07-01

162

Design and Analysis of an Optical Interface Message ...  

Science.gov (United States)

... In 1982 an acousto-optic spectrum analyzer incorporated ... the OPTIMP is the optically controlled optical ... switch that changes the intensity reflectance ...

1993-03-01

163

Elastic plane wave response migration  

Energy Technology Data Exchange (ETDEWEB)

Migration-based methods have been recently proposed to improve the estimation of angle-dependent reflectivity in the presence of complex structures. An anisotropic prestack reverse-time migration is developed to estimate the reflectivity as function of the local illumination angle. This migration method generates four simultaneous images which corresponds to the in-depth (local) plane-wave response for PP, PS, SP and SS reflections, and can be used in a Zoeppritz-based elastic inversion scheme. (author)

1993-07-01

164

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C{sub 3}H{sub 8}O), water (H{sub 2}O) and zinc acetate (Z{sub n}(CH{sub 3}CO{sub 2}){sub 2}) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(lambda) and reflectance R(lambda) spectra. Conjoint optical and thermal ...

2009-10-19

165

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C3H8O), water (H2O) and zinc acetate (Zn(CH3CO2)2) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(?) and reflectance R(?) spectra. Conjoint optical and thermal properties were deduced from the optical ...

2009-10-19

166

Morphological and thermal properties of {beta}-SnS{sub 2} sprayed thin films using Boubaker polynomials expansion  

Energy Technology Data Exchange (ETDEWEB)

In this work, {beta}-SnS{sub 2} thin films have been prepared on glass substrates by the spray pyrolysis technique using an alcohol solution which contains tin chloride (SnCl{sub 4}) and thiourea (SC(NH{sub 2}){sub 2}) as precursors. The structural study shows that {beta}-SnS{sub 2} thin film prepared using optimal experimental conditions: substrate temperature T{sub s} = 280 deg. C and the concentration ratio of sulfur and tin elements in the spray solution x = [S]/[Sn] = 2.5, crystallizes in the hexagonal phase with a strong (0 0 1) X-ray diffraction line. In the same way, microprobe analyses (EPMA) as well as X-ray photoelectron spectroscopy (XPS) show the presence of undiserable phase of SnO{sub 2}. From the transmission and reflectance spectra, the band gap energy is 2.65 eV. On the other hand, the photothermal properties of such films have been studied, the thermal conductivity was K{sub c} = 0.85 W m{sup -1} K{sup -1} and the thermal ...

2009-05-27

167

Morphological and thermal properties of ?-SnS2 sprayed thin films using Boubaker polynomials expansion  

International Nuclear Information System (INIS)

In this work, ?-SnS2 thin films have been prepared on glass substrates by the spray pyrolysis technique using an alcohol solution which contains tin chloride (SnCl4) and thiourea (SC(NH2)2) as precursors. The structural study shows that ?-SnS2 thin film prepared using optimal experimental conditions: substrate temperature Ts = 280 deg. C and the concentration ratio of sulfur and tin elements in the spray solution x = [S]/[Sn] = 2.5, crystallizes in the hexagonal phase with a strong (0 0 1) X-ray diffraction line. In the same way, microprobe analyses (EPMA) as well as X-ray photoelectron spectroscopy (XPS) show the presence of undiserable phase of SnO2. From the transmission and reflectance spectra, the band gap energy is 2.65 eV. On the other hand, the photothermal properties of such films have been studied, the thermal conductivity was Kc = 0.85 W m-1 K-1 and the thermal diffusivity was Dc = 14.5 x 10-6 m2 s-1. The analysis of ?-SnS2 thin ...

2009-05-27

168

MHC-like molecules in some nonmammalian vertebrates can be detected by some cross-reactive xenoantisera.  

DEFF Research Database (Denmark)

Rabbit antisera raised to human and chicken MHC molecules were used to immunoprecipitate cross-reactive molecules from biosynthetically and cell surface-labeled spleen and/or blood cells of representative vertebrate species. Five major points emerged: 1) There were many nonspecific cross-reactions using these techniques, so various criteria were developed to distinguish these from true MHC-like molecules. 2) Only very small subpopulations of immunogen-specific antibodies cross-reacted with MHC-like molecules in other nonmammalian species. These subpopulations were different for each species and even within a species, sometimes being so limited as to behave like alloantisera. This led to a very scattered pattern of true cross-reactions that sometimes failed to reflect the properties of the bulk antibody population. 3) Antisera containing antibodies to class II beta- and class I alpha-chains cross-reacted better and more widely than those to B-G, ...

1990-01-01

169

Interpretation of quasi-Fermi level splitting in Cu(Ga,In)Se2-absorbers by confocally recorded spectral luminescence and numerical modeling  

International Nuclear Information System (INIS)

Spectral room temperature photoluminescence (pl) of polycrystalline Cu(In,Ga)Se2 films (CIGSe) is evaluated with respect to optoelectronic properties and in particular for the determination of the splitting of quasi-Fermi levels (EFn - EFp). For lateral resolution of ? 1 ?m a confocal pl-setup is used. The depth profile of the excess carrier densities determining the rates of radiative transitions strongly govern the spectral pl-shape which has been numerically modeled with a matrix transfer formalism. In this optical approach we discriminate for wave propagation and attenuation in a multilayer system between a plane-wave ansatz and a 3D-spherical formalism, depending on excitation area large or small/similar compared to the thickness of the absorber. In both cases re-absorption of photons in energetic regimes with absorption approaches unity, from which the splitting of the quasi-Fermi levels is preferentially deduced, substantially influence the spectral ...

2009-02-02

170

Genomic analysis of the symbiotic marine crenarchaeon, Cenarchaeumsymbiosum  

Energy Technology Data Exchange (ETDEWEB)

Crenarchaea are ubiquitous and abundant microbial constituents of soils, sediments, lakes and ocean waters, yet relatively little is known about their fundamental evolutionary, ecological, and physiological properties. To better describe the ubiquitous nonthermophilic Crenarchaea, we analyzed the genome sequence of one representative, the uncultivated sponge symbiont, Cenarchaeum symbiosum. C. symbiosum genotypes coinhabiting the same host partitioned into two dominant populations, corresponding to previously described a- and b-type ribosomal RNA variants. Although synthetic, overlapping a- and b-type ribotypes harbored significant genetic variability. A single tiling path comprising the dominant a-type genotype was assembled, and used to explore the biological properties of C. symbiosum and its planktonic relatives. Out of a total of 2,066 predicted open reading frames, 36% were more highly conserved with other Archaea. The remainder ...

2006-06-24

171

A systematic neutron reflectometry study on hydrogen absorption in thin Mg{sub 1-x}Al{sub x} alloy films  

Energy Technology Data Exchange (ETDEWEB)

Various methods for storing hydrogen have been examined in an effort to find ways to store hydrogen in increasingly smaller volumes with decreasing weight of the whole hydrogen storage system. Metal hydrides, in which hydrogen is chemically bound to a metal atom, are considered to be very promising candidates for hydrogen storage because they have high gravimetric and volumetric storage capacities. This study investigated the effect of different magnesium (Mg) and aluminium (Al) ratios on the absorption and desorption properties of thin films. Neutron reflectometry (NR) was used in this study to better understand the absorption and desorption properties of commercially promising hydrogen storage materials. The large negative scattering length of hydrogen atoms changes the reflectivity curve substantially, so that NR can determine the total amount of stored hydrogen as well as the hydrogen distribution along the film normal, ...

2010-10-15

172

Power efficiency for very high temperature solar thermal cavity receivers  

Science.gov (United States)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the ...

1984-01-01

173

Power efficiency for very high temperature solar thermal cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the ...

1984-10-30

174

Improved power efficiency for very-high-temperature solar-thermal-cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positiond in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts radiation from the front of the absorber. ...

1982-04-14

175

Nuclear resonant spectroscopy at Bragg reflections from periodic multilayers: Basic effects and applications  

Science.gov (United States)

A systematic study of the Bragg nuclear resonant reflectivity from periodic multilayers in the energy and time domains is presented. Using the kinematical approach of the general reflectivity theory we describe the basic features of the time evolution of the reflected wave after a pulsed excitation of resonant multilayers by synchrotron radiation. Effects of the collective excitation have been examined such as the shift of quantum beat phases, the interplay between electronic and nuclear subsystem excitations depending on their relative position in a multilayer, the energy and time evolution of standing waves inside a resonant multilayer, and their influence on the reflectivity spectra. The exact expression for the reflectivity by a thin resonant layer placed inside a multilayer structure has been derived. The observed shift of the delayed reflectivity Bragg ...

2005-09-15

176

Near-surface 3D reflections seismic survey; Sanjigen senso hanshaho jishin tansa  

Energy Technology Data Exchange (ETDEWEB)

Faults are being actively investigated across Japan since the Great Hanshin-Awaji Earthquake. Discussed in this report is the application of the 3D near-surface reflection seismic survey in big cities. Data from trenching and drilling is used for the geological interpretation of the surroundings of a fault, and the reflection seismic survey is used to identify the position, etc., of the fault. In this article, when the results obtained from the experimental field are examined, it is found that the conventional 2D imaging reflection survey betrays the limit of its capability when the geological structure is complicated, that the 3D reflection seismic survey, on the contrary, is capable of high-precision imaging and, when augmented by drilling, etc., becomes capable of a more detailed interpretation, and that it also contributes effectively to the improvement of local disaster prevention in big cities. ...

1997-05-27

177

Multilayer reflective coatings for extreme-ultraviolet lithography  

Energy Technology Data Exchange (ETDEWEB)

Multilayer mirror coatings which reflect extreme ultraviolet (EUV) radiation are a key enabling technology for EUV lithography. Mo/Si multilayers with reflectances of 67.5% at 13.4 nm are now routinely achieved and reflectances of 70 2% at 11.4 nm were obtained with MO/Be multilayers. High reflectance is achieved with careful control of substrate quality, layer thicknesses, multilayer materials, interface quality, and surface termination. Reflectance and film stress were found to be stable relative to the requirements for application to EUV lithography. The run-to-run reproducibility of the reflectance peak position was characterized to be better than 0.2%, providing the required wavelength matching among the seven multilayer-coated mirrors used in the present lithography system design. Uniformity of coating was improved to better than 0.5% across 150 mm ...

1998-03-10

178

Deep-crustal structure of the continental margin adjacent to the eastern Aleutian trench  

Energy Technology Data Exchange (ETDEWEB)

Onshore and marine seismic-reflection data obtained near the Trans-Alaskan Crustal Transect (TACT), in the region of the eastern Aleutian trench and lower Cook Inlet, reveal highly reflective midcrustal layering that begins at a depth of 10-15 km within the upper plate of the Aleutian subduction zone. Beneath the continental shelf, midcrustal reflections were recorded over broad areas and occur in subhorizontal bands that are 1 to 3 s thick. The reflections extend beneath complexly deformed late Mesozoic and early Cenozoic accreted rocks that are exposed at the surface. Preliminary interpretation of seismic refraction data indicates that under the shelf the top of the reflections corresponds in depth with a sharp increase in rock velocity, from 5.9 km/s to 6.6 km/s. North and northwest of the shelf, beneath the Chugach and Kenai mountains, midcrustal features dip ...

1990-06-01

179

Genetic Modification of Short Rotation Poplar Biomass Feedstock for Efficient Conversion to Ethanol  

Energy Technology Data Exchange (ETDEWEB)

The Bioenergy Feedstock Development Program, Environmental Sciences Division, Oak Ridge National Laboratory is developing poplars (Populus species and hybrids) as sources of renewable energy, i.e., ethanol. Notable increases in adaptability, volume productivity, and pest/stress resistance have been achieved via classical selection and breeding and intensified cultural practices. Significant advances have also been made in the efficiencies of harvesting and handling systems. Given these and anticipated accomplishments, program leaders are considering shifting some attention to genetically modifying feedstock physical and chemical properties, so as to improve the efficiency with which feedstocks can be converted to ethanol. This report provides an in-depth review and synthesis of opportunities for and feasibilities of genetically modifying feedstock qualities via classical selection and breeding, marker-aided selection and breeding, and genetic transformation. ...

2000-08-30

180

Comparison of histological findings and parathyroid scintigraphy in hemodialysis patients with secondary hyperparathyroid glands  

International Nuclear Information System (INIS)

The objective of this study was to determine the usefulness of parathyroid scintigraphy in histological estimation for secondary hyperparathyroidism (2HPT) using Tc-99m sestamibi or Tc-99m tetrofosmin. Tc-99m sestamibi (MIBI) and Tc-99m tetrofosmin (Tetro) parathyroid imaging following double-phase study, magnetic resonance imaging (MRI), and ultrasound were performed on 14 patients with 2HPT. All patients underwent parathyroidectomy. The uptake of two tracers in parathyroid areas was compared with the histopathologic findings. Forty-nine parathyroid glands were surgically explored and histologically proven to be hyperplastic. Of these, 42 were diagnosed with nodular type (N-type) hyperplasia, and 7 with diffuse type (D-type) hyperplasia. MIBI and Tetro parathyroid imagings detected 34 and 35 parathyroid glands, respectively. The sensitivity of MIBI was determined to be 76.2% (32/42) for N-type, and 28.6% (2/7) for D-type. The sensitivity of Tetro was determined to ...

2005-04-01

181

The use of SMARTeR stents in patients with biliary obstruction  

Energy Technology Data Exchange (ETDEWEB)

AIM: The purpose of the study was to evaluate the percutaneous use of the new nitinol SMARTeR stents in patients with biliary obstruction. MATERIALS AND METHODS: Four stents were placed in three patients percutaneously under ultrasound and fluoroscopic guidance. RESULTS: The deployment of the stents was successful in all three patients. All stents maintained their patency and position after short-term follow-up. CONCLUSION: The nitinol SMARTeR stent is useful in the management of patients with biliary obstruction although accurate placement across the ampulla was found to be technically more difficult than with the Wallstent. Larger, long-term follow-up studies are required to evaluate the long-term patency of these new devices.

2004-03-01

182

Solid suspension in stirred tanks: UVP measurements and CFD simulations  

British Library Electronic Table of Contents (United Kingdom)

Abstract Suspension of solids in stirred reactor is widely used for catalytic reactions, dissolution, etc. Quality of solid suspension is an important parameter required for the reliable design, optimum performance, and scale up of the system. Quality of suspension depends on local characteristics of solid velocity and hold up profiles. The present work was focused on investigating quality of solid suspension using ultrasound velocity profiler (UVP) measurements and CFD simulations. The slip velocity measurements carried out with UVP were used to evaluate different drag correlations used in CFD simulations. Results discussed in this work would be useful for extending the applications of CFD models for simulating large stirred slurry reactors.

2011-01-01

183

Real time automatic discriminating of ultrasonic flaws  

International Nuclear Information System (INIS)

This paper is concerned with the real time automatic discriminating of flaws from two categories; i. cracks (planar defect) and ii. Non-cracks (volumetric defect such as cluster porosity and slag) using pulse-echo ultrasound. The raw ultrasonic flaws signal were collected from a computerized robotic plane scanning system over the whole of each reflector as the primary source of data. The signal is then filtered and the analysis in both time and frequency domain were executed to obtain the selected feature. The real time feature analysis techniques measured the number of peaks, maximum index, pulse duration, rise time and fall time. The obtained features could be used to distinguish between quantitatively classified flaws by using various tools in artificial intelligence such as neural networks. The proposed algorithm and complete system were implemented in a computer software developed using Microsoft Visual BASIC 6.0 (author)

2009-07-20

184

Perioperative Care of a Child with Transposition of the Great Arteries  

British Library Electronic Table of Contents (United Kingdom)

Opinion statement Because a minority of patients with D-transposition of the great arteries are diagnosed in utero by ultrasound, most present after delivery with cyanosis. In the absence of apparent lung disease, cyanotic neonates suspected of having a cardiac lesion should be immediately transferred to an intensive care unit at a pediatric tertiary care center for monitoring, resuscitation, and to define the cardiac anatomy and physiology. A prostaglandin E-1 infusion is usually initiated to maintain ductal patency and promote intra-cardiac mixing. In the past, balloon atrial septostomy (BAS) was routinely performed to enlarge the atrial septal defect and improve intra-cardiac mixing while the infants awaited surgery. Recent literature has reported an increase risk of stroke in neonates ...

2011-01-01

185

MRI imaging of fetal neck masses with airway compromise: utility in delivery planning  

International Nuclear Information System (INIS)

We present two cases of fetal neck masses that were initially diagnosed by ultrasound and further evaluated with prenatal MRI. MRI findings aided in further delineating the neck masses, increasing confidence in the final diagnosis (cervical teratoma and cystic hygroma). With the fetal airway typically filled with fluid that is of high signal on T2-weighted sequences, MRI images in three planes could identify whether the fetal larynx and trachea were partially or completely compressed by the neck tumor. This information was particularly useful in determining if a controlled delivery such as ex utero intrapartum treatment (EXIT) was necessary and aided the surgeons in planning their approach to establishing airway control in the delivery room. (orig.)

2001-10-01

186

Image-guided percutaneous cryotherapy for the management of gynecologic cancer metastases  

British Library Electronic Table of Contents (United Kingdom)

Objective To report the clinical response to image-guided percutaneous cryotherapy (IPC) for the palliative management of localized metastases in patients with gynecologic malignancies. Methods Institutional review board approval and patient consent were obtained. Gynecologic oncology patients were identified from our institution's cryotherapy database from August 2003 to August 2007. Cryotherapy was performed with 2.4?mm diameter probes (Endocare, Irvine, CA) with ultrasound or computerized tomography (CT) guidance under conscious sedation and local anesthesia. Follow-up was conducted by imaging studies and clinical encounters, using Response Evaluation Criteria in Solid Tumors (RECIST criteria). Results Twenty-eight ablation sessions were performed for 41 metastatic foci in 15 patients w...

2008-01-01

187

Hepatosplenic T-cell lymphoma is a distinct rare entity: Diagnosis by fine-needle aspiration cytology  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this brief report, we have described the fine-needle aspiration cytology (FNAC) of a hepatosplenic T-cell lymphoma (HSTCL) in a 60-year-old female patient. The patient complained of fever and heaviness of left upper abdomen. Ultrasound-guided FNAC of the spleen showed immature lymphoid cells, and a diagnosis of primary non-Hodgkin lymphoma of spleen was offered. Subsequently, the patient underwent splenectomy and wedge biopsy of liver that confirmed the cytological diagnosis. The lymphoma cells were positive for CD3 immunostain. Primary hepatosplenic T-cell lymphoma is a rare entity and may often pose diagnostic problems on FNAC. Diagn. Cytopathol. 2010. 2010 Wiley-Liss, Inc.

2011-01-01

188

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 adjunct or second-line imaging modality. ...

2002-08-01

189

Early-stage focal nodular hyperplasia: US/CT/MR features correlated with histology  

Energy Technology Data Exchange (ETDEWEB)

Two cases of focal nodular hyperplasia (FNH), in which ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MR) studies detected an atypical hemorrhagic pattern associated with an intrahepatic arterio venous malformation (AVM) around the growths, are presented. In both cases, histology demonstrated a very early regenerative stage and necrotic-hemorrhagic areas within the lesions. In these cases, the analysis of radiological findings, surgical specimens and histology seemed to confirm the pathogenetic hypothesis suggested by Wanless: in normal liver parenchyma, a ``blood steal`` phenomenon due to congenital or acquired intrahepatic AVM could cause ischemic damage, appearing as a hemorrhagic necrotic area, the extent of which depends on the degree of residual portal supply. (orig.)

1994-02-01

190

Delaying the superficial inferior epigastric artery flap: A solution to the problem of the small calibre of the donor artery  

British Library Electronic Table of Contents (United Kingdom)

Background: Superficial inferior epigastric artery (SIEA) flap has a great advantage over other flaps of the area, that is, readily non-existent donor-site problems. The main reason why the SIEA flap has never been extensively used in breast reconstruction is the small diameter and variable anatomy of its donor artery. This study presents a possibility of enlarging the SIEA diameter using the delay-phenomenon mechanism. Methods: A prospective clinical study of 26 patients was undertaken. Prior to surgery, ultrasound examinations were performed, measuring the diameter of SIEA and the velocity of blood flow in SIEA. The ipsilateral deep inferior epigastric artery (DIEA) was then ligated in all patients who had a measurable SIEA preoperatively. Two weeks later, measurements were repeated. The...

2011-01-01

191

Clinical and metabolic characteristics of polycystic ovary syndrome without polycystic ovary: a pilot study on Chinese women  

British Library Electronic Table of Contents (United Kingdom)

Objective To demonstrate clinical features of a patient subgroup presenting with polycystic ovary syndrome (PCOS) without polycystic ovary morphology. Design Retrospective study. Setting Hospital-based IVF center. Patient(s) In the present study, 876 PCOS patients were selected from women who visited the Reproductive Medicine Center at Shandong Provincial Hospital, Shandong University, between September 2004 and October 2006. Women with PCOS were divided into two groups based on ultrasound image: group A, PCOS patients with classic polycystic ovary (n = 800); group B, PCOS patients without polycystic ovary morphology (n = 76). The following available data were analyzed in the large cohort of women: body height, weight, waistline, hip circumference, hirsutism scores, family history, serum s...

2008-01-01

192

A Study on TOFD Inspection Using Phased Array Ultrasonic Technique  

Energy Technology Data Exchange (ETDEWEB)

The techniques in order to measure the depth of defect in weldment and structure accurately have been developed. Many researches have made efforts to develop the methods for the accurate depth sizing of defect. TOFD is known as the most accurate method of various methods for measuring depth sizing. However, there is a possibility to miss defects because of the limitation of beam coverage for the ultrasound incident angle. In this study, the results for detectability and depth sizing using phased array ultrasonic technique for thick body were compared with those of conventional TOFD technique. It was experimentally confirmed that the phased array ultrasonic TOFD technique gives good detectability and accurate depth measurement for the various types of defects. The phased array ultrasonic TOFD technique developed in this study will contribute to increase the inspection reliability in thick component such as the pressure vessel of power generation industry

2005-08-15

193

High pressure study of AlP: Transformation to a metallic NiAs phase  

Science.gov (United States)

The crystal structure and optical reflectivity of AlP has been studied in a diamond anvil cell using energy dispersive x-ray diffraction to 43 GPa and micro-optical reflectance spectroscopy to 36 GPa. AlP undergoes a first order phase transformation from zincblende to a NiAs structure which exhibits metallic reflectivity in the near-infrared. The decrease in volume on transformation is 17%[plus minus]1%. The transformation is reversible but has large hysteresis. The equilibrium transformation pressure is 9.5[plus minus]5 GPa.

1994-12-01

194

Educational research in Mainland China: current situation and developmental trends  

British Library Electronic Table of Contents (United Kingdom)

The influence of Confucian culture in Chinese Mainland China is reflected in the current situation and contextual trends of educational research content of educational thought of Confucianism, educational issues grounded on theoretical views of Confucianism, and the influence of the inclusiveness of Confucianism. In terms of research method, the current situation of educational research is reflected in empirical research whose methods value the construction of the metaphysical theoretical system, the guiding role of educational theories for educational reform practice, and research that enriches the literature. In terms of research value, the current situation of educational research is reflected in studies that focus on human nature, human relations, thoughts, willpower, emotion, human ri...

2011-01-01

195

Visible Earth: Haitian Deforestation - Visible Earth - NASA  

Science.gov (United States)

Jun 8, 2006 ... It also reflects the large amount of deforestation that has occurred on the Haitian side of the border. One can easily see from satellite imagery ...

196

So /s/ Julia A. Whitt /s/JeHrey S. Jackson - + MSFC FOIA Home - NASA  

Science.gov (United States)

NETWORK SECURITY, is revised to reflect, as item "g", incorporation ..... The Contractor shall provide support for the network security of the ...

197

Remote Sensing Tutorial ... - The Remote Sensing Tutorial - NASA  

Science.gov (United States)

The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...

198

Relationship of Optical Coating on Thermal Radiation ...  

Science.gov (United States)

drical Enclosures Using a Numerical Ray Tracing Technique. NASA. TM-I02527, 1990 . Buckley, H.: Radiation from the Interior of a Reflecting Cylinder. Philos. ...

199

Numerical Simulation of Quarry Source and Reflection ...  

Science.gov (United States)

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

1990-08-01

200

N94- 31026 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

in early 1992 from Lord Corporation, were also found. For both the reflective and absorptive polyurethanes, the fresh paint fluoresces significantly ...

201

Kramers-Kronig Analysis of Infrared Reflectance Spectra for Quaternary In_xAl_yGa_1_-_x_-_yN Alloy  

International Nuclear Information System (INIS)

In this paper, a Kramers-Kronig (KK) analysis of infrared (IR) reflectance spectrum of quaternary In_0_._0_1Al_0_._0_6Ga_0_._9_3N film grown by molecular beam epitaxy (MBE) is reported. The infrared measurement is performed in the reflection mode at an incident angle of 15 degree sign by Fourier transform infrared (FTIR) spectroscopy at T = 300 K. The Kramers-Kronig analysis of the reflectivity data has been used to obtain the real and imaginary parts of the index of refraction (n and k), and the real and imaginary parts of the dielectric response function (#epsilon#' and #epsilon#') of the materials. Finally, the transverse optical and longitudinal optical phonons for quaternary In_xAl_yGa_1_-_x_-_yN were obtained.

2010-07-07

202

Human climatic comfort within enclosing walls with varying strengths of infrared radiation reflection  

Energy Technology Data Exchange (ETDEWEB)

An experiment lasting a number of hours was carried out with 6 men under standardised climate chamber conditions to find out to what extent wallpaper that reflects about 65-75% in the infra-red range by comparison with normal wallpaper that reflect only 3-5% of heat, has measurable positive effects on the thermoregulation of the human body and the human sensation of temperature. The measurements of skin temperature and heat flow intensity in the deeper areas of the body and the periphery, and metabolic heat conversion measurements (indirect calorimetry) confirm that infra-red reflection of the heat irradiated from the body lead to a measurable heat recovery on the body surface with a reduction of metabolic conversion. It was proved that it is possible to reduce the average room temperature by up to 4 K whilst maintaining the same degree of thermal comfort, which corresponds to a 20% saving in heating energy. (orig./BWI).

1985-06-01

203

GALAXY EVOLUTION EXPLORER (GALEX) GUEST ... - GALEX - NASA  

Science.gov (United States)

star evolution, globular cluster structure and evolution, massive stars, supernova remnants, reflection nebulae, interstellar dust, structure of the ISM, ...

204

CIVIL USES OF REMOTELY PILOTED AIRCRAFT' - NASA Technical Report ...  

Science.gov (United States)

to, an altitude of 5000 ft (1500 m) AGL and f4.ies tight circles. If link has ...... The learning-curve effect reflects the observable ...

205

Association Between Wasted Pressure Effort and Left Ventricular Hypertrophy in Hypertension: Influence of Arterial Wave Reflection  

British Library Electronic Table of Contents (United Kingdom)

BackgroundWave reflection during the systole increases left ventricular (LV) pressure, tension-time index (TTI) and myocardial oxygen requirement. The purpose of this study was to extract that component of extra myocardial oxygen requirement that is due to early systolic wave reflection, define it as wasted effort (?Ew), and examine its relationship to LV hypertrophy (LVH).MethodsRadial artery pressure waveforms were recorded using applanation tonometry and central aortic waveforms generated in 98 patients with untreated hypertension. Aortic augmentation index (AIa), wave reflection amplitude (i.e., aortic augmented pressure (AG)) and systolic duration (ED?Tr), ejection duration (ED) and round-trip travel time of the pressure wave (Tr) were calculated from the aortic waveform, a...

2008-01-01

206

Utilization of smooth models for seismic data tomographic inversion  

Energy Technology Data Exchange (ETDEWEB)

Reflection tomography allows in theory the determination of the velocity distribution and the reflector geometries in the subsurface from the travel times of the seismic waves. The solution of the inverse problem is the model (velocity distribution and reflectors) that minimizes the misfits between observed travel times and travel times computed by raytracing (the forward problem). Two representations of the velocity field are generally used: blocky models (discontinuous) and smooth models. The object of this thesis is the study of tomography with smooth models which offer interesting properties at a practical level as well as at a mathematical and numerical level. We propose an original formulation of the inverse problem which allow the integration of a priori information adapted to smooth models. This formulation assures the existence, the uniqueness and the stability of the solution of the linearized inverse problem. The non-linear inverse ...

1995-03-01

207

Ultracold neutrons  

International Nuclear Information System (INIS)

In 1959 Zeldovich pointed out to the possibility of storage in a closed vessel of very slow neutrons with energies below less than or equal to 10"-"7 eV noting that one may achieve the storage time up to the lifetime of a free neutron before #beta#-decay (approx.10"3 sec). This possibility is due to the effective repulsing potential which describes the interaction of slow neutrons with many substances employing a strong suppression of inelastic processes in the reflection of ultracold neutrons (UCN). In a series of experiments beginning 1968 the effective methods were developed of obtaining pure UCN beams from the maxwellian spectrum of thermal neutrons. The UCN beams of intensity about 10"3 n/sec and density up to 10"2 n/liter were obtained at the reactors with thermal neutron flux of 5 x 10"1"3 n/cm"2 sec. Such UCN beam parameters allow to measure easily the UCN storage time in different vessels and under different conditions. Maximum UCN storage time achieved in ...

1976-07-06

208

The characteristics of coal reservoir pores and coal facies in Liulin district, Hedong coal field of China  

Energy Technology Data Exchange (ETDEWEB)

The composition, rank, coal facies, and coal pore structure characteristics of 15 coal samples were investigated systemically using methods of lithotype analysis, maceral analysis, proximate analysis, mercury porosimetry analysis, and nitrogen adsorption analysis. These samples were directly collected from the working faces of No.4, 8, 9 seams in Liulin district, eastern margin Ordos Basin, China. Four types of paleoenvironment including a wet forest swamp, an intergradation forest swamp, a drained forest swamp, and a fresh-water peat swamp were distinguished by lithotype and merceral analysis. An R-cluster analysis was performed to demonstrate the correlations between the coal facies and the pore structures. The results showed that coal rank is the primary factor affecting the development of micropores and transition pores, whereas coal facies control the development of seepage pores in similar coalification conditions, especially in a local district and in a seam. This work suggests ...

2010-02-01

209

Subseabed disposal: systematic application of the site qualification plan  

Energy Technology Data Exchange (ETDEWEB)

Two criteria, geologic stability and barrier effectiveness, form the basis of the Subseabed Disposal Program's site qualification plan to evaluate the ocean basins and identify those regions having characteristics most favorable for containment of radioactive waste. Stability criteria are used to define those regions least likely to be disturbed by tectonic forces or oceanographic changes during the lifetime of a waste repository. Barrier criteria define those lithologies most likely to form an effective barrier to the release of radionuclides. Two north Pacific regions and three north Atlantic regions (PAC I and II and ATL I, II, and III, respectively) have thus far been selected for further investigation based on the site qualification plan. The PAC I region, centered on the Shatsky Rise in the northwest Pacific, has been subdivided into areas and locations on the basis of an exhaustive review of data available in the archives of national and international agencies and ...

1982-01-01

210

Structural and optical investigations of sodium europium carbonate Na{sub 3}Eu(CO{sub 3}){sub 3}  

Energy Technology Data Exchange (ETDEWEB)

The crystal structure and the luminescence properties of a new carbonate, Na{sub 3}Eu(CO{sub 3}){sub 3}, are presented. Na{sub 3}Eu(CO{sub 3}){sub 3} is orthorhombic, acentric, Ama2, Z = 4; a = 9.942(2) {angstrom}, b = 11.024(3) {angstrom}, c = 7.147(2) {angstrom}; R = 0.019, R{sub w} = 0.051, 2374 unique reflections. The anionic subnetwork is built up from the stacking of {open_quotes}standing on edge{close_quotes} and {open_quotes}flat lying{close_quotes} carbonate layers into which Na{sup +} and Eu{sup 3+} ions are inserted. The symmetry of the EuO{sub 9} polyhedra is C{sub s}. The Eu{sup 3+} ions are inserted. The symmetry of the EuO{sub 9} polyhedra is C{sub s}. The Eu{sup 3+} luminescence technique confirms the presence of a unique low symmetry site for the rare earth atom. The electrostatic crystal field (cf) effects on the {sup 7}F multiplet are evaluated on the basis of the phenomenological cf theory. The simulation using C{sub 2v} ...

1997-08-01

211

Single protein omission reconstitution studies of tetracycline binding to the 30S subunit of Escherichia coli ribosomes  

Energy Technology Data Exchange (ETDEWEB)

In previous work the authors showed that on photolysis of Escherichia coli ribosomes in the presence of ({sup 3}H)tetracycline (TC) the major protein labeled is S7, and they presented strong evidence that such labeling takes place from a high-affinity site related to the inhibitory action of TC. In this work they use single protein omission reconstitution (SPORE) experiments to identify those proteins that are important for high-affinity TC binding to the 30S subunit, as measured by both cosedimentation and filter binding assays. With respect to both sedimentation coefficients and relative Phe-tRNA{sup Phe} binding, the properties of the SPORE particles they obtain parallel very closely those measured earlier, with the exception of the SPORE particle lacking S13. A total of five proteins, S3, S7, S8, S14, and S19, are shown to be important for TC binding, with the largest effects seen on omission of proteins S7 and S14. Determination of the protein compositions of ...

1990-06-05

212

Physical and electrochemical characterization of CdS hollow microspheres prepared by a novel template free solution phase method  

International Nuclear Information System (INIS)

Novel CdS hollow microspheres have been successfully synthesized via a facile template-free solution-phase reaction from cadmium nitrate and thioacetamide precursors. The morphology of CdS hollow microspheres depends strongly on the ratio between the precursors, cadmium nitrate to thioacetamide ratio. The physical properties of the hollow microspheres have systematically been studied by different characterization methods. The stoichiometry of the hollow microspheres studied by the energy dispersive X-ray diffraction spectroscopy confirmed that the synthesized CdS hollow microspheres are nearly stoichiometric bulk like CdS. The morphology of the hollow microspheres studied by high resolution scanning electron microscopy and transmission electron microscopy observations showed that the CdS hollow microspheres of the size of 2.5 ?m have hollow structure and are constructed by several nanoparticles of the size between 30 and 40 nm. The UV-visible diffuse ...

2010-12-15

213

Optical properties of crystalline and non-crystalline iron oxide thin films deposited by spray pyrolysis  

International Nuclear Information System (INIS)

Crystalline and non-crystalline iron oxide (#alpha#-Fe_2O_3) thin films were obtained by spray pyrolysis onto glass substrate at different temperatures. The results of X-ray diffraction showed that with increasing the deposition time, the film structure changed from non-crystalline to crystalline at the same substrate temperature. At different substrate temperatures and low deposition times (5 min), iron oxide appears almost in non-crystalline form. With rising the substrate temperature and deposition time, the crystallinity was improved. The effect of substrate temperature as well as deposition time on the optical features (absorption coefficient and bandgap) and optical constants of these films has been investigated. Optical constants of the films were determined from spectrophotometric measurement of reflectance and transmittance. Analysis of the results showed that, for non-crystalline iron oxide films of different thicknesses (76-118 nm) deposited at ...

2004-06-30

214

Optical modeling of compound CuInS{sub 2} using relative dielectric function approach and Boubaker polynomials expansion scheme BPES  

Energy Technology Data Exchange (ETDEWEB)

The ternary compound CuInS{sub 2} is attractive for solar cells due to its band gap of 1.54 eV which borders the optimum value necessary for conversion of a solar spectrum. Recently, works on thin film cells based on this material (ZnO/CuInS{sub 2}) has been reported to show efficiency as high as 11.4%. In this paper, the orientation and the morphology of CuInS{sub 2} sprayed films are determined by the means of X-ray diffraction and scanning electron microscopy. Sprayed CuInS{sub 2} films deposited onto a transparent Pyrex substrate with standard fabrication parameters show a chalcopyrite structure with a preferential orientation (1 1 2). A model based on the calculation of the relative dielectric function {epsilon} has been performed in order to obtain the profile of variation of this parameter and to understand the optical behavior of this material via its transmittance and reflectance in visible and near-infrared regions (0.35-2.5 {mu}m). In the same way, ...

2009-07-29

215

Optical modeling of compound CuInS2 using relative dielectric function approach and Boubaker polynomials expansion scheme BPES  

International Nuclear Information System (INIS)

The ternary compound CuInS2 is attractive for solar cells due to its band gap of 1.54 eV which borders the optimum value necessary for conversion of a solar spectrum. Recently, works on thin film cells based on this material (ZnO/CuInS2) has been reported to show efficiency as high as 11.4%. In this paper, the orientation and the morphology of CuInS2 sprayed films are determined by the means of X-ray diffraction and scanning electron microscopy. Sprayed CuInS2 films deposited onto a transparent Pyrex substrate with standard fabrication parameters show a chalcopyrite structure with a preferential orientation (1 1 2). A model based on the calculation of the relative dielectric function ? has been performed in order to obtain the profile of variation of this parameter and to understand the optical behavior of this material via its transmittance and reflectance in visible and near-infrared regions (0.35-2.5 ?m). In the same way, considering the inhomogeneous material ...

2009-07-29

216

Optical absorptance and thermomodulation studies of several A-15 compounds  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this work was to investigate the optical properties of several high T/sub c/ compounds in the form of sputtered films. The measurements are used toward this end: optical absorptance (using a calorimetric technique near 4.2K), which yields (after Kramers-Kronig analysis) the complex dielectric function, and thermoreflectance (which measures the change in reflectance in the optical range when a 1 to 10/sup 0/K temperature wave is applied), performed at two ambient temperatures (80 and 300/sup 0/K), yielding the differential dielectric function. The sputtered films included Nb/sub 3/Ge, Nb/sub 3/Al, V/sub 3/Ga and Nb/sub 3/Ir. It is noted that Nb/sub 3/Ir is not a high T/sub c/ superconductor. The thermoreflectance on the bulk samples V/sub 3/Si, V/sub 3/Ge and single crystal Cr/sub 3/Si were not performed because the samples were not in the form of thin films. The thermomodulation studies are correlated with the absorptance ...

1983-06-01

217

Optical absorptance and thermomodulation studies of several A-15 compounds  

International Nuclear Information System (INIS)

The purpose of this work was to investigate the optical properties of several high T/sub c/ compounds in the form of sputtered films. The measurements are used toward this end: optical absorptance (using a calorimetric technique near 4.2K), which yields (after Kramers-Kronig analysis) the complex dielectric function, and thermoreflectance (which measures the change in reflectance in the optical range when a 1 to 10_0K temperature wave is applied), performed at two ambient temperatures (80 and 300_0K), yielding the differential dielectric function. The sputtered films included Nb"3Ge, Nb"3Al, V"3Ga and Nb"3Ir. It is noted that Nb"3Ir is not a high T/sub c/ superconductor. The thermoreflectance on the bulk samples V"3Si, V"3Ge and single crystal Cr"3Si were not performed because the samples were not in the form of thin films. The thermomodulation studies are correlated with the absorptance measurements in comparison to band structure ...

218

New materials for batteries and fuel cells. Materials Research Society symposium proceedings, Volume 575  

Energy Technology Data Exchange (ETDEWEB)

This proceedings volume is organized into seven sections that reflect the materials systems and issues of electrochemical materials R and D in batteries, fuel cells, and capacitors. The first three parts are largely devoted to lithium ion rechargeable battery materials since that electrochemical system has received much of the attention from the scientific community. Part 1 discusses cathodes for lithium ion rechargeable batteries as well as various other battery systems. Part 2 deals with electrolytes and cell stability, and Part 3 discusses anode developments, focusing on carbon and metal oxides. Part 4 focuses on another rechargeable system that has received substantial interest, nickel/metal hydride battery materials. The next two parts discuss fuel cells--Part 5 deals with Proton Exchange Membrane (PEM) fuel cells, and Part 6 discusses oxide materials for solid oxide fuel cells. The former has the benefit of operating around room temperature, whereas the ...

2000-07-01

219

Magnetic properties of Nd_2CuO_4-type R_2CuO_4 (R=Y, Dy, Ho, Er, Tm) synthesized under high pressure: Weak ferromagnetism of Y_2CuO_4  

International Nuclear Information System (INIS)

Magnetization of R_2CuO_4 (R=Y, Dy, Ho, Er, Tm) crystallizing in the Nd_2CuO_4-type (T') structure has been measured between 4 and 300 K. In Y_2CuO_4 antiferromagnetic ordering of Cu"2"+ spins at 260 K has been detected clearly, without being interfered with by the paramagnetic contribution of rare-earth elements as in the other compositions. Weak ferromagnetic behavior with a moment of 9x10"-"4 #mu#_B/Cu accompanies the antiferromagnetic transition. Dy"3"+, Ho"3"+, Er"3"+, and Tm"3"+ ions obey the Curie-Weiss law at relatively high temperatures, and the effective moments are in good agreement with the values anticipated from their lowest multiplet levels. Various types of deviations from the law occur at low temperatures. Specifically, a sharp kink possibly suggesting antiferromagnetic ordering of the Dy"3"+ moments has been found at 7 K. Anomalies around 200 K for Ho_2CuO_4 and Er_2CuO_4 reflect the weak ferromagnetic contribution of the CuO_2 lattice.

1990-10-01

220

Large orbital magnetic moment and its quenching in the itinerant uranium intermetallic compounds UTGa_5 (T=Ni, Pd, Pt)  

International Nuclear Information System (INIS)

The crystal structure, lattice strain due to the antiferromagnetic ordering, and magnetic form factor in the itinerant 5f compounds UTGa_5 (T=Ni, Pd, Pt) have been studied by neutron scattering. High-resolution powder diffraction revealed that the tetragonality of the U-Ga layers increases down to the series of the transition metal element T. The integrated intensities of the antiferromagnetic reflections can be well explained with the Neel-type structure for UNiGa_5, whereas UPtGa_5 has the antiferromagnetic stacking of the ferromagnetically ordered uranium moments in the c plane. In both compounds the uranium moments orient along the c axis with moments of 0.75(5) and 0.32(5) #mu#_B for UNiGa_5 and UPtGa_5, respectively. No magnetic peak could be observed in the powder diffraction pattern of UPdGa_5 due to the small magnetic moment less than the experimental sensitivity. The orbital contributions in the magnetic form factor are reduced from the free-ion value, ...

2003-12-01

221

Improved eddy-current inspection for steam generator tubing  

International Nuclear Information System (INIS)

Computer programs have been written to allow the analysis of different types of eddy-current probes and their performance under different steam generators test conditions. The probe types include the differential bobbin probe, the absolute bobbin probe, the pancake probe and the reflection probe. The generator test conditions include tube supports, copper deposits, magnetite deposits, denting, wastage, pitting, cracking, and intergranular attack. These studies are based mostly on computed values, with the limited number of test specimens available used to verify the computed results. The instrument readings were computed for a complete matrix of the different test conditions, and then the test conditions determined as a function of the readings by a least-squares technique. A comparison was made of the errors in fit and instrument drift for the different probe types. The computations of the change in instrument reading due to the defects have led to an inversion ...

1990-03-01

222

Imaging of reflection seismic and radar wavefields: Monitoring of steam-heated oil reservoirs and characterization of nuclear waste repositories  

Energy Technology Data Exchange (ETDEWEB)

A new three-dimensional (3D) acoustic modelling method was developed using a first-order hyperbolic wave system which was solved with explicit finite dfferences. The numerical solution of the 3D wave system provides a useful method for simulating evolution of a pressure field corresponding to compressional type waves. Existing two-dimensional (2D) elastic modelling algorithms were modified and fine-tuned for computationally efficient and realistic wave propagation simulations in complex structures. An original formulation of the 3D reverse time migration method was developed which is very accurate, does not suffer from unwanted evenescent energy, can image dips beyond 90{degree}, and does not generate multiple energy. Two case studies were performed that involved steam stimulation projects in the Cold Lake deposit. Simulations were performed during different phases of the steam stimulation process to examine the relation between reservoir properties and conditions ...

1994-12-31

223

Electronic structure of KTiOAsO_4: A comparative study by the full potential linearized augmented plane wave method, X-ray emission spectroscopy and X-ray photoelectron spectroscopy  

International Nuclear Information System (INIS)

First-principles self-consistent band-structure calculations of potassium titanyl arsenate, KTiOAsO_4 (KTA), have been made using the full potential linearized augmented plane wave (FP-LAPW) method. Total and partial densities of states of the constituent atoms of KTA have been derived. The results obtained show that the valence band of KTA is dominated by contributions of the O 2p-like states, while the Ti 3d-like states are the main contributors into the conduction band of the compound. Additionally, the FP-LAPW calculations have revealed that potassium atoms are highly ionized in KTA. In the present work, the X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) methods were also employed to investigate experimentally the electronic structure of potassium titanyl arsenate. For the mentioned compound, the XES K Ll, Ti L#alpha#, As K#beta#_2 and O K#alpha# bands reflecting the valence K s-, Ti s,d-, As p- and O p-like states, respectively, ...

2009-05-27

224

Electronic instabilities and the martensitic transition in A-15 compounds  

International Nuclear Information System (INIS)

The structural transition and anomalous properties of the high temperature A-15 superconductors have been investigated from two different standpoints. The first is a Landau theory based on Gorkov's physical model of a Peierls-like charge density wave (CDW) transition involving electronic CDW order parameters coupled to phonon coordinates. Pretransition elastic anomalies, softening of the [1 anti 10] transverse ([1 anti 10] polarized) phonon, sublattice distortions, variation of transition temperature with stress and alloying and other effects have been accurately predicted, and a detailed comparison is made with experimental results. Central peaks in neutron scattering are shown to be non-dynamic in nature and no pretransition forbidden (300) reflection is predicted. The GAMMA_1_2 optic mode does not go soft at the transition, though its frequency is expected to be temperature dependent right up to room temperature. A tight binding, two (3-D) ...

225

Development of 2-D velocity structure model input tool  

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. Since the FEM (Finite Element Method) ray tracing we have developed goes well the inverse velocities structure, we can apply the inversion problem to complex geological model. For the convenience of ...

1996-12-01

226

Deficiency of the housekeeping gene hypoxanthine-guanine phosphoribosyltransferase (HPRT) dysregulates neurogenesis.  

Science.gov (United States)

Neuronal transcription factors play vital roles in the specification and development of neurons, including dopaminergic (DA) neurons. Mutations in the gene encoding the purine biosynthetic enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) cause the resulting intractable and largely untreatable neurological impairment of Lesch-Nyhan disease (LND). The disorder is associated with a defect in basal ganglia DA pathways. The mechanisms connecting the purine metabolic defect and the central nervous system (CNS) phenotype are poorly understood but have been presumed to reflect a developmental defect of DA neurons. We have examined the effect of HPRT deficiency on the differentiation of neurons in the well-established human (NT2) embryonic carcinoma neurogenesis model. We have used a retrovirus expressing a small hairpin RNA (shRNA) to knock down HPRT gene expression and have examined the expression of a number of transcription factors essential for neuronal ...

2009-08-11

227

Combined Estimation of Hydrogeologic Conceptual Model, Parameter, and Scenario Uncertainty with Application to Uranium Transport at the Hanford Site 300 Area  

Energy Technology Data Exchange (ETDEWEB)

This report to the Nuclear Regulatory Commission (NRC) describes the development and application of a methodology to systematically and quantitatively assess predictive uncertainty in groundwater flow and transport modeling that considers the combined impact of hydrogeologic uncertainties associated with the conceptual-mathematical basis of a model, model parameters, and the scenario to which the model is applied. The methodology is based on a n extension of a Maximum Likelihood implementation of Bayesian Model Averaging. Model uncertainty is represented by postulating a discrete set of alternative conceptual models for a site with associated prior model probabilities that reflect a belief about the relative plausibility of each model based on its apparent consistency with available knowledge and data. Posterior model probabilities are computed and parameter uncertainty is estimated by calibrating each model to observed system behavior; prior parameter estimates ...

2007-07-30

228

Characterization of a time-of-flight mass spectrometer and its applications in the study of solid surfaces; Charakterisierung eines Flugzeitmassenspektrometers und seine Anwendungen in der Festkoerperoberflaechenuntersuchung  

Energy Technology Data Exchange (ETDEWEB)

The object and the purpose of the present work was to develop, to assemble and to start running a new TOF (time of flight) mass spectrometer for imaging SNMS analytic which is optimized for the analysis of highly molecular secondary ions. The most important purpose was the characterization of the TOF mass spectrometer. The obtained mass spectra of indium, tantalum and silver clusters reflect the excellent properties of the TOF mass spectrometer for the detection of large clusters with good detection efficiency up to masses of 16000 amu. The possibility of the deflection of selected saturated atom and cluster peaks serves for further improvement of the detection efficiency for large molecules. The accessible mass resolution was determined to be of the order of m/{delta}m=1000 in the high mass region. Numerous measurements were carried out to characterize the useful yield of this spectrometer. For a best possible adaptation of the TOF mass ...

2006-12-21

229

CP property of the Higgs at the #gamma##gamma# colliders using tt-bar production  

International Nuclear Information System (INIS)

We present results of an investigation to study CP violation in the Higgs sector in tt-bar production at a #gamma##gamma#-collider, via the process #gamma##gamma# #-># #phi# #-># tt-bar where the #phi# is a scalar with indeterminate CP parity. The study is performed in a model independent way parametrising the CP violating couplings in terms of six form factors #left brace#R(S_#gamma#), T(S_#gamma#), R(P_#gamma#), T(P_#gamma#), S_t, P_t#right brace#. The CP violation is reflected in the polarisation asymmetry of the produced top quark. We use the angular distribution of the decay lepton from t/t-bar as a diagnostic of this polarisation asymmetry and hence of the CP mixing, after showing that the asymmetries in the angular distribution are independent of any CP violation in the tbW vertex. We construct combined asymmetries in the initial state lepton (photon) polarization and the final state lepton charge and study how well different combinations of these form ...

2003-09-01

230

An example of alkalization of SiO{sub 2} in a blast furnace coke  

Science.gov (United States)

Scanning electron microscopy and an electron-microprobe analysis of a sample of blast furnace (BF) coke have revealed alkalization (5.64 wt % Na{sub 2}O + K{sub 2}O) and Al saturation (17.28 wt % Al{sub 2}O{sub 3}) of SiO{sub 2} by BF gases. The K/Na{sub at} value of 1.15 in the new phase (alteration zone) reflects close atomic proportions of the elements and suggests that the abilities to incorporate K and Na during the process are almost equal. This Al saturation and alkalization of SiO{sub 2} indicates an active role for Al along with alkali metals in BF gases. The average width of the altered area in the SiO{sub 2} grain is about 10 m, which suggests that SiO{sub 2} particles of that size can be transformed fully to the new phase, provided that at least one of their faces is open to an external pore (surface of the coke) or internal pore with circulating BF gases. The grains that exceed 10 {mu}m can only be partly altered, which means that smaller SiO{sub 2} ...

2007-09-15

231

Aerodynamic effects of flexibility in flapping wings.  

Science.gov (United States)

Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re approximately 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic ...

2009-08-19

232

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

International Nuclear Information System (INIS)

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

2005-06-01

233

Tetracycline hydrochloride sclerotherapy; renal, hepatic, ovarian, and perivesical cysts  

Energy Technology Data Exchange (ETDEWEB)

To assess the efficacy and resulting complications of tetracycline sclerotherapy in renal, hepatic, ovarian, and perivesical cysts. We retrospectively reviewed 23 cases of benign cysts (16 renal, 4 hepatic, 2 ovarian, and 1 perivesical) in 22 patients in whom the condition was diagnosed or confirmed by either ultrasound, CT, or cytology, and who underwent percutaneous tetracycline sclerotherapy. Using a 21-gauge Chiba needle, the target cyst was punctured under ultrasound guidance. Prior to the injection of 1500 mg of tetracycline diluted in 5 ml of normal saline, almost all the cystic content was aspirated, and at the end of the procedure the tetracycline was left in the cyst. During a period of between 3 and 22 months, 18 of the 23 cases were followed up. In six of the 18 cases followed up, the cysts either decreased in size by 10%, or collapsed completely. In seven cases a collapse of over 50% was noted, and in the remaining five the cyst ...

2000-11-01

234

MRI-based N-staging in esophageal cancer  

International Nuclear Information System (INIS)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by two radiologists. ...

2002-10-01

235

Investigation of acoustic waves generated in an elastic solid by a pulsed ion beam and their application in a FIB based scanning ion acoustic microscope  

International Nuclear Information System (INIS)

The aim of this work is to investigate the acoustic wave generation by pulsed and periodically modulated ion beams in different solid materials depending on the beam parameters and to demonstrate the possibility to apply an intensity modulated focused ion beam (FIB) for acoustic emission and for nondestructive investigation of the internal structure of materials on a microscopic scale. The combination of a FIB and an ultrasound microscope in one device can provide the opportunity of nondestructive investigation, production and modification of micro- and nanostructures simultaneously. This work consists of the two main experimental parts. In the first part the process of elastic wave generation during the irradiation of metallic samples by a pulsed beam of energetic ions was investigated in an energy range from 1.5 to 10 MeV and pulse durations of 0.5-5 #mu#s, applying ions with different masses, e.g. oxygen, silicon and gold, in charge states from 1"+ to 4"+. The ...

236

Endobronchial ultrasound with transbronchial needle aspiration for restaging the mediastinum in lung cancer  

DEFF Research Database (Denmark)

Purpose To investigate the sensitivity and accuracy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for restaging the mediastinum after induction chemotherapy in patients with non-small-cell lung cancer (NSCLC). Patients and Methods One hundred twenty-four consecutive patients with tissue-proven stage IIIA-N2 disease who were treated with induction chemotherapy and who had undergone mediastinal restaging by EBUS-TBNA were reviewed. On the basis of computed tomography, 58 patients were classified as having stable disease and 66 were judged to have had a partial response. All patients subsequently underwent thoracotomy with attempted curative resection and a lymph node dissection regardless of EBUS-TBNA findings. Results Persistent nodal metastases were detected by using EBUS-TBNA in 89 patients (72%). Of the 35 patients in whom no metastases were assessed by EBUS-TBNA, 28 were found to have residual stage IIIA-N2 disease at ...

2008-01-01

237

Conservative treatment options for carpal tunnel syndrome: a systematic review of randomised controlled trials.  

Science.gov (United States)

Carpal tunnel syndrome (CTS) is a common disorder, for which various conservative treatment options are available. The objective of this study is to determine the efficacy of the various conservative treatment options for relieving the symptoms of CTS. Computer-aided searches of MEDLINE (1/1966 to 3/2000), EMBASE (1/1988 to 2/2000) and the Cochrane Controlled Trials Register (2000, issue 1) were conducted, together with reference checking. Included were randomised controlled trials evaluating the efficacy of conservative treatment options in a study population of CTS patients, with a full report published in English, German, French or Dutch. Two reviewers independently selected the studies. Fourteen randomised controlled trials were included in the review. Assessment of methodological quality and data-extraction was independently performed by two reviewers. A rating system, based on the number of studies and their methodological quality and findings, was used to determine the strength ...

2002-03-01

238

The waste problem - an inevitable consequence of energy consumption. Abfallproblematik - eine unabwendbare Folge des Energieeinsatzes  

Energy Technology Data Exchange (ETDEWEB)

'Within 15 years the energy consumption bottleneck has shifted from the supply side to emissions, i.e. to the waste side.' Reflecting this statement one may realize the importance of lending more weight to energy conservation but may also be induced to critically analyze the corresponding measures. First results of such reflections are given with regard to the payback periods of air pollution abatement measures relative to the additional emissions they cause. (orig.).

1991-12-18

239

Optic probe for semiconductor characterization  

Energy Technology Data Exchange (ETDEWEB)

Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

2008-09-02

240

Morphology of electrodeposited Ni/Cu multilayer: Specular and diffuse neutron reflectometry study  

Energy Technology Data Exchange (ETDEWEB)

Structural studies of Ni/Cu multilayers grown by electro-deposition technique under different electro-chemical conditions have been carried out using specular and off-specular neutron reflectometry techniques at room temperature. The specular reflectivity measurements give values of layer thickness, density and interface roughness for these two films. The Off-specular reflectivity measurements indicate different interface morphology of the two films.

2006-11-15

242

COMBUSTIBLE AMMUNITION FOR SMALL ARMS. 2. ...  

Science.gov (United States)

... Descriptors : *COMBUSTIBLE CARTRIDGE CASES, STYPHNATES, PHYSICAL PROPERTIES, TENSILE PROPERTIES, PRIMERS ...

1962-06-01

243

Experiment for deep seismic reflections in Hidaka, Hokkaido. Comparison between Vibroseis and explosive data; Hidaka chiiki ni okeru shinbu hanno data no shutoku jikken. Vibroseis to dynamite no hikaku  

Energy Technology Data Exchange (ETDEWEB)

This is a prompt report. These days the importance of acquiring knowledge about the structure from the lower crust down to the upper mantle is often discussed with reference taken to Hyogo-ken Nanbu Earthquake. The Hidaka collision belt where the lower crust is exposed on the surface is a rare phenomenon in the world and has been the subject of seismic survey. As a part of the survey, experiments are conducted by the use of vibrations produced by Vibroseis and dynamite sources. Every one of the shot records (20-second record) from the two types of vibration sources contains a clear echo in the vicinity of 16 seconds supposedly from a level deeper than 40 kilometers, not to mention reflections from shallow levels. Although some studies have to be conducted before the reflecting geological boundary (possibly the upper mantle) of the echo near the 16-second point can be identified, yet this is probably the reflection from the ...

1997-05-27

244

Concrete peeling off device  

Energy Technology Data Exchange (ETDEWEB)

The present invention concerns a device for peeling off activated concretes in processing for discarding a reactor of a nuclear reactor facility. The device comprises a gyrotron for generation microwaves, an irradiator for irradiating output microwaves, a reflection mirror for reflecting and converging the microwaves and irradiating them to a material to be irradiated and a first rotating means for rotating the irradiator and the reflection mirror in parallel with the axis of the gyrotron while maintaining the positional relation between the irradiator and the reflection mirror. When the position of the microwaves irradiated on concrete walls are moved in a circumferential direction and the central axes of the rotational axis and the material to be irradiated are aligned, then the intensity of the irradiation of the microwaves at each of the irradiation points can be maintained constant without changing ...

1997-11-28

245

Application of VSP to geological investigation; P ha oyobi S ha VSP wo mochiita shinso chishitsu chosa  

Energy Technology Data Exchange (ETDEWEB)

Discussed in this paper are the P-wave and S-wave zero-offset VSPs carried out utilizing boreholes located in Nada Ward, Kobe City, and Hokudan-cho, Hyogo Prefecture, as part of the deep layer boring survey following Hanshin Earthquake Disaster. This effort aims at the elucidation of P-wave and S-wave velocity structures, high-precision identification of data obtained by the surface reflection method, and collection of basic data for active faults investigation in the future. Among the velocity structures obtained for various layers, the S-wave velocity structures in particular agree with the stratigraphy excellently and may be utilized in seismic analyses to be conducted in the future. Reflection from geological boundaries is received with precision, providing accurate information about correlation between reflection and geological cross sections. The records will be useful in formulating plans for ...

1997-05-27

246

Synthesis, crystal structures and spectroscopic properties of RbBaTaS{sub 4} and K{sub 2}BaTa{sub 2}S{sub 11}  

Energy Technology Data Exchange (ETDEWEB)

Single crystals of RbBaTaS{sub 4} (1) and K{sub 2}BaTa{sub 2}S{sub 11} (2) were obtained from the reactions of Ta, with in situ formed fluxes of A{sub 2}S{sub 3} (A = K, Rb), BaS, and S at 500 C. Compound 1 crystallizes in the orthorhombic space group Pnma with a = 9.3286(5), b = 7.0391(4), c = 12.4365(7) A, V = 816.6(1) A{sup 3}, Z = 4. Compound 2 crystallizes in the monoclinic space group P2{sub 1}/c with a = 14.5280(10), b = 12.6347(7), c = 17.5148(12) A, {beta} = 94.744(8) , V = 3203.9(4) A{sup 3}, Z = 4. The structure of RbBaTaS{sub 4} (1) consists of isolated tetrahedral [TaS{sub 4}]{sup 3-} anions and Rb{sup +} and Ba{sup 2+} cations. The Ba{sup 2+} cations are surrounded by nine sulfur atoms forming distorted tricapped trigonal prisms, whereas the Rb{sup +} cations are in an irregular environment of ten sulfur atoms. The structure of K{sub 2}BaTa{sub 2}S{sub 11} (2) consists of two different dinuclear [Ta{sub 2}S{sub 11}] units which are separated by Ba{sup 2+} and K{sup +} ...

2010-10-15

247

Synthesis, crystal structure and optical properties of a novel sodium lead pentaborate, NaPbB5O9  

International Nuclear Information System (INIS)

A novel sodium lead pentaborate, NaPbB5O9, has been successfully synthesized by standard solid-state reaction. The single-crystal X-ray structural analysis showed that NaPbB5O9 crystallizes in the monoclinic space group P21/c with a=6.5324(10) A, b=13.0234(2) A, c=8.5838(10) A, ?=104.971(10)o, and Z=4. The crystal structure is composed of double ring [B5O9]3- units, [PbO7] and [NaO7] polyhedra. [B5O9]3- groups connect with each other forming two-dimensional infinite ?[B5O9]3- layers, while [PbO7] and [NaO7] polyhedra are located between the layers. [PbO7] polyhedra linked together via corner-sharing O atom forming novel infinite ?[PbO6] chains along the c axis. The thermal behavior, IR spectrum and the optical diffuse reflectance spectrum of NaPbB5O9 were reported. -- Graphical abstract: A new phase, NaPbB5O9, has been discovered in the ternary M2O-PbO-B2O3 (M=alkali-metal) system. The crystal structure consists of a novel infinite ?[PbO6] chains. Display Omitted ...

2011-04-01

248

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 used at various beam line locations so ...

1999-05-01

249

Perovskite-type SrTi1-xNbx(O,N)3 compounds: Synthesis, crystal structure and optical properties  

International Nuclear Information System (INIS)

The synthesis, crystal structure, thermal stability and absorbance spectra of perovskite-type oxynitrides with the general formula SrTi1-xNbx(O,N)3 (x=0.05, 0.10, 0.20, 0.50, 0.80, 0.90, 0.95) have been investigated. Oxide samples were prepared by a polymerized complex synthesis route and post-treated under ammonia at 850 oC for 24 h to substitute nitrogen for oxygen. Synchrotron X-ray powder diffraction (XRD) evidenced that the mixed oxide phases were all transformed into oxynitrides with perovskite-type structure during a thermal ammonolysis. SrTi1-xNbx(O,N)3 with compositions x?0.80 crystallized in a cubic and samples with x?0.90 in a tetragonal structure. The Rietveld refinement indicated a continuous enlargement of the lattice parameters towards higher niobium content of the samples. Thermogravimetric analysis (TGA) and hotgas extraction revealed the dependence of the nitrogen incorporation upon the degree of niobium substitution. It showed that more nitrogen was detected in the ...

2011-04-01

250

Electronic structure of face-centred cubic MoO_2: A comparative study by the full potential linearized augmented plane wave method, X-ray emission spectroscopy and X-ray photoelectron spectroscopy  

International Nuclear Information System (INIS)

X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) methods were employed in the present paper to investigate the electronic structure of face-centred cubic (fcc) molybdenum dioxide, fcc-MoO_2. For the mentioned compound, the XES O K#alpha# and Mo L#beta#_2_,_1_5 bands reflecting the valence O p- and Mo s,d-like states, respectively, were derived and compared on a common energy scale with the XPS valence-band spectrum. For comparison, the similar experimental studies of the electronic structure were made for a usual orthorhombic form of molybdenum trioxide, MoO_3. Band-structure calculations of fcc-MoO_2 were made using the full potential linearized augmented plane wave (FP-LAPW) method. A rather good agreement of the experimental XES and XPS results and the theoretical FP-LAPW data for the electronic properties of fcc-MoO_2 has been achieved in the present paper. A new near-Fermi sub-band was detected on both the XES ...

2008-07-14

251

Solar receiver-reactor with specularly reflecting walls for high-temperature thermoelectrochemical and thermochemical processes. Technical report  

Energy Technology Data Exchange (ETDEWEB)

A new kind of receiver-reactor for high-temperature solar furnaces is proposed. The main body of the receiver component is an ellipsoid of revolution with specularly reflecting inner walls. The reactor component, a crucible, is placed at one focal point and the aperture at the other. With this arrangement, substantially all of the incident radiation from the concentrator should reach the reactor directly or after one reflection from the cavity walls. An analysis of the radiative exchange among the surfaces is presented. The analysis provides a tool for a parametric study and optimization of the design. It is found that, in contrast to that of conventional well-insulated cavity receivers, its collection efficiency is not very sensitive to the size of its aperture.

1987-10-27

252

Solar cell  

Energy Technology Data Exchange (ETDEWEB)

For a solar cell, in order to minimize the loss of incident light, transparent glass or plastic material is used at the incident part. When a solar cell is watched from the light incident part, a silicon base material is directly observed with either block or brown color only. This invention enables a solar cell to give brighter color on the incident surface by placing a reflective film which reflects only the light of specific wavelength, without reducing the efficiency of the solar cell. This reflective film consists of multi-layered dielectric with 12 layers and alternative combination of highly refractive and less refractive substances. Highly refractive layer is Y/sub 2/O/sub 3/ with refractive index 1.74 and the less refractive layer is SiO/sub 2/ with refractive index 1.45. (5 figs)

1987-09-19

253

Isomorphisms of quantizations via quantization of resolutions  

CERN Document Server

In this paper we prove the existence of isomorphisms between certain non-commutative algebras that are interesting from representation theoretic perspective and arise as quantizations of certain Poisson algebras. We show that quantizations of Kleinian resolutions obtained by three different constructions are isomorphic to each other. The constructions are via symplectic reflection algebras, quantum Hamiltonian reduction, and W-algebras. Next, we prove that parabolic W-algebras in type A are isomorphic to quantum Hamiltonian reductions associated to quivers of type A. Finally, we show that the symplectic reflection algebras for wreath-products of the symmetric group and a Kleinian group are isomorphic to certain quantum Hamiltonian reductions. Our results involving W-algebras are new, while for those dealing with symplectic reflection algebras we just give new proofs. A key ingredient in our proofs is the study of ...

2010-01-01

254

Enhanced reflectance mirrors for space-borne HF laser applications  

Science.gov (United States)

Combined electron, photon, and intense UV irradiation tests have been carried out on three mirror designs, (Si, Al/sub 2/O/sub 3/)/sub 2/Ag, (Si, SiOx)nAg, and (ZnS, Al/sub 2/O/sub 3/)4Ag, to investigate their suitability for space-borne chemical laser applications. It is found that the (Si, oxide)nAg enhanced-reflectance design is a viable candidate for such applications, whereas ZnS, in combination with either ThF/sub 4/ or Al/sub 2/O/sub 3/, shows unacceptably high absorption increases at the 2.8-micron HF laser wavelength with irradiation. It is pointed out, however, that further experiments are needed to fully understand the effect of irradiation on the (Si, oxide)nAg enhanced-reflectance mirrors.

1981-01-01

255

Broad-band hard X-ray reflectors  

DEFF Research Database (Denmark)

Interest in optics for hard X-ray broad-band application is growing. In this paper, we compare the hard X-ray (20-100 keV) reflectivity obtained with an energy-dispersive reflectometer, of a standard commercial gold thin-film with that of a 600 bilayer W/Si X-ray supermirror. The reflectivity of the multilayer is found to agree extraordinarily well with theory (assuming an interface roughness of 4.5 Angstrom), while the agreement for the gold film is less, The overall performance of the supermirror is superior to that of gold, extending the band of reflection at least a factor of 2.8 beyond that of the gold, Various other design options are discussed, and we conclude that continued interest in the X-ray supermirror for broad-band hard X-ray applications is warranted.

1997-01-01

256

Andreev reflection spectroscopy of MgB{sub 2} in the vortex state  

Energy Technology Data Exchange (ETDEWEB)

Spectroscopy based on the Andreev reflection (AR) process at the interface between the normal metal tip and the superconductor has become one of the very successful methods for studies in novel exotic superconductors. The method is capable to address the size, symmetry as well as multiplicity of the superconducting order parameter. The method provided one of the first evidences of the two-gap superconductivity in MgB{sub 2} with a detailed temperature dependence of the both gaps. A theory treating the Andreev reflection spectroscopy in the mixed state is missing. We analyse the AR spectra of MgB{sub 2} in the mixed state via modelling the magnetic pair-breaking by the increasing spectral broadening parameter {gamma}. As a result a non-trivial pair breaking effect in the {pi}-band is found.

2004-05-01

257

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 ...

1994-05-01

258

Phase of space of tachyons  

Energy Technology Data Exchange (ETDEWEB)

The aim of this paper is to present the phase-space properties of the systems that contain bradyons, luxons and tachyons. It is shown that particularly at low energy, these properties are quite different from the well-known properties of bradyons.

1983-03-12

259

[Natural course of asymptomatic gallstone disease].  

Science.gov (United States)

Of 1850 patients with cholelithiasis diagnosed in the past 17 years, 1116 female and 734 male, 598 patients (32.3%) presented with one or more of three major symptoms, i.e., abdominal pain, fever and jaundice, whereas the remainder (67.7%) had none of these symptoms. The proportion of the asymptomatic patients was similar in all age groups, being around 70%. Only 20 per cent of 680 asymptomatic patients, followed for 10 to 17 years (median 13.3 years), developed biliary symptoms. Older patients over 70 years of age had a higher rate of change to the symptomatic group, as compared with younger patients under 70, 29.5% vs. 19.3%, respectively. During this period, carcinoma of the gallbladder developed in one of the asymptomatic patients (0.1%). Oral dissolution therapy was successful in only 4.2 per cent of attempted cases and associated with a recurrence rate of as high as 20%. We conclude that asymptomatic gallstone patients should only be followed up by ultrasound ...

1993-07-01

260

The safety issues of medical robotics  

International Nuclear Information System (INIS)

In this paper, we put forward a systematic method to analyze, control and evaluate the safety issues of medical robotics. We created a safety model that consists of three axes to analyze safety factors. Software and hardware are the two material axes. The third axis is the policy that controls all phases of design, production, testing and application of the robot system. The policy was defined as hazard identification and safety insurance control (HISIC) that includes seven principles: definitions and requirements, hazard identification, safety insurance control, safety critical limits, monitoring and control, verification and validation, system log and documentation. HISIC was implemented in the development of a robot for urological applications that was known as URObot. The URObot is a universal robot with different modules adaptable for 3D ultrasound image-guided interstitial laser coagulation, radiation seed implantation, laser resection, and electrical ...

2001-08-01

261

Solid-pseudopapillary tumor of the pancreas in a 13-year-old girl - case report  

International Nuclear Information System (INIS)

The solid-pseudopapillary tumor (SPT) of the pancreas is a rare type of exocrine pancreatic neoplasm. SPT predominantly affects young women and female children, and is usually discovered incidentally. This tumor is generally benign with a low incidence of malignancy. A 13-year-old girl was admitted to the hospital with a few weeks' history of mild abdominal pain and jaundice. On physical examination, there was no palpable mass. The laboratory tests showed increased SR, CRP, high bilirubin, amylase and lipase serum levels. Ultrasound imaging revealed a solid lesion in the region of the pancreatic head. On MRI, precise tumor localization in the head of the pancreas with pancreatic duct dilatation and compression of the common bile duct were visualized. Pancreaticoduodenectomy and cholecystectomy was performed with good clinical outcome. Microscopic and immunohistochemical studies indicated that tumor cells were typical of SPT without any signs of malignancy. After ...

262

Percutaneous drainage of abdominal abcess  

Energy Technology Data Exchange (ETDEWEB)

The mortality in undrained abdominal abscesses is high with a mortality rate ranging between 45 and 100%. The outcome in abdominal abscesses, however, has improved due to advances in image guided percutaneous interventional techniques. The main indications for the catheter drainage include treatment or palliation of sepsis associated with an infected fluid collection, and alleviation of the symptoms that may be caused by fluid collections by virtue of their size, like pancreatic pseudocele or lymphocele. The single liver abscesses may be drained with ultrasound guidance only, whereas the multiple abscesses usually require computed tomography (CT) guidance and placement of multiple catheters. The pancreatic abscesses are generally drained routinely and urgently. Non-infected pancreatic pseudocysts may be simply observed unless they are symptomatic or cause problems such as pain or obstruction of the biliary or the gastrointestinal tract. Percutaneous routes that ...

2002-09-01

263

Opto-acoustic recanilization delivery system  

Energy Technology Data Exchange (ETDEWEB)

Fiber delivered laser pulses emulsify thrombus by mechanical stresses that include a combination of pressure, tension and shear stress. Laser radiation is delivered to the locality of a thrombus and the radiation is absorbed by blood, blood dot, or other present materials. The combination of a leading pressure wave and subsequent vapor bubble cause efficient, emulsification of thrombus. Operating the laser in a low average power mode alleviates potential thermal complications. The laser is operated in a high repetition rate mode to take advantage of ultrasound frequency effects of thrombus dissolution as well as to decrease the total procedure time. Specific parameter ranges for operation are described. The device includes optical fibers surrounding a lumen intended for flow of a cooling agent. The fibers may be arranged concentrically around the lumen to deliver radiation and heat over as large an area as possible. An alternative design approach incorporates the ...

2002-01-01

264

Is intraoperative ultrasound (IOUS) still useful for the detection of liver metastases?  

British Library Electronic Table of Contents (United Kingdom)

SommarioScopo Valutare limpatto clinico negli anni dellecografia intraoperatoria (IOUS) nella identificazione delle metastasi epatiche rispetto alle altre metodiche di imaging. Materiali e metodi risultati delle ecografie intraoperatorie effettuate per lidentificazione delle metastasi epatiche in un periodo compreso tra gli anni 2000 e 2006 sono stati retrospettivamente revisionati e comparati con le metodiche di imaging preoperatorio: Ecografia (US), Tomografia Computerizzata (TC) e/o Risonanza Magnetica (RM). Tutti i casi sono stati patologicamente provati. Sono stati calcolati per anno i casi discordanti in termini di presenza/assenza di lesione focale epatica. Il confronto statistico e stato effettuato con il test di McNemar. Un valore del p<0,05 e stato considerato statisticamente sig...

2009-01-01

265

Diagnostic imaging and interventional radiology of the amoebic liver abscess. Personal experience; Diagnostica per immagini e radiologia interventistica degli ascessi amebici del fegato: esperienza personale  

Energy Technology Data Exchange (ETDEWEB)

The diagnostic imaging findings in hepatic amoebiasis and the capabilities of percutaneous drainage have already been described but some debate is open on both diagnosis and treatment. It is reported the experience with the ultrasound (US) and Computed Tomography (CT) studies of the hepatic amoebic abscess and its management. [Italian] I reperti con diagnostica per immagini nell'amebiasi epatica e le possibilita' del drenaggio percutaneo sono stati gia' illustrati; esistono tuttavia controversie sul piano sia diagnostico che terapeutico. Obiettivo di questo lavoro e' quello di riportare l'esperienza personale nella diagnostica con ecografia e tomografia computerizzata (TC) e nel trattamento degli ascessi amebici del fegato.

1999-10-01

266

Assessment of flow quantification in coronary bypass grafts and coronary arteries with velocity-encoded cine MR imaging; Flussquantifizierung in Koronar- und Bypassgefaessen mit der MR-Phasenkontrasttechnik  

Energy Technology Data Exchange (ETDEWEB)

Materials and methods: 12 patients with 22 coronary bypass grafts underwent intraoperative flow quantification using the transit time ultrasound method. These values were compared to postoperative MR phase shift measurements. Flow measurements were performed preoperatively in 28 coronary arteries of 20 patients. For flow measurement, we used a velocity-encoded k-space segmented gradient echo sequence with a temporal resolution of 110 or 125 ms, respectively. 6-8 pase shift images could be acquired during one cardiac cycle. Results: There was a significant correlation between intraoperative and flow measurements using velocity-encoded MR imaging (r=0.76, p<0.0001, t-test). Flow volumes determined by MR imaging were systematically larger than those determined by the transit time ultrasound method. Mean flow in coronary arteries was reduced in severely stenosed vessels (>70%) compared to normal vessels. Intra- and interobserver ...

2000-02-01

267

Wafer and Solar Cell Characterization by GT-PVSCAN6000  

Science.gov (United States)

The PVSCAN is an instrument designed to characterize silicon solar cell materials and devices. It performs a host of measurements that yield spatial maps of dislocation density, grain distribution, reflectance, and photoresponses from near-junction and the bulk of a solar cell.

2002-08-01

268

Understanding Enzyme Activity Using Single Molecule Tracking (Poster)  

Energy Technology Data Exchange (ETDEWEB)

This poster describes single-molecule tracking and total internal reflection fluorescence microscopy. It discusses whether the carbohydrate-binding module (CBM) moves on cellulose, how the CBM binds to cellulose, and the mechanism of cellulosome assembly.

2009-06-01

269

Tau Boo b: Hunting for reflected starlight  

CERN Document Server

Aims. We attempt to detect starlight reflected from the hot Jupiter orbiting the main-sequence star Tau Boo, in order to determine the albedo of the planetary atmosphere, the orbital inclination of the planetary system and the exact mass of the planetary companion. Methods. We analyze high-precision, high-resolution spectra, collected over two half nights using UVES at the VLT/UT2, by way of data synthesis. We interpret our data using two different atmospheric models for hot Jupiters. Results. Although a weak candidate signal appears near the most probable radial velocity amplitude, its statistical significance is insufficient for us to claim a detection. However, this feature agrees very well with a completely independently obtained result by another research group, which searched for reflected light from Tau Boo b. As a consequence of the non-detection of reflected light, we place upper limits to the planet-to-star flux ...

2010-01-01

270

Spectroscopic ellipsometry and polarimetry for materials and systems analysis at the nanometer scale: state-of-the-art, potential, and perspectives  

UK PubMed Central (United Kingdom)

This paper discusses the fundamentals, applications, potential, limitations, and future perspectives of polarized light reflection techniques for the characterization of materials and related systems...Full Text Available

2009-10-01

271

Reverse time migration for ground penetrating radar using finite difference time domain method; Jikan ryoiki yugenn sabunho ni yoru chichu reda no ribasu taimu maigureshon  

Energy Technology Data Exchange (ETDEWEB)

The reversion time migration, as one of reflection seismic prospecting migration, reverse propagates a wave equation by reverse promoting the differential time, and conducts the migration. The method has such merits as no limit to the inclined angle of a reflection, correspondence to a complex topography etc. And, there is a finite difference time domain (FDTD) that uses the Maxwell equation as it is and makes a difference approximation in the methods differentiating and resolving electro-magnetic fields. It is also possible to apply the reverse time migration onto it. In this speech, using an explosive reflection face, a slope 2 layer structure and models of its reflection points are synthesized by a ground penetrating radar using the FDTD, and reverse time migration is conducted. As a result, it is clarified that the reverse time migration is valid for the ground penetrating radar recording. And, the ...

1999-02-01

272

Receptive Field Remodeling Induced by Skin Stimulation in Cerebellar Neurons in vivo  

UK PubMed Central (United Kingdom)

The receptive field of a neuron reflects its function. For example, for parallel fiber (PF) inputs in C3 zone the cerebellar cortex, the excitatory and inhibitory receptive fields of a Purkinje cell...Full Text Available

273

Quantification of physical and biological uncertainty in the simulation of the yield of a tropical crop using present-day and doubled CO2 climates  

UK PubMed Central (United Kingdom)

The impacts of climate change on crop productivity are often assessed using simulations from a numerical climate model as an input to a crop simulation model. The precision of these predictions reflects...Full Text Available

2005-11-29

274

Prototype Web-based continuing medical education using FlashPix images.  

UK PubMed Central (United Kingdom)

Continuing Medical Education (CME) is a requirement among practicing physicians to promote continuous enhancement of clinical knowledge to reflect new developments in medical care. Previous research...Full Text Available

2000-01-01

275

Prospective Memory in HIV-1 Infection  

UK PubMed Central (United Kingdom)

The cognitive deficits associated with HIV-1 infection are thought to primarily reflect neuropathophysiology within the fronto-striato-thalamo-cortical circuits. Prospective memory (ProM) is...Full Text Available

2006-05-01

276

Probing the Geometry and Physics of the Emission Region in Active Galactic Nuclei using hard X-ray & Gamma-ray Observations  

Energy Technology Data Exchange (ETDEWEB)

The X-ray spectra of {approx}200 AGN collected from Swift-BAT were analyzed to test the Unified Model for AGN. Specifically, the photon indices, high energy cutoffs, and reflection components of Sy1 and Sy2 were compared. Under the Unified Model, the photon indices and reflection components for Sy1 should be larger than Sy2 and the high energy cutoffs should be the same. Fitting a simple power law model to the sample spectra proved to be insufficient. The PEXRAV model fit the spectra of the Sy1 and Sy2 significantly better, indicating that a reflection component and/or high energy cutoff exists as the Unified Model expects. Using both the simple power law and PEXRAV models it was concluded that in the population studied, Sy1 had a larger photon index than Sy2, as expected by the Unified Model. For Sy1 and Sy2, the reflection components were found to be compatible, but given the large errors, this ...

2010-08-25

277

Oral Health in Women During Preconception and Pregnancy: Implications for Birth Outcomes and Infant Oral Health  

UK PubMed Central (United Kingdom)

The mouth is an obvious portal of entry to the body, and oral health reflects and influences general health and well being. Maternal oral health has significant implications for birth outcomes and infant...Full Text Available

2006-09-01

278

Numerical simulations of quantized Bianchi type IX cosmological models  

International Nuclear Information System (INIS)

This paper reports on Monte Carlo path integral simulations of a Bianchi Type IX cosmology which yield a wave function which reflects the known chaotic dynamics of the classical system and predicts a significant probability for a correlation between large universe volume and large anisotropy.

1988-08-08

279

NASA Surfs the Skies Above Oahu, Hawaii  

National Aeronautics and Space Administration (NASA)

This flyover of the Hawaiian island of Oahu was made by draping Jan. 13, 2010, image data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft over new ASTER Version 2 digital elevation data.

2011-10-17

280

Longitudinal Evaluation of Sexual Function in a Male Cohort: The Olmsted County Study of Urinary Symptoms and Health Status among Men  

UK PubMed Central (United Kingdom)

IntroductionThe presence of erectile or ejaculatory dysfunction may indicate physical problems; however, individual perceptions (e.g., sexual satisfaction) may reflect...Full Text Available

2009-09-01

281

Life after Breast Cancer: Dealing with Lymphoedema  

UK PubMed Central (United Kingdom)

Background:In recent years, breast cancer (BC) mortality rates have declined, reflecting advances in early detection. Prevention and management of treatment sequelae that could impair...Full Text Available

282

Interictal Functional Connectivity of Human Epileptic Networks Assessed by Intracerebral EEG and BOLD Signal Fluctuations  

UK PubMed Central (United Kingdom)

In this study, we aimed to demonstrate whether spontaneous fluctuations in the blood oxygen level dependent (BOLD) signal derived from resting state functional magnetic resonance imaging (fMRI) reflect...Full Text Available

283

Information Sharing in the Era of WikiLeaks: Balancing Security and Collaboration.  

Science.gov (United States)

As the IC Information Sharing Executive (IC ISE), my main focus today concerns classified information--and, in particular, information that is derived from intelligence sources and methods, or information that is reflected in the analytic judgments and as...

2011-01-01

284

Increased wind-up to heat pain in women with a childhood history of functional abdominal pain  

UK PubMed Central (United Kingdom)

Idiopathic or functional abdominal pain (FAP) is common in school-age children and typically reflects a functional gastrointestinal disorder (FGID). FGIDs in adults have been distinguished by...Full Text Available

2011-04-01

285

Improving yield of industrial biomass propagation by increasing the Trx2p dosage  

UK PubMed Central (United Kingdom)

The beneficial effect of improving yeast redox response by increasing thioredoxin levels has been shown. Decreased lipid and protein oxidation is reflected in an increased biomass yield. In addition,...Full Text Available

2010-09-01

286

How representative was the 1996 VOTALP Mesolcina Valley campaign?  

Energy Technology Data Exchange (ETDEWEB)

Each meteorological measurement reflects the conditions under which it was obtained, e.g. site, weather, and instrumentation. It is shown how the VOTALP Intensive Observation Periods (IOPs) were embedded in the climatic context of the summer months of 1996. (author) 1 fig., 2 refs.

1999-08-01

287

High Contrast Near-infrared Polarized Reflectance Images of Demineralization on Tooth Buccal and Occlusal Surfaces at ?=1310-nm  

UK PubMed Central (United Kingdom)

Background and Objectives:Sound enamel manifests peak transparency in the near-IR (NIR) at 1310-nm, therefore the near-IR is ideally suited for high contrast imaging...Full Text Available

2009-03-01

288

HD 75289Ab revisited - Searching for starlight reflected from a hot Jupiter  

CERN Document Server

Aims. We attempt to detect starlight reflected from a hot Jupiter, orbiting the main-sequence star HD 75289Ab. We report a revised analysis of observations of this planetary system presented previously by another research group. Methods. We analyse high-precision, high-resolution spectra, collected over four nights using UVES at the VLT/UT2, by way of data synthesis. We try to interpret our data using different atmospheric models for hot Jupiters. Results. We do not find any evidence for reflected light, and, therefore, establish revised upper limits to the planet-to-star flux ratio at the 99.9% significance level. At high orbital inclinations, where the best sensitivity is attained, we can limit the relative reflected radiation to be less than e = 6.7 x 10-5 assuming a grey albedo, and e = 8.3 x 10-5 assuming an Class IV function, respectively. This implies a geometric albedo smaller than p = 0.46 and p = 0.57, for the ...

2008-01-01

289

Glycolipids of human primary testicular germ cell tumours.  

UK PubMed Central (United Kingdom)

The glycolipid content of human non-seminomatous germ cell tumour cell lines correlates with their differentiation lineage. To analyse whether this reflects the situation in primary tumours, we studied...Full Text Available

1996-07-01

290

Gene-Environment Interactions in Schizophrenia: Review of Epidemiological Findings and Future Directions  

UK PubMed Central (United Kingdom)

Concern is building about high rates of schizophrenia in large cities, and among immigrants, cannabis users, and traumatized individuals, some of which likely reflects the causal influence of environmental...Full Text Available

2008-11-01

291

From Rapid Place Learning to Behavioral Performance: A Key Role for the Intermediate Hippocampus  

UK PubMed Central (United Kingdom)

Rapid place encoding by hippocampal neurons, as reflected by place-related firing, has been intensely studied, whereas the substrates that translate hippocampal place codes into behavior have received...Full Text Available

2009-04-01

292

Final report for the Pre-Freshman Enrichment Program (PREP)  

Energy Technology Data Exchange (ETDEWEB)

This project reflected cooperation across the disciplines in the physical sciences, engineering, mathematics and computer science. The University of the Pacific served as the center for this pre-college program. The idea was to use this link as a pilot program.

1998-03-01

293

Estimating a preference-based index for a menopause specific health quality of life questionnaire  

UK PubMed Central (United Kingdom)

BackgroundThe aim of the study was to develop a menopause-specific, preference-based health-related quality-of-life (HRQoL) index reflecting both menopausal symptoms and potential...Full Text Available

294

Editorial: EEG Phenomenology and Multiple Faces of Short-term EEG Spectral Pattern  

UK PubMed Central (United Kingdom)

An electroencephalogram (EEG) signal is extremely nonstationary, highly composite and very complex, all of which reflects the underlying integral neurodynamics. Understanding the EEG “grammar”,...Full Text Available

295

Computer simulation of protein self-association during small-zone gel filtration. Estimation of equilibrium constants.  

UK PubMed Central (United Kingdom)

A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available

1981-04-01

296

Cognitive Expertise, Emotional Development and Reflective Capacity: Clinical Skills for Improved Pain Care  

UK PubMed Central (United Kingdom)

The overarching goal of medical training is to nurture the growth of knowledgeable, caring and insightful clinicians guided by the ideals of medical professionalism. Recent definitions of professional...Full Text Available

2008-11-01

297

Characterizing and estimating rice brown spot disease severity using stepwise regression, principal component regression and partial least-square regression*  

UK PubMed Central (United Kingdom)

Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa...Full Text Available

2007-10-01

298

Calcium Effects on Stomatal Movement in Commelina communis L. 1  

UK PubMed Central (United Kingdom)

Stomatal movements depend on both ion influx and efflux; attainment of steady state apertures reflects modulation of either or both processes. The role of Ca2+ in those two processes was...Full Text Available

1988-07-01

299

Automated 3-D method for the correction of axial artifacts in spectral-domain optical coherence tomography images  

UK PubMed Central (United Kingdom)

The 3-D spectral-domain optical coherence tomography (SD-OCT) images of the retina often do not reflect the true shape of the retina and are distorted differently along the x and y...Full Text Available

300

Annual Report for Gravity Collection Lysimeter Monitoring Plan - ERDF Cells 5 and 6  

Energy Technology Data Exchange (ETDEWEB)

The data and analyses contained in this report reflect the initial characterization of construction and consolidation water in Cells 5 and 6 lysimeters. Therefore, the scope of this report will be to establish constituent levels and document dewatering activities completed to date.

2006-12-19

301

A radiator of electromagnetic waves with a combined shape of generatrices  

British Library Electronic Table of Contents (United Kingdom)

The problem of optimizing a horn radiator of electromagnetic waves for the reflection coefficient and the coefficient of transformation of the fundamental mode into higher order modes is solved. Optimization is performed by means of selecting a combined shape of the radiator generatrices.

2008-01-01

302

5 - NASA Technical Reports Server  

Science.gov (United States)

The mission includes a reflected solar instrument retrieving at-sensor .... incoming solar radiation. This direct aerosol radiative forcing (DARF) ... examining the behavior of geosynchronous rocket bodies and non-stabilized payloads as ...

303

Using PCAR to study Cu/Co bilayers  

International Nuclear Information System (INIS)

For spintronic applications it is important to establish how efficiently spins can be injected from a magnetic material into a non-magnetic material and the distance over which those spins survive. It is thought that spin polarised transport current can be determined by using the suppression of the Andreev reflection between a superconductor and the spin polarised material (Science 282 (1998) 85). Cu/Co bilayers are potentially an ideal test system for such study. In this paper we assess the feasibility of using point contact Andreev reflection spectroscopy to address this problem using a superconducting niobium tip at 4.2 K.

2004-05-01

304

Use of real-time Fourier Transform Infrared Reflectivity as an in situ monitor of YBCO film growth and processing  

CERN Document Server

Fourier Transform Infrared (FTIR) spectroscopy has been utilized during high rate E-beam evaporation/deposition of YBa2Cu3O7 (YBCO). The results demonstrate the great utility of FTIR as an in situ monitor of YBCO deposition and processing. We detect different (amorphous/fine polycrystalline) insulating pre-existing phases to the high Tc superconducting phase which appear to have distinct reflectivity fingerprints dominated by thin film interference effects, as a function of temperature and oxygen pressure. These fingerprints reveal some of the kinetic and thermodynamic pathways during the growth of YBCO.

2007-01-01

305

Infrared spectroscopy analysis of MgO-doped silicon nitride  

Energy Technology Data Exchange (ETDEWEB)

Silicon nitride hybrid ball bearings used in high temperature applications undergo mechanical and environmental degradation. To study the surface chemistry of silicon nitride, a CAChe{trademark} Worksystem* has been used to generate the clusters and corresponding transmission vibrational spectra of silicon nitride. In the present study, the effect of surface conditions on the surface chemistry and wear degradation of silicon nitride was evaluated. Infrared reflection spectroscopy (IRRS) used to determine molecular orientations shows a difference in reflectance spectra for fractured and as-received.

1997-12-31

306

Fear, panic and prosperity consciousness: developing resilience as the paradigm shifts  

British Library Electronic Table of Contents (United Kingdom)

Purpose - The article shares insights from a program that was developed to address burnout, compassion fatigue and vicarious trauma. The program works from the premise that people and organizations thrive when they have shared values and common understandings. Design/methodology/approach - The approach draws together reflection at the organizational and person levels. Connecting business ethics and organizational analysis, improving understanding of the body's energy as well as inter-cultural understanding are all achievable while adopting the resilience development methods. Findings - The article concludes that reflective practice through the tools used on the program enhances understanding of the challenges faced by organizations and the individuals involved. It provides creative routes ...

2009-01-01

307

Educational research in Confucian cultural contexts: reflections on methodology  

British Library Electronic Table of Contents (United Kingdom)

This paper engages in a critical discussion of the key features delineated by the other authors in this Special Issue thus serving as an end-piece for the issue. In particular it touches on three significant concepts. Firstly, it reinforces the importance of context, particularly cultural context in the conduct of research in Confucian cultural settings. Second, as an illustration, it offers a critical perspective on the cultural assumptions that underpin the development of Chinese higher education. Finally, it concludes with some reflections on how other papers in this Special Issue contribute to our understanding of research in CHC contexts.

2011-01-01

308

Application of light microscopy to direct coal liquefaction research  

Energy Technology Data Exchange (ETDEWEB)

Light microscopy was used to analyze the effects of added catalyst at different conditions (temperature and reaction times) in liquefaction testing of a low pyritic sulfur bituminous coal. Quantitative changes in vitrinite/vitroplast reflectance of coal and liquefaction residues were shown to be useful markers in analyzing and understanding the role of catalyst during the initial stage of coal particle hydrogenation. Lower reflectance values corresponded to increased conversions up to about the 60 min and 375{degrees}C experimental conditions. Microscopical observation of liquefaction residues also revealed the presence of `wall scales` of varying width.

1998-01-01

324

EFFECTS OF SHIELDING ON PROPERTIES OF EDDY ...  

Science.gov (United States)

... Accession Number : ADD323869. Title : EFFECTS OF SHIELDING ON PROPERTIES OF EDDY CURRENT PROBES WITH FERRITE CUP CORES. ...

1986-08-01

325

Characteristics of the Mechanical Properties and the Fractures ...  

Science.gov (United States)

... Accession Number : ADA136144. Title : Characteristics of the Mechanical Properties and the Fractures of an Alpha Beta Titanium Alloy,. ...

1983-11-18

326

A Deflationary Metaphysics of Morality  

British Library Electronic Table of Contents (United Kingdom)

The metaphysical dispute between moral realists and antirealists is cast in terms of properties: the realist holds that moral properties exist, the antirealist denies this claim. There is a longstanding philosophical dispute over the nature of properties, and the obscurity of properties may make the realist/antirealist dispute even more obscure. In the spirit of deflationary theories of truth, we can turn to a deflationary theory of properties in order to clarify this issue. One might reasonably worry that such an account of properties would not be capable of properly characterizing disputes regarding the existence or nonexistence of genuine moral properties. In this paper, I will show that, within this framework, the traditional disputes over the existence of moral properties can be chara...

2010-01-01

327

Inhomogeneity of mechanical and fatigue properties of Al-Li alloys extrusions  

Energy Technology Data Exchange (ETDEWEB)

Aluminium-lithium extrusions possess high inhomogeneity of properties across the cross section. Mechanical properties such as R{sub p0,2}, R{sub m} and hardness, but also fatigue properties, change their value in dependence with the cross section position where test specimens were taken. Positions, where extreme values of properties are measured, are characteristic for a given extrusion shape. The positions with different properties have different structure and texture. Properties and structure inhomogeneity is affected mainly by extrusion shape and heat treatment parameters. (orig.)

1996-12-01

328

Investigations on solar grade silicon and process engineering of advanced silicon solar cells  

Energy Technology Data Exchange (ETDEWEB)

This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference cell suggests the formation of a B-metal complex in the SoG-Si ...

2007-07-01

329

Water uptake and exchange kinetics of polyelectrolyte films: a neutron reflectometry study  

Energy Technology Data Exchange (ETDEWEB)

The sequential layer-by-layer adsorption of polyanions and polycations to build polyelectrolyte multilayers has triggered enormous interest in their potential uses in a wide range of fields, from photonic to pharmaceutical applications. We show that the conformation of the solvent swollen films - prior to drying - is determined by the initial adsorption conditions, but can be altered ex-situ by exposure to a liquid phase of very high ionic strength. Recently it has been observed that the swelling depends on the charge of the outermost layer. In the PAH/PSS system we saw that assemblies with PSS as the outermost layer swell more than those with PAH outside. A neutron reflectivity study of this effect in addition indicated the existence of two kinds of water, bound with different strength within the films. Beside an unexpected two-step kinetics of swelling, the reflectivity curves of the layers against vacuum before and after re-hydration in ...

2007-07-01

330

Ultrafast carrier dynamics of InGaAsN and InGaAs single quantum wells  

International Nuclear Information System (INIS)

Striking differences in differential reflectance and carrier relaxation in In0.4Ga0.6As and In0.4Ga0.6As0.98N0.02 single quantum wells (SQWs) were studied using ultrafast time-resolved photoreflectance. Even with extremely thin SQW of only 60 A within 3000 A wide GaAs confining layers, negative and positive differential reflectance was observed for the excitation photon energy far above the bandgaps at 820 and 880 nm for both samples. Due to absorption by the GaAs confining layer, the peak differential reflectance pumped at 820 nm is an order of magnitude larger than that pumped at 880 nm; and it is larger for InGaAs SQWs than for InGaAsN SQWs. The shorter carrier lifetimes of these samples result from carrier-carrier scattering as pumped at both wavelengths. The longer carrier lifetime as pumped at 880 nm is due to hot phonon decay in InGaAs but may be due to stimulated emission in InGaAsN. The results reveal that the ...

2008-04-21

331

Time contour expression of limited range phenomena on stack chart; Jugo chart jo deno kyokuchi gensho jikan contour  

Energy Technology Data Exchange (ETDEWEB)

Time contour expression of limited range phenomena on stack chart is examined for further improvement on the result of the ultimate interpretation in the seismic reflection survey. The policy is made clear from the beginning that local phenomena are to be discussed, and data prior CMP stacking is interpreted in detail. For this purpose, it is effective to make use of the time contour expression in the midpoint-offset plane simultaneously with the CMP and COP panels. For the review of data prior to CMP stacking, it is convenient to use the CMP (CDP) stacking chart in which the data is arranged methodically. In this chart, all the channels which are crude data prior to stacking are plotted on midpoint-offset coordinates, which plane is called the MOD (Midpoint Offset Domain) panel. Various panels can be chosen unrestrictedly, and their mutual relations can be easily grasped. When data points are given a time axis, they can be expressed in a time contour. Studies are ...

1997-05-27

332

Thermal infrared spectra of surface rocks. Comparison of in the laboratory, in situ, and remote sensing data; Chihyo ganseki no netsusekigaiiki bunko tokusei. Chijo sokutei data to remote sensing data no hikaku  

Energy Technology Data Exchange (ETDEWEB)

An ASTER (advanced spaceborne thermal emission and reflection radiometer) is one of the image sensors. It is to be installed in an earth survey polar orbit platform satellite, EOS-AM1, which is to be launched in 1998, and it is going to start its operation. Data observed by the thermal infrared remote sensing of ASTER include the spectral emissivity, and the spectral emission reflectivity which is expressed by the function of temperature. It is required to overcome technical problems how to extract the spectral emissivity from the observed data. The spectral emissivity extracted from the remote sensing data by the MMD method, measured for samples collected in Cuprite area, Nevada, and/or measured at sampled points were compared to each other and discussed. The hemisphere spectral reflectivity, which is indirect spectral emissivity, agreed well with the direct spectral emissivity. Data suggesting the establishment of ...

1996-10-01

333

Surface physics with cold and thermal neutron reflectometry. Progress report, April 1, 1991--March 31, 1992  

Energy Technology Data Exchange (ETDEWEB)

Three aspects of the research project ``Surface physics with cold and ultracold neutron reflectometry`` were stressed during the present first year: (1) Setup of the reflectometer facility at the research reactor of the Rhode Island Nuclear Science Center. The installation provides a narrow ``pencil beam`` analyzed by time of flight using a chopper system. Following beam characterization and a test measurement of the total cross section of copper single crystal first reflectivity measurements are currently performed using a supermirror. (2) Design stud for the ultracold neutron imaging system, with involvement of the relevant industry. Bids are available for several components indicating that it will be very difficult to build the entire system unless further funds become available. (3) Analysis of features of neutron reflection from surfaces with special emphasis on the effect of surface roughness both on the specular beam and the diffusely ...

1991-11-01

334

Surface physics with cold and thermal neutron reflectometry  

Energy Technology Data Exchange (ETDEWEB)

Three aspects of the research project Surface physics with cold and ultracold neutron reflectometry'' were stressed during the present first year: (1) Setup of the reflectometer facility at the research reactor of the Rhode Island Nuclear Science Center. The installation provides a narrow pencil beam'' analyzed by time of flight using a chopper system. Following beam characterization and a test measurement of the total cross section of copper single crystal first reflectivity measurements are currently performed using a supermirror. (2) Design stud for the ultracold neutron imaging system, with involvement of the relevant industry. Bids are available for several components indicating that it will be very difficult to build the entire system unless further funds become available. (3) Analysis of features of neutron reflection from surfaces with special emphasis on the effect of surface roughness both on the ...

1991-11-01

335

Seismic migration and absorbing boundaries with a one-way wave system for heterogeneous media  

Energy Technology Data Exchange (ETDEWEB)

A first-order one-way wave system has been created based on characteristic analysis of the acoustic wave system and optimization of the dispersion relation. The authors demonstrate that this system is equivalent to a third-order scalar partial-differential equation which, for a homogeneous medium, reduces to a form similar to the 45{degree} paraxial wave equation. This system describes accurately waves propagating in a 2D heterogeneous medium at angles up to 75{degree}. The one-way wave system representing downgoing waves is used for a modified reverse time migration method. As a wavefield extrapolator in migration, the downgoing wave system propagates the reflection events backwards to their reflectors without scattering at the discontinuities in the velocity model. Hence, images with amplitudes proportional to reflectivity can be obtained from this migration technique. They present examples of the application of the new migration method to ...

1996-07-01

336

Investigation of texturization for crystalline silicon solar cells with sodium carbonate solutions  

Energy Technology Data Exchange (ETDEWEB)

We investigate a new texturization technique for crystalline silicon solar cells with sodium carbonate (Na{sub 2}CO{sub 3}) solutions. We show the dependence of the hemispherical surface reflectance on solution temperature, the etching time and the Na{sub 2}CO{sub 3} concentration. Furthermore, we investigate what element in Na{sub 2}CO{sub 3} solution influences the texturing for reducing the texturing time. As a result of experiments, we find it possible to get low reflectance in a shorter texturing time by the addition of NaHCO{sub 3}. The size of texture becomes smaller by the addition of NaHCO{sub 3} but the etching rate does not change. We conclude carbonic ion and/or its compound seems to play an important role as the initiator of pyramidal structure. This texturing method is cost effective because there is no need of expensive IPA, and the surface reflectance is reduced sufficiently in a short time. This method is ...

2000-04-01

337

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

Energy Technology Data Exchange (ETDEWEB)

Anisotropy has been investigated using S-wave as a technique for detecting fractures. In this study, fundamental experiments were carried out with slightly changing the measuring conditions at a place where anisotropy was expected. This paper describes the fundamental data acquisition of anisotropy analysis using S-wave, and a part of the results. The experiments were conducted on the agricultural road in Yamadera district, Matsuyama-machi, Yamagata Prefecture. Two flat unpaved roads meeting at right angles were used as traverse lines. In this place, several reflection surfaces were certainly detected by P-wave, and anisotropy of S-wave was confirmed from the velocity of refracted wave of S-wave. Data were processed for individual traverse lines meeting at right angles. Firstly, signal sweeping, correlation, and vertical superposition were made. Six kinds of data were prepared, i.e., three-component receiving records of data at 0{degree} of generating direction and ...

1996-10-01

338

Elastic modeling and steep dips: unraveling the reflected wavefield  

Energy Technology Data Exchange (ETDEWEB)

As part of a larger elastic numerical modeling project, we have been investigating how energy reflected from steeply dipping interfaces is recorded using typical multicomponent acquisition geometries. Specifically, we have been interpreting how rcflection events from the flanks of salt dome structures are distributed on 3C and 4C phones for vertical seismic profiles (VSPs) and ocean bottom seismic (OBS) or land surface surveys. The ultimate goal of this investigation is to improve the structural imaging of steeply dipping interfaces and eventually to evaluate the usc of the recorded elastic wavefield for fluid description near these interfaces. In the current work, we focus on a common assumption used when processing converted wave reflection seismic data that most PP energy is recorded on the vertical geophone and/or the hydrophone and that most PS energy is recorded on the horizontal geophones. This is a useful assumption when it is valid, ...

2003-01-01

339

Properties of cellulose solutions in methylmorpholine N-oxide containing montmorillonite nanoparticles and of composite films thereof  

British Library Electronic Table of Contents (United Kingdom)

Rheological properties of moderately concentrated solutions of cellulose in methylmorpholine N-oxide-dimethylformamide mixtures containing hydrophilic montmorillonite nanoparticles were studied. Film composite materials were prepared, and their physicomechanical properties and structural organization were studied.

2011-01-01

340

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

International Nuclear Information System (INIS)

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

341

Use of thin glass reflectors for solar concentrators  

Science.gov (United States)

Elastically deforming thin glass (thickness = 0.13 to 0.80 mm) provides an alternate method of forming a curved glass reflector which can eliminate some of the disadvantages of thicker glass. A concept is described where silvered thin glass is bonded to a steel backing to form a laminate with a reflectance greater than 93%. Subsequent bending of the flat reflector laminate to a concentrating profile produces compressive stresses throughout the glass if the laminate is properly designed. These compressive stresses enhance fracture resistance and the lamination provides protection for the silver. The design of the laminate is outlined for 0.25 and 0.51 mm thickness glass and fabrication procedures are discussed. Thermal/humidity cycling, hail impact, bond strength measurements and reflectance results are presented which demonstrate the performance capabilities of this reflector laminate concept.

1980-01-01

342

Towards the Soul: Percy Bysshe Shelley's Epipsychidion  

British Library Electronic Table of Contents (United Kingdom)

The period from the early eighteenth century up to 1820 witnesses a fundamental shift in the conception of the human. This shift is most clearly reflected in the soul's decline from being the essence of human life to a metaphor for the mind. At the same time, the status of the body rises from a machine to a whole organism that cannot only react but also act and think. This essay follows the discourse history of the soul from John Locke to Percy Bysshe Shelley, reflecting on the fact that the emergence of the modern scientific system at the end of the Romantic period and with it a biological conception of the human does not eventually lead to the end of the concept of soul. Rather, the soul becomes an important aesthetic concept in Romantic poetry. The analysis of the poem Epipsychidion sho...

2011-01-01

343

Strong coupled organic microcavities  

International Nuclear Information System (INIS)

Strong coupled organic-inorganic microcavities device has been realized and studied. One of the two cavities contains an organic thin film of tetrakis(4-methoxyphenyl)porphyrin, whereas the other microcavity is a dielectric structure coupled to the organic one by means of a LiF/ZnS Bragg mirror. Reflectivity spectra show the presence of two well defined cavity dips. We observe an energy splitting of the two cavity-modes. Despite only one cavity contains the active layer, the photoluminescence spectra display two peaks at the same energy of the reflectivity dips. These observations indicate the strong coupling of the two cavities. The comparison of the diagonalized effective Hamiltonian with the observed resonances further confirms the strong coupling.

2010-02-01

344

Simulation study on retention and reflection from tungsten carbide under high fluence of helium ions  

Energy Technology Data Exchange (ETDEWEB)

We have studied, by a Monte Carlo simulation code ACAT-DIFFUSE, the fluence-dependence of the amount of retained helium atoms in tungsten carbide at room temperature under helium ion bombardment. The retention behavior may be understood qualitatively in terms of irradiation-dependent diffusion coefficient assumed and range. The emission processes from tungsten carbide under helium ion irradiation derived were compared with each other. We have discussed the retention curves for incident energy of 5 keV at incident angles of 0deg and 80deg and of 500 eV at 0deg. The energy spectra of helium atoms reflected from tungsten carbide for incident energy of 500 eV at 0deg and 80deg were compared with those from graphite and tungsten. (author)

2000-08-01

345

Responses of the blister beetle Hycleus apicicornis to visual stimuli  

British Library Electronic Table of Contents (United Kingdom)

Insect attraction to host plants may be partly mediated by visual stimuli. In the present study, the responses of adult Hycleus apicicornis (Gur.) (Coleoptera: Meloidae) to plant models of different colours, different combinations of two colours, or three hues of blue of different shapes are compared. Single-colour models comprised the colours sky blue, bright green, yellow, red, white and black. Sky blue (reflecting light in the 440-500 nm region) is the most attractive, followed by white, which reflects light over a broader range (400-700 nm). On landing on sky blue targets, beetles exhibit feeding behaviour immediately. When different hues of blue (of different shapes) are compared, sky blue is preferred over turquoise, followed by dark blue, indicating that H. apicicornis is more attra...

2011-01-01

346

Rb-Sr isotopic studies on granodioritic rocks from the Mecsek mountains, Hungary  

Energy Technology Data Exchange (ETDEWEB)

New isotopic age determinations carried out with the rubidium-strontium method on granodioritic basement rocks from the Mecsek Mountains in Southeastern Transdanubia give further support to assumptions on a polyphase development of the Mecsek crystalline. As shown by initial Sr isotopic ratios, the protolith of the granodioritic assemblage of polymetamorphic-anatectic origin must have been strongly basic in its composition. The scatter of individual model ages obtained on total rock samples reflects the polymetamorphic-polytectonized character of the basement, and suggests that following a primary granitization process secondary events might have led to the total or partial recrystallization of the rocks in question. The tectonic development of the basement crystalline as reflected in the isotopic age data closed at about 270+-20 million years ago, with processes causing retrograde changes in the crystalline as a whole but leading to the ...

1981-01-01

347

Point-contact Andreev reflection spectroscopy of heavy-fermion-metal/superconductor junctions  

Energy Technology Data Exchange (ETDEWEB)

Our previous point-contact Andreev reflection studies of the heavy-fermion superconductor CeCoIn{sub 5} using Au tips have shown two clear features: reduced Andreev signal and asymmetric background conductance. To explore their physical origins, we have extended our measurements to point-contact junctions between single crystalline heavy-fermion metals and superconducting Nb tips. Differential conductance spectra are taken on junctions with three heavy-fermion metals, CeCoIn{sub 5}, CeRhIn{sub 5}, and YbAl{sub 3}, each with different electron mass. In contrast with Au/CeCoIn{sub 5} junctions, Andreev signal is not reduced and no dependence on effective mass is observed. A possible explanation based on a two-fluid picture for heavy fermions is proposed.

2008-04-01

348

Point contact Andreev reflection spectroscopy of NdFeAsO_0_._8_5  

International Nuclear Information System (INIS)

The newly discovered oxypnictide family of superconductors show very high critical temperatures of up to 55 K. Whilst there is growing evidence that suggests a nodal order parameter, point contact Andreev reflection spectroscopy can provide crucial information such as the gap value and possibly the number of energy gaps involved. For the oxygen deficient NdFeAsO_0_._8_5 with a T_c of 45.5 K, we show that there is clearly a gap value at 4.2 K that is of the order of 7 meV, consistent with previous studies on oxypnictides with lower T_c. In addition, taking the spectra as a function of gold tip contact pressure reveals important changes in the spectra which may be indicative of more complex physics underlying this structure. (rapid communication)

2008-09-01

349

Point -contact Andreev reflection spectroscopy of heavy-fermion-metal/superconductor junctions  

Energy Technology Data Exchange (ETDEWEB)

Our previous point-contact Andreev reflection studies of the heavy-fermion superconductor CeCoIn{sub 5} using Au tips have shown two clear features: reduced Andreev signal and asymmetric background conductance. To explore their physical origins, we have extended our measurements to point-contact junctions between single crystalline heavy-fermion metals and superconducting Nb tips. Differential conductance spectra are taken on junctions with three heavy-fermion metals, CeCoIn{sub 5}, CeRhIn{sub 5}, and YbAl{sub 3}, each with different electron mass. In contrast with Au/CeCoIn{sub 5} junctions, Andreev signal is not reduced and no dependence on effective mass is observed. A possible explanation based on a two-fluid picture for heavy fermions is proposed.

2008-01-01

350

Performance Evaluation of Several Types of Pulsed Eddy Current Probes for Detecting Wall Thickness Reduction  

Science.gov (United States)

In this paper, four different types of pulsed eddy current (PEC) probe are designed and their performance of detecting wall thickness reduction is compared. By using the backward difference method in time and the finite element method in space, PEC signals from various thickness and materials are numerically calculated and three features of the signal are selected. Since PEC signals and features are obtained by various types and sizes of probe, the comparison is made through the normalized features which reflect the sensitivity of the feature to thickness reduction. The normalized features indicate that the shielded reflection probe provides the best sensitivity to wall thickness reduction for all three signal features. Results show that the best sensitivity to thickness reduction is achieved by the peak value, but also suggest that the time to peak can be a good candidate because of its linear relationship with the thickness variation.

2010-02-01

351

Morphological characteristics and medium-term evolution of the beaches between Ceuta and Cabo Negro (Morocco)  

British Library Electronic Table of Contents (United Kingdom)

This work presents the results of a combined study on the beach morphology and the evolution at short- and medium-term of the littoral between Ceuta and Cabo Negro (Morocco). It is an interesting sector showing a great increase of human occupation and coastal structures. The monitoring program allowed for the reconstruction of the beach morphological behavior and the seasonal changes. The studied beaches presented reflective profiles recording little seasonality, with the most notable morphological changes being strictly related to storms. Surf Similarity and Surf Scaling parameters highlighted the existence of intermediate and reflective beach states, characterized by plunging breakers. Aerial photographs and a satellite image have been geo-referenced and elaborated with GIS tools to reco...

2007-01-01

352

Modification of the Gaussian dispersion equation to accommodate restricted lateral dispersion in deep river valleys  

Energy Technology Data Exchange (ETDEWEB)

Lateral plume dispersion in deep river valleys during neutral and stable lapse rate conditions can be exceptionally high due to the intense horizontal turbulence generated by prominent variations in the width, orientation and surface roughness of the valley walls. Use of the standard Gaussian dispersion equation to represent this enhanced lateral plume spread in a narrow valley may be inappropriate since consideration should also be given to the restriction of the horizontal plume spread due to impingement against the valley walls. The basic concept employed in the modification of the Gaussian dispersion equation was to assume that multiple eddy reflections occur between the valley walls in a manner similar to the vertical eddy reflections between the ground plane and an inversion layer aloft. The expressions are developed, but no attempt has been made to validate them with actual measured field data. 4 references, 3 figures, 1 table.

1986-02-01

353

Microwave transport in EBT distribution manifolds using Monte Carlo ray-tracing techniques  

Energy Technology Data Exchange (ETDEWEB)

Ray tracing Monte Carlo calculations have been carried out using an existing Monte Carlo radiation transport code to obtain estimates of the microsave power exiting the torus coupling links in EPT microwave manifolds. The microwave power loss and polarization at surface reflections were accounted for by treating the microwaves as plane waves reflecting off plane surfaces. Agreement on the order of 10% was obtained between the measured and calculated output power distribution for an existing EBT-S toroidal manifold. A cost effective iterative procedure utilizing the Monte Carlo history data was implemented to predict design changes which could produce increased manifold efficiency and improved output power uniformity.

1983-01-01

354

Long and Short Distance Migration in Italy: The Role of Economic, Social and Environmental Characteristics  

British Library Electronic Table of Contents (United Kingdom)

This paper analyses Italian interregional migration flows. The approach taken is to decompose labour mobility flows into short distance and long distance migration and to model the effects of economic variables, social capital and quality of life variables, and amenity variables, on the mobility behaviour of individuals. We estimate these different types of migration flows using a negative binomial model, augmented with instruments to control for potential endogeneity issues. Our findings demonstrate that long distance migration reflects a disequilibrium model of migration whereas short distance migration largely reflects an equilibrium model of migration. As such, attempts to model interregional migration in general will be mis-specified as the simultaneously-operating underlying mobility...

2011-01-01

355

Lithologic facies, seismic facies, and strike-slip setting of the lower carboniferous alluvial/fluvial/lacustrine Albert formation of New Brunswick. Geoscience report No. 92-2  

Energy Technology Data Exchange (ETDEWEB)

In the early 1980s, a program was begun to evaluate the oil shale resources of the Albert Formation by undertaking a geological lithofacies study of the Albert strata in the Moncton Subbasin of southeastern New Brunswick. Most rock exposures of the Albert were examined from 1982-84 and additional field work was carried out in the summers of 1989 and 1990. In January 1989, 1,900 km of Vibroseis seismic reflection profiles shot from 1981-84 by Chevron Canada Resources Ltd. in the Moncton and Sackville subbasins became publicly available. This report gives the results of the geological investigations on the Albert Formation in the southeastern Moncton Subbasin and the integration of interpreted seismic reflection profiles to help resolve some of the geological problems encountered.

1992-01-01

356

Light emission from hydrogen-copper interaction at grazing incidence  

Energy Technology Data Exchange (ETDEWEB)

The optical emission of excited H reflected from clean Cu(110) after impingement of H/sup +/ and H/sub 2//sup +/ in the energy range of 250 eV to 20 keV per nucleon at 70/sup 0/ angle of incidence to the surface normal was measured. For incident 10 keV H/sub 2//sup +/, the highest excited hydrogen state detected was the n=10 level. The Hsub(..cap alpha..) yield was found to be fluence and energy dependent. This effect is attributed either to fast sputtered hydrogen, surface roughness or to an increase with hydrogen concentration in electron states of p-like symmetry near the Fermi level of copper. The Hsub(..cap alpha..) yield per reflected nucleon shows approximately an exponential dependence on both projectile energy per nucleon and scattered particle reciprocal velocity perpendicular to the surface.

1984-03-01

357

Light emission from hydrogen-copper interaction at grazing incidence  

International Nuclear Information System (INIS)

The optical emission of excited H reflected from clean Cu(110) after impingement of H"+ and H_2"+ in the energy range of 250 eV to 20 keV per nucleon at 70"0 angle of incidence to the surface normal was measured. For incident 10 keV H_2"+, the highest excited hydrogen state detected was the n=10 level. The Hsub(#alpha#) yield was found to be fluence and energy dependent. This effect is attributed either to fast sputtered hydrogen, surface roughness or to an increase with hydrogen concentration in electron states of p-like symmetry near the Fermi level of copper. The Hsub(#alpha#) yield per reflected nucleon shows approximately an exponential dependence on both projectile energy per nucleon and scattered particle reciprocal velocity perpendicular to the surface. (orig.).

1983-07-01

358

Investigation of the unsteadiness of a shock-reflection interaction with time-resolved particle image velocimetry  

British Library Electronic Table of Contents (United Kingdom)

The spatio-temporal dynamics of an impinging shock/boundary layer interaction at Mach 2 and under incipient separation conditions, has been investigated experimentally by means of high-speed particle image velocimetry (PIV). The available PIV acquisition rate of up to 20 kHz permits a time-resolved characterization of the interaction. The dynamics of different flow regions?notably the separation region and the reflected shock?were quantified by means of temporal auto-correlation fields and pseudo-spectral analysis. The PIV data further enable to investigate the relationship between spatially extended flow features, such as shock position and bubble size, as well as the influence of the upstream boundary layer. The results confirm earlier studies that there is an important upstream effect o...

2011-01-01

359

Correlation and interpretation of three-component survey seismic anomalies, Zamora gas field, northern Sacramento Valley, California  

Energy Technology Data Exchange (ETDEWEB)

A three-component seismic line acquired over the Zamora gas field, northern Sacramento Valley, California, displays conventional (P-P) and converted-wave (P-SV) seismic anomalies. Well log and seismic modeling results indicate that bright-spot reflection strengths are related to variations in fluid saturation and lithology. The P-SV reflection strengths and interval velocities provide valuable information that complements more conventional strategies such as amplitude with offset and polarity analysis. This integrated strategy can improve risk evaluation and well-site selection in areas where rapid changes in reservoir quality impact resource evaluation.

1989-03-01

360

Correlation and interpretation of three-component survey seismic anomalies, Zamora Gas field, northern Sacramento Valley, California  

Energy Technology Data Exchange (ETDEWEB)

A three-component seismic line acquired over the Zamora gas field, northern Sacramento Valley, California, displays conventional (P-P) and converted-wave (P-SV) seismic anomalies. Well log and seismic modeling results indicate that bright-spot reflection strengths are related to variations in fluid saturation and lithology. The converted-wave reflection strengths and interval velocities provide valuable information that compliments more conventional strategies such as amplitude with offset and polarity analysis. This integrated strategy can improve risk evaluation and well site selection in areas where rapid changes in reservoir quality impact resource evaluation.

1989-04-01

361

Centennial climate variability in the British Isles during the mid-late Holocene  

British Library Electronic Table of Contents (United Kingdom)

Multi-millennial climate changes were relatively minor over the mid-late Holocene in the British Isles, because orbitally forced insolation changes were smaller than those at higher latitudes. Centennial climate variability is thus likely to have exerted a greater influence on the environment and human society of the region. Proxy-climate records from the British Isles covering the last 4500years are assembled and re-evaluated with the aim of identifying centennial climate variability reflected by multi-proxy indicators. The proxies include bog oak populations, peatland surface wetness, flooding episodes from fluvial deposits, speleothem annual band width and oxygen isotopes, chironomids from lake sediments and sand and dune deposition. Most proxies reflect water balance rather than temper...

2010-01-01

362

Broad-linewidth laser absorption measurements of oxygen between 211 and 235nm at high temperatures  

British Library Electronic Table of Contents (United Kingdom)

Absorption coefficient data are presented for molecular oxygen at temperatures between 1100 and 2000K and discrete wavelengths between 211 and 235nm. Measurements were made behind reflected shock waves using broad-linewidth ultraviolet laser radiation generated from a frequency-quadrupled, tunable, pulsed Ti:Sapphire laser. Test mixtures consisting of 15% O"2, 15% He and balance Ar were used to minimize the influence of vibrational relaxation on the reflected shock temperature. The experimental results are in good agreement with theoretical calculations and confirm that discrete features from the Schumann-Runge system dominate between 211 and 235nm at temperatures higher than 1100K.

2011-01-01

363

Assessing vineyard water status using the reflectance based Water Index  

British Library Electronic Table of Contents (United Kingdom)

In the Mediterranean arc, vines for wine production are mainly grown without the support of irrigation. Under such conditions, site variables affecting the extent and seasonal timing of water deficits are the dominant environmental constraints for grape production. Moreover, water availability and vine water status are the factors most comprehensively determining fruit composition and, thus, wine quality. Therefore, monitoring the extent of water stress in vines might be a valuable tool for the optimisation of grape yield and quality. The objective of this study was to evaluate the feasibility of using the reflectance based Water Index (WI) to estimate vine water status at the leaf and canopy levels. The study was conducted on Vitis vinifera cv. Chardonnay potted plants submitted to contra...

2010-01-01

364

Andreev reflection spectroscopy in MgB{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

Our Andreev reflection measurements (Phys. Rev. Lett. 87 (2001) 137005) along with other experiments have led to a general consensus that MgB{sub 2} is a multiband superconductor with two main superconducting gaps closing at the same T{sub c}. Here we show the behavior of the small gap as a function of the temperature and magnetic field. This gap is isotropic with T{sub c} of the bulk material but with a specific small (crossover) critical magnetic field of about 1 T much lower than the real H{sub c2}. The latter field is anisotropic and is rather governed by the large gap and strongly anisotropic Fermi surface of the material.

2003-04-01

365

CRC materials science and engineering handbook. Third edition  

Energy Technology Data Exchange (ETDEWEB)

This definitive reference is organized in an easy-to-follow format based on materials properties. It features new and existing data verified through major professional societies in the materials fields, such as ASM International and the American Ceramic Society. The third edition has been significantly expanded, most notably by the addition of new tabular material for a wide range of nonferrous alloys and various materials. The contents include: Structure of materials; Composition of materials; Phase diagram sources; Thermodynamic and kinetic data; Thermal properties of materials; Mechanical properties of materials; Electrical properties of materials; Optical properties of materials; Chemical properties of materials.

1999-01-01

366

The Elastic Properties of the Cryptococcus neoformans Capsule  

UK PubMed Central (United Kingdom)

AbstractMicrobial capsules are important for virulence, but their architecture and physical properties are poorly understood. The human pathogenic fungus Cryptococcus neoformans...Full Text Available

2009-08-19

367

Search Results - NASA Technical Reports Server  

Science.gov (United States)

The influence of ablation on stagnation region convective heating for ... and thermal properties of this fiber depend on the fluorination process ... However, these properties are between those of graphite and those of PTFE (Teflon). ...

368

Property and Microstructural Nonuniformity in the Yttrium-Barium ...  

Science.gov (United States)

Pore Fraction in Yttrium-Barium-Copper-Oxide and. Other Polycrystalline. Materials ...... Properties of Yttrium Ceramic. Sov. J. LowTemp.Phys. 14:395-402 . ...

369

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 ...

1987-01-01

370

A comparison of the X-ray properties of X Per and gamma Cas  

Energy Technology Data Exchange (ETDEWEB)

The X-ray properties of the main sequence Be stars conclude that they are a widely separated binary system containing an accreting neutron star.

1982-04-01

371

8 - NASA Technical Reports Server  

Science.gov (United States)

The influence of ablation on stagnation region convective heating for ... and thermal properties of this fiber depend on the fluorination process ... However, these properties are between those of graphite and those of PTFE (Teflon). ...

372

3 - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011... properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. ...

373

Vector Velocity Imaging Using Cross-Correlation and Virtual Sources  

DEFF Research Database (Denmark)

Previous investigations have shown promising results in using the directional cross-correlation method to estimate velocity vectors. The velocity vector estimate provides information on both velocity direction and magnitude. The direction is estimated by beamforming signals along directions in the range $[0^{\\circ}; 180^{\\circ}[$ and identifying the direction that produces the largest correlation across emissions. An estimate of the velocity magnitude is obtained from the spatial shift between signals beamformed along the estimated direction. This paper expands these investigations to include estimations of the vector velocities of a larger region by combining the estimations along several scan lines. In combination with a B-mode image, the vector velocities are displayed as an image of the investigated region with a color indicating the magnitude, and arrows showing the direction of the flow. Using the RASMUS experimental ultrasound scanner, measurements have ...

2006-01-01

374

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

Energy Technology Data Exchange (ETDEWEB)

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

2003-06-01

375

Three-dimensional rotational angiography of the carotid arteries with high-flow injection from the aortic arch. Preliminary experience  

International Nuclear Information System (INIS)

Purpose: Three-dimensional rotational angiography (3DRA) is a new technique based on a rotational angiographic acquisition able to display arterial vessels in a 3D rendering mode. The system was mainly developed for neuroradiological evaluations but preliminary extracranial experiences have also been reported. The aim of our work was to compare the results of three-dimensional angiography of the carotid arteries done with high-flow injection of contrast medium from the aortic arch with the results of selective angiography. Materials and methods: Twenty patients underwent digital angiography of the supra-aortic vessels in order to quantify a stenosis of the carotid bifurcations previously detected at Doppler Ultrasound. Examinations were performed with the Philips Integris Allura system provided with the rotational angiography (RA) tool connected to a workstation for three-dimensional reconstruction able to display vessels in a 3D fashion (Volume Rendering, Shaded ...

376

The value of high-resolution MR-imaging for the staging of malignant lesions of tongue, pharynx and larynx; Klinische Wertigkeit der hochaufloesenden Magnetresonanztomographie beim Staging von Tumoren der Mundhoehle, des Pharynx und des Larynx  

Energy Technology Data Exchange (ETDEWEB)

In a prospective study 102 patients with malignant tumors of the tongue, oropharynx, hypopharynx, and larynx were staged by means of MRI. Special attention was directed at those tumour extensions that could influence the treatment strategy. The MR findings were correlated with the results of palpation, endoscopy, ultrasound, computerised tomography and histopathological findings. MRI showed a good delineation of pT{sub 2} to pT{sub 4} tumours. However, visualisation of small tumours in the soft palate, the tonsils, the pyriform sinuses and vocal cords was difficult. In conclusion our results suggest that in addition to endoscopy MRI is a valuable tool for the examination of tumours of tongue, oropharynx, hypopharynx and larynx. (orig.) [Deutsch] In einer prospektiven Studie wurden 102 Patienten mit malignen Tumoren der Mundhoehle, des Oro- und Hypopharynx sowie des Larynx mit der Mgnetresonanztomographie (MRT) untersucht, wobei besonders Wert auf die Bestimmung ...

1994-02-01

377

The Primary Patency and Fracture Rates of Self-Expandable Nitinol Stents Placed in the Popliteal Arteries, Especially in the P2 and P3 Segments, in Korean Patients  

Energy Technology Data Exchange (ETDEWEB)

We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for steno occlusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2: n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at ...

2011-04-15

378

Technetium-99m DISIDA hepatobiliary agent in diagnosis of hepatocellular carcinoma: relationship between detectability and tumor differentiation  

Energy Technology Data Exchange (ETDEWEB)

The present investigation was aimed to assess the usefulness of biliary agents scintigraphy in the diagnosis of hepatocellular carcinoma (HCC) and to ascertain the relationship between the uptake of these agents and the degree of HCC differentiation. Forty-four patients with this hepatic cancer were included in the study. Liver scans were performed 20 min and 3 hr after the administration of 99mTc diisopropyliminodiacetic acid (DISIDA). DISIDA scintigraphy could not be assessed in six cases. In 16 (42%) out of the remaining 38 patients, the tumor exhibited equal or greater radioactivity uptake than the surrounding liver. In six out of these 16 patients, tumor uptake was apparent in the early and delayed hepatic scans, while in the other ten subjects radioactivity uptake by the HCC could only be detected in the 3-hr delayed scans. In the remaining 22 patients, HCC appeared as a cold area. Tumor location by this technique did not differ from that observed by 99mTc-sulfur colloid scan or ...

1988-12-01

379

Special phased array applications for pipeline girth weld inspections  

Energy Technology Data Exchange (ETDEWEB)

Pipeline automated ultrasonic testing (AUT) uses fully automated equipment that travels around a pipe on a welding band in a linear scan to allow array pulses to provide ultrasound information on weld zones. Pipeline AUT is also used for zone discrimination as well as with special calibration blocks, dual gate output displays, and rapid defect sizing. AUT allows for the inspection of welds soon after completion, and can save construction costs by process control when combined with engineering critical assessment (ECA) to minimize rejection rates. Ultrasonic phased arrays (UPA) use an array of elements that are all individually wired, pulsed, and time-shifted. Elements are pulsed in groups of approximately 16 elements at a time for pipeline welds. Phased arrays can be used to combine electronic scanning, sectorial scanning and precision focusing to give a practical combination of displays. Optimum angles can be selected for welds and other components, and the ...

2004-07-01

380

Radiofrequency Ablation of Intrahepatic Cholangiocarcinoma: Preliminary Experience  

International Nuclear Information System (INIS)

The purpose of this study was to evaluate the safety and efficacy of percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) in patients with intrahepatic cholangiocarcinoma (ICCA) in a small, nonrandomized series. From February 2004 to July 2008, six patients (four men and two women; mean age 69.8 years [range 48 to 83]) with ICCA underwent percutaneous US-guided RFA. Preintervetional transarterial embolization was performed in two cases to decrease heat dispersion during RFA in order to increase the area of ablation. The efficacy of RFA was evaluated using contrast-enhanced dynamic computed tomography (CT) 1 month after treatment and then every 3 months thereafter. Nine RFA sessions were performed for six solid hepatic tumors in six patients. The duration of follow-up ranged from 13 to 21 months (mean 17.5). Posttreatment CT showed total necrosis in four of six tumors after one or two RFA sessions. Residual tumor was observed in two patients with larger ...

2010-08-01

381

Longitudinal changes in extended roles in radiography  

Energy Technology Data Exchange (ETDEWEB)

Purpose: The purpose of this research was to identify the extent and scope of changes to radiography practice. Method: Questionnaires were sent to radiology managers at acute National Health Service (NHS) hospitals in 2000 as a follow-up to an initial survey conducted in 1998. Information was sought on region, teaching/non-teaching status, the nature of extended role tasks undertaken and the year in which these tasks were first undertaken. Results: Some 172 questionnaires were returned from a total of 253 dispatched (68%). In 161 hospitals radiographers administered intravenous injections and performed barium enemas in 119 hospitals, while a red-dot system was in operation in 141 hospitals. Reporting by radiographers had increased since 1998. Replies indicated that, at 124 hospitals, radiographers were reporting in ultrasound. Skeletal reporting was the second most-frequently-reported activity, with 63 hospitals indicating that radiographers reported in this ...

2002-11-01

382

Infrarenal abdominal aortic aneurysm. Endovascular repair with stent grafts; Infrarenales Bauchaortenaneurysma. Endovaskulaere Stent-Graft-Therapie  

Energy Technology Data Exchange (ETDEWEB)

As an alternative to surgery, endovascular therapy with stent grafts has become the second main treatment option for infrarenal abdominal aortic aneurysms. Unlike surgery, endovascular treatment with stent grafts is also applicable in patients unfit for open repair. Despite current improvements in endovascular repair devices, significant anatomic barriers still exclude this technique for a large number of patients. Computed tomography, magnetic resonance imaging, and ultrasound are essential for diagnostics, preintervention planning, and postintervention follow-up of abdominal aneurysms treated with stent grafts. This review covers etiology, pathology, and diagnostic aspects. Materials and methods for endovascular treatment of abdominal aortic aneurysms are presented in detail, and clinical results and complications are discussed. (orig.) [German] Die endovaskulaere Therapie des infrarenalen Bauchaortenaneurysmas hat sich als Alternative zur offenen chirurgischen ...

2008-09-15

383

Image-guided pleural biopsy: diagnostic yield and complications  

International Nuclear Information System (INIS)

Background: Pleural biopsy and cytology are standard procedures for the investigation of pleural disease. Recent medical literature has suggested that image-guided pleural biopsy shows improved sensitivity for the diagnosis of pleural malignancy, when compared with the more commonly performed reverse bevel needle biopsy such as Abrams' needle. In our centre there has been an increasing trend towards performing image-guided pleural biopsies, and to our knowledge there is no large published series documenting the complication rate and diagnostic yield. Methods: The radiology and pathology databases were searched for all image-guided [computed tomography (CT) and ultrasound (US)] pleural biopsies from January 2001 to December 2004. All imaging and histology were reviewed, and final diagnostic information about patients was obtained from the respiratory multidisciplinary team database and patient notes. A record was made of complications following biopsy, presence of ...

2006-08-01

384

Clinical Significance of Renal Pelvic Dilatation less than 10 mm in Neonates: Correlation with Urinary Tract Infection and Vesicoureteral Reflux  

Energy Technology Data Exchange (ETDEWEB)

We wanted to evaluate the correlation of mild renal pelvic dilatation (RPD) that is observed to be less than 10 mm on ultrasound (US) with urinary tract infection (UTI) and vesicoureteral reflux (VUR) in neonates. We reviewed 137 kidneys of 107 neonates who had RPD less than 10 mm on US. All the kidneys were divided into two groups: Group I (RPD <= 5.0 mm) and Group II (RPD > 5.0 mm), and we statistically analyzed the RPD change according to UTI and VUR. Seven neonates had VUR (5.1%), and there was no statistical significance between Group I (6 neonates, 5.6%) and Group II (1 neonate, 3.3%). Thirty seven cases (27%) had UTI and there was no statistical significance between Group I (30 cases, 28.0%) and Group II (7 cases, 23.3%). The RPD did not change in 81.8% of the cases, it increased in 4.4% of the cases and it decreased in 13.9% of the cases on follow up US. The incidence of VUR and UTI were not different according to the change of RPD. There were ...

2009-12-15

385

Accuracy of single versus combined use of ultrasonography or computed tomography in the localization of parathyroid adenoma  

International Nuclear Information System (INIS)

Objective was to assess the accuracy of a single versus combined use of ultrasound (US) or computed tomography (CT) in the localization of diseased parathyroid glands. Forty-one patients with hyper-parathyroidism treated surgically between January 2000 to December 2005 at Jordan University Hospital, Amman, Jordan were included in this study. Preoperative ultrasonographic and CT findings were reviewed and compared to the intraoperative and pathologic diagnosis of diseased parathyroid glands. The mean age of patients was 46 years (range 16-70; 15 males and 26 females). Parathyroid adenoma was confirmed in 33 patients and hyperplasia of the parathyroid glands in 8 patients. Preoperative evaluation was carried out in 32 patients (CT scan) and in 23 patients (US). In 18 cases, the diagnosis of parathyroid disease was based on CT findings alone and in 9 patients the diagnosis was based on a single US finding. Combined CT and US evaluation was carried out in 14 cases and ...

386

What is `that'?  

British Library Electronic Table of Contents (United Kingdom)

Davidsons paratactic account of indirect speech exploits the fact that `that' can be either a demonstrative pronoun or a subordinating conjunction. Davidson thinks that the fact that it is plausible to think that it inherited the latter function from the former lends support to his account. However, in other languages the two functions are performed by unrelated words, which makes the account impossible to apply to them. I argue that this shows that, rather than revealing the underlying form of indirect reports, the account reflects only a quirk of English.

2011-01-01

387

Visual search behaviour in skeletal radiographs: a cross-speciality study  

Energy Technology Data Exchange (ETDEWEB)

Aim: To determine whether experience improves the consistency of visual search behaviour in fracture identification in plain radiographs, and the effect of specialization. Material and methods: Twenty-five observers consisting of consultant radiologists, consultant orthopaedic surgeons, orthopaedic specialist registrars, orthopaedic senior house officers, and accident and emergency senior house officers examined 33 skeletal radiographs (shoulder, hand, and knee). Eye movement data were collected using a Tobii 1750 eye tracker with levels of diagnostic confidence collected simultaneously. Kullback-Leibler (KL) divergence and Gaussian mixture model fitting of fixation distance-to-fracture were used to calculate the consistency and the relationship between discovery and reflective visual search phases among different observer groups. Results: Total time spent studying the radiograph was not significantly different between the groups. However, the expert groups had a ...

2007-11-15

388

The first insertion devices at SSRL - some personal recollections  

Energy Technology Data Exchange (ETDEWEB)

The author recounts his experiences with insertion devices at the Stanford Synchrotron Radiation Laboratory. His first experiences with wigglers occured at the Cambridge Electron Accelerator, and was carried over to SSRL with the proposal for a six pole electromagnetic wiggler. Most modern undulators, and many wigglers are now designed around permanent magnets, and the origin of this transition at SSRL was rather fortuitous and humorous. It reflects some of the personality characteristics of Klaus Halbach.

1995-02-01

389

The detection and characterization of natural fractures using P-wave reflection data, multicomponent VSP, borehole image logs and the in-situ stress field determination  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this project are to detect and characterize fractures in a naturally fractured tight gas reservoir, using surface seismic methods, borehole imaging logs, and in-situ stress field data. Further, the project aims to evaluate the various seismic methods as to their effectiveness in characterizing the fractures, and to formulate the optimum employment of the seismic methods as regards fracture characterization.

1995-04-01

390

Synchronized Observations of Bubble Growth and Microlayer Evaporation in Horizontal Pool Boiling  

International Nuclear Information System (INIS)

The present study is aiming at the visualization of the boiling structures for various pool boiling and flow boiling conditions by applying multiple visualization techniques simultaneously. The bubble growth rate and microlayer behavior were simultaneously visualized for an isolated boiling regime of a water by using a shadow graph and a total reflection technique, respectively

2010-10-01

391

Stabilization of measuring channel of reflective gamma thickness gage by light pulses from additional scintillator  

International Nuclear Information System (INIS)

Possibility for using a sodium iodide scintillator as a reference signal source is considered. Experimental data on studying the performance of a gamma thickness gage with an additional scintillator are given. Results of experimental investigations of a thickness gage dummy proved practical expediency of the principle being considered. It is established, in particular, that the device is ready to operate without warm-up with a constant sensitivity, the deviation not exceeding 0.5%, in the ambient temperature range of 15-25 deg C.

392

Reliability analysis of diesel generators of Wolsung unit 1  

Energy Technology Data Exchange (ETDEWEB)

As a maintenance optimization project to improve the safety of Wolsung NPP (Nuclear Power Plant), reliability of diesel generators are estimated based on the operating experience, and improvement options are suggested. A reliability measure is suggested for the estimation of reliability for standby safety systems to reflect availability. It is assessed that the reliability of diesel generators can be mush improved if the suggested improvement options are implemented. (Author) 6 refs., 1 tab.

1997-05-01

393

Reliability analysis of diesel generators of Wolsung Unit 1  

Energy Technology Data Exchange (ETDEWEB)

As a maintenance optimization project to improve the safety of Wolsung NPP (Nuclear Power Plant), reliability of diesel generators are estimated based on the operating experience, and improvement options are suggested. A reliability measure is suggested for the estimation of reliability for standby safety systems to reflect availability. It is assessed that the reliability of diesel generators can be much improved if the suggested improvement options are implemented.

1997-05-01

394

Radioactive and stable isotope geology  

Energy Technology Data Exchange (ETDEWEB)

Aimed at post-graduate and post-doctoral researchers in geochemistry, this book reflects the rapid changes in the applications of radioactive and stable isotope analysis to a range of geological and geochemical problems. Isotropic chemistry and methods used in mass spectroscopy are discussed initially. The second section deals with radiometric dating methods. The role of isotopes in climate and environmental research is also explored. The book closes with a section on extra-terrestrial matter, geothermometry and the isotopic geochemistry of the Earth`s lithosphere. (UK).

1997-10-01

395

QUEST2: Project plan for preliminary analysis/system architecture phase (PA/SA)  

Energy Technology Data Exchange (ETDEWEB)

This Project Management Plan combines the project management deliverables from the P+ methodology that are applicable to this part of the QUEST2 work. This consolidation reflects discussions with WHC QA regarding an appropriate method for ensuring that P+ deliverables fulfill the intent of WHC-CM-3-10 and QR-19.

1995-03-08

396

Processing of multi-component crosshole reflection data by multi-mode crosshole migration (1): Theoretical study  

Energy Technology Data Exchange (ETDEWEB)

A theoretical background of crosshole reflection imaging with pre stack, multi-mode reverse time migration has been investigated. The crosshole migration has been carried out by solving two-way scalar wave equation with finite difference approximation. The wave field extrapolation was performed backward in time, with the imaging condition applied at each extrapolation time step to create partial image of the reflector. The complete migrated image was obtained by adding all the partial images from each time step. With multi-component crosshole data available, it is possible to separate the recorded data into primary P- and S-wave field. Separating wave field before migration is helpful in enhancing migrated image quality since only one wave mode can be dealt at a time with the scalar wave equation. It is possible to migrate mixed-mode primary reflections(P-S and S-P) as well as pure mode ones. These multi-mode migrations provide not only image ...

1993-08-31

397

Multi-mode wavepath depth imaging for the SEG/EAGE salt model  

Energy Technology Data Exchange (ETDEWEB)

Elastic depth imaging of both P-wave and S-wave prestack seismic reflection data is formulated as a degraded form of Kirchhoff migration known as Wavepath Migration (WM). Applications to the SEG/EAGE salt model show that the method is sufficiently versatile anti relaitively inexpensive. It handles S-wave data with at least the same accuracy as Pwave data when local mode conversions are removed. WM also provides an understanding of multi-mode illumination.

2003-01-01

398

Monte Carlo design calculations for a neutron imaging facility collimator  

Energy Technology Data Exchange (ETDEWEB)

A thermal neutron imaging facility for computed tomography and real-time neutron radiography is being developed at the University of Texas at Austin. The TRIGA reactor is a graphite-reflected Mark It pool-type research reactor. The neutron imaging facility will use beam port, which is at one end of a through part. Monte Carlo calculations were used to design the neutron collimator for this facility.

1996-12-31

399

Laser applications. Final report  

Energy Technology Data Exchange (ETDEWEB)

Processes were developed that use lasers as manufacturing tools. These processes were stripping of insulation from cables and wires, machining of quartz, microdrilling and welding of reflective metals, and precision alignment of curved surfaces before machining. A technological basis also was formed which resulted in a process for automatic surface inspection of parts and aided development of machining processes for Kevlar parts.

1980-07-01

400

Iodine-123-labeled pH shift brain-imaging agents  

International Nuclear Information System (INIS)

HIPDM is an "1"2"3I-labeled agent with a distribution in brain reflecting regional perfusion. This compound is neutral and lipid soluble at blood pH and freely crosses the blood-brain barrier. At the lower pH in brain, it picks up a hydrogen ion and becomes positively charged. In this form the molecule is not lipid soluble and it is trapped in brain.

1982-05-03

401

Investigation of Moessbauer radiation diffraction on Fe/sub 3/BO/sub 6/ monocrystal. Nuclear transition interference  

Energy Technology Data Exchange (ETDEWEB)

Energy spectra of the Bragg reflection of the Moessbauer ..gamma..-radiation from the /sup 57/Fe/sub 3/BO/sub 6/ weakly ferromagnetic monocrystal are studied. A strong effect of the interference transitions in iron nuclei, being in non-equivalent positions, on the spectra form is revealed. The measurement results are compared with theoretical calculations.

1984-05-25

402

Intrinsic and extrinsic crossluminescence in ionic crystals  

Energy Technology Data Exchange (ETDEWEB)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF{sub 2} was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br{sup -}) or the final (RbCl:Cs{sup +}; KCl:Cs{sup +}) state of CRL by doping. (author).

1991-01-01

403

Intrinsic and extrinsic crossluminescence in ionic crystals  

International Nuclear Information System (INIS)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF_2 was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br"-) or the final (RbCl:Cs"+; KCl:Cs"+) state of CRL by doping. (author).

1990-09-03

404

Influence of microwaves on the order parameter relaxation time of superconducting aluminium  

Energy Technology Data Exchange (ETDEWEB)

Experimentally it is found that at constant temperature the order-parameter relaxation time, tausub(..delta..), decreases with increasing power of the microwaves, coupled into a superconducting strip. If the same increase in critical current, that corresponds with a given power of the microwaves, is obtained by lowering the temperature, the decrease in tausub(..delta..) is smaller. This reflects the fact that quasiparticles are removed more efficiently from the gap edge by microwaves than by lowering the temperature in equilibrium. A modified time-dependent Ginzburg-Landau equation is shown to describe these results adequately.

1982-04-01

405

Inclusive Education for Students with Disabilities in Nigeria: Benefits, Challenges and Policy Implications  

Science.gov (United States)

This article analyzes the philosophical, sociological, and legal imperatives of including students with disabilities in ordinary schools. Some important global events that support inclusive education are discussed. The author reflects on Nigeria's newly revised National Policy on Education with its emphasis on inclusive education (2008), and the Universal Basic Education policy (1999). The article concludes with recommendations to improve the status quo.

2007-12-01

406

Hypotheses on forest decline as reflected by the results of surveys  

Energy Technology Data Exchange (ETDEWEB)

With reference to three hypotheses on the causes of forest decline, the manifold uses of forest decline surveys are demonstrated. Hypothesis no. 1: Forest disease from high-voltage transmission lines; hypothesis no. 2: Forest disease as the consequence of damage from micorrhizas; hypothesis no. 3: Radioactivity as the cause of the increased incidence of forest disease. (orig./MG)

1987-11-25

407

Heat exchange in a multi-cavity volumetric solar receiver  

Energy Technology Data Exchange (ETDEWEB)

The concept of a multi-cavity volumetric solar receiver is very attractive for the profitability of certain of its characteristics such as high efficiency and economy. The absorber is based on a pack of small ceramic cavities which intercept and absorb the inherent high solar flux reflected from an array of mirrors. Atmospheric air acts as a coolant medium when it is drawn through the pack. A model for an overall heat transfer performance of the receiver is given and numerically solved.

1991-01-01

408

Geologic research of conventional and unconventional hydrocarbon resources. Quarterly report, October 1, 1992--March 1, 1993  

Energy Technology Data Exchange (ETDEWEB)

This report covers the period from October 1, 1992 to March 1, 1993. The overall goals of the program task are to provide a final synthesis of six deep seismic reflection profiles and other geological and geophysical data from the southern Washington Cascades region where a probable extensive deep sedimentary basin has been discovered. This deep sedimentary basin is hypothesized from geological, regional magnetotelluric (MT), gravity, magnetic , and seismic reflection data as described in the American Association of Petroleum Geologists (AAPG) article by Stanley and others (1992). This report analyzed three seismic reflection profiles acquired by the Morgantown Energy Technology Centers in combination with the extensive MT and other data to outline a probable geological model for a thick conductive section of rocks in the southern Washington Cascades (called the Southern Washington Cascades conductor, SWCC). Earlier MT ...

1993-03-02

409

Fracture inspection by BHTV logging through a vinyl chloride tube; Enbi pipe ga sonyusareta kosei deno BHTV ni yoru kiretsu chosa  

Energy Technology Data Exchange (ETDEWEB)

A borehole televiewer (BHTV) logging was conducted to investigate cracks in bored wells. The logging process shoots ultrasonic waves onto bore walls and utilizes reflection waves from the bore walls. If the bores are filled with muddy water, or the ultrasonic waves can pass through even if vinyl chloride tubes have been inserted after excavation, the state of the bore walls can be investigated in principle. Conventional optical scanners are, however, incapable of making this investigation. The BHTV logging can be used for identifying lithofacies from reflection intensities from bore walls (it depends on sound impedance of rocks), not to speak of finding cracks. As a result of making logging upon setting time windows from 105 to 145 {mu} sec in a bored well inserted with a vinyl chloride tube, cracks in the bore wall were identified clearly through the vinyl chloride tube. If the distance between the bore wall and the vinyl chloride tube becomes ...

1997-05-27

410

External reflection absorption infrared spectroscopy study of lung surfactant proteins SP-B and SP-C in phospholipid monolayers at the air/water interface.  

UK PubMed Central (United Kingdom)

The interactions of the hydrophobic pulmonary surfactant proteins SP-B and SP-C with 1,2-dipalmitoylphosphatidylcholine in mixed, spread monolayer films have been studied in situ at the air/water interface...Full Text Available

1995-12-01

411

Exploiting industrial robotics  

International Nuclear Information System (INIS)

Advances in robotic technologies reflected in commercially available and demonstrated capabilities provide exceptional alternatives to the designer of new and upgraded production processes. This paper discusses the states of the art of these technologies, describes some of the research and application engineering which has extended and exploited these capabilities, and provides some conceptual synthesis of advanced robotics and other industrial automation to hypothetical nuclear industry/laboratory tasks. Nuclear industry applications are oriented upon tasks in hazardous and contaminating environments and with hazardous materials.

1990-01-15

412

Development document for proposed effluent limitations guidelines, new source performance standards, and pretreatment standards for the steam electric point source category. Interim report  

Science.gov (United States)

This document provides a technical basis for the revision of chemical effluent limitations guidelines for the Steam Electric Power Industry reflecting the Best Available Technology Economically Achievable (BATEA) for existing sources, New Source Performance Standards (NSPS) and Pretreatment Standards. The analysis of pollutants and the technologies applicable to their control has been based on specific waste streams of concern.

1980-09-01

413

Determination of anisotropic velocity model by reflection tomography of compression and shear modes; Determination de modele de vitesse anisotrope par tomographie de reflexion des modes de compression et de cisaillement  

Energy Technology Data Exchange (ETDEWEB)

As the jump from 2D to 3D, seismic exploration lives a new revolution with the use of converted PS waves. Indeed PS converted waves are proving their potential as a tool for imaging through gas; lithology discrimination; structural confirmation; and more. Nevertheless, processing converted shear data and in particular determining accurate P and S velocity models for depth imaging of these data is still a challenging problem, especially when the subsurface is anisotropic. To solve this velocity model determination problem we propose to use reflection travel time tomography. In a first step, we derive a new approximation of the exact phase velocity equation of the SV wave in anisotropic (TI) media. This new approximation is valid for non-weak anisotropy and is mathematically simpler to handle than the exact equation. Then, starting from an isotropic reflection tomography tool developed at Lt-'P, we extend the isotropic bending ray ...

2001-12-01

414

Detecting Sugarcane yellow leaf virus infection in asymptomatic leaves with hyperspectral remote sensing and associated leaf pigment analysis  

Science.gov (United States)

Sugarcane yellow leaf caused by Sugarcane yellow leaf virus (ScYLV) does not produce visual symptoms in most susceptible plants until late in the growing season. An experiment was conducted to determine if leaf reflectance and pigment analysis could be used to determine ScYLV infection prior to sym...

415

Depth profile of uncompensated spins in an exchange bias system  

Energy Technology Data Exchange (ETDEWEB)

We have used the unique spatial sensitivity of polarized neutron and soft x-ray beams in reflection geometry to measure the depth dependence of magnetization across the interface between a ferromagnet and antiferromagnet. The new uncompensated magnetization near the interface responds to applied field, while the uncompensated spins in the antiferromagnetic bulk are pinned, thus providing a means to establish exchange bias.

2005-05-17

416

Depth of origin of the gas content in thermal waters  

Energy Technology Data Exchange (ETDEWEB)

The gas composition of recent thermal waters is in perfect conformity with their geologic-tectonic positions. The composition of gas-liquid inclusions in the basic-hyperbasic xenoliths of basaltoid lavas depends on the depth from which xenoliths are supplied. (The depth is determined by using the methods of geological thermobarometers). By comparing available data the conclusion was drawn that the gas compositions of thermal waters reflect the depth of generation of deep fluid which heats them and depends on the penetration depth of the fluid-conducting fissure zones.

1980-01-01

417

Computed tomography in migratory disorders of human brain development  

International Nuclear Information System (INIS)

Computed tomographic findings in developmental brain anomalies are more easily classified when the system used is based on embryogenesis related to morphology. Analysis of computed tomographic findings in a series of 154 patients with brain anomalies (Chiari malformation not included) revealed that specific examples of abnormalities occurring in major stages of brain development may be recognized by computed tomography. This paper deals with a group of patients with abnormalities that reflect a disturbance in neuronal migration. (orig.).

418

Chronic fatigue syndrome, XMRV and blood safety  

British Library Electronic Table of Contents (United Kingdom)

In the past few months, there has been public discussion relating to a new perspective on blood safety and specifically upon measures to prevent or discourage donation by individuals with a diagnosis of myalgic encephalopathy-chronic fatigue syndrome. This reflects an intriguing interplay between science, public health and public concern and illustrates some of the difficulties of making decisions in the face of uncertainty and inadequate information.

2011-01-01

419

Calculation method for microwave pyramidal horn radiators with curvilinear generatrix  

British Library Electronic Table of Contents (United Kingdom)

Calculation method for pyramidal horn radiators (PHR) with curvilinear generatrix has been developed on the basis of the theory of waveguide tapers. This method makes it possible to reduce the value of spurious reflection coefficients and transformation of the principal wave into waves of higher order modes by forming generatrixes of walls with specific curvilinearity.

2008-01-01

420

Titanium Alloys for Medical Instrumentation  

International Science & Technology Center (ISTC)

The New Titanium Alloys With Increased Mechanical Properties and Corrosion Resistance for Medical Instruments and their Coatings

449

MICROMECHANICS - COMPRESSIVE PROPERTIES OF ...  

Science.gov (United States)

... slenderness ratio. Equations which determine the ultimate compressive strength of a composite were established. Several ...

1965-05-01

452

Inorganic chemistry of astatine  

International Nuclear Information System (INIS)

On the basis of experimental and extrapolated values the physico-chemical properties of astatine are reviewed considering all oxidation states.

455

Ideal gas of tachyons  

Energy Technology Data Exchange (ETDEWEB)

In this paper we consider properties of the ideal gas of classical (nonquantum) tachyons.

1983-10-15

459

Electrodepositing Nanostructured Composite Coatings  

International Science & Technology Center (ISTC)

Development of the Method of Electrodepositing Nanostructured Composite Coatings with Improved Engineering Properties

470

Boron-10 Materials Production  

International Science & Technology Center (ISTC)

Development of Technologies for Boron-10 Isotope Modified Boron-containing Materials Production and their Properties Investigation.

478

Database for thermal and mechanical properties of REBaCuO bulks  

International Nuclear Information System (INIS)

The thermal properties (thermal conductivity, thermal diffusivity, thermoelectric power, thermal dilatation, etc.) and the mechanical properties (Young's modulus, strength, hardness, fracture toughness, etc.) have been measured at low temperatures (4-300K) and under a high magnetic field (0-10T) for about 50 REBaCuO bulks (RE=Y, Gd, Nd, Sm, Dy, etc.). We have constructed the database of these properties and opened it on the Web site (thermal properties: http://ikebehp.mat.iwate-u.ac.jp/database.html and mechanical properties: http://paris.mech.iwate-u.ac.jp/sc-bulk/database.html). The influence of the species of RE ions, the content, size and dispersion of the RE211 (or Nd422) phase and Ag particles and the defects distribution on these properties is characterized.

2005-10-01

479

Optical properties of proton-irradiated polymers  

Energy Technology Data Exchange (ETDEWEB)

Recently, organic semiconducting materials have gained a broad interest due to their potential for organic electronic devices such as organic light emitting diode (OLED), organic photovoltaic devices and organic field-effect transistors (OFETs). Optical properties of organic semiconducting materials are important for practical application. For example, the power conversion efficiency of organic photovoltaic devices is mainly affected by absorption properties of organic materials. Proton irradiation is one of the efficient methods to change the optical properties of organic materials. In this paper, we investigate the changes of optical properties of various polymers using the proton irradiation.

2009-05-15

480

Methodological Quality of Studies on the Measurement Properties of Neck Pain and Disability Questionnaires: A Systematic Review  

British Library Electronic Table of Contents (United Kingdom)

Objective: The aim of this study was to obtain an overview of the methodological quality of studies on the measurement properties of neck pain and disability questionnaires and to describe how well various aspects of the design and statistical analyses of studies on measurement properties are performed. Methods: A systematic review was performed of published studies on the measurement properties of neck pain and disability questionnaires. Two reviewers independently rated the quality of the studies using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. This checklist was developed in an international Delphi consensus study. Results: A total of 47 articles were included on the measurement properties of 8 different questionnaires. The meth...

2011-01-01

481

Understanding Groups' Properties as a Means of Improving Collaborative Search Systems  

CERN Document Server

Understanding the similar properties of people involved in group search sessions has the potential to significantly improve collaborative search systems; such systems could be enhanced by information retrieval algorithms and user interface modifications that take advantage of important properties, for example by re-ordering search results using information from group members' combined user profiles. Understanding what makes group members similar can also assist with the identification of groups, which can be valuable for connecting users with others with whom they might undertake a collaborative search. In this workshop paper, we describe our current research efforts towards studying the properties of a variety of group types. We discuss properties of groups that may be relevant to designers of collaborative search systems, and propose ways in which understanding such properties ...

2009-01-01

482

Ceramic Materials and Devices  

Science.gov (United States)

Course website from Cambridge on ceramic materials. This site contains eight lectures in PDF format (Adobe Reader required), two question sheets, five practicals (including answers), digital movies and further useful links. "There is a strong relationship between the structure of a material and its physical properties. The properties of a material whether mechanical, electrical, optical or magnetic, determine how it can be used in practical applications. In this course, the focus is on the structure / property relationship for ionic materials with electrical properties utilised in various transducer devices. The materials considered include perovskites, which have special polarisation properties exploited in ferroelectric, pyroelectric and piezoelectric devices. Other oxides, such as zirconia, have structures permitting rapid diffusion of ions, making them suitable for use in ...

2007-02-01

483

Vessel wall MRI of the thoracic aorta: correlation to histology and transesophageal ultrasound. Preliminary results  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To visualise the vessel wall of the descending thoracic aorta using magnetic resonance imaging. To evaluate the diagnostic potential of tailored T{sub 1}-weighted sequences with contrast enhancement to assess systemic atherosclerotic disease. Methods: This study was performed on a clinical 1.5 Tesla scanner using a gradient strength of 30 mT/m and the phased array spine coil. A cadaver was examined to optimise a magnetic resonance imaging (MRI) protocol to evaluate atherosclerotic aortic wall disease. The acquired MR images were compared to gross specimens and histology. Subsequently seven patients who had undergone transesophageal ultrasound (TEU) with detailed assessment of the descending thoracic aorta were examined with MRI. The optimised protocol included untriggered and fat suppressed T{sub 2}-weighted turbo spin echo sequences and ECG-triggered and fat suppressed T{sub 1}-weighted spin echo sequences before and after iv administration of Gd-DTPA. ...

2002-05-01

484

MRI-based N-staging in esophageal cancer; N-Staging des Oesophaguskarzinoms mittels MRT unter Verwendung von artefaktreduzierenden LOTA-Sequenzen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by ...

2002-10-01

485

Molybdenum. Suppl. Vol. A 2a. Element. Physical properties. Pt. 1. 8. Rev. Ed  

Energy Technology Data Exchange (ETDEWEB)

The major part of the chapter 'Physical Properties' in concerned with, in addition to nuclear and atomic properties, the properties of the metal molybdenum. Due to the huge number of relevant papers, the present volume comprises only the first part of the metal properties, i.e. the crystallographic properties, the electronic structure, the lattice dynamics, and subsequently the mechanical and thermal properties. There are two small sections where the properties of the molecules, primarily Mo/sub 2/ and Mo/sub 6/, and of the vapor are described. The strength and some other mechanical properties have been frequently investigated to establish the change due to neutron irradiation, because this affects the durability of the fuel containers in nuclear reactors. For that purpose, changes in structure, ...

1985-01-01

486

The role of interventional radiology in management of patients with end-stage renal disease  

Energy Technology Data Exchange (ETDEWEB)

The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. The ...

2003-05-01

487

MR imaging guidance and monitoring of focal thermotherapies. A review; Steuerung und Monitoring von fokalen Thermotherapien mit der Magnetresonanztomographie. Ein Ueberblick  

Energy Technology Data Exchange (ETDEWEB)

Minimally invasive thermotherapies for focal tissue destruction on the basis of laser-, microwave-, focused ultrasound-, or cryogeninduced changes of tissue temperature represent an alternative to surgical tissue ablation, particularly in the treatment of tumors. The thermotherapy modalities listed necessitate indirect guidance and monitoring, since they often do not lend themselves to immediate visual control. In the brain, in head and neck tumors, in the liver, and in the prostate, MRI reliably and accurately delineates both the positions of interstitial thermotherapy applicators and - in contrast-enhanced, T1-weighted images - the perfusion defects in tissue necrosis induced by thermotherapy. The transfer of results of in-vitro and in-vivo model studies to assess interstitial temperature and lesion development during thermotherapy to the actual treatment of patients, however, is still in an initial phase. Further development of both rapid MRI sequences and MRI ...

1998-03-01

488

Time-resolved reflectance studies of silicon during laser thermal processing of amorphous silicon gates on ultrathin gate oxides  

International Nuclear Information System (INIS)

In this paper, we report the systematic investigation on the melt characteristics of silicon during laser thermal processing (LTP) of amorphous silicon (a-Si) gates on ultrathin gate oxides. LTP is used to reduce the gate depletion effect in advanced semiconductor devices. The influence of implantation-induced damage and chemical inhomogeneities on the melt behavior of ion-implanted a-Si is studied using in situ time-resolved reflectance (TRR) measurements and ex situ secondary ion mass spectrometry. The results from TRR measurements indicate the presence of a buried melt for a-Si implanted with B"+ at a subamorphizing dose. In contrast, such a melt behavior is not observed during LTP of undoped a-Si and a-Si implanted with As"+ at an amorphizing dose. We attribute the marked difference in the melt characteristics to the competitive effects between compositional inhomogeneities and the extent of amorphization in the a-Si layer. It should be noted that the ...

2004-06-01

489

Proton magnetic resonance spectroscopy reflects cellular proliferative activity in astrocytomas  

International Nuclear Information System (INIS)

We examined whether proton magnetic resonance spectroscopy (MRS) could provide accurate information on histological grade and cell proliferation in astrocytomas. We studied 23 patients with astrocytomas: five grade II, 10 grade III and eight with grade IV (glioblastoma multiforme). We performed proton MRS and determined the Ki-67 labeling index (LI), a tumour proliferation marker, in the same areas of the astrocytomas, and examined the statistical relationship between proton MRS and Ki-67 LI. The N-acetylaspartate (NAA)/creatine-phosphocreatine (Cr) and NAA/choline (Cho)-containing compound ratios were always significantly lower and the Cho/Cr ratios significantly higher than those for normal brain. The Cho/Cr ratio correlated positively and the NAA/Cho ratio inversely with Ki-67 LI. These findings suggest that the Cho signal in proton MRS reflects cellular proliferation. In Kaplan-Meier survival analysis, there was no significant difference between high (> 2.0, ...

2000-05-01

490

Possible two-gap superconductivity in NdFeAsO{sub 0.9}F{sub 0.1} probed by point-contact Andreev-reflection spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Systematic studies of the NdFeAsOF superconducting energy gap using point-contact Andreev-reflection (PCAR) spectroscopy are presented. At low temperatures the PCAR conductance spectra show a pair of gap-like peaks at about {+-} (4-7) mV and in most cases also a pair of humps at around {+-} 10 mV. Fits to the s-wave two-gap model of the PCAR conductance allowed to determine two superconducting energy gaps in the system. However, the energy-gap features disappear at T* = 15-20 K, much below the particular T{sub c} of the junction under study. At T* a zero-bias conductance (ZBC) peak emerges, which at higher temperatures usually overwhelms the spectrum with an intensity significantly higher than the conductance signal at lower temperatures. Possible causes of this unexpected temperature effect are discussed. In some cases the conductance spectra show just a reduced conductance around the zero-bias voltage, the effect persisting well above the bulk transition ...

2009-01-15

491

Polarization of electron cyclotron emission spectra in LHD  

Energy Technology Data Exchange (ETDEWEB)

Electron cyclotron emission (ECE) can be used to determine the electron temperature profile in magnetized plasmas. The complex structure of the magnetic field configuration in the Large Helical Device (LHD), which has a large shear, complicates the analysis of the ECE spectrum. In a sheared magnetic field the propagation of X and O-mode polarization through the plasma are coupled, causing mode conversion and polarization rotation. Mode scrambling is also caused by wall reflections. In this report, this mode conversion in LHD is numerically analyzed. It was found that at low density mode conversion scrambles the ECE spectra. However, at higher density (n{sub eo} > 1.0{center_dot}10{sup 19} m{sup -3}) the polarization mode is found to rotate with the sheared magnetic field, yielding only a negligible mode conversion. Wall reflections are found to depolarize the ECE spectrum. Notwithstanding the LHD magnetic configuration, it is shown that ...

1999-07-01

492

Optoelectronic multipoint liquid level sensor for light petrochemical products  

Science.gov (United States)

In this article we describe an optoelectronic sensor for assessing the level of light petrochemical products in technological tanks at the oil refineries. This sensor employs the multi-element vertical array of discrete micro- optical refractometric transducers. The transducers are made of silica glass and have the conical shape. In the air, each transducer operates as a tiny retro-reflector that optically couple together two multimode optical fibers. The optical coupling in the transducer is due to the internal reflection at the conical surface. The amount of the coupling depends on the refractive index of the surrounding media. In a fluid, the total internal reflection vanishes and the coupling becomes negligibly small. The number of immersed transducers is a measure of the fluid level in the reservoir. Because of the significance of the transducer transmission function, it is evaluated in detail under various combinations of the geometrical ...

2000-06-01

493

ORNL long-range environmental and waste management plan  

Energy Technology Data Exchange (ETDEWEB)

This report, the ORNL Long-Range Environmental and Waste Management Plan, is the annual update in a series begun in fiscal year 1985. Its primary purpose is to provide a thorough and systematic planning document to reflect the continuing process of site assessment, strategy development, and planning for the current and long-term control of environmental issues, waste management practices, and remedial action requirements. The document also provides an estimate of the resources required to implement the current plan. This document is not intended to be a budget document; it is, however, intended to provide guidance to both Martin Marietta Energy Systems, Inc., and the US Department of Energy (DOE) management as to the near order of magnitude of the resources (primarily funding requirements) and the time frame required to execute the strategy in the present revision of the plan. As with any document of this nature, the near-term (one to three years) part of the plan ...

1989-09-01

494

Measuring characteristics on emissivity using infrared thermometer for RCCS  

International Nuclear Information System (INIS)

In VHTGR (Very High Temperature Gas-cooled Reactor), the radiation plays an important role in heat transfer through the cavity in RCCS (Reactor Cavity Cooling System). We performed the series of experiments to measure the emissivity using the infrared thermometer with wavelength range of 8#approx#14 #mu#m. As the first step, the transmittance of Zinc Selenide (ZnSe) window was measured to estimate the emissivity that can compensate the attenuation effect of window. The kind of gas with various concentrations in the cavity will be released during postulated accidents to the coolant type, so it is essential to estimate the effects of gas on the measurement of emissivity. In this manner we measured the emissivity with the air, the helium and the steam inside chamber. The results represent that the concentration of the air and the helium do not affect the emissivity significantly while the steam decreases the measured emissivity relatively. It means that the air and the helium do not ...

2004-12-01

495

Magnified x-ray phase imaging using asymmetric Bragg reflection: Experiment and theory  

International Nuclear Information System (INIS)

X-ray imaging using asymmetric Bragg reflection in the hard x-ray regime opens the way to improve the spatial resolution limit below 1 #mu#m by magnifying the image before detection, simultaneously providing a strong phase contrast. A theoretical formalism of the imaging process is established. Based on this algorithm, numerical simulations are performed and demonstrate that both Fresnel propagation and Bragg diffraction contribute to contrast formation. The achievable resolution of this technique is investigated theoretically; the results obtained can be used to improve future experimental setups. Furthermore, the minimum detectable phase gradient is estimated, for comparison with other phase sensitive imaging techniques. Results from biological objects demonstrate that the technique is viable for imaging both in two and three dimensions. Refraction contrast images are extracted from experimental projection images by an algorithm similar to diffraction-enhanced ...

2006-08-01

496

Impact of climate change on carbon cycle in freshwater ecosystems  

Energy Technology Data Exchange (ETDEWEB)

The impacts of the expected climate change on Finnish lake ecosystems were studied with the biota of the mesohumic Lake Paeaejaervi, southern Finland. Experimental conditions, from small-scale experiments on single species level to a large-scale ecosystem manipulation, were established to simulate directly the future climate and/or loading of nutrients and dissolved organic matter (DOM) from the drainage area. The experimental studies were accomplished by modelling the carbon flow in the pelagic food web as well as the growth of littoral macrophytes. The main hypothese tested were as follows: As a consequence of the climate change (rising temperature and increasing precipitation) the loading of nutrients and dissolved organic matter (DOM) from the drainage area to the lake will increase. In the pelagic zone this will be first reflected i higher productivity of primary producers and bacteria, but will later affect the entire food chain. Increase in atmospheric ...

1996-12-31

497

Determination of trace elements in Syrian medicinal plants and their infusions by energy dispersive X-ray fluorescence and total reflection X-ray fluorescence spectrometry  

Energy Technology Data Exchange (ETDEWEB)

X-ray fluorescence (XRF) and total-reflection X-ray fluorescence (TXRF) techniques suited well for a multi-element determination of K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr in some Syrian medicinal plant species. The accuracy and the precision of both techniques were verified by analyzing the Standard Reference Materials (SRM) peach-1547 and apple leaves-1515. A good agreement between the measured concentrations of the previously mentioned elements and the certified values were obtained with errors less than 10.7% for TXRF and 15.8% for XRF. The determination of Br was acceptable only by XRF with an error less than 24%. Furthermore, the XRF method showed a very good applicability for the determination of K, Ca, Mn, Fe, Cu, Zn, Rb, Sr, and Br in infusions of different Syrian medicinal plant species, namely anise (Anisum vulgare), licorice root (Glycyrrhiza glabra), and white wormwood (Artemisia herba-alba)

2009-07-15