WorldWideScience
1

ASE FILE  

Science.gov (United States)

radionuclide X-ray fluorescence analysis: the resolving power of the ... The radiation detectors used in radionuclide X-ray fluorescence ...

2

Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation  

Science.gov (United States)

This investigation describes the technique for the detection of the X-ray fluorescent radiation

1972-01-01

3

Radionuclide X-ray fluorescence analysis. 1: Excitation of X-ray fluorescense radiation by nuclear radiation  

Science.gov (United States)

The principles of radionuclide excitation of X-ray fluorescence radiation and its application in

1972-01-01

4

Radionuclide X-ray fluorescence analysis. 3: Examples of application in practice  

Science.gov (United States)

Examples are given of the applicability and importance of radionuclide fluorescence analysis as a

1973-01-01

5

Radionuclide X-ray fluorescence analysis of solid aerosol particles on Synpor 4 collection filters  

International Nuclear Information System (INIS)

The feasibility was studied of the application of radionuclide X-ray fluorescence analysis to the identification and determination of chemical elements in the air. A description of the method is presented, the main stages of the analysis are discussed (sample preparation and standards, selection of radioactive radiation sources, geometry of measurement and evaluation of results). The method is illustrated on the determination of elements Fe, Cu, Zn, Br, and Pb in air samples taken in the city of Prague. (author) 2 tabs., 2 figs., 14 refs.

1992-01-01

6

7. Overview of radionuclide X-ray fluorescence analysis of components of the environment  

International Nuclear Information System (INIS)

A survey is presented of studies dealing with radionuclide X-ray fluorescence analysis (RXFA) of impurities in the air, water, soil, sediments and biological materials, mainly blood, urine, hair, soft tissues and bones. Tabulated are lists of published works on RXFA of the air, water and biological materials. (ES).

1983-12-01

7

Inner-shell excitation of intrinsic luminescence and resonantly excited X-ray fluorescence at Be 1s edge in oriented BeO crystals  

International Nuclear Information System (INIS)

The results of studies of the time-resolved luminescence of self-trapped excitons (STE) with different multiplicity as well as the X-ray emission in oriented BeO crystals under excitation in the vicinity of the 1 s Be photoabsorption edge are presented. The branching of the electronic excitations relaxation depends strongly on the crystal orientation after the inner-shell excitation. The common features between the processes of the STE luminescence and resonantly excited X-ray fluorescence have been discussed.

2007-05-21

8

X-Ray Fluorescence Analysis of Composite Propellants for ...  

Science.gov (United States)

... The constancy of the X-ray intensity ratio for each element in Table 8 as the X-ray tube settings were changed shows the excellent compensating ...

1977-06-03

9

The fluorescence properties and NMR analysis of protopine and allocryptopine  

International Nuclear Information System (INIS)

The fluorescence properties of protopine and allocryptopine in aqueous and organic environments are described for the first time. The fluorescence of alkaloids and their pH-dependent interconversion to cationic forms (transannular interaction) were studied using steady-state and time-resolved fluorescence techniques. For the analysis of tricyclic base and cis/trans tetracyclic cations of the alkaloids, NMR and X-ray crystallography were used. - Highlights: ? We describe fundamental fluorescence characteristics of alkaloids protopine and allocryptopine. ? We analyzed the pH-dependent transitions and cis/trans isomerization. ? These two alkaloids can be better distinguished by their fluorescence decay characteristics. ? The fluorescence parameters are related to the NMR and crystallographic structural data.

2011-07-01

10

x - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011 ... Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation ...

11

NASA Technical Reports Server - Radionuclide X-ray fluorescence ...  

Science.gov (United States)

Aug 1, 1972 ... The principles of radionuclide excitation of X-ray fluorescence radiation and its application in analytic chemistry are discussed.

12

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

British Library Electronic Table of Contents (United Kingdom)

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

2010-01-01

13

Influence of alloying effect on X-ray fluorescence parameters of Co and Cu in CoCuAg alloy films  

British Library Electronic Table of Contents (United Kingdom)

In this study, Kb/Ka X-ray intensity ratios, Formula Not Shown , Formula Not Shown production cross-sections and K fluorescence yields of Co and Cu and Lb/La X-ray intensity ratios, Formula Not Shown , Formula Not Shown production cross-sections and Formula Not Shown average fluorescence yields of Ag in pure metals and in different alloy compositions were measured. In this study, alloying effects on the Formula Not Shown production cross-sections of Co and Cu were investigated and changes interpreted according to the rearrangement of valance state electrons and the charge transfer process between the 3d elements (Co and Cu) and Ag.

2009-01-01

16

Radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Slovak 1973. 164 p. Czechoslovakia Havranek, E. Bumbalova, A. Svitel,

1973-01-01

17

NONDESTRUCTIVE DETERMINATION OF AIRBORNE LEAD ...  

Science.gov (United States)

... NONDESTRUCTIVE DETERMINATION OF AIRBORNE LEAD PARTICULATES BY THE RADIONUCLIDE X-RAY FLUORESCENCE ANALYSIS. ...

20

Determination of heptacaine hydrochloride in solution using nuclear analytical methods  

Energy Technology Data Exchange (ETDEWEB)

The applicability of two nuclear analytical methods: radionuclide X-ray fluorescence analysis and radiometric titrations based on precipitate formations was studied in order to determine the heptacaine hydrochloride in solutions. The applied methods were evaluated based on the obtained sensitivity values.

1984-01-20

21

Determination of heptacaine hydrochloride in solution using nuclear analytical methods  

International Nuclear Information System (INIS)

The applicability of two nuclear analytical methods: radionuclide X-ray fluorescence analysis and radiometric titrations based on precipitate formations was studied in order to determine the heptacaine hydrochloride in solutions. The applied methods were evaluated based on the obtained sensitivity values. (author).

1984-01-01

22

Radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The author's achievements in the title field are summarized and discussed. The following topics are dealt with: (i) principles of radionuclide X-ray fluorescence analysis; (ii) mathematical methods in X-ray fluorescence analysis; (iii) Ross differential filters; (iv) application of radionuclide X-ray fluorescence analysis in the coal industry (with emphasis on the determination of the ash content, sulfur content, and arsenic content of coal); and (v) evaluation of the X-ray fluorescence analyzer from the radiological safety point of view. (P.A.).

1994-01-01

23

Use of X-ray fluorescence analysis in the study of archeological samples  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis (XFA) was used in the determination of the contents of metal residues in dosing plates for coin minting. XFA was also used for the determination of the strontium/calcium ratio in bone samples of different animals with the aim to obtain information on the food composition of these animals. It was found that bones of different animals can be distinguished based on the Sr/Ca ratio. No significant differences in the Sr/Ca ratio were observed in human bones of individuals from different social groups. (author). 1 fig., 5 tabs., 4 refs.

1988-09-26

24

Determination of concentration distribution of admixtures by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

A theoretical analysis is presented for the method of determining the concentration distribution of admixtures in zone melting and in the study of diffusion in melts. Continuous mode X-ray fluorescence analysis is considered. The convolution integral interpreting the analog output of the ratemeter was solved applying the mathematical apparatus of Z transformation. The feasibility of the method is tested on an example of the determination of tin distribution in tungsten. With respect to the statistical error (#delta#<1.5%), the maximum integration constant (100 s) and a very slow sample feed (0.025 mm/s) were used. The calculated transfer function reflects the total transfer function of the ratemeter and the recorder used. (M.D.).

1985-01-01

25

Determination of Mn, Fe, Cu, Zn, and Pb in particulate matter, raw and final materials of a brick factory by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and "2"3"8Pu exciting source was used in the study of Mn, Fe, Cu, Zn, and Pb content of solid emissions, raw and final materials of a brick factory. From the point of view of metal content, the working environment if the brick factory is safe for workers. (author) 2 refs.; 2 figs.; 1 tab.

1994-01-01

26

Resonant inelastic soft x-ray scattering of CdS: a two-dimensional electronic structure map approach  

Energy Technology Data Exchange (ETDEWEB)

Resonant inelastic x-ray scattering (RIXS) with soft x-rays is uniquely suited to study the elec-tronic structure of a variety of materials, but is currently limited by low (fluorescence yield) count rates. This limitation is overcome with a new high-transmission spectrometer that allows to measure soft x-ray RIXS"maps." The S L2,3 RIXS map of CdS is discussed and compared with density functional calculations. The map allows the extraction of decay channel-specific"absorp-tion spectra," giving detailed insight into the wave functions of occupied and unoccupied elec-tronic states.

2008-09-24

27

Determination of ash content in coal by means of backscattered X-ray radiation and X-ray fluorescence analysis, and devices manufactured by the PAR company  

Energy Technology Data Exchange (ETDEWEB)

Discusses methods for determining ash content in coal using backscattering in X-ray fluorescence. The following aspects are evaluated: principle of ash content determination, energy sources, factors that influence measurement accuracy, reliability. Types of X-ray fluorescence analyzers developed in Czechoslovakia and manufactured in the Czech Republic are comparatively evaluated. Operation of the RPM 113.1 radionuclide X-ray fluorescence analyzer developed by the PAR company and used for measuring ash content in coal and coal calorific value is discussed. 7 refs.

1993-09-01

28

Radionuclide X-ray fluorescence analysis of waste water from the production of citric acid  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid.

1982-02-18

29

Radionuclide X-ray fluorescence analysis of waste water from the production of citric acid  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid. (author).

1982-02-01

30

Contribution to the radionuclide x-ray fluorescence analysis of human blood and plasma  

International Nuclear Information System (INIS)

A photon-induced x-ray fluorescence method allowing the simultaneous determination of iron, copper, zinc, bromine and rubidium in human blood and blood plasma samples is described. The method is reliable and has a good sensitivity for a wide range of elements. (author).

1986-04-01

31

8. Application of radionuclide X-ray fluorescence analysis in other fields of science and technology  

International Nuclear Information System (INIS)

Certain applications are described of radionuclide X-ray fluorescence analysis in the ore dressing industry, in the manufacture of building materials, in metallurgy, pharmacy, in the chemical, photographic and paper industries, in space exploration, in archeology and for measuring the thicknesses of thin layers of coatings. (ES).

1983-12-01

32

Radionuclide X-ray fluorescence analysis using semiconductor detectors  

International Nuclear Information System (INIS)

Czech May 1979. p. 32-33. Czechoslovakia Benada, J. Spacek, B. Ustav

1979-05-01

33
34

Microcomputers in radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Czech Apr 1986. p. 51. Czechoslovakia Cechak, T. Kluson, J. Ceske

1986-04-01

35

Characterisation and use of biomass fly ash in cement-based materials  

British Library Electronic Table of Contents (United Kingdom)

This paper presents results about the characterisation of the biomass fly ashes sourced from a thermal power plant and from a co-generation power plant located in Portugal, and the study of new cement formulations incorporated with the biomass fly ashes. The study includes a comparative analysis of the phase formation, setting and mechanical behaviour of the new cement-fly ash formulations based on these biomass fly ashes. Techniques such as X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), thermal gravimetric and differential thermal analysis (TG/DTA), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and environmental scanning electron spectroscopy (ESEM) were used to determine the structure and composition of the formulations. Fly ash F1 from the t...

2009-01-01

37

Radionuclide X-ray fluorescence analysis of components of the environment  

International Nuclear Information System (INIS)

The physical foundations and methodology are described of radionuclide X-ray fluorescence analysis. The sources are listed of air, water and soil pollution, and the transfer of impurities into biological materials is described. A detailed description is presented of the sampling of air, soil and biological materials and their preparation for analysis. Greatest attention is devoted to radionuclide X-ray fluorescence analysis of the components of the environment. (ES).

1983-01-01

38

Present state of radionuclide X-ray fluorescence analysis in coal mining  

International Nuclear Information System (INIS)

Applications of X-ray fluorescence analysis in coal mining and geology are briefly described based on results published in Czechoslovakia as well as abroad over the past 3 years. Particular attention is paid to the rapid determination of the ash content of coal using portable radionuclide X-ray fluorescence analyzers that are being developed in Czechoslovakia. (author).

1990-01-01

39

Contribution to the in vitro multielement X-ray fluorescence analysis of human soft tissues  

International Nuclear Information System (INIS)

Determination of Mn, Fe, Ni, Cu, Zn, and Pb in human soft tissues by radionuclide X-ray fluorescence analysis (using "2"3"8Pu and "1"0"9Cd sources) is described. The results of multielement XRS analysis of selected human tissues are tabulated. They are in good agreement with the literature data. It is concluded that X-ray fluorescence technique is a suitable method for trace element determination. (author).

1986-11-01

40

Analytic description of X-ray fluorescence intensity as a function of the particle size in powder samples and pulp upon X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Analytic expression is derived for X-ray fluorescence dependence on the particle size of powder and slurry media. The expression is obtained for a model of powder medium containing particles of different size and random distribution in the bulk of the sample. Limiting cases of homogeneous and slurry-like media are considered and expressions for calculation of the fluorescence intensity are derived. The results reasonably match the experiment for binary powder mixtures and thus provide evaluation of the powder particle size on the fluorescence intensity for multicomponent polydisperse powder medium

2007-11-01

41

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

International Nuclear Information System (INIS)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows timeadvantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore"T"M and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most effective sorption of determined elements are also interpreted. (author)

2008-03-01

42

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

British Library Electronic Table of Contents (United Kingdom)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows time-advantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore? and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most ef...

2008-01-01

43

Nondestructive determination of airborne lead particulates by the radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Airborne lead particulates collected on a membrane filter were determined by the nondestructive X-ray fluorescence method. The gamma/X radionuclide source "2"4"1Am/Ag and a scintillation detector with a NaI/Tl crystal were used for the excitation and detection, respectively, of L X-rays of Pb. One can say, with reference to the obtained results, that the sensitivity and accuracy of the measurement is more than adequate for monitoring the Pb level in air. (author).

1980-01-01

44

Determination of ash in coal by X-ray backscattering and X-ray fluorescence analysis and apparatus by the PAR company  

International Nuclear Information System (INIS)

The basic principles of determination of the ash content of coal by the title methods are outlined. A brief technical characteristic of the ash meters and radionuclide X-ray fluorescence analyzers manufactured by the PAR company is presented. (Z.S.). 4 figs., 7 refs.

1993-01-01

45

3. Physical foundations and methodology of radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The physical foundations are described of radionuclide X-ray fluorescence analysis (RXFA) and the table shows the values of K- and L-absorption thresholds and the K- and L-line energies of elements. The calculation of the intensity of characteristic radiation during RXFA proceeds from relations derived for conventional X-ray fluorescence analysis. The choice of the radionuclide source is ruled by the nature of the analysed substance and the used detection technique. The diagram shows the areas of radionuclide sources and the energy of the fluorescence radiation of elements. The table shows the spectra of radionuclide sources suitable for the purposes of RXFA measured by semiconductor Si(Li) and Ge(Li) detectors. (ES).

1983-12-01

46

Contribution to the sample preparation in the radionuclide X-ray fluorescence analysis of hair  

International Nuclear Information System (INIS)

Methods of sample treatment in XRF analysis of hair are studied in view of the effect on analytical results. A new method is proposed based on the incomplete ashing of hair followed by pellet preparation. Its suitability is estimated on the XRF analysis of real hair samples collected from 4 healthy adults. (author) 12 refs.; 4 figs.; 1 tab.

1989-03-01

47

Valence electronic structure of Ni in Ni-Si alloys from relative K X-ray intensity studies  

Energy Technology Data Exchange (ETDEWEB)

The K{beta}-to-K{alpha} X-ray intensity ratio of Ni in Ni{sub 3}Si, Ni{sub 2}Si and NiSi has been determined by energy dispersive X-ray fluorescence technique. It is found that the intensity ratio of Ni decreases from pure Ni to Ni{sub 2}Si and then increases from Ni{sub 2}Si to NiSi, in good agreement with the electronic structure calculations cited in the literature. We have also performed band structure calculations for pure Ni in various atomic configurations by means of linear muffin-tin orbital method and used this data with the normalized theoretical intensity ratios cited in the literature to estimate the 3d-occupation numbers of Ni in Ni-Si alloys. It is emphasized that investigation of alloying effect in terms of X-ray intensity ratios should be carried out for the stoichiometric alloys in order to make reliable and quantitative comparisons between theory and experiment in transition metal ...

2007-02-15

48

Alloying effect on K to L shell vacancy transfer probabilities in 3d transition metals  

British Library Electronic Table of Contents (United Kingdom)

The alloying effects on K to L shell vacancy transfer probabilities (?KL) in 3d transition metals have been carried out by X-ray fluorescence studies of various alloy compositions. K X-ray intensity ratios of Ti, Cr, Fe, Co, Ni, and Cu elements in the FexNi1?x, FexCr1?x, NixCr1?x, FexCryNi1?(x+y), TixNi1?x, TixCo1?x, and CoxCu1?x alloys have been measured following excitation by 22.69keV X-rays from a 10 mCi 109Cd radioactive point source and ?KL values for alloying elements have been determined from these ratios. The spectrum of characteristic K-X-ray photons from samples were detected with a high resolution Si(Li) detector coupled to a 4 K multichannel analyzer. The present investigation makes it possible to ...

2010-01-01

49

An Apparent Hard X-ray Decline of CH Cygni  

CERN Document Server

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

2006-01-01

50

Radionuclide X-ray fluorescence determination of Mn, Fe, Cu, Zn and Pb in wastewaters and sludges from wastewater treatment plants in Bratislava (SR)  

International Nuclear Information System (INIS)

Radiometric X-ray fluorescence analysis was used for the determination of Mn, Fe, Cu, Zn and Pb in wastewater and sludges from three wastewater treatment plants in Bratislava (SR). Metals were determined in wastewaters after preconcentration by 8-hydroxyquinoline and in sludges by drying and pressing to pellets. "2"3"8Pu and "1"0"9Cd was used for excitation of fluorescence radiation. (author).

1997-01-01

51

Phase imaging using laser-produced X-ray sources  

International Nuclear Information System (INIS)

A possible novel application of hard x-ray emitted during laser-plasma interaction was discussed. The authors established an Optical Transform Function to study the joint effect of the spectral distribution and temporal profile of the laser-produced x-ray on x-ray phase imaging. Though the laser-produced x-ray pulse duration is short and incoherent, the analysis confirms that the current x-ray phase imaging theory still holds for laser-produced x-ray phase imaging

2000-08-01

52

X-ray fluorescence analysis as auxiliary method of restorers  

International Nuclear Information System (INIS)

The principle is described of X-ray fluorescence analysis and the manner of detecting the emitted characteristic radiation. The advantages are presented of radionuclide X-ray fluorescence analysis which consist primarily in the possibility of conducting a totally non-destructive analysis, and of accurate and relatively narrow localization of the analyzed area, the simultaneous qualitative and quantitative determinations of a large number of elements in the order of concentrations 10"1 to 10"-"4%, stability of excitation radiation flux, simple design and relatively low capital costs. The so-called matrix effect is pointed to. A number of examples is given of the use of the cited method, including its use in the analysis of art objects. (J.B.).

1987-09-07

56

PRICES SUBJECT To CHq.G - NASA Technical Report Server (NTRS)  

Science.gov (United States)

by the radionuclide X-ray fluorescence analysis into several groups according to the atomic number of the determined element. Table I documents this. ...

58

Analysis of the archaeological pieces with the PIXE technique; Analisis de piezas arqueologicas con la tecnica PIXE  

Energy Technology Data Exchange (ETDEWEB)

The handling of physical-nuclear techniques for the analysis of archaeological pieces it was carried out by first time in 1956 by the doctors Oppenheimer and Dodsom (in the United States); who wrote about the wide utilities of the neutron activation analysis (NAA), this technique requires of a nuclear reactor that could be considered like one a factory of thermal neutrons necessary to carry out this analysis. The first experiments in that were applied the NAA were on ceramic coming from the Mediterranean, in those that the relationships of the elements of sodium and manganese were determined to know their elementary composition and to identify the origin of their manufacture. Later on other study techniques were applied in archaeological materials, as the X-ray fluorescence, Moessbauer spectroscopy, scanning electron microscopy, PIXE analysis (particle induced x-ray emission), among other, this last is ...

2005-07-01

59

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-12-15

60

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

International Nuclear Information System (INIS)

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

2008-12-01

61

Position-sensitive proportional counter for space-based X-ray imaging studies  

International Nuclear Information System (INIS)

ASTROSAT, India's first dedicated astronomy satellite is slated for launch in 2007. The primary science objective of ASTROSAT is to explore the Universe using broad-band instruments covering optical, UV, soft X-ray and hard X-ray studies

2005-03-01

62

Beam-induced damage on diffractive hard X-ray optics  

UK PubMed Central (United Kingdom)

The issue of beam-induced damage on diffractive hard X-ray optics is addressed. For this purpose a systematic study on the radiation damage induced by a high-power X-ray beam is carried out in both...Full Text Available

2010-11-01

63

Coupling of Pressure-Induced Structural Shifts to Spectral Changes in a Yellow Fluorescent Protein  

UK PubMed Central (United Kingdom)

AbstractX-ray diffraction analysis of pressure-induced structural changes in the Aequorea yellow fluorescent protein Citrine reveals the structural basis for the continuous...Full Text Available

2009-09-16

64

A comparison of patient doses in lumbar spine radiography from various X-ray units in Poland  

Energy Technology Data Exchange (ETDEWEB)

A number of diagnostic X-ray units in Poland were subjected to analysis. The air kerma on X-ray tables was measured for the X-ray parameters used routinely during lumbo-sacral spine radiography of standard adult patient. Measurements of air kerma were performed using TLD made of lithium-fluoride. The doses received by patients in different X-ray departments can differ more than two orders of magnitude (from 0.42 mGy up to 72.11 mGy), for the same X-ray examination. The dose can be significantly reduced if fluorescent screens made from components of rare earth are used. (author). 10 refs, 1 fig., 2 tabs.

1995-12-31

65

Radionuclide X-ray fluorescence determination of Cr, Fe, Cu, Zn,and Pb in industrial wastewaters after preconcentration of determined elements  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of Cr, Fe, Cu, Zn and Ph in industrial wastewaters (from surface treatment of metals and glasses) after precipitation of determined elements by 8-hydroxyquinoline. (author).

1997-01-01

66

Heavy metals in industrial wastewater determined by radionuclide x-ray fluorescence analysis and their effects on Allium cepa root tip cells  

International Nuclear Information System (INIS)

Radionuclide x-ray fluorescence method was used in the determination of Cr, Ni and other heavy metals content in wastewater of an engineering plant taken both before and after chemical treatment. Toxic effects of the wastewaters using Allium cepa root tip cells were tested. (author) 8 refs.; 2 tabs.

1994-05-01

67

Heavy metals and some other elements in medicinal plants. Determined by X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Determination of Mn, Fe, Cu, Zn, Hg, Pb, Br, Se, Rb, Sr and Cd in the medicinal plants by radionuclide X-ray fluorescence analysis (using "2"3"8Pu, "2"4"1Am/Ag and "1"2"5I) is described. (author). 12 refs., 2 tabs.

1995-01-01

68

Heavy element contamination of surface waters in the region Banska Stiavnica (SR) measured by radionuclide X/ray fluorescence analysis  

International Nuclear Information System (INIS)

Heavy metals (Pb, Cd, Mn, Cu, Zn, Fe) were determined in surface waters in the surroundings of the depositories of the mining shrubs in the region of Banska Stiavnica (SR) by radionuclide X-ray fluorescence analysis. Allowed concentrations of the determined metals are exceeded numerously (multiplicity in some cases was 10"3-10"6). (author).

1997-01-01

69

Evaluation of adhesive plasters by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

A radiometric method was elaborated for surface density determinations of the adhesive layer of plasters by radionuclide X-ray fluorescence using the 17.47 keV bremsstrahlung of "1"4"7Pm/Mo. The bremsstrahlung line excites the 8.63 keV characteristic K#alpha# line of Zn contained in the adhesive layer of the plaster as a filling material in the form of ZnO. In homogeneous adhesive layers the Zn content is proportional to surface density. (author).

1976-01-01

70

Determination of cesium and selenium in cultivated mushrooms using radionuclide X-ray fluorescence technique  

International Nuclear Information System (INIS)

Cesium and selenium intake of cultivated mushrooms (Agaricus bisporus), with these elements previously added to culture medium, has been examined from the viewpoint of health- and environmental protection. The process of measuring has been carried out by the radionuclide X-ray fluorescence technique. Treatments of the elementary substance with Se salt appears to influence the Se content of the mushrooms to a significant extent. Cs intake is of considerable importance, as this element is accumulated by mushrooms. (author)

2000-09-01

71

Determination of Y, Ba and Cu in superconductor films by x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide x-ray fluorescence analysis was used for the determination of Y, Ba and Cu in thin high-temperature superconducting films. Atomic emission ICP spectrometry was used to estimate the precision and accuracy of analytical results. Reasonable agreement between both methods was obtained when a polynomial calibration curve was applied. (author) 4 refs.; 4 tabs.

1994-06-01

72

Determination of Mn, Fe, Ni, Cu, Zn and Pb contents in samples of apple trees by radionuclide X-ray fluorescence analysis  

Energy Technology Data Exchange (ETDEWEB)

The applicability of the radionuclide X-ray fluorescence analysis (RXFA) for qualitative and quantitative evaluation of environmental plant samples is discussed and examples of determination of Mn, Fe, Ni, Cu, Zn, Pb in samples of apple trees are given. The instrumentation, the standard and sample preparation are also presented.

1982-12-01

73

Determination of Fe and Zn in healing plants by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method was used for the determination of Fe and Zn in healing plants (Sage, Peppermint, Stinging, Common Agrimony, Milfoil, Ribwort, Tansy, White Dead-Nettle). "2"3"8Pu exciting source and Si/Li semiconductor detector were used for the determination. (author)

1999-06-01

74

Determination of Fe and Zn in agricultural plants with special cultivation by radionuclide x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Fe and Zn were determined in various parts of maize (Zea mays) in dependence on quantity of organic substrate EKOFERT as organic fertilizer in soil, using radionuclide X-ray fluorescence analysis. The increase of quantity of organic substrate EKOFERT in soil causes a decrease of heavy metal concentrations in certain parts of the plant. (author). 4 refs., 1 tab.

1996-01-01

75

Determination of Cu, Ni, Zn and Pb contents in taraxacum officinale near the highway D-61 Bratislava-Trnava (SR) by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and "2"3"8Pu exciting source was used for the determination of Cu, Ni, Zn and Pb in plant samples (Taraxacum officinale) from various localities near the highway D-61 Bratislava-Trnava (SR). (author) 2 refs.; 1 fig.; 1 tab.

1993-12-01

76

Determination of Cu, Ni, Zn and Pb contents in soil near the D-61 Bratislava-Trnava Highway by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and "2"3"8Pu exciting source was used for the determination of Cu, Ni, Pb, and Zn in soil samples from various localities near the D-61 Bratislava-Trnava highway (CSFR). (author) 1 ref.; 1 tab.

1993-01-01

77

Analysis of high-temperature superconducting films by x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of Cu, Y and Ba in very thin high-temperature superconducting films. The precision of the method is better than 3% for about 1 #mu#m thick films. The atomic emission ICP spectrometry was used to testify results of XRF analysis. An acceptable agreement of both methods was obtained. (author) 4 refs.; 2 tabs.

1991-09-01

78

Measurement of M shell X-ray production cross sections and fluorescence yields for the elements in the atomic range 70#<=#Z#<=#92 at 5.96 keV  

International Nuclear Information System (INIS)

Total M X-ray cross sections for 12 elements in atomic range 70#<=#Z#<=#92 were measured at 5.96 keV Mn K X-ray photon energy. The average M shell fluorescence yields (anti #omega#_M) of these elements have also been observed using the presently measured cross section values and the theoretical M shell photoionisation cross section values. (orig.).

79

A radionuclide analyzer of total sulfur in coal  

International Nuclear Information System (INIS)

The devised radionuclide analyzer for the determination of total sulfur in coal includes two radionuclide sources with different energies, which are accommodated in collimators fitted with adjustable diaphramgs. The sample compartment is located between the two sources. Moreover, an X-ray fluorescence standard can be slid into the sample compartment. A proportional detector for X-ray fluorescence and scattered gamma radiation is located off the sample compartment. The input of the proportional detector is interfaced to the output of a high-voltage supply, the output, to the information input of a control-and-evaluation unit. One of the control outputs of the control-and-evaluation unit is connected to the input of the sliding mechanism for the X-ray fluorescence standard. This arrangement enables automatic energy calibration of the analyzer. The analyzer can ...

1987-05-13

82

Determination of small amounts of elements by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The determination of small amounts of elements by radionuclide X-ray fluorescence analysis is described. Samples containing 5x10"-"4 to 5x10"-"6 g of elements were fixed on a suitable carrier. For a coaxial configuration a low-energy source of the #gamma#/X type was used, namely an annular "2"4"1Am/Ag source with an activity of 7.4x10"8 s"-"1 (20 mCi), and for a configuration with side reflection source of the #beta#/X type was used, namely "1"4"7Pm/Sm with the activity of Pm(OH)_3 approximately 3.7x1O"1"0 s"-"1 (1 Ci). Cs, Ba, La, Pr, Nd, and Ag were determined by means of the Ksub(#alpha#) line and Hg, W, Er, and Pr by means of the Lsub(#alpha#) line. For all elements studied a detection limit of the order of 10"-"7 g was achieved. (author).

1975-01-01

83

Measurement of K x-ray intensity ratio of tin, gadolinium and dysprosium  

International Nuclear Information System (INIS)

Full text: Measurement of K_#beta# to K_#alpha# x-ray intensity ratios are important not only in the field of atomic physics, radiation physics and medical physics, but also to test the validity of assumptions made in the theoretical prediction. The intensity ratios can also give information on the effect of physical and chemical environment of the element in the compound. Many investigators have adopted a single and double reflection geometries to measure the K_#beta# to K_#alpha# x ray intensity ratios to understand the effect of physical and chemical environment on x-ray fluorescence. The targets are excited by a radioactive source of having activity of the order 100 MBq. in order to carry out accurate measurement K_#beta# to K_#alpha# x-ray intensity ratios, we have develop 2#pi# geometrical configuration method : placing a target right on the surface of the ...

2003-11-01

84

Measurement of reactor tube cladding thickness by x-ray fluorescence spectrometry  

International Nuclear Information System (INIS)

An x-ray fluorescence spectrometer was designed and fabricated which nondestructively determines the thickness of aluminum cladding at small suspected thin spots in the inner or outer surface of actinide reactor tubes. The analysis method is based on the difference in absorption of actinide L/sub #alpha#/ and L/sub #beta#/ fluorescent x-rays in passing through the cladding. Calibration plots of the logarithm of the L/sub #beta#//L/sub #alpha#/ x-ray intensity ratio versus cladding thickness are linear to at least 40 mils for U-Al, U_3O_8-Al, and PuO_2-Al substrates. Accuracy and precision of the experimentally determined cladding thickness and evaluated for both uranium and plutonium substrates. Experimental thickness data are reported for 618 quality assurance analyses on six Mark 41 PuO_2-Al target tubes. An x-ray fluorescence cladding ...

1978-01-01

85

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

Energy Technology Data Exchange (ETDEWEB)

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

1983-01-01

86

Optimization of X-ray energy resolution from a horizontally focused single-crystal monochromator  

Energy Technology Data Exchange (ETDEWEB)

A method has been developed to optimize the energy resolution of a horizontally focusing monochromator. The method consists of determining the optimum radius of curvature of the cylindrically bent monochromator crystal by minimizing the total diffracted X-ray flux measured through an X-ray absorption foil. When measured at an absorption edge a global minimum can be identified, which corresponds to the minimum energy band accepted along the entire length of the crystal. Experimental verification of this method has been validated by comparing X-ray fluorescent scans taken for a series of crystal curvatures and by directly measuring the X-ray beam profiles at the corresponding points. The actual optical configuration and asymmetric-cut parameter of the focusing monochromator on beamline X4C at the National Synchrotron Light Source are modeled and ray tracing simulations of the optical ...

2009-02-11

87

X-ray micro-spectroscopy: a tool for micro-scale radionuclide speciation in heterogeneous nuclear waste repository materials  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Large-scale problems such as nuclear waste disposal are increasingly recognized to be interconnected to small scale-mechanisms. Thus, synchrotron-based high-resolution analytical X-ray probes become important tools for exploring the micro-scale chemical reactivity of heterogeneous barrier materials used in nuclear waste repositories. In this study the layout of the micro-XAS beamline at the Swiss Light Source (SLS) will be presented. The beamline is optimized towards micro beam experiments ({approx}1 x 1 {mu}m{sup 2}) in the hard-X-ray regime (4 - {approx}22 keV) and allows to combine micro X-ray fluorescence (micro-XRF), micro X-ray absorption spectroscopy (micro- XAS), and micro X-ray diffraction (micro-XRD) investigations with radioactive samples. Furthermore, the potential of micro-XRF/XAS/XRD for ...

2005-07-01

88

Estimation of X-rays dose in the crystals of final thickness  

International Nuclear Information System (INIS)

A calculation method of the X-ray radiation dose (energy of gamma- radiation remains in the range of energies where the mechanism of photoelectric absorption is the prevailing one) absorbed in the absorbers of final thickness is suggested. Calculations of resorption of secondary radiation (characteristic fluorescences) in the substance and kinetic energy of photoelectrons caused by this resorption (it would be enough to consider one or two hard series) are presented. Calculation of the spectrum of photoelectron energy yield in TeInSe_2 monocrystal for 0.1-0.5 A range of X-ray radiation is conducted by the developed methods.

89

A Virtual Young's Double Slit Experiment for Hard X-ray Photons  

CERN Document Server

We have implemented a virtual Young's double slit experiment for hard X-ray photons with micro-fabricated bi-prisms. We observe fringe patterns with a scintillator, and quantify interferograms by detecting X-ray fluorescence from a scanned 30nm Cr metal film. The observed intensities are best modeled with a near-field, Fresnel analysis. The maximum fringe number in the overlap region is proportional to the ratio of real to imaginary parts refractive index of the prism material. The horizontal and vertical transverse coherence lengths at beamline APS 8-ID are measured.

2009-01-01

90

Removal of Cr(III) from aqueous solutions using zeolite NaY prepared from rice husk ash  

International Nuclear Information System (INIS)

The efficiency of the synthesized zeolite NaY from rice husk ash (RHA) in the removal of Cr(III) from aqueous solution was studied. Zeolite NaY was synthesized from RHA via seeding technique and the identification of its structure was done by X-ray Diffraction (XRD) technique and the elemental analysis was carried out by X-ray Fluorescence (XRF). The physicochemical properties which were related to the use of the zeolite NaY as a sorbent was also investigated. The synthesized zeolite NaY has higher cation exchange capacity (CEC) than the commercial zeolite NaY due to the higher amount of sodium content in the synthesized as well as the lower ratio of silica to alumina. The synthesized zeolite NaY together with the commercial one as comparison was used in the sorption of the Cr(III) in aqueous solution by batch sorption experiments. The kinetic study showed that the Cr(III) uptake by ...

2007-01-01

91

Development of sialon using Yttria and alumina as additive  

International Nuclear Information System (INIS)

Full text: The production of #beta#-sialon from kaolinite and carbon has been studied using Hulu Langat Kaolin and activated carbon as raw materials. The sintered temperature is shown to play a prominent role in the process of sialon conversion. Apart from temperature, nitrogen flow rate is also affect the production of #beta#--sialon. This study was carried out on the effect of additive, Y_2O_3 and Al_2O_3 at different temperature that will be mixed and sintered. The additives are expected to affect the formation of #beta#--sialon and Y-sialon upon the synthesis. The mineral and phase development was analysed using X-Ray Diffraction technique (Rigaku Geigerflex) while its chemical compositions through X-Ray Fluorescent Spectrophotometer (Shimadzu XRF 1700) and the particle size distribution analysis through Particle Size Analyser (Horiba, CAPA 700). The observed changes in the ...

2005-08-16

92

XRF and PIXE method as trols for the element analysis of metallic glasses  

International Nuclear Information System (INIS)

The radionuclide X-ray fluorescence and particle induced X-ray emission methods were used for rapid and nondestructive analysis of metallic glasses. The methods were compared for accuracy and precision with the atomic absorption method. Some results of the analyses of Fe_xNi_8_0_-_xB_2_0 materials are briefly reviewed. The distribution of elements along the width as well as the length and a qualitative analysis of the composition of material surfaces are considered. (author).

1986-01-01

93

XRF and PIXE analysis of metallic glasses  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence and particle induced X-ray emission methods were used for a rapid and nondestructive analysis of metallic glasses. The methods are compared in accuracy and precision with the atomic absorption method. Some results of analyses of Fe_xNi_8_0_-_xB_2_0 materials are briefly reviewed. The distribution of elements along the width and length, and a qualitative analysis of the composition of material surfaces are considered. (author) 3 refs.

1987-05-01

94

X-ray spectral microanalysis of component redistribution in finely dispersed two-phase alloys  

International Nuclear Information System (INIS)

It is shown that it is necessary to take into account locality of the analysis and to introduce additional corrections for partial capture of matrix and fluorescent subexcitation by matrix during quantitative X-ray spectral microanalysis of finely dispersed materials. Cast two-phase (#alpha#+#beta#) titanium alloy VT3-1 is chosen as an investigation object.

95

Analysis of titanium and zirconium in red mud with energy dispersive x-ray spectrometry  

Energy Technology Data Exchange (ETDEWEB)

An energy dispersive x-ray fluorescence technique was used for the determination of Titanium (Ti) and Zirconium (Zr) in red mud by using a standard addition method. An annular {sup 241}Am source is employed for excitation of K shells of elements. 13 refs., 2 figs., 1 tab.

1996-11-01

96

Element distribution in the brain sections of rats measured by synchrotron radiation X-ray fluorescence  

International Nuclear Information System (INIS)

The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO_3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in ...

2004-02-27

97

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

99

X-ray phase imaging using a X-ray tube with a small focal spot. Improvement of image quality in mammography  

International Nuclear Information System (INIS)

Phase contrast X-ray imaging has been studied intensively using X-rays from synchrotron radiation and micro-focus X-ray tubes. However, these studies have revealed the difficulty of this technique's application to practical medical imaging. We have created a phase contrast imaging technique using a molybdenum X-ray tube with a small focal spot size for mammography. We identified the radiographic conditions in phase contrast magnification mammography with a screen-film system, where edge effect due to phase contrast overcomes geometrical unsharpness caused by the 0.1 mm-focal spot of a molybdenum X-ray tube. The edge enhancement due to phase imaging was observed in an image of a plastic tube, and then geometrical configuration of the X-ray tube, the object and the screen-film system was determined for phase imaging of ...

2002-03-01

100

Zinc determination in medicinal powders by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

X-ray fluorescence analysis was used to determine the zinc content of the ''Perilacin'' powder and the ZnO content of the ''Epiderman-pix'' powder. The characteristic Ksub(#alpha#) line of zinc was excited using a "1"4"7Pm/Mo source (10"7 s"-"1) and the molybdenum Ksub(#alpha#) line (17.47 keV). 4 to 5% Zn and 45 to 49% ZnO were determined with a NaI(Tl) scintillation detector. The radiation intensity was found to decrease with particle size. (M.K.).

1977-01-01

101

The use of x-ray fluorescence in the detection of inorganic elements in medicines drugs  

International Nuclear Information System (INIS)

Based on the instrumental wavelength dispersive X-ray fluorescence technique of analysis (W D-X R F), the inorganic elements in four samples of commercial medicines drugs were analyzed. The samples were used without any chemical separation of the elements or chemical pre-treatment. Eleven elements could be identified, namely Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu and Zn. However, Si, Ti and Mn have not been mentioned in the printed instructions for the use of the medicines drugs by the producers. (author)

102

Identification of elements in plant drugs and their water infusion using X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The present work gives preliminary results of analysis of drug mixtures (NEPHROSAL tea bag) and its water infusion. In a sample of dried drugs the elements K, Ca, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Pb were identified, whereas in their water infusion only Ca, Mn, Zn and Sr were found. The method applied was radionuclide X-ray fluorescence analysis using a radionuclide source "1"0"9Cd, a Si/Li semiconductor detector and a multichannel analyzer Canberra 8100. (author) 6 refs.; 3 figs.

8100-01-01

103

Photon-induced L-shell x-ray intensity ratio for elements with 73 #<=# Z #<=#83 in the energy range 17 #<=# E #<=# 47 keV  

International Nuclear Information System (INIS)

The L-shell x-ray intensity ratios I(L_#beta#)/I(L_#alpha#) and I(L_#gamma#)/I(L_a_l_p_h_a) for elements with 73 #<=# Z #<=# 83 have been measured at photon incident energies of 17.8, 25.8 and 46.9 keV. The emitted x-rays were measured with a Si(Li) detector system. The results for Re, Pt and Tl are being reported for the first time. A comparison is made of the experimental results with the calculated values obtained by using the theoretical x-ray emission rates, subshell ionisation cross sections, subshell fluorescence yields and Coster-Kronig transition probabilities. The experimental results are in reasonable agreement with the theoretical values. (author).

1988-01-01

104

Measurements and calculations of M-shell X-ray production in Er, Yb and Lu by 0.75-6 MeV He ions  

Energy Technology Data Exchange (ETDEWEB)

M-shell X-ray production cross sections for the light rare-earth elements of {sup 68}Er, {sup 7}Yb and {sup 71}Lu have been measured for incident {sup 4}He{sup +} ions in the energy range from 0.75 to 6 MeV. The measured X-ray production cross sections are compared to the predictions of the First Born approximation, the ECPSSR theory and the ECUSAR theory. A comparison of the ytterbium M-shell X-ray production cross sections with these theories is made for two different sets of fluorescence yields and Coster-Kronig factors that are further modified for multiple ionization.

2005-12-15

106

Experimental study of X-ray vidicon  

International Nuclear Information System (INIS)

(1972). USSR Sviryakin, DI Manets, AI Kolupaev, AN v. 213 p. 111-114.

107

Total M shell X-ray production cross sections and average fluorescence yields in 11 elements from Tm to U at photon energy of 5.96 keV  

International Nuclear Information System (INIS)

Total M shell X-ray production cross section for 11 elements with 69 #<=# Z #<=# 92 have been measured using an incident photon energy of 5.96 keV. Measurements have been performed using an "5"5Fe annular source and a Si(Li) detector. Average M shell fluorescence yield at each incident photon energy has been deduced, using the experimental total M X-ray production cross section and theoretical M shell photoionization cross section. Present experimental results are compared with other experimental and theoretical values. Reasonable agreement (to within 0.3-28%) is typically obtained between present and other experimental and theoretical values.

2005-04-01

108

[Study of body composition by potassium-40 measurement in patients with breast and uterine cancer].  

Science.gov (United States)

Total potassium was assayed in 150 normal weight and obese females (cervical carcinoma-52, endometrial carcinoma-25 and breast cancer-73) by measurements of 40K spontaneous radiation in a low-background chamber. Control group included 30 healthy and 25 obese females. Computations of body cell and extracellular mass and fat were carried out on the basis of the said measurements. Extracellular fluid volume was measured in 38 patients by X-ray fluorescence method using sodium bromide. The results pointed to a body cell mass deficit matched by increased extracellular mass due to a higher fat level in patients with breast, endometrial and cervical carcinoma. The said correlation was particularly pronounced in obese patients. The beneficial effect of treatment was more often observed in patients with normal body weight. PMID:3739295

1986-01-01

109

Synthesis, crystal structure, spectroscopic properties, antibacterial activity and theoretical studies of a novel difunctional acylhydrazone  

British Library Electronic Table of Contents (United Kingdom)

A novel difunctional acylhydrazone has been synthesized by the reaction of 5-methylisoxazole-4-carboyl hydrazine with benzaldehyde and characterized by X-ray crystallography and spectroscopy. The obtained results demonstrate the crystal belongs to triclinic, space group Formula Not Shown . Moreover, the spectroscopic properties were evaluated through density functional theory (DFT) and time-dependent density functional theory (TD DFT) calculations. The results reveal that UV-Vis absorption peaks at 194, 217.5 and 290.5nm are mainly attributed to (p, p)p*, partly (p, p)p* and partly pp*, and predominantly pp*, respectively, with intraligand charge-transfer transition (ILCT) character. The fluorescence emission peak at 485.96nm should be assigned to ILCT. In addition, the results of antibact...

2011-01-01

110

Nuclear analytical techniques in Cuban sugar industry  

Energy Technology Data Exchange (ETDEWEB)

This paper is a review concerning the application of Nuclear Analytical Techniques in the Cuban sugar industry. The most complete elemental composition of final molasses (34 elements) and natural zeolites (38) this last one employed as an auxiliary agent in sugar technological processe4s has been performed by means of instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence Analysis (XRFA). The trace elemental sugar cane soill-plant relationship and elemental composition of different types of Cuban sugar (raw, blanco-directo and refine) were also studied. As a result, valuable information referred to the possibilities of using these products in animal and human foodstuff so as in the other applications are given. (author). 34 refs., 6 figs., 1 tab.

1997-12-01

111

Elemental analysis of savannah grass' burning ashes  

International Nuclear Information System (INIS)

In order to quantify the biomass burning emissions, the main atmospheric pollution source of tropical and subtropical regions, we carried out the analysis of ashes that are also formed during these fires. To this end, we developed analytical methods to characterize the composition of savannah grass burning ashes by using X-ray fluorescence for mineral elements and microanalysis for C, H, O and N. Samples used in this work have been collected during laboratory combustion experiments, with chemically well-defined natural savannah grasses from Ivory Coasts and South Africa. The reproducibility and efficiency of different developed procedures have been studies. The analytical relative precision is generally better than 5%. This development has allowed to establish, for the first time, the global mass balance of ashes resulting from savannah grass burning. (authors). 16 refs., 3 figs., 8 tabs.

112

Tissue oxygenation in a murine SCC VII tumor after X-ray irradiation as determined by EPR spectroscopy  

UK PubMed Central (United Kingdom)

PurposeThe goal of this study was to clarify the dynamics of tumor oxygen (partial pressure of oxygen, pO2) in SCC VII murine tumors in mice after X-ray...Full Text Available

2008-03-01

113

Noise Characterization of Polycrystalline Silicon Thin Film Transistors for X-ray Imagers Based on Active Pixel Architectures  

UK PubMed Central (United Kingdom)

An examination of the noise of polycrystalline silicon thin film transistors, in the context of flat panel x-ray imager development, is reported. The study was conducted in the spirit of exploring...Full Text Available

2008-01-01

114

A comparison of iterative algorithms and a mixed approach for in-line x-ray phase retrieval  

UK PubMed Central (United Kingdom)

Previous studies have shown that iterative in-line x-ray phase retrieval algorithms may have higher precision than direct retrieval algorithms. This communication compares three iterative phase...Full Text Available

2009-08-15

115

Measurements of K-shell x-ray production cross sections and K to L and M-shell radiative vacancy transfer probabilities for Nd, Eu, Gd, Dy and Ho at excitation with 59.5 keV photons in an external magnetic field  

International Nuclear Information System (INIS)

The effect of the #+-# 0.75 T external magnetic field on the K_#alpha#_1, K_#alpha#_2, K_#beta#_'_1 and K_#beta#_'_2 x-ray production cross sections and radiative vacancy transfer probabilities from K-shell to L2 and L3 subshells and M-shell for ferromagnetic Nd, Gd and Dy and paramagnetic Eu and Ho have been investigated, using the 59.5 keV incident photons. K-shell fluorescence yields and K x-ray intensity ratios for these elements have been determined in the external magnetic field also. The K x-rays from different targets were detected using a high-resolution Si(Li) semiconductor detector. For B = 0, the present experimental results were compared with the experimental and theoretical data in the literature. The results show that K-shell fluorescence parameters such as photoionization cross section, fluorescence yield, radiation rates, vacancy transfer ...

2006-06-19

116

X-ray dosimetry of TlGaSe_2 single crystals  

International Nuclear Information System (INIS)

TlGaSe_2 compound belongs to group of layered semiconductors of A"3B"3C_2"6-type. Photoelectric and optical properties of TlGaSe_2 single crystals were investigated in detail. Influence of gamma-, electron and neutron radiation on photoelectric properties of TlGaSe_2 single crystals is investigated too. The present work deals with experimental results relative to X-ray dosimetric characteristics of TlGaSe_2 crystals at 300 K. X-ray conductivity and X-ray dosimetric characteristic measurements are carried out in low load resistance regime. The source of X-ray radiation is the installation of X-ray diffraction analysis (URS-55a) with the BCV-2(Cu). Intensity of X-ray radiation (E) is regulated by measurement with current variation in tube at each given value of X-ray radiation dose E (R/min) are measured by crystal dosimeter DRGZ-02. ...

117

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

Energy Technology Data Exchange (ETDEWEB)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L{sub {gamma}1} X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L{sub {gamma}1}/L{sub {beta}1} X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-20

118

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

International Nuclear Information System (INIS)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L_#gamma#_1 X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L_#gamma#_1/L_#beta#_1 X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-01

119

Genetic and somatic risks in X-ray diagnosis  

International Nuclear Information System (INIS)

Based on a literature study an actual summary of the risk-utility problems in X-ray diagnosis is outlined due to the Recommendations of the International Commission for Radiation Protection (ICRP publication 26/1977). Papers demonstrating quantitative assessment of the somatic and genetical risk in X-ray examination are preferably cited and evaluated. It is concluded that the somatic and genetical risk is low in diagnostic ratiology. However, it must not be neglected and has always to be compared to the utility of an examination as well as to other risks of the examination. (author).

1982-01-01

120

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

CERN Document Server

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

2003-01-01

121

Theoretical transition energies, lifetimes and fluorescence yields of multiply ionized silicon  

Energy Technology Data Exchange (ETDEWEB)

Theoretical x-ray transition energies, lifetimes and partial multiplet fluorescence yields are presented for all spectroscopic terms of electron configurations with a single K-shell vacancy and varying number of electrons in the L-shell and M/sub 1/-subshell for multiply-ionized silicon. 9 tables.

1982-01-01

122

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

Energy Technology Data Exchange (ETDEWEB)

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

1983-01-01

123

Multielement analysis of air samples. Determination of iron, zinc, lead, and bromine content by the radionuclide X-ray fluorescence analysis  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis for nondestructive determination of Fe, Zn, Pb, and Br in air samples collected on nitrocellulose membrane filter Synpor 4 is described. A /sup 238/Pu source for the excitation and a semiconductor Si/Li detector for the detection of characteristic and L-fluorescent radiation of the above elements were used. A correction method based upon the measurements of simple or multiple Compton scattering for compensation of varying mass per unit area values in sample deposits was theoretically proposed and experimentally tested. The results obtained both with and without the correction were compared and good agreement with those given by atomic absorption spectrometry was observed.

1981-01-01

124

Theoretical modelling of X-ray fluorescence signals for different lunar compositions and dependence on solar activity  

British Library Electronic Table of Contents (United Kingdom)

We present a forward modelling technique for calculating the surface X-ray spectra for a variety of lunar terrains. Our calculations considered variations in solar fluxes from solar quiescent condition to large flare activity (M1 flare), and expected elemental concentrations in the target, as well as yield, instrumental, and viewing geometry parameters for X-ray induced fluorescence from the lunar surface. Additionally, we present estimates of anticipated XRF signals from prominent Ka lines observable by a collimated 14cm2 X-ray detector from a 100km lunar orbit with 20km spatial resolution. Our results show that Mg, Al and Si characteristic Ka lines can be observed for all solar conditions. The Ca Ka lines line can be differentiated from a fixed background during more energetic solar cond...

2010-01-01

125

K/sub. beta. //K/sub. cap alpha. / transition probability ratios from the measurement of fluorescent X-ray intensities of some lanthanide compounds  

Energy Technology Data Exchange (ETDEWEB)

The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios. The measured relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios were compared to ...

1987-01-01

126

K/sub #beta#//K/sub #alpha#/ transition probability ratios from the measurement of fluorescent X-ray intensities of some lanthanide compounds  

International Nuclear Information System (INIS)

The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios. The measured relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios were compared to the calculated ...

1987-01-01

127

Hard X-ray identification of Eta Carinae and steadiness close to periastron  

CERN Document Server

Context: The colliding-wind binary Eta Car exhibits soft X-ray thermal emission that varies strongly around periastron, and non-thermal emission seen in hard X-rays and gamma-rays. Aims: To definitively identify Eta Car as the source of the hard X-ray emission, to examine how changes in the 2-10 keV band influence changes in the hard X-ray band, and to understand more clearly the mechanisms producing the non-thermal emission using new INTEGRAL observations obtained close to periastron. Methods: A Chandra observation encompassing the ISGRI error circle was analysed, and all other soft X-ray sources (including the outer shell of Eta Car itself) were discarded as likely counter-parts. New hard X-ray images of Eta Car were studied close to periastron, and compared to previous observations far from periastron. Results: The INTEGRAL component, ...

2010-01-01

128

Energetic electrons in impulsive and extended solar flares as deduced from flux correlations between hard X-rays and microwaves  

Energy Technology Data Exchange (ETDEWEB)

The peak flux relationship between hard X-rays and microwaves from solar flares is studied using about 400 events simultaneously recorded with the hard X-ray burst spectrometer on the SMM satellite and the Nobeyama 17 GHz radiometer. The data indicate that the hard X-ray and microwave peak fluxes correlate best for X-ray energies of less than about 80 keV for impulsive flares and greater than about 360 keV for extended flares. By postulating that electrons responsible for microwave emission at 17 GHz are those emitting hard X-rays at these photon energies, it is concluded that: (1) in impulsive flares, microwaves at about 20 GHz are emitted mainly by electrons of less than about 200 keV from a layer through which the electrons stream down into the thick-target hard X-ray source; and (2) in extended flares, microwaves are emitted mainly by ...

1988-01-01

129

Development of a dual-detector X-ray imaging system for phase retrieval study  

International Nuclear Information System (INIS)

Based on a recently introduced phase X-ray imaging approach, a dual-detector prototype was developed for in-line X-ray phase imaging and phase retrieval utilizing a micro-focus X-ray source and two computed radiography (CR) cassette detectors. The system was built on a horizontal optical rail to facilitate manual adjustment of the positions of the X-ray source, the sample and the detectors. The novel design of the detector-1 is essential, it detects a portion of radiation to form an attenuation image; allows the rest of radiation to reach the detector-2 to form a phase contrast image, and the two images are used to retrieve a phase map. The two detectors are balanced for optimal phase-retrieval with reasonable radiation dose to the object to be imaged. The system was examined in terms of the linearity, the fractions of the X-ray photons detected by the two detectors, respectively ...

2007-01-01

130

M shell x-ray emission in Pb, Th and U due to L_3 to M sub shell transfer of vacancies  

International Nuclear Information System (INIS)

M shell x-ray production cross sections in thick targets of Pb, Th and U by K x-rays of Rb, Nb and Mo respectively have been measured. As the incident K x-ray energies are above the L_3 edge but below L_2 edge energies of the respective target elements under reference, the M x-rays are produced not only due to direct interaction of incident photons with M shell electrons but also due to the shift of the L_3 subshell vacancies to the M shell. The experiment has been performed using a double reflection geometrical setup with a 1 Curie"2"4"1Am gamma ray source and a Si (Li) x-ray spectrometer. The measured values have been compared with those calculated using known values of M and L_3 subshell photoionisation cross sections and fluorescence yields etc., wherever possible. The component of the percentage contribution due to shift of L_3 subshell vacancies to M shell ...

131

X-ray fluorescence in research on Czech cultural monuments  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis (RXRFA), as a non-destructive method, relatively simple and allowing measurements to be carried out in situ, is an excellent tool in research on various objects of art. A range of artefacts have been investigated by our laboratory, in part for the purposes of history of art and in part as a basis for restoration works - medieval frescoes in some Czech castles and churches, metal sculptures and objects of applied art, paints and inks of old manuscripts, paintings. Some of these are among the most valuable monuments in the Czech cultural heritage. The contribution of the results of the tests to the investigation of their 'life story' and, in some cases, to their conservation, is not negligible. Later additions and repairs can be recognised, and materials and technologies that are close to their historic counterparts can be used in restoration work.

2004-01-01

132

X-ray fluorescence in research on Czech cultural monuments  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis (RXRFA), as a non-destructive method, relatively simple and allowing measurements to be carried out in situ, is an excellent tool in research on various objects of art. A range of artefacts have been investigated by our laboratory, in part for the purposes of history of art and in part as a basis for restoration works - medieval frescoes in some Czech castles and churches, metal sculptures and objects of applied art, paints and inks of old manuscripts, paintings. Some of these are among the most valuable monuments in the Czech cultural heritage. The contribution of the results of the tests to the investigation of their 'life story' and, in some cases, to their conservation, is not negligible. Later additions and repairs can be recognised, and materials and technologies that are close to their historic counterparts can be used in restoration work.

2004-01-01

133

Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between...

2011-01-01

134

Instruments for X-ray fluorescence analysis and spectrometry  

International Nuclear Information System (INIS)

The radionuclide X-ray fluorescence analyzer consists of a source changer and a sample changer. "5"5Fe, "1"0"9Cd and "2"4"1Am are used as excitation sources. The radiation is detected with a semiconductor Si(Li) detector. The complete assembly of the apparatus consists of an imagine unit, a keyboard, a floppy disc drive, a printer, a console and a rack with analog and digital electronics. Its multichannel amplitude analyzer consists of power supplies, a high voltage supply, a linear amplifier, an analog-to-digital converter and a computer. The technical specifications are given. The control and data processing system is controlled with an MHB 8080A microprocessor. Software for semiconductor gamma spectrometry and for quantitative gamma spectrometry will be supplied with the equipment. (E.S.). 3 figs., 4 refs.

135

Future instrumentation for the study of the Warm-Hot Intergalactic Medium  

CERN Document Server

We briefly review capabilities and requirements for future instrumentation in UV- and X-ray astronomy that can contribute to advancing our understanding of the diffuse, highly ionised intergalactic medium.

2008-01-01

136

A convolution/superposition method using primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance: a theoretical study on 10-MV X-ray dose calculations in thorax-like phantoms  

British Library Electronic Table of Contents (United Kingdom)

A convolution/superposition method is proposed for use with primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance. It should be noted that the number of energy bins is usually about ten, and that the reconstructed X-ray spectra can reasonably be applied to media with a wide range of effective Z numbers, ranging from water to lead. The study was carried out for 10-MV X-ray doses in water and thorax-like phantoms with the use of open-jaw-collimated fields. The dose calculations were made separately for primary, scatter, and electron contamination dose components, for which we used two extended radiation sources: one was on the X-ray target and the other on the flattening filter. To calculate the in-air beam intensities at po...

2011-01-01

137

Phase, residual stress, and texture in triode-sputtered tantalum coatings on steel. Final report  

Energy Technology Data Exchange (ETDEWEB)

This work analyzes the unoptimized prototype triode-sputtered, 150 microns thick tantalum coatings deposited with a 2.5 microns niobium underlayer on the bore of a large-diameter A723 steel cylinder. The coating was deposited for wear and erosion protection by Pacific Northwest National Laboratory. The phase determination was based on X ray diffraction analysis, wavelength dispersive X ray fluorescence analysis, energy dispersive X ray analysis, and hardness and electrical resistivity measurements. Both X ray diffraction and radius-of- curvature methods were used to determine residual stresses. A locally developed high-resolution pole figure technique was used to perform texture analysis. The post-firing, debonded coating showed alpha-tantalum, preferred 110 orientation, high surface stresses, ...

1998-07-01

138

Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization  

International Nuclear Information System (INIS)

The measurements of the L X-ray intensity ratio I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?) and I(L?)/I(L?) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV ?-rays from a filtered radioisotope 241Am was used, and by the radioactive decay of 160Tb, 160Er, 173Lu, 182Re, 201Tl, 203Pb and 207Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L?/L?), I(L?/L?), I(L?/L?), I(L?/L?) and I(L?/L?) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional X-ray emission rates, Coster-Kronig transition probabilities. It was observed that present values agree with previous theoretical and other available ...

2008-05-22

139

Nanofocusing refractive X-ray lenses  

Energy Technology Data Exchange (ETDEWEB)

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

2010-02-05

140

Study of metal concentration in sediment of some springs of Lebanon  

International Nuclear Information System (INIS)

Full text.Surficial sediment samples were collected from seventeen springs distributed all over Lebanon (east, west, north and south). Concentrations of metals Ca, Fe, Mn, Ni, Cu, Cr, Zn and Pb were determined by energy dispersive x-ray fluorescence technique. Irradiation was done by the radioisotope source Cd-109 and the detection by an EG and G Si(Li) detector. These analysis was done in attempt to assess the impact of anthropogenic sources on ground water quality. Metals concentration in sediment were found to be (Ca:0.05-47%, Fe:0.24-4.2%, Cr:study were of the same order of magnitude as those obtained ...

1999-11-02

141

Selective adsorption of uranium on activated charcoal from electrolytic aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

Adsorption of uranium onto various solids is important from purification, environmental, and radioactive waste disposal points of view. Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. {Delta}H{degrees} and {Delta}S{degrees} were calculated from the slope and intercept of plots ln K{sub D} vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity; consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 ml of 3 M HNO{sub 3} solution. A wavelength dispersive x-ray fluorescence spectrometer was used for ...

1992-02-01

142

FUV and X-ray absorption in the Warm-Hot Intergalactic Medium  

CERN Document Server

The Warm-Hot Intergalactic Medium (WHIM) arises from shock-heated gas collapsing in large-scale filaments and probably harbours a substantial fraction of the baryons in the local Universe. Absorption-line measurements in the ultraviolet (UV) and in the X-ray band currently represent the best method to study the WHIM at low redshifts. We here describe the physical properties of the WHIM and the concepts behind WHIM absorption line measurements of H I and high ions such as O VI, O VII, and O VIII in the far-ultraviolet and X-ray band. We review results of recent WHIM absorption line studies carried out with UV and X-ray satellites such as FUSE, HST, Chandra, and XMM-Newton and discuss their implications for our knowledge of the WHIM.

2008-01-01

143

Emission Line Spectra in the Soft X-Ray Region 20-75 (Angstrom)  

Energy Technology Data Exchange (ETDEWEB)

As part of a project to complete a comprehensive catalogue of astrophysically relevant emission lines in support of new-generation X-ray observatories using the Lawrence Livermore electron beam ion traps EBIT-I and EBIT-II, we studied emission lines of argon and sulfur in the soft X-ray and extreme ultraviolet region. Here we present observations of Ar IX through Ar XVI and S VII through S XIV between 20 and 75 {angstrom} to illustrate our work.

2002-06-18

144

X-Ray Fluorescence in Research on the Cultural Heritage  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented ...

2001-09-15

145

X-Ray Fluorescence in Research on the Cultural Heritage  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented ...

2001-09-01

146

Multielement analysis of air samples  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis for nondestructive determination of Fe, Zn, Pb, and Br in air samples collected on nitrocellulose membrane filter Synpor 4 is described. A "2"3"8Pu source for the excitation and a semiconductor Si/Li detector for the detection of characteristic and L-fluorescent radiation of the above elements were used. A correction method based upon the measurements of simple or multiple Compton scattering for compensation of varying mass per unit area values in sample deposits was theoretically proposed and experimentally tested. The results obtained both with and without the correction were compared and good agreement with those given by atomic absorption spectrometry was observed. (author).

1981-01-01

147

Use of x-ray imaging for evaluation of superconducting ceramics fabricated by PIT method  

Energy Technology Data Exchange (ETDEWEB)

High-spatial-resolution microfocus-based X-ray imaging technology, both real-time and film, has been used to study the thickness variation that occurs in the oxide core of silver-sheathed BSCCO ribbons produced by the powder-in-tube method. This thickness variation (also called ``sausaging``) occurs during incremental rolling and degrades the critical current densities of the ribbons. Using X-ray image data the authors determined the onset and severity of sausaging. Onset occurred at a ribbon thickness of 203 {micro}m, and the severity increased with subsequent rolling reductions. Scanning electron microscopy was used to confirm the X-ray image data. X-ray imaging provides several advantages over more traditional methods for characterizing the superconductors such as optical or scanning electron microscopy. The X-ray imaging provides nondestructive information ...

1993-08-01

148

Unique Properties of Thermally Tailored Copper: Magnetically Active Regions and Anomalous X-ray Fluorescence Emissions  

UK PubMed Central (United Kingdom)

When high-purity copper (≥99.98%wt) is melted, held in its liquid state for a few hours with iterative thermal cycling, then allowed to resolidify, the ingot surface is found to have...Full Text Available

2009-12-24

149

Standard deviation of measurement results in x-ray fluorescence spectrometry  

International Nuclear Information System (INIS)

The standard deviation of measurement results of a given element in XRF spectrometry depends on three factors: concentration and concentration region, atomic number and matrix. The effects of these factors were investigated by an XRF instrument type ARL 72.000 for aluminium metal, bauxite-red mud and aluminium using computerized data processing. A comparison of linear and nonlinear relation between concentration and the result of XRF analysis was made for the determination of standard deviation. (R.P.).

1984-11-13

150

Some optimization measurements and parameters of a radionuclide X-ray fluorescence spectrometer  

International Nuclear Information System (INIS)

An irradiation head with sample holders is described and measurement geometry is reported. Measurements were made for optimizing the distance between the source and the sample and for optimizing the sample diameter. The optimal distance between the source and the sample does not depend on the collimator diameter. The sample diameter should not exceed 30 - 35 mm. Sensitivity and detection limits were determined for Zn, Pb and Br and calibration curves were plotted. (M.D.) 6 figs., 2 tabs., 4 refs.

1986-01-01

151

Radionuclide X-ray fluorescence analysis of drinking water using preconcentration of trace metals on chelating cellulose exchanger ostsorb-oxin  

International Nuclear Information System (INIS)

Determination of Cr, Fe, Cu, Zn and Pb in drinking water preconcentrated on a chelating ion exchanger of Czechoslovak production is described. The analytical system consisted of a radionuclide source "2"3"8Pu, a Si/Li semiconductor detector and a multichannel analyzer. Results are compared with trehshold limit values recommended for drinking water. (author) 9 refs.; 2 figs.

1992-04-01

152

Radioanalytical chemistry. Vol. 2  

International Nuclear Information System (INIS)

This volume of the monograph covers the following topics: activation analysis, non-activation interaction analysis (elastic scattering of charged particles, absorption and backscattering of beta radiation and photons, radionuclide X-ray fluorescence analysis, thermalization, scattering and absorption of neutrons, use of ionization caused by nuclear radiation, use of ionization by alpha or beta radiation for the measurement of pressure, density and flow rate of gases), and automation in radioanalytical chemistry. (P.A.).

1989-01-01

153

Identification and determination of elements in Taraxacum officinale plant from different Bratislava localities  

Energy Technology Data Exchange (ETDEWEB)

Elements Ti, Mn, Fe, Ni, Cu, Zn, Pb, Br, Rb and Sr were determined by the method of radionuclide X-ray fluorescence analysis with semiconductor detection in samples of Taraxacum officinale from various localities of Bratislava. The dependence of their content on the source and the degree of the air pollution was found out.

1983-01-01

154

Identification and determination of elements in Taraxacum officinale plant from different Bratislava localities  

International Nuclear Information System (INIS)

Elements Ti, Mn, Fe, Ni, Cu, Zn, Pb, Br, Rb and Sr were determined by the method of radionuclide X-ray fluorescence analysis with semiconductor detection in samples of Taraxacum officinale from various localities of Bratislava. The dependence of their content on the source and the degree of the air pollution was found out. (author).

1983-01-01

155

Heavy metals in welding fumes  

Energy Technology Data Exchange (ETDEWEB)

Fe, Mn, Ni, V, Ti and Mo were determined in aerosols from manual arc welding. Samples of welding aerosols were trapped on a Synpor 4 filter. The amount of determined elements in aerosols was detected using the method of radionuclide X-ray fluorescence analysis. A /sup 241/Am annular source was used as the source of excitation radiation and radiation was processed using a Si(Li) spectrometer.

1984-10-01

156

Heavy metals in welding fumes  

International Nuclear Information System (INIS)

Fe, Mn, Ni, V, Ti and Mo were determined in aerosols from manual arc welding. Samples of welding aerosols were trapped on a Synpor 4 filter. The amount of determined elements in aerosols was detected using the method of radionuclide X-ray fluorescence analysis. A "2"4"1Am annular source was used as the source of excitation radiation and radiation was processed using a Si(Li) spectrometer. (E.S.).

1984-01-01

157

Determination of the Sr/Ca ratio in bones by XRFA  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of Sr/Ca ratio in bones to test the influence of a diet on this ratio. Significant differences were observed for Sr/Ca ratio in bones of various animals. Only small differences in the Ca/Sr ratio were observed for the samples of various prehistoric human bones. (author) 4 refs.; 4 tabs.

1989-11-01

158

Determination of heavy metals in welders' working environment using nuclear analytical methods  

International Nuclear Information System (INIS)

Technological processes of welding are significant sources of pollution in the working area. Evaluation of chemical quality of working area was made by means of radionuclide x-ray fluorescence analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed. (author).

1985-01-01

159

Determination of heavy metals in welders' working environment using nuclear analytical methods  

Energy Technology Data Exchange (ETDEWEB)

Technological processes of welding are significant sources of pollution in the working area. Evaluation of chemical quality of working area was made by means of radionuclide x-ray fluorescence analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed.

1985-01-03

160

Determination of heavy metals in industrial wastewaters and their influence on activated sludge biocenose  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and "2"3"8Pu exciting source was used in the determination of Cr, Fe, Ni, Cu, and Zn content in industrial wastewaters. Simultaneously, the effects of the wastewaters on activated sludge biocenose were evaluated. (author) 6 refs.; 1 fig.; 1 tab.

1994-03-01

161

Determination of Mg, Al, Si, Cl and K in some medicinal plants by NAA and REA methods  

Energy Technology Data Exchange (ETDEWEB)

Trace elements have been determined in biological samples including pepperwort, thyme, plantain, blessed thistle and common comfrey as well as cabbage leaves and milk powder. Concentrations of Al, Si, and Cl have been determined by fast neutron activation analysis while, in the case of Mg-, K, and Cl the X-ray fluorescence method was used.

1982-07-26

163

Application of isotope-excitation x-ray fluorescence (XRF) analysis for aluminium production  

International Nuclear Information System (INIS)

An energy sensitive Si(Li) detector XRF analyzer built by ATOMKI, Hungary, has been applied for various analytical purposes in alumina production at the Almasfuezitoe Alumina Company, Hungary. Specifically, the CaO content in red mud was determined by the new XRF technique using isotope excitation sources. The analysis of other components is under way. (R.P.).

164

A simple system of instruments for radionuclide X-ray fluorescence analysis in nonferrous metallurgy  

International Nuclear Information System (INIS)

Proceeding from commercially available instruments, a simple measuring system has been established, which renders possible fast and simple discontinuous analysis of individual elements. This measuring system is described, giving some examples of utilization in nonferrous metallurgy (mining, ore dressing, metallurgical treatment), and specific details, such as error of measurement, ranges of measurement and limits of utilization. (author).

1979-01-01

165

2. Nuclear analytical methods and environmental protection  

International Nuclear Information System (INIS)

The first step in the protection of the environment is the control of pollutant level in the components of the environment. The application is compared of radionuclide X-ray fluorescence analysis (RXFA) used for this purpose with polarographic and nuclear analytical techniques. The advantage of RXFA is its high sensitivity and selectivity, its low time and cost exactingness. The origins and development of RXFA are described. (Ha).

1983-12-01

166

Recent progress in energy-filtered high energy X-ray photoemission electron microscopy using a Wien filter type energy analyzer  

International Nuclear Information System (INIS)

Energy-filtered X-ray photoemission electron microscopy (EXPEEM) is a microscopy technique which has the potential to provide surface chemical mapping during surface chemical processes on the nanometer scale. We studied the possibilities of EXPEEM using a Wien filter type energy analyzer in the high energy X-ray region above 1000 eV. We have successfully observed the EXPEEM images of Au islands on a Ta sheet using Au 3d_5_/_2 and Ta 3d_5_/_2 photoelectron peaks which were excited by 2380 eV X-rays emitted from an undulator (BL2A) at Photon Factory. Our recent efforts to improve the sensitivity of the Wien filter energy analyzer will also be discussed.

2004-10-15

167

Particle and X-ray damage in pn-CCDs  

Energy Technology Data Exchange (ETDEWEB)

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

2000-01-11

168

Characterization and Source Term Assessments of Radioactive Particles from Marshall Islands Using Non-Destructive Analytical Techniques  

Energy Technology Data Exchange (ETDEWEB)

A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and {sup 241}Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and elemental distribution ...

2005-06-11

169

X-ray diffraction studies of palladium silicide thin films  

Energy Technology Data Exchange (ETDEWEB)

The solid state reaction between a Pd thin film and a Si substrate produces a single new phase, Pd/sub 2/Si, for temperatures <700/sup 0/C. When the substrate is a single crystal of (111) surface orientation, this process is particularly interesting because the silicide grows epitaxially. Growth of epitaxial interfacial Pd/sub 2/Si was the focus of this study using X-ray diffraction techniques.

1985-01-01

170

K_#beta#/K_#alpha# X-Ray Intensity Ratio Studies on the Valence Electronic States of 3d-Transition Metals in some of their Compounds  

International Nuclear Information System (INIS)

Our studies on K#beta#/K#alpha# X-ray intensity ratios of some of the technologically important 3d-transition metal compounds have been reviewed. Comparison of the experimental results with single-configuration Dirac-Fock calculations provided important information on the valence states of the transition metals in various compounds, which can be helpful in understanding the nature of bonding in the compounds. (author)

2000-02-01

171

Structural intermediates in the assembly of taxoid-induced microtubules and GDP-tubulin double rings: time-resolved X-ray scattering.  

UK PubMed Central (United Kingdom)

We have studied the self-association reactions of purified GDP-liganded tubulin into double rings and taxoid-induced microtubules, employing synchrotron time-resolved x-ray solution scattering. The...Full Text Available

1996-05-01

172

Chemical effects on L_#gamma#_1/L_#beta#_1 x-ray intensity ratio of molybdenum compounds  

International Nuclear Information System (INIS)

Chemical effects on the intensity ratio of LX-ray of molybdenum compounds irradiated by 11-keV electrons and by 3-MeV protons were studied using an x-ray crystal spectrometer. It was found that the intensity ratios of L_#gamma#_1/L_#beta#_1 markedly decrease with the increase of ionicity of molybdenum compounds, except for the case of metallic molybdenum. (author).

1987-06-01

173

Changes in the profile structure of the sarcoplasmic reticulum membrane induced by phosphorylation of the Ca2+ ATPase enzyme in the presence of terbium: a time-resolved x-ray diffraction study.  

UK PubMed Central (United Kingdom)

The design of the time-resolved x-ray diffraction experiments reported in this and an accompanying paper was based on direct measurements of enzyme phosphorylation using [gamma-32P]ATP that were employed...Full Text Available

1994-05-01

174

Calculated valence electronic structure of 3d metals for use in the X-ray intensity ratio studies  

Energy Technology Data Exchange (ETDEWEB)

3d occupation numbers of the transition elements corresponding to various types of atomic configurations are calculated by means of the linear muffin-tin orbital (LMTO) method. This data is used with the multiconfiguration Dirac-Fock (MCDF) X-ray intensity ratios to estimate the electron populations of the 3d metals in alloys.

2010-09-15

175

Calculated valence electronic structure of 3d metals for use in the X-ray intensity ratio studies  

International Nuclear Information System (INIS)

3d occupation numbers of the transition elements corresponding to various types of atomic configurations are calculated by means of the linear muffin-tin orbital (LMTO) method. This data is used with the multiconfiguration Dirac-Fock (MCDF) X-ray intensity ratios to estimate the electron populations of the 3d metals in alloys.

2010-09-01

176

M-shell x-ray production by 0.6--4.0-MeV protons in ten elements from hafnium to thorium  

International Nuclear Information System (INIS)

M-shell x-ray production cross sections for selected heavy elements, namely, _7_2Hf, _7_3Ta, _7_4W, _7_5Re, _7_6Os, _7_7Ir, _7_8Pt, _7_9Au, _8_3Bi, and _9_0Th, were measured for protons of energy 0.6--4.0 MeV. The experimental results are compared with the predictions of the first Born and semiclassical approximations for M-shell ionization; these data are also compared with the theory that accounts for the projectile's energy loss and Coulomb deflection as well as for the target's M-shell electron perturbed stationary state and relativistic nature (ECPSSR). Generally, fair agreement between the data and the ECPSSR theory is found. Some systematical discrepancies observed for the lightest elements (Hf, Ta, and W) are explained as possible ambiguities in the M-shell Coster-Kronig factors and fluorescence yields, which were used to convert theoretical M-subshell ionization cross sections to the total M-x-ray production cross ...

178

Depth-profiling of vertical sidewall nanolayers on structured wafers by grazing incidence X-ray flourescence  

British Library Electronic Table of Contents (United Kingdom)

The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, developed an alignment strategy to specify elemental depth profiling in vertical sidewall layers on structured wafers. For this purpose, PTB's irradiation chamber for 200?mm and 300?mm silicon wafers was used to combine total-reflection X-ray fluorescence (TXRF) and grazing incidence XRF (GIXRF) techniques by employing monochromatized undulator radiation of the BESSY II electron storage ring. 3-D test structures were fabricated to develop an optimal alignment strategy allowing for depth profiling in such nanolayers. The test structures consisted of silicon bars with widths/spacings either in the ?m or in the nm range. In order to be able to differentiate the sidewalls more easily from the remainder of ...

2008-01-01

179

X-dosimetry of Tl(InS_2)_1_-_x(FeSe_2)_x single crystals  

International Nuclear Information System (INIS)

Tl(InS_2)_1_-_x(FeSe_2)_x single crystals (where x=0; 0.001; 0.005; 0.01 and 0.015) were grown by the Bridgman-Stockbarger method. Obtained single crystals were crystallized in monoclinic structure. The present paper deals with experimental results relative to X-ray dosimetric characteristics of the Tl(InS_2)_1_-_x(FeSe_2)_x solid solutions at 300 K. Installation URS-55a was the source of radiation. X-ray radiation dose (E) falling on the crystals is measured by the crystalline X-ray dosimeter DRGZ-02. The value of X-ray conductivity coefficient K_#sigma# characterising X-ray sensitivity is defined as K_#sigma#= (#sigma#_E-#sigma#_0)/E#sigma#_0. where #sigma#_E is conductivity under the effect of X-ray radiation by intensity E, #sigma#_0 is conductivity in the lack of radiation. Comparing X-ray dosimetric characteristics of TlInS_2 and ...

2003-09-15

180

The intriguing nature of the high energy gamma ray source XSSJ12270-4859  

CERN Document Server

The nature of the hard X-ray source XSSJ12270-4859 is still unclear though it was claimed to be a magnetic Cataclysmic Variable. We here present a broad-band X-ray and gamma ray study based on a recent XMM-Newton observation and archival INTEGRAL and RXTE data. From the Fermi/LAT 1-year point source catalogue, we tentatively associate XSSJ12270-4859 with 1FGLJ1227.9-4852, a source of high energy gamma rays with emission up to 10GeV. We complement the study with UV photometry from XMM-Newton and ground-based optical and near-IR photometry. The X-ray emission is highly variable showing flares and intensity dips. The X-ray flares consist of flare-dip pairs. Flares are also detected in the UV range but not the dips. Aperiodic dipping behaviour is also observed during X-ray quiescence but not in the UV. The 0.2-100keV spectrum is featureless and ...

2010-01-01

181

X-ray and HeI 1.0830 mu emission from protostellar jets  

CERN Document Server

Context. The high energies of protostellar jets, implied by recent observations of X-rays from such flows, came very much as a surprise. Inferred shock velocities are considerably higher than what was previously known, hence putting even larger energy demands on the driving sources of the jets. The statistics of X-ray emitting jets are still poor, yet a few cases exist which seem to imply a correlation between the presence of HeI 1.0830 mu emission and X-ray radiation in a given source. Aims. This tentative correlation needs confirmation and explanation. If the jet regions of HeI 1.0830 mu emission are closely associated with those producing X-rays, high resolution infared spectroscopy can be used to observationally study the velocity fields in the hot plasma regions of the jets. This would provide the necessary evidence to test and further develop theoretical models of ...

2006-01-01

182

He-like ions as practical astrophysical plasma diagnostics: From stellar coronae to active galactic nuclei  

CERN Document Server

We review X-ray plasma diagnostics based on the line ratios of He-like ions. Triplet/singlet line intensities can be used to determine electronic temperature and density, and were first developed for the study of the solar corona. Since the launches of the X-ray satellites Chandra and XMM-Newton, these diagnostics have been extended and used (from CV to Si XIII) for a wide variety of astrophysical plasmas such as stellar coronae, supernova remnants, solar system objects, active galactic nuclei, and X-ray binaries. Moreover, the intensities of He-like ions can be used to determine the ionization process(es) at work, as well as the distance between the X-ray plasma and the UV emission source for example in hot stars. In the near future thanks to the next generation of X-ray satellites (e.g., Astro-H and IXO), higher-Z He-like lines (e.g., iron) will be resolved, ...

2011-01-01

183

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

CERN Document Server

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

2004-01-01

184

Accretion Properties of A Sample of Hard X-ray (<60keV) Selected Seyfert 1 Galaxies  

CERN Document Server

We examine the accretion properties in a sample of 42 hard (3-60keV) X-ray selected nearby broad-line AGNs. The energy range in the sample is harder than that usually used in the similar previous studies. These AGNs are mainly complied from the RXTE All Sky Survey (XSS), and complemented by the released INTEGRAL AGN catalog. The black hole masses, bolometric luminosities of AGN, and Eddington ratios are derived from their optical spectra in terms of the broad H$\\beta$ emission line. The tight correlation between the hard X-ray (3-20keV) and bolometric/line luminosity is well identified in our sample. Also identified is a strong inverse Baldwin relationship of the H$\\beta$ emission line. In addition, all these hard X-ray AGNs are biased toward luminous objects with high Eddington ratio (mostly between 0.01 to 0.1) and low column density ($<10^{22} \\mathrm{cm^{-2}}$), which is most likely due to the ...

2008-01-01

185

Thickness measurement of Sn-Ag hot dip coatings on Large Hadron Collider Superconducting strands by coulometry  

CERN Document Server

Amperostatic coulometry was applied for the thickness measurement of Sn-Ag hot dip coatings, which comprise an extended Sn-Cu interdiffusion layer. Complementary measurements, notably weight loss, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray fluorescence (XRF), and dynamic secondary ion mass spectroscopy were performed in order to obtain a better interpretation of the coulometry results. Based on the experimental results presented in this article, the three potential changes observed during coulometry measurements are ascribed to (i) the entire dissolution of pure Sn, (ii) the formation of a CuCl salt layer, and (iii) the surface passivation. The measurement of the pure Sn mass is well reproducible despite strong coating thickness variations detected by XRF. Several experimental problems, in particular, a coating undercutting, hamper the determination of the Sn mass in ...

2004-01-01

186

How epitaxial are Pd/sub 2/Si-Si interfaces  

Energy Technology Data Exchange (ETDEWEB)

Pd/sub 2/Si layers produced by evaporation or sputtering onto silicon substrates were examined by high resolution electron microscopy, microdiffraction, X-ray, energy loss and Auger spectroscopy. The Si-Pd/sub 2/Si interfaces produced by evaporation were in all cases rougher and more polycrystalline than those produced by sputtering. X-ray microanalysis showed the predictable variation in palladium distribution across the interface but quantification did not produce the expected palladium-to-silicon ratios, primarily because of probe broadening and X-ray-induced fluorescence. Energy loss spectra showed plasmon energy shifts and changes in Si L edge shape due to bond formation with palladium. Auger data provided evidence for a small amount of oxygen at the Si-Pd/sub 2/Si interface. Electrical measurements of the ideality factor for Schottky barriers made from the materials produced higher values for the ...

1983-06-17

187

Application of radionuclide X-ray fluorescence analysis to the monitoring of the quality of air  

International Nuclear Information System (INIS)

An X-ray fluorometric train was set up for analyzing gravitational fallout, and tested on standard reference samples of fly ashes from conventional power plants. Analysis of thin layers proved inappropriate, and therefore pelletization of the samples, either alone or together with the X-ray MIX binder, was applied. Sample grinding in an agate mortar was found sufficient to suppress the particle size effect. The optimum pressure was 20 MPa. The optimum geometry was sought for "1"0"9Cd source, and limits of detection of 2.78-0.47 #mu#g were achieved for Cr-Zr elements. Tominaga's method was employed for matrix effect correction. Ti, Fe, Cu, Zn, As, Rb, Sr, Zr and Pb were determined in the SRM's; the relative errors ranged from units per cent (for Zn, Rb, Sr and Zr present in concentrations about 100 ppm and for Fe in concentrations of units per cent) up to 45% (for Ti present in a concentration of 0.67%). The method developed was applied to the ...

1990-10-01

188

Operation of beam line facilities for real-time x-ray studies at Sector 7 of the advanced photon source. Final Report  

Energy Technology Data Exchange (ETDEWEB)

This Final Report documents the research accomplishments achieved in the first phase of operations of a new Advanced Photon Source beam line (7-ID MHATT-CAT) dedicated to real-time x-ray studies. The period covered by this report covers the establishment of a world-class facility for time-dependent x-ray studies of materials. During this period many new and innovative research programs were initiated at Sector 7 with support of this grant, most notably using a combination of ultrafast lasers and pulsed synchrotron radiation. This work initiated a new frontier of materials research: namely, the study of the dynamics of materials under extreme conditions of high intensity impulsive laser irradiation.

2003-09-10

189

Association of brain cancer with dental x-rays and occupation in Missouri  

International Nuclear Information System (INIS)

This investigation of a brain cancer cluster in Missouri used two approaches to investigate associations with potential risk factors. In a case-control study in a rural town, we interviewed surrogates of cases and controls about potential risk factors. We found a statistically significant positive association of brain cancer with reported exposure to dental x-rays. Occupation was not associated with the cluster in the rural town. In a standardized proportional mortality study for the state of Missouri, we calculated the observed and expected proportion of brain cancers by occupation and industry in Missouri decedents. We found that motor vehicle manufacturers, beauty shop workers, managers and administrators, elementary school teachers, and hairdressers and cosmetologists had significantly elevated proportions of brain cancer. Brain tumors are inconsistently associated with occupation in the literature. Further ...

1991-01-01

190

Energy Dispersive X-ray Analysis in the Electron Microscope  

CERN Document Server

Energy Dispersive X-ray Analysis in the Electron Microscope

2003-01-01

191

Studies of L x-rays from 64 MeV iodine projectiles in collision with gas targets  

International Nuclear Information System (INIS)

We have studied L x-rays from 64 MeV iodine projectile in collision with various gas targets, Z_2 #18, do not arise from selective M subshell vacancy population, has been conclusively established by the observations by Datz et al (1971) and by Saha et al (1996) that the measured intensity ratio of the Ll and L#alpha# lines, which arise because of transitions from different M subshells into the same L, subshell, does not show any periodic behaviour with Z, but stays rather constant. Differences in the measured L#beta#_1/L#alpha# intensity ratio of iodine with 7"+ and 24"+ charge states impinging on Kr target established the minor role of the electrons in the N shell of the projectile in the x-ray production mechanism. (author)

1997-11-17

192

Radioanalytical determination of chromium in welding fumes  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis and fast neutron activation analysis were used for the determination of chromium. The excitation source for X-ray fluorescence analysis was a ring-shaped "2"4"1Am source with an activity of 18.5x10"9 Bq. SYNPOR filters of 35 mm in diameter were used for the measurement. The 5.414 keV Cr peak was measured with a Si(Li) detector. The sensitivity was 0.05 mg for a period of measurement of 1000 s. A neutron generator with an emission of 10"9 s"-"1 was used as the source of fast neutrons. "5"2V and "5"3V, the products of nuclear reaction with Cr, were measured gamma spectrometrically with a Ge(Li) detector. The sensitivity for Cr is 0.015 mg, in the presence of Mn which causes interference the sensitivity is a mere 0.075 mg. The mentioned methods were used to determine total Cr and Cr(VI) in welding aerosols. It was found that the most toxic form, i.e., Cr(VI), is ...

1985-01-01

193

Radiation methods in research of ancient monuments  

Energy Technology Data Exchange (ETDEWEB)

A 'Laboratory of Quantitative Methods in Monument Research' is being built at the CTU Prague. Its primary orientation is the investigation of historic architecture, although other objects of art can also be investigated. In the first phase, two radiation methods are being established, but it is set up in such a way, that various other methods can readily be added in its future development. The radiation methods chosen for the initial development of the laboratory are: thermoluminescence dating and X-ray fluorescence analysis. The design of the automated TL-reader, built in our laboratories, is adjusted for the purpose of dating of historic brick architecture (which, of course, does not exclude applications for ceramics and other materials). The investigation of renaissance architecture in southern Bohemia and Moravia is under preparation as the first large campaign of this kind in the Czech Republic. Radionuclide ...

2000-11-15

194

Radiation methods in research of ancient monuments  

International Nuclear Information System (INIS)

A 'Laboratory of Quantitative Methods in Monument Research' is being built at the CTU Prague. Its primary orientation is the investigation of historic architecture, although other objects of art can also be investigated. In the first phase, two radiation methods are being established, but it is set up in such a way, that various other methods can readily be added in its future development. The radiation methods chosen for the initial development of the laboratory are: thermoluminescence dating and X-ray fluorescence analysis. The design of the automated TL-reader, built in our laboratories, is adjusted for the purpose of dating of historic brick architecture (which, of course, does not exclude applications for ceramics and other materials). The investigation of renaissance architecture in southern Bohemia and Moravia is under preparation as the first large campaign of this kind in the Czech Republic. Radionuclide X-ray ...

2000-11-15

195

Measuring head for radionuclide X-ray fluorescence analyzer  

International Nuclear Information System (INIS)

The design of a gaging head for a portable radionuclide X-ray fluorescence analyzer is described. The gaging head is designed as a construction unit system which enables the application of lateral reflexion geometry as well as of coaxial geometry. It is designed so that adjustment from one geometry to the other is labour and time saving. The selection of characteristic radiation is performed by a couple of Ross' differential filters. These filters are prepared by a novel technique developed by our laboratory. The filter exchange is effected by the longitudinal move of the couple of filters encapsulated in a holder. The shift of the filters is controlled by means of a triggering mechanism situated in the body of the gaging head handle. This design makes is possible to handle the gaging head during measurements with one hand. A simple interchange of the absorption filter for the transmissive filter allows the operator to avoid any unwanted shift ...

1976-05-21

196

Measurement of L X-ray fluorescence cross-sections for elements with 45 Z50 using synchrotron radiation at 8keV  

British Library Electronic Table of Contents (United Kingdom)

The L shell fluorescence cross-sections of the elements in range 45Z50 have been determined at 8keV using Synchrotron radiation. The individual L X-ray photons, Ll, La, LbI, LbII, LgI and LgII produced in the target were measured with high resolution Si(Li) detector. The experimental set-up provided a low background by using linearly polarized monoenergetic photon beam, improving the signal-to-noise ratio. The experimental cross-sections obtained in this work were compared with available experimental data from Scofield [1,2] Krause [3,4] and Scofield and Puri et al. [5,6]. These experimental values closely agree with the theoretical values calculated using Scofield and Krause data, except for the case of Lg, where values measured of this work are slighter higher.

2011-01-01

197

Radionuclide X-ray fluorescence analysis with environmental application  

International Nuclear Information System (INIS)

The purpose of this work is to present a comprehensive, instructive analysis of the basis of radionuclide XRFA, to describe methods of sample preparation for environmental analysis and to make the reader more familiar with the procedures, methods and instrumentation of radionuclide XRFA used in this field. This book discusses the use of radionuclide XRFA for solving analytical problems of the environment and information is presented concerning the current state of research and use of radionuclide XRFA in this significant area. The present volume will serve as a basic source of data and also as a laboratory handbook. refs.; figs.; tabs.

1990-01-01

198

Nondestructive testing of metal coating thickness and control of chemical composition using radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The principle is described of a method using low-activity emitters as the primary radiation source for analysis. The selection of the radiation source and the detection methods including the assessment of the applicability of various radiation detectors are discussed. The benefits and the constraints of the method are considered. Practical examples are presented showing the application possibilities of the method for testing the thickness of bearing layers, piston ring coats, lead layers, etc. The possibility is shown of applying the rapid test for the composition of tungsten and chromium alloyed metal materials in testing complex systems. (J.K.).

1974-12-03

199

Multielement XRF-analysis of blood from patients with dilated cardiomyopathy  

International Nuclear Information System (INIS)

Radionuclide x-ray fluorescence analysis was used for the determination of Fe, Zn, Br and Rb levels in whole blood from dilated cardiomyopathy patients and from a control group. The XRF-system consisted of a radionuclide source "1"0"9Cd, a semiconductor Si/Li detector connected to a multichannel analyzer. Fe content in blood of patients was significantly lower than that of the control. Zn content showed no deviation from normal range. Values for Br and Rb in patients highly exceed the range reported for them. (author) 4 tabs.; 9 refs.

1991-03-01

200

Elemental concentration analysis in some plant samples by EDXRF at Trabzon  

International Nuclear Information System (INIS)

The elemental analysis of some plant samples have been carried out in Trabzon region (Turkey) using energy-dispersive X-ray fluorescence (EDXRF) spectrometry. We have analyzed plant samples for nine stations using 1.85 GBq 55Fe radioactive sources. We have found that potassium and calcium within 0.3-1.4% and 0.3-2.8% were present in concentration in plants for every station, respectively. The concentration of Cl and Ti generally changed according to the plant species and the sampling station.

2006-12-01

201

Application of radionuclide X-ray fluorescence analysis in determining lanthanum content in tungsten and in iron by internal standard technique  

Energy Technology Data Exchange (ETDEWEB)

The use of the method is described on powder samples before and after sintering with a La content of up to 1%. For excitation of the K series of La a /sup 241/Am source with an activity of 1.11 GBq was used. The obtained results showed that the method is sufficiently accurate (error 7%) at a short period of measurement (100 s). It gives satisfactory results even in the comparison of the experimental relative count rate and the theoretically calculated value despite the fact that the analytical signal comes from the sample surface.

1983-05-01

202

Application of radionuclide X-ray fluorescence analysis in determining lanthanum content in tungsten and in iron by internal standard technique  

International Nuclear Information System (INIS)

The use of the method is described on powder samples before and after sintering with an La content of up to 1%. For excitation of the K series of La a _2_4_1Am source with an activity of 1.11 GBq was used. The obtained results showed that the method is sufficiently accurate (error 7%) at a short period of measurement (100 s). It gives satisfactory results even in the comparison of the experimental relative count rate and the theoretically calculated value despite the fact that the analytical signal comes from the sample surface. (Ha).

1983-01-01

203

6. Sample preparation for determining pollutants in components of the environment  

International Nuclear Information System (INIS)

Examples are given of reference materials for radionuclide X-ray fluorescence analysis (RXFA) of the environment processed by the National Bureau of Standards and the IAEA. Methods are described used for preparing standard materials for RXFA. For determining air pollutants the sample is prepared by dry or wet mineralization. Water samples have to be preserved prior to analysis. Insoluble components are separated by filtration or centrifugation. Biological materials must be dehydrated and homogenized. Samples of soil, sludges, sediments and solid wastes will sometimes have to be converted into a solution in some cases a leachate will have to be obtained. (ES).

1983-12-01

204

Structures and luminescent properties of new uranyl-based hybrid materials  

International Nuclear Information System (INIS)

Six uranyl coordination compounds, UO_2(OH)(PYCA) (1), UO_2(PYCA)_2(H_2O).2H_2O (2), UO_2(PIC)_2 (3), UO_2(H_2O)_2(NIC)_2 (4), UO_2(OH)(HINIC)(INIC) (5), and UO_2(PYTAC)_2(H_2O)_2 (6) were grown as single crystals via hydrothermal synthesis (PYCA - pyrazine-2-carboxylate, PIC - picolinate, NIC - nicotinate, INIC - iso-nicotinate, and PYTAC - 2-(pyridin-4-yl)thiazole-5-carboxylate) to study their optical properties. All six compounds have been identified via single crystal X-ray diffraction and fully characterized via powder X-ray diffraction, infrared spectroscopy, UV-Vis spectroscopy, and fluorescence spectroscopy. Three of the complexes, 1, 3, and 6, represent new structures, and their synthesis and structural characterization is detailed within. The structures of 2, 4, and 5 have previously been reported in the literature. Coordination polymer 1 crystallizes in the orthorhombic space group Pca21 (a = ...

2011-06-01

205

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

Energy Technology Data Exchange (ETDEWEB)

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

2009-09-01

206

Simulation Studies of the X-Ray Free-Electron Laser Oscillator  

Energy Technology Data Exchange (ETDEWEB)

Simulations of the x-ray free-electron laser (FEL) oscillator are presented that include transverse effects and realistic Bragg crystal properties with the two-dimensional code GINGER. In the present cases considered the radiation divergence is much narrower than the crystal acceptance, and the numerical algorithm can be simplified by ignoring the finite angular bandwidth of the crystal. In this regime GINGER shows that the saturated x-ray pulses have 109 photons and are nearly Fourier-limited with peak powers in excess of 1 MW. Wealso include preliminary results for a four-mirror cavity that can be tuned in wavelength over a few percent, with future plans to incorporate the full transverse response of the Bragg crystals into GINGER to more accurately model this tunable source.

2009-08-14

207

Measurements of K-beta/K-alpha X-ray intensity ratios using VEC beams  

International Nuclear Information System (INIS)

An experiment on the K#beta#/K#alpha# characteristic X-ray intensity ratio in silver was performed at VEC Centre, Calcutta using the #alpha#-beams at energies 40 MeV and 50 MeV employing a Si(Li) detector system on-line. The results show that the K#beta#/K#alpha# X-ray intensity ratio at energies 40 and 50 MeV are 0.215 #+-# 0.006 and 0.216 #+-# 0.006, respectively, which indicates no change with beam energy and in accordance with the earlier reports. The present experiment shows the feasibility of studying the K#beta#/K#alpha# ratios as a function of beam energy in different regions of periodic table. Experiments in elements belonging to the 3d shell and their compounds are suggested to look for the chemical effects and their dependence on #alpha#-energy. (author). 7 refs.

1987-02-03

208

Crystallization and preliminary X-ray studies of a galactose-specific lectin from the seeds of Spatholobus parviflorus  

British Library Electronic Table of Contents (United Kingdom)

A galactose-specific seed lectin was purified from the legume Spatholobus parviflorus and crystallized using the hanging-drop vapour-diffusion technique. Thecrystals belonged to space group P1, with unit-cell parameters a = 60.998, b=60.792, c = 78.179-, = 101.32, = 91.38, = 104.32. X-ray diffraction data were collected under cryoconditions (100-K) to a resolution of 2.04- using a MAR image-plate detector system mounted on a rotating-anode X-ray (Cu-K) generator. Molecular replacement using legume-lectin coordinates as a search model gave a tetrameric structure.

2011-01-01

209

An X-ray photoelectron spectroscopic study of B-N-Ti system  

International Nuclear Information System (INIS)

Composite nitrides (such as BN, TiN) are widely used in various industrial applications because of their extreme wear and corrosion resistance, thermal and electrical properties. in order to obtain composite materials with these optimal properties, it is important to elucidate whether any chemical reactions occur at nitride/metal interfaces, e.g., those involving BN-Ti/TiN. Materials of interest include the deposition by PVD of Ti and TiN on BN substrates. Some of these systems were then subjected to varying degrees of physical and thermal alteration. Detailed X-ray photoelectron spectroscopy (XPS) has therefore been rendered of these interfaces using cross-sectional display and sputter etching. Resulting structural and morphological features have been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Diffusion of the nitridation, oxynitride formation and interfacial growth are of general interest.

1997-04-04

210

Using X-ray Microscopy and Hg L3 XANES to study Hg Binding in the Rhizosphere of Spartina Cordgrass  

UK PubMed Central (United Kingdom)

San Francisco Bay has been contaminated historically by mercury from mine tailings as well as contemporary industrial sources. Native Spartina foliosa and non-native S....Full Text Available

2009-10-01

211

Terminal-differential algorithm for identification of local non homogeneity in article  

International Nuclear Information System (INIS)

Terminal-differential algorithm for identification of local nonhomogeneities in items under control is developed on the basis of measurements of X-ray or gamma-radiation weakening. The algorithm may be applied by developing radiation schemes of nondestructive control, identifying inadmissible inclusions in the object under study

212

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

UK PubMed Central (United Kingdom)

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

2011-03-01

213

Preliminary X-ray crystallographic studies of Bacillus subtilis SpeA protein  

UK PubMed Central (United Kingdom)

The speA gene in Bacillus subtilis encodes arginine decarboxylase, which catalyzes the conversion of arginine to agmatine. Arginine decarboxylase is an important enzyme...Full Text Available

214

Localization of gold in synovial membrane of rheumatoid arthritis treated with sodium aurothiomalate. Studies by electron microscope and electron probe x-ray microanalysis.  

UK PubMed Central (United Kingdom)

The localization of gold in the synovial membrane of rheumatoid arthritis patients treated with sodium aurothiomalate was examined and quantitative analysis of epon-embedded sections was carried out...Full Text Available

1977-06-01

215

Localization and Toxic Effects of Cadmium, Copper, and Uranium in Azolla1  

UK PubMed Central (United Kingdom)

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis....Full Text Available

1988-09-01

216

Determination of Organ Doses During Radiological Examinations and Calculation of Somatically Significant Dose.  

Science.gov (United States)

Examples are used to demonstrate that a shift in the point of emphasis is necessary with regard to radiation hazard in medicinal X-ray diagnosis. The parameters employed in this study to calculate somatic dose (SD) and somatically significant dose (SSD) m...

1980-01-01

217

Cardiovascular magnetic resonance guided electrophysiology studies  

UK PubMed Central (United Kingdom)

Catheter ablation is a first line treatment for many cardiac arrhythmias and is generally performed under x-ray fluoroscopy guidance. However, current techniques for ablating complex arrhythmias such...Full Text Available

218

Programmable radionuclide X-ray fluorescence multi-channel spectrometric analyzer, type 123-1  

International Nuclear Information System (INIS)

The whole equipment consists of three separate portable parts: a detector case, a microprocessor and a graphic TV monitor. Magnetic tape memory and an x-y recorder can be connected for recording the measured spectra. The analyzer contains two built-in exchangeable excitation radionuclides. Fluorescence and scattered radiation is detected using a proportional detector. The detected pulses are analyzed by a 256-channel analyzer and the results are shown on the display. The device may be used in mining laboratories, coal and ore dressing plant control rooms or in mining fields of open cast mines for quick detection of the quality of mined or dressed raw materials. (E.S.). 1 fig.

1988-01-01

219

Provenance study of excavated pottery from Beirut using PIXE cluster analysis  

International Nuclear Information System (INIS)

The study of imported ceramics found in Beirut and suspected to belong to north Syrian products will provide key evidence for the roles in trade of the various postulated centers in northern Syria and northern Lebanon. It is proposed that a comprehensive range of likely north Syrian products imported to Beirut will be chemically analyzed by PIXE (proton induced X-ray emission) in order to characterize, compare and isolate the various regional production centers that supplied the city from the Persian to Byzantine periods. In this work, we were mainly focusing on the characterization of Amrit products, by using 3 MeV proton beam and Al funny filter, as X-ray absorber.

2006-08-01

220

Evidence for excess vacancy defects in the Pd-Si system: positron annihilation, x-ray diffraction and Auger electron spectroscopy study  

Energy Technology Data Exchange (ETDEWEB)

The transformation of Pd/Si to Pd{sub 2}Si/Si is investigated using depth-resolved positron annihilation, x-ray diffraction and Auger electron spectroscopy studies. The observed defect-sensitive positron S-parameter value of 1.022-1.054 indicates the existence of divacancies across the silicide/silicon interface and Si substrate region. Our experimental observation of vacancy defects is consistent with the model proposed for excess vacancy generation across the interface consequent to Si diffusion. (letter to the editor)

2003-11-26

221

Determination of size distribution of Guinier-Preston zones in Al-Ag alloys by small-angle x-ray scattering method  

International Nuclear Information System (INIS)

Small-angle X-ray scattering method recognised to be very useful in the studies of structural problems of materials in homogeneous in nanoscale. Studies by small-angle X-ray scattering on the Al-Ag alloys are presented. The size distributions of spherical Guinier-Person zones were calculated using Vonk's and Glatter's methods. Small-angle X-ray scattering studies were performed on Al-5.0 at.%Ag alloy containing Guinier-Preson zones in the #eta#-state. For this alloy one can assume that scattering particles are of spherical shape, have uniform electron density and scatter independently. Moreover, the size distributions were calculated for Al-1.6 at.%Ag alloy containing Guinier-Preston zones in #epsilon#-state (scattering particles with not uniform electron density). Both, Vonk's and Glatter's, methods gave similar size distributions. Profiles of size ...

2001-09-23

222

Computed radiography in X-ray examination of stomach. Evaluation by phantom experiments and clinical studies  

Energy Technology Data Exchange (ETDEWEB)

The usefulness and clinical applicability of computed radiography(FCR) in X-ray examination of the stomach were evaluated in comparison with film-screen (FS) radiography by both phantom experiments and clinical studies. Receiver operating characteristic (ROC) curve analysis consisting of 25 normal and 25 artificially created simulated lesions on an orginally created Styrofoam phantom showed no difference in lesion detectability between FCR and FS radiography. Both were also equal in evaluation of the internal structure and margin of the 25 lesions by visual ranking. ROC curve analysis of clinical cases was performed in 30 cases, 20 normal and 10 abnormal, while evaluation by visual ranking was performed on 18 lesions. There was no significant difference between FCR and FS radiography either with ROC curve analysis or visual ranking, although the variations were somewhat greater in the clinical cases than in the phantom ...

1995-08-01

223

Computed radiography in X-ray examination of stomach. Evaluation by phantom experiments and clinical studies  

International Nuclear Information System (INIS)

The usefulness and clinical applicability of computed radiography(FCR) in X-ray examination of the stomach were evaluated in comparison with film-screen (FS) radiography by both phantom experiments and clinical studies. Receiver operating characteristic (ROC) curve analysis consisting of 25 normal and 25 artificially created simulated lesions on an orginally created Styrofoam phantom showed no difference in lesion detectability between FCR and FS radiography. Both were also equal in evaluation of the internal structure and margin of the 25 lesions by visual ranking. ROC curve analysis of clinical cases was performed in 30 cases, 20 normal and 10 abnormal, while evaluation by visual ranking was performed on 18 lesions. There was no significant difference between FCR and FS radiography either with ROC curve analysis or visual ranking, although the variations were somewhat greater in the clinical cases than in the phantom ...

1995-01-01

224

Structural transformations in heat-resistant protective coatings on nickel alloys  

Energy Technology Data Exchange (ETDEWEB)

In this work a comprehensive metallophysical study was carried out for two aluminosilicide slip coatings of the systems Al-Si and Al-Nb-Si and an electron-beam Co-Cr-Al-Y coating on alloy EP-539 (17...19% Cr, 4...6% Co, 2.5...4% W, 4.5...6.5% Mo, 2...3% Ti, 3...4% Al, 1.4...2% Nb, balance Ni) after high-temperature testing. The protective properties of the coatings were evaluated from the results of laboratory tests for heat resistance at 1000/sup 0/C in the combustion products of diesel fuel with added sulfur at 970, 1000, and 1060/sup 0/C for 100 h and after full-scale tests for 150, 250, 400, and 700 h. Metallographic, hardness, x-ray, and micro x-ray studies of the coating were carried out. Layer-by-layer phase composition and the lattice spacing of the main phases were determined. X-ray analysis was carried out in an a DRON-1 diffractometer in copper K/sub ...

1987-09-01

225

X-ray observation of a. sqrt. 3 x. sqrt. 3 superlattice in KC/sub 8/ at high pressure  

Energy Technology Data Exchange (ETDEWEB)

A single-crystal x-ray study under pressure reveals a phase transition from an in-plane 2x2 commensurate potassium superstructure to a new ..sqrt..3x..sqrt..3 commensurate superstructure. This is the first such transition to be observed; it is related to the recently discovered staging transition of KC/sub 8/ under pressure. In addition this staging transition was observed to occur more slowly and at much lower pressures than in the reported neutron-scattering experiment on highly oriented pyrolytic graphite samples. 13 references, 2 figures.

1985-05-15

226

The use of lead isotopic abundances in trace uranium samples for nuclear forensics analysis  

International Nuclear Information System (INIS)

Secondary ion mass spectrometry (SIMS), secondary electron microscopy (SEM) and X-ray analysis have been applied to the measurement of U-bearing particles with the intent of gleaning information concerning their history and/or origin. The lead isotopic abundances are definitive indicators that U-bearing particles have come from an ore-body, even if they have undergone chemical processing. SEM images and X-ray analysis can add further information to the study that may allude to the extent of chemical processing. The presence of 'common' lead that does not exhibit a radiogenic signature is clear evidence of anthropogenic origin. (author)

2010-06-01

227

Structural, Vibrational and Mechanical Studies of Hydroxyapatite produced by wet-chemical methods  

CERN Document Server

Hydroxyapatite samples were produced by two different wet-chemical methods, and characterized by x-ray diffraction, infrared and compression strength measurements. The x-ray diffraction measurements were simulated using the Rietveld method, and structural data as lattice parameters and average crystallite size were obtained. The infrared spectra showed the presence of CO$_3^{2-}$ ions in all samples, indicating a contamination by these ions. By mixing samples produced by both methods, a bioceramic was obtained and, after sintering, samples with very high compression strengths (26--30 MPa) were obtained.

2004-01-01

228

Radiodiagnosis of Ewing's sarcoma of the rib in children  

International Nuclear Information System (INIS)

The results of the examination of 23 children with Ewing's sarcoma of the rib were analyzed: panoramic chest X-rays in 4 projections, spot radiographs of the robs, superexposed pictures, laterograms, urography, angiography, computerized tomography, and scanning of the skeleton. Causes of diagnostic errors made at the first consultation by a physician, were identified. Peculiarities of X-ray signs of tumors of this site in children were studied. Diagnostic difficulties in tumors complicated by pleurisy and in tumors of small sizes with extrapleural growth were shown. Inclusions in the extraoseous tumor component were noted in 8.7% of the cases.

229

Nanostructure of thin gold films investigated by means of atomic force microscopy and X-ray reflectometry methods  

International Nuclear Information System (INIS)

A study of the thin gold film growth, during the deposition on glass substrate under UHV conditions at low temperatures, is presented. The complementary methods, the atomic force microscopy and grazing incidence x-ray reflectometry, are used for the research. It is shown that due to variation of the time of deposition from 2 to 50 min different kinds of thin Au films nanostructures are obtained: from discontinuous films consisting of isolated islands, via formation of the chains of islands, up to continuous films. (author)

2001-09-23

230

Differential anomalous-x-ray-scattering study of icosahedral and amorphous Pd/sub 58.8/U/sub 20.6/Si/sub 20.6/  

International Nuclear Information System (INIS)

The total and differential atomic pair-correlation functions of an icosahedral (quasicrystalline) solid were determined for the first time, directly by the differential anomalous-x-ray-scattering technique using synchrotron radiation. The observed atomic distances involving uranium atoms in icosahedral Pd/sub 58.8/U/sub 20.6/Si/sub 20.6/ suggest the presence of a quasicrystalline sublattice with vertex decoration. The pair distribution functions in the icosahedral and amorphous phases are similar up to the second-nearest neighbors, or up to 6 A-circle.

231

Differential anomalous-x-ray-scattering study of icosahedral and amorphous Pd/sub 58. 8/U/sub 20. 6/Si/sub 20. 6/  

Energy Technology Data Exchange (ETDEWEB)

The total and differential atomic pair-correlation functions of an icosahedral (quasicrystalline) solid were determined for the first time, directly by the differential anomalous-x-ray-scattering technique using synchrotron radiation. The observed atomic distances involving uranium atoms in icosahedral Pd/sub 58.8/U/sub 20.6/Si/sub 20.6/ suggest the presence of a quasicrystalline sublattice with vertex decoration. The pair distribution functions in the icosahedral and amorphous phases are similar up to the second-nearest neighbors, or up to 6 A-circle.

1986-07-07

232

Application of 10 GeV electron driven x-ray laser in gamma-ray laser research  

Energy Technology Data Exchange (ETDEWEB)

The proposed short wavelength coherent light source driven by the SLAC 3 km linac might be used to induce transitions between nuclear isomeric states. If an isotope were found with energetically adjacent isomeric states, one short-lived and one long-lived, and it were possible to separate and concentrate the long-lived species, and other nuclear and solid-state parameters were favorable, it might be possible to convert sufficient population to the short-lived state to realize [gamma]-ray lasing. Even if the x-ray intensity were insufficient, study of such driven transitions would be quite valuable.

1992-01-01

233

Application of 10 GeV electron driven x-ray laser in gamma-ray laser research  

Energy Technology Data Exchange (ETDEWEB)

The proposed short wavelength coherent light source driven by the SLAC 3 km linac might be used to induce transitions between nuclear isomeric states. If an isotope were found with energetically adjacent isomeric states, one short-lived and one long-lived, and it were possible to separate and concentrate the long-lived species, and other nuclear and solid-state parameters were favorable, it might be possible to convert sufficient population to the short-lived state to realize {gamma}-ray lasing. Even if the x-ray intensity were insufficient, study of such driven transitions would be quite valuable.

1992-12-01

234

Observation of Fluorescence for some lanthanides in LiCl-KCl molten salt media at high temperature  

Energy Technology Data Exchange (ETDEWEB)

To our knowledge, the fluorescence studies of lanthanides in LiCl-KCl eutectic molten salt at a high temperature are not reported yet. The fluorescence of the lanthanide-ions was generally decreased when the temperature was increased. Moreover, the fluorescence of the lanthanides was strong when the sample was solidified to or from the melt. The temperature, where the fluorescence was decreased, was identified to be different depending on the species of the lanthanides and the substrates was considered to possibly be from quenching of the fluorescence due to either the collisions of melted samples induced by high temperature media or the re-absorption of fluorescence by the samples. Several comparison experiments were performed to explain and understand this phenomenon and improve the fluorescence. In this way, an ...

2008-08-15

235

Valence-electron configuration of Ti and Ni in TixNi1-x alloys from Kbeta-to-Kalpha X-ray intensity ratio studies.  

Science.gov (United States)

Kbeta-to-Kalpha X-ray intensity ratios of Ti and Ni have been measured in pure metals and in alloys of Ti(x)Ni(1-x) (x=0.7, 0.6, 0.5, 0.4 and 0.3) following excitation by 22.69 keV X-rays from a 10 mCi (109)Cd radioactive point source. The valence-electron configurations of these metals were determined by corporation of measured Kbeta-to-Kalpha X-ray intensity ratios with the results of multiconfiguration Dirac-Fock calculation for various valence-electron configurations. Valence-electron configurations of 3d-transition metals in alloys indicate significant differences with respect to the pure metals. Our analysis indicates that these differences arise from delocalization and/or charge transfer phenomena in alloys. Namely, the observed change of the valence-electron configurations of metals in alloys can be explained with the transfer of 3d electrons from one element to the other element and/or the rearrangement of ...

2010-01-28

236

Valence-electron configuration of Ti and Ni in TixNi1-x alloys from K?-to-K? X-ray intensity ratio studies  

International Nuclear Information System (INIS)

K?-to-K? X-ray intensity ratios of Ti and Ni have been measured in pure metals and in alloys of TixNi1-x (x=0.7, 0.6, 0.5, 0.4 and 0.3) following excitation by 22.69 keV X-rays from a 10 mCi 109Cd radioactive point source. The valence-electron configurations of these metals were determined by corporation of measured K?-to-K? X-ray intensity ratios with the results of multiconfiguration Dirac-Fock calculation for various valence-electron configurations. Valence-electron configurations of 3d-transition metals in alloys indicate significant differences with respect to the pure metals. Our analysis indicates that these differences arise from delocalization and/or charge transfer phenomena in alloys. Namely, the observed change of the valence-electron configurations of metals in alloys can be explained with the transfer of 3d electrons from one element to the other element and/or the rearrangement of electrons between 3d and 4s, ...

2010-06-01

237

Study of chest portable radiography using computed radiography. Removal effect of X-ray scatter by a copper plate  

Energy Technology Data Exchange (ETDEWEB)

When chest radiographs are obtained using an anti-scatter grid in a mobile x-ray unit by Fuji Computed Radiography (FCR), right lung densities may differ from left lung densities owing to misalignment caused by an oblique x-ray beam. Such misalignment is considered to be caused by factors such as the shape of the bed and angle of the x-ray tube. Misalignment is especially frequent when exposure is carried out in the sitting position. Although a low-ratio grid has been reported to offer improvement, the misalignment is not completely eliminated. Therefore, we used a copper plate without a lattice feature instead of grid, and examined the results. The copper plate was found to have the ability of a grid to eliminate radiation scatter, and, furthermore, to offer the physical capabilities of a grid as determined by Carlin's new grid assessment method. Image quality was demonstrated through contrast manipulation to be ...

2001-04-01

238

Study of chest portable radiography using computed radiography. Removal effect of X-ray scatter by a copper plate  

International Nuclear Information System (INIS)

When chest radiographs are obtained using an anti-scatter grid in a mobile x-ray unit by Fuji Computed Radiography (FCR), right lung densities may differ from left lung densities owing to misalignment caused by an oblique x-ray beam. Such misalignment is considered to be caused by factors such as the shape of the bed and angle of the x-ray tube. Misalignment is especially frequent when exposure is carried out in the sitting position. Although a low-ratio grid has been reported to offer improvement, the misalignment is not completely eliminated. Therefore, we used a copper plate without a lattice feature instead of grid, and examined the results. The copper plate was found to have the ability of a grid to eliminate radiation scatter, and, furthermore, to offer the physical capabilities of a grid as determined by Carlin's new grid assessment method. Image quality was demonstrated through contrast manipulation to be equal to ...

2001-04-01

239

Interaction of x-rays and food pyrolysis products in producing oncogenic transformation in vitro  

International Nuclear Information System (INIS)

In recent years it has become evident from epidemiological and experimental data that a large number of environmental factors, including diet, play a role in modifying the incidence of cancer. Cell culture systems in which oncogenic transformation serves as an end point are powerful tools for evaluating these questions. Using such systems it has been shown recently that pyrolysis products from charred surfaces of broiled meat and fish can transform hamster embryo cells in vitro as well as produce tumors in the animal. Our studies in vitro have demonstrated the oncogenic potential of ionizing radiation in both hamster and human cells and have established in hamster cells the dose response relationship at doses ranging from 1 to 600 rad for x-rays and 0.1 to 150 rad for neutrons. The present work was aimed at evaluating whether there exists a cocarcinogenic interaction between a pyrolysis product and x-rays in their ability ...

1981-07-01

240

A convolution/superposition method using primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance: comparison of calculated and measured 10-MV X-ray doses in thorax-like phantoms  

British Library Electronic Table of Contents (United Kingdom)

We performed experimental studies on the convolution/superposition method reported in the former companion paper (Iwasaki in Radiol Phys Technol 4, 2011) using 10-MV X-ray beams from open-jaw-collimated fields. The method uses primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance. We made a comparison of calculations and measurements in water phantoms and thorax-like phantoms with respect to percentage depth dose curves, tissue???phantom ratio curves, and dose profiles. We made the dose calculation by taking into account the beam-hardening effect with depth and the off-axis radiation-softening effect. We found that the method could be used, in general, for performing accurate dose calculations.

2011-01-01

241

Study of X-ray filter and peak kilovoltage in Fuji computed radiography in regard to the detection of simulated pulmonary nodules  

Energy Technology Data Exchange (ETDEWEB)

To determine a suitable combination of X-ray filter and tube kilovoltage for Fuji Computed Radiography (FCR), provide better detection of pulmonary nodules, and reduce patient exposure, we compared observer performance with different X-ray filters and tube voltages. Radiographs were obtained with a copper filter backed by aluminium, with a tungsten filter backed by yttrium and aluminium, and with a lead filter backed by yttrium and aluminium, at both 100 kVp and 135 kVp. Observer performance in detecting simulated lung nodules, which were placed on the posterior aspect of a chest phantom, was compared using receiver operating characteristic (ROC) techniques for each combination of the X-ray filter and tube voltage. The results of the study indicated that (1) nodule detection was superior for the images obtained with 135 kVq as compared with 100 kVp; (2) approximately equal detection rates were obtained ...

1994-10-01

242

Study of X-ray filter and peak kilovoltage in Fuji computed radiography in regard to the detection of simulated pulmonary nodules  

International Nuclear Information System (INIS)

To determine a suitable combination of X-ray filter and tube kilovoltage for Fuji Computed Radiography (FCR), provide better detection of pulmonary nodules, and reduce patient exposure, we compared observer performance with different X-ray filters and tube voltages. Radiographs were obtained with a copper filter backed by aluminium, with a tungsten filter backed by yttrium and aluminium, and with a lead filter backed by yttrium and aluminium, at both 100 kVp and 135 kVp. Observer performance in detecting simulated lung nodules, which were placed on the posterior aspect of a chest phantom, was compared using receiver operating characteristic (ROC) techniques for each combination of the X-ray filter and tube voltage. The results of the study indicated that 1) nodule detection was superior for the images obtained with 135 kVq as compared with 100 kVp; 2) approximately equal detection rates were obtained ...

1994-01-01

243

Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization  

Energy Technology Data Exchange (ETDEWEB)

The measurements of the L X-ray intensity ratio I(L{alpha})/I(L{beta}), I(L{alpha})/I(L{gamma}), I(L{alpha})/I(L{iota}), I(L{beta})/I(L{gamma}) and I(L{iota})/I(L{gamma}) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV {gamma}-rays from a filtered radioisotope {sup 241}Am was used, and by the radioactive decay of {sup 160}Tb, {sup 160}Er, {sup 173}Lu, {sup 182}Re, {sup 201}Tl, {sup 203}Pb and {sup 207}Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L{alpha}/L{beta}), I(L{alpha}/L{gamma}), I(L{alpha}/L{iota}), I(L{beta}/L{gamma}) and I(L{iota}/L{gamma}) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional ...

2008-05-22

244

Crystal structure of ABPO{sub 5} and optical study of Pr{sup 3+} embedded in these compounds  

Energy Technology Data Exchange (ETDEWEB)

The crystal structure of borophosphates ABPO{sub 5} (A = alkaline earth or Pb) was resolved on a polycrystalline sample using the Rietveld method. The x-ray diffraction patterns data show that ABPO{sub 5} crystallize in a centrosymmetric space group P3{sub 1}21 and their structure is related to the borogermanates REBGeO{sub 5} with a stillwellite-type structure. Pr{sup 3+} ion was used as a local structural probe to corroborate the structural resolution results. Absorption and fluorescence spectra of A{sub 1-x}Pr{sub x}BP{sub 1-x}Ge{sub x}O{sub 5} (A alkaline earth or Pb; x = 0.05) have been investigated at different temperatures. At 9 K the 3{sup H}{sub 4}{yields}{sup 3}P{sub 0} transition of trivalent praseodymium ion (4f{sup 2} configuration) is observed as a single line. This indicates a unique crystallographic site for the rare earth ion in these compounds replacing the divalent cation. Energy level schemes were deduced from the ...

2001-10-22

245

Crystal structure of ABPO_5 and optical study of Pr"3"+ embedded in these compounds  

International Nuclear Information System (INIS)

The crystal structure of borophosphates ABPO_5 (A = alkaline earth or Pb) was resolved on a polycrystalline sample using the Rietveld method. The x-ray diffraction patterns data show that ABPO_5 crystallize in a centrosymmetric space group P3_121 and their structure is related to the borogermanates REBGeO_5 with a stillwellite-type structure. Pr"3"+ ion was used as a local structural probe to corroborate the structural resolution results. Absorption and fluorescence spectra of A_1_-_xPr_xBP_1_-_xGe_xO_5 (A alkaline earth or Pb; x = 0.05) have been investigated at different temperatures. At 9 K the 3"H_4#->#"3P_0 transition of trivalent praseodymium ion (4f"2 configuration) is observed as a single line. This indicates a unique crystallographic site for the rare earth ion in these compounds replacing the divalent cation. Energy level schemes were deduced from the low-temperature spectroscopic measurements. Comparing the electronic level ...

2001-10-22

246

An X-ray source population study of the Andromeda galaxy M 31  

CERN Document Server

XMM-Newton EPIC observations reveal the population of X-ray sources of the bright Local Group spiral galaxy M 31, a low-star-formation-rate galaxy like the Milky Way, down to a 0.2-4.5 keV luminosity of 4.4E34 erg/s. With the help of X-ray hardness ratios and optical and radio information different source classes can be distinguished. The survey detected 856 sources in an area of 1.24 square degrees. Sources within M 31 are 44 supernova remnants (SNR) and candidates, 18 super-soft sources (SSS), 16 X-ray binaries (XRBs) and candidates, as well as 37 globular cluster sources (GlC) and candidates, i.e. most likely low mass XRBs within the GlC. 567 hard sources may either be XRBs or Crab-like SNRs in M 31 or background AGN. 22 sources are new SNR candidates in M 31 based on X-ray selection criteria. Time variability information can be used to improve the source classification. Two GlC sources show type I ...

2005-01-01

247

Radiation 2006. In association with the Polymer Division, Royal Australian Chemical Institute. Incorporating the 21st AINSE Radiation Chemistry Conference and the 18th Radiation Biology Conference, conference handbook  

International Nuclear Information System (INIS)

Full text: The general population is daily exposed to chronic, low doses of ionizing radiation (IR) from both natural and artificial sources. The biological consequences of acute, high dose IR exposure can be readily determined; however, the nature and significance of low dose, low dose-rate IR effects are still the subject of debate. Confounding the issue, are the phenomena collectively referred to as the Radiation-induced Bystander Effect (RIBE). The RIBE describes a collection of in vitro observations that suggest the presence of a soluble, transmissible factor(s) released from irradiated cells that can induce a biological response in un-irradiated cells. The induction, nature and magnitude of the RIBE varies between cell culture systems, radiation sources and end-points measured. Efforts to confirm the presence of the RIBE in vivo have been confined to in vivo-like culture systems and limited work with tumour and bone-marrow transplantation models. Validation of the RIBE in vivo ...

2006-01-01

248

In vitro H2AX phosphorylation and micronuclei induction in human fibroblasts across the Bragg curve of a 577MeV/nucleon Fe incident beam  

Energy Technology Data Exchange (ETDEWEB)

The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the only major protection to astronauts from harmful exposure. Unlike low-linear energy transfer (LET) {gamma} or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure, since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak. The Bragg curve does not necessarily represent the biological damage along the particle traversal, and the 'biological Bragg curve' is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. Here we used a unique irradiation geometry to measure the biological response across the Bragg curve in human fibroblasts exposed to 577MeV/nucleon incident Fe ions in vitro. ...

2006-10-15

252

Sampling and analytical methodologies for energy dispersive X-ray fluorescence analysis of airborne particulate matter  

International Nuclear Information System (INIS)

The present document represents an attempt to summarize the most important features of the different forms of ED-XFR as applied to the analysis of airborne particulate matter. It is intended to serve as a set of guidelines for use by participants in the IAEA's own programmes, and other scientists, who are not yet fully experienced in the application of ED-XRF to airborne particulate samples, and who wish either to make a start on using this technique or to improve their existing procedures. The methodologies for sampling described in this document are of rather general applicability. Emphasis is also placed on the sources of errors affecting the sampling of airborne particulate matter. The analytical part of the document describes the different forms of ED-XRF and their potential applications. Spectrum evaluation, a key step in X-ray spectrometry, is covered in depth, including discussion on several calibration and peak fitting techniques and computer programs ...

1986-06-25

253

Radioanalytical methods of rare earth element determination  

International Nuclear Information System (INIS)

Instrumental neutron activation analysis (INAA) and radionuclide X-ray fluorescence analysis (RXFA) were used for the determination of rare earth elements. For INAA, solution obtained by sample decomposition was dripped onto filter paper, enclosed and sealed into a polyethylene foil. The sample was activated in reactor WWR-S over a period of 4 to 6 hours with a neutron fluence of 10"1"3cm"-"2. Gamma radiation measurement was carried out with a planar and a coaxial HP-Ge detector in three decay periods. La, Ce, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Yb and Lu were determined. The advantage of the method is its accuracy and high sensitivity, the disadvantage is the time-consuming analysis. The RXFA method was used as a rapid and operative method for the analysis of loose ore samples, aqueous and organic solutions of rare earth elements. For exciting X-ray radiation, "2"4"1Am was used and the radiation of K-lines was detected with a ...

1989-06-01

254

Noninvasive analysis of skin iron and zinc levels in beta-thalassemia major and intermedia  

Energy Technology Data Exchange (ETDEWEB)

Diagnostic x-ray spectrometry, a method based on x-ray fluorescence analysis, was used for noninvasive determination of iron and zinc in two distinct skin areas, representing predominantly dermal and epidermal tissues, in 56 patients with beta-thalassemia major and intermedia. The mean iron levels in the skin of patients with beta-thalassemia major and intermedia were elevated by greater than 200% and greater than 50%, respectively, compared with control values. The zinc levels of both skin areas examined were within the normal range. The data indicate that the rate and number of blood transfusions, which correlated well with serum ferritin levels (r . 0.8), are not the only factors that determine the amount of iron deposition in the skin (r less than 0.6). Other sources of iron intake contribute to the total iron load in the tissues, particularly in patients who are not given multiple transfusions. The noninvasive ...

1985-01-01

255

Cd speciation in biomass fly ash particles after size separation by centrifugal SPLITT  

Energy Technology Data Exchange (ETDEWEB)

The finest particle size fractions ({le} 25 {mu}m) in four fly ash samples from fluidised bed combustion of three biomass based fuels and a municipal solid waste fuel were size separated using a centrifugal SPLITT fractionation cell. The ashes were separated into different size fractions and the cadmium concentration, partition and speciation in each separated fraction were then investigated in relation to their possible leaching. The fractionation was evaluated by environmental scanning electron microscopy, which also provided indications of the associations between Cd and other main elements on the particles through the use of X-ray fluorescence mapping. The total concentration of Cd in each fraction was determined by AAS analysis which showed different dependence on the ash particle size in the case of biomass or waste fuels. In addition, the speciation of Cd in each fraction, investigated by sequential chemical extractions and ...

2002-08-01

256

The X-ray Ordinance  

International Nuclear Information System (INIS)

The sections and provisions of the X-ray Ordinance of January 8, 1987 are discussed which are of relevance to dental radiology. (DG).

257

Evolution of surface roughness in silicon X-ray mirrors exposed to a low-energy ion beam  

International Nuclear Information System (INIS)

The possibility of smoothening aspherical X-ray mirrors by irradiation of the surface with a low-energy ion beam is investigated. Nanofocusing being the primary application of these mirrors the ion beam conditions must be optimized to achieve a surface roughness of the order of 0.1-0.2 nm. To address this issue a first study was performed on silicon flat substrates etched using ion energies ranging from 400 to 1200 eV. A second study consisted of eroding the silicon surface while varying the ion grazing incidence angle between 10 deg. and 90 deg. for a fixed value of the ion energy. The surface topography of the samples was characterized at various scales using atomic force microscopy (probed area: 1-10 ?m2), interferential optical microscopy (probed area: 1 mm2) and X-ray scattering (probed area: 100 mm2). Finally, a study by AFM of the evolution of the surface finish level of a ...

2010-05-01

258

Elastic properties and structural studies on some zinc-borate glasses derived from ultrasonic, FT-IR and X-ray techniques  

International Nuclear Information System (INIS)

Glasses in the system (1 - x) [29Na2O- 4Al2O3- 67B2O3]- xZnO (0 ? x ? 35 mol%), have been prepared by the melt quenching technique. Elastic properties, X-ray and FT-IR spectroscopic studies have been employed to study the role of ZnO on the structure of the investigated glass system. Elastic properties and Debye temperature have been investigated using sound wave velocity measurements at 4 MHz at room temperature. The results showed that the density increases and the molar volume decreases while both sound velocities and the determined glass transition temperatures decrease with increase in x. X-ray and infrared spectra of the glasses reveal that the borate network consists of diborate units and is affected by the increase in the concentration of ZnO content. These results are interpreted in terms of the decrease in the N4 values (fraction of tetrahedral coordinated boron atoms), and substitution of ...

2009-05-05

259

Microanalytical method development for Fe, Cu and Zn determination in colorectal cancer cells  

British Library Electronic Table of Contents (United Kingdom)

Microanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes. Sample preparation was performed at microscale (115mL sample volume) with 65% nitric aci...

2011-01-01

260

Determining concentration distribution of admixture from count ratemeter response in continuous analyses  

International Nuclear Information System (INIS)

A comparison is made of the response of a count ratemeter and a pulse counter using the mathematical tool of the Z transform. Transform Z is used for the solution of the convolution integral interpreting the analog output of the count ratemeter used for recording characteristic radiation, excited in the moving beam. The comparison of count rates obtained by the count ratemeter during continuous analysis and the pulse counter during discontinuous measurement gave the transfer function of the count ratemeter in the actual range of count rate. Also discussed is the use of the transfer function for localizing concentration changes in the sample. The use of the described method is demonstrated on the determination of the tin content in tungsten using continuous radionuclide X-ray fluorescence analysis. (B.S.).

1983-01-01

261

Application of nuclear analytical methods in determining heavy metals in a welder's working environment  

International Nuclear Information System (INIS)

The problems are discussed of using radionuclide X-ray fluorescence analysis (the most frequently used source is "2"4"1Am) and neutron activation analysis for monitoring the chemical quality of the working environment of a welder. Elements determinable by these methods are listed and the advantages of the methods stated with regard to speed, simplicity and appropriate accuracy of measurement together with commercial availability of the instruments. Welding as a source of harmful substances is assessed by determination of the amount of chromium in aerosols generated by welding austenitic chromium-nickel steels. The described methods allow to obtain a complex image of the chemical nature of welding aerosols and to understand the mechanism of their impact on the human organism. (J.C.).

1986-01-01

262

5. Sampling  

International Nuclear Information System (INIS)

The sampling is described for radionuclide X-ray fluorescence analysis. Aerosols are captured with various filter materials whose properties are summed up in the table. Fine dispersed solid and liquid particles and gaseous admixtures may be captured by bubbling air through a suitable absorption solution. The concentration of small amounts of impurities from large volumes of air is done by adsorbing impurities on surfactants, e.g., activated charcoal, silica gel, etc. Aerosols may be captured using an electrostatic precipitator and aerosol fractions may be separated with a cascade impactor. Water sampling differs by the water source, i.e., ground water, surface water, rain or waste water. Soil samples are taken by probes. (ES).

1983-12-01

263

Optimizing radiotherapy of orbital and paraorbital tumors: intensity-modulated X-ray beams vs. intensity-modulated proton beams  

International Nuclear Information System (INIS)

Purpose: This study presents a dosimetric optimization effort aiming to compare intensity-modulated (IM) X-rays and IM protons in 4 different orbital and paraorbital tumors. These are most challenging targets for standard radiotherapy due to their close relationship with the eyes and related structures. Methods and Materials: A primary orbital lymphoma, an optic nerve meningioma, a sphenoidal ridge meningioma protruding into the orbit, and a pediatric parameningeal paraorbital rhabdomyosarcoma were selected for the purpose of this study. Planning target volumes (PTVs) and organs at risk (OAR) were defined in each patient CT data set for each tumor site. IM X-ray and IM proton three-dimensional treatment plans were implemented. The following total tumor doses were prescribed: 30 Gy for the orbital lymphoma, 54 Gy for both meningiomas, and 50.4 Gy for the rhabdomyosarcoma case. Dose-volume histograms ...

2000-07-01

264

Gamma and X-ray shielding compositions utilizing bauxite - Red Mud regional research laboratory (CSIR), Bhopal, India  

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: The application spectrum of X-ray and Gamma radiation is increasing exponentially in the area of diagnostic, nuclear medicine, food preservation, nuclear power plants and strategic utilities. To prevent the harmful effects of these radiations, shielding materials based on lead metal and its compounds are being used historically, which are toxic in nature. To protect environment it has become necessary to develop non-toxic lead free shielding materials. The use of titanium metal and its compounds as synthetic rock i.e. SYNROC are reported to be very effective non-toxic shielding materials for various applications. Red mud waste generated in aluminum producing industries possesses a unique mineralogical compositions containing fairly high quantity of titanium oxide and iron oxide useful for making non toxic shielding compositions and therefore red mud has been utilized for the first time in the world ...

2007-09-02

265

X-ray absorption spectroscopy, EELS, and full-potential augmented plane wave study of the electronic structure of Ti_2AlC, Ti_2AlN, Nb_2AlC, and (Ti_0_._5Nb_0_._5)_2AlC  

International Nuclear Information System (INIS)

The structural parameters of various Haegg phases (H or M_n_+_1AX_n phases) are studied experimentally by x-ray and electron spectroscopies, x-ray diffraction, and ab initio full potential as well as full mutiple scattering theoretical calculations. Experimentally it was found that the structure of all ternary compounds analyzed herein are relaxed. The values of the lattice parameters and relaxations obtained from ab initio calculations are in excellent agreement with those deduced from the analysis of the experimental data. The bonding scheme has been analyzed and the charge transfer between constituting atoms determined. It is demonstrated that the strength and electrical transport properties in these materials are principally governed by the metallic planes. For the solid solution (Ti_0_._5Nb_0_._5)_2AlC, the most salient result is that the basal planes are corrugated, which could explain the solid solution scattering ...

2005-01-01

266

Synthesis, spectral and X-ray structural studies of a NO donor Schiff base ligand and its Ni(II) complexes  

British Library Electronic Table of Contents (United Kingdom)

The Schiff base ligand, 4-isopropylbenzaldehyde[N-(3-oxo-3,4-dihydro-2-quinoxalinyl)hydrazone] (Ipbh), the 1:1 condensation product of 4-isopropylbenzaldehyde and 2-hydroxy-3-hydrazinoquinoxiline, has been synthesized and characterized by X-ray crystallography. A series of complexes of Ipbh with Nickel(II), viz., [Ni(Ipbh)2]Cl2 (1), [Ni(Ipbh)2]Br2 (2), [Ni(Ipbh)2]I2 (3), [Ni(Ipbh)2(CH3OH)2](NO3)2(CH3OH)2 (4) and [Ni(Ipbh)2ClO4]ClO4 (5) have been synthesized. All the complexes were characterized by elemental analysis, molar conductivity, CHN analysis, spectroscopic studies, magnetic susceptibility measurements and TG/DTA methods. The solid-state structure of the complex 4 was established by single crystal X-ray crystallography. In all the complexes, Ipbh acts as a bidentate NO chelating age...

2011-01-01

267

Study on pyrolysing behavior of NiO-SDC composite particles prepared by spray pyrolysis technique  

Energy Technology Data Exchange (ETDEWEB)

The NiO-samaria doped ceria (SDC) composite powders were prepared by spray pyrolysis technique at temperatures between 400 and 1000 C. The variation of the particle structure was investigated by X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), scanning electron microscope (SEM), and transmission electron microscope (TEM)-energy-dispersive X-ray spectroscopy (EDS). The thermal analysis of raw materials was also carried out. The following facts became clear in this study. Ceria and nickel have been already separated at 400 C. Samaria is amorphous phase below 600 C, and is dissolved in ceria at 600 C or higher. Samaria is distributed uniformly inside the particles before dissolving in ceria. The thermal decomposition temperatures of metal nitrate are: cerium < nickel < samarium. The results of these analyses were explained without contradiction. It was found that it is ...

2007-03-15

268

Long-term effects of prenatal x-ray of human females: reproductive experience  

Energy Technology Data Exchange (ETDEWEB)

A cohort of singleton black human females exposed to diagnostic x-ray in utero and controls matched by parity, hospital of birth and birthdate have been followed to ages 25 to 30 years in Baltimore, Maryland. The search for possible effects of prenatal irradiation has focused on health, growth, development, and reproductive experience of exposed and control women. This paper reports findings related to reproductive experience. From an original data set of 1458 matched exposed-control pairs of women, questionnaire responses were received from 1109 exposed and 1124 control women including 852 each from pairs in which both the exposed and control woman responded. After careful search for alternative explanations of the findings, the authors concluded that females exposed in utero to low doses of x-ray (probably 1 to 5 rads) had significant increases in their rates of early onset of menses, births at age 15 years or less, numbers of living ...

1981-09-01

269

Investigation of #alpha#-sialon formation by high temperature X-ray diffraction  

International Nuclear Information System (INIS)

A technique for following sialon formation in situ by high temperature X-ray diffraction (HT-XRD) was developed. The composition chosen for study was an yttrium #alpha#-sialon with x=0.4. Powder compacts containing silicon nitride, aluminum nitride and yttria powders were pre-sintered at 1350 C and then studied by HT-XRD at temperatures between 1450 and 1580 C and nitrogen pressures of 0.11 MPa. The furnace was made from graphite coated with porous silicon nitride/silicon carbide. The coating prevented silicon carbide formation in the sample up to 1600 C. X-ray diffraction results show the formation of a Y_1_0Al_2Si_3O_1_8N_4 phase at 1350 C, which dissolved to form #alpha#-sialon and other phases at higher temperatures. The amounts of #alpha#-sialon formed are similar to the amounts reported by other authors. An empirical method was used for the calculation of activation energy for the silicon nitride ...

1993-10-04

270

Alloys and oxides on carbon-supported Pt-Sn electrocatalysts for ethanol oxidation  

Energy Technology Data Exchange (ETDEWEB)

This work reports studies of ethanol oxidation on Pt-Sn/C catalysts with nearly the same particle size and identical overall composition having different amounts of oxide and alloyed phases. Results of characterization of physical properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and in situ dispersive X-ray absorption spectroscopy (DXAS) are presented. The variation in the amount of oxide and alloyed phases, promoted by heat treatments in mild temperature conditions, does not produce any significant particle growth. Cyclic voltammetry and oxidation of adsorbed CO in acid medium are used to probe the surface conditions. Data on the electrocatalytic activity towards ethanol oxidation, obtained by potential sweeps and chronoamperometry, are discussed and correlate well with the physical ...

2010-06-01

271

A MODEL OF THE SPECTRAL EVOLUTION OF PULSAR WIND NEBULAE  

International Nuclear Information System (INIS)

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

2010-06-01

272

X-ray photoelectron spectroscopy and x-ray excited Auger spectroscopy studies of manganese thiophosphate intercalated with sodium ions  

Science.gov (United States)

Polycrystalline powders of Na{sub 2x}Mn{sub 1-x}PS{sub 3} have been synthesized from layered MnPS{sub 3} material by successive ion-exchange intercalation of potassium and sodium ions. Their x-ray photoelectron spectroscopy (XPS) and x-ray excited Auger spectroscopy spectra have been measured at room temperature using Mg K{alpha} (1253.6 eV) x-ray source. In particular, the Mn, P, and S 2p and Na 1s and 2p core-level regions and the Na Auger KL{sub 23}L{sub 23} transition have been investigated. All the analyzed XPS core-level spectra display a single-peak structure, suggesting the absence of nonequivalent atoms of Na, Mn, P, and S. The manganese XPS spectrum shows, as observed in MnPS{sub 3} and in its cesium and potassium intercalation compounds, typical shake-up satellites, suggesting that the Mn-S bond is yet mainly ionic in nature. The comparison with the XPS spectra relative to MnPS{sub 3} and its potassium ...

2008-12-15

273

Water structure as a function of temperature from X-ray scatteringexperiments and ab initio molecular dynamics  

Energy Technology Data Exchange (ETDEWEB)

We present high-quality X-ray scattering experiments on pure water taken over a temperature range of 2 to 77 C using a synchrotron beam line at the advanced light source (ALS) at Lawrence Berkeley National Laboratory. The ALS X-ray scattering intensities are qualitatively different in trend of maximum intensity over this temperature range compared to older X-ray experiments. While the common procedure is to report both the intensity curve and radial distribution function(s), the proper extraction of the real-space pair correlation functions from the experimental scattering is very difficult due to uncertainty introduced in the experimental corrections, the proper weighting of OO, OH, and HH contributions, and numerical problems of Fourier transforming truncated data in Q-space. Instead, we consider the direct calculation of X-ray scattering spectra using electron densities derived from density ...

2003-03-01

274

Benzene molecule is destroyed by ultraviolet and soft X-rays in circumstellar environment  

International Nuclear Information System (INIS)

Benzene molecules , present in the proto-planetary nebula CRL 618, are ionized and dissociated by ultraviolet (UV) and X-ray photons originated from the hot central star and by its fast wind. Ionic species and free radicals produced by these processes can lead to the formation of new organic molecules. The aim of this work is to study the photoionization and photodissociation processes of the benzene molecule, using synchrotron radiation and time-of-flight mass spectrometry. Mass spectra were recorded at different energies corresponding to the vacuum UV (21.21 eV) and soft X-ray (282-310 eV) spectral regions. The production of ions from the benzene dissociative photoionization is here quantified, indicating that C_6H_6 is more efficiently fragmented by soft X-ray than UV radiation, where 50% of the ionized benzene molecules survive to UV dissociation while only about 4% resist to C-rays. Partial ion ...

275

Study on the spatial structure of annomuricatin A, a cyclohexapeptide from the seeds of Annona muricata  

British Library Electronic Table of Contents (United Kingdom)

A cyclic hexapeptide, annomuricatin A (the molecular formula: C27H38N6O7), was isolated from the seeds of Annona muricata. The types and sequence of the amino acids were confirmed by X-ray diffraction analysis. The stereochemistry of the title cyclopeptide was clarified by X-ray crystallographic study. The backbone contains two b-turns, one is type I b-turn and the other is type II, which are stabilized by two transannular 41 backbone hydrogen bonds between Ala and Phe. There are intermolecular hydrogen bonds between the cyclopeptide and the solvent molecules which maintained the steady spatial arrangement in crystal.

2007-01-01

276

New NZP-phosphates B{sub 0.5}FeTa(PO{sub 4}){sub 3} (where B - Ca, Sr, Ba)  

Energy Technology Data Exchange (ETDEWEB)

New phosphates with NaZr{sub 2}(PO{sub 4}){sub 3} structure of the B{sub 0.5}FeTa(PO{sub 4}){sub 3}-type (where B-Ca, Sr, Ba) are synthesized and characterized by X-ray diffraction analysis and IR-spectroscopy. The heating behavior of the phosphates is studied using high-temperature X-ray crystallography in the range 15-625 deg. C. The unit-cell parameters, the coefficients of thermal expansion {alpha}{sub a}, {alpha}{sub c} and their thermal expansion anisotropy |{alpha}{sub c} - {alpha}{sub a}| of the phosphates under study are determined and the dependences of these characteristics on the nature of cations are established and analyzed.

2009-05-05

277

Electrical properties and x-ray diffraction of wood and wood plastic composite (WPC)  

Energy Technology Data Exchange (ETDEWEB)

Wood plastic composite (WPC) of kadom, simul, mango and debdaro were prepared with two monomers methylmethacrylate (MMA) and butylmethacrylate (BMA) using high energy ionizing radiation. X-ray diffraction and scanning electron microscope (SEM) studies reveal that significant grafting occurred with wood fiber. Electric properties like resistivity and dielectric constant of both wood and WPC were measured under different moisture contents and relative humidities. The resistivities of wood decreased dramatically with increase of moisture content, but those of WPC decreased very slowly with moisture content. The dielectric constant of wood increased significantly with moisture content but no significant difference was observed in the case of WPC within the range of moisture contents studied. The dielectric constants of untreated wood also increased with their densities. (author).

1991-01-01

278

K and L x-ray production cross sections excited by 14.00--34.16 MeV #alpha#-particle beams  

International Nuclear Information System (INIS)

K and L-shell x-ray production cross sections were measured using #alpha#-particle beams of 14.00 to 34.16 MeV. The K-shell measurements ranged from Z = 20 to Z = 50 and included Ca, Sc, Ti, V, Fe, Ni, Cu, Zn, Ga, Br, Rb, Sr, Y, Mo, Ag, In, and Sn while the L-shell measurements ranged from Z = 55 to Z = 92 and included Cs, Ba, Ce, Gd, Tm, Lu, Au, Pb, Th, and U. Thin metallic foils were used for the measurements and corrections for self-attenuation were negligible. A liquid nitrogen cooled Si(Li) detector and associated pulsed optical electronics were used in detecting x-rays. Absolute cross sections with an uncertainty of +-10 percent are presented for the elements measured. Also smoothed cross sections are presented which were generated by a three term polynomial fit of the experimental data points. By use of available fluorescence yields the K-shell data were converted to ionization cross sections and compared to various ...

279

Depth-profiling of vertical sidewall nanolayers on structured wafers by grazing incidence X-ray flourescence  

Energy Technology Data Exchange (ETDEWEB)

The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, developed an alignment strategy to specify elemental depth profiling in vertical sidewall layers on structured wafers. For this purpose, PTB's irradiation chamber for 200 mm and 300 mm silicon wafers was used to combine total-reflection X-ray fluorescence (TXRF) and grazing incidence XRF (GIXRF) techniques by employing monochromatized undulator radiation of the BESSY II electron storage ring. 3-D test structures were fabricated to develop an optimal alignment strategy allowing for depth profiling in such nanolayers. The test structures consisted of silicon bars with widths/spacings either in the {mu}m or in the nm range. In order to be able to differentiate the sidewalls more easily from the remainder of the structures, they were provided with an additional silicon nitride layer. Four structure types of different bar width and density ...

2008-12-15

280

Depth-profiling of vertical sidewall nanolayers on structured wafers by grazing incidence X-ray flourescence  

International Nuclear Information System (INIS)

The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, developed an alignment strategy to specify elemental depth profiling in vertical sidewall layers on structured wafers. For this purpose, PTB's irradiation chamber for 200 mm and 300 mm silicon wafers was used to combine total-reflection X-ray fluorescence (TXRF) and grazing incidence XRF (GIXRF) techniques by employing monochromatized undulator radiation of the BESSY II electron storage ring. 3-D test structures were fabricated to develop an optimal alignment strategy allowing for depth profiling in such nanolayers. The test structures consisted of silicon bars with widths/spacings either in the ?m or in the nm range. In order to be able to differentiate the sidewalls more easily from the remainder of the structures, they were provided with an additional silicon nitride layer. Four structure types of different bar width and density parameters on two 200 mm ...

2008-12-01

281

Six orders of magnitude dynamic range in capillary electrophoresis with ultrasensitive laser-induced fluorescence detection  

UK PubMed Central (United Kingdom)

An ultrasensitive laser-induced fluorescence detector was used with capillary electrophoresis for the study of 5-carboxy-tetramethylrhodamine. The raw signal from the detector provided roughly...Full Text Available

2009-12-15

282

Upgrade of X-ray Magnetic Diffraction Experimental System and Its Application to Ferromagnetic Material  

International Nuclear Information System (INIS)

We have performed X-ray magnetic diffraction (XMD) experiment of ferromagnets at the Photon Factory (PF) of the High Energy Accelerator Research Organization (KEK) in Tsukuba. In this study, we have upgraded the XMD experimental system in order to apply this method to as many samples as possible. Upgrade was made for (1) the X-ray counting system and related measurement program, (2) the electromagnet, and (3) the refrigerator. The performance of the system was enhanced so that (1) the counting rate capability was improved from 104cps to 105cps, (2) the maximum magnetic field was increased from 0.85T to 2.15T, and (3) the lowest sample temperature was reduced from 15K to 5K. The new system was applied to an orbital ordering compound of YTiO3, and we obtained spin magnetic form factor for the reflection plane (010) perpendicular to the b axis. The magnetic field of 2T was needed to saturate the magnetization of YTiO3 along ...

2007-01-19

283

Previous heat treatment inducing different plasma nitriding behaviors in martensitic stainless steels  

International Nuclear Information System (INIS)

In this work we report a study of the induced changes in structure and corrosion behavior of martensitic stainless steels nitrided by plasma immersion ion implantation (PI"3) at different previous heat treatments. The samples were characterized by x-ray diffraction and glancing angle x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and potentiodynamic measurements. Depending on the proportion of retained austenite in the unimplanted material, different phase transformations are obtained at lower and intermediate temperatures of nitrogen implantation. At higher temperatures, the great mobility of the chromium yields CrN segregations like spots in random distribution, and the #alpha#"'-martensite is degraded to#alpha#-Fe (ferrite). The nitrided layer thickness follows a fairly linear relationship with the temperature and a parabolic law with the process time. The ...

2006-09-01

284

Physico-chemical, optical and electrochemical properties of iron oxide thin films prepared by spray pyrolysis  

International Nuclear Information System (INIS)

Iron oxide thin films were prepared by spray pyrolysis technique onto glass substrates from iron chloride solution. They were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and (UV-vis) spectroscopy. The films deposited at T _s #<=# 450 deg. C were amorphous; while those produced at T _s_u_b = 500 deg. C were polycrystalline #alpha#-Fe_2O_3 with a preferential orientation along the (1 0 4) direction. By observing scanning electron microscopy (SEM), it was seen that iron oxide films were relatively homogeneous uniform and had a good adherence to the glass substrates. The grain size was found (by RX) between 19 and 25 nm. The composition of these films was examined by X-ray photoelectron spectroscopy and electron probe microanalysis (EPMA). These films exhibited also a transmittance value about 80% in the visible and infrared range. The cyclic ...

2006-12-15

285

Future metrology needs for FEL reflective optics.  

Energy Technology Data Exchange (ETDEWEB)

An International Workshop on Metrology for X-ray and Neutron Optics has been held March 16-17, 2000, at the Advanced Photon Source, Argonne National Laboratory, near Chicago, Illinois (USA). The workshop gathered engineers and scientists from both the U.S. and around the world to evaluate metrology instrumentation and methods used to characterize surface figure and finish for long grazing incidence optics used in beamlines at synchrotrons radiation sources. This two-day workshop was motivated by the rapid evolution in the performance of x-ray and neutron sources along with requirements in optics figure and finish. More specifically, the performance of future light sources, such as free-electron laser (FEL)-based x-ray sources, is being pushed to new limits in term of both brilliance and coherence. As a consequence, tolerances on surface figure and finish of the next generation of optics are expected to become tighter. The ...

2000-09-21

286

Extreme Ultraviolet Emission from Abell 4059  

CERN Document Server

We present the results of a search for Extreme Ultraviolet emission in A4059, a cluster with an X-ray emitting cluster gas. Our analysis of Extreme Ultraviolet Explorer (EUVE) Deep Survey observations of this cluster shows that it is associated with diffuse EUV emission. Outside the central 2 arcmin radius the entire EUV emission detected is explained by the low energy tail of the X-ray emitting gas. Within the central 2 arcmin region of the cluster we find a deficit of EUV emission compared to that expected from the X-ray gas. This flux deficit is discussed in the context of the cluster's cooling flow. The results derived for A4059 are compared to EUVE results obtained for other clusters such as Coma, Virgo, A1795, and A2199. As part of the study we have carried out a detailed investigation of the stability of the EUVE Deep Survey detector background. Based on long integrations of blank sky over 27 ...

2000-01-01

287

Comparison of two dose-area-product ionization chambers with different conductive surface coating for over-table and under-table tube configurations  

Energy Technology Data Exchange (ETDEWEB)

A custom-built graphite-coated transmission ionization chamber is compared to the VacuDAP 2001 (VacuTec, Dresden, Germany), which has transparent conductive electrodes. A study was made of the dependence of response on x-ray tube potential for both types of chamber under identical conditions of exposure using over-table and under-table x-ray tubes. Since the calibration factor is the dose-area product of the radiation incident on the patient per chamber reading, it depends on the intrinsic response of the chamber as well as the effect of material in the beam between the x-ray tube and patient. Differences of about 20% were measured between the intrinsic and the over-table calibration factors and between the over-table and the under-table calibration factors for both chambers. The VacuDAP display is specifically calibrated for the over-table condition and would overstate the actual DAP in the under-table ...

2000-03-01

288

Lung studies with spiral CT. pitch 1 versus pitch 2  

International Nuclear Information System (INIS)

In Spiral CT, the pitch is the ratio of the distance to tabletop travels per 360 degrees rotation to nominal slice width, expressed in mm. Performing Spiral CT examination with pitch 2 allows to reduce examination time, exposure and contrast dose, and X-ray tube overload. The authors investigated the yield of pitch 2 in lung parenchyma studies, particular relative to diagnostic image quality.

1999-03-01

289

A study of the effect of Yttria additions on densification of #beta#-sialon  

International Nuclear Information System (INIS)

In this paper the effect of adding commercially pure yttria concentrate and yttrium carbonate concentrate (NUCLEMON) on the densification of #beta#-Sialon has been studied. The specimens were sintered in graphite furnace at 1720 and 175 deg C, for 1 hour in a nitrogen atmosphere. Densities of up to 99% of the theoretical density were obtained. Microstructural analyses of the specimens were carried out with the aid of an X ray diffractometer and a scanning electron microscope. (author)

1995-06-10

290

Zeolite-supported catalysts. Report for August 1986-November 1987  

Energy Technology Data Exchange (ETDEWEB)

The present paper is a comparative study of the cerium-containing nickel catalysts supported on x- and y-zeolites. In general, the addition of cerium ions caused an increase in the catalytic activity for CO hydrogenation and shifted the product selectivity to high molecular weight hydrocarbons. The degree of the effect of cerium additive depends on the ratio of cerium to nickel contents, the reduction temperature, and the nature of the supporting materials. Catalyst characterization, including volumetric hydrogen chemisorption, temperature programmed reduction/desorption, x-ray diffraction, surface area measurements, in-situ infrared spectroscopy and x-ray photoelectron spectroscopy, was performed in order to interpret the phenomena due to the effects of cerium additives and the support effect on Ni/zeolite catalysts.

1988-01-01

291

X-ray studies of solid n-H/sub 2/  

Energy Technology Data Exchange (ETDEWEB)

Results of X-ray investigations of solid normal hydrogen are presented. Temperature dependences of the lattice parameteps, molar volumes, linear and volume expansion coefficients in the 2K-Tsub(melt) temperature range are obtaiped. An essential n-H/sub 2/ expansion anisotropy in the premelting temperature region is pointed out. It is shown that the hexagonal lattice parameter ratios over the whole investigated temperature range is considerably higher than for solid parahydrogen. A considerable difference in thermal expansion of normal hydrogen and parahydrogen in the low temperature region is revealed. It is caused by contribuation of a rotational subsystem, increasing with the temperature decrease to crystal expansion. A detailed analysis of solid n-H/sub 2/ thermodynamic properties is conducted. The data testifying to the presence of isomorphous phase transformation in the solid n-H/sub 2/ in the premelting temperature region are discussed.

1983-08-01

292

X-ray Microdiffraction and Strain Gradient Crystal Plasticity Studies of Geometrically Necessary Dislocations Near a Ni Bicrystal Grain Boundary  

Energy Technology Data Exchange (ETDEWEB)

We compare experimental measurements of inhomogeneous plastic deformation in a Ni bicrystal with crystal-plasticity simulations. Polychromatic X-ray microdiffraction, orientation imaging microscopy and scanning electron microscopy, were used to characterize the geometrically necessary dislocation distribution of the bicrystal after uniaxial tensile deformation. Changes in the local crystallographic orientations within the sample reflect its plastic response during the tensile test. Elastic strain in both grains increases near the grain boundary. Finite element simulations were used to understand the influence of initial grain orientation and structural inhomogeneities on the geometrically-necessary dislocations arrangement and distribution and to understand the underlying materials physics.

2009-01-01

293

Study of the cyclotron feature in MXB 0656-072  

CERN Document Server

We have monitored a Type II outburst of the Be/X-ray binary MXB 0656-072 in a series of pointed RXTE observations during October through December 2003. The source spectrum shows a cyclotron resonance scattering feature at 32.8 +/- 0.5 keV, corresponding to a magnetic field strength of (3.67 +/- 0.06) x 10^12 G and is stable through the outburst and over the pulsar spin phase. The pulsar, with an average pulse period of 160.4 +/- 0.4 s, shows a spin-up of 0.45 s over the duration of the outburst. From optical data, the source distance is estimated to be 3.9 +/- 0.1 kpc and this is used to estimate the X-ray luminosity and a theoretical prediction of the pulsar spin-up during the outburst.

2006-01-01

294

Studies of crystalline CdZnTe radiation detectors and polycrystalline thin film CdTe for X-ray imaging applications  

CERN Document Server

The development of a replacement to the conventional film based X-ray imaging technique is required for many reasons. One possible route for this is the use of a large area film of a suitable semiconductor overlaid on an amorphous silicon readout array. A suitable semiconductor exists in cadmium telluride and its tertiary alloy cadmium zinc telluride. In this thesis the spectroscopic characteristics of commercially available CZT X- and gamma-radiation detectors are established. The electronic, optical, electro-optic, structural and compositional properties of these detectors are then investigated. The attained data is used to infer a greater understanding for the carrier transport in a CZT radiation detector following the interaction of a high energy photon. Following this a method used to fabricate large area films of CdTe on a commercial scale is described. This is cathodic electrodeposition from an aqueous electrolyte. The theory and experimental arrangement for ...

2001-01-01

295

Organ doses received by atomic bomb survivors during radiological examinations at the Radiation Effects Research Foundation  

Energy Technology Data Exchange (ETDEWEB)

When evaluating the risks of oncogenesis and cancer mortality following exposure to the radiations of the atomic bombs (A-bombs), the medical X-ray doses received by the A-bomb survivors must also be estimated and considered. Using a human phantom, dosimetry was performed to estimate the X-ray doses received by A-bomb survivors during medical examinations at the Radiation Effects Foundation (RERF) as part of the long-term follow-up on the Adult Health Study (AHS). These examinations have been estimated to represent nearly 45% of the survivors' cumulative medical irradiation dose. Doses to the salivary glands, thyroid gland, lung, breast, stomach and colon were measured using thermoluminescent dosemeters. The results, which are reported here, will aid in estimating organ doses received by individual AHS participants. (Author).

1991-08-01

296

Organ doses received by atomic bomb survivors during radiological examinations at the Radiation Effects Research Foundation  

International Nuclear Information System (INIS)

When evaluating the risks of oncogenesis and cancer mortality following exposure to the radiations of the atomic bombs (A-bombs), the medical X-ray doses received by the A-bomb survivors must also be estimated and considered. Using a human phantom, dosimetry was performed to estimate the X-ray doses received by A-bomb survivors during medical examinations at the Radiation Effects Foundation (RERF) as part of the long-term follow-up on the Adult Health Study (AHS). These examinations have been estimated to represent nearly 45% of the survivors' cumulative medical irradiation dose. Doses to the salivary glands, thyroid gland, lung, breast, stomach and colon were measured using thermoluminescent dosemeters. The results, which are reported here, will aid in estimating organ doses received by individual AHS participants. (Author).

1991-01-01

297

Neutron star evolution and emission  

Science.gov (United States)

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

1997-08-01

298

Microstructure analysis of nanocrystalline powders by X-ray diffraction  

International Nuclear Information System (INIS)

The use of X-ray diffraction line profile analysis for the study of nanocrystalline powders is described. The fundamentals of the theory are presented in terms of crystallite/domain size, size distribution, lattice distortion, dislocations density and stacking faults. Line profile parameters and the methods of pattern fitting introduced to overcome the diffraction-line overlap problem are discussed. The approaches based of the integral breadth of the measured line profiles and the Fourier method are discussed. In addition, simplified approaches are also commented. Representative examples are selected to illustrate various cases of microstructure, such as nanomaterials with strain-free spherical nano crystallites, strain-free crystallites with anisotropic crystallite shape, anisotropic crystallites with microstrains and spherical crystallites with dislocation densities and crystallite size distributions. (author)

2001-09-23

299

Melatonin exerts differential actions on X-ray radiation-induced apoptosis in normal mice splenocytes and Jurkat leukemia cells  

British Library Electronic Table of Contents (United Kingdom)

Abstract: The ability of melatonin as a potent antioxidant was used as a rationale for testing its antiapoptotic ability in normal cells. Recently, melatonin was shown to possess proapoptotic action by increasing reactive oxygen species in certain cancer cells. The modification of radiation-induced apoptosis by melatonin and the expression of apoptosis-associated upstream regulators were studied in normal mice splenocytes and Jurkat T leukemia cells. C57BL/6 mice were exposed to a single whole body X-ray radiation dose of 2 Gy with or without 250 mg/kg melatonin pretreatment. The Jurkat cells were divided into four groups of control, 1 mm melatonin alone, 4 Gy irradiation-only and melatonin pretreatment before irradiation. The highest level of apoptosis in the normal splenic white pulp was...

2009-01-01

300

Feasibility study of the iterative x-ray phase retrieval algorithm  

International Nuclear Information System (INIS)

An iterative phase retrieval algorithm was previously investigated for in-line x-ray phase imaging. Through detailed theoretical analysis and computer simulations, we now discuss the limitations, robustness, and efficiency of the algorithm. The iterative algorithm was proved robust against imaging noise but sensitive to the variations of several system parameters. It is also efficient in terms of calculation time. It was shown that the algorithm can be applied to phase retrieval based on one phase-contrast image and one attenuation image, or two phase-contrast images; in both cases, the two images can be obtained either by one detector in two exposures, or by two detectors in only one exposure as in the dual-detector scheme.

2009-01-01

301

Effects of Tapered Betafunction in the LCLS Undulators  

Energy Technology Data Exchange (ETDEWEB)

The Linac Coherent Light Source (LCLS) is an X-ray free-electron laser (FEL) project based on the SLAC linac [1]. With its nominal set of electron beam, focusing and undulator parameters, it is designed to achieve SASE saturation at an undulator length of about 100 m with an average power of 10 GW. In order to keep the electron beam focused in the undulators, a FODO lattice is integrated along the entire length of the undulators. Nominally, the quadrupole strengths are chosen to produce nearly constant betafunction and beam size along the undulator, optimized for the FEL interaction in the exponential growth regime. Since these quadrupoles are electromagnetic, it is possible to adjust the individual quadrupole strength to vary the betafunction and the beam size along the undulator, tailoring the FEL interaction in the start-up and the saturation regimes. In this paper, we present simulation studies of the tapered betafunction in the LCLS ...

2005-09-30

302

Corrosion of gold bridgewire in electronic components  

Energy Technology Data Exchange (ETDEWEB)

Accelerated aging tests on gold bridgewired detonator assemblies to determine compatibility of the Au and Pd-In-Sn solder with the organic explosive, PENT, have revealed an unusual corrosion process. These tests, conducted at 74/sup 0/C and 54/sup 0/C indicated a preferential attack of the gold. A matrix of corrosion test units was established to study this corrosion problem with accelerating temperatures up to 100/sup 0/C. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and x-ray diffraction techniques were used to determine the extent of the corrosion and identify the corrosion products. Results indicate the preferential attack of the gold was due to HCN formed by decomposition of the explosive powder (PETN) at high temperatures. Other associated reactions were also observed including subsequent attack of the solder by the gold corrosion product and degradation of the plastic header.

1986-01-01

303

Chemical state analysis of Si-base ceramics sliding materials by EPMA  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the present study is to develop a new method for chemical state analysis by means of EPMA(Electron probe microanalyser). The measured X-ray intensity of Si-K{beta} characteristic X-ray spectra were read-out by a 16 bit microcomputer with a RS-232C interface. And using the curve fitting method the quantitative analysis of chemical compositions in a ternary compound that constituted of the same element has been established. The present method was applied to analyse of the friction and wear properties of Si-base ceramics sliding materials. It was found that the wear debris contains both the compositions of the sliding materials and SiO{sub 2}, and the SiO{sub 2} contents in wear debris was changed with relative humidity. The results clearly showed that the proposed method is very useful for determing the compositions in the ternary compound. (author).

1994-03-01

304

Chemical state analysis of Si-base ceramics sliding materials by EPMA  

International Nuclear Information System (INIS)

The purpose of the present study is to develop a new method for chemical state analysis by means of EPMA(Electron probe microanalyser). The measured X-ray intensity of Si-K#beta# characteristic X-ray spectra were read-out by a 16 bit microcomputer with a RS-232C interface. And using the curve fitting method the quantitative analysis of chemical compositions in a ternary compound that constituted of the same element has been established. The present method was applied to analyse of the friction and wear properties of Si-base ceramics sliding materials. It was found that the wear debris contains both the compositions of the sliding materials and SiO_2, and the SiO_2 contents in wear debris was changed with relative humidity. The results clearly showed that the proposed method is very useful for determing the compositions in the ternary compound. (author).

305

Chemical and morphological characterization of mesoporous material supported copper oxide nanoparticles for potential application  

British Library Electronic Table of Contents (United Kingdom)

SBA-15 supported nano-scaled copper oxide was synthesized by impregnation method via ultrasonic-assisted route. The removal test from gas mixture containing 0.1?vol.% hydrogen sulfide was carried out over this material at atmospheric conditions. The effects of the chemical nature of copper oxide and the textural properties of the material on removal capacity were studied. The materials before and after the removal test were analyzed by nitrogen adsorption, X-ray diffraction, Transmission Electron Microscope, X-ray photoelectron Spectroscopy, Fourier Transform Infrared Spectrometer and Inductive Coupled Plasma. The results showed that copper species are located predominantly in mesopore channels, existing as copper oxide nanoparticles. Mesopores are active sites for removal reaction. The ou...

2011-01-01

306

Beryllium coating on JET Inconel tiles  

International Nuclear Information System (INIS)

Full text: Institute for Nuclear Research, Pitesti-Mioveni, Romania in direct cooperation with the National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest studied and prepared for coating more than 1000 tiles made of Inconel with 7-9 #mu#m of beryllium for nuclear fusion applications at JET, Culham, UK. The principles of manufacturing processes using thermal evaporation and plasma ignited in pure metal vapors as well as by Thermionic Vacuum Arc (TVA) method and the properties of the Ni and Be coatings are presented. The prepared beryllium layers were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and atomic force microscopy. (authors)

2009-10-12

307

Application of CaSO4:Dy (TLD-900) to diagnostic x-ray exposures  

International Nuclear Information System (INIS)

The properties of a new commercial thermoluminescent dosimeter, CaSO4:Dy without a LiF binder (TLD-900) was studied for low-exposure measurements in diagnostic radiology. The former TLD-900 had a LiF binder (herein referred to as ''TLD-900/LiF''). The principle features of this dosimeter are its high sensitivity to low-energy radiation and its relatively low fading which permits measurements down to less than 2.6 X 10(-8) C kg (0.1 mR) with an accuracy better than 20%. The characteristics, annealing procedures, light sensitivity, energy response, reproducibility, and fading, of TLD-900 are discussed and compared with TLD-900/LiF. When the precautions presented in this paper are used, the dosimeters can be used for the measurement of x-ray exposures.

308

A study of reconstruction algorithms and filters for an industrial X-ray tomography system  

Energy Technology Data Exchange (ETDEWEB)

Computed tomography (CT) has been incorporated in an industrial Diode-Array Digital Radiography (DADR) system. An input data size of 512 pixel points x 400 projections yielded a 400x400 output image matrix. Reconstruction algorithms used are the filtered backprojection (FBP) and the direct Fourier reconstruction (DFR). Various filters were used in the FBP reconstruction process and their effects on image quality were evaluated. A spatial resolution of 100 {mu}m was measured with a block of plates and a minimum detectable feature size in the range of 10-100 {mu}m was measured using thin wires. Industrial specimens imaged have included ceramic samples, ball bearings and integrated circuits. A number of engineering problems have been solved, such as adjustment of the X-ray source, centering of the rotator spindle in the view field and beam-hardening corrections. (orig.).

1990-12-20

309

X-ray magnetic circular dichroism measurements using an X-ray phase retarder on the BM25 A-SpLine beamline at the ESRF  

UK PubMed Central (United Kingdom)

Circularly polarized X-rays produced by a diamond X-ray phase retarder of thickness 0.5 mm in the Laue transmission configuration have been used for recording X-ray magnetic circular dichroism...Full Text Available

2010-05-01

310

Pharmaceutics | Special Issue: Molecular Imaging  

Wastenet

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

311

Synthesis of histidine-stabilized cadmium sulfide quantum dots: Study of their fluorescence behaviour in the presence of adenine and guanine  

British Library Electronic Table of Contents (United Kingdom)

Cadmium sulfide particles have been synthesized in the aqueous medium using the amino acid histidine as a stabilizing agent. These particles demonstrate the phenomenon of size quantization effect. The fluorescence of histidine-stabilized CdS was found to be enhanced and quenched by the addition of DNA bases adenine and guanine, respectively. The fluorescence enhancement of CdS in the presence of adenine has been explained on the basis of interaction between the quantum dot stabilizer and the amino group of adenine. Quenching of CdS fluorescence by guanine occurs due to interaction of the substrate with the quantum dot surface.

2010-01-01

312

Development of time-resolved laser fluorescence spectrometry for on-line uranium checking in solutions of the Purex reprocessing process; Developpement de la spectrofluorimetrie laser a resolution temporelle pour le controle en ligne de l`uranium dans les solutions du procede de retraitement purex  

Energy Technology Data Exchange (ETDEWEB)

The Purex process and the fluorescence spectrometry are first recalled, then uranyl fluorescence is studied in a pure nitric medium without other elements to establish a theoretical model, allowing the description of uranium fluorescence signal with a general equation. The influence of different parameters (temperature, inhibitors, dynamic quenching of iron and cerium) is investigated to develop the model. A quantitative analysis method without addition of reagents is proposed to validate the model.

1992-02-25

313

Valence determination in EuM_2X_2 compounds: L_I_I_I-edge versus Moessbauer isomer shift  

International Nuclear Information System (INIS)

A comparative study by Eu-L_I_I_I X-ray absorption and "1"5"1Eu-Moessbauer spectroscopy is presented for the EuPd_2_-_xAu_x Si_2 series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L_I_I_I-edge spectra are discussed.

1986-07-07

314

Valence determination in EuM/sub 2/X/sub 2/ compounds: L/sub III/-edge versus Moessbauer isomer shift  

Energy Technology Data Exchange (ETDEWEB)

A comparative study by Eu-L/sub III/ X-ray absorption and /sup 151/Eu-Moessbauer spectroscopy is presented for the EuPd/sub 2-x/Au/sub x/ Si/sub 2/ series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L/sub II /I-edge spectra are discussed.

1986-12-01

315

Studies of South African medicinal plants: Pt. 2. Caespitin, a new phloroglucinol derivative with antimicrobial properties from Helichrysum caespititium  

Energy Technology Data Exchange (ETDEWEB)

Extracts from Helichrysum caespititium were found to have antimicrobial activity. Structure elucidation of the active compound, 2-(4-methylpentanoyl)-4-(3-methylbuten-2-yl)-phloroglucinol (caespitin), by means of spectroscopic and X-ray crystallographic analyses, is described.

1983-12-01

316

PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk  

Energy Technology Data Exchange (ETDEWEB)

Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

2010-03-15

317

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

International Nuclear Information System (INIS)

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

2001-09-23

318

Nonformity of the electron density in amorphous silicon films  

Energy Technology Data Exchange (ETDEWEB)

The authors study the nonuniformity of a-Si:H films obtained by the method of vacuum condensation, with the help of x-ray small-angle scattering (SLS) and transmission electron microscopy. Films of hydrogenated amorphous silicon are greatest interest, because the electronic properties of this material can be controlled by doping. As a result of the compensation of the ruptured bonds, and possibly, effects of melting, the properties of such films are analogous to those of singlecrystalline silicon. XLS enables a quantitative determination of the prameters of the regions of low electron density (RLD) in such objects.

1985-12-01

319

Multiple imaging radiography at LNLS  

Energy Technology Data Exchange (ETDEWEB)

An analyzer-based X-ray phase-contrast imaging (ABI) setup has been mounted at the Brazilian Synchrotron Light Laboratory (LNLS) for multiple imaging radiography (MIR) purposes. The algorithm employed for treating the MIR data collected at LNLS is described, and its reliability in extracting the distinct types of contrast that can be obtained with MIR is demonstrated by analyzing a test sample (thin polyamide wire). As a practical application, the possibility of studying ophthalmic tissues, corneal sequestra in this case, via MIR is investigated.

2008-01-11

320

Inertinite of fossil coal and molecular paleontology  

British Library Electronic Table of Contents (United Kingdom)

The etching method developed made it possible to observe under the microscope the finest components of the anatomical structure of coal-forming plants. The dependence of the effectiveness of etching of tissues on the concentrations of geopolymers (protocellulose and protolignin) in them was found. The study of tissues of this kind by the methods of local analysis (for example, X-ray microanalysis) allowed us to obtain the characteristics of the above geopolymers and to use them for the identification of the primary biochemical composition of fossil organic matter.

2011-01-01

321

Effect of KI on improving copper corrosion inhibition efficiency of benzotriazole in sulfuric acid electrolytes  

Energy Technology Data Exchange (ETDEWEB)

A synergistic effect exists when benzotriazole (BTAH) and iodide ions are used together to prevent the corrosion of copper in sulfuric acid. The nature of this effect has been studied systematically by using electrochemical techniques and X-ray photoelectron spectroscopy. The synergistic effect is due largely to the formation of a film of Cu(IBTA) complex and is probably polymeric in nature. This new complex film greatly depresses copper dissolution.

1993-10-01

322

Crystallization and preliminary X-ray diffraction studies of two thermostable ?-galactosidases from glycoside hydrolase family 36  

UK PubMed Central (United Kingdom)

α-Galactosidases from thermophilic organisms have gained interest owing to their applications in the sugar industry. The α-galactosidases AgaA, AgaB and AgaA A355E mutant from Geobacillus...Full Text Available

323

Collisional-radiative model for highly stripped ions  

Energy Technology Data Exchange (ETDEWEB)

Collisional-Radiative numerical models are commonly used to design or interpret experiments in atomic physics of laser-created plasmas, including X-ray laser studies. We describe our new code containing several options: average ion, more or less detailed configurations. It consists of an atomic data base coupled to subroutines evaluating ionic populations and emission and absorption coefficients. Numerical results are given to illustrate the capabilities of the code and to compare different models and types of approximation.

1986-10-01

324

Character of interaction of magnesium borates with water  

Energy Technology Data Exchange (ETDEWEB)

The nature of interaction of some boromagnesium minerals with water is studied, the main stages of interaction are established. The methods of thermo-gravimetric, X-ray phase and chemical analyses are applied to state intermediate and final phases of magnesium borate interaction with water. ''Preobrazhenskite'' - ''inderite'' paragenesis is established. The notion ''magnesium borate solubility'' is shown to be senseless.

1986-11-01

325

CT scan findings in cerebral paragonimiasis  

International Nuclear Information System (INIS)

Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies. (author).

1982-01-01

326

Study of the lattice parameter evolution of PWR irradiated MOX fuel by X-Ray diffraction; Etude de l'evolution du parametre cristallin des combustibles MOX irradies en rep par la methode de diffraction des rayons X  

Energy Technology Data Exchange (ETDEWEB)

Fuel irradiation leads to a swelling resulting from the formation of gaseous (Kr, Xe) or solid fission products which are found either in solution or as solid inclusions in the matrix. This phenomena has to be evaluated to be taken into account in fuel cladding Interaction. Fuel swelling was studied as a function of burn up by measuring the corresponding cell constant evolution by X-Ray diffraction. This study was realized on Mixed Oxide Fuels (MOX) irradiated in a Pressurized Water Reactor (PWR) at different burn-up for 3 initial Pu contents. Lattice parameter evolutions were followed as a function of burn-up for the irradiated fuel with and without an annealing thermal treatment. These experimental evolutions are compared to the theoretical evolutions calculated from the hard sphere model, using the fission product concentrations determined by the APPOLO computer code. Contribution of varying parameters influencing the ...

1995-07-01

327

X-ray stars in globular clusters  

Science.gov (United States)

The properties and kinetics of x-ray stars in globular clusters are described. Locations, configurations, star evolution, massive close binary systems, various mechanisms, and the x-ray burster properties are included. (JFP)

1977-10-01

328

X-ray dose enhancement effects  

International Nuclear Information System (INIS)

A brief description of the physical process of dose enhancement effects produced by X-ray radiation on materials is given, with emphasis on the influence on electronic devices. The damages caused by X-ray radiation dose enhancement is more serious than that of #gamma#-ray with higher energy.

329

Photoacoustic response to X-ray absorption in copper and brass  

Energy Technology Data Exchange (ETDEWEB)

The X-ray photoacoustic spectra of copper and brass (64.7 wt.% Cu and 35.3 wt.% Zn) have been measured at XANES (X-ray absorption near-edge structure) regions using synchrotron radiation. These spectra were compared with optical density of X-ray spectra. It is shown that the information derived from XANES is also included in the X-ray photoacoustic spectrum which reflects the heat production processes in copper and brass. However, the results showed that the increases and changes of the photoacoustic signal were different from those of the X-ray absorption coefficient at XANES regions. (author).

1990-09-01

330

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

Energy Technology Data Exchange (ETDEWEB)

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

1982-01-01

332

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

333

Ultrafast fluorescence dynamics of Sybr Green I/DNA complexes  

British Library Electronic Table of Contents (United Kingdom)

The ultrafast dynamics of the DNA fluorescent dye Sybr Green I (SG) has been studied in buffer, single-stranded (ssDNA), double-stranded (dsDNA) and triple-stranded DNA (tsDNA). The fluorescence quantum yield of SG increases dramatically when bound to DNA (including tsDNA). The fluorescence dynamics of the free SG has shown two decay components with 0.15-0.4ps and 1.3-2.1ps time constants, depending on the fluorescence wavelength. Upon binding to DNA, the dynamics becomes slower exhibiting four decay components. This is mainly due to the restriction of the internal motions of the dye caused by the relatively rigid environment of the dye complexed with DNA.

2010-01-01

334

Valence-electron configuration of Ti and Ni in Ti{sub x}Ni{sub 1-x} alloys from K{beta}-to-K{alpha} X-ray intensity ratio studies  

Energy Technology Data Exchange (ETDEWEB)

K{beta}-to-K{alpha} X-ray intensity ratios of Ti and Ni have been measured in pure metals and in alloys of Ti{sub x}Ni{sub 1-x} (x=0.7, 0.6, 0.5, 0.4 and 0.3) following excitation by 22.69 keV X-rays from a 10 mCi {sup 109}Cd radioactive point source. The valence-electron configurations of these metals were determined by corporation of measured K{beta}-to-K{alpha} X-ray intensity ratios with the results of multiconfiguration Dirac-Fock calculation for various valence-electron configurations. Valence-electron configurations of 3d-transition metals in alloys indicate significant differences with respect to the pure metals. Our analysis indicates that these differences arise from delocalization and/or charge transfer phenomena in alloys. Namely, the observed change of the valence-electron configurations of metals in alloys can be explained with the transfer of 3d electrons from one element to the other element and/or the ...

2010-06-15

335

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-10-11

336

Microstructural analysis of a plasmanitrided tool steel by means of metallography and X-ray diffraction; Mikrostrukturelle und roentgenographische Analysen an einem plasmanitrierten Schnellarbeitsstahl  

Energy Technology Data Exchange (ETDEWEB)

Nitriding leads to improved tribological and corrosive properties of iron alloy components. In order to study the effect of plasma nitriding parameters on the structure of compound layer and diffusion zone, a systematic variation of process parameters, temperature and process gas atmosphere has been carried out. Metallographic inspection, X-ray diffraction and glow discharge optical spectroscopy analysis (GDOES) were used in this investigation. The results clarified that depending on the amount of nitrogen in the gas atmosphere nitrided layers with and without compound layer can be generated in the surface of M2 tool steel for temperatures from 350 C to 500 C. For plasma nitriding in 5 vol.% Nitrogen and 95 vol.% Hydrogen no compact compound layer was formed. The gas mixture of 76 vol.% Nitrogen resulted in compound layer formation for all temperatures from 350 C to 500 C. X-ray phase analysis indicated an almost 100% ...

2001-09-01

337

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 ...

2009-05-27

338

Carbon beam irradiation of human monolayer cells  

Energy Technology Data Exchange (ETDEWEB)

The effect of the heavy particle irradiation on cell survival is different from that of X-ray irradiation. In Japan, heavy particles will be applied to cancer patients in the near future. This study was performed to determine the effect that carbon particle irradiation exerts to human monolayer cells in vitro, in comparison with the effect of 200 kVp X-ray. Two human cell lines, HeLaS3 and RMUG, were used. The irradiation was carried out by the RIKEN ring cyclotron and 200 kVp X-ray. The experimental procedure is explained. Also split dose experiment was carried out by applying equally divided doses at intervals of 2 - 4 hours. The Bragg curve of 135 MeV/n carbon beam through the lucite plates with different thickness is given. Thus the different LETs were obtained. The survival curves for 200 kVp X-ray and the various LETs of carbon beam are shown. The curves became steeper, and Do ...

1993-12-31

339

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 ...

2001-09-23

340

Fragmentation and ion-molecule reaction of diethylmercury radical cations: an ESR study in irradiated frozen freon matrices and spin trapping in liquid phase  

International Nuclear Information System (INIS)

The mono- and intramolecular cation-radicals (CR) reactions of diethylmercury in the CFCl_3, CFCl_2CF_2Cl matrices and CF_2BrCF_2Br and CFCl_3 freons vitrified mixture (1:1) were studied through the EPR method. Formation of radical products of transformations of the initial CR diethylmercury (X-ray radiation dose - 100-200 Gy at the temperature of 293 K) was studied through the spin trap of 2.4.6 - tri-tret-butylnitrosebenzene.

341

Phase-Sensitive Fluorescence Study of Mono-L-Aspartyl ...  

Science.gov (United States)

... of perylene were measured with the Shimadzu UV-2500 UV-VIS spectrophotometer (Kyoto, Japan) to determine their molar extinction coefficients. ...

2001-10-25

342

Biogenic iron oxyhydroxide formation at mid-ocean ridge hydrothermal vents: Juan de Fuca Ridge  

Energy Technology Data Exchange (ETDEWEB)

Here we examine Fe speciation within Fe-encrusted biofilms formed during 2-month seafloor incubations of sulfide mineral assemblages at the Main Endeavor Segment of the Juan de Fuca Ridge. The biofilms were distributed heterogeneously across the surface of the incubated sulfide and composed primarily of particles with a twisted stalk morphology resembling those produced by some aerobic Fe-oxidizing microorganisms. Our objectives were to determine the form of biofilm-associated Fe, and identify the sulfide minerals associated with microbial growth. We used micro-focused synchrotron-radiation X-ray fluorescence mapping (mu XRF), X-ray absorption spectroscopy (mu EXAFS), and X-ray diffraction (mu XRD) in conjunction with focused ion beam (FIB) sectioning, and highresolution transmission electron microscopy (HRTEM). The chemical and mineralogical composition of an Fe-encrusted biofilm was queried at ...

2008-05-22

345

Stabilization of synchrotron radiation x-ray beam by MOSTAB  

International Nuclear Information System (INIS)

Monochromator stabilization (MOSTAB) is a feedback control system to stabilize an x-ray beam of synchrotron radiation. It applies a feedback voltage to a piezo electric transducer attached to a double-crystal monochromator. We developed MOSTAB modules and examined their performances using SPring-8 beamlines. The x-ray beam position stabilization using MOSTAB was realized simultaneously with the x-ray beam intensity stabilization. As an example of its application, we performed EXAFS measurement with MOSTAB. (author)

2003-05-01

346

Spin evolution in wind-fed X-ray binaries  

International Nuclear Information System (INIS)

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

348

Possibilities of rayleigh-taylor instability measurement by X-ray phase imaging  

International Nuclear Information System (INIS)

X-ray imaging is a very useful plasma diagnostic method. A theoretical analysis of the x-ray phase imaging in the method based on Fresnel diffraction is given. The authors show it is a linear band pass filter, a property suit for Rayleigh-Taylor (R-T) instability measurement. The evaluation permits the possibility of R-T instability measurement in x-ray phase imaging

350

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

International Nuclear Information System (INIS)

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

2001-09-23

351

Ectopic Ureter  

Science.gov (United States)

... such as renal flow scan or a formal kidney X-ray, called an intravenous pyelogram ( IVP ), may help ...

353

Nanocrystallization of the amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloys studied by the Moessbauer spectroscopy  

International Nuclear Information System (INIS)

Formation of the soft magnetic nanostructure in amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloy due to heat treatment is studied by the Moessbauer, differential scanning calorimetry, and X-ray diffraction techniques. Annealing at temperatures 520-580 "oC leads to the formation of extremely soft nanocrystalline alloy as revealed by the rf-Moessbauer measurements. The superparamagnetic behaviour was observed for the alloy annealed at 620-640 "oC. At higher annealing temperatures good soft magnetic properties deteriorate. (author)

2001-09-23

354

Moessbauer study of magnetic anisotropy in amorphous Fe_4_0Ni_3_8Mo_4B_1_8 (METGLAS 2628MB)  

International Nuclear Information System (INIS)

The room-temperature anisotropy of amorphous Fe_4_0Ni_3_8Mo_4B_1_8 (METGLAS 2628MB) ribbons after various heat treatments has been studied by Moessbauer spectroscopy. The average magnetization direction becomes significantly more out-of-plane after heating above 650 K but below the crystallization temperature. X-ray diffractograms suggest an atomic rearrangement has occurred. (orig.).

355

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

356

Coherent Synchrotron Radiation as a Diagnostic Tool for the LCLS Longitudinal Feedback System  

Energy Technology Data Exchange (ETDEWEB)

The Linac Coherent Light Source (LCLS) will be the world's first x-ray free-electron laser (FEL). To ensure the vitality of FEL lasing, a longitudinal feedback system is required together with other diagnostics. In this paper, we study the possibility of using Coherent Synchrotron Radiation (CSR) from the chicane as a diagnostic tool for bunch length feedback. Studies show that CSR is a good candidate, even for a non-Gaussian, double-horn longitudinal charge distribution as in the LCLS. We further check the possibility for detecting possible microbunching.

2005-06-15

357

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

358

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

359

Palladium(II) and platinum(II) saccharinate complexes containing pyridine and 3-acetylpyridine: Synthesis, crystal structures, fluorescence and thermal properties  

British Library Electronic Table of Contents (United Kingdom)

New palladium(II) and platinum(II) complexes of saccharinate (sac), trans-[Pd(py)"2(sac)"2] (1), cis-[Pt(py)"2(sac)"2] (2), trans-[Pd(3-acpy)"2(sac)"2] (3) and cis-[Pt(3-acpy)"2(sac)"2] (4) (py=pyridine and 3-acpy=3-acetylpyridine) have been synthesized. Elemental analysis, UV-Vis, IR, NMR and TG/DTA characterizations have been carried out. The structures of 1-4 were determined by X-ray diffraction. The palladium(II) and platinum(II) ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of py or 3-acpy, forming a distorted square-planar geometry. The palladium(II) complexes (1 and 3) are trans isomers, while the platinum(II) complexes (2 and 4) are cis isomers. The mononuclear species in the solid state are connected by weak intermolecular C-H...O hydrogen bonds, C-H...@...

2011-01-01

360

Measuring instrument for radiometric monitoring of solids and heavy metals in water  

International Nuclear Information System (INIS)

A combination of measuring instruments, consisting of a Beta-Sedimeter and a radionuclide X-ray fluorescence instrument, is described. With the Beta-Sedimeter the C-14-radiation is measured. Through direct irradiation with photons of a Pu238-source in an ancillary irradiation chamber and energy dispersing measurement of the K- and L-radiation resp. of the excited heavy metals with the aid of a Si(Li)-semiconductor detector and a 4-channel analyzer the heavy metal concentrations of the heavy metals Zn, Cr, Ni and Pb are determined. For the determination of cadmium the indirect excitation with Am-241 and Dy-targets is described. The system produces records and operates fully automatically in a step-by-step mode with a testing cycle of 45 minutes. In connection with the process monitoring of the wastewater from a zinc plating plant during a period of 8 months the concentration of the solid material and of the metals Cr and Zn, which were ...

1979-01-01

361

High sensitivity detection and characterization of the chemical state of trace element contamination on silicon wafers  

CERN Document Server

Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO sub 2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to levels that must be improved before new processes can be put into production. It should be noted that much of this metal contamination occurs during the wet chemical etching and rinsing steps required for the manufacture of integrated circuits and industry is actively developing new processes that have already brought the metal contamination to levels beyond the measurement capabilities of conventional analytical techniques. The measurement of these extremely low contamination levels has required the use of synchrotron radiation total reflection X-ray ...

2003-01-01

362

Development of highly reliable screening by using x-ray fluorescence spectrometry. Applications to determine lead in tin plated and tin-bismuth plated samples  

International Nuclear Information System (INIS)

A highly reliable screening method was developed for the determination of lead in tin plated layers and tin-bismuth plated layers. The contents of lead in the layers of the various samples were determined by inductively coupled plasma optical emission spectrometry. The calibration curve for lead in the tin and tin-bismuth plated layers by using WD-XRF exhibited linear correlation from 130 #mu#g/g to 2070 #mu#g/g. Calibration curve of lead normalized with Pb-L#alpha#/Sn-K#alpha# intensity was more linear, and this method was possible to evaluate very small sample. The calibration curve for lead in the tin plated layers by using ED-XRF was good linearly, but it for lead in the tin-bismuth plated layers was affected by Pb-L#alpha# spectrum and Bi-L#alpha# spectrum overlap each other. It was effective for decreasing affect of Bi-L#alpha# spectrum by using curve fitting method. (author)

2009-03-01

363

An Investigation of the Relationship Between Tritium in Groundwater and the Dendrochronology of Tritium in Trees at the Savannah River Site. Final report  

Energy Technology Data Exchange (ETDEWEB)

This project was supported through ERDA to demonstrate that the temporal distribution of tritium can be documented by the analysis of bound hydrogen in annual tree-ring samples. The project focuses on two sample locations at the Savannah River Site (SRS), a nuclear material production facility located in Aiken, SC. The SRS provided samples of cross-sections from a single tree that were to be pooled together for analysis. Annual tree-rings were identified in each cross-section sample and separated for the period 1954 to 1993. These annual samples were ground and chemically treated to separate the hollocellulose fraction of the wood, then subsequently combusted and the resulting water counting using low-level liquid scintillation counting equipment. Additionally, the ground annual tree-rings were gamma-counted to determine any temporal variation in radionuclide activity and analyzed with x-ray fluorescence to find any temporal variation in ...

1995-03-21

364

Evidence of FCC titanium hydride formation in #beta# titanium alloy: An X-ray diffraction study  

International Nuclear Information System (INIS)

Three types of titanium hydrides have been reported: #delta#, #epsilon# and #gamma# hydrides. The #delta# hydride forms in the composition range from TiH/sub 1.5/ to TiH/sub 1.99/ and has a CaF/sub 2/ structure with metal atoms on an fcc lattice and hydrogen atoms randomly occupying tetrahedral interstitial sites. At higher hydrogen concentrations, TiH/sub 2/, the fct (c/a # #epsilon# transformation is apparently diffusionless, similar to that operating in the cubic/tetragonal transformation in zirconium hydride. The metastable fct #gamma# hydride having a c/a value of 1.09 or 1.12 forms from solid solutions of hydrogen in the hcp #alpha# matrix. While the titanium hydride precipitation in #alpha#-Ti and its alloys has attracted extensive investigation, hydride formation in bcc #beta#-Ti alloys has rarely been studied because they have not been thought to be liable to hydride formation. This paper shows conclusive evidence for the fcc #delta# hydride phase ...

365

Are Optically-Selected Quasars Universally X-Ray Luminous? X-Ray/UV Relations in Sloan Digital Sky Survey Quasars  

CERN Document Server

We analyze archived Chandra and XMM-Newton X-ray observations of 536 Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) quasars (QSOs) at 1.7 <= z <= 2.7 in order to characterize the relative UV and X-ray spectral properties of QSOs that do not have broad UV absorption lines (BALs). We constrain the fraction of X-ray weak, non-BAL QSOs and find that such objects are rare; for example, sources underluminous by a factor of 10 comprise $\\la$2% of optically-selected SDSS QSOs. X-ray luminosities vary with respect to UV emission by a factor of $\\la$2 over several years for most sources. UV continuum reddening and the presence of narrow-line absorbing systems are not strongly associated with X-ray weakness in our sample. X-ray brightness is significantly correlated with UV emission line properties, so that relatively X-ray weak, non-BAL ...

2008-01-01

366

Future of X-ray phase imaging in medical imaging technology  

International Nuclear Information System (INIS)

Weakly absorbing materials, such as biological, soft tissues, can be imaged by generating contrast due to the phase shift of X-rays. In the past decade, several methods for X-ray phase imaging were proposed and demonstrated. The performance of X-ray phase imaging is attractive in the field of medical imaging technology, and its development for practical use is expected. Many methods, however, have been developed under the assumption of the use of synchrotron radiation, which is an obstacle to practical use. The method based on Talbot (-Lau) interferometry enables us to use a compact X-ray source, and its development is expected as a breakthrough for medical applications. (author)

2007-04-01

367

Variability and spectral modeling of the hard X-ray emission of GX 339-4 in a bright low/hard state  

CERN Document Server

We study the high-energy emission of the Galactic black hole candidate GX 339-4 using INTEGRAL/SPI and simultaneous RXTE/PCA data. By the end of January 2007, when it reached its peak luminosity in hard X-rays, the source was in a bright hard state. The SPI data from this period show a good signal to noise ratio, allowing a detailed study of the spectral energy distribution up to several hundred keV. As a main result, we report on the detection of a variable hard spectral feature (>150 keV) which represents a significant excess with respect to the cutoff power law shape of the spectrum. The SPI data suggest that the intensity of this feature is positively correlated with the 25 - 50 keV luminosity of the source and the associated variability time scale is shorter than 7 hours. The simultaneous PCA data, however, show no significant change in the spectral shape, indicating that the source is not undergoing a canonical ...

2010-01-01

368

Use of the parmbsc0 force field and trajectory analysis to study the binding of netropsin to the DNA fragment (5'CCAATTGG)2 in the presence of excess NaCl salt in aqueous solution  

British Library Electronic Table of Contents (United Kingdom)

The parmbsc0 force field was applied to study in detail the binding of netropsin, at a salt concentration of 0.28M Na^+, to the minor groove of an 8-mer (5'CCAATTGG)2 DNA duplex forming a netropsin.DNA complex which previously has been characterized by X-ray crystallography, albeit with the use of closely related DNA duplexes. The X-ray structure revealed that the terminal guanidinium and amidinium groups of netropsin interact with the extreme ends of the palindromic AATT sequence of the receptor DNA. The parmbsc0 parameters of B-DNA and AMBER v9 parameters of netropsin generated a stable 6ns molecular dynamics (MD) trajectory for a 1:1 class I binding motif of this complex. Trajectory analysis for the salt and hydration effects on the binding of netropsin to the 8-mer DNA duplex revealed ...

2011-01-01

369

Study of the crystallographic architecture of corals at the nanoscale by scanning transmission X-ray microscopy and transmission electron microscopy.  

Science.gov (United States)

We have investigated the nanotexture and crystallographic orientation of aragonite in a coral skeleton using synchrotron-based scanning transmission X-ray microscopy (STXM) and transmission electron microscopy (TEM). Polarization-dependent STXM imaging at 40-nm spatial resolution was used to obtain an orientation map of the c-axis of aragonite on a focused ion beam milled ultrathin section of a Porites coral. This imaging showed that one of the basic units of coral skeletons, referred to as the center of calcification (COC), consists of a cluster of 100-nm aragonite globules crystallographically aligned over several micrometers with a fan-like distribution and with the properties of single crystals at the mesoscale. The remainder of the skeleton consists of aragonite single-crystal fibers in crystallographic continuity with the nanoglobules comprising the COC. Our observation provides information on the nm-scale processes that led to biomineral formation in this ...

2011-05-05

370

Size-dependent surface plasmon resonance in silver silica nanocomposites  

Energy Technology Data Exchange (ETDEWEB)

Silver silica nanocomposites were obtained by the sol-gel technique using tetraethyl orthosilicate (TEOS) and silver nitrate (AgNO{sub 3}) as precursors. The silver nitrate concentration was varied for obtaining composites with different nanoparticle sizes. The structural and microstructural properties were determined by x-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopic (XPS) studies were done for determining the chemical states of silver in the silica matrix. For the lowest AgNO{sub 3} concentration, monodispersed and spherical Ag crystallites, with an average diameter of 5 nm, were obtained. Grain growth and an increase in size distribution was observed for higher concentrations. The occurrence of surface plasmon resonance (SPR) bands and their evolution in the size range 5-10 nm is studied. For ...

2008-02-20

371

Radiation, adriamycin, and skin reactions: effects of radiation and drug fractionation, hyperthermia, and tetracycline. [X rays  

Energy Technology Data Exchange (ETDEWEB)

The effect of adriamycin in combination with radiation on the skin reactions of mouse feet has been examined under a variety of experimental conditions including: (a) hyperthermic treatment of the foot immediately following adriamycin administration, with the former given either just before or just after x irradiation, and (b) fractionated treatments of drug and radiation in a variety of sequences over an 18-day period. In the case of the most severe hyperthermic treatment, no increased radiation reactions were observed in the presence of adriamycin. However, in the case of the less severe hyperthermic treatment a small but significant increase in skin reactions was observed. In the study of fractionated drug and radiation treatments, an enhancement of reaction in those animals receiving combined modality treatment over those receiving radiation alone was seen in those groups where the initiation of drug treatment succeeded the initiation of radiation treatment by ...

1981-06-01

372

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 ...

2011-03-31

373

Phantom and animal imaging studies using PLS synchrotron X-rays  

CERN Document Server

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

2001-01-01

374

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

Science.gov (United States)

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

2009-12-01

375

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

International Nuclear Information System (INIS)

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

2009-12-01

376

Element-selective thermal x-ray magnetic circular dichroism study through the magnetic compensation temperature of Ho{sub 6}Fe{sub 23}  

Science.gov (United States)

We present an x-ray magnetic circular dichroism (XMCD) study performed on both Ho{sub 6}Fe{sub 23} and Y{sub 6}Fe{sub 23} compounds as a function of the temperature. The combined analysis of both Fe K-edge and Ho L{sub 2,3}-edge XMCD spectra recorded through the magnetic compensation transition allows us to disentangle the thermal dependence of both Fe and Ho magnetic moments in Ho{sub 6}Fe{sub 23}. In addition, contributions from Ho ions to the Fe K-edge XMCD signals and, conversely, from Fe ions to the Ho L{sub 2,3}-edge XMCD spectra have been clearly identified. These extra contributions, arising from the strong Fe(3d)-Ho(5d) hybridization, have been isolated from the spectra and correlated with the magnetic state of both Ho and Fe ions surrounding the absorbing site. The influence of these contributions to the values of the orbital and spin moments derived by using sum rule analysis is also shown.

2005-09-01

377

Crystalline O,O'-di-sec-butyl and O,O'-diethyl dithiophosphate platinum(II) complexes: Synthesis, 13C and 31P CP/MAS NMR, single crystal X-ray diffraction studies and thermal behaviour  

British Library Electronic Table of Contents (United Kingdom)

Crystalline bis(O,O'-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S'-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from...

2011-01-01

378

Crystal growth, structural and optical characterization of a semi-organic single crystal for frequency conversion applications  

International Nuclear Information System (INIS)

Single crystals of semi-organic L-histidine hydrobromide have been grown by slow evaporation technique from a mixture of L-histidine and hydrobromic acid in aqueous solution at ambient temperature. From high-resolution X-ray diffraction analysis, the crystalline perfection of the grown crystal has been studied. Single crystal X-ray diffraction analyses, Nuclear Magnetic Resonance spectral analysis, Thermo-Gravimetry (TG), Differential Thermal Analysis (DTA) and hardness test have been employed to characterize the as-grown crystals. The UV cutoff wavelength of the grown crystal is below 300 nm and has a wide transparency window, which is suitable for second harmonic generation of laser in the blue region. Nonlinear optical characteristics have been studied using Q switched Nd:YAG laser (#lambda#=1064 nm). The second harmonic generation conversion efficiency of the grown crystals confirms their ...

2010-12-15

379

Change in pore structure of coals by activation with KOH; KOH fukatsushita sekitan no saiko kozo  

Energy Technology Data Exchange (ETDEWEB)

Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was studied. The results are summarized as follows: (1) The yield and absorption ability of ...

1996-10-28

380

Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens  

Energy Technology Data Exchange (ETDEWEB)

Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 ...

2008-04-02

381

Three-dimensional image display of brain tumor utilizing a modified voxel method  

Energy Technology Data Exchange (ETDEWEB)

The patch and voxel methods are representative examples of the ways in which multi-slice images may be displayed three-dimensionally by means of computer-graphics. Each of them have advantages and disadvantages and they are mutually complementary. We have developed algorithms for a modified voxel method which incorporates the advantages of the patch methods. We have applied this to the three-dimensional image display of brain tumor with excellent results. The three-dimensional reconstructions used for clinical application in this study were derived from X-ray CT images.

1988-08-01

382

Synthesis of CdSe nanoparticles and their effect on the antioxidant activity of Spirulina platensis and Porphyridium cruentum cells  

International Nuclear Information System (INIS)

Single-crystalline cadmium selenide nanoparticles were obtained using high-temperature solution phase synthesis (HTSPS) synthesis. X-Ray powder diffraction and transmission electron microscopy were used to confirm the crystallinity and morphology of the resulting nanoparticles. To study the action of CdSe on antioxidant activity, we selected two biotechnological important strains of microalgae: cyanobacteria Spirulina platensis and red microalgae Porphyridium cruentum. In the case of Porphyridium cruentum, the obtained results demonstrated an increase in the productivity. For Spirulina platensis, the presence of the compound in the cultivating medium decreased the productivity of cyanobacteria.

2011-07-07

383

Surface modification of 17-4PH stainless steel by DC plasma nitriding and titanium nitride film duplex treatment  

Energy Technology Data Exchange (ETDEWEB)

17-4PH stainless steel was modified by direct current (DC) plasma nitriding and titanium nitride film duplex treatment in this study. The microstructure, wear resistance and corrosion resistance were characterized by X-ray diffraction (XRD), pin-on-disk tribological test and polarization experiment. The results revealed that the DC plasma nitriding pretreatment was in favor of improving properties of titanium nitride film. The corrosion resistance and wear resistance of duplex treatment specimen was more superior to that of only coated titanium nitride film.

2007-04-15

384

Surface modification of 17-4PH stainless steel by DC plasma nitriding and titanium nitride film duplex treatment  

International Nuclear Information System (INIS)

17-4PH stainless steel was modified by direct current (DC) plasma nitriding and titanium nitride film duplex treatment in this study. The microstructure, wear resistance and corrosion resistance were characterized by X-ray diffraction (XRD), pin-on-disk tribological test and polarization experiment. The results revealed that the DC plasma nitriding pretreatment was in favor of improving properties of titanium nitride film. The corrosion resistance and wear resistance of duplex treatment specimen was more superior to that of only coated titanium nitride film.

2007-04-01

385

Study of titanium-niobium alloys manufactured by magnesium thermic reduction of chlorides  

International Nuclear Information System (INIS)

Chemical and phase homogeneity of titanium-niobium sponge, produced by a combined magnesium-thermic reduction of niobium pentachloride and titanium tetrachloride mixtures, is investigated. It is ascertained that a sponge consists of spherical shape particles and has a large number of pores. Particle sizes are reduced with niobium being substituted for titanium from 50-500 #mu#m for titanium sponge to 1-40 #mu#m for niobium one, which testifies to the bormation in a titanium-niobium sponge of an alloy and not a mechanical mixture. A number of solid solutions is detected by X-ray phase analysis. Lattice parameters are determined.

386

Study of penetration depth for V"+ with low energy implanted in peanut seeds  

International Nuclear Information System (INIS)

The penetration depth and concentration distribution for vanadium ions with low energy implanted into the dry peanut seeds is determined by scanning electron microscope and X-ray energy dispersion spectrometer. The results show that the depth-concentration distribution is a Gaussian distribution with a long tail and the maximum penetration depth is about 13.6 #mu#m for V"+ with 200 keV in cotyledon of the peanut. The experimental result of the implanted V"+ range in the peanut seeds is compared with the calculating value of the TRIM95

2002-11-01

387

Structure and electrical resistance of dispersion-strengthened vacuum-deposited Cu?Al2O3 nanocomposites  

British Library Electronic Table of Contents (United Kingdom)

Methods of X-ray diffraction and transmission electron microscopy were used to study the microstructure of dispersion-strengthened Cu-Al2O3 nanocomposites obtained by the method of simultaneous deposition of Cu and Al2O3 from the vapor phase. The effect of the size of particles of the oxide (Al2O3) and of their content on the electrical resistance of the composite has been considered. The results obtained make it possible to suppose that the main structural factor that determines the electrical resistance of the composite are nanodispersed particles of Al2O3 with a size of less than 20 nm.

2011-01-01

388

Structural transformations of metastable #alpha#''-phase during cold deformation  

International Nuclear Information System (INIS)

Phase transformations occuring during cold deformation in hardened #alpha#+#beta# titanium alloy of the Ti-Al-Mo-Zr-Sn-Si system with 10% summary content of alloying elements are studied by X-ray diffraction analysis. Two stages of trapsformation of metastable #alpha#''-phase are found. A conclusiop is made that ability of the alloy containing #alpha#''-phase to cold deformation is determined by the presence of favourable texture, by high degree of metastability and by volume portion of #alpha#''-phase in the alloy structure.

389

Structural and magnetic studies on the enhancement of the giant magnetoimpedance by ion irradiation  

British Library Electronic Table of Contents (United Kingdom)

The mechanism of abrupt increase of the giant magneto impedance (GMI) ratio in the ion irradiated Co-based amorphous ribbon has been investigated. The grazing incident X-ray diffraction and transmission electron microscope were used to characterize the samples before and after ion irradiation. The GMI-ratio considerably increased in the ion irradiated samples and the GMI response showed strong dependence on the driving frequencies. The Barkhausen noise (BN) signals are increased for the Ar ion irradiated sample with dose of 1x10^1^7 ion/cm^2. The results are interpreted in terms of GMI variation associated with domain wall dynamics.

2011-01-01

390

Similarity between the primary and secondary air-assisted liquid jet breakup mechanism  

CERN Document Server

we report an ultrafast synchrotron x-ray phase contrast imaging study of the primary breakup mechanism of a coaxial air-assisted water jet. We demonstrate that there exist great similarities in the phenomenology of primary breakup with that of the secondary breakup. Especially, a membrane-mediated breakup mechanism dominates the breakup process for a wide range of air speeds. This finding reveals the intrinsic connections of these two breakup regimes and has deep implications on the unified theoretical approach in treating the breakup mechanism of high speed liquid jet.

2007-01-01

391

Silicidation in Pd/Si thin film junction-Defect evolution and silicon surface segregation  

Energy Technology Data Exchange (ETDEWEB)

Depth resolved positron annihilation studies on Pd/Si thin film system have been carried out to investigate silicide phase formation and vacancy defect production induced by thermal annealing. The evolution of defect sensitive S-parameter clearly indicates the presence of divacancy defects across the interface, due to enhanced Si diffusion beyond 870 K consequent to silicide formation. Corroborative glancing incidence X-ray diffraction (GIXRD), Auger electron spectroscopy (AES) and Rutherford backscattering spectrometry (RBS) have elucidated the aspects related to silicide phase formation and Si surface segregation.

2007-09-25

392

Significance of major, minor and trace elements analysis of rocks by WDXRFS in litho geochemistry vis a vis uranium exploration in parts of India  

International Nuclear Information System (INIS)

This paper discusses essentially the role of WDXRFS based multi element data in uranium exploration, with special reference to India. The state of art MagiX-PRO WDXRFS with 4 kW end window x-ray tubes has been used in the present study as an indispensable geo-analytical tool for the analysis of major and selected trace elements at ppm to percentage level, with high precision and relatively better accuracy

2010-10-01

393

Scintigraphic detection of a radiologically equivocal fracture  

Energy Technology Data Exchange (ETDEWEB)

This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period.

1988-04-01

394

Scintigraphic detection of a radiologically equivocal fracture  

International Nuclear Information System (INIS)

This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period. (orig.).

395

Production of a potassium silicate fertilizer from fly ash and red mud  

Energy Technology Data Exchange (ETDEWEB)

A study is reported of the use of three types of fly ash as a raw material in the production of a potassium silicate fertilizer. The results of high-temperature X-ray diffraction, calcination tests and chemical analyses indicate that a potassium silicate fertilizer conforming with fertilizer specifications can be produced by appropriate regulation of calcining temperature and the amounts of Fe/sub 2/0/sub 3/, Al/sub 2/O/sub 3/, MgO and CaO added. The results of tests of fertilizers incorporating red mud are also reported.

1985-01-01

396

PET/CT cardiology: an area whose boundaries are still out of sight  

International Nuclear Information System (INIS)

Positron emission tomography (PET) and X-ray computed tomography (CT) performed with PET/CT cameras allow us to obtain concurrently information on the presence and degree of alterations of myocardial perfusion and metabolism and on coronary arteries calcification. Furthermore, by gated myocardial perfusion studies, PET may provide crucial information on regional coronary blood flow reserve and endothelial dysfunction. A number of recent papers provide some insight on the potential of PET/CT in cardiology and in the assessment of various cardiovascular diseases including various types of vasculitis and metabolic diseases.

2006-05-01

397

Organ doses to atomic bomb survivors during photofluorography, fluoroscopy and computer tomography  

Energy Technology Data Exchange (ETDEWEB)

Doses to the salivary glands, thyroid gland, breast, lung, stomach and colon during mass radiological gastric screening, mass radiographic chest screening, upper gastrointestinal series and computed tomography were determined by exposing a female human phantom to simulated radiological X-ray examinations as performed in community hospitals. The doses were measured using thermoluminescent dosemeters, and the results will be used to document organ doses received by participants in the Atomic Bomb Casualty Commission/Radiation Effects Research Foundation Adult Health Study. (Author).

1991-08-01

398

Organ doses to atomic bomb survivors during photofluorography, fluoroscopy and computer tomography  

International Nuclear Information System (INIS)

Doses to the salivary glands, thyroid gland, breast, lung, stomach and colon during mass radiological gastric screening, mass radiographic chest screening, upper gastrointestinal series and computed tomography were determined by exposing a female human phantom to simulated radiological X-ray examinations as performed in community hospitals. The doses were measured using thermoluminescent dosemeters, and the results will be used to document organ doses received by participants in the Atomic Bomb Casualty Commission/Radiation Effects Research Foundation Adult Health Study. (Author).

1991-01-01

399

Mineral analysis in experimental corneal scars. An EDAX study  

Energy Technology Data Exchange (ETDEWEB)

Central penetrating excisional wounds were made in the corneas of 12 rabbits and 10 trout. The scar tissue and the surrounding cornea were compared using a new method for assessing inorganic elements in the cornea: the scanning electron microscopy and energy dispersive analysis of x-ray (EDAX). Semiquantitative determination of inorganic elements within the range of atomic numbers 9-93 in the periodic system was performed, comparing the relative concentration of those elements in the scar tissue to the surrounding cornea. Results showed that calcium was the only element higher in the healing wound than in the surrounding cornea.

1988-01-01

400

Measurement of stress in materials using chromium K/sub. beta. / radiation  

Energy Technology Data Exchange (ETDEWEB)

Bragg peaks obtained in X-ray stress analysis studies are often asymmetric. The use of K/sub ..beta../ rather than K/sub ..cap alpha../ radiation simplifies the problem of peak location, as only one Bragg peak needs to be analysed. It is shown, however, that the common practice of fitting a parabola to the top 15% of the data in a Bragg peak in order to determine the peak position, when the fitted region is asymmetric, can lead to large errors in the calculated stress. Asymmetric pseudo-Lorentzian functions have been found to provide the most satisfactory fits.

1983-01-01

401

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

402

EXAFS Study of Semimetal-Semiconductor Transition of Bismuth Clusters  

International Nuclear Information System (INIS)

Extended X-ray absorption fine structure (EXAFS) measurements of bismuth clusters in the temperature range of 23 -300 K have been performed using synchrotron radiation in order to investigate the size dependent phase transition. The inter-atomic distances around 3.0 A and 3.6 A are attributed to the nearest neighbors within the layer and between layers, respectively. EXAFS functions were analysed by the curve fitting method within a symmetric distribution approximation. The nearest neighbor distance of the 0.5 nm thick films is shorter than that of the 300 nm thick films at all the temperatures, which is related to the reduction of the inter-layer correlation.

2007-02-02

403

Diagnosis of peanut inhalation by MRI  

International Nuclear Information System (INIS)

We describe a 16-month-old boy presenting with stridor and fever. The chest X-ray suggested inhalation of a foreign body but here was no history of this. A high spot a T_1-weighted chest MRI was due to a peanut which was seen to have moved from the right main bronchus to the left inferior bronchus, between the two MRI studies. MRI can provide information on position and size of the peanut, the conditons of the surrounding tissues and may be also useful in treatment. We consider MRI to be a valuable new method for the diagnosis of peanut inhalation. (orig./GDG).

1992-01-01

404

Crystal structure of telluric acid ammonium phosphate (TAAP) in the paraelectric phase  

Energy Technology Data Exchange (ETDEWEB)

Crystal structure of monoclinic telluric acid ammonium phosphate (TAAP) has been studied by an X-ray diffraction method in the paraelectric phase at 333 K and in the ferroelectric phase at room temperature. It is confirmed that the space group in the paraelectric phase is P2/n. Comparison of the results between the two temperatures suggests that the plane which is made by the PO{sub 4} tetrahedron linked by hydrogen bonds has an important role for the ferroelectric phase transition. This plane is almost parallel to the direction of spontaneous polarization.

2005-01-15

405

Comparative study of passive films of different stainless steels developed on alkaline medium  

International Nuclear Information System (INIS)

Evolution of the passive films formed on AISI 304L and duplex stainless steel SAF 2205 in NaOH 0.1 M was investigated using cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). Special attention is paid to the effect of Mo in the generation of the films. Results point out to the stabilising effect of the molybdates on the surface of the film, enhancing the formation of a thin layer on the SAF 2205 with a higher Cr/Fe ratio.

2004-07-30

406

Changes in the structure and superconducting transition temperature of A-15 compounds under the effect of high pressure and shear strain  

Energy Technology Data Exchange (ETDEWEB)

The study is concerned with the combined effect of high pressure and shear strain on the properties of the A-15 intermetallics Nb3Sn and Nb3Al0.75Ge0.25. The properties discussed are the superconducting transition temperature, the width and intensity of the X-ray diffraction lines, and the width and shape of the Mossbauer absorption lines. It is shown that the combined effect of high pressure and shear strain leads to an intense generation of defects in polycrystalline specimens; the size of the ordered regions does not exceed 300 A even under the least severe conditions. 5 references.

1985-01-01

407

Annealing, lattice disorder and non-Fermi liquid behavior in UCu4Pd  

Energy Technology Data Exchange (ETDEWEB)

The magnetic and electronic properties of non-Fermi liquid UCu{sub 4Pd} depend on annealing conditions. Local structural changes due to this annealing are reported from UL{sub III}- and Pd K-edge x-ray absorption fine-structure measurements. In particular, annealing decreases the fraction of Pd atoms on nominally Cu 16e sites and the U-Cu pair-distance distribution width. This study provides quantitative information on the amount of disorder in UCu{sub 4Pd} and allows an assessment of its possible importance to the observed non-Fermi liquid behavior.

2002-07-30

408

Analysis of Longitudinal Space Charge Effects With Radial Dependence  

Energy Technology Data Exchange (ETDEWEB)

Longitudinal space charge (LSC) force can be a main effect driving the microbunching instability in the linac for an x-ray free-electron laser (FEL). In this paper, the LSC-induced beam modulation is studied using an integral equation approach that takes into account the transverse (radial) variation of LSC field for both the coasting beam limit and bunched beam. Changes of beam energy and the transverse beam size can be also incorporated. We discuss the validity of this approach and compare it with other analyses as well as numerical simulations.

2005-09-30

409

An influence of ion bombardment on plasma nitriding process of Ti6Al14V alloy at 843 K temperature  

International Nuclear Information System (INIS)

This work presents results of investigations on d.c. glow discharge nitriding of #alpha#+#beta# Ti-6Al-4V titanium alloy. The treatment was performed at 843 K in nitrogen-hydrogen atmosphere, pressure 300 Pa. Special attention was paid to nitriding mechanism and determination of the role of ion bombarding in nitriding process of titanium alloys. Produced as a result of d.c. plasma nitriding surface layers were subjected to macroscopic observations, microstructure studies, microhardness testing and X-ray analysis. (author)

2004-06-20

410

Detection of constitutive heterodimerization of the integrin Mac-1 subunits by fluorescence resonance energy transfer in living cells  

International Nuclear Information System (INIS)

Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to #beta#_2 subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasma membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan ...

2006-08-04

411

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

Energy Technology Data Exchange (ETDEWEB)

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

2001-05-16

412

Elastic properties and structural studies on some zinc-borate glasses derived from ultrasonic, FT-IR and X-ray techniques  

Energy Technology Data Exchange (ETDEWEB)

Glasses in the system (1 - x) [29Na{sub 2}O- 4Al{sub 2}O{sub 3}- 67B{sub 2}O{sub 3}]- xZnO (0 {<=} x {<=} 35 mol%), have been prepared by the melt quenching technique. Elastic properties, X-ray and FT-IR spectroscopic studies have been employed to study the role of ZnO on the structure of the investigated glass system. Elastic properties and Debye temperature have been investigated using sound wave velocity measurements at 4 MHz at room temperature. The results showed that the density increases and the molar volume decreases while both sound velocities and the determined glass transition temperatures decrease with increase in x. X-ray and infrared spectra of the glasses reveal that the borate network consists of diborate units and is affected by the increase in the concentration of ZnO content. These results are interpreted in terms of the decrease in the N{sub 4} values (fraction of ...

2009-05-05

413

X-ray study of CuGa_xIn_1_-_xSe_2 solid solutions  

International Nuclear Information System (INIS)

The semiconducting compound CuGa_xIn_1_-_xSe_2 crystallizes in the chalcopyrite structure (space group Ianti 42d, Z=4). The X-ray powder data for x=1, 0.75, 0.6, 0.5, 0.4, 0.25 and 0.0 have been collected and it is found that the lattice parameters a and c and their ratio c/a vary linearly with x. Thus the composition of any chalcopyrite in the pseudo-binary system CuGaSe_2 and CuInSe_2 can be obtained from the accurate lattice parameters. The crystallite size determined from the (112) plane is minimum for x=0.50 (#propor to#1000 A) and away from x=0.50 it increases. A value of u=0.240 (5) has been established for fixing, the Se-atom positions in the CuGa_0_._5In_0_._5Se_2 solid solution. The JCPDS Diffraction File No. for CuInSe_2 is 40-1487 and for CuGa_0_._5In_0_._5Se_2 is 40-1488. (orig.).

1989-12-01

414

Time-Resolved Aerosol Collector for CCSEM/EDX Single Particle Analysis  

Energy Technology Data Exchange (ETDEWEB)

An automated Time Resolved Aerosol Collector (TRAC) has been developed for sequential sampling of field-collected aerosols for laboratory-based Computer Controlled Scanning Electron Microscopy/Energy Dispersed X-ray (CCSEM/EDX) single particle analysis. The collector is optimized for use of grid-supported 20 nm carbon films as deposition substrates. The carbon films have low enough X-ray background to permit EDX analysis down to 0.1-0.2 ?m particles, including detection of low-Z elements: C, N, & O. The TRAC provides unattended sampling onto a set of 151 individual grids, at sequential time intervals as short as 1 min. After collection, the samples are sealed and refrigerated pending analysis. The utility of the TRAC-CCSEM/EDX approach is exemplified using the aerosol samples collected during the Texas 2000 Air Quality Studies (Aug. 15 ? Sept. 15, 2000). We are able to quantitatively follow the time evolution in the ...

2003-01-02

415

Stoichiometry controlled conversion efficiency in nanostructured heterojunction solar cell of CdS/CuInSXSe2-X grown by chemical ion exchange method at room temperature  

British Library Electronic Table of Contents (United Kingdom)

Here in the present paper, we report on growth of stoichiometric and nonstoichiometric nanostructured heterojunction solar cell of CdS/CuInSXSe2-X varying X from 0 to 2 in the interval of 0.5 using cost effective, simple, chemical ion exchange method at room temperature on ITO glass substrate. The as-grown varying composition solar cells annealed at 200degreeC in air and characterized for structural, compositional, optical and illumination studies. The X-ray diffraction pattern obtained from CdS/CuInSXSe2-X solar cell confirms the formation of CuInSe2, CuInS0.5Se1.5, CuInS1Se1, CuInS1.5Se0.5 and CuInS2 phases having tetragonal structure with varying crystallite size from 19, 19.37, 28, 33 and 20nm respectively. The energy dispersive X-ray analysis (EDAX) confirms the expected elemental com...

2011-01-01

416

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 finding cannot be said to be evidence against ...

2010-08-25

417

Performance testing of selected types of electronic personal dosimeters used in Sudan  

International Nuclear Information System (INIS)

Measurements were carried out for calibration and performance testing of a set of 10 electronic personal dosimeters (EPDs) at the Secondary Standard Dosimetry Laboratory of Sudan. Calibrations were carried out at three X-ray beam qualities described in ISO standard 4037 in addition to 137Cs and 60Co gamma ray beams. The experimental was performed with EPDs mounted on ICRU Slab phantom. X-ray and ?-ray beams were characterized in terms of air kerma free-in-air which were converted to the known delivered personal dose equivalent, Hp(10) using appropriate the air kerma to personal dose equivalent conversion coefficients. Dosimeters tested showed excellent energy and angular response and relative error of indication within the recommended limit for photon energies from 65 keV to 1.25 MeV. The study showed encouraging results for using electronic dosimeters in personal dosimetry.

2010-12-01

418

Passivity of 316L stainless steel in borate buffer solution studied by Mott-Schottky analysis, atomic absorption spectrometry and X-ray photoelectron spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} The polarization curve of 316L SS possesses five turning potentials in passive region. {yields} Films formed at turning potentials perform different electrochemical and semiconductor properties. {yields} Dissolutions and regenerations of passive film at turning potentials are obtained by AAS and XPS. {yields} Turning potentials appearing in passive region are ascribed to the changes of the compositions of the passive films. - Abstract: The passivity of 316L stainless steel in borate buffer solution has been investigated by Mott-Schottky, atomic absorption spectrometry (AAS) and X-ray photoelectron spectroscopy (XPS). The results indicate that the polarization curve in the passive region possesses several turning potentials (0 V{sub SCE}, 0.2 V{sub SCE}, 0.4 V{sub SCE}, 0.6 V{sub SCE} and 0.85 V{sub SCE}). The passive films formed at turning potentials perform different electrochemical and semiconductor properties. Further, the ...

2010-11-15

419

PET/MRI hybrid imaging: devices and initial results  

International Nuclear Information System (INIS)

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

2008-06-01

420

Nature of magnetic coupling between Mn ions in as-grown Ga1-xMnxAs studied by x-ray magnetic circular dichroism  

International Nuclear Information System (INIS)

The magnetic properties of as-grown Ga1-xMnxAs have been investigated by the systematic temperature and magnetic field dependent soft x-ray magnetic circular dichroism (XMCD) measurements in the Mn L2,3 absorption edge region. The XMCD intensity at high temperatures obeys the Curie-Weiss law, but residual spin magnetic moment appears already around 100 K, significantly above Curie temperature (Tc), suggesting that short-range ferromagnetic correlations are developed significantly above Tc. The high-field magnetic susceptibility becomes T-independent below TC, indicating that the AF interaction between the substitutional Mn (Mnsub and interstitial Mn (Mnint) ions, which becomes strong as the Mn concentration x increases, exists and that the amount of the Mnint affects Tc. The present experimental findings should give valuable insight into the inhomogeneous magnetic properties of many DMS's. (author)

2009-07-01

421

Masses of Neutron Stars in High-Mass X-ray Binaries with Optical Astrometry  

CERN Document Server

Determining the type of matter that is inside a neutron star (NS) has been a long-standing goal of astrophysics. Despite this, most of the NS equations of state (EOS) that predict maximum masses in the range 1.4-2.8 solar masses are still viable. Most of the precise NS mass measurements that have been made to date show values close to 1.4 solar masses, but a reliable measurement of an over-massive NS would constrain the EOS possibilities. Here, we investigate how optical astrometry at the microarcsecond level can be used to map out the orbits of High-Mass X-ray Binaries (HMXBs), leading to tight constraints on NS masses. While previous studies by Unwin and co-workers and Tomsick and co-workers discuss the fact that the future Space Interferometry Mission should be capable of making such measurements, the current work describes detailed simulations for 6 HMXB systems, including predicted constraints on all orbital parameters. We find that the ...

2010-01-01

422

Line intensity enhancements in stellar coronal X-ray spectra due to opacity effects  

CERN Document Server

Context. The I(15.01 A)/I(16.78 A) emission line intensity ratio in Fe XVII has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 A line, leading to a reduction in its intensity, and was interpreted in terms of a geometry in which the emitters and absorbers are spatially distinct. Aims. We study the I(15.01 A)/I(16.78 A) intensity ratio for the active cool dwarf EV Lac, in both flare and quiescent spectra. Methods. The observations were obtained with the Reflection Grating Spectrometer on the XMM-Newton satellite. The emission measure distribution versus temperature reconstruction technique is used for our analysis. Results. We find that the 15.01 A line exhibits a significant enhancement in intensity over the optically thin value. To our knowledge, this is the first time that such an enhancement has been detected on such a sound statistical basis. We interpret ...

2008-01-01

423

K{beta}-to-K{alpha} X-ray intensity ratio studies on the changes of valence electronic structures of Ti, V, Cr, and Co in their disilicide compounds  

Energy Technology Data Exchange (ETDEWEB)

K{beta}-to-K{alpha} X-ray intensity ratios of Ti, V, Cr, and Co in pure metals and their disilicide compounds have been measured following excitation by 59.54 keV {gamma}-rays from a 200 mCi {sup 241}Am point-source. The K{beta}-to-K{alpha} intensity ratios of all these metals in the disilicide compounds are found to be less than the corresponding ratios for pure metals. Comparison of the measured K{beta}-to-K{alpha} intensity ratios for the disilicides and pure metals with the multiconfiguration Dirac-Fock calculations indicates increase of the 3d electron populations of Ti, V, Cr, and Co in the disilicides from their pure metal values suggesting the rearrangement of electrons between 3d and 4s states of the individual metal atom. This rearrangement is found to be opposite to that observed in our previously reported work on NiSi{sub 2} and CuSi{sub 2}.

1999-06-01

424

K#beta#-to-K#alpha# X-ray intensity ratio studies on the changes of valence electronic structures of Ti, V, Cr, and Co in their disilicide compounds  

International Nuclear Information System (INIS)

K#beta#-to-K#alpha# X-ray intensity ratios of Ti, V, Cr, and Co in pure metals and their disilicide compounds have been measured following excitation by 59.54 keV #gamma#-rays from a 200 mCi "2"4"1Am point-source. The K#beta#-to-K#alpha# intensity ratios of all these metals in the disilicide compounds are found to be less than the corresponding ratios for pure metals. Comparison of the measured K#beta#-to-K#alpha# intensity ratios for the disilicides and pure metals with the multiconfiguration Dirac-Fock calculations indicates increase of the 3d electron populations of Ti, V, Cr, and Co in the disilicides from their pure metal values suggesting the rearrangement of electrons between 3d and 4s states of the individual metal atom. This rearrangement is found to be opposite to that observed in our previously reported work on NiSi_2 and CuSi_2.

1999-06-01

425

Inverse spinel materials. A new class of high voltage cathode materials for Li-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

The influence of Cr on the structure and electrochemical properties of LiCoVO{sub 4} was studied using X-Ray diffraction, scanning electron microscopy, Raman Spectroscopy and cycle tests. Doping levels up to 10 mol% were achieved, which improved the electrochemical stability of the structure of LiCoVO{sub 4}, resulting in a significant increase in the initial charge and discharge capacity. The Raman spectroscopy data for the Cr-doped LiCoVO{sub 4} is similar as for LiCoVO{sub 4}. The replacement of a dopant for the Co-ion in the inverse spinel structure causes several Raman shifts. The X-ray diffraction patterns show no new phases and combined with the Raman spectroscopy data it is concluded that the Cr dopant will be located at the octahedral site (16d) where they create an electronic pathway that enhances the electronic conductivity. However, the capacity dropped significantly after prolonged cycling, which is due to the ...

2003-07-01

426

High resolution computed tomography in the study of cervical spine trauma  

International Nuclear Information System (INIS)

Correct ortopedic therapy for traumas of the cervical rachis requires perfect knowledge of the spatial balance of the fracture focus. The authors belive Computed Tomography (CT) to be the most suitable, and often indispensable, method for this purpose. Twenty-four patients were examined for traumatic pathology of the cervical rachis. In 7 cases with clinically minor traumas, the negative outcome of the traditional traumas, the negative outcome of the traditional exam was considered reliable and sufficient for therapeutic purposes. The extant 17 patients were examined also by means of CT, either to better dermine the characteristics of skeletal lesions already ascertained with traditional techniques or to asses the presence of clinically-suspected osteo-articular lesions, even with negative conventional X-rays. For 9 of these patients orthopedic treatment was considered sufficient, whereas 8 patients underwent surgery and were subsequently examined with CT, which ...

1989-01-01

427

Evaluation of selective alveolo-bronchography with Fuji computed radiography and x-ray CT  

International Nuclear Information System (INIS)

Selective alveolo-bronchography (SAB) has been routinely used to evaluate anatomical changes in the bronchiole and its distal air spaces. A narrowing of the bronchiole and abnormal pooling of contrast medium in the destroyed air space are the prime findings. Since the object of radiography is extremely thin, direct magnification radiography is mandatory to obtain radiologic details. However, the problem with this technique is that radiographic quality varies depending upon the size of the patient and the concentration of contrast medium to be introduced in the lung. This study had two goals. One was to improve the image quality of SAB by Fuji Computed Radiography (FCR). FCR provides radiographs with a good contrast and stable density throughout a wide range of exposure factors which occur in the use of SAB. The other goal was to separately evaluate morphological abnormalities in the outer and inner zones of the lung using X-ray CT. This idea ...

1986-01-01

428

Effects of post-irradiation annealing in alpha-particle bombarded molybdenum  

International Nuclear Information System (INIS)

Structural variations in 39-MeV alpha-particle irradiated (Tsub(irr) = 60 deg C) polycrystalline molybdenum during post-irradiation annealing were studied by X-ray and TEM methods. Despite the high density of irradiation induced defects in the structure of the specimen X-ray measurements showed zero relative lattice parameter change after an irradiation dose of 1.1 x 10"-_2 dpa. However, during the annealing #delta#a/a was changed in the positive range, exhibiting two peaks - at 100 and 300 deg C - whereas the damage structure detected by TEM indicated no changes. Analysis of the results leads to the conclusion that in the range 100 to 250 deg C migration of isolated vacancies and their annihilation at interstitial clusters as well as possible formation of new vacancy clusters occur. The second peak on the #delta#a/a temperature dependence curve is related to the transformation (probably, thermal disintegration) of vacancy ...

429

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 ...

1990-01-01

430

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, ...

1990-05-01

431

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, ...

1990-05-01

432

Coal demineralization with Ca(OH)2. Hydrothermal reaction between Ca(OH)2 and quartz; Ca(OH)2 wo mochiita sekitan no kagakuteki dakkai. Ca(OH)2 to sekitan no suinetsu hanno  

Energy Technology Data Exchange (ETDEWEB)

Coal demineralization mechanism and its optimum condition were studied by hydrothermal reaction between Ca(OH)2 and quartz as a coal demineralization model. In experiment, the mixture of powder quartz and Ca(OH)2 water slurry was subjected to reaction in an autoclave under spontaneous pressure at 175-340{degree}C. After dried in N2 gas atmosphere at 105{degree}C, the reaction product was analyzed by X-ray diffraction, thermo-balance and differential thermal analysis. In measurement of quartz conversion, the specimen was analyzed by X-ray diffraction after removal of bound water by heat treatment at 850{degree}C. The mixture of clean coal deashed by NaOH and a fixed amount of quartz was also used as specimen for experiment. As the experimental result, dicalcium silicate hydrate was mainly produced at 175{degree}C, and the product changed into xonotlite through tobermorite by longer treatment at higher temperature. For ...

1996-10-28

433

Charge redistribution in ion-beam-mixed Pd-Ag alloys  

Science.gov (United States)

Charge flow and valence/d-band behavior in ion-beam-mixed (IBM) Pd1-xAgx (x = 0.5-0.9) alloys have been studied by X-ray photoemission measurement of the valence bands and of core-level binding energy shifts and X-ray absorption near-edge structure. We correlated the observed Ag 3d5/2 core-level shifts in these IBM alloys, relative to the elemental Ag, with the White Line area changes at the Pd and Ag L3-edge to investigate the charge redistribution at the Ag site. The results indicate that there is a decrease in sp-like conduction electron and a negligible change in the number of d-electrons at the Ag site upon alloying. These results are in line with our previous results in which Pd gains d-charges and loses sp-type charges. This electron redistribution due to hybridization in the alloy leads small net charge transfer from the Ag site to the Pd site in accordance with electronegativity predictions. This result is ...

1996-08-01

434

Characterization and reactivity of Fe3O4/FeMnOx core/shell nanoparticles for methylene blue discoloration with H2O2  

British Library Electronic Table of Contents (United Kingdom)

A magnetic core/shell Fe3O4/FeMnOx catalyst was prepared by a simple oxidation-precipitation method. The catalyst was characterized by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and cyclic voltammetry. The characterization studies verified that Fe3O4 core was coated with a layer of Fe-Mn oxide. The Fe3O4/FeMnOx was found to be an effective and stable heterogeneous catalyst for the discoloration of methylene blue (MB) in aqueous solution by H2O2. The high catalytic activity is due to the FeMnOx shell, which not only increased the surface hydroxyl groups, but also enhanced the interfacial electron transfer. The discoloration of MB could be due to the decomposition of H2O2 into ?OH ...

2011-01-01

435

Broad-band stigmatic spectrograph for the soft x-ray range  

International Nuclear Information System (INIS)

We describe a panoramic stigmatic spectrograph comprising a grazing-incidence toroidal mirror and a large-aperture free-standing transmission diffraction grating (5000 lines mm-1 ). Two spectrograph versions were constructed, with grazing angles of 7.6 and 40 and the short-wavelength spectral limits near 4 and 1.5 nm. The spectrograph aberrations were studied by numerical ray tracing. The spectrograph was used to record line and quasi-continuous spectra (1.5 - 30 nm) of multiply charged ions in a plasma generated by the second-harmonic pulses of an yttrium aluminate laser (Q = 0.15 J, ? = 5 ns, ? = 0.54 ?m, repetition rate = 0.5 Hz). In combination with a laser-produced plasma radiation source, the arrangement was used to characterise soft x-ray optical components and to generate collimated beams of polarised radiation in the 14 - 20 nm range. (laser applications and other topics in quantum electronics)

1998-09-30

436

Application of spectroscopic techniques for the study of paper documents: A survey  

International Nuclear Information System (INIS)

For many centuries paper was the main material for recording cultural achievements all over the world. Paper is mostly made from cellulose with small amounts of organic and inorganic additives, which allow its identification and characterization and may also contribute to its degradation. Prior to 1850, paper was made entirely from rags, using hemp, flax and cotton fibres. After this period, due to the enormous increase in demand, wood pulp began to be commonly used as raw material, resulting in rapid degradation of paper. Spectroscopic techniques represent one of the most powerful tools to investigate the constituents of paper documents in order to establish its identification and its state of degradation. This review describes the application of selected spectroscopic techniques used for paper characterization and conservation. The spectroscopic techniques that have been used and will be reviewed include: Fourier-Transform Infrared spectroscopy, Raman spectroscopy, Nuclear Magnetic ...

2009-06-01

437

Analysis on Dose Distribution in Heterogeneous Condition for Narrow 6 MV X-ray Beams  

International Nuclear Information System (INIS)

Advanced modality of high-precision radiotherapy fulfilled by a composition of large numbers of small field beams called 'beamlets' can be achieved via nonuniform intensity fluencies. In case of radiation measurements and calculations with narrow high-energy photon beams, however, an accurate two-dimensional dosimetry is a challenging task due to dosimetrically unfavorable phenomena such as dramatic changes of the dose at the field boundaries, dis-equilibrium of the electrons resulting from larger detector volume, and non-uniformity between the detector and the phantom materials. Meanwhile, with the advantages of high spatial resolution and wide range of absorbed doses, there is a growing demand of GAFCHROMICat..EBT film to confirm delivered dose distribution. Especially, the effects from the material differences between the phantom and the film can be minimized in the heterogeneous condition since the GAFCHROMICat..EBT film is composed of tissueequivalent materials. In the present ...

2010-10-01

438

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 ...

2008-07-14

439

ESR study of X-ray irradiated rare earth (Ln) ion-doped glaserite and Ln ion-doped langbeinite  

Energy Technology Data Exchange (ETDEWEB)

X-ray irradiation-induced paramagnetic radicals in rare earth (Ln) ion-doped glaserite and Ln ion-doped langbeinite were studied by means of ESR technique, aiming at developing the highly sensitive sensor for an ESR dosimetry. The samples were prepared by two kinds of procedures as follows. In one process, the glaserite (K{sub 3}Na(SO{sub 4}){sub 2}) matrix or the langbeinite (K{sub 2}Mg{sub 2}(SO{sub 4}){sub 3}) matrix were synthesized by heating the mixture of K{sub 2}SO{sub 4} and Na{sub 2}SO{sub 4} or the mixture of K{sub 2}SO{sub 4} and MgSO{sub 4} at 1023 K for 1 hour in He flow. The matrices obtained were mixed well with a fixed amount of Ln{sub 2}(SO{sub 4}){sub 3} (Ln=La, Eu, Gd, Lu) powder and heated at 1023 K for 1 hour in He flow. In the other process, the homogeneous mixture of a fixed amount of K{sub 2}SO{sub 4}, Na{sub 2}SO{sub 4} and Ln{sub 2}(SO{sub 4}){sub 3} powders or a fixed amount of K{sub 2}SO{sub 4}, MgSO{sub 4} and ...

1992-06-01

440

X-ray absorption spectroscopy of bacterial sulfur globules  

Energy Technology Data Exchange (ETDEWEB)

Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favorable circumstances the technique can provide quantitative information on the chemical identify of the sulfur species that are present in a sample. Prange et al. have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, they contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al. employed a curve-fitting method similar to that used by us (for more than 10 years). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown, in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur ...

2002-08-01

441

Study of osteoporosis using dual energy X-ray absorptiometry  

Energy Technology Data Exchange (ETDEWEB)

Dual energy X-ray absorptiometry (Hologic QDR-1000) was used to quantitatively analyze the diagnosis and prevention of osteoporosis. The peak bone mineral density (BMD) of the spine appeared in normal men in their twenties and in normal women in their thirties. There was acceleration of bone loss in the 50 to 60 year age bracket (premenopause and postmenopause) in normal women. On the contrary, the peak BMD of the femoral neck in normal men and women appeared in their twenties after which it decreased slightly with age. Comparison showed that the femoral neck BMD of normal women was lower than that of men throughout all ages. The fracture threshold, 0.756 g/cm[sup 2] for the spine, was obtained by scanning 73 females with spinal fractures, the mean BMDs for L2-L4 at the 90th percentile level were used as the fracture threshold. The fracture threshold of femoral neck fracture was the femoral proximal BMD of the 9th decile. Classification by the Public Welfare Silver ...

1992-04-01

442

Gene rearrangement and radiation carcinogenesis  

International Nuclear Information System (INIS)

The development of leukemia and thyroid cancer is characterized by activation of the abl oncogene and ret oncogene, respectively. In order to clarify the relationship between these gene aberrations and radiation, the pro-myelogenous leukemia-derived cell line HL60 and the thyroid cancer-derived cell line 8505C, were irradiated in vitro with 100Gy of X-rays. RNA was then extracted from 10"8 cells of the respective cell lines and examined by the reverse transcription PCR method for rearrangements of abl and ret genes. Five kinds of positive bands were observed in the HL-60 cells irradiated with 100Gy of X-ray. Similarly, six positive bands were also observed in the 8505C cells irradiated with 100Gy. In vitro X-irradiation activation of oncogenes found in radiation induced cancers imply that gene rearrangement by X-rays is involved in the development of malignant tumors. Furthermore, in an experiment to detect radiation ...

1993-11-01

443

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

Energy Technology Data Exchange (ETDEWEB)

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

1989-06-01

444

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

International Nuclear Information System (INIS)

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

1989-01-01

445

Analyses of superficial and depth doses in intraoral radiology  

Energy Technology Data Exchange (ETDEWEB)

In this work dosimetric analysis using thermoluminescence technique to study the beams characteristics of x-rays employed in dental radiology has been carried out. The obtained results with CaSO{sub 4}:Dy thermoluminescent dosimeters (TLD) were compared to the doses obtained with parallel-plates ionization chamber. Dosimetric evaluations were also done using radiographic films of large dimensions. The x-rays equipments analyzed were installed in the radiological services of Odontology Department of Sergipe Federal University (U.F.S.). Depending on the anatomical region to be examined the proper exposure time was select, for a fix voltage of 70 kV. The results with TLD and ionization chamber have been determined to female and male individuals. The intraoral regions analysed were the peri apical of the incisors, molar and pre-molar teeth and the occlusive region. These regions were simulated using acrylic plates absorbers ...

2006-07-01

446

Rubidium 5"2P fine-structure transitions induced by collisions with potassium and caesium atoms  

International Nuclear Information System (INIS)

A diode-laser fluorescence experiment was performed in order to study fine-structure transitions between 5"2P states of rubidium atoms colliding with ground-state potassium or caesium atoms. The Rb(5"2P_3_/_2) state was optically excited and the intensity ratio of sensitized to direct fluorescence was measured. (author).

447

Determination of radiation exposure and significance of its influential factors for X-rayed children in the GDR  

International Nuclear Information System (INIS)

After having discussed the peculiarities of children in X-ray diagnosis the application of the effective as well as the mean equivalent doses as to the determination of the radiation exposure in children is represented. In using computerized tomograms to determine position and extent of an organ the exposure by repeated X-raying was calculated referring to the entrance dose. Entrance dose measurements for all types of X-ray examination in hospitals and ascertainments of the frequency of radiograms in 20 X-ray departments were used to determine per capita and collective doses, resp., in several age groups. Alltogether, the per capita dose of children in the GDR amounts to 30% of that of adults. Conclusions were drawn as to taking measures to further reduction of radiation exposure: (1) Technical measures, such as positioning of patients, shielding of organs, quality assurance; (2) elaboration of ...

1988-01-01

448

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

449

Strain evolution in Si substrate due to implantation of MeV ion observed by extremely asymmetric x-ray diffraction  

International Nuclear Information System (INIS)

We studied the strain introduced in a Si(111) substrate due to MeV ion implantation using extremely asymmetric x-ray diffraction and measured the rocking curves of asymmetrical 113 diffraction for the Si substrates implanted with a 1.5 MeV Au"2"+ ion at fluence values of 1x10"1"3, 5x10"1"3, and 1x10"1"4/cm"2. The measured curves consisted of a bulk peak and accompanying subpeak with an interference fringe. The positional relationship of the bulk peak to the subpeak and the intensity variation of those peaks with respect to the wavelengths of the x rays indicated that crystal lattices near the surface were strained; the lattice spacing of surface normal (111) planes near the surface was larger than that of the bulk. Detailed strain profiles along the depth direction were successfully estimated using a curve-fitting method based on Darwin's dynamical diffraction theory. Comparing the shapes of resultant ...

2009-08-15

450

Micro area analysis and measurement of electronic device material (challenge to utmost limits). Characterization of interface elect`ron structure by photon-and electron-spectroscopies; Denshi debaisu yo zairyo no bisho ryoiki bunseki-keisoku (kyokugen eno chosen). Koshi-denshi bunkoho ni yoru kaimen denshi jotai hyoka  

Energy Technology Data Exchange (ETDEWEB)

A method for detecting electrons emitted as secondary particles by photon incidence to a specimen, as well as a method of using the photons emitted by electron incidence as detecting particles are explained. Pd-Si(100)2{times}1 system is adopted for a case study of using photo-electron spectroscopy where synchrotron emitted light in soft X-ray region is used as the incident light. Pd atoms are deposited little by little on clean Si surface to investigate the electron structure of the surface, and the interface electron structure after bonded formation of Pd(thin film)-Si(substrate) is estimated. Radiation soft X-ray spectroscopy is employed to observe the real state of the bonded interface of Pd(thin film)-Si(substrate) prepared by depositing Pd film in a short period of time. In the case of radiation soft X-ray spectroscopy with electron beam excitation, bonded system of thin film and substrate can be ...

1995-07-20

451

Dosimetry measurements of x-ray and neutron radiation levels near the shuttle and end beam dump at the advanced test accelerator: Beam Research Program  

International Nuclear Information System (INIS)

Electron beams as a source of directed energy are under study at the Lawrence Livermore National Laboratory (LLNL). An intense 10-kA, 50-MeV, 50-ns full-width half-maximum, pulsed electron beam is generated by the prototype Advanced Test Accelerator (ATA) at the Laboratory's Site 300. Whenever the electron beam is stopped in materials, intense radiation is generated. Estimates based on available data in the literature show that for materials such as lead, photon radiation (x ray, gamma, bremsstrahlung) levels can be as large as 10"4 roentgens per pulse at 1 m in the zero-degree direction (i.e., the electron-beam direction). Neutrons, which are emitted isotropically, are produced at a level of 10"1"3 n/m"2 per pulse. Depending upon the number of pulses and the shielding geometry, the accumulated dose is potentially lethal to personnel and potentially damaging to instrumentation that may be used for diagnostics. To provide ...

452

Anode length optimization in a modified plasma focus device for optimal x-ray yields  

International Nuclear Information System (INIS)

The effect of anode length and operating gas pressure on the x-ray emission from a nitrogen-filling modified plasma focus device has been investigated. The time-resolved investigation of x ray was carried out by using a five-channel photodiode x-ray spectrometer. The maximum x-ray yield is seen to increase with the increase in the anode length from 110 to 125 mm. Further increase in the anode length to 130 mm causes the x-ray yields to decrease. The highest x-ray yield of 4.5 J into 4#pi# sr was found for 125 mm anode length, which is 0.2% of the input energy. The average x-ray photon energy was estimated by using half-value thickness method and found to be 8.4 keV. The electron temperature of the plasma was estimated to be around 3 keV by x-ray intensity ratio method. The space-resolved ...

2006-01-01

453

Thermo-transferred thermoluminescence (TTTl) in potassium-yttrium double fluoride doped with terbium  

International Nuclear Information System (INIS)

This paper presents results of studying the thermo-transferred thermoluminescence (TTTl) phenomenon in potassium-yttrium double fluoride doped with terbium (K_2YF_5_:Tb) at different impurity concentrations (0.8%, 0.95% and 0.99%). Previously to study the TTTl phenomenon, structural characterization and chemical composition of the materials were determined. The structural studies were conducted using a scanning electron microscope; meanwhile, chemical composition was analyzed using energy dispersive X-ray spectroscopy. Thermoluminescence kinetics was studied irradiating the samples with "1"3"7Cs gamma rays as well as with "9"0Sr/"9"0Y beta rays, analyzing the glow curves by the deconvolution method for obtaining the kinetic parameters. (Author)

2011-02-01

454

The segmental gastrocnemius muscles' flap: A cadaveric study  

British Library Electronic Table of Contents (United Kingdom)

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

2011-01-01

455

Time-resolved confocal fluorescence spectroscopy reveals the structure and metabolic state of epithelial tissue  

Science.gov (United States)

Autofluorescence spectroscopy has been a widely explored technique for in vivo and noninvasive diagnosis of pre-cancer lesions in epithelium where 90% cancers originate. For extracting more accurate fluorescence information for cancer diagnosis, depth-resolved fluorescence measurements are crucial to assess NADH and FAD in non-keratinized epithelial layer and collagen in stromal layer, respectively. In this study, we achieved the depth-resolved fluorescence spectral measurements of squamous epithelial tissue based on confocal technique. We found that in non-keratinized epithelial layer the fluorescence signals excited at 405 nm were the combination of NADH and FAD fluorescence and could be used for evaluating the redox ratio. Moreover, we found that confocal time-resolved autofluorescence measurements of epithelial tissue with 405 nm excitations could provide ...

2007-03-01

456

DoseWatchers - A computer based X ray dose monitoring project in paediatric radiology  

International Nuclear Information System (INIS)

Full text: Introduction. Children, especially premature infants and neonates, are at a much higher risk to obtain an X ray induced disturbance of life - particularly cancer. On the one hand this is due to their longer life expectancy and on the other hand it is due to their higher cell proliferation rate. The paediatric radiology unit of the Inselspital Bern recently installed some of the most advanced X ray equipment nowadays available. It is based on the two latest digital technologies: double read computed radiography (CR) and direct digital radiography (DR). Only the implementation of these digital radiography systems permits the digital acquisition and additionally the analysis of acquired data. The systematic analysis of large amounts of biometric data and exposition data is the basis for further dose reduction and a systematic quality control (QC). Patients are increasingly critical concerning ...

2006-11-13

457

Detection of Fluorescence for Lanthanides in LiCl-KCl Molten Salt Medium  

Energy Technology Data Exchange (ETDEWEB)

In the electrorefining step of the pyrochemical process, actinide ions dissolved in the LiCl-KCl eutectic salt are recovered as pure actinide metals at a cathode for a re-use as a nuclear fuel from the aspect of its nonproliferation of the nuclear fuel cycles. The lanthanide species dissolved in the LiCl-KCl eutectic salt play an important role in an effective metal purification during the electrorefining step, so it is necessary to understand the chemical and physical behaviors of lanthanides in molten salt. The in situ spectroscopic measurement system and studies according to temperature changes are essential for better understandable information. To our knowledge, the absorption studies of lanthanides at high temperatures have been reported before, but the fluorescence studies of those at high temperature are not reported yet. We will discuss here the fluorescence behaviors of ...

2007-10-15

458

Detection of Fluorescence for Lanthanides in LiCl-KCl Molten Salt Medium  

International Nuclear Information System (INIS)

In the electrorefining step of the pyrochemical process, actinide ions dissolved in the LiCl-KCl eutectic salt are recovered as pure actinide metals at a cathode for a re-use as a nuclear fuel from the aspect of its nonproliferation of the nuclear fuel cycles. The lanthanide species dissolved in the LiCl-KCl eutectic salt play an important role in an effective metal purification during the electrorefining step, so it is necessary to understand the chemical and physical behaviors of lanthanides in molten salt. The in situ spectroscopic measurement system and studies according to temperature changes are essential for better understandable information. To our knowledge, the absorption studies of lanthanides at high temperatures have been reported before, but the fluorescence studies of those at high temperature are not reported yet. We will discuss here the fluorescence behaviors of ...

2007-10-01

459

X-Ray Phase Imaging for Breast Cancer Detection  

Science.gov (United States)

... Accession Number : ADA535309. Title : X-Ray Phase Imaging for Breast Cancer Detection. Descriptive Note : Annual rept. 1 Sep 2009-31 Aug 2010 ...

2010-09-01

460

Subacute neuropathological effects of microplanar beams of x-rays from a synchrotron wiggler.  

UK PubMed Central (United Kingdom)

Microplanar beam radiation therapy has been proposed to treat brain tumors by using a series of rapid exposures to an array of parallel x-ray beams, each beam having uniform microscopic thickness and...Full Text Available

1995-09-12

461

Small-Angle X-ray Scattering of Reduced Ribonuclease A: Effects of Solution Conditions and Comparisons with a Computational Model of Unfolded Proteins  

UK PubMed Central (United Kingdom)

The disulfide-reduced form of bovine ribonuclease A (RNAse A), with the Cys thiols irreversibly blocked, was characterized by small-angle x-ray scattering (SAXS). To help resolve the conflicting...Full Text Available

2008-04-11

462

Radiation exposure due to X-rays of the hip joint in babies  

International Nuclear Information System (INIS)

Exact anatomic knowledge about the location of the gonads and the application of corresponding measures of radiation protection are the preconditions for an efficient reduction of the danger of a possible genetic damage as a result of radiation exposition during X-ray examination of the hip joint of newborns. (VJ).

463

PIXE analysis of GaAs and ZnSe  

Energy Technology Data Exchange (ETDEWEB)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K{sub {alpha}} X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K{sub {alpha}} X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the ...

1990-01-01

464

PIXE analysis of GaAs and ZnSe  

International Nuclear Information System (INIS)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K_#alpha# X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K_#alpha# X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the ...

1989-06-01

465

Numerical optimization of spherical variable-line-spacing grating X-ray spectrometers  

UK PubMed Central (United Kingdom)

Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and...Full Text Available

2011-03-01

466

Method of describing dose distributions in computer design of teleradiotherapy  

International Nuclear Information System (INIS)

Method for description of X-ray radiation dose distribution based on semiempirical description of dose fields is suggested. At that dose field description parameters can be easily individualized for concrete X-ray device.

467

Measurements of accurate x-ray scattering data of protein solutions using small stationary sample cells  

UK PubMed Central (United Kingdom)

In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage...Full Text Available

2009-01-01

468

Magnetic fields of x-ray pulsars  

Energy Technology Data Exchange (ETDEWEB)

An analytic model of magnetic torques applied to an accreting neutron star is employed to evaluate the magnetic dipole moments of x-ray pulsars. A new type of close binary system containing a neutron star is suggested.

1982-09-01

469

Grating-based X-ray phase imaging using multiline X-ray source  

International Nuclear Information System (INIS)

Differential phase-contrast X-ray imaging has been performed in a Talbot-Lau configuration, where a multiline X-ray source was used instead of a combination of a hard-X-ray multiple slit and a normal focus X-ray generator. When the multiple slit is used, a high aspect ratio structure is needed and slit width should be below 10 ?m for its function. The fabrication and use of such a multislit can be omitted using the presented configuration. The multiline X-ray source was developed by making grooves on a tungsten rotating anode, which was irradiated by an electron beam to generate X-rays. An array of 10?m line sources with a pitch of 30?m was formed and combined with a 4.5 ?m pitch phase grating and a 5.3 ?m pitch amplitude grating to generate differential phase contrast. With a total exposure time of 40 s, a differential phase image depicting cartilages was ...

2009-07-01

470

Experimental X-ray intensity ratio L#beta#/L#alpha#  

International Nuclear Information System (INIS)

Experimental, relative intensities for the components of L X-ray were collected from literature, and atomic-number dependency of L#beta#/L#alpha# has been found. (author).

1980-01-01

471

Complex Spatio-Spectral Structure of Diffuse X-Ray emission in the ...  

Science.gov (United States)

SN 1987A: Soft X-Ray Intensity Ratio. 2002-12 to 2000-12. 2005-7 to 2002-12. Contours: 2002-12. (0.5 2 keV). (0.5 2 keV). Contours: 2005-7 ...

472

Chemical effects on K x-ray intensity ratios in chromium compounds  

International Nuclear Information System (INIS)

K_#beta#/ K_#alpha# x-ray intensity ratio of chromium were measured in different chromium compounds. The results show the variation of the intensity ratio as a function of the chemical environment around the metal ion. (author)

2003-02-10

473

Characterization and catalytic oxidation activity of uranium-bismuth mixed oxides  

International Nuclear Information System (INIS)

Bi-U mixed oxides were synthesized by two methods and characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The samples were tested for the catalytic oxidation of carbon monoxide by oxygen. A stepwise redox mechanism consistent with the kinetic results is proposed. (orig.).

474

APOD: 2002 July 11 - M51: X Rays from the Whirlpool  

Science.gov (United States)

picture will download the highest resolution version available. M51: X-Rays from the Whirlpool Credit: A. Wilson (UMD) et al., CXC, NASA Explanation: Fresh from yesterday's...

2011-10-07

475

Radiation treatment of medical devices and packaging materials. Pt. 1  

International Nuclear Information System (INIS)

The first part of the study contains a literature compilation of more than 50 original publications reporting the radiation induced effects in 17 different high polymer materials and glass which are relevant in the manufacturing of medical devices or packing materials. The results collected demonstrate that high energy radiation, i.e. gamma- or X-rays, causes various physical and chemical alterations in high polymer materials. A detailed summary and discussion of the results of the original publications is not included in the present report, it will be presented in the second part of the study. Furthermore, the second part of the study will refer to the aspect of wholesomeness of irradiated medical devices or packing materials in a more general manner of representation. (orig.).

476

Microstructural aspects of the corrosion of Alloy 800  

International Nuclear Information System (INIS)

Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 #mu#m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl"- ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr"3"+ (as Cr_2O_3), without any Fe"3"+/Fe"2"+ or Ni"2"+. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.

2004-12-01

477

Adhesion studies of Au films on GaAs using ion-assisted deposition techniques  

International Nuclear Information System (INIS)

This paper reports on a series of experiments performed to examine the ability of ion beam assisted thermal deposition to produce good adhesion of Au metallization on GaAs left-angle 100 right-angle substrates. A study of the influence of Ar ion-assisted thermal deposition of the Au films as well as in situ pre-sputtering of the GaAs surface with low-energy Ar ions prior to thermal deposition, shows that strong adhesion can be achieved without resorting to chemical cleaning. The substrate temperature and the relative flux of Ar ions to incident Au atoms were varied in order to correlate these parameters with film adhesion. The interfaces of films processed under these various conditions were examined by XTEM, RBS and XPS. Orientation texture was studied by x-ray diffraction (XRD).

479

Superconducting properties of metallic superlattices  

Energy Technology Data Exchange (ETDEWEB)

The preparation by sputtering of artificial metallic superlattices is described, as are the results of x-ray structural determinations. Tunneling and resistivity measurements on these materials are reported.

1987-01-01

480

Plasma diagnostics in the optical and X-ray regions on the plasma focus device PF-4 (TULIP)  

International Nuclear Information System (INIS)

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

2006-09-11

481

Hard X-ray phase imaging and tomography using a grating interferometer  

International Nuclear Information System (INIS)

An interferometric technique for hard X-rays is presented. It is based on two transmission gratings and a phase-stepping technique, and it provides separate radiographs of the phase and absorption profiles of bulk samples. Tomographic reconstruction yields quantitative three-dimensional maps of the X-ray refractive index and of the attenuation coefficient, with a spatial resolution down to a few microns. The method is mechanically robust, it requires little monochromaticity, and can be scaled up to large fields of view. These are important prerequisites for use with laboratory X-ray sources. Numerous applications ranging from wave front sensing to medical radiography are presently under investigation.

2007-07-01

483

Electron-induced luminescence and x-ray spectrometer development: progress report  

Science.gov (United States)

The progress in the development of a surface analysis tool based on the excitation of characteristic

2003-01-01

484

Electron-Induced Luminescence and X-Ray Spectrometer (ELXS) System for Life Detection  

Science.gov (United States)

The ELXS concept is a novel, portable, micro-instrument targeted for the detection of mineralogic

2002-01-01

485

Development of high resolution imaging detectors for X-ray astronomy  

Energy Technology Data Exchange (ETDEWEB)

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

1985-03-01

486

Development of high resolution imaging detectors for X-ray astronomy  

International Nuclear Information System (INIS)

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

1985-01-01

488

Luminescence of Strontianite (SrCO{sub 3}) from Strontian (Scotland, UK)  

Energy Technology Data Exchange (ETDEWEB)

An historic Strontianite-type specimen from Strontian, Scotland, UK, was characterized to broaden our knowledge on luminescence properties of common carbonates. These fibrous aggregates are Strontianite (Sr{sub x}Ca{sub 1-x}CO{sub 3}) with circa 6% of CaO, interfacial water, hydrosilicate anions and substitutional divalent cations, e.g., Ca{sup 2+}, Mn{sup 2+}, Fe{sup 2+} in structural Sr{sup 2+} positions. The specimen was analyzed by X-ray Fluorescence Spectrometry (XRF), Environmental Scanning Electron Microscopy coupled with an Energy Dispersive X-ray Spectroscopy (ESEM-EDS) probe, Spatially-resolved Cathodoluminescence under the Scanning Electron Microscope (SEM-CL), Differential-Thermal Analyses (DTA), Thermogravimetry (TG), Thermoluminescence (TL), Radioluminescence (RL) and High Resolution Spectra Thermoluminescence (3DTL), to gain an overview of the spectral emissions, the defect linkages were modified by heating ...

2009-04-15

489

X-ray findings in patients with miliary appearance of metallic mercury after suicide attempt  

Energy Technology Data Exchange (ETDEWEB)

This case report evaluates X-ray findings in patients with miliary accumulation of mercury observed after parenteral application of metallic mercury in a suizide attempt. There are certain discrepancies between clinical symptoms and the X-ray findings. A clear demonstration of mercury in coronary blood vessels is possible by fluoroscopy.

1985-03-01

490

The evolution of x-ray binaries  

International Nuclear Information System (INIS)

These proceedings represent papers presented at the Astrophysics Conference in Maryland, USA. The topic of the Conference was the evolution of x-ray binaries and the papers encompass a wide range of subjects on x-ray astronomy. There were one hundred eighteen papers presented at the Conference and out of these three have been abstracted for the Energy Science and Technology database.

1993-10-11

491

Quantitative phase imaging using hard x-rays  

International Nuclear Information System (INIS)

The quantitative imaging of a phase object using 16 keV x-rays is reported. The theoretical basis of the techniques is presented along with its implementation using a synchrotron x-ray source. It is found that the phase image is in quantitative agreement with independent measurements of the object. 13 refs., 5 figs.

2009-02-01

492

Pd-Na/F double exploding foil photoionization experiment  

Science.gov (United States)

The achievement of inner-shell photoionization of Zn-like Pd by means of two exploding foils is described. This resulted in the soft X-ray transition 3d94s2-3d104p at 46 A. It is shown that the photoionization of inner shell electrons in highly stripped ions can lead to X-ray transitions which may be candidates for X-ray lasers under 50 A.

1990-03-01

493

Multi-mirror system, 2. Application of inverse Compton Scattering for lithography X-ray sources  

Energy Technology Data Exchange (ETDEWEB)

A brilliant X ray source is proposed for lithography instruments with use of a multi-mirror system. The inverse Compton scattering between the stored electron beam in the storage ring and the stored photon beam in the multi-mirror system, is applied for the X-ray generation. (author)

2000-07-01

494

Measurement of the K?/K? ratio for muon alpha sticking X-rays in muon catalyzed d-t fusion at the RIKEN-RAL Muon Facility  

International Nuclear Information System (INIS)

At the RIKEN-RAL Muon Facility, ?- to ? sticking K? X-rays were observed for the first time taking advantage of the pulsed beam structure. The precision of the present measurements was insufficient to distinguish between theoretical models, however the observed K?/K? X-ray intensity ratio tends to be smaller than most of these theoretical predictions.

1999-06-01

495

From tomography to voludensitometry: radiation detectors for industrial control and medical instrumentation; De la tomographie a la voludensitometrie: les capteurs pour le controle industriel et l`instrumentation medicale  

Energy Technology Data Exchange (ETDEWEB)

In this article, the author presents the main technological solutions, available or in development, on X-ray detectors in order to obtain a digital image in biomedical radiography or in industrial radiography: linear x-ray detectors and bidimensional x-ray detectors (memory radioluminescent screens, matrix plan detectors).

1993-12-01

496

Mineralogical Data of Shocked Quartz Materials from K/T Boundary and Impact Crater  

Science.gov (United States)

Shocked quartz minerals from the Cretaceous-Tertiary (K/T) boundary and impact craters have been mainly discussed from distribution of optical directions, mean optical refractive index, and X-ray data (1). The purpose of the present study is presentation of the detailed mineralogical data of shocked quartz found in the K/T boundaries and terrestrial impact craters (2,3,4,5). X-ray powder diffraction pattern of shocked quartz aggregate reveals that all Xray peaks are split into major three peaks composed of low-density quartz (LQ), normal quartz (Q), and shocked quartz with high density (SQ). X-ray peaks of (110), (200), (201), (202), and (211) in the hexagonal cell are also split into many peaks. The X-ray intensity among LQ, Q, and SQ phases indicates that the SQ phase shows 36% to 53% in six K/T boundary samples (5). The relative X-ray intensity ratio of ...

1992-07-01