WorldWideScience

Sample records for resolved x-ray fluorescence

  1. Spatially resolved density and ionization measurements of shocked foams using x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, M. J.; Keiter, P. A.; Montgomery, D. S.; Scott, H. A.; Biener, M. M.; Fein, J. R.; Fournier, K. B.; Gamboa, E. J.; Kemp, G. E.; Klein, S. R.; Kuranz, C. C.; LeFevre, H. J.; Manuel, M. J. -E.; Wan, W. C.; Drake, R. P.

    2016-09-28

    We present experiments at the Trident laser facility demonstrating the use of x-ray fluorescence (XRF) to simultaneously measure density, ionization state populations, and electron temperature in shocked foams. An imaging x-ray spectrometer obtained spatially resolved measurements of Ti K-α emission. Density profiles were measured from K-α intensity. Ti ionization state distributions and electron temperatures were inferred by fitting K-α spectra to spectra from CRETIN simulations. This work shows that XRF provides a powerful tool to complement other diagnostics to make equation of state measurements of shocked materials containing a suitable tracer element.

  2. X-ray Fluorescence Sectioning

    CERN Document Server

    Cong, Wenxiang

    2012-01-01

    In this paper, we propose an x-ray fluorescence imaging system for elemental analysis. The key idea is what we call "x-ray fluorescence sectioning". Specifically, a slit collimator in front of an x-ray tube is used to shape x-rays into a fan-beam to illuminate a planar section of an object. Then, relevant elements such as gold nanoparticles on the fan-beam plane are excited to generate x-ray fluorescence signals. One or more 2D spectral detectors are placed to face the fan-beam plane and directly measure x-ray fluorescence data. Detector elements are so collimated that each element only sees a unique area element on the fan-beam plane and records the x-ray fluorescence signal accordingly. The measured 2D x-ray fluorescence data can be refined in reference to the attenuation characteristics of the object and the divergence of the beam for accurate elemental mapping. This x-ray fluorescence sectioning system promises fast fluorescence tomographic imaging without a complex inverse procedure. The design can be ad...

  3. X-ray fluorescence holography

    CERN Document Server

    Hayashi, K; Takahashi, Y

    2003-01-01

    X-ray fluorescence holography (XFH) is a new structural analysis method of determining a 3D atomic arrangement around fluorescing atoms. We developed an XFH apparatus using advanced X-ray techniques and succeeded in obtaining high-quality hologram data. Furthermore, we introduced applications to the structural analysis of a thin film and the environment around dopants and, discussed the quantitative analysis of local lattice distortion. (author)

  4. Filtered fluorescer x-ray detector

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, H.C.; Emig, J.A.; Thoe, R.S.; Springer, P.T.; Hernandez, J.A.

    1995-04-01

    Recently, an instrument capable of measuring x-rays between 8 and 90 keV was conceived to help understand conditions pertaining to pulsed power research. This resulted in the development of a versatile device that would incrementally detect x-rays emitted at predetermined energy bands over this range. To accomplish this, an array of well characterized filter-fluorescer combinations were produced which would allow fluoresced x-rays to be observed by time resolved electro-optical devices. As many as sixteen channels could be utilized with each channel having a corresponding background channel. Upon completion of the device, a three week series of experiments was then successfully carried out.

  5. Confocal depth-resolved fluorescence micro-X-ray absorption spectroscopy for the study of cultural heritage materials: a new mobile endstation at the Beijing Synchrotron Radiation Facility.

    Science.gov (United States)

    Chen, Guang; Chu, Shengqi; Sun, Tianxi; Sun, Xuepeng; Zheng, Lirong; An, Pengfei; Zhu, Jian; Wu, Shurong; Du, Yonghua; Zhang, Jing

    2017-09-01

    A confocal fluorescence endstation for depth-resolved micro-X-ray absorption spectroscopy is described. A polycapillary half-lens defines the incident beam path and a second polycapillary half-lens at 90° defines the probe sample volume. An automatic alignment program based on an evolutionary algorithm is employed to make the alignment procedure efficient. This depth-resolved system was examined on a general X-ray absorption spectroscopy (XAS) beamline at the Beijing Synchrotron Radiation Facility. Sacrificial red glaze (AD 1368-1644) china was studied to show the capability of the instrument. As a mobile endstation to be applied on multiple beamlines, the confocal system can improve the function and flexibility of general XAS beamlines, and extend their capabilities to a wider user community.

  6. Locally resolved investigation of wedged Cu(In,Ga)Se{sub 2} films prepared by physical vapor deposition using hard X-ray photoelectron and X-ray fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Calvet, Wolfram, E-mail: wolfram.calvet@helmholtz-berlin.de [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Ümsür, Bünyamin; Höpfner, Britta; Lauermann, Iver; Prietzel, Karsten; Kaufmann, Christan A.; Unold, Thomas [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Lux-Steiner, Martha C. [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Freie Universität Berlin, Department of Physics, Arnimallee 14, D-14195 Berlin (Germany)

    2015-05-01

    We have investigated a specially grown Cu(In,Ga)Se{sub 2} (CIGSe) absorber, which was deposited by co-evaporation of Cu, In, Ga, and Se using a modified three stage process. Prior to the growth, the molybdenum-coated glass substrate was covered by a bent shroud made from tantalum (Ta), leading to a wedged absorber structure with a width of about 2 mm where the film thickness varies from 0 to 2 μm. In this region of interest the thickness dependency of morphology, concentration ratios and electronic properties was studied with secondary electron microscopy (SEM), X-ray fluorescence (XRF) and hard X-ray photoelectron spectroscopy (HAXPES), probing the CIGSe sample along the thickness gradient. The evidence of the thickness gradient itself was proven with SEM measurements in cross section geometry. By using XRF it was found that with decreasing film thickness the Cu concentration decreases significantly. This finding was also verified by HAXPES measurements. Furthermore, an enrichment of Ga towards the Mo back contact was found using the same technique. Besides these results the formation of a molybdenum selenide (MoSe) phase was observed on the fully covered part of the Mo coated substrate indicating a high mobility of Se on Mo under the given temperature conditions of the modified three stage deposition process. - Highlights: • Growth of a CIGSe wedge • Application of HAXPES and XRF as local probing techniques • Good agreement with former studies • Wedged CIGSe structures can be used for further, locally resolved experiments.

  7. First X-ray fluorescence CT experimental results at the SSRF X-ray imaging beamline

    Institute of Scientific and Technical Information of China (English)

    DENG Biao; YANG Qun; XIE Hong-Lan; DU Guo-Hao; XIAO Wi-Qiao

    2011-01-01

    X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline (BL13W1) are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.

  8. X-ray microtome by fluorescence tomography

    CERN Document Server

    Simionovici, A S; Guenzler, F; Schrör, C; Snigirev, A; Snigireva, I; Tümmler, J; Weitkamp, T

    2001-01-01

    The X-ray fluorescence microtomography method is presented, which is capable of virtually slicing samples to obtain cross-sections of their inner structure. High precision experimental results of fluo-tomography in 'pencil-beam' geometry with up to 1.2 mu m resolution are described. Image reconstructions are based on either a simplified algebraic reconstruction method (ART) or the filtered back-projection method (FBP). Phantoms of inhomogeneous test objects as well as biological samples are successfully analyzed.

  9. Surface-Enhanced X-Ray Fluorescence

    Science.gov (United States)

    Anderson, Mark

    2010-01-01

    Surface-enhanced x-ray fluorescence (SEn-XRF) spectroscopy is a form of surface- enhanced spectroscopy that was conceived as a means of obtaining greater sensitivity in x-ray fluorescence (XRF) spectroscopy. As such, SEn-XRF spectroscopy joins the ranks of such other, longer-wavelength surface-enhanced spectroscopies as those based on surface-enhanced Raman scattering (SERS), surface-enhanced resonance Raman scattering (SERRS), and surfaceenhanced infrared Raman absorption (SEIRA), which have been described in previous NASA Tech Briefs articles. XRF spectroscopy has been used in analytical chemistry for determining the elemental compositions of small samples. XRF spectroscopy is rapid and quantitative and has been applied to a variety of metal and mineralogical samples. The main drawback of XRF spectroscopy as practiced heretofore is that sensitivity has not been as high as required for some applications. In SEn-XRF as in the other surface-enhanced spectroscopies, one exploits several interacting near-field phenomena, occurring on nanotextured surfaces, that give rise to local concentrations of incident far-field illumination. In this case, the far-field illumination comes from an x-ray source. Depending on the chemical composition and the geometry of a given nanotextured surface, these phenomena could include the lightning-rod effect (concentration of electric fields at the sharpest points on needlelike surface features), surface plasmon resonances, and grazing incidence geometric effects. In the far field, the observable effect of these phenomena is an increase in the intensity of the spectrum of interest - in this case, the x-ray fluorescence spectrum of chemical elements of interest that may be present within a surface layer at distances no more than a few nanometers from the surface.

  10. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy.

    Science.gov (United States)

    Miaja-Avila, L; O'Neil, G C; Uhlig, J; Cromer, C L; Dowell, M L; Jimenez, R; Hoover, A S; Silverman, K L; Ullom, J N

    2015-03-01

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼10(6) photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >10(7) laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  11. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    L. Miaja-Avila

    2015-03-01

    Full Text Available We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  12. Simultaneous X-ray fluorescence and scanning X-ray diffraction microscopy at the Australian Synchrotron XFM beamline

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Michael W. M.; Phillips, Nicholas W.; van Riessen, Grant A.; Abbey, Brian; Vine, David J.; Nashed, Youssef S. G.; Mudie, Stephen T.; Afshar, Nader; Kirkham, Robin; Chen, Bo; Balaur, Eugeniu; de Jonge, Martin D.

    2016-08-11

    Owing to its extreme sensitivity, quantitative mapping of elemental distributionsviaX-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

  13. Laser-based X-ray and electron source for X-ray fluorescence studies

    Science.gov (United States)

    Valle Brozas, F.; Crego, A.; Roso, L.; Peralta Conde, A.

    2016-08-01

    In this work, we present a modification to conventional X-rays fluorescence using electrons as excitation source and compare it with the traditional X-ray excitation for the study of pigments. For this purpose, we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However, electrons are stopped in the first layers, allowing a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

  14. Optimizing a time-resolved X-ray absorption experiment

    CERN Document Server

    Bressler, C; Chergui, M; Abela, R; Pattison, P

    2001-01-01

    Calculations are presented of the optimum conditions for performing a laser-pump X-ray probe time-resolved X-ray absorption experiment. The results concerning sensitivity and feasibility for implementing the method are illustrated for the case of the nascent I radical environment following I sup - photolysis in H sub 2 O.

  15. X-ray characterization by energy-resolved powder diffraction

    Directory of Open Access Journals (Sweden)

    G. Cheung

    2016-08-01

    Full Text Available A method for single-shot, nondestructive characterization of broadband x-ray beams, based on energy-resolved powder diffraction, is described. Monte-Carlo simulations are used to simulate data for x-ray beams in the keV range with parameters similar to those generated by betatron oscillations in a laser-driven plasma accelerator. The retrieved x-ray spectra are found to be in excellent agreement with those of the input beams for realistic numbers of incident photons. It is demonstrated that the angular divergence of the x rays can be deduced from the deviation of the detected photons from the Debye-Scherrer rings which would be produced by a parallel beam. It is shown that the angular divergence can be measured as a function of the photon energy, yielding the angularly resolved spectrum of the input x-ray beam.

  16. Review of X-ray Tomography and X-ray Fluorescence Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shear, Trevor A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-16

    This literature review will focus on both laboratory and synchrotron based X-ray tomography of materials and highlight the inner workings of these instruments. X-ray fluorescence spectroscopy will also be reviewed and applications of the tandem use of these techniques will be explored. The real world application of these techniques during the internship will also be discussed.

  17. A Monte Carlo study of x-ray fluorescence in x-ray detectors.

    Science.gov (United States)

    Boone, J M; Seibert, J A; Sabol, J M; Tecotzky, M

    1999-06-01

    Advances in digital x-ray detector systems have led to a renewed interest in the performance of x-ray phosphors and other detector materials. Indirect flat panel x-ray detector and charged coupled device (CCD) systems require a more technologically challenging geometry, whereby the x-ray beam is incident on the front side of the scintillator, and the light produced must diffuse to the back surface of the screen to reach the photoreceptor. Direct detector systems based on selenium have also enjoyed a growing interest, both commercially and academically. Monte Carlo simulation techniques were used to study the x-ray scattering (Rayleigh and Compton) and the more prevalent x-ray fluorescence properties of seven different x-ray detector materials, Gd2O2S, CsI, Se, BaFBr, YTaO4, CaWO4, and ThO2. The redistribution of x-ray energy, back towards the x-ray source, in a forward direction through the detector, and lateral reabsorption in the detector was computed under monoenergetic conditions (1 keV to 130 keV by 1 keV intervals) with five detector thicknesses, 30, 60, 90, 120, and 150 mg/cm2 (Se was studied from 30 to 1000 mg/cm2). The radial distribution (related to the point spread function) of reabsorbed x-ray energy was also determined. Representative results are as follows: At 55 keV, more (31.3%) of the incident x-ray energy escaped from a 90 mg/cm2Gd2O2S detector than was absorbed (27.9%). Approximately 1% of the total absorbed energy was reabsorbed greater than 0.5 mm from the primary interaction, for 90 mg/cm2 CsI exposed at 100 kVp. The ratio of reabsorbed secondary (fluorescence + scatter) radiation to the primary radiation absorbed in the detectors (90 mg/cm2) (S/P) was determined as 10%, 16%, 2%, 12%, 3%, 3%, and 0.3% for a 100 kVp tungsten anode x-ray spectrum, for the Gd2O2S, CsI, Se, BaFBr, YTaO4, CaWO4, and ThO2 detectors, respectively. The results indicate significant x-ray fluorescent escape and reabsorption in common x-ray detectors. These findings

  18. Multimode Surface Functional Group Determination: Combining Steady-State and Time-Resolved Fluorescence with X-ray Photoelectron Spectroscopy and Absorption Measurements for Absolute Quantification.

    Science.gov (United States)

    Fischer, Tobias; Dietrich, Paul M; Unger, Wolfgang E S; Rurack, Knut

    2016-01-19

    The quantitative determination of surface functional groups is approached in a straightforward laboratory-based method with high reliability. The application of a multimode BODIPY-type fluorescence, photometry, and X-ray photoelectron spectroscopy (XPS) label allows estimation of the labeling ratio, i.e., the ratio of functional groups carrying a label after reaction, from the elemental ratios of nitrogen and fluorine. The amount of label on the surface is quantified with UV/vis spectrophotometry based on the molar absorption coefficient as molecular property. The investigated surfaces with varying density are prepared by codeposition of 3-(aminopropyl)triethoxysilane (APTES) and cyanoethyltriethoxysilane (CETES) from vapor. These surfaces show high functional group densities that result in significant fluorescence quenching of surface-bound labels. Since alternative quantification of the label on the surface is available through XPS and photometry, a novel method to quantitatively account for fluorescence quenching based on fluorescence lifetime (τ) measurements is shown. Due to the complex distribution of τ on high-density surfaces, the stretched exponential (or Kohlrausch) function is required to determine representative mean lifetimes. The approach is extended to a commercial Rhodamine B isothiocyanate (RITC) label, clearly revealing the problems that arise from such charged labels used in conjunction with silane surfaces.

  19. The Mapping X-Ray Fluorescence Spectrometer (mapx)

    Science.gov (United States)

    Blake, D. F.; Sarrazin, P.; Bristow, T.; Downs, R. T.; Gailhanou, M.; Marchis, F.; Ming, D. W.; Morris, R. V.; Sole, V. A.; Thompson, K.; Walter, P.; Wilson, M.; Yen, A. S.; Webb, S.

    2016-12-01

    MapX will provide elemental imaging at ≤100 µm spatial resolution over 2.5 X 2.5 cm areas, yielding elemental chemistry at or below the scale length where many relict physical, chemical, and biological features can be imaged and interpreted in ancient rocks. MapX is a full-frame spectroscopic imager positioned on soil or regolith with touch sensors. During an analysis, an X-ray source (tube or radioisotope) bombards the sample surface with X-rays or α-particles / γ-rays, resulting in sample X-ray Fluorescence (XRF). Fluoresced X-rays pass through an X-ray lens (X-ray µ-Pore Optic, "MPO") that projects a spatially resolved image of the X-rays onto a CCD. The CCD is operated in single photon counting mode so that the positions and energies of individual photons are retained. In a single analysis, several thousand frames are stored and processed. A MapX experiment provides elemental maps having a spatial resolution of ≤100 µm and quantitative XRF spectra from Regions of Interest (ROI) 2 cm ≤ x ≤ 100 µm. ROI are compared with known rock and mineral compositions to extrapolate the data to rock types and putative mineralogies. The MapX geometry is being refined with ray-tracing simulations and with synchrotron experiments at SLAC. Source requirements are being determined through Monte Carlo modeling and experiment using XMIMSIM [1], GEANT4 [2] and PyMca [3] and a dedicated XRF test fixture. A flow-down of requirements for both tube and radioisotope sources is being developed from these experiments. In addition to Mars lander and rover missions, MapX could be used for landed science on other airless bodies (Phobos/Deimos, Comet nucleus, asteroids, the Earth's moon, and the icy satellites of the outer planets, including Europa. [1] Schoonjans, T. et al.(2012). Spectrachim. Acta Part B, 70, 10-23. [2] Agostinelli, S. et al. (2003). Nucl. Instr. and Methods in Phys. Research A, 506, 250-303. [3] V.A. Solé et al. (2007). Spectrochim. Acta Part B, 62, 63-68.

  20. Coded Aperture Imaging for Fluorescent X-rays-Biomedical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Haboub, Abdel; MacDowell, Alastair; Marchesini, Stefano; Parkinson, Dilworth

    2013-06-01

    Employing a coded aperture pattern in front of a charge couple device pixilated detector (CCD) allows for imaging of fluorescent x-rays (6-25KeV) being emitted from samples irradiated with x-rays. Coded apertures encode the angular direction of x-rays and allow for a large Numerical Aperture x- ray imaging system. The algorithm to develop the self-supported coded aperture pattern of the Non Two Holes Touching (NTHT) pattern was developed. The algorithms to reconstruct the x-ray image from the encoded pattern recorded were developed by means of modeling and confirmed by experiments. Samples were irradiated by monochromatic synchrotron x-ray radiation, and fluorescent x-rays from several different test metal samples were imaged through the newly developed coded aperture imaging system. By choice of the exciting energy the different metals were speciated.

  1. Theory of time-resolved inelastic x-ray diffraction

    DEFF Research Database (Denmark)

    Lorenz, Ulf; Møller, Klaus Braagaard; Henriksen, Niels Engholm

    2010-01-01

    Starting from a general theory of time-resolved x-ray scattering, we derive a convenient expression for the diffraction signal based on a careful analysis of the relevant inelastic scattering processes. We demonstrate that the resulting inelastic limit applies to a wider variety of experimental...... conditions than similar, previously derived formulas, and it directly allows the application of selection rules when interpreting diffraction signals. Furthermore, we present a simple extension to systems simultaneously illuminated by x rays and a laser beam....

  2. Laser-based X-ray and electron source for X-ray fluorescence studies

    CERN Document Server

    Brozas, F Valle; Roso, L; Conde, A Peralta

    2016-01-01

    In this work we present a modification to conventional X-rays fluorescence using electrons as excitation source, and compare it with the traditional X-ray excitation for the study of pigments. For this purpose we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However electrons are stopped in the first layers allowing therefore a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

  3. Energy-dispersive X-ray diffraction mapping on a benchtop X-ray fluorescence system

    OpenAIRE

    Lane, D W.; Nyombi, A.; Shackel, J.

    2014-01-01

    A method for energy-dispersive X-ray diffraction mapping is presented, using a conventional low-power benchtop X-ray fluorescence spectrometer, the Seiko Instruments SEA6000VX. Hyper spectral X-ray maps with a 10µm step size were collected from polished metal surfaces, sectioned Bi, Pb and steel shot gun pellets. Candidate diffraction lines were identified by eliminating those that matched a characteristic line for an element and those predicted for escape peaks, sum peaks, and Rayleigh and C...

  4. Milli X-Ray Fluorescence Spectrometer

    Data.gov (United States)

    Federal Laboratory Consortium — The Eagle III Micro XRF unit is similar to a traditional XRF unit, with the primary difference being that the X-rays are focused by a polycapillary optic into a spot...

  5. High-Definition X-Ray Fluorescence: Applications

    OpenAIRE

    Gibson, Walter M.; Chen, Z W; Li, Danhong

    2008-01-01

    Energy dispersive X-ray fluorescence (EDXRF) is a well-established and powerful tool for nondestructive elemental analysis of virtually any material. It is widely used for environmental, industrial, pharmaceutical, forensic, and scientific research applications to measure the concentration of elemental constituents or contaminants. The fluorescing atoms can be excited by energetic electrons, ions, or photons. A particular EDXRF method, monochromatic microbeam X-ray fluorescence (MμEDXRF), has...

  6. High Definition X-Ray Fluorescence: Principles and Techniques

    OpenAIRE

    Chen, Z W; Gibson, Walter M.; Huang, Huapeng

    2008-01-01

    Energy dispersive X-ray fluorescence (EDXRF) is a well-established and powerful tool for nondestructive elemental analysis of virtually any material. It is widely used for environmental, industrial, pharmaceutical, forensic, and scientific research applications to measure the concentration of elemental constituents or contaminants. The fluorescing atoms can be excited by energetic electrons, ions, or photons. A particular EDXRF method, monochromatic microfocus X-ray fluorescence (MμEDXRF), ha...

  7. Time Resolved X-Ray Scattering of molecules in Solution

    DEFF Research Database (Denmark)

    Brandt van Driel, Tim

    The dissertation describes the use of Time-Resolved X-ray Diffuse Scattering (TR-XDS) to study photo-induced structural changes in molecules in solution. The application of the technique is exemplified with experiments on two bimetallic molecules. The main focus is on the data-flow and process...... of bringing the data from measurement to analysis. Bridging the experimental design and challenges of the experiments from X-ray synchrotrons to the newly available X-ray Free Electron Laser sources (XFEL).LCLS in California is the first XFEL to come online and delivers intense 30fs X-ray pulses, orders...... of magnitude shorter than the 100ps X-ray pulses available from synchroton sources. This increase in time-resolution allows for the use of X-ray techniques in a completely new time-domain, where coherent photo-induced changes in structure can be studied on their intrinsic time-scale. Measurements on Rh2(dimen...

  8. Energy response calibration of photon-counting detectors using x-ray fluorescence: a feasibility study.

    Science.gov (United States)

    Cho, H-M; Ding, H; Ziemer, B P; Molloi, S

    2014-12-07

    Accurate energy calibration is critical for the application of energy-resolved photon-counting detectors in spectral imaging. The aim of this study is to investigate the feasibility of energy response calibration and characterization of a photon-counting detector using x-ray fluorescence. A comprehensive Monte Carlo simulation study was performed using Geant4 Application for Tomographic Emission (GATE) to investigate the optimal technique for x-ray fluorescence calibration. Simulations were conducted using a 100 kVp tungsten-anode spectra with 2.7 mm Al filter for a single pixel cadmium telluride (CdTe) detector with 3 × 3 mm(2) in detection area. The angular dependence of x-ray fluorescence and scatter background was investigated by varying the detection angle from 20° to 170° with respect to the beam direction. The effects of the detector material, shape, and size on the recorded x-ray fluorescence were investigated. The fluorescent material size effect was considered with and without the container for the fluorescent material. In order to provide validation for the simulation result, the angular dependence of x-ray fluorescence from five fluorescent materials was experimentally measured using a spectrometer. Finally, eleven of the fluorescent materials were used for energy calibration of a CZT-based photon-counting detector. The optimal detection angle was determined to be approximately at 120° with respect to the beam direction, which showed the highest fluorescence to scatter ratio (FSR) with a weak dependence on the fluorescent material size. The feasibility of x-ray fluorescence for energy calibration of photon-counting detectors in the diagnostic x-ray energy range was verified by successfully calibrating the energy response of a CZT-based photon-counting detector. The results of this study can be used as a guideline to implement the x-ray fluorescence calibration method for photon-counting detectors in a typical imaging laboratory.

  9. X-ray Fluorescent Fe Kalpha Lines from Stellar Photospheres

    CERN Document Server

    Drake, Jeremy J; Swartz, Douglas A

    2007-01-01

    X-ray spectra from stellar coronae are reprocessed by the underlying photosphere through scattering and photoionization events. While reprocessed X-ray spectra reaching a distant observer are at a flux level of only a few percent of that of the corona itself, characteristic lines formed by inner shell photoionization of some abundant elements can be significantly stronger. The emergent photospheric spectra are sensitive to the distance and location of the fluorescing radiation and can provide diagnostics of coronal geometry and abundance. Here we present Monte Carlo simulations of the photospheric Kalpha doublet arising from quasi-neutral Fe irradiated by a coronal X-ray source. Fluorescent line strengths have been computed as a function of the height of the radiation source, the temperature of the ionising X-ray spectrum, and the viewing angle. We also illustrate how the fluorescence efficiencies scale with the photospheric metallicity and the Fe abundance. Based on the results we make three comments: (1) fl...

  10. Characterization of small particles by micro X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Thomasin C. [X-ray Optical Systems, Inc., East Greenbush, NY 12180 (United States)]. E-mail: tmiller@xos.com; Langley DeWitt, Helen [Chemistry Division, Analytical Chemistry Science, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Havrilla, George J. [Chemistry Division, Analytical Chemistry Science, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2005-11-15

    Micro X-ray fluorescence was used to study both homogeneous and heterogeneous particle systems. Specifically, homogeneous glass microspheres and heterogeneous soil particle samples were prepared by both bulk and single particle sample preparation methods for evaluation by micro X-ray fluorescence. Single particle sample preparation methods allow for single particles from a collected sample to be isolated and individually presented to the micro X-ray fluorescence instrument for analysis. Various particle dispersion methods, including immobilization onto Tacky Dot{sup TM} slides, mounting onto double-sided sticky tape affixed to polypropylene film, or attachment to polypropylene film using 3M Artist's Adhesive, were used to separate the sample particles for single particle analysis. These methods were then compared and evaluated for their ability to disperse the particles into an array of single separated particles for optimal micro X-ray fluorescence characterization with minimal background contribution from the particle mounting surface. Bulk methods of particle sample preparation, which included pellet preparation and aerosol impaction, used a large quantity of collected single particles to make a single homogeneous specimen for presentation to the instrument for analysis. It was found that single particle elemental analysis by micro X-ray fluorescence can be performed if the particles are well separated (minimum separation distance = excitation source beam diameter) down to a particle mass of {approx} 0.04 ng and a mean particle diameter of {approx} 0.06 {mu}m. Homogeneous particulates can be adequately characterized by micro X-ray fluorescence using either bulk or single particle analysis methods, with no loss of analytical information. Heterogeneous samples are much harder to characterize, and both single particle as well as bulk analyses must be performed on the sample to insure full elemental characterization by micro X-ray fluorescence.

  11. Resonant soft X-ray fluorescence spectra of molecules

    Energy Technology Data Exchange (ETDEWEB)

    Nordgren, J.; Glans, P.; Gunnelin, K.; Guo, J.; Skytt, P.; Saathe, C.; Wassdahl, N. [Uppsala Univ. (Sweden). Dept. of Phys.

    1997-08-01

    A review is presented of some recent advancements in resonant soft X-ray fluorescence spectroscopy applied to molecules. The concept of inelastic scattering is discussed for molecules with an element of symmetry, which introduces degeneracy or near-degeneracy of core excited states. The potential of the symmetry selection rules associated with resonant X-ray fluorescence is illustrated in studies of electronic structure as well as molecular dynamics. The use of polarized photons for exciting X-ray emission is discussed, and examples are presented where anisotropy of X-ray emission provides more detailed information. A brief section discusses the experimental considerations relevant for the spectroscopic technique. (orig.) With 013 figs., 28 refs.

  12. X-ray fluorescence cross sections for K and L x rays of the elements

    Energy Technology Data Exchange (ETDEWEB)

    Krause, M.O.; Nestor, C.W. Jr.; Sparks, C.J. Jr.; Ricci, E.

    1978-06-01

    X-ray fluorescence cross sections are calculated for the major x rays of the K series 5 less than or equal to Z less than or equal to 101, and the three L series 12 less than or equal to Z less than or equal to 101 in the energy range 1 to 200 keV. This calculation uses Scofield's theoretical partical photoionization cross sections, Krause's evaluation of fluorescence and Coster-Kronig yields, and Scofield's theoretical radiative rates. Values are presented in table and graph format, and an estimate of their accuracy is made. The following x rays are considered: K..cap alpha../sub 1/, K..cap alpha../sub 1/,/sub 2/, K..beta../sub 1/, K..beta../sub 1/,/sub 3/, L..cap alpha../sub 1/, L..cap alpha../sub 1/,/sub 2/, L..beta../sub 1/, L..beta../sub 2/,/sub 15/, L..beta../sub 3/, Ll, L..gamma../sub 1/, L..gamma../sub 4/, and L/sub 1/ ..-->.. L/sub 2/,/sub 3/. For use in x-ray fluorescence analysis, K..cap alpha.. and L..cap alpha.. fluorescence cross sections are presented at specific energies: TiK identical with 4.55 keV, CrK identical with 5.46 keV, CoK identical with 7.00 keV, CuK identical with 8.13 keV, MoK..cap alpha.. identical with 17.44 keV, AgK identical with 22.5 keV, DyK identical with 47.0 keV, and /sup 241/Am identical with 59.54 keV. Supplementary material includes fluorescence and Coster--Kronig yields, fractional radiative rates, fractional fluorescence yields, total L-shell fluorescence cross sections, fluorescence and Coster-Kronig yields in condensed matter, effective fluorescence yields, average L-shell fluorescence yield, L-subshell photoionization cross section ratios, and conversion factors from barns per atom to square centimeters per gram.

  13. Remote X-Ray Diffraction and X-Ray Fluorescence Analysis on Planetary Surfaces

    Science.gov (United States)

    Blake, David F.; DeVincenzi, D. (Technical Monitor)

    1999-01-01

    The legacy of planetary X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) began in 1960 when W. Parish proposed an XRD instrument for deployment on the moon. The instrument was built and flight qualified, but the Lunar XRD program was cancelled shortly before the first human landing in 1969. XRF chemical data have been collected in situ by surface landers on Mars (Viking 1 & 2, Pathfinder) and Venus (Venera 13 & 14). These highly successful experiments provide critical constraints on our current understanding of surface processes and planetary evolution. However, the mineralogy, which is more critical to planetary surface science than simple chemical analysis, will remain unknown or will at best be imprecisely constrained until X-ray diffraction (XRD) data are collected. Recent progress in X-ray detector technology allows the consideration of simultaneous XRD (mineralogic analysis) and high-precision XRF (elemental analysis) in systems miniaturized to the point where they can be mounted on fixed landers or small robotic rovers. There is a variety of potential targets for XRD/XRF equipped landers within the solar system, the most compelling of which are the poles of the moon, the southern highlands of Mars and Europa.

  14. MSL Chemistry and Mineralogy X-Ray Diffraction X-Ray Fluorescence (CheMin) Instrument

    Science.gov (United States)

    Zimmerman, Wayne; Blake, Dave; Harris, William; Morookian, John Michael; Randall, Dave; Reder, Leonard J.; Sarrazin, Phillipe

    2013-01-01

    This paper provides an overview of the Mars Science Laboratory (MSL) Chemistry and Mineralogy Xray Diffraction (XRD), X-ray Fluorescence (XRF) (CheMin) Instrument, an element of the landed Curiosity rover payload, which landed on Mars in August of 2012. The scientific goal of the MSL mission is to explore and quantitatively assess regions in Gale Crater as a potential habitat for life - past or present. The CheMin instrument will receive Martian rock and soil samples from the MSL Sample Acquisition/Sample Processing and Handling (SA/SPaH) system, and process it utilizing X-Ray spectroscopy methods to determine mineral composition. The Chemin instrument will analyze Martian soil and rocks to enable scientists to investigate geophysical processes occurring on Mars. The CheMin science objectives and proposed surface operations are described along with the CheMin hardware with an emphasis on the system engineering challenges associated with developing such a complex instrument.

  15. MSL Chemistry and Mineralogy X-Ray Diffraction X-Ray Fluorescence (CheMin) Instrument

    Science.gov (United States)

    Zimmerman, Wayne; Blake, Dave; Harris, William; Morookian, John Michael; Randall, Dave; Reder, Leonard J.; Sarrazin, Phillipe

    2013-01-01

    This paper provides an overview of the Mars Science Laboratory (MSL) Chemistry and Mineralogy Xray Diffraction (XRD), X-ray Fluorescence (XRF) (CheMin) Instrument, an element of the landed Curiosity rover payload, which landed on Mars in August of 2012. The scientific goal of the MSL mission is to explore and quantitatively assess regions in Gale Crater as a potential habitat for life - past or present. The CheMin instrument will receive Martian rock and soil samples from the MSL Sample Acquisition/Sample Processing and Handling (SA/SPaH) system, and process it utilizing X-Ray spectroscopy methods to determine mineral composition. The Chemin instrument will analyze Martian soil and rocks to enable scientists to investigate geophysical processes occurring on Mars. The CheMin science objectives and proposed surface operations are described along with the CheMin hardware with an emphasis on the system engineering challenges associated with developing such a complex instrument.

  16. HIgh Rate X-ray Fluorescence Detector

    Energy Technology Data Exchange (ETDEWEB)

    Grudberg, Peter Matthew [XIA LLC

    2013-04-30

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with

  17. Instrument and method for X-ray diffraction, fluorescence, and crystal texture analysis without sample preparation

    Science.gov (United States)

    Gendreau, Keith (Inventor); Martins, Jose Vanderlei (Inventor); Arzoumanian, Zaven (Inventor)

    2010-01-01

    An X-ray diffraction and X-ray fluorescence instrument for analyzing samples having no sample preparation includes a X-ray source configured to output a collimated X-ray beam comprising a continuum spectrum of X-rays to a predetermined coordinate and a photon-counting X-ray imaging spectrometer disposed to receive X-rays output from an unprepared sample disposed at the predetermined coordinate upon exposure of the unprepared sample to the collimated X-ray beam. The X-ray source and the photon-counting X-ray imaging spectrometer are arranged in a reflection geometry relative to the predetermined coordinate.

  18. Measuring and interpreting X-ray fluorescence from planetary surfaces.

    Science.gov (United States)

    Owens, Alan; Beckhoff, Burkhard; Fraser, George; Kolbe, Michael; Krumrey, Michael; Mantero, Alfonso; Mantler, Michael; Peacock, Anthony; Pia, Maria-Grazia; Pullan, Derek; Schneider, Uwe G; Ulm, Gerhard

    2008-11-15

    As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase.

  19. X-ray fluorescence microscopy of olfactory receptor neurons

    Energy Technology Data Exchange (ETDEWEB)

    Ducic, T; Herbst, J; Novakova, E; Salditt, T [Institute for X-ray Physics, Georg-August-University, Friedrich-Hund-Pl. 1, 37077 Goettingen (Germany); Breunig, E; Schild, D [Department of Molecular Neurophysiology, Georg-August University Goettingen (Germany); Susini, J; Tucoulu, R, E-mail: tducic@gwdg.d [European Synchrotron Radiation Facility ESRF, 6 rue Jules Horowitz, 38043 Grenoble (France)

    2009-09-01

    We report a x-ray fluorescence microscopy study of cells and tissues from the olfactory system of Xenopus laevis. In this experiment we focus on sample preparation and experimental issues, and present first results of fluorescence maps of the elemental distribution of Cl, K, Ca, P, S and Na both in individual isolated neural cells and in cross-sections of the same tissue.

  20. Submicron hard X-ray fluorescence imaging of synthetic elements

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Mark P., E-mail: mjensen@anl.gov [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Aryal, Baikuntha P. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Department of Chemistry, University of Chicago, Chicago, IL 60637 (United States); Gorman-Lewis, Drew [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Paunesku, Tatjana [Department of Radiation Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States); Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States); Lai, Barry; Vogt, Stefan [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Woloschak, Gayle E. [Department of Radiation Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States); Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States)

    2012-04-13

    Highlights: Black-Right-Pointing-Pointer Actinide elements are mapped with L-edge X-rays and better than 400 nm resolution. Black-Right-Pointing-Pointer A typical detection limit was 2.9 Multiplication-Sign 10{sup -20} moles Pu {mu}m{sup -2}. Black-Right-Pointing-Pointer XANES measurements provide chemical information in 0.1 {mu}m{sup 2} spots. Black-Right-Pointing-Pointer Selection of materials for encapsulation is important for avoiding interferences. - Abstract: Synchrotron-based X-ray fluorescence microscopy (XFM) using hard X-rays focused into sub-micron spots is a powerful technique for elemental quantification and mapping, as well as microspectroscopic measurements such as {mu}-XANES (X-ray absorption near edge structure). We have used XFM to image and simultaneously quantify the transuranic element plutonium at the L{sub 3} or L{sub 2}-edge as well as Th and lighter biologically essential elements in individual rat pheochromocytoma (PC12) cells after exposure to the long-lived plutonium isotope {sup 242}Pu. Elemental maps demonstrate that plutonium localizes principally in the cytoplasm of the cells and avoids the cell nucleus, which is marked by the highest concentrations of phosphorus and zinc, under the conditions of our experiments. The minimum detection limit under typical acquisition conditions with an incident X-ray energy of 18 keV for an average 202 {mu}m{sup 2} cell is 1.4 fg Pu or 2.9 Multiplication-Sign 10{sup -20} moles Pu {mu}m{sup -2}, which is similar to the detection limit of K-edge XFM of transition metals at 10 keV. Copper electron microscopy grids were used to avoid interference from gold X-ray emissions, but traces of strontium present in naturally occurring calcium can still interfere with plutonium detection using its L{sub {alpha}} X-ray emission.

  1. Portable energy dispersive X-ray fluorescence and X-ray diffraction and radiography system for archaeometry

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza Cuevas, Ariadna, E-mail: ariadna@mail.or [Archaeometry Laboratory, Colegio Universitario San Geronimo de La Habana, Obispo, entre San Ignacio y Mercaderes, Habana Vieja, cp 10 100, Havana (Cuba); Perez Gravie, Homero, E-mail: homero.perezgravie@mail.co [Archaeometry Laboratory, Colegio Universitario San Geronimo de La Habana, Obispo, entre San Ignacio y Mercaderes, Habana Vieja, cp 10 100, Havana (Cuba)

    2011-03-21

    Starting on a laboratory developed portable X-ray fluorescence (PXRF) spectrometer; three different analytical results can be performed: analysis of chemical elements, analysis of major chemical crystalline phase and structural analysis, which represents a contribution to a new, low cost development of portable X-ray analyzer; since these results are respectively obtained with independent equipments for X-ray fluorescence, X-ray diffraction and radiography. Detection limits of PXRF were characterized using standard reference materials for ceramics, glass, bronze and bones, which are the main materials requiring quantitative analysis in art and archeological objects. A setup for simultaneous energy dispersive X-ray fluorescence and diffraction (ED (XRF-XRD)) in the reflection mode has been tested for in situ and non-destructive analysis according to the requirements of art objects inspection. The system uses a single low power X-ray tube and an X-ray energy dispersive detector to measure X-ray diffraction spectrum at a fixed angle. Application to the identification of jadeite-jade mineral in archeological objects by XRD is presented. A local high resolution radiography image obtained with the same low power X-ray tube allows for studies in painting and archeological bones.

  2. X-ray fluorescence measurements of dissolved gas and cavitation

    Science.gov (United States)

    Duke, Daniel J.; Kastengren, Alan L.; Swantek, Andrew B.; Matusik, Katarzyna E.; Powell, Christopher F.

    2016-10-01

    The dynamics of dissolved gas and cavitation are strongly coupled, yet these phenomena are difficult to measure in-situ. Both create voids in the fluid that can be difficult to distinguish. We present an application of X-ray fluorescence in which liquid density and total noncondensible gas concentration (both dissolved and nucleated) are simultaneously measured. The liquid phase is doped with 400 ppm of a bromine tracer, and dissolved air is removed and substituted with krypton. Fluorescent emission at X-ray wavelengths is simultaneously excited from the Br and Kr with a focused monochromatic X-ray beam from a synchrotron source. We measure the flow in a cavitating nozzle 0.5 mm in diameter. From Br fluorescence, total displacement of the liquid is measured. From Kr fluorescence, the mass fraction of both dissolved and nucleated gas is measured. Volumetric displacement of liquid due to both cavitation and gas precipitation can be separated through estimation of the local equilibrium dissolved mass fraction. The uncertainty in the line of sight projected densities of the liquid and gas phases is 4-6 %. The high fluorescence yields and energies of Br and Kr allow small mass fractions of gas to be measured, down to 10-5, with an uncertainty of 8 %. These quantitative measurements complement existing optical diagnostic techniques and provide new insight into the diffusion of gas into cavitation bubbles, which can increase their internal density, pressure and lifetimes by orders of magnitude.

  3. A new X-ray pinhole camera for energy dispersive X-ray fluorescence imaging with high-energy and high-spatial resolution

    Energy Technology Data Exchange (ETDEWEB)

    Romano, F.P., E-mail: romanop@lns.infn.it [IBAM, CNR, Via Biblioteca 4, 95124 Catania (Italy); INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy); Altana, C. [INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia 64, 95123 Catania (Italy); Cosentino, L.; Celona, L.; Gammino, S.; Mascali, D. [INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy); Pappalardo, L. [IBAM, CNR, Via Biblioteca 4, 95124 Catania (Italy); INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy); Rizzo, F. [INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia 64, 95123 Catania (Italy)

    2013-08-01

    A new X-ray pinhole camera for the Energy Dispersive X-ray Fluorescence (ED-XRF) imaging of materials with high-energy and high-spatial resolution, was designed and developed. It consists of a back-illuminated and deep depleted CCD detector (composed of 1024 × 1024 pixels with a lateral size of 13 μm) coupled to a 70 μm laser-drilled pinhole-collimator, positioned between the sample under analysis and the CCD. The X-ray pinhole camera works in a coaxial geometry allowing a wide range of magnification values. The characteristic X-ray fluorescence is induced on the samples by irradiation with an external X-ray tube working at a maximum power of 100 W (50 kV and 2 mA operating conditions). The spectroscopic capabilities of the X-ray pinhole camera were accurately investigated. Energy response and energy calibration of the CCD detector were determined by irradiating pure target-materials emitting characteristic X-rays in the energy working-domain of the system (between 3 keV and 30 keV). Measurements were performed by using a multi-frame acquisition in single-photon counting. The characteristic X-ray spectra were obtained by an automated processing of the acquired images. The energy resolution measured at the Fe–Kα line is 157 eV. The use of the X-ray pinhole camera for the 2D resolved elemental analysis was investigated by using reference-patterns of different materials and geometries. The possibility of the elemental mapping of samples up to an area of 3 × 3 cm{sup 2} was demonstrated. Finally, the spatial resolution of the pinhole camera was measured by analyzing the profile function of a sharp-edge. The spatial resolution determined at the magnification values of 3.2 × and 0.8 × (used as testing values) is about 90 μm and 190 μm respectively. - Highlights: • We developed an X-ray pinhole camera for the 2D X-ray fluorescence imaging. • X-ray spectra are obtained by a multi-frame acquisition in single photon mode. • The energy resolution in the X-ray

  4. Use of a Superconducting Tunnel Junction for X-Ray Fluorescence Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hiller, L

    2001-03-06

    A superconducting tunnel junction (STJ) in combination with a superconducting absorber of radiation may function as a highly resolving x-ray spectrometer. Electronic excitations, or quasiparticles, are created when a superconductor absorbs an x ray and are detected as an excess tunnel current through the junction. The number of quasiparticles created and the magnitude of the excess current is proportional to the energy of the absorbed x ray. This is similar to existing semiconductor-based spectrometers that measure electron-hole pairs, but with 1000 times more excitations. The energy measurement therefore can be up to 30 times more precise with a superconducting detector than with a semiconductor detector. This work describes the development and testing of an STJ spectrometer design for x-ray fluorescence applications. First, the basic principles of the STJ spectrometer are explained. This is followed by detailed simulations of the variance in the number of quasiparticles produced by absorption of an x ray. This variance is inherent in the detector and establishes an upper limit on the resolving power of the spectrometer. These simulations include effects due to the materials used in the spectrometer and to the multilayer structure of the device. Next, the spectrometer is characterized as functions of operating temperature, incident x-ray energy, and count rate. Many of these tests were performed with the spectrometer attached to a synchrotron radiation port. Finally, example x-ray fluorescence spectra of materials exposed to synchrotron radiation are presented. These materials are of interest to semiconductor processing and structural biology, two fields that will benefit immediately from the improved resolving power of the STJ spectrometer.

  5. Toward picosecond time-resolved X-ray absorption studies of interfacial photochemistry

    Science.gov (United States)

    Gessner, Oliver; Mahl, Johannes; Neppl, Stefan

    2016-05-01

    We report on the progress toward developing a novel picosecond time-resolved transient X-ray absorption spectroscopy (TRXAS) capability for time-domain studies of interfacial photochemistry. The technique is based on the combination of a high repetition rate picosecond laser system with a time-resolved X-ray fluorescent yield setup that may be used for the study of radiation sensitive materials and X-ray spectroscopy compatible photoelectrochemical (PEC) cells. The mobile system is currently deployed at the Advanced Light Source (ALS) and may be used in all operating modes (two-bunch and multi-bunch) of the synchrotron. The use of a time-stamping technique enables the simultaneous recording of TRXAS spectra with delays between the exciting laser pulses and the probing X-ray pulses spanning picosecond to nanosecond temporal scales. First results are discussed that demonstrate the viability of the method to study photoinduced dynamics in transition metal-oxide semiconductor (SC) samples under high vacuum conditions and at SC-liquid electrolyte interfaces during photoelectrochemical water splitting. Opportunities and challenges are outlined to capture crucial short-lived intermediates of photochemical processes with the technique. This work was supported by the Department of Energy Office of Science Early Career Research Program.

  6. Development and applications of grazing exit micro X-ray fluorescence instrument using a polycapillary X-ray lens*1

    Science.gov (United States)

    Emoto, T.; Sato, Y.; Konishi, Y.; Ding, X.; Tsuji, K.

    2004-08-01

    A polycapillary X-ray lens is an effective optics to obtain a μm-size X-ray beam for micro-X-ray fluorescence spectrometry (μ-XRF). We developed a μ-XRF instrument using a polycapillary X-ray lens, which also enabled us to perform Grazing Exit μ-XRF (GE-μ-XRF). The evaluated diameter of the primary X-ray beam was 48 μm at the focal distance of the X-ray lens. Use of this instrument enabled two-dimensional mapping of the elemental distributions during growth of the plant "Quinoa". The results of the mapping revealed elemental transition during growth. In addition, a small region of thin film was analyzed by GE-μ-XRF. We expect that GE-μ-XRF will become an effective method of estimating the film thickness of a small region.

  7. Development and applications of grazing exit micro X-ray fluorescence instrument using a polycapillary X-ray lens

    Energy Technology Data Exchange (ETDEWEB)

    Emoto, T.; Sato, Y.; Konishi, Y.; Ding, X.; Tsuji, K. E-mail: tsuji@a-chem.eng.osaka-cu.ac.jp

    2004-08-31

    A polycapillary X-ray lens is an effective optics to obtain a {mu}m-size X-ray beam for micro-X-ray fluorescence spectrometry ({mu}-XRF). We developed a {mu}-XRF instrument using a polycapillary X-ray lens, which also enabled us to perform Grazing Exit {mu}-XRF (GE-{mu}-XRF). The evaluated diameter of the primary X-ray beam was 48 {mu}m at the focal distance of the X-ray lens. Use of this instrument enabled two-dimensional mapping of the elemental distributions during growth of the plant 'Quinoa'. The results of the mapping revealed elemental transition during growth. In addition, a small region of thin film was analyzed by GE-{mu}-XRF. We expect that GE-{mu}-XRF will become an effective method of estimating the film thickness of a small region.

  8. Proton-induced x-ray fluorescence CT imaging.

    Science.gov (United States)

    Bazalova-Carter, Magdalena; Ahmad, Moiz; Matsuura, Taeko; Takao, Seishin; Matsuo, Yuto; Fahrig, Rebecca; Shirato, Hiroki; Umegaki, Kikuo; Xing, Lei

    2015-02-01

    To demonstrate the feasibility of proton-induced x-ray fluorescence CT (pXFCT) imaging of gold in a small animal sized object by means of experiments and Monte Carlo (MC) simulations. First, proton-induced gold x-ray fluorescence (pXRF) was measured as a function of gold concentration. Vials of 2.2 cm in diameter filled with 0%-5% Au solutions were irradiated with a 220 MeV proton beam and x-ray fluorescence induced by the interaction of protons, and Au was detected with a 3 × 3 mm(2) CdTe detector placed at 90° with respect to the incident proton beam at a distance of 45 cm from the vials. Second, a 7-cm diameter water phantom containing three 2.2-diameter vials with 3%-5% Au solutions was imaged with a 7-mm FWHM 220 MeV proton beam in a first generation CT scanning geometry. X-rays scattered perpendicular to the incident proton beam were acquired with the CdTe detector placed at 45 cm from the phantom positioned on a translation/rotation stage. Twenty one translational steps spaced by 3 mm at each of 36 projection angles spaced by 10° were acquired, and pXFCT images of the phantom were reconstructed with filtered back projection. A simplified geometry of the experimental data acquisition setup was modeled with the MC TOPAS code, and simulation results were compared to the experimental data. A linear relationship between gold pXRF and gold concentration was observed in both experimental and MC simulation data (R(2) > 0.99). All Au vials were apparent in the experimental and simulated pXFCT images. Specifically, the 3% Au vial was detectable in the experimental [contrast-to-noise ratio (CNR) = 5.8] and simulated (CNR = 11.5) pXFCT image. Due to fluorescence x-ray attenuation in the higher concentration vials, the 4% and 5% Au contrast were underestimated by 10% and 15%, respectively, in both the experimental and simulated pXFCT images. Proton-induced x-ray fluorescence CT imaging of 3%-5% gold solutions in a small animal sized water phantom has been demonstrated

  9. Proton-induced x-ray fluorescence CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bazalova-Carter, Magdalena, E-mail: bazalova@stanford.edu; Xing, Lei [Department of Radiation Oncology, Stanford University, Stanford, California 94305-5847 and Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo 060-8648 (Japan); Ahmad, Moiz [Department of Radiation Oncology, Stanford University, Stanford, California 94305-5847 (United States); Matsuura, Taeko; Takao, Seishin; Shirato, Hiroki; Umegaki, Kikuo [Department of Medical Physics, Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo 060-8648, Japan and Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo 060-8648 (Japan); Matsuo, Yuto [Department of Medical Physics, Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo 060-8648 (Japan); Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2015-02-15

    Purpose: To demonstrate the feasibility of proton-induced x-ray fluorescence CT (pXFCT) imaging of gold in a small animal sized object by means of experiments and Monte Carlo (MC) simulations. Methods: First, proton-induced gold x-ray fluorescence (pXRF) was measured as a function of gold concentration. Vials of 2.2 cm in diameter filled with 0%–5% Au solutions were irradiated with a 220 MeV proton beam and x-ray fluorescence induced by the interaction of protons, and Au was detected with a 3 × 3 mm{sup 2} CdTe detector placed at 90° with respect to the incident proton beam at a distance of 45 cm from the vials. Second, a 7-cm diameter water phantom containing three 2.2-diameter vials with 3%–5% Au solutions was imaged with a 7-mm FWHM 220 MeV proton beam in a first generation CT scanning geometry. X-rays scattered perpendicular to the incident proton beam were acquired with the CdTe detector placed at 45 cm from the phantom positioned on a translation/rotation stage. Twenty one translational steps spaced by 3 mm at each of 36 projection angles spaced by 10° were acquired, and pXFCT images of the phantom were reconstructed with filtered back projection. A simplified geometry of the experimental data acquisition setup was modeled with the MC TOPAS code, and simulation results were compared to the experimental data. Results: A linear relationship between gold pXRF and gold concentration was observed in both experimental and MC simulation data (R{sup 2} > 0.99). All Au vials were apparent in the experimental and simulated pXFCT images. Specifically, the 3% Au vial was detectable in the experimental [contrast-to-noise ratio (CNR) = 5.8] and simulated (CNR = 11.5) pXFCT image. Due to fluorescence x-ray attenuation in the higher concentration vials, the 4% and 5% Au contrast were underestimated by 10% and 15%, respectively, in both the experimental and simulated pXFCT images. Conclusions: Proton-induced x-ray fluorescence CT imaging of 3%–5% gold solutions in a

  10. Elemental analysis using a handheld X-Ray fluorescence spectrometer

    Science.gov (United States)

    Groover, Krishangi D.; Izbicki, John

    2016-06-24

    The U.S. Geological Survey is collecting geologic samples from local stream channels, aquifer materials, and rock outcrops for studies of trace elements in the Mojave Desert, southern California. These samples are collected because geologic materials can release a variety of elements to the environment when exposed to water. The samples are to be analyzed with a handheld X-ray fluorescence (XRF) spectrometer to determine the concentrations of up to 27 elements, including chromium.

  11. Identifications studies of Lauha Bhasma by X-ray diffraction and X-ray fluorescence

    Science.gov (United States)

    Bhargava, S. C.; Reddy, K. R. C; Sastry, G. V. S

    2012-01-01

    Procedures for preparation of Lauha Bhasma are described in ancient texts of Ayurveda. These procedures also begin with different source material for iron such as Teekshna Lauha and Kanta Lauha etc. In the present study, we have selected different source materials viz. magnetite iron ore for Kanta Lauha and pure (Armco grade) iron turnings for Teekshna Lauha. The standard procedures of preparation of Lauha Bhasma are carried out in identical conditions for these two raw materials. The final product from the Puta are characterized by using X-ray diffraction and X-ray fluorescence spectroscopy to understanding the crystallographic form or forms of iron oxides and their composition at the end of each Puta. The iron content at the end of repeated Putas (18 for Kanta Lauha and 20 for Teekshna Lauha) have shown a decrease in case of Teekshna Lauha since the starting material is pure iron while it showed only marginal decreases in the case of Kanta Lauha because the Fe3O4 of magnetite is undergoing oxidation to Fe2O3. The trace elements remain within the Bhasma in the form of various oxides of Si, Al, Ca, etc. PMID:23049200

  12. Identifications studies of Lauha Bhasma by X-ray diffraction and X-ray fluorescence.

    Science.gov (United States)

    Bhargava, S C; Reddy, K R C; Sastry, G V S

    2012-01-01

    Procedures for preparation of Lauha Bhasma are described in ancient texts of Ayurveda. These procedures also begin with different source material for iron such as Teekshna Lauha and Kanta Lauha etc. In the present study, we have selected different source materials viz. magnetite iron ore for Kanta Lauha and pure (Armco grade) iron turnings for Teekshna Lauha. The standard procedures of preparation of Lauha Bhasma are carried out in identical conditions for these two raw materials. The final product from the Puta are characterized by using X-ray diffraction and X-ray fluorescence spectroscopy to understanding the crystallographic form or forms of iron oxides and their composition at the end of each Puta. The iron content at the end of repeated Putas (18 for Kanta Lauha and 20 for Teekshna Lauha) have shown a decrease in case of Teekshna Lauha since the starting material is pure iron while it showed only marginal decreases in the case of Kanta Lauha because the Fe(3)O(4) of magnetite is undergoing oxidation to Fe(2)O(3). The trace elements remain within the Bhasma in the form of various oxides of Si, Al, Ca, etc.

  13. Time-resolved X-ray PIV technique for diagnosing opaque biofluid flow with insufficient X-ray fluxes.

    Science.gov (United States)

    Jung, Sung Yong; Park, Han Wook; Kim, Bo Heum; Lee, Sang Joon

    2013-05-01

    X-ray imaging is used to visualize the biofluid flow phenomena in a nondestructive manner. A technique currently used for quantitative visualization is X-ray particle image velocimetry (PIV). Although this technique provides a high spatial resolution (less than 10 µm), significant hemodynamic parameters are difficult to obtain under actual physiological conditions because of the limited temporal resolution of the technique, which in turn is due to the relatively long exposure time (~10 ms) involved in X-ray imaging. This study combines an image intensifier with a high-speed camera to reduce exposure time, thereby improving temporal resolution. The image intensifier amplifies light flux by emitting secondary electrons in the micro-channel plate. The increased incident light flux greatly reduces the exposure time (below 200 µs). The proposed X-ray PIV system was applied to high-speed blood flows in a tube, and the velocity field information was successfully obtained. The time-resolved X-ray PIV system can be employed to investigate blood flows at beamlines with insufficient X-ray fluxes under specific physiological conditions. This method facilitates understanding of the basic hemodynamic characteristics and pathological mechanism of cardiovascular diseases.

  14. Trends in environmental science using microscopic X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Fittschen, Ursula Elisabeth Adriane, E-mail: ursula.fittschen@chemie.uni-hamburg.de [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Falkenberg, Gerald [Deutsches Elektronen-Synchrotron, Notkestr. 85, 22603 Hamburg (Germany)

    2011-08-15

    Microscopic X-ray fluorescence (micro-XRF) is a versatile tool in environmental analysis. We review work done in this field from 2008 to 2010 and highlight new aspects. Overall, there is a strong trend to combine fluorescence data with other data like diffraction or absorption spectroscopy. Also, the use of laboratory based instrumentation has become wide spread as more commercial instruments are available. At laboratories and synchrotron sites the trend towards higher spatial resolution is still persistent hitting sub micrometer values in case of synchrotron set ups.

  15. Influence of angle's ranges for recording an X-ray fluorescence hologram on reconstructed atomic images

    Institute of Scientific and Technical Information of China (English)

    XIE Hong-Lan; CHEN Jian-Wen; GAO Hong-Yi; ZHU Hua-Feng; LI Ru-Xin; XU Zhi-Zhan

    2004-01-01

    X-ray fluorescence holography (XFH) is a novel method for three-dimensional (3D) imaging of atomic structure. Theoretically, in an XFH experiment, one has to measure the fluorescence energy on a spherical surface to get well-resolved 3D images of atoms. But in practice, the experimental system arrangement does not allow the measurement of the fluorescent intensity oscillations in the full sphere. The holographic information losses because of the limited sampling range (less than 4π) will directly result in defective reconstructed atomic images. In this work, the atomic image of a Fe single crystal (001) was reconstructed by numerically simulating X-ray fluorescence holograms of the crystal at different recording angle's ranges and step lengths. Influences of the ranges of azimuth angles and polar angles and the step length of polar angles on the reconstructed atomic images were discussed.

  16. Laboratory Setup for Scanning-Free Grazing Emission X-ray Fluorescence.

    Science.gov (United States)

    Baumann, J; Herzog, C; Spanier, M; Grötzsch, D; Lühl, L; Witte, K; Jonas, A; Günther, S; Förste, F; Hartmann, R; Huth, M; Kalok, D; Steigenhöfer, D; Krämer, M; Holz, T; Dietsch, R; Strüder, L; Kanngießer, B; Mantouvalou, I

    2017-02-07

    Grazing incidence and grazing emission X-ray fluorescence spectroscopy (GI/GE-XRF) are techniques that enable nondestructive, quantitative analysis of elemental depth profiles with a resolution in the nanometer regime. A laboratory setup for soft X-ray GEXRF measurements is presented. Reasonable measurement times could be achieved by combining a highly brilliant laser produced plasma (LPP) source with a scanning-free GEXRF setup, providing a large solid angle of detection. The detector, a pnCCD, was operated in a single photon counting mode in order to utilize its energy dispersive properties. GEXRF profiles of the Ni-Lα,β line of a nickel-carbon multilayer sample, which displays a lateral (bi)layer thickness gradient, were recorded at several positions. Simulations of theoretical profiles predicted a prominent intensity minimum at grazing emission angles between 5° and 12°, depending strongly on the bilayer thickness of the sample. This information was used to retrieve the bilayer thickness gradient. The results are in good agreement with values obtained by X-ray reflectometry, conventional X-ray fluorescence and transmission electron microscopy measurements and serve as proof-of-principle for the realized GEXRF setup. The presented work demonstrates the potential of nanometer resolved elemental depth profiling in the soft X-ray range with a laboratory source, opening, for example, the possibility of in-line or even in situ process control in semiconductor industry.

  17. Fluorescence versus X-ray cholangiography during laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Lehrskov, Lars Lang; Larsen, Søren S; Kristensen, Billy B

    2016-01-01

    ). The primary outcome is visualisation of the junction between the cystic duct, the common hepatic duct and the common bile duct. CONCLUSION: The present study may show that fluorescent cholangiography is as valid for visualisation of important structures of the extrahepatic biliary tract as conventional X......INTRODUCTION: Intraoperative fluorescent cholangiography is a novel non-invasive imaging technique to visualise the extrahepatic biliary tract during laparoscopic cholecystectomy. It has been proven feasible, fast and cost effective. Never-theless, there is only sparse data on the capacity...... of fluorescent cholangiography to visualise the biliary anatomy. METHODS: Based on a non-inferiority design, patients with complicated gallstone disease are randomised to either -intraoperative conventional X-ray cholangiography (reference group, n = 60) or intraoperative fluorescent cholangiography (n = 60...

  18. Fluorescence versus X-ray cholangiography during laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Lehrskov, Lars Lang; Larsen, Søren Schytt; Kristensen, Billy Bjarne

    2016-01-01

    INTRODUCTION: Intraoperative fluorescent cholangiography is a novel non-invasive imaging technique to visualise the extrahepatic biliary tract during laparoscopic cholecystectomy. It has been proven feasible, fast and cost effective. Never-theless, there is only sparse data on the capacity...... of fluorescent cholangiography to visualise the biliary anatomy. METHODS: Based on a non-inferiority design, patients with complicated gallstone disease are randomised to either -intraoperative conventional X-ray cholangiography (reference group, n = 60) or intraoperative fluorescent cholangiography (n = 60......). The primary outcome is visualisation of the junction between the cystic duct, the common hepatic duct and the common bile duct. CONCLUSION: The present study may show that fluorescent cholangiography is as valid for visualisation of important structures of the extrahepatic biliary tract as conventional X...

  19. X-ray Peltier cooled detectors for X-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Loupilov, A. E-mail: bsi@bsi.lv; Sokolov, A.; Gostilo, V

    2001-06-01

    The recent results on development of X-ray Si(Li), Si-planar and CdTe p-i-n detectors cooled by Peltier coolers for fabrication of laboratory and portable XRF analysers for different applications are discussed. Low detection limits of XRF analysers are provided by increasing of detectors sensitive surface; improvement of their spectrometrical characteristics; decreasing of front-end-electronics noise level; Peltier coolers and vacuum chambers cooling modes optimization. Solution of all mentioned tasks allowed to develop Peltier cooled detectors with the following performances: (1.) Si(Li) detectors: S=20 mm{sup 2}, thickness=3.5 mm, 175 eV (5.9 keV), 430 eV (59.6 keV); S=100 mm{sup 2}; thickness=4.5 mm, 270 eV (5.9 keV), 485 eV (59.6 keV). (2.) Si-planar detector: S=10 mm{sup 2}, thickness=0.4 mm, 230 eV (5.9 keV), 460 eV (59.6 keV). (3.) CdTe p-i-n detectors: S=16 mm{sup 2}, thickness=0.5 mm, 350 eV (5.9 keV), 585 eV (59.6 keV). S=16 mm{sup 2}, thickness=1.2 mm, 310 eV (5.9 keV), 600 eV (59.6 keV). Advantages and disadvantages of all types of detectors for X-ray fluorescence analysis are compared. Spectra are presented. Application of different XRF analysers based on developed detectors in medicine, environmental science, industry, cryminalistics and history of art are demonstrated.

  20. Resolving colocalization of bacteria and metal(loid)s on plant root surfaces by combining fluorescence in situ hybridization (FISH) with multiple-energy micro-focused X-ray fluorescence (ME μXRF).

    Science.gov (United States)

    Honeker, Linnea K; Root, Robert A; Chorover, Jon; Maier, Raina M

    2016-12-01

    Metal(loid)-contamination of the environment due to anthropogenic activities is a global problem. Understanding the fate of contaminants requires elucidation of biotic and abiotic factors that influence metal(loid) speciation from molecular to field scales. Improved methods are needed to assess micro-scale processes, such as those occurring at biogeochemical interfaces between plant tissues, microbial cells, and metal(loid)s. Here we present an advanced method that combines fluorescence in situ hybridization (FISH) with synchrotron-based multiple-energy micro-focused X-ray fluorescence microprobe imaging (ME μXRF) to examine colocalization of bacteria and metal(loid)s on root surfaces of plants used to phytostabilize metalliferous mine tailings. Bacteria were visualized on a small root section using SytoBC nucleic acid stain and FISH probes targeting the domain Bacteria and a specific group (Alphaproteobacteria, Gammaproteobacteria, or Actinobacteria). The same root region was then analyzed for elemental distribution and metal(loid) speciation of As and Fe using ME μXRF. The FISH and ME μXRF images were aligned using ImageJ software to correlate microbiological and geochemical results. Results from quantitative analysis of colocalization show a significantly higher fraction of As colocalized with Fe-oxide plaques on the root surfaces (fraction of overlap 0.49±0.19) than to bacteria (0.072±0.052) (pbacteria that colocalized with metal(loid)s, Actinobacteria, known for their metal tolerance, had a higher correlation with both As and Fe than Alphaproteobacteria or Gammaproteobacteria. This method demonstrates how coupling these micro-techniques can expand our understanding of micro-scale interactions between roots, metal(loid)s and microbes, information that should lead to improved mechanistic models of metal(loid) speciation and fate. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. X-Ray Diffraction and X-Ray Fluorescent Analyses of Prehistoric Pottery Shards from Ulu Kelantan

    OpenAIRE

    Zuliskandar Ramli; Nik H.S.N. Abdul Rahman; Adnan Jusoh; Yunus Sauman

    2011-01-01

    Problem statement: X-Ray Diffraction (XRD) and X-Ray Fluorescent (XRF) were used in order to obtain mineralogical and elemental composition of seven pottery shards that have been unearthed during the excavation at Peraling Cave and Cha Cave in Ulu Kelantan, Malaysia. Approach: Peraling Cave and Cha Cave were prehistoric sites dating from 10, 000 BC which were inhabited by Hoabinhian people and then continuously used by people of Neolithic culture around 3000 BC. Results: Mineralogical and ele...

  2. Soft x-ray transmission grating spectrometer for X-ray Surveyor and smaller missions with high resolving power

    Science.gov (United States)

    Heilmann, Ralf K.; Bruccoleri, Alexander; Schattenburg, Mark; Kolodziejczak, jeffery; Gaskin, Jessica; O'Dell, Stephen L.

    2017-01-01

    A number of high priority subjects in astrophysics are addressed by a state-of-the-art soft x-ray grating spectrometer, e.g. the role of Active Galactic Nuclei in galaxy and star formation, characterization of the WHIM and the “missing baryon” problem, characterization of halos around the Milky Way and nearby galaxies, and stellar coronae and surrounding winds and disks. An Explorer-scale, large-area (A > 1,000 cm2), high resolving power (R > 3,000) soft x-ray grating spectrometer is highly feasible based on Critical-Angle Transmission (CAT) grating technology, even for telescopes with angular resolution of 5-10 arcsec. Significantly higher performance could be provided by a CAT grating spectrometer on an X-ray-Surveyor-type mission (A > 4,000 cm2, R > 5,000). CAT gratings combine advantages of blazed reflection gratings (high efficiency, use of higher orders) with those of transmission gratings (low mass, relaxed alignment tolerances and temperature requirements, transparent at higher energies) with minimal mission resource requirements. Blazing is achieved through grazing-incidence reflection off the smooth silicon grating bar sidewalls. Silicon is well matched to the soft x-ray band, and 30% absolute diffraction efficiency has been acheived with clear paths for further improvement. CAT gratings with sidewalls made of high-Z elements allow extension of blazing to higher energies and larger dispersion angles, enabling higher resolving power at shorter wavelengths. X-ray data from CAT gratings coated with a thin layer of platinum using atomic layer deposition demonstrate efficient blazing to higher energies and much larger blaze angles than possible with silicon alone. Measurements of the resolving power of a breadboard CAT grating spectrometer consisting of a Wolter-I slumped-glass focusing optic from GSFC and CAT gratings, taken at the MSFC Stray Light Facility, have demonstrated resolving power > 10,000. Thus currently fabricated CAT gratings are compatible

  3. Portable X-ray Fluorescence Unit for Analyzing Crime Scenes

    Science.gov (United States)

    Visco, A.

    2003-12-01

    Goddard Space Flight Center and the National Institute of Justice have teamed up to apply NASA technology to the field of forensic science. NASA hardware that is under development for future planetary robotic missions, such as Mars exploration, is being engineered into a rugged, portable, non-destructive X-ray fluorescence system for identifying gunshot residue, blood, and semen at crime scenes. This project establishes the shielding requirements that will ensure that the exposure of a user to ionizing radiation is below the U.S. Nuclear Regulatory Commission's allowable limits, and also develops the benchtop model for testing the system in a controlled environment.

  4. Trends in hard X-ray fluorescence mapping: environmental applications in the age of fast detectors.

    Science.gov (United States)

    Lombi, E; de Jonge, M D; Donner, E; Ryan, C G; Paterson, D

    2011-06-01

    Environmental samples are extremely diverse but share a tendency for heterogeneity and complexity. This heterogeneity poses methodological challenges when investigating biogeochemical processes. In recent years, the development of analytical tools capable of probing element distribution and speciation at the microscale have allowed this challenge to be addressed. Of these available tools, laterally resolved synchrotron techniques such as X-ray fluorescence mapping are key methods for the in situ investigation of micronutrients and inorganic contaminants in environmental samples. This article demonstrates how recent advances in X-ray fluorescence detector technology are bringing new possibilities to environmental research. Fast detectors are helping to circumvent major issues such as X-ray beam damage of hydrated samples, as dwell times during scanning are reduced. They are also helping to reduce temporal beamtime requirements, making particularly time-consuming techniques such as micro X-ray fluorescence (μXRF) tomography increasingly feasible. This article focuses on μXRF mapping of nutrients and metalloids in environmental samples, and suggests that the current divide between mapping and speciation techniques will be increasingly blurred by the development of combined approaches.

  5. Ultrafast Time Resolved X-ray Diffraction Studies of Laser Heated Metals and Semiconductors

    Science.gov (United States)

    Chen, Peilin; Tomov, I. V.; Rentzepis, P. M.

    1998-03-01

    Time resolved hard x-ray diffraction has been employed to study the dynamics of lattice structure deformation. When laser pulse energy is deposited in a material it generates a non uniform transient temperature distribution, which alters the lattice structure of the crystal. The deformed crystal lattice will change the angle of diffraction for a monochromatic x-ray beam. We report picosecond and nanosecond time resolved x-ray diffraction measurements of the lattice temperature distribution, transient structure and stress, in Pt (111) and GaAs (111) crystals, caused by pulsed UV laser irradiation. An ArF excimer laser operated at 300 Hz was used, both, to drive an x-ray diode with copper anode and heat the crystal. Bragg diffracted x-ray radiation was recorded by a direct imaging x-ray CCD. Changes in the diffraction patterns induced by a few millijouls pulse energy were observed at different time delays between the laser heating pulse and the x-ray probing pulse. A kinematical model for time resolved x-ray diffraction was used to analyze the experimental data. Good agreement between the measured and calculated scattered x-ray intensities profiles was achieved, indicating that detailed time resolved x-ray diffraction measurements can be made with nanosecond and picosecond resolution for small temperature changes. Our system can detect changes in the lattice spacing of about 10-3 A.

  6. Low Power X-Ray Photon Resolving Imaging Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Instruments employing X-ray detection are countless, in different sectors from medicine to industry and from basic to applied science. Given this importance, and...

  7. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop LUNA, a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for mineralogical analysis of regolith, rock...

  8. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for analysis of mineralogical composition of regolith,...

  9. Preparation of tissue samples for X-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chwiej, Joanna [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland)]. E-mail: jchwiej@novell.ftj.agh.edu.pl; Szczerbowska-Boruchowska, Magdalena [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Lankosz, Marek [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Wojcik, Slawomir [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Falkenberg, Gerald [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron, Notkestr. 85, Hamburg (Germany); Stegowski, Zdzislaw [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Setkowicz, Zuzanna [Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Ingardena 6, 30-060 Cracow (Poland)

    2005-12-15

    As is well-known, trace elements, especially metals, play an important role in the pathogenesis of many disorders. The topographic and quantitative elemental analysis of pathologically changed tissues may shed some new light on processes leading to the degeneration of cells in the case of selected diseases. An ideal and powerful tool for such purpose is the Synchrotron Microbeam X-ray Fluorescence technique. It enables the carrying out of investigations of the elemental composition of tissues even at the single cell level. The tissue samples for histopathological investigations are routinely fixed and embedded in paraffin. The authors try to verify the usefulness of such prepared tissue sections for elemental analysis with the use of X-ray fluorescence microscopy. Studies were performed on rat brain samples. Changes in elemental composition caused by fixation in formalin or paraformaldehyde and embedding in paraffin were examined. Measurements were carried out at the bending magnet beamline L of the Hamburger Synchrotronstrahlungslabor HASYLAB in Hamburg. The decrease in mass per unit area of K, Br and the increase in P, S, Fe, Cu and Zn in the tissue were observed as a result of the fixation. For the samples embedded in paraffin, a lower level of most elements was observed. Additionally, for these samples, changes in the composition of some elements were not uniform for different analyzed areas of rat brain.

  10. Determination of beryllium by using X-ray fluorescence spectrometry.

    Science.gov (United States)

    Zawisza, Beata

    2008-03-01

    X-ray fluorescence spectrometry method is subject to certain difficulties and inconveniences for the elements having the atomic number 9 or less. These difficulties become progressively more severe as the atomic number decreases, and are quite serious for beryllium, which is practically indeterminable directly by XRF. Therefore, an indirect determination of beryllium that is based on the evaluation of cobalt in the precipitate is taken into consideration. In the thesis below, there is a description of a new, simple, and precise method by selective precipitation using hexamminecobalt(III) chloride and ammonium carbonate-EDTA solution as a complexing agent for the determining of a trace amount of beryllium using X-ray fluorescence spectrometry. The optimum conditions for [Co(NH(3))(6)][Be(2)(OH)(3)(CO(3))(2)(H(2)O)(2)].(3)H(2)O complex formation were studied. The complex was collected on the membrane filter, and the Co Kalpha line was measured by XRF. The method presents the advantages of the sample preparation and the elimination of the matrix effects due to the thin film obtained. The detection limit of the proposed method is 0.2 mg of beryllium. The method was successfully applied to beryllium determination in copper/ beryllium/cobalt alloys.

  11. Time-resolved Rocking Curve Measurement Method using Laboratory X-ray Source

    OpenAIRE

    林, 雄二郎; 佐藤, 真伸; 古賀, 三井; 佃, 昇; 蔵元, 英一

    2005-01-01

    Fast x-ray detectors and fast signal processing devices have enabled to measure time dependence of x-ray diffraction intensity. Using a fast x-ray detection system, we have developed a time-resolved measurement method of rocking curves with a laboratory x-ray source. The method has been demonstrated for time-resolved rocking curves from an ultrasound-vibrated silicon crystal in MHz range. The measured rocking curves have been consistent with simulated curves based on the dynamical diffraction...

  12. Assessment of asthmatic inflammation using hybrid fluorescence molecular tomography-x-ray computed tomography

    Science.gov (United States)

    Ma, Xiaopeng; Prakash, Jaya; Ruscitti, Francesca; Glasl, Sarah; Stellari, Fabio Franco; Villetti, Gino; Ntziachristos, Vasilis

    2016-01-01

    Nuclear imaging plays a critical role in asthma research but is limited in its readings of biology due to the short-lived signals of radio-isotopes. We employed hybrid fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) for the assessment of asthmatic inflammation based on resolving cathepsin activity and matrix metalloproteinase activity in dust mite, ragweed, and Aspergillus species-challenged mice. The reconstructed multimodal fluorescence distribution showed good correspondence with ex vivo cryosection images and histological images, confirming FMT-XCT as an interesting alternative for asthma research.

  13. Progress in biomedical application of phase-contrast x-ray imaging and fluorescent x-ray CT

    Science.gov (United States)

    Takeda, Tohoru; Wu, Jin; Lwin, Thet-Thet; Yoneyama, Akio; Hirai, Yasuharu; Hyodo, Kazuyuki; Sunaguchi, Naoki; Yuasa, Tetsuya; Minami, Manabu; Kose, Katsumi; Akatsuka, Takao

    2006-08-01

    X-ray CT system with phase-contrast and fluorescent techniques are being developed for biomedical researches. We have applied these techniques for in-vivo and ex-vivo imaging. The phase-contrast x-ray CT enables to reveal the detailed morphological information of cancer lesion, and image quality of ex-vivo specimen was excellent comparing to 4.74T micro-MRI. Fluorescent x-ray CT could depict the functional information with high spatial resolution, and its image quality was almost the same as autoradiogram. Improvement of imaging system with much high-speed data acquisition will enable to use these techniques for new biomedical researches.

  14. X-ray fluorescence spectrometry and related techniques an introduction

    CERN Document Server

    Margui, Eva

    2013-01-01

    X-ray fluorescence spectrometry (XRF) is a well-established analytical technique for qualitative and quantitative elemental analysis of a wide variety of routine quality control and research samples. Among its many desirable features, it delivers true multi-element character analysis, acceptable speed and economy, easy of automation, and the capacity to analyze solid samples. This remarkable contribution to this field provides a comprehensive and up-to-date account of basic principles, recent developments, instrumentation, sample preparation procedures, and applications of XRF analysis. If you are a professional in materials science, analytic chemistry, or physics, you will benefit from not only the review of basics, but also the newly developed technologies with XRF. Those recent technological advances, including the design of low-power micro- focus tubes and novel X-ray optics and detectors, have made it possible to extend XRF to the analysis of low-Z elements and to obtain 2D or 3D information on a microme...

  15. Combined time-resolved laser fluorescence spectroscopy and extended X-ray absorption fine structure spectroscopy study on the complexation of trivalent actinides with chloride at T = 25-200 °C.

    Science.gov (United States)

    Skerencak-Frech, Andrej; Fröhlich, Daniel R; Rothe, Jörg; Dardenne, Kathy; Panak, Petra J

    2014-01-21

    The complexation of trivalent actinides (An(III)) with chloride is studied in the temperature range from 25 to 200 °C by spectroscopic methods. Time-resolved laser fluorescence spectroscopy (TRLFS) is applied to determine the thermodynamic data of Cm(III)-Cl(-) complexes, while extended X-ray absorption fine structure spectroscopy (EXAFS) is used to determine the structural data of the respective Am(III) complexes. The experiments are performed in a custom-built high-temperature cell which is modified for the respective spectroscopic technique. The TRLFS results show that at 25 °C the speciation is dominated mainly by the Cm(3+) aquo ion. Only a minor fraction of the CmCl(2+) complex is present in solution. As the temperature increases, the fraction of this species decreases further. Simultaneously, the fraction of the CmCl2(+) complex increases strongly with the temperature. Also, the CmCl3 complex is formed to a minor extent at T > 160 °C. The conditional stability constant log β'2 is determined as a function of the temperature and extrapolated to zero ionic strength with the specific ion interaction theory approach. The log β°2(T) values increase by more than 3 orders of magnitude in the studied temperature range. The temperature dependency of log β°2 is fitted by the extended van't Hoff equation to determine ΔrH°m, ΔrS°m, and ΔrC°p,m. The EXAFS results support these findings. The results confirm the absence of americium(III) chloride complexes at T = 25 and 90 °C ([Am(III)] = 10(-3) m, [Cl(-)] = 3.0 m), and the spectra are described by 9-10 oxygen atoms at a distance of 2.44-2.48 Å. At T = 200 °C two chloride ligands are present in the inner coordination sphere of Am(III) at a distance of 2.78 Å.

  16. Feasibility of x ray fluorescence for spent fuel safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, Corey Ross [Los Alamos National Laboratory; Mozin, Vladimir [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; White, Julia M [Los Alamos National Laboratory; Croft, Stephen [Los Alamos National Laboratory; Stafford, Alissa [TAMU; Charlton, William [TAMU

    2010-01-01

    Quantifying the Pu content in spent nuclear fuel is necessary for many reasons, in particular to verify that diversion or other illicit activities have not occurred. Therefore, safeguarding the world's nuclear fuel is paramount to responsible nuclear regulation and public acceptance, but achieving this goal presents many difficulties from both a technical and economic perspective. The Next Generation Safeguards Initiative (NGSI) of NA-24 is funding a large collaborative effort between multiple laboratories and universities to improve spent nuclear fuel safeguards methods and equipment. This effort involves the current work of modeling several different nondestructive assay (NDA) techniques. Several are being researched, because no single NDA technique, in isolation, has the potential to properly characterize fuel assemblies and offer a robust safeguards measure. The insights gained from this research, will be used to down-select from the original set a few of the most promising techniques that complement each other. The goal is to integrate the selected instruments to create an accurate measurement system for fuel verification that is also robust enough to detect diversions. These instruments will be fabricated and tested under realistic conditions. This work examines one of the NDA techniques; the feasibility of using x ray emission peaks from Pu and U to gather information about their relative quantities in the spent fuel. X Ray Fluorescence (XRF), is unique compared to the investigated techniques in that it is the only one able to give the elemental ratio of Pu to U, allowing the possibility of a Pu gram quantity for the assembly to be calculated. XRF also presents many challenges, mainly its low penetration, since the low energy x rays of interest are effectively shielded by the first few millimeters of a fuel pin. This paper will explore the results of Monte Carlo N-Particle eXtended (MCNPX) transport code calculations of spent fuel x ray peaks. The MCNPX

  17. Time Resolved X-Ray Spot Size Diagnostic

    CERN Document Server

    Richardson, Roger; Falabella, Steven; Guethlein, Gary; Raymond, Brett; Weir, John

    2005-01-01

    A diagnostic was developed for the determination of temporal history of an X-ray spot. A pair of thin (0.5 mm) slits image the x-ray spot to a fast scintillator which is coupled to a fast detector, thus sampling a slice of the X-Ray spot. Two other scintillator/detectors are used to determine the position of the spot and total forward dose. The slit signal is normalized to the dose and the resulting signal is analyzed to get the spot size. The position information is used to compensate for small changes due to spot motion and misalignment. The time resolution of the diagnostic is about 1 ns and measures spots from 0.5 mm to over 3 mm. The theory and equations used to calculate spot size and position are presented, as well as data. The calculations assume a symmetric, Gaussian spot. The spot data is generated by the ETA II accelerator, a 2kA, 5.5 MeV, 60ns electron beam focused on a Tantalum target. The spot generated is typically about 1 mm FWHM. Comparisons are made to an X-ray pinhole camera which images th...

  18. Simulation and application of micro X-ray fluorescence based on an ellipsoidal capillary

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jing; Li, Yude; Wang, Xingyi; Zhang, Xiaoyun; Lin, Xiaoyan, E-mail: yangjing_928@126.com

    2017-06-15

    Highlights: • A micro X-ray fluorescence setup based on an ellipsoidal capillary was presented. • The optimal parameters of ellipsoidal capillary were designed. • The 2D mapping image of biological sample was obtained. - Abstract: A micro X-ray fluorescence setup was presented, based on an ellipsoidal capillary and a traditional laboratorial X-ray source. Using Ray-tracing principle, we have simulated the transmission path of X-ray beam in the ellipsoidal capillary and designed the optimal parameters of the ellipsoidal capillary for the micro X-ray fluorescence setup. We demonstrate that ellipsoidal capillary is well suited as condenser for the micro X-ray fluorescence based on traditional laboratorial X-ray source. Furthermore, we obtain the 2D mapping image of the leaf blade sample by using the ellipsoidal capillary we designed.

  19. Using X-ray Fluorescence to Date Petroglyphs

    Science.gov (United States)

    McNeil, James

    2009-10-01

    Petroglyphs were created by ancient peoples of the Colorado Plateau who pecked figures of cultural or religious significance into the desert varnish, the ubiquitous dark patina covering the rock surfaces of the region. Manganese (Mn) is a significant elemental component of desert varnish that is often at trace levels in the substrate rock. As such, F. Lytle has shown that under certain conditions, it may be possible to estimate the age of petroglpyhs using Mn levels. In this work we use x-ray fluorescence to measure Mn levels in the desert varnish of petroglyphs and then use dated graffiti to attempt to calibrate the Mn level with age. Preliminary results from petroglyph panels in eastern Utah will be presented.

  20. X-ray fluorescence in research on Czech cultural monuments

    Energy Technology Data Exchange (ETDEWEB)

    Cechak, T.; Gerndt, J.; Kopecka, I.; Musilek, L. E-mail: musilek@fjfi.cvut.cz

    2004-01-01

    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.

  1. Determination of thorium by fluorescent x-ray spectrometry

    Science.gov (United States)

    Adler, I.; Axelrod, J.M.

    1955-01-01

    A fluorescent x-ray spectrographic method for the determination of thoria in rock samples uses thallium as an internal standard. Measurements are made with a two-channel spectrometer equipped with quartz (d = 1.817 A.) analyzing crystals. Particle-size effects are minimized by grinding the sample components with a mixture of silicon carbide and aluminum and then briquetting. Analyses of 17 samples showed that for the 16 samples containing over 0.7% thoria the average error, based on chemical results, is 4.7% and the maximum error, 9.5%. Because of limitations of instrumentation, 0.2% thoria is considered the lower limit of detection. An analysis can be made in about an hour.

  2. Materials characterization using micro-x-ray fluorescence elemental imaging.

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, G. J. (George J.); Miller, T. C. (Thomasin C.); Joseph, M. R. (Martha R.)

    2002-01-01

    Materials characterization continues to be a key challenge in a variety of programs. Although bulk elemental composition provides overall concentration of both major and trace elements, the distribution of these elements both on micro and macro scales can determine the performance and ultimately the physical properties of the materials. Hence elemental imaging can provide a new level of information for major and in some cases bulk trace concentrations of elements. Micro X-ray fluorescence (MXRF) offers unique capabilities in terms of elemental imaging. This approach is based on a meso scale level of resolution around 50 micrometer X-ray spot size. When coupled with a moveable stage, specimens several inches on a side can be imaged with surprising detail. In most instances, qualitative images are sufficient to illustrate the elemental heterogeneity. This information can then be used to determine if the material meets the desired physical characteristics and whether this is due to the observed heterogeneity or in spite of it. Several examples of elemental imaging will be presented. These will include the aging of polymers and the effects of residual organotin catalyst. The tin can be imaged using MXRF and has been show to be mobile within the polymeric material over time. Corrosion is a serious issue throughout the industrial world. A specific example of chloride attack on a metal, which creates problems in waste storage. Finally, MXRF used in high throughput screening in the development of novel peptide receptors will be shown. The advantage of MXRF is that no fluorescent tags need be added to the target molecules. This insures the unhindered interaction of the target molecules and allows for additional characterization using molecular spectroscopic techniques.

  3. Promising X-ray fluorescence tests for superconducting tunneljunction detector

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, Stephan; Robinson, Arthur L.

    2001-05-15

    Scientists in the Physical Biosciences Division of the Ernest Orlando Berkeley National Laboratory (Berkeley Lab) studying transition metals in proteins with fluorescence-detected L-edge absorption spectroscopy have found the measurements to be extremely challenging. The difficulty is that the metal centers are present in very dilute concentrations so that their weak fluorescence is often obscured by strong background signals carbon and oxygen. To solve this problem, the Berkeley group has been working with researchers from the Advanced Detector Group at the Lawrence Livermore National Laboratory on an energy-dispersive superconducting tunnel junction x-ray detector. These devices in principle have the energy resolution needed to reveal the metal signal. The most recent results with the latest version of the detector on Beamline 4.0.1-2 at the Advanced Light Source (ALS) illustrate the promise of the cryogenic detector strategy not only for this application but also for spectroscopy of other types of dilute samples. Transition-metal complexes are key elements in many biologically important processes that are catalyzed by proteins (enzymes), photosynthesis being a prime example. The changes in that occur in electronic structure throughout a catalytic cycle are the subject of much research aimed at understanding the mechanisms of these processes. L-edge x-ray spectroscopy offers several advantages relative to the more common K-edge techniques, since it involves allowed transitions to the d-orbitals associated with metal-ligand bonding. It also has a rich multiplet structure interpretable by theory and higher spectral resolution.

  4. On the theory of time-resolved x-ray diffraction

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2008-01-01

    We derive the basic theoretical formulation for X-ray diffraction with pulsed fields, using a fully quantized description of light and matter. Relevant time scales are discussed for coherent as well as incoherent X-ray pulses, and we provide expressions to be used for calculation...... of the experimental diffraction signal for both types of X-ray sources. We present a simple analysis of time-resolved X-ray scattering for direct bond breaking in diatomic molecules. This essentially analytical approach highlights the relation between the signal and the time-dependent quantum distribution...

  5. An edge-on charge-transfer design for energy-resolved x-ray detection.

    Science.gov (United States)

    Shi, Zaifeng; Yang, Haoyu; Cong, Wenxiang; Wang, Ge

    2016-06-01

    As an x-ray beam goes through the human body, it will collect important information via interaction with tissues. Since this interaction is energy-sensitive, the state-of-the-art spectral CT technologies provide higher quality images of biological tissues with x-ray energy information (or spectral information). With existing energy-integrating technologies, a large fraction of energy information is ignored in the x-ray detection process. Although the recently proposed photon-counting technology promises to achieve higher image quality at a lower radiation dose, it suffers from limitations in counting rate, performance uniformity, and fabrication cost. In this paper, we focus on an alternative approach to resolve the energy distribution of transmitted x-ray photons. First, we analyze the x-ray attenuation in a silicon substrate and describe a linear approximation model for x-ray detection. Then, we design an edge-on architecture based on the proposed energy-resolving model. In our design, the x-ray-photon-induced charges are transferred sequentially resembling the working process of a CCD camera. Finally, we numerically evaluate the linear approximation of x-ray attenuation and derive the energy distribution of x-ray photons. Our simulation results show that the proposed energy-sensing approach is feasible and has the potential to complement the photon-counting technology.

  6. An edge-on charge-transfer design for energy-resolved x-ray detection

    Science.gov (United States)

    Shi, Zaifeng; Yang, Haoyu; Cong, Wenxiang; Wang, Ge

    2016-06-01

    As an x-ray beam goes through the human body, it will collect important information via interaction with tissues. Since this interaction is energy-sensitive, the state-of-the-art spectral CT technologies provide higher quality images of biological tissues with x-ray energy information (or spectral information). With existing energy-integrating technologies, a large fraction of energy information is ignored in the x-ray detection process. Although the recently proposed photon-counting technology promises to achieve higher image quality at a lower radiation dose, it suffers from limitations in counting rate, performance uniformity, and fabrication cost. In this paper, we focus on an alternative approach to resolve the energy distribution of transmitted x-ray photons. First, we analyze the x-ray attenuation in a silicon substrate and describe a linear approximation model for x-ray detection. Then, we design an edge-on architecture based on the proposed energy-resolving model. In our design, the x-ray-photon-induced charges are transferred sequentially resembling the working process of a CCD camera. Finally, we numerically evaluate the linear approximation of x-ray attenuation and derive the energy distribution of x-ray photons. Our simulation results show that the proposed energy-sensing approach is feasible and has the potential to complement the photon-counting technology.

  7. Few-femtosecond time-resolved measurements of X-ray free-electron lasers.

    Science.gov (United States)

    Behrens, C; Decker, F-J; Ding, Y; Dolgashev, V A; Frisch, J; Huang, Z; Krejcik, P; Loos, H; Lutman, A; Maxwell, T J; Turner, J; Wang, J; Wang, M-H; Welch, J; Wu, J

    2014-04-30

    X-ray free-electron lasers, with pulse durations ranging from a few to several hundred femtoseconds, are uniquely suited for studying atomic, molecular, chemical and biological systems. Characterizing the temporal profiles of these femtosecond X-ray pulses that vary from shot to shot is not only challenging but also important for data interpretation. Here we report the time-resolved measurements of X-ray free-electron lasers by using an X-band radiofrequency transverse deflector at the Linac Coherent Light Source. We demonstrate this method to be a simple, non-invasive technique with a large dynamic range for single-shot electron and X-ray temporal characterization. A resolution of less than 1 fs root mean square has been achieved for soft X-ray pulses. The lasing evolution along the undulator has been studied with the electron trapping being observed as the X-ray peak power approaches 100 GW.

  8. Ultrafast structural dynamics studied by kilohertz time-resolved x-ray diffraction

    Institute of Scientific and Technical Information of China (English)

    郭鑫; 江舟亚; 陈龙; 陈黎明; 辛建国; 陈洁

    2015-01-01

    Ultrashort multi-keV x-ray pulses are generated by electron plasma produced by the irradiation of femtosecond pulses on metals. These sub-picosecond x-ray pulses have extended the field of x-ray spectroscopy into the femtosecond time domain. However, pulse-to-pulse instability and long data acquisition time restrict the application of ultrashort x-ray systems operating at low repetition rates. Here we report on the performance of a femtosecond laser plasma-induced hard x-ray source that operates at 1-kHz repetition rate, and provides a flux of 2.0 × 1010 photons/s of Cu Kα radiation. Using this system for time-resolved x-ray diffraction experiments, we record in real time, the transient processes and structural changes induced by the interaction of 400-nm femtosecond pulse with the surface of a 200-nm thick Au (111) single crystal.

  9. Fast x-ray fluorescence microtomography of hydrated biological samples.

    Directory of Open Access Journals (Sweden)

    Enzo Lombi

    Full Text Available Metals and metalloids play a key role in plant and other biological systems as some of them are essential to living organisms and all can be toxic at high concentrations. It is therefore important to understand how they are accumulated, complexed and transported within plants. In situ imaging of metal distribution at physiological relevant concentrations in highly hydrated biological systems is technically challenging. In the case of roots, this is mainly due to the possibility of artifacts arising during sample preparation such as cross sectioning. Synchrotron x-ray fluorescence microtomography has been used to obtain virtual cross sections of elemental distributions. However, traditionally this technique requires long data acquisition times. This has prohibited its application to highly hydrated biological samples which suffer both radiation damage and dehydration during extended analysis. However, recent advances in fast detectors coupled with powerful data acquisition approaches and suitable sample preparation methods can circumvent this problem. We demonstrate the heightened potential of this technique by imaging the distribution of nickel and zinc in hydrated plant roots. Although 3D tomography was still impeded by radiation damage, we successfully collected 2D tomograms of hydrated plant roots exposed to environmentally relevant metal concentrations for short periods of time. To our knowledge, this is the first published example of the possibilities offered by a new generation of fast fluorescence detectors to investigate metal and metalloid distribution in radiation-sensitive, biological samples.

  10. A Spatially Resolved X-ray Image of a Star Like the Sun.

    Science.gov (United States)

    Schmitt, J H; Kürster, M

    1993-10-08

    Observations made with the x-ray satellite ROSAT (Roentgen Satellite) have produced the first spatially resolved x-ray image of a corona around a star like our sun. The star is the secondary in the eclipsing binary system alpha Coronae Borealis (CrB), which consists of one star of spectral type A0V and one of type G5V. The x-ray light curve of alpha CrB shows a total x-ray eclipse during secondary optical minimum, with the G star behind the A star. The totality of the eclipse demonstrates that the A-type component in alpha CrB is x-ray dark and that the x-ray flux arises exclusively from the later-type companion. The x-ray eclipse ingress and egress are highly asymmetric compared with the optical eclipse, indicating a highly asymmetric x-ray intensity distribution on the surface of the G star. From a detailed modeling of the ingress and egress of the x-ray light curve, an eclipse map of the G star was constructed by a method based on an optimization by simulated annealing.

  11. Computational time-resolved and resonant x-ray scattering of strongly correlated materials

    Energy Technology Data Exchange (ETDEWEB)

    Bansil, Arun [Northeastern Univ., Boston, MA (United States)

    2016-11-09

    Basic-Energy Sciences of the Department of Energy (BES/DOE) has made large investments in x-ray sources in the U.S. (NSLS-II, LCLS, NGLS, ALS, APS) as powerful enabling tools for opening up unprecedented new opportunities for exploring properties of matter at various length and time scales. The coming online of the pulsed photon source, literally allows us to see and follow the dynamics of processes in materials at their natural timescales. There is an urgent need therefore to develop theoretical methodologies and computational models for understanding how x-rays interact with matter and the related spectroscopies of materials. The present project addressed aspects of this grand challenge of x-ray science. In particular, our Collaborative Research Team (CRT) focused on developing viable computational schemes for modeling x-ray scattering and photoemission spectra of strongly correlated materials in the time-domain. The vast arsenal of formal/numerical techniques and approaches encompassed by the members of our CRT were brought to bear through appropriate generalizations and extensions to model the pumped state and the dynamics of this non-equilibrium state, and how it can be probed via x-ray absorption (XAS), emission (XES), resonant and non-resonant x-ray scattering, and photoemission processes. We explored the conceptual connections between the time-domain problems and other second-order spectroscopies, such as resonant inelastic x-ray scattering (RIXS) because RIXS may be effectively thought of as a pump-probe experiment in which the incoming photon acts as the pump, and the fluorescent decay is the probe. Alternatively, when the core-valence interactions are strong, one can view K-edge RIXS for example, as the dynamic response of the material to the transient presence of a strong core-hole potential. Unlike an actual pump-probe experiment, here there is no mechanism for adjusting the time-delay between the pump and the probe. However, the core hole

  12. Energy dispersive x-ray fluorescence analyzer with several x-ray tubes

    Science.gov (United States)

    Borisov, G. I.; Kondratenko, R. I.; Mikhin, V. A.; Odinov, B. V.; Pukhov, A. V.

    2005-07-01

    X-ray flurescent analyzer (XFA) has been developed and fabricated for determining sulphur, vanadium and nickel in oil. The instrument is equipped with three x-ray tubes with transmission Ti, Cu and Ag anodes, and aluminum, copper, and germanium filters, respectively, and one common switchable power supply. To excite characteristic radiation of determined elements, the characteristic radiation of the tube anode (titan, copper) is used, or the charactersitic radiation of the filter (germanium). XFA is fitted with one small-size electrically cooled semiconductor detector. The measuring device is based on a wide-angle geometry of characteristic radiation excitation and registration, where the x-ray tube focus illuminates the sample, and the registering detector 'sees' the illuminated area within the plane angle of 90° (it corresponds to 0.146 of 4p). Under such geometry, the dependence of the count rate for excited characteristic photons on the position of sample under study has a smooth maximum in the calculated sample position point. For one, the rate count changes by less than 1%. Quantitative results are obtained through the regression method. The instrument underwent metrology testing. It is designed for operation both in the laboratory and industrial environment. The instrument has been delivered for operation to the "Druzhba" pipeline.

  13. Flow method and apparatus for screening chemicals using micro x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Miller, Thomasin C. (Bartlesville, OK); Lewis, Cris (Los Alamos, NM); Mahan, Cynthia A. (Los Alamos, NM); Wells, Cyndi A. (Los Alamos, NM)

    2011-04-26

    Method and apparatus for screening chemicals using micro x-ray fluorescence. A method for screening a mixture of potential pharmaceutical chemicals for binding to at least one target binder involves flow separating a solution of chemicals and target binders into separated components, exposing them to an x-ray excitation beam, detecting x-ray fluorescence signals from the components, and determining from the signals whether or not a binding event between a chemical and target binder has occurred.

  14. Flow method and apparatus for screening chemicals using micro x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Miller, Thomasin C. (Bartlesville, OK); Lewis, Cris (Los Alamos, NM); Mahan, Cynthia A. (Los Alamos, NM); Wells, Cyndi A. (Los Alamos, NM)

    2009-04-14

    Method and apparatus for screening chemicals using micro x-ray fluorescence. A method for screening a mixture of potential pharmaceutical chemicals for binding to at least one target binder involves flow-separating a solution of chemicals and target binders into separated components, exposing them to an x-ray excitation beam, detecting x-ray fluorescence signals from the components, and determining from the signals whether or not a binding event between a chemical and target binder has occurred.

  15. Capturing molecular structural dynamics by 100 ps time-resolved X-ray absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Tokushi [Department of Materials Science, Tokyo Institute of Technology, 2-12-1-H61 Ohokayama, Meguro-ku, Tokyo 152-8551 (Japan); Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Nozawa, Shunsuke; Ichiyanagi, Kohei [Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Tomita, Ayana [Department of Materials Science, Tokyo Institute of Technology, 2-12-1-H61 Ohokayama, Meguro-ku, Tokyo 152-8551 (Japan); Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Chollet, Matthieu [Department of Materials Science, Tokyo Institute of Technology, 2-12-1-H61 Ohokayama, Meguro-ku, Tokyo 152-8551 (Japan); Ichikawa, Hirohiko [Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Fujii, Hiroshi [Institute for Molecular Science and Okazaki Institute for Integrative Bioscience, Myodaiji, Okazaki 444-8787 (Japan); Adachi, Shin-ichi [Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Koshihara, Shin-ya, E-mail: skoshi@cms.titech.ac.jp [Department of Materials Science, Tokyo Institute of Technology, 2-12-1-H61 Ohokayama, Meguro-ku, Tokyo 152-8551 (Japan); Non-Equilibrium Dynamics Project, ERATO, Japan Science and Technology Agency, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Frontier Research Center, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551 (Japan)

    2009-01-01

    An experimental set-up for time-resolved X-ray absorption spectroscopy with 100 ps time resolution at beamline NW14A at the Photon Factory Advanced Ring is presented. An experimental set-up for time-resolved X-ray absorption spectroscopy with 100 ps time resolution at beamline NW14A at the Photon Factory Advanced Ring is presented. The X-ray positional active feedback to crystals in a monochromator combined with a figure-of-merit scan of the laser beam position has been utilized as an essential tool to stabilize the spatial overlap of the X-ray and laser beams at the sample position. As a typical example, a time-resolved XAFS measurement of a photo-induced spin crossover reaction of the tris(1,10-phenanthrorine)iron(II) complex in water is presented.

  16. Combined synchrotron X-ray tomography and X-ray powder diffraction using a fluorescing metal foil.

    Science.gov (United States)

    Kappen, P; Arhatari, B D; Luu, M B; Balaur, E; Caradoc-Davies, T

    2013-06-01

    This study realizes the concept of simultaneous micro-X-ray computed tomography and X-ray powder diffraction using a synchrotron beamline. A thin zinc metal foil was placed in the primary, monochromatic synchrotron beam to generate a divergent wave to propagate through the samples of interest onto a CCD detector for tomographic imaging, thus removing the need for large beam illumination and high spatial resolution detection. Both low density materials (kapton tubing and a piece of plant) and higher density materials (Egyptian faience) were investigated, and elemental contrast was explored for the example of Cu and Ni meshes. The viability of parallel powder diffraction using the direct beam transmitted through the foil was demonstrated. The outcomes of this study enable further development of the technique towards in situ tomography∕diffraction studies combining micrometer and crystallographic length scales, and towards elemental contrast imaging and reconstruction methods using well defined fluorescence outputs from combinations of known fluorescence targets (elements).

  17. Temporal and Spectral Resolved Measurement of Soft X-ray From Ultrashort Pulse Laser Produced Plasma

    Institute of Scientific and Technical Information of China (English)

    W.Theobald; L.Veisz; H.Schwoerer; R.Sauerbrey; X.Z.Tang

    2001-01-01

    Ultrashort laser pulse produced plasmas are powerful sources of incoherent XUV/soft X-ray radiation and have important applications range from microscopy to lithography. Adding a prepulse is one possible way to enhance soft X-ray emission. The experiment is performed on the Jena 10 TW laser system in IOQ, Germany. The main purpose is to measure the time-resolved soft X-ray spectrum, and study how a prepulse play an important role and enhance the X-ray emission as well as and pulse duration. We clarified the temporal behavior of X-ray emission from quartz plasma produced by intensive femtosecond 800 nm laser pulse, and obtained a quantitative pictures of the

  18. X-ray Fluorescence Measurements of Turbulent Methane-Oxygen Shear Coaxial Flames (Briefing Charts)

    Science.gov (United States)

    2015-03-01

    Briefing Charts 3. DATES COVERED (From - To) March 2015-May 2015 4. TITLE AND SUBTITLE X-ray Fluorescence Measurements of Turbulent Methane -Oxygen Shear...1 DISTRIBUTION A: Approved for public release; distribution unlimited. Clearance # X-ray Fluorescence Measurements of Turbulent Methane -Oxygen Shear

  19. Water analysis via portable X-ray fluorescence spectrometry

    Science.gov (United States)

    Pearson, Delaina; Chakraborty, Somsubhra; Duda, Bogdan; Li, Bin; Weindorf, David C.; Deb, Shovik; Brevik, Eric; Ray, D. P.

    2017-01-01

    Rapid, in-situ elemental water analysis would be an invaluable tool in studying polluted and/or salt-impacted waters. Analysis of water salinity has commonly used electrical conductance (EC); however, the identity of the elements responsible for the salinity are not revealed using EC. Several studies have established the viability of using portable X-ray fluorescence (PXRF) spectrometry for elemental data analysis of soil, sediment, and other matrices. However, the accuracy of PXRF is known to be affected while scanning moisture-laden soil samples. This study used PXRF elemental data in water samples to predict water EC. A total of 256 water samples, from 10 different countries were collected and analyzed via PXRF, inductively coupled plasma atomic emission spectroscopy (ICP-AES), and a digital salinity bridge. The PXRF detected some elements more effectively than others, but overall results indicated that PXRF can successfully predict water EC via quantifying Cl in water samples (validation R2 and RMSE of 0.77 and 0.95 log μS cm-1, respectively). The findings of this study elucidated the potential of PXRF for future analysis of pollutant and/or metal contaminated waters.

  20. Portable x-ray fluorescence spectrometer. Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    This report describes the application of portable X-ray fluorescence (XRF) spectrometry to characterize materials related to deactivation and decommissioning (D and D) of contaminated facilities. Two portable XRF instruments manufactured by TN Spectrace were used in a technology evaluation as part of the Large-Scale Demonstration Project (LSDP) held at the Chicago Pile-5 Research Reactor (CP-5) located at Argonne National Laboratory (ANL). The LSDP is sponsored by the US Department of Energy (DOE), Office of Science and Technology, Deactivation and Decommissioning Focus Are (DDFA). The objective of the LSDP is to demonstrate innovative technologies or technology applications potentially beneficial to the D and D of contaminated facilities. The portable XRF technology offers several potential benefits for rapid characterization of facility components and contaminants, including significant cost reduction, fast turnaround time,a nd virtually no secondary waste. Field work for the demonstration of the portable XRF technology was performed from August 28--September 3, 1996 and October 30--December 13, 1996.

  1. Energy-resolved X-ray detectors: the future of diagnostic imaging

    Directory of Open Access Journals (Sweden)

    Pacella D

    2015-01-01

    Full Text Available Danilo Pacella ENEA-Frascati, Rome, Italy Abstract: This paper presents recent progress in the field of X-ray detectors, which could play a role in medical imaging in the near future, with special attention to the new generation of complementary metal-oxide semiconductor (C-MOS imagers, working in photon counting, that opened the way to the energy-resolved X-ray imaging. A brief description of the detectors used so far in medical imaging (photographic films, imaging plates, flat panel detectors, together with the most relevant imaging quality parameters, shows differences between, and advantages of these new C-MOS imagers. X-ray energy-resolved imaging is very attractive not only for the increase of contrast but even for the capability of detecting the nature and composition of the material or tissue to be investigated. Since the X-ray absorption coefficients of the different parts or organs of the patient (object are strongly dependent on the X-ray photon energy, this multienergy ("colored" X-ray imaging could increase enormously the probing capabilities. While dual-energy imaging is now a reality in medical practice, multienergy is still in its early stage, but a promising research activity. Based on this new technique of color X-ray imaging, the entire scheme of source–object–detector could be revised in the future, optimizing spectrum and detector to the nature and composition of the target to be investigated. In this view, a transition to a set of monoenergetic X-ray lines, suitably chosen in energy and intensity, could be envisaged, instead of the present continuous spectra. Keywords: X-ray detectors, X-ray medical imaging, C-MOS imagers, dual and multienergy CT

  2. Calibration of a time-resolved hard-x-ray detector using radioactive sources

    Science.gov (United States)

    Stoeckl, C.; Theobald, W.; Regan, S. P.; Romanofsky, M. H.

    2016-11-01

    A four-channel, time-resolved, hard x-ray detector (HXRD) has been operating at the Laboratory for Laser Energetics for more than a decade. The slope temperature of the hot-electron population in direct-drive inertial confinement fusion experiments is inferred by recording the hard x-ray radiation generated in the interaction of the electrons with the target. Measuring the energy deposited by hot electrons requires an absolute calibration of the hard x-ray detector. A novel method to obtain an absolute calibration of the HXRD using single photons from radioactive sources was developed, which uses a thermoelectrically cooled, low-noise, charge-sensitive amplifier.

  3. Local terahertz field enhancement for time-resolved x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Kozina, M.; /SLAC; Pancaldi, M.; /CIC nanoGUNE /Stockholm U.; Bernhard, C.; /Fribourg U.; Driel, T.van; Glownia, J.M.; /SLAC; Marsik, P.; /Fribourg U.; Radovic, M.; Vaz, C.A.F.; /PLS, SLS; Zhu, D.; /SLAC; Bonetti, S.; /Stockholm U.; Staub, U.; /PLS, SLS; Hoffmann, M.C.; /SLAC

    2017-02-20

    We report local field strength enhancement of single-cycle terahertz (THz) pulses in an ultrafast time-resolved x-ray diffraction experiment. We show that patterning the sample with gold microstructures increases the THz field without changing the THz pulse shape or drastically affecting the quality of the x-ray diffraction pattern. We find a five-fold increase in THz-induced x-ray diffraction intensity change in the presence of microstructures on a SrTiO3 thin-film sample.

  4. X-ray diffraction in temporally and spatially resolved biomolecular science.

    Science.gov (United States)

    Helliwell, John R; Brink, Alice; Kaenket, Surasak; Starkey, Victoria Laurina; Tanley, Simon W M

    2015-01-01

    Time-resolved Laue protein crystallography at the European Synchrotron Radiation Facility (ESRF) opened up the field of sub-nanosecond protein crystal structure analyses. There are a limited number of such time-resolved studies in the literature. Why is this? The X-ray laser now gives us femtosecond (fs) duration pulses, typically 10 fs up to ∼50 fs. Their use is attractive for the fastest time-resolved protein crystallography studies. It has been proposed that single molecules could even be studied with the advantage of being able to measure X-ray diffraction from a 'crystal lattice free' single molecule, with or without temporal resolved structural changes. This is altogether very challenging R&D. So as to assist this effort we have undertaken studies of metal clusters that bind to proteins, both 'fresh' and after repeated X-ray irradiation to assess their X-ray-photo-dynamics, namely Ta6Br12, K2PtI6 and K2PtBr6 bound to a test protein, hen egg white lysozyme. These metal complexes have the major advantage of being very recognisable shapes (pseudo spherical or octahedral) and thereby offer a start to (probably very difficult) single molecule electron density map interpretations, both static and dynamic. A further approach is to investigate the X-ray laser beam diffraction strength of a well scattering nano-cluster; an example from nature being the iron containing ferritin. Electron crystallography and single particle electron microscopy imaging offers alternatives to X-ray structural studies; our structural studies of crustacyanin, a 320 kDa protein carotenoid complex, can be extended either by electron based techniques or with the X-ray laser representing a fascinating range of options. General outlook remarks concerning X-ray, electron and neutron macromolecular crystallography as well as 'NMR crystallography' conclude the article.

  5. Romanian medieval earring analysis by X-ray fluorescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Therese, Laurent; Guillot, Philippe, E-mail: philippe.guillot@univ-jfc.fr [Laboratoire Diagnostics des Plasmas, CUFR J.F.C, Albi (France); Muja, Cristina [Laboratoire Diagnostics des Plasmas, CUFR J.F.C, Albi (France); Faculty of Biology, University of Bucharest (Romania); Vasile Parvan Institute of Archaeology, Bucharest, (Romania)

    2011-07-01

    Full text: Several instrumental techniques of elemental analysis are now used for the characterization of archaeological materials. The combination between archaeological and analytical information can provide significant knowledge on the constituting material origin, heritage authentication and restoration, provenance, migration, social interaction and exchange. Surface mapping techniques such as X-Ray Fluorescence have become a powerful tool for obtaining qualitative and semi-quantitative information about the chemical composition of cultural heritage materials, including metallic archaeological objects. In this study, the material comes from the Middle Age cemetery of Feldioara (Romania). The excavation of the site located between the evangelical church and the parsonage led to the discovery of several funeral artifacts in 18 graves among a total of 127 excavated. Even if the inventory was quite poor, some of the objects helped in establishing the chronology. Six anonymous Hungarian denarii (silver coins) were attributed to Geza II (1141-1161) and Stefan III (1162-1172), placing the cemetery in the second half of the XII century. This period was also confirmed by three loop shaped earrings with the end in 'S' form (one small and two large earrings). The small earring was found during the excavation in grave number 86, while the two others were discovered together in grave number 113. The anthropological study shown that skeletons excavated from graves 86 and 113 belonged respectively to a child (1 individual, medium level preservation, 9 months +/- 3 months) and to an adult (1 individual). In this work, elemental mapping were obtained by X-ray fluorescence (XRF) technique from Jobin Yvon Horiba XGT-5000 instrument offering detailed elemental images with a spatial resolution of 100{mu}m. The analysis revealed that the earrings were composed of copper, zinc and tin as major elements. Minor elements were also determined. The comparison between the two

  6. Feasibility study of total reflection X-ray fluorescence analysis using a liquid metal jet X-ray tube

    Energy Technology Data Exchange (ETDEWEB)

    Maderitsch, A.; Smolek, S. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria); Wobrauschek, P., E-mail: wobi@ati.ac.at [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria); Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria); Takman, P. [Excillum AB, Finlandsgatan 14, 164 74 Kista (Sweden)

    2014-09-01

    Total reflection X-ray spectroscopy (TXRF) is a powerful analytical technique for qualitative and quantitative analysis of trace and ultratrace elements in a sample with lower limits of detection (LLDs) of pg/g to ng/g in concentration and absolute high fg levels are attainable. Several X-ray sources, from low power (few W), 18 kW rotating anodes to synchrotron radiation, are in use for the excitation and lead accordingly to their photon flux delivered on the sample the detection limits specified. Not only the power, but also the brilliance and focal shape are of importance for TXRF. A microfocus of 50–100 μm spot size or the line focus of diffraction tubes is best suited. Excillum developed a new approach in the design of a source: the liquid metal jet anode. In this paper the results achieved with this source are described. A versatile TXRF spectrometer with vacuum chamber designed at Atominstitut was used for the experiments. A multilayer monochromator selecting the intensive Ga-Kα radiation was taken and the beam was collimated by 50 μm slits. Excellent results regarding geometric beam stability, high fluorescence intensities and low background were achieved leading to detection limits in the high fg range for Ni. A 100 mm{sup 2} silicon drift detector (SDD) collimated to 80 mm{sup 2} was used to collect the fluorescence radiation. The results from measurements on single element samples are presented. - Highlights: • Using a new X-ray source for TXRF • Liquid metal jet X-ray source from Excillum • Offers improvements for lab based TXRF spectrometers • Can also be important for related techniques.

  7. Enhanced x-ray resolving power achieved behind the focal circles of Cauchois spectrometers.

    Science.gov (United States)

    Seely, John F; Hudson, Lawrence T; Holland, Glenn E; Henins, Albert

    2008-05-20

    Maintaining high resolving power is a primary challenge in hard x-ray spectroscopy of newly developed bright and transient x-ray sources such as laser-produced plasmas. To address this challenge, the line widths in x-ray spectra with energies in the 17 keV to 70 keV range were recorded by positioning the detectors on and behind the focal circles of Cauchois type transmission-crystal spectrometers. To analyze and understand the observed line widths, we developed a geometrical model that accounts for source broadening and various instrumental broadening mechanisms. The x-ray sources were laboratory Mo or W electron-bombarded anodes, and the spectra were recorded on photostimulable phosphor image plates. For these relatively small x-ray sources, it was found that when the detector was placed on or near the focal circle, the line widths were dominated by the effective spatial resolution of the detector. When the detector was positioned beyond the focal circle, the line widths were determined primarily by source-size broadening. Moreover, the separation between the spectral lines increased with distance behind the focal circle faster than the line widths, resulting in increased resolving power with distance. Contributions to line broadenings caused by the crystal thickness, crystal rocking curve width, geometrical aberrations, and natural widths of the x-ray transitions were in all cases smaller than detector and source broadening, but were significant for some spectrometer geometries. The various contributions to the line widths, calculated using simple analytical expressions, were in good agreement with the measured line widths for a variety of spectrometer and source conditions. These modeling and experimental results enable the design of hard x-ray spectrometers that are optimized for high resolving power and for the measurement of the x-ray source size from the line widths recorded behind the focal circle.

  8. Time-resolved X-ray spectroscopies of chemical systems: New perspectives.

    Science.gov (United States)

    Chergui, Majed

    2016-05-01

    The past 3-5 years have witnessed a dramatic increase in the number of time-resolved X-ray spectroscopic studies, mainly driven by novel technical and methodological developments. The latter include (i) the high repetition rate optical pump/X-ray probe studies, which have greatly boosted the signal-to-noise ratio for picosecond (ps) X-ray absorption spectroscopy studies, while enabling ps X-ray emission spectroscopy (XES) at synchrotrons; (ii) the X-ray free electron lasers (XFELs) are a game changer and have allowed the first femtosecond (fs) XES and resonant inelastic X-ray scattering experiments to be carried out; (iii) XFELs are also opening the road to the development of non-linear X-ray methods. In this perspective, I will mainly focus on the most recent technical developments and briefly address some examples of scientific questions that have been addressed thanks to them. I will look at the novel opportunities in the horizon.

  9. Direct observation of ultrafast atomic motion using time-resolved X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Shymanovich, U.

    2007-11-13

    This thesis is dedicated to the study of the atomic motion in laser irradiated solids on a picosecond to subpicosecond time-scale using the time-resolved X-ray diffraction technique. In the second chapter, the laser system, the laser-plasma based X-ray source and the experimental setup for optical pump / X-ray probe measurements were presented. Chapter 3 is devoted to the characterization and comparison of different types of X-ray optics. Chapter 4 presented the time-resolved X-ray diffraction experiments performed for this thesis. The first two sections of this chapter discuss the measurements of initially unexpected strain-induced transient changes of the integrated reflectivity of the X-ray probe beam. The elimination of the strain-induced transient changes of the integrated reflectivity represented an important prerequisite to perform the study of lattice heating in Germanium after femtosecond optical excitation by measuring the transient Debye-Waller effect. The third section describes the investigations of acoustic waves upon ultrafast optical excitation and discusses the two different pressure contributions driving them: the thermal and the electronic ones. (orig.)

  10. A table-top femtosecond time-resolved soft x-ray transient absorption spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Leone, Stephen; Loh, Zhi-Heng; Khalil, Munira; Correa, Raoul E.; Leone, Stephen R.

    2008-05-21

    A laser-based, table-top instrument is constructed to perform femtosecond soft x-ray transient absorption spectroscopy. Ultrashort soft x-ray pulses produced via high-order harmonic generation of the amplified output of a femtosecond Ti:sapphire laser system are used to probe atomic core-level transient absorptions in atoms and molecules. The results provide chemically specific, time-resolved dynamics with sub-50-fs time resolution. In this setup, high-order harmonics generated in a Ne-filled capillary waveguide are refocused by a gold-coated toroidal mirror into the sample gas cell, where the soft x-ray light intersects with an optical pump pulse. The transmitted high-order harmonics are spectrally dispersed with a home-built soft x-ray spectrometer, which consists of a gold-coated toroidal mirror, a uniform-line spaced plane grating, and a soft x-ray CCD camera. The optical layout of the instrument, design of the soft x-ray spectrometer, and spatial and temporal characterization of the high-order harmonics are described. Examples of static and time-resolved photoabsorption spectra collected on this apparatus are presented.

  11. Thin film growth studies using time-resolved x-ray scattering

    Science.gov (United States)

    Kowarik, Stefan

    2017-02-01

    Thin-film growth is important for novel functional materials and new generations of devices. The non-equilibrium growth physics involved is very challenging, because the energy landscape for atomic scale processes is determined by many parameters, such as the diffusion and Ehrlich-Schwoebel barriers. We review the in situ real-time techniques of x-ray diffraction (XRD), x-ray growth oscillations and diffuse x-ray scattering (GISAXS) for the determination of structure and morphology on length scales from Å to µm. We give examples of time resolved growth experiments mainly from molecular thin film growth, but also highlight growth of inorganic materials using molecular beam epitaxy (MBE) and electrochemical deposition from liquids. We discuss how scaling parameters of rate equation models and fundamental energy barriers in kinetic Monte Carlo methods can be determined from fits of the real-time x-ray data.

  12. A high-resolving-power x-ray spectrometer for the OMEGA EP Laser (invited)

    Science.gov (United States)

    Nilson, P. M.; Ehrne, F.; Mileham, C.; Mastrosimone, D.; Jungquist, R. K.; Taylor, C.; Stillman, C. R.; Ivancic, S. T.; Boni, R.; Hassett, J.; Lonobile, D. J.; Kidder, R. W.; Shoup, M. J.; Solodov, A. A.; Stoeckl, C.; Theobald, W.; Froula, D. H.; Hill, K. W.; Gao, L.; Bitter, M.; Efthimion, P.; Meyerhofer, D. D.

    2016-11-01

    A high-resolving-power x-ray spectrometer has been developed for the OMEGA EP Laser System based on a spherically bent Si [220] crystal with a radius of curvature of 330 mm and a Spectral Instruments (SI) 800 Series charge-coupled device. The instrument measures time-integrated x-ray emission spectra in the 7.97- to 8.11-keV range, centered on the Cu Kα1 line. To demonstrate the performance of the spectrometer under high-power conditions, Kα1,2 emission spectra were measured from Cu foils irradiated by the OMEGA EP laser with 100-J, 1-ps pulses at focused intensities above 1018 W/cm2. The ultimate goal is to couple the spectrometer to a picosecond x-ray streak camera and measure temperature-equilibration dynamics inside rapidly heated materials. The plan for these ultrafast streaked x-ray spectroscopy studies is discussed.

  13. Chandra Resolves Cosmic X-ray Glow and Finds Mysterious New Sources

    Science.gov (United States)

    2000-01-01

    While taking a giant leap towards solving one of the greatest mysteries of X-ray astronomy, NASA's Chandra X-ray Observatory also may have revealed the most distant objects ever seen in the universe and discovered two puzzling new types of cosmic objects. Not bad for being on the job only five months. Chandra has resolved most of the X-ray background, a pervasive glow of X-rays throughout the universe, first discovered in the early days of space exploration. Before now, scientists have not been able to discern the background's origin, because no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. "This is a major discovery," said Dr. Alan Bunner, Director of NASA's Structure andEvolution of the universe science theme. "Since it was first observed thirty-seven years ago, understanding the source of the X-ray background has been aHoly Grail of X-ray astronomy. Now, it is within reach." The results of the observation will be discussed today at the 195th national meeting of the American Astronomical Society in Atlanta, Georgia. An article describing this work has been submitted to the journal Nature by Dr. Richard Mushotzky, of NASA Goddard Space Flight Center, Greenbelt, Md., Drs. Lennox Cowie and Amy Barger at the University of Hawaii, Honolulu, and Dr. Keith Arnaud of the University of Maryland, College Park. "We are all very excited by this finding," said Mushotzky. "The resolution of most of the hard X-ray background during the first few months of the Chandra mission is a tribute to the power of this observatory and bodes extremely well for its scientific future," Scientists have known about the X-ray glow, called the X-ray background, since the dawn of X-ray astronomy in the early 1960s. They have been unable to discern its origin, however, for no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. The German-led ROSAT mission, now completed, resolved much of the lower

  14. RESOLVED COMPANIONS OF CEPHEIDS: TESTING THE CANDIDATES WITH X-RAY OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Nancy Remage; Pillitteri, Ignazio; Wolk, Scott; Karovska, Margarita; Tingle, Evan [Smithsonian Astrophysical Observatory, MS 4, 60 Garden St., Cambridge, MA 02138 (United States); Guinan, Edward; Engle, Scott [Department of Astronomy and Astrophysics, Villanova University, 800 Lancaster Ave., Villanova, PA 19085 (United States); Bond, Howard E. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Schaefer, Gail H. [The CHARA Array of Georgia State University, Mount Wilson, California 91023 (United States); Mason, Brian D., E-mail: nevans@cfa.harvard.edu, E-mail: heb11@psu.edu, E-mail: schaefer@chara-array.org [US Naval Observatory, 3450 Massachusetts Ave., NW, Washington, DC 20392-5420 (United States)

    2016-04-15

    We have made XMM-Newton observations of 14 Galactic Cepheids that have candidate resolved (≥5″) companion stars based on our earlier HST Wide Field Camera 3 (WFC3) imaging survey. Main-sequence stars that are young enough to be physical companions of Cepheids are expected to be strong X-ray producers in contrast to field stars. XMM-Newton exposures were set to detect essentially all companions hotter than spectral type M0 (corresponding to 0.5 M{sub ⊙}). The large majority of our candidate companions were not detected in X-rays, and hence are not confirmed as young companions. One resolved candidate (S Nor #4) was unambiguously detected, but the Cepheid is a member of a populous cluster. For this reason, it is likely that S Nor #4 is a cluster member rather than a gravitationally bound companion. Two further Cepheids (S Mus and R Cru) have X-ray emission that might be produced by either the Cepheid or the candidate resolved companion. A subsequent Chandra observation of S Mus shows that the X-rays are at the location of the Cepheid/spectroscopic binary. R Cru and also V659 Cen (also X-ray bright) have possible companions closer than 5″ (the limit for this study) which are the likely sources of X-rays. One final X-ray detection (V473 Lyr) has no known optical companion, so the prime suspect is the Cepheid itself. It is a unique Cepheid with a variable amplitude. The 14 stars that we observed with XMM constitute 36% of the 39 Cepheids found to have candidate companions in our HST/WFC3 optical survey. No young probable binary companions were found with separations of ≥5″ or 4000 au.

  15. Resolved Companions of Cepheids: Testing the Candidates with X-Ray Observations

    Science.gov (United States)

    Evans, Nancy Remage; Pillitteri, Ignazio; Wolk, Scott; Karovska, Margarita; Tingle, Evan; Guinan, Edward; Engle, Scott; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.

    2016-04-01

    We have made XMM-Newton observations of 14 Galactic Cepheids that have candidate resolved (≥5″) companion stars based on our earlier HST Wide Field Camera 3 (WFC3) imaging survey. Main-sequence stars that are young enough to be physical companions of Cepheids are expected to be strong X-ray producers in contrast to field stars. XMM-Newton exposures were set to detect essentially all companions hotter than spectral type M0 (corresponding to 0.5 M⊙). The large majority of our candidate companions were not detected in X-rays, and hence are not confirmed as young companions. One resolved candidate (S Nor #4) was unambiguously detected, but the Cepheid is a member of a populous cluster. For this reason, it is likely that S Nor #4 is a cluster member rather than a gravitationally bound companion. Two further Cepheids (S Mus and R Cru) have X-ray emission that might be produced by either the Cepheid or the candidate resolved companion. A subsequent Chandra observation of S Mus shows that the X-rays are at the location of the Cepheid/spectroscopic binary. R Cru and also V659 Cen (also X-ray bright) have possible companions closer than 5″ (the limit for this study) which are the likely sources of X-rays. One final X-ray detection (V473 Lyr) has no known optical companion, so the prime suspect is the Cepheid itself. It is a unique Cepheid with a variable amplitude. The 14 stars that we observed with XMM constitute 36% of the 39 Cepheids found to have candidate companions in our HST/WFC3 optical survey. No young probable binary companions were found with separations of ≥5″ or 4000 au. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).

  16. Study of Multi Total Reflection X-ray Fluorescence Spectrometer

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A total reflection X-ray spectrometer was set up, in which Mo tube was used as excitation source, Zr with the thickness of 100 μm was as filter, and λ/20 glabrous silicon was as reflector, λ/100 glabrous silicon was as sample carrier.

  17. Certification of reference materials by energy-dispersive x-ray fluorescence spectrometry?

    DEFF Research Database (Denmark)

    Christensen, Leif Højslet; Heydorn, Kaj

    1985-01-01

    This paper studies the precision and accuracy that can be achieved using energy-dispersive x-ray fluorescence spectrometry for the determination of total sulphur content in BCR 38 Fly Ash issued by the European Community Bureau of Reference....

  18. Research on U,Np,Pu Excitation Parameter With X-ray Fluorescence Analysis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>X-ray fluorescence analysis is a characteristic analysis technique widely applied in the geology environment and chemical industry. It is also an important quality control analytical method in nuclear

  19. In Situ Mineralogical Analysis of Planetary Materials Using X-Ray Diffraction and X-Ray Fluorescence

    Science.gov (United States)

    Sarrazin, P.; Blake, D.; Vaniman, D.; Chang, Sherwood (Technical Monitor)

    1996-01-01

    Remote observations of Mars have led scientists to believe that its early climate was similar to that of the early Earth, having had abundant liquid water and a dense atmosphere. One of the most fascinating questions of recent times is whether simple bacterial life developed on Mars (as it did on the Earth) during this early element period. Analyses of SNC meteorites have broadened considerably our knowledge of the chemistry of certain types of Martian rocks, underscoring the tantalizing possibility of early hydrothermal systems and even of ancient bacterial life. Detailed analyses of SNC meteorites in Terrestrial laboratories utilize the most sophisticated organic, isotopic and microscopic techniques in existence. Indeed; it is unlikely that the key biogenic indicators used in McKay et al (ibid) could be identified by a remote instrument on the surface of Mars. As a result, it is probable that any robotic search for evidence of an ancient Martian biosphere will have as its focus the identification of key minerals in likely host rocks rather than the direct detection of organic or isotopic biomarkers. Even on a sample return mission, mineralogical screening will be utilized to choose the most likely candidate rocks. X-ray diffraction (XRD) is the only technique that can provide a direct determination of the crystal structures of the phases present within a sample. When many different crystalline phases are present, quantitative analysis is better constrained if used in conjunction with a determination of elemental composition, obtainable by X-ray fluorescence (XRF) using the same X-ray source as for XRD. For planetary surface analysis, a remote instrument combining XRD and XRF could be used for mineralogical characterization of both soils and rocks. We are designing a remote XRD/XRF instrument with this objective in mind. The instrument concept pays specific attention to constraints in sample preparation, weight, volume, power, etc. Based on the geometry of a

  20. ISS Ammonia Leak Detection Through X-Ray Fluorescence

    Science.gov (United States)

    Camp, Jordan; Barthelmy, Scott; Skinner, Gerry

    2013-01-01

    Ammonia leaks are a significant concern for the International Space Station (ISS). The ISS has external transport lines that direct liquid ammonia to radiator panels where the ammonia is cooled and then brought back to thermal control units. These transport lines and radiator panels are subject to stress from micrometeorites and temperature variations, and have developed small leaks. The ISS can accommodate these leaks at their present rate, but if the rate increased by a factor of ten, it could potentially deplete the ammonia supply and impact the proper functioning of the ISS thermal control system, causing a serious safety risk. A proposed ISS astrophysics instrument, the Lobster X-Ray Monitor, can be used to detect and localize ISS ammonia leaks. Based on the optical design of the eye of its namesake crustacean, the Lobster detector gives simultaneously large field of view and good position resolution. The leak detection principle is that the nitrogen in the leaking ammonia will be ionized by X-rays from the Sun, and then emit its own characteristic Xray signal. The Lobster instrument, nominally facing zenith for its astrophysics observations, can be periodically pointed towards the ISS radiator panels and some sections of the transport lines to detect and localize the characteristic X-rays from the ammonia leaks. Another possibility is to use the ISS robot arm to grab the Lobster instrument and scan it across the transport lines and radiator panels. In this case the leak detection can be made more sensitive by including a focused 100-microampere electron beam to stimulate X-ray emission from the leaking nitrogen. Laboratory studies have shown that either approach can be used to locate ammonia leaks at the level of 0.1 kg/day, a threshold rate of concern for the ISS. The Lobster instrument uses two main components: (1) a microchannel plate optic (also known as a Lobster optic) that focuses the X-rays and directs them to the focal plane, and (2) a CCD (charge

  1. Development of low-energy x-ray fluorescence micro-distribution analysis using a laser plasma x-ray source and multilayer optics?

    NARCIS (Netherlands)

    Stuik, R.; Shmaenok, L. A.; Fledderus, H.; Andreev, S. S.; Shamov, E. A.; Zuev, S. Y.; Salashchenko, N. N.; F. Bijkerk,

    1999-01-01

    A new technique is presented for low-energy X-ray fluorescence micro-distribution analysis of low-Z elements at micrometer spatial resolutions. The technique is based on the use of a laser plasma X-ray source and spherically curved multilayer optics. A large collimator is used to focus the light fro

  2. Ultrafast Time-Resolved Hard X-Ray Emission Spectroscopy on a Tabletop

    Science.gov (United States)

    Miaja-Avila, Luis; O'Neil, Galen C.; Joe, Young I.; Alpert, Bradley K.; Damrauer, Niels H.; Doriese, William B.; Fatur, Steven M.; Fowler, Joseph W.; Hilton, Gene C.; Jimenez, Ralph; Reintsema, Carl D.; Schmidt, Daniel R.; Silverman, Kevin L.; Swetz, Daniel S.; Tatsuno, Hideyuki; Ullom, Joel N.

    2016-07-01

    Experimental tools capable of monitoring both atomic and electronic structure on ultrafast (femtosecond to picosecond) time scales are needed for investigating photophysical processes fundamental to light harvesting, photocatalysis, energy and data storage, and optical display technologies. Time-resolved hard x-ray (>3 keV ) spectroscopies have proven valuable for these measurements due to their elemental specificity and sensitivity to geometric and electronic structures. Here, we present the first tabletop apparatus capable of performing time-resolved x-ray emission spectroscopy. The time resolution of the apparatus is better than 6 ps. By combining a compact laser-driven plasma source with a highly efficient array of microcalorimeter x-ray detectors, we are able to observe photoinduced spin changes in an archetypal polypyridyl iron complex [Fe (2 ,2'-bipyridine)3]2 + and accurately measure the lifetime of the quintet spin state. Our results demonstrate that ultrafast hard x-ray emission spectroscopy is no longer confined to large facilities and now can be performed in conventional laboratories with 10 times better time resolution than at synchrotrons. Our results are enabled, in part, by a 100- to 1000-fold increase in x-ray collection efficiency compared to current techniques.

  3. Method for detecting binding events using micro-X-ray fluorescence spectrometry

    Science.gov (United States)

    Warner, Benjamin P.; Havrilla, George J.; Mann, Grace

    2010-12-28

    Method for detecting binding events using micro-X-ray fluorescence spectrometry. Receptors are exposed to at least one potential binder and arrayed on a substrate support. Each member of the array is exposed to X-ray radiation. The magnitude of a detectable X-ray fluorescence signal for at least one element can be used to determine whether a binding event between a binder and a receptor has occurred, and can provide information related to the extent of binding between the binder and receptor.

  4. Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, George J.; Gao, Ning

    2003-06-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. The polycapillary optic will also be used to collect the X-rays from the excitation site. This will effectively screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. This dual-capillary design is essentially a confocal (having the same foci) design, i.e. the detected X-rays are only emitted from the overlap of the two focal spots. This increases spatial resolution and reduce s background. The integration of the X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites.

  5. Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, George J.; Gao, Ning

    2004-06-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. The polycapillary optic will also be used to collect the X-rays from the excitation site. This will effectively screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. This dual-capillary design is essentially a confocal (having the same foci) design, i.e. the detected X-rays are only emitted from the overlap of the two focal spots. This increases spatial resolution and reduces background. The integration of the X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites.

  6. Energy-resolved X-ray detectors: the future of diagnostic imaging

    OpenAIRE

    Pacella D

    2015-01-01

    Danilo Pacella ENEA-Frascati, Rome, Italy Abstract: This paper presents recent progress in the field of X-ray detectors, which could play a role in medical imaging in the near future, with special attention to the new generation of complementary metal-oxide semiconductor (C-MOS) imagers, working in photon counting, that opened the way to the energy-resolved X-ray imaging. A brief description of the detectors used so far in medical imaging (photographic films, imaging plates, flat panel detec...

  7. Time-resolved and position-resolved X-ray spectrometry with a pixelated detector

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, Peter

    2012-12-07

    show a good agreement. Up to now the measurements of impinging spectra with a Timepix detector have been performed in radiation fields with a relatively high fluence. To cope with the requirement of measuring in radiation fields with a low fluence, there had to be changes in the method of analysis compared to those performed formerly. An important improvement in this context was the employment of the Bayesian deconvolution method. The spectra reconstructed with this method were then compared to the results of two different and established detection systems. Firstly, the shape of the deconvolved spectrum was compared to the one measured with a hpGe detector. Secondly, the calculated value of the kerma rate was compared to the one measured with an ionization chamber. This gave an estimate on the correctness of the absolute number of photons. Both comparisons have shown a good agreement and thus I was able to validate that the method delivers precise results. Compared to the formerly used spectrum-stripping method the Bayesian deconvolution turned out to be very stable and reliable. This robustness of the deconvolution method and the development of a pixel-by-pixel energy calibration were the keys towards position-resolved spectrometry. With such a precise energy calibration the energy resolution was enhanced by up to 45%. This improved accuracy in the measurement has been very demanding on the improvements of the simulation of the response matrix needed for deconvolution. Both this enhanced simulation and a pixel-by-pixel calibrated detector opened the possibility of measuring the anode heel effect. Not only the relative angular dependency of the spectrum emitted but also the change in the absolute photon fluence were measured. Furthermore, it is possible to even use small ROIs down to 4x4 pixels to evaluate a spectrum. This was then applied for the spectrometry of small focal spots of a miniature X-ray source used in therapeutics. Furthermore, the robustness and the

  8. Theme Article - Time-Resolved X-Ray Scattering from Coherent Excitations in Solids

    Energy Technology Data Exchange (ETDEWEB)

    Trigo, Mariano; Reis, David (SLAC)

    2010-10-22

    Recent advances in pulsed x-ray sources have opened up new opportunities to study the dynamics of matter directly in the time domain with picosecond to femtosecond resolution. In this article, we present recent results from a variety of ultrafast sources on time-resolved x-ray scattering from elementary excitations in periodic solids. A few representative examples are given on folded acoustic phonons, coherent optical phonons, squeezed phonons, and polaritons excited by femtosecond lasers. Next-generation light sources, such as the x-ray-free electron laser, will lead to improvements in coherence, flux, and pulse duration. These experiments demonstrate potential opportunities for studying matter far from equilibrium on the fastest time scales and shortest distances that will be available in the coming years.

  9. Investigation of X-ray fluorescence computed tomography (XFCT) and K-edge imaging.

    Science.gov (United States)

    Bazalova, Magdalena; Kuang, Yu; Pratx, Guillem; Xing, Lei

    2012-08-01

    This work provides a comprehensive Monte Carlo study of X-ray fluorescence computed tomography (XFCT) and K-edge imaging system, including the system design, the influence of various imaging components, the sensitivity and resolution under various conditions. We modified the widely used EGSnrc/DOSXYZnrc code to simulate XFCT images of two acrylic phantoms loaded with various concentrations of gold nanoparticles and Cisplatin for a number of XFCT geometries. In particular, reconstructed signal as a function of the width of the detector ring, its angular coverage and energy resolution were studied. We found that XFCT imaging sensitivity of the modeled systems consisting of a conventional X-ray tube and a full 2-cm-wide energy-resolving detector ring was 0.061% and 0.042% for gold nanoparticles and Cisplatin, respectively, for a dose of ∼ 10 cGy. Contrast-to-noise ratio (CNR) of XFCT images of the simulated acrylic phantoms was higher than that of transmission K-edge images for contrast concentrations below 0.4%.

  10. X-Ray Diffraction and X-Ray Fluorescent Analyses of Prehistoric Pottery Shards from Ulu Kelantan

    Directory of Open Access Journals (Sweden)

    Zuliskandar Ramli

    2011-01-01

    Full Text Available Problem statement: X-Ray Diffraction (XRD and X-Ray Fluorescent (XRF were used in order to obtain mineralogical and elemental composition of seven pottery shards that have been unearthed during the excavation at Peraling Cave and Cha Cave in Ulu Kelantan, Malaysia. Approach: Peraling Cave and Cha Cave were prehistoric sites dating from 10, 000 BC which were inhabited by Hoabinhian people and then continuously used by people of Neolithic culture around 3000 BC. Results: Mineralogical and elemental analyses were carried out to determine whether the pottery found in the archaeological sites was locally made or trading items. Several clay samples from rivers in Ulu Kelantan such as Perias River, Chai River, Peralon River, Nenggiri River, Betis River and Jenera River were taken to be analysed. Conclusion/Recommendations: Mineralogical and elemental content of the pottery shards showed that the pottery shards did not originate from the Ulu Kelantan area and one of the samples contained clinochlore mineral. Clinochlore forms from the metamorphic and hydrothermal alterations of other iron and magnesium silicate minerals and is usually found in igneus rock and metamorphic rock formation.

  11. Resolving hot spot microstructure using x-ray penumbral imaging (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Bachmann, B., E-mail: bachmann2@llnl.gov; Field, J.; Masters, N.; Pardini, T.; Rygg, J. R.; Benedetti, L. R.; Döppner, T.; Izumi, N.; LePape, S.; Ma, T.; MacPhee, A. G.; Nagel, S.; Patel, P.; Spears, B.; Landen, O. L. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hilsabeck, T.; Reed, C.; Alexander, N.; Forsman, A. [General Atomics, San Diego, California 92186 (United States)

    2016-11-15

    We have developed and fielded x-ray penumbral imaging on the National Ignition Facility in order to enable sub-10 μm resolution imaging of stagnated plasma cores (hot spots) of spherically shock compressed spheres and shell implosion targets. By utilizing circular tungsten and tantalum apertures with diameters ranging from 20 μm to 2 mm, in combination with image plate and gated x-ray detectors as well as imaging magnifications ranging from 4 to 64, we have demonstrated high-resolution imaging of hot spot plasmas at x-ray energies above 5 keV. Here we give an overview of the experimental design criteria involved and demonstrate the most relevant influences on the reconstruction of x-ray penumbral images, as well as mitigation strategies of image degrading effects like over-exposed pixels, artifacts, and photon limited source emission. We describe experimental results showing the advantages of x-ray penumbral imaging over conventional Fraunhofer and photon limited pinhole imaging and showcase how internal hot spot microstructures can be resolved.

  12. PHASE-RESOLVED X-RAY SPECTRA OF MAGNETARS AND THE CORONAL OUTFLOW MODEL

    Energy Technology Data Exchange (ETDEWEB)

    Hascoët, Romain; Beloborodov, Andrei M. [Physics Department and Columbia Astrophysics Laboratory, Columbia University, 538 West 120th Street, New York, NY 10027 (United States); Den Hartog, Peter R., E-mail: hascoet@astro.columbia.edu [Stanford University HEPL/KIPAC, 452 Lomita Mall, Stanford, CA 94305-4085 (United States)

    2014-05-01

    We test a model recently proposed for the persistent hard X-ray emission from magnetars. In the model, hard X-rays are produced by a decelerating electron-positron flow in the closed magnetosphere. The flow decelerates as it radiates its energy away via resonant scattering of soft X-rays, then it reaches the top of the magnetic loop and annihilates there. We test the model against observations of three magnetars: 4U 0142+61, 1RXS J1708-4009, and 1E 1841-045. We find that the model successfully fits the observed phase-resolved spectra. We derive constraints on the angle between the rotational and magnetic axes of the neutron star, the object inclination to the line of sight, and the size of the active twisted region filled with the plasma flow. Using the fit of the hard X-ray component of the magnetar spectrum, we revisit the remaining soft X-ray component. We find that it can be explained by a modified two-temperature blackbody model. The hotter blackbody is consistent with a hot spot covering 1%-10% of the neutron star surface. Such a hot spot is expected at the base of the magnetospheric e {sup ±} outflow, as some particles created in the e {sup ±} discharge flow back and bombard the stellar surface.

  13. Phase-resolved X-ray spectra of magnetars and the coronal outflow model

    CERN Document Server

    Hascoet, R; Hartog, P R den

    2014-01-01

    We test a model recently proposed for the persistent hard X-ray emission from magnetars. In the model, hard X-rays are produced by a decelerating electron-positron flow in the closed magnetosphere. The flow decelerates as it radiates its energy away via resonant scattering of soft X-rays, then it reaches the top of the magnetic loop and annihilates there. We test the model against observations of three magnetars: 4U 0142+61, 1RXS J1708-4009, and 1E 1841-045. We find that the model successfully fits the observed phase-resolved spectra. We derive constraints on the angle between the rotational and magnetic axes of the neutron star, the object inclination to the line of sight, and the size of the active twisted region filled with the plasma flow. Using the fit of the hard X-ray component of the magnetar spectrum, we revisit the remaining soft X-ray component. We find that it can be explained by a modified two-temperature blackbody model. The hotter blackbody is consistent with a hot spot covering 1-10% of the ne...

  14. Versatile, reprogrammable area pixel array detector for time-resolved synchrotron x-ray applications

    Energy Technology Data Exchange (ETDEWEB)

    Gruner, Sol [Cornell Univ., Ithaca, NY (United States)

    2010-05-01

    The final technical report for DOE grant DE-SC0004079 is presented. The goal of the grant was to perform research, development and application of novel imaging x-ray detectors so as to effectively utilize the high intensity and brightness of the national synchrotron radiation facilities to enable previously unfeasible time-resolved x-ray research. The report summarizes the development of the resultant imaging x-ray detectors. Two types of detector platforms were developed: The first is a detector platform (called a Mixed-Mode Pixel Array Detector, or MM-PAD) that can image continuously at over a thousand images per second while maintaining high efficiency for wide dynamic range signals ranging from 1 to hundreds of millions of x-rays per pixel per image. Research on an even higher dynamic range variant is also described. The second detector platform (called the Keck Pixel Array Detector) is capable of acquiring a burst of x-ray images at a rate of millions of images per second.

  15. Resolving hot spot microstructure using x-ray penumbral imaging (invited)

    Science.gov (United States)

    Bachmann, B.; Hilsabeck, T.; Field, J.; Masters, N.; Reed, C.; Pardini, T.; Rygg, J. R.; Alexander, N.; Benedetti, L. R.; Döppner, T.; Forsman, A.; Izumi, N.; LePape, S.; Ma, T.; MacPhee, A. G.; Nagel, S.; Patel, P.; Spears, B.; Landen, O. L.

    2016-11-01

    We have developed and fielded x-ray penumbral imaging on the National Ignition Facility in order to enable sub-10 μm resolution imaging of stagnated plasma cores (hot spots) of spherically shock compressed spheres and shell implosion targets. By utilizing circular tungsten and tantalum apertures with diameters ranging from 20 μm to 2 mm, in combination with image plate and gated x-ray detectors as well as imaging magnifications ranging from 4 to 64, we have demonstrated high-resolution imaging of hot spot plasmas at x-ray energies above 5 keV. Here we give an overview of the experimental design criteria involved and demonstrate the most relevant influences on the reconstruction of x-ray penumbral images, as well as mitigation strategies of image degrading effects like over-exposed pixels, artifacts, and photon limited source emission. We describe experimental results showing the advantages of x-ray penumbral imaging over conventional Fraunhofer and photon limited pinhole imaging and showcase how internal hot spot microstructures can be resolved.

  16. Apparatus and Techniques for Time-resolved Synchrotron X-ray Diffraction using Diamond Anvil Cells

    Science.gov (United States)

    Smith, J.; Sinogeikin, S. V.; Lin, C.; Rod, E.; Bai, L.; Shen, G.

    2015-12-01

    Complementary advances in synchrotron sources, x-ray optics, area detectors, and sample environment control have recently made possible many time-resolved experimental techniques for studying materials at extreme pressure and temperature conditions. The High Pressure Collaborative Access Team (HPCAT) at the Advanced Photon Source has made a sustained effort to assemble a powerful collection of high-pressure apparatus for time-resolved research, and considerable time has been invested in developing techniques for collecting high-quality time-resolved x-ray scattering data. Herein we present key aspects of the synchrotron beamline and ancillary equipment, including source considerations, rapid (de)compression apparatus, high frequency imaging detectors, and software suitable for processing large volumes of data. A number of examples are presented, including fast equation of state measurements, compression rate dependent synthesis of metastable states in silicon and germanium, and ultrahigh compression rates using a piezoelectric driven diamond anvil cell.

  17. Characteristics of X-ray fluorescence of nuclear materials

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seunghoon; Kwak, Sung-Woo; Shin, Jung-Ki; Park, Uk-Rayng; Jung, Heejun [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

    2015-10-15

    LED is a technique of determination of uranium concentration as a continuous X-ray energy beams transmit a uranium liquid sample for safeguards. Compared to K-edge densitometer, due to relatively lower energy (L-edge energy is 17.17 keV) of Uranium L series energy than K-series energy, L-edge densitometer does not require high purity germanium detector with liquid nitride cooling. Therefore, the Ledge densitometer is appropriate for portable equipment for on-site nuclear material inspection and safeguards at facility sites. XRF combined with LED is a technique of finding of nuclear materials from reflected characteristic X-ray photons. In this study, characteristics of XRF of nuclear materials are simulated Monte Carlo method (Geant4) for feasibility of the system for determination of concentration of nuclear species. The analysis method of uranium concentration or minor actinides is applied using combination of linear extrapolation from jump of L-edge of sample and ratio between uranium and minor actinide from XRF measurement. In this study, The XRF ch aracteristics was simulated from Monte Carlo method. The peaks were obtained from nuclear material mixture. The estimated nuclear material concentration is low due to the volume effect of the sample. The correction factor or minimization of the effect is required.

  18. Synchrotron X-ray fluorescence analysis in environmental and earth sciences

    Directory of Open Access Journals (Sweden)

    Adams F.

    2010-12-01

    Full Text Available Compared to other microscopic analytical tools X-ray microscopy techniques have the advantage that the large penetration depth of X-rays in matter allows one to investigate the interior of an object without destructive sample preparation. In combination with X-ray fluorescence tomography, analytical information from inside of a specimen can be obtained. Different X-ray analytical techniques can be used to produce contrast, X-ray absorption, fluorescence, and diffraction, to yield chemical, elemental, and structural information about the sample. Scanning microscopy on the basis of various lens systems in synchrotron radiation sources provides a routine spatial resolution of now about 100 nanometer but in the foreseeable future a 10–20 nanometer spatial resolution can be expected. X-ray absorption spectrometry can also provide chemical (speciation information on the sample. All this makes X-ray microscopy attractive to many fields of science. In this paper the techniques are briefly reviewed and a number of applications in the earth, planetary and cosmos sciences are illustrated with state-of-the art examples, while applications in the environmental sciences and biology are also briefly discussed.

  19. Quantitative analysis results of CE-1 X-ray fluorescence spectrometer ground base experiment

    Institute of Scientific and Technical Information of China (English)

    CUI Xing-Zhu; GAO Min; YANG Jia-Wei; WANG Huan-Yu; ZHANG Cheng-Mo; CHEN Yong; ZHANG Jia-Yu; PENG Wen-Xi; CAO Xue-Lei; LIANG Xiao-Hua; WANG Jin-Zhou

    2008-01-01

    As the nearest celestial body to the earth, the moon has become a hot spot again in astronomy field recently. The element analysis is a much important subject in many lunar projects. Remote X-ray spectrometry plays an important role in the geochemical exploration of the solar bodies. Because of th equasi-vacuum atmosphere on the moon, which has no absorption of X-ray, the X-ray fluorescence analysis is an effective way to determine the elemental abundance of lunar surface. The CE-1 X-ray fluorescence spectrometer (CE-1/XFS) aims to map the major elemental compositions on the lunar surface. This paper describes a method for quantitative analysis of elemental compositions. A series of ground base experiments are done to examine the capability of XFS. The obtained results, which show a reasonable agreement with the certified values at a 30% uncertainty level for major elements, are presented.

  20. Monte Carlo simulation applied in total reflection x-ray fluorescence: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Meira, Luiza L. C.; Inocente, Guilherme F.; Vieira, Leticia D.; Mesa, Joel [Departamento de Fisica e Biofisica - Instituto de Biociencias de Botucatu, Universidade Estadual Paulista Julio de Mesquita Filho (Brazil)

    2013-05-06

    The X-ray Fluorescence (XRF) analysis is a technique for the qualitative and quantitative determination of chemical constituents in a sample. This method is based on detection of the characteristic radiation intensities emitted by the elements of the sample, when properly excited. A variant of this technique is the Total Reflection X-ray Fluorescence (TXRF) that utilizes electromagnetic radiation as excitation source. In total reflection of X-ray, the angle of refraction of the incident beam tends to zero and the refracted beam is tangent to the sample support interface. Thus, there is a minimum angle of incidence at which no refracted beam exists and all incident radiation undergoes total reflection. In this study, we evaluated the influence of the energy variation of the beam of incident x-rays, using the MCNPX code (Monte Carlo NParticle) based on Monte Carlo method.

  1. Characterization of x-ray imaging crystal spectrometer for high-resolution spatially-resolved x-ray Thomson scattering measurements in shock-compressed experiments

    Science.gov (United States)

    Lu, J.; Hill, K. W.; Bitter, M.; Pablant, N. A.; Delgado-Aparicio, L. F.; Efthimion, P. C.; Lee, H. J.; Zastrau, U.

    2017-01-01

    We have proposed, designed and built a dual-channel x-ray imaging crystal spectrometer (XICS) for spectrally- and spatially-resolved x-ray Thomson scattering (XRTS) measurements in the Matter in Extreme Conditions (MEC) end station at the Linac Coherent Light Source (LCLS). This spectrometer employs two spherically-bent germanium (Ge) 220 crystals, which are combined to form a large aperture dispersive element with a spectral bandwidth of 300 eV that enables both the elastic and inelastic x-ray scattering peaks to be simultaneously measured. The apparatus and its characterization are described. A resolving power of 1900 was demonstrated and a spatial resolution of 12 μm was achieved in calibration tests. For XRTS measurements, a narrow-bandwidth (ΔE/Ecarbon plasma produced in shock-compressed samples of different forms of carbon. Preliminary results of the scattering experiments from Pyrolytic Graphite samples that illustrate the utility of the instrument are presented.

  2. Phase-resolved X-ray spectroscopy and spectral energy distribution of the X-ray soft polar RS Caeli

    CERN Document Server

    Traulsen, I; Schwope, A D; Schwarz, R; Walter, F M; Burwitz, V

    2014-01-01

    RS Cae is the third target in our series of XMM-Newton observations of soft X-ray-dominated polars. Our observational campaign aims to better understand and describe the multiwavelength data, the physical properties of the system components, and the short- and long-term behavior of the component fluxes in RS Cae. We employ stellar atmosphere, stratified accretion-column, and widely used X-ray spectral models. We fit the XMM-Newton spectra, model the multiband light curves, and opt for a mostly consistent description of the spectral energy distribution. Results. Our XMM-Newton data of RS Cae are clearly dominated by soft X-ray emission. The X-ray light curves are shaped by emission from the main accretion region, which is visible over the whole orbital cycle, interrupted only by a stream eclipse. The optical light curves are formed by cyclotron and stream emission. The XMM-Newton X-ray spectra comprise a black-body-like and a plasma component at mean temperatures of 36eV and 7keV. The spectral fits give eviden...

  3. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Michael E.; Chapman, David J.; White, Thomas G. [Imperial College London, London (United Kingdom); Drakopoulos, Michael [Diamond Light Source, I12 Joint Engineering, Environmental, Processing (JEEP) Beamline, Didcot, Oxfordshire (United Kingdom); Rack, Alexander [European Synchrotron Radiation Facility, Grenoble (France); Eakins, Daniel E., E-mail: d.eakins@imperial.ac.uk [Imperial College London, London (United Kingdom)

    2016-03-24

    Scintillator performance in time-resolved, hard, indirect detection X-ray studies on the sub-microsecond timescale at synchrotron light sources is reviewed, modelled and examined experimentally. LYSO:Ce is found to be the only commercially available crystal suitable for these experiments. The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits)

  4. Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence

    Energy Technology Data Exchange (ETDEWEB)

    Sutter, John P., E-mail: john.sutter@diamond.ac.uk; Dolbnya, Igor P.; Collins, Stephen P. [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom); Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk; Edwards-Gau, Gregory R.; Kariuki, Benson M. [School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom); Palmer, Benjamin A. [Department of Structural Biology, Weizmann Institute of Science, 234 Herzl St., Rehovot 7610001 (Israel)

    2016-07-27

    Birefringence has been observed in anisotropic materials transmitting linearly polarized X-ray beams tuned close to an absorption edge of a specific element in the material. Synchrotron bending magnets provide X-ray beams of sufficiently high brightness and cross section for spatially resolved measurements of birefringence. The recently developed X-ray Birefringence Imaging (XBI) technique has been successfully applied for the first time using the versatile test beamline B16 at Diamond Light Source. Orientational distributions of the C–Br bonds of brominated “guest” molecules within crystalline “host” tunnel structures (in thiourea or urea inclusion compounds) have been studied using linearly polarized incident X-rays near the Br K-edge. Imaging of domain structures, changes in C–Br bond orientations associated with order-disorder phase transitions, and the effects of dynamic averaging of C–Br bond orientations have been demonstrated. The XBI setup uses a vertically deflecting high-resolution double-crystal monochromator upstream from the sample and a horizontally deflecting single-crystal polarization analyzer downstream, with a Bragg angle as close as possible to 45°. In this way, the ellipticity and rotation angle of the polarization of the beam transmitted through the sample is measured as in polarizing optical microscopy. The theoretical instrumental background calculated from the elliptical polarization of the bending-magnet X-rays, the imperfect polarization discrimination of the analyzer, and the correlation between vertical position and photon energy introduced by the monochromator agrees well with experimental observations. The background is calculated analytically because the region of X-ray phase space selected by this setup is sampled inefficiently by standard methods.

  5. Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, George J.; Gao, Ning

    2002-06-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries and double bent crystals, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. Polycapillaries will also be used to collect the X-rays from the excitation site and screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. A doubly bent crystal used as the focusing optic produces focused monochromatic X-ray excitation, which eliminates the bremsstrahlung background from the X-ray source. The coupling of the doubly bent crystal for monochromatic excitation with a polycapillary for signal collection can effectively eliminate the noise background and radiation background from the specimen. The integration of these X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites.

  6. Simultaneous x-ray fluorescence and K-edge CT imaging with photon-counting detectors

    Science.gov (United States)

    Li, Liang; Li, Ruizhe; Zhang, Siyuan; Chen, Zhiqiang

    2016-10-01

    Rapid development of the X-ray phonon-counting detection technology brings tremendous research and application opportunities. In addition to improvements in conventional X-ray imaging performance such as radiation dose utilization and beam hardening correction, photon-counting detectors allows significantly more efficient X-ray fluorescence (XRF) and K-edge imaging, and promises a great potential of X-ray functional, cellular and molecular imaging. XRF is the characteristic emission of secondary X-ray photons from a material excited by initial X-rays. The phenomenon is widely used for chemical and elemental analysis. K-edge imaging identifies a material based on its chemically-specific absorption discontinuity over X-ray photon energy. In this paper, we try to combine XRF and K-edge signals from the contrast agents (e.g., iodine, gadolinium, gold nanoparticles) to simultaneously realize XFCT and K-edge CT imaging for superior image performance. As a prerequisite for this dual-modality imaging, the accurate energy calibration of multi-energy-bin photon-counting detectors is critically important. With the measured XRF data of different materials, we characterize the energy response function of a CZT detector for energy calibration and spectrum reconstruction, which can effectively improve the energy resolution and decrease the inconsistence of the photon counting detectors. Then, a simultaneous K-edge and X-ray fluorescence CT imaging (SKYFI) experimental setup is designed which includes a cone-beam X-ray tube, two separate photon counting detector arrays, a pin-hole collimator and a rotation stage. With a phantom containing gold nanoparticles the two types of XFCT and K-edge CT datasets are collected simultaneously. Then, XFCT and K-edge CT images are synergistically reconstructed in a same framework. Simulation results are presented and quantitative analyzed and compared with the separate XFCT and K-edge CT results.

  7. Radioisotope-excited x-ray fluorescence analysis and its application to geochemical exploration in Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Kunzendorf, H.

    1973-05-01

    The principles of x-ray fluorescence are briefly described. In particular, two methods of radioisotope x-ray fluorescence analysis are discussed: (a) radioisotope x-ray fluorescence analysis by means of portble apparatus incorporating scintillation or proportional counters and balanced differential x-ray filters, and (b) radioisotope x-ray fluorescence spectrometry by means of Si(Li) or Ge(Li) semiconductor detectors. For a portable radioisotope x-ray fluorescence analyzer calibration curves were established for Cr, Ni, Cu, Zn, Zr, Nb, Mo, La + Ce, and Pb in rock powders, Ti, Zr, and Nb in plane cut rock surfaces, and Zr, Nb, and La + Ce in rock outcrops. Detection limits found from calibration data were 0.3% Cr, 0.06% Ni, 0.14% Cu, 0.14% Zn, 0.04% Zr, 0.07% Nb, 0.03% Mo, 0.02% La + Ce, and 0.1% Pb in rock powders, 0.07% Ti, 0.4% Zr, and 0.1% Nb in cut rock surfaces, and 0.14% Zr, 0.15% Nb, and 0.16% La + Ce in rock outcrops. Values for the accuracy and the precision of these analyses are given. Special investigations include the dependence of the analytical result on the grain size of the sample material and experiments regarding the critical sample weight, Si(Li) and Ge(Li) x-ray spectrometers for the analysis of rock samples were described. Two methods of x-ray spectrum reduction carried out by means of a 32K computer were investigated: simple channel-by-channel integration and leastsquares fitting. Calibration data on rock powders yielded for the Si(Li) x-ray spectrometer (1 mCi/sup 109/Cd for excitation of characteristic x-rays) 25 ppm Rb, 110 ppm Sr, 69 ppm Zr, 206 ppm Nb, and 172 ppm Mo as detection limits for the analysis of rock powders. For plane cut rock surfaces and the Ge(Li) x-ray spectrometer (10 mCi/sup 241/Am for excitation purposel detection limits of 400 ppm Ce and 180 ppm Nb were obtained. The influence of interferences on the analytical result such as overlapping of x- ray peaks, absorption of x-rays in the sample and grain-size effects are

  8. K X-ray fluorescent source for energy-channel calibration of the spectrometer

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new K X-ray fluorescent source for calibrating the X or γ-ray multichannel analyzer spectrometer is introduced. A detailed description of the K fluorescent source device is given. The calibration method used and experimental results obtained are presented. The purity and efficiency of K fluorescence photons from this device are discussed. This new fluorescent source may be used as a substitute for radioactive nuclides for the energy-channel calibration of some MCA spectrometers.

  9. Protein structural dynamics in solution unveiled via 100-ps time-resolved x-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyun Sun; Dashdorj, Naranbaatar; Schotte, Friedrich; Graber, Timothy; Henning, Robert; Anfinruda, Philip (NIH); (UC)

    2010-04-21

    We have developed a time-resolved x-ray scattering diffractometer capable of probing structural dynamics of proteins in solution with 100-ps time resolution. This diffractometer, developed on the ID14B BioCARS (Consortium for Advanced Radiation Sources) beamline at the Advanced Photon Source, records x-ray scattering snapshots over a broad range of q spanning 0.02-2.5 {angstrom}{sup -1}, thereby providing simultaneous coverage of the small-angle x-ray scattering (SAXS) and wide-angle x-ray scattering (WAXS) regions. To demonstrate its capabilities, we have tracked structural changes in myoglobin as it undergoes a photolysis-induced transition from its carbon monoxy form (MbCO) to its deoxy form (Mb). Though the differences between the MbCO and Mb crystal structures are small (rmsd < 0.2 {angstrom}), time-resolved x-ray scattering differences recorded over 8 decades of time from 100 ps to 10 ms are rich in structure, illustrating the sensitivity of this technique. A strong, negative-going feature in the SAXS region appears promptly and corresponds to a sudden > 22 {angstrom}{sup 3} volume expansion of the protein. The ensuing conformational relaxation causes the protein to contract to a volume {approx}2 {angstrom}{sup 3} larger than MbCO within {approx}10 ns. On the timescale for CO escape from the primary docking site, another change in the SAXS/WAXS fingerprint appears, demonstrating sensitivity to the location of the dissociated CO. Global analysis of the SAXS/WAXS patterns recovered time-independent scattering fingerprints for four intermediate states of Mb. These SAXS/WAXS fingerprints provide stringent constraints for putative models of conformational states and structural transitions between them.

  10. 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)

    Khuder, A. [Department of Chemistry, Atomic Energy Commission, P.O. Box 6091, Damascus (Syrian Arab Republic)], E-mail: scientific2@aec.org.sy; Sawan, M.Kh.; Karjou, J. [Department of Chemistry, Atomic Energy Commission, P.O. Box 6091, Damascus (Syrian Arab Republic); Razouk, A.K. [Department of Agriculture, Atomic Energy Commission, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2009-07-15

    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)

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

    Science.gov (United States)

    Khuder, A.; Sawan, M. Kh.; Karjou, J.; Razouk, A. K.

    2009-07-01

    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).

  12. X-ray fluorescence and energy dispersive x-ray diffraction for the quantification of elemental concentrations in breast tissue.

    Science.gov (United States)

    Geraki, K; Farquharson, M J; Bradley, D A

    2004-01-07

    This paper presents improvements on a previously reported method for the measurement of elements in breast tissue specimens (Geraki et al 2002 Phys. Med. Biol. 47 2327-39). A synchrotron-based system was used for the detection of the x-ray fluorescence (XRF) emitted from iron, copper, zinc and potassium in breast tissue specimens, healthy and cancerous. Calibration models resulting from the irradiation of standard aqueous solutions were used for the quantification of the elements. The present developments concentrate on increasing the convergence between the tissue samples and the calibration models, therefore improving accuracy. For this purpose the composition of the samples in terms of adipose and fibrous tissue was evaluated, using an energy dispersive x-ray diffraction (EDXRD) system. The relationships between the attenuation and scatter properties of the two tissue components and water were determined through Monte Carlo simulations. The results from the simulations and the EDXRD measurements allowed the XRF data from each specimen to be corrected according to its composition. The statistical analysis of the elemental concentrations of the different groups of specimens reveals that all four elements are found in elevated levels in the tumour specimens. The increase is less pronounced for iron and copper and most for potassium and zinc. Other observed features include the substantial degree of inhomogeneity of elemental distributions within the volume of the specimens, varying between 4% and 36% of the mean, depending on the element and the type of the sample. The accuracy of the technique, based on the measurement of a standard reference material, proved to be between 3% and 22% depending on the element, which presents only a marginal improvement (1%-3%) compared to the accuracy of the previously reported results. The measurement precision was between 1% and 9% while the calculated uncertainties on the final elemental concentrations ranged between 10% and 16%.

  13. Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystalsa)

    Science.gov (United States)

    Haugh, M. J.; Wu, M.; Jacoby, K. D.; Loisel, G. P.

    2014-11-01

    This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories in Albuquerque, New Mexico. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a double crystal diffractometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.

  14. Resolved Companions of Cepheids: Testing the Candidates with X-Ray Observations

    CERN Document Server

    Evans, Nancy Remage; Wolk, Scott; Karovska, Margarita; Tingle, Evan; Guinan, Edward; Engle, Scott; Bond, Howard E; Schaefer, Gail H; Mason, Brian D

    2016-01-01

    We have made {\\it XMM-Newton\\/} observations of 14 Galactic Cepheids that have candidate resolved ($\\geq$5$\\arcsec$) companion stars based on our earlier {\\it HST\\/} WFC3 imaging survey. Main-sequence stars that are young enough to be physical companions of Cepheids are expected to be strong X-ray producers in contrast to field stars. {\\it XMM-Newton\\/} exposures were set to detect essentially all companions hotter than spectral type M0 (corresponding to 0.5 $ M_\\odot$.) The large majority of our candidate companions were not detected in X-rays, and hence are not confirmed as young companions. One resolved candidate (S~Nor \\#4) was unambiguously detected, but the Cepheid is a member of a populous cluster. For this reason, it is likely that S~Nor \\#4 is a cluster member rather than a gravitationally bound companion. Two further Cepheids (S~Mus and R~Cru) have X-ray emission that might be produced by either the Cepheid or the candidate resolved companion. A subsequent {\\it Chandra} observation of S Mus shows th...

  15. Measuring the X-ray Resolving Power of Bent Potassium Acid Phthalate Diffraction Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Haugh, M. J. [NSTec; Wu, M. [SNL; Jacoby, K. D. [NSTec; Loisel, G. P. [SNL

    2014-11-01

    This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories (SNL) in Albuquerque, NM. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a dual goniometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.

  16. Coherent convergent-beam time-resolved X-ray diffraction

    Science.gov (United States)

    Spence, John C. H.; Zatsepin, Nadia A.; Li, Chufeng

    2014-01-01

    The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. PMID:24914153

  17. A novel setup for time-resolved X-ray diffraction on gas gun experiments

    Science.gov (United States)

    Zucchini, Frédéric; Chauvin, Camille; Loyen, Arnaud; Combes, Philippe; Petit, Jacques; Bland, Simon

    2017-01-01

    Polymorphic phase transitions in metals have been investigated for a long time under dynamic loadings through usual dynamic compression diagnostics such as velocity and temperature measurements. Such measurements were valuable for revealing the key role of kinetic effects in most phase transition mechanisms. However, the information extracted was mostly macroscopic. Obtaining direct insight about the crystallographic structure under dynamic loadings is critical for understanding mechanisms governing shock-induced structural changes. For example, in order to evidence a mixture phase or to determine the time scale of a transition, structural information may be extremely valuable. Over the last 20 years a significant number of X-ray diffraction experiments were carried under dynamic loading, either using laboratory X-ray sources or synchrotron radiation. We are developing a novel experimental setup based on a compact High Pulsed Power generator capable of producing intense X radiation through an X-pinch X-ray source. This source is specifically designed for time-resolved X-ray diffraction in Bragg geometry on gas gun experiments. Promising preliminary diffraction data obtained under static conditions are presented.

  18. Thermal transport in thin films measured by time-resolved, grazing incidence x-ray diffraction.

    Energy Technology Data Exchange (ETDEWEB)

    Walko, D. A.; Sheu, Y.-M.; Trigo, M.; Reis, D. A. (X-Ray Science Division); (Univ. of Michigan,); (SLAC National Accelerator Lab.); (Stanford Univ.)

    2011-01-01

    We use depth- and time-resolved x-ray diffraction to study thermal transport across single crystal Bi films grown on sapphire in order to determine the thermal conductivity of the film and the Kapitza conductance of the interface. Ultrafast Ti:sapphire laser pulses were used to heat the films; x-ray diffraction then measured the film's lattice expansion. Use of grazing incidence diffraction geometry provided depth sensitivity, as the x-ray angle of incidence was varied near the critical angle. The shift of the film's Bragg peak position with time was used to determine the film temperature averaged over an x-ray penetration depth that could be selected by choice of the angle of incidence. For films that were thick compared to the laser penetration depth, we observed a large temperature gradient at early times. In this case, measurements with the incident angle near or well above the critical angle were more sensitive to the film conductivity or Kapitza conductance, respectively. For thinner films, however, cooling was dominated by the Kapitza conductance at all accessible time scales.

  19. Coherent convergent-beam time-resolved X-ray diffraction.

    Science.gov (United States)

    Spence, John C H; Zatsepin, Nadia A; Li, Chufeng

    2014-07-17

    The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  20. Multi-angular regolith effects on planetary soft X-ray fluorescence spectroscopy

    Science.gov (United States)

    Näränen, J.; Parviainen, H.; Carpenter, J.; Muinonen, K.

    2009-04-01

    Fluorescent X-rays from the surfaces of airless planetary bodies in the inner solar system have been measured by instruments on several spacecraft. MESSENGER carries an X-ray spectrometer (XRS) on-board and has already attempted to obtain fluorescent X-rays from the Hermean surface. BepiColombo will later on carry an X-ray telescope (MIXS-T) along with a more conventional collimating detector (MIXS-C) to the Hermean orbit, supported by a next-generation X-ray solar monitor (SIXS). These instruments will provide unprecedented knowledge about the geochemical properties of the Hermean regolith. X-ray emission from planetary surfaces follows photoionisation by incident solar X-rays and charged particles and reveals information about the elemental composition of the surface. Analyses of X-ray spectra, obtained by orbiting spacecraft, use both the relative intensities of elemental emission lines (e.g., Ca/Si, Fe/Si) and absolute abundancies of the elements to determine the geochemistry of the target body. Historically, the analysis of X-ray spectra has largely assumed that surfaces can be considered as homogeneous plane-parallel media. It has been shown, however, that fluorescent line intensities are affected by the physical properties of the target surface (e.g., surface roughness of the regolith) as a function of the viewing and illumination geometry of observations in a way that cannot be explained by the traditional models. We describe experimental investigations where we simulated the effects of regolith properties on the fluorescent lines measured by an orbiting instrument, with a large variety of illumination and viewing angles. The planetary regolith analogue used in these experiments was a terrestrial, olivine rich basalt, which has been used by previous authors as an analogue to the lunar maria. The basalt samples were ground to powder and sieved to discriminate particles in the ranges, pellets. The separation of particles with different sizes allows some

  1. Determination of plutonium in nitric acid solutions using energy dispersive L X-ray fluorescence with a low power X-ray generator

    Energy Technology Data Exchange (ETDEWEB)

    Py, J. [Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, 16 route de Gray, F-25030 Besançon (France); Commissariat à l’Énergie Atomique, Centre de Valduc, F-21120 Is-sur-Tille (France); Groetz, J.-E., E-mail: jegroetz@univ-fcomte.fr [Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, 16 route de Gray, F-25030 Besançon (France); Hubinois, J.-C.; Cardona, D. [Commissariat à l’Énergie Atomique, Centre de Valduc, F-21120 Is-sur-Tille (France)

    2015-04-21

    This work presents the development of an in-line energy dispersive L X-ray fluorescence spectrometer set-up, with a low power X-ray generator and a secondary target, for the determination of plutonium concentration in nitric acid solutions. The intensity of the L X-rays from the internal conversion and gamma rays emitted by the daughter nuclei from plutonium is minimized and corrected, in order to eliminate the interferences with the L X-ray fluorescence spectrum. The matrix effects are then corrected by the Compton peak method. A calibration plot for plutonium solutions within the range 0.1–20 g L{sup −1} is given.

  2. Elemental mapping in a contemporary miniature by full-field X-ray fluorescence imaging with gaseous detector vs. scanning X-ray fluorescence imaging with polycapillary optics

    Science.gov (United States)

    Silva, A. L. M.; Cirino, S.; Carvalho, M. L.; Manso, M.; Pessanha, S.; Azevedo, C. D. R.; Carramate, L. F. N. D.; Santos, J. P.; Guerra, M.; Veloso, J. F. C. A.

    2017-03-01

    Energy dispersive X-ray imaging can be used in several research fields and industrial applications. Elemental mapping through energy dispersive X-ray imaging technique has become a promising method to obtain positional distribution of specific elements in a non-destructive way. To obtain the elemental distribution of a sample it is necessary to use instruments capable of providing a precise positioning together with a good energy resolution. Polycapillary beams together with silicon drift chamber detectors are used in several commercial systems and are considered state-of-the-art spectrometers, however they are usually very costly. A new concept of large energy dispersive X-ray imaging systems based on gaseous radiation detectors emerged in the last years enabling a promising 2D elemental detection at a very reduced price. The main goal of this work is to analyze a contemporary Indian miniature with both X-ray fluorescence imaging systems, the one based on a gaseous detector 2D-THCOBRA and the state-of-the-art spectrometer M4 Tornado, from Bruker. The performance of both systems is compared and evaluated in the context of the sample's analysis.

  3. Analysis of archaeological ceramics by total-reflection X-ray fluorescence: Quantitative approaches

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Ruiz, R. [Servicio Interdepartamental de Investigacion, Facultad de Ciencias, Universidad Autonoma de Madrid, Modulo C-9, Laboratorio de TXRF, Crta. Colmenar, Km 15, Cantoblanco, E-28049, Madrid (Spain)], E-mail: ramon.fernandez@uam.es; Garcia-Heras, M. [Grupo de Arqueometria de Vidrios y Materiales Ceramicos, Instituto de Historia, Centro de Ciencias Humanas y Sociales, CSIC, C/ Albasanz, 26-28, 28037 Madrid (Spain)

    2008-09-15

    This paper reports the quantitative methodologies developed for the compositional characterization of archaeological ceramics by total-reflection X-ray fluorescence at two levels. A first quantitative level which comprises an acid leaching procedure, and a second selective level, which seeks to increase the number of detectable elements by eliminating the iron present in the acid leaching procedure. Total-reflection X-ray fluorescence spectrometry has been compared, at a quantitative level, with Instrumental Neutron Activation Analysis in order to test its applicability to the study of this kind of materials. The combination of a solid chemical homogenization procedure previously reported with the quantitative methodologies here presented allows the total-reflection X-ray fluorescence to analyze 29 elements with acceptable analytical recoveries and accuracies.

  4. Development of a total reflection X-ray fluorescence spectrometer for ultra-trace element analysis

    Indian Academy of Sciences (India)

    M K Tiwari; B Gowrishankar; V K Raghuvanshi; R V Nandedkar; K J S Sawhney

    2002-10-01

    A simple and fairly inexpensive total reflection X-ray fluorescence (TXRF) spectrometer has been designed, constructed and realized. The spectrometer is capable of ultra-trace multielement analysis as well as performs surface characterization of thin films. The TXRF setup comprises of an X-ray generator, a slitcollimator arrangement, a monochromator/cutoff-stage, a sample reflector stage and an X-ray detection system. The glancing angle of incidence on the two reflectors is implemented using a sine-bar mechanism that enables precise angle adjustments. An energy dispersive detector and a GM counter are employed for measuring respectively the fluorescence intensities and the direct X-ray beam intensity. A Cu-target X-ray generator with its line focus window is used as an excitation source. The spectrometer is quite portable with its compact design and use of a peltier cooled solid state detector for energy dispersive detection. Alignment and characterization of the TXRF system has been performed and the minimum detection limits for various elements have been determined to be in the range of 100 pg to 5 ng even at low X-ray generator powers of 30 kV, 5 mA. The capability of the TXRF system developed for thin film characterization is also demonstrated.

  5. Calculating the X-Ray Fluorescence from the Planet Mercury Due to High-Energy Electrons

    Science.gov (United States)

    Burbine, T. H.; Trombka, J. I.; Bergstrom, P. M., Jr.; Christon, S. P.

    2005-01-01

    The least-studied terrestrial planet is Mercury due to its proximity to the Sun, which makes telescopic observations and spacecraft encounters difficult. Our lack of knowledge about Mercury should change in the near future due to the recent launching of MESSENGER, a Mercury orbiter. Another mission (BepiColombo) is currently being planned. The x-ray spectrometer on MESSENGER (and planned for BepiColombo) can characterize the elemental composition of a planetary surface by measuring emitted fluorescent x-rays. If electrons are ejected from an atom s inner shell by interaction with energetic particles such as photons, electrons, or ions, electrons from an outer shell can transfer to the inner shell. Characteristic x-rays are then emitted with energies that are the difference between the binding energy of the ion in its excited state and that of the ion in its ground state. Because each element has a unique set of energy levels, each element emits x-rays at a unique set of energies. Electrons and ions usually do not have the needed flux at high energies to cause significant x-ray fluorescence on most planetary bodies. This is not the case for Mercury where high-energy particles were detected during the Mariner 10 flybys. Mercury has an intrinsic magnetic field that deflects the solar wind, resulting in a bow shock in the solar wind and a magnetospheric cavity. Electrons and ions accelerated in the magnetosphere tend to follow its magnetic field lines and can impact the surface on Mercury s dark side Modeling has been done to determine if x-ray fluorescence resulting from the impact of high-energy electrons accelerated in Mercury's magnetosphere can be detected by MESSENGER. Our goal is to understand how much bulk chemical information can be obtained from x-ray fluorescence measurements on the dark side of Mercury.

  6. Time-resolved X-ray transmission microscopy on magnetic microstructures; Zeitaufloesende Roentgentransmissionsmikroskopie an magnetischen Mikrostrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Puzic, Aleksandar

    2007-10-23

    Three excitation schemes were designed for stroboscopic imaging of magnetization dynamics with time-resolved magnetic transmission X-ray microscopy (TR-MTXM). These techniques were implemented into two types of X-ray microscopes, namely the imaging transmission X-ray microscope (ITXM) and the scanning transmission X-ray microscope (STXM), both installed at the electron storage ring of the Advanced Light Source in Berkeley, USA. Circular diffraction gratings (Fresnel zone plates) used in both microscopes as focusing and imaging elements presently allow for lateral resolution down to 30 nm. Magnetic imaging is performed by using the X-ray magnetic circular dichroism (XMCD) as element specific contrast mechanism. The developed methods have been successfully applied to the experimental investigation of magnetization dynamics in ferromagnetic microstructures. A temporal resolution well below 100 ps was achieved. A conventional pump-probe technique was implemented first. The dynamic response of the magnetization excited by a broadband pulsed magnetic field was imaged spatially resolved using focused X-ray flashes. As a complementary method, the spatially resolved ferromagnetic resonance (SR-FMR) technique was developed for experimental study of magnetization dynamics in the frequency domain. As a third excitation mode, the burst excitation was implemented. The performance and efficiency of the developed methods have been demonstrated by imaging the local magnetization dynamics in laterally patterned ferromagnetic thin-film elements and three-layer stacks. The existence of multiple eigenmodes in the excitation spectra of ferromagnetic microstructures has been verified by using the pump-probe technique. Magnetostatic spin waves were selectively excited and detected with a time resolution of 50 ps using the SR-FMR technique. Thorough analysis of 20 in most cases independently prepared samples has verified that vortices which exhibit a low-amplitude switching of their core

  7. Characterization of atmospheric aerosols using Synchroton radiation total reflection X-ray fluorescence and Fe K-edge total reflection X-ray fluorescence-X-ray absorption near-edge structure

    Energy Technology Data Exchange (ETDEWEB)

    Fittschen, U.E.A. [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)], E-mail: ursula.fittschen@chemie.uni-hamburg.de; Meirer, F. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: fmeirer@ati.ac.at; Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: streli@ati.ac.at; Wobrauschek, P. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Wien (Austria)], E-mail: wobi@ati.ac.at; Thiele, J. [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)], E-mail: Julian.Thiele@gmx.de; Falkenberg, G. [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603 Hamburg (Germany)], E-mail: falkenbe@mail.desy.de; Pepponi, G. [ITC-irst, Via Sommarive 18, 38050 Povo (Trento) (Italy)], E-mail: pepponi@itc.it

    2008-12-15

    In this study a new procedure using Synchrotron total reflection X-ray fluorescence (SR-TXRF) to characterize elemental amounts in atmospheric aerosols down to particle sizes of 0.015 um is presented. The procedure was thoroughly evaluated regarding bounce off effects and blank values. Additionally the potential of total reflection X-ray fluorescence-X-ray absorption near edge structure (SR-TXRF-XANES) for speciation of FeII/III down to amounts of 34 pg in aerosols which were collected for 1 h is shown. The aerosols were collected in the city of Hamburg with a low pressure Berner impactor on Si carriers covered with silicone over time periods of 60 and 20 min each. The particles were collected in four and ten size fractions of 10.0-8.0 {mu}m, 8.0-2.0 {mu}m, 2.0-0.13 {mu}m 0.13-0.015 {mu}m (aerodynamic particle size) and 15-30 nm, 30-60 nm, 60-130 nm, 130-250 nm, 250-500 nm, 0.5-1 {mu}m, 1-2 {mu}m, 2-4 {mu}m, 4-8 {mu}m, 8-16 {mu}m. Prior to the sampling 'bounce off' effects on Silicone and Vaseline coated Si carriers were studied with total reflection X-ray fluorescence. According to the results silicone coated carriers were chosen for the analysis. Additionally, blank levels originating from the sampling device and the calibration procedure were studied. Blank levels of Fe corresponded to 1-10% of Fe in the aerosol samples. Blank levels stemming from the internal standard were found to be negligible. The results from the Synchroton radiation total reflection X-ray fluorescence analysis of the aerosols showed that 20 min of sampling time gave still enough sample material for elemental determination of most elements. For the determination of the oxidation state of Fe in the aerosols different Fe salts were prepared as a reference from suspensions in isopropanol. The results from the Fe K-edge Synchroton radiation total reflection X-ray fluorescence-X-ray absorption near-edge structure analysis of the aerosol samples showed that mainly Fe(III) was present in

  8. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Nicoul, Matthieu

    2010-09-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

  9. Improving accuracy and capabilities of X-ray fluorescence method using intensity ratios

    Science.gov (United States)

    Garmay, Andrey V.; Oskolok, Kirill V.

    2017-04-01

    An X-ray fluorescence analysis algorithm is proposed which is based on a use of ratios of X-ray fluorescence lines intensities. Such an analytical signal is more stable and leads to improved accuracy. Novel calibration equations are proposed which are suitable for analysis in a broad range of matrix compositions. To apply the algorithm to analysis of samples containing significant amount of undetectable elements a use of a dependence of a Rayleigh-to-Compton intensity ratio on a total content of these elements is suggested. The technique's validity is shown by analysis of standard steel samples, model metal oxides mixture and iron ore samples.

  10. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS METHOD DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2007-08-08

    The x-ray fluorescence laboratory (XRF) in the Analytical Development Directorate (ADD) of the Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop an XRF analytical method that provides rapid turnaround time (<8 hours), while providing sufficient accuracy and precision to determine variations in waste.

  11. Dense Heavy Metal Aerosol Monitoring by Direct X-Ray Fluorescence

    Science.gov (United States)

    1989-06-01

    TECHNICAL REPORT BRL-TR-3003 BRL 0 sDENSE HEAVY METAL AEROSOL MONITORING BY DIRECT X-RAY FLUORESCENCE I GEORGE M. THOMSON flgDTIC ELF% CTE b JUN 16...21005-5066 /F 6261A jIN8 1001I 11. TITLE (-’mi- Sawt Cauif&aan)II DENSE HEAVY METAL AEROSOL MONITORMN BY DIRECT X-RAY FLUORESCENCE 12. PERSONAL AUTHOR(S...Before proceeding, a definition of the term "dense, heavy - metal aerosol" is in order. For present purposes, it is an aerosol in which the suspended

  12. Improving accuracy and capabilities of X-ray fluorescence method using intensity ratios

    Energy Technology Data Exchange (ETDEWEB)

    Garmay, Andrey V., E-mail: andrew-garmay@yandex.ru; Oskolok, Kirill V.

    2017-04-15

    An X-ray fluorescence analysis algorithm is proposed which is based on a use of ratios of X-ray fluorescence lines intensities. Such an analytical signal is more stable and leads to improved accuracy. Novel calibration equations are proposed which are suitable for analysis in a broad range of matrix compositions. To apply the algorithm to analysis of samples containing significant amount of undetectable elements a use of a dependence of a Rayleigh-to-Compton intensity ratio on a total content of these elements is suggested. The technique's validity is shown by analysis of standard steel samples, model metal oxides mixture and iron ore samples.

  13. Femtosecond time-resolved X-ray absorption spectroscopy of liquid using a hard X-ray free electron laser in a dual-beam dispersive detection method.

    Science.gov (United States)

    Obara, Yuki; Katayama, Tetsuo; Ogi, Yoshihiro; Suzuki, Takayuki; Kurahashi, Naoya; Karashima, Shutaro; Chiba, Yuhei; Isokawa, Yusuke; Togashi, Tadashi; Inubushi, Yuichi; Yabashi, Makina; Suzuki, Toshinori; Misawa, Kazuhiko

    2014-01-13

    We present femtosecond time-resolved X-ray absorption spectroscopy of aqueous solution using a hard x-ray free electron laser (SACLA) and a synchronized Ti:sapphire laser. The instrumental response time is 200 fs, and the repetition rate of measurement is 10 Hz. A cylindrical liquid beam 100 μm in diameter of aqueous ammonium iron(III) oxalate solution is photoexcited at 400 nm, and the transient X-ray absorption spectra are measured in the K-edge region of iron, 7.10 - 7.26 keV, using a dual X-ray beam dispersive detection method. Each of the dual beams has the pulse energy of 1.4 μJ, and pump-induced absorbance change on the order of 10(-3) is successfully detected. The photoexcited iron complex exhibits a red shifted iron K-edge with the appearance time constant of 260 fs. The X-ray absorption difference spectra, with and without the pump pulses, are independent of time delay after 1.5 ps up to 100 ps, indicating that the photoexcited species is long-lived.

  14. Time-resolved X-ray PIV measurements of hemodynamic information of real pulsatile blood flows

    Science.gov (United States)

    Park, Hanwook; Yeom, Eunseop; Lee, Sang Joon

    2015-11-01

    X-ray imaging technique has been used to visualize various bio-fluid flow phenomena as a nondestructive manner. To obtain hemodynamic information related with circulatory vascular diseases, a time-resolved X-ray PIV technique with high temporal resolution was developed. In this study, to embody actual pulsatile blood flows in a circular conduit without changes in hemorheological properties, a bypass loop is established by connecting a microtube between the jugular vein and femoral artery of a rat. Biocompatible CO2 microbubbles are used as tracer particles. After mixing with whole blood, CO2 microbubbles are injected into the bypass loop. Particle images of the pulsatile blood flows in the bypass loop are consecutively captured by the time-resolved X-ray PIV system. The velocity field information are obtained with varying flow rate and pulsataility. To verify the feasibility of the use of CO2 microbubbles under in vivo conditions, the effects of the surrounding-tissues are also investigated, because these effects are crucial for deteriorating the image contrast of CO2 microbubbles. Therefore, the velocity information of blood flows in the abdominal aorta are obtained to demonstrate the visibility and usefulness of CO2 microbubbles under ex vivo conditions. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2008-0061991).

  15. Protein structural dynamics revealed by time-resolved X-ray solution scattering.

    Science.gov (United States)

    Kim, Jong Goo; Kim, Tae Wu; Kim, Jeongho; Ihee, Hyotcherl

    2015-08-18

    One of the most important questions in biological science is how a protein functions. When a protein performs its function, it undergoes regulated structural transitions. In this regard, to better understand the underlying principle of a protein function, it is desirable to monitor the dynamic evolution of the protein structure in real time. To probe fast and subtle motions of a protein in physiological conditions demands an experimental tool that is not only equipped with superb spatiotemporal resolution but also applicable to samples in solution phase. Time-resolved X-ray solution scattering (TRXSS), discussed in this Account, fits all of those requirements needed for probing the movements of proteins in aqueous solution. The technique utilizes a pump-probe scheme employing an optical pump pulse to initiate photoreactions of proteins and an X-ray probe pulse to monitor ensuing structural changes. The technical advances in ultrafast lasers and X-ray sources allow us to achieve superb temporal resolution down to femtoseconds. Because X-rays scatter off all atomic pairs in a protein, an X-ray scattering pattern provides information on the global structure of the protein with subangstrom spatial resolution. Importantly, TRXSS is readily applicable to aqueous solution samples of proteins with the aid of theoretical models and therefore is well suited for investigating structural dynamics of protein transitions in physiological conditions. In this Account, we demonstrate that TRXSS can be used to probe real-time structural dynamics of proteins in solution ranging from subtle helix movement to global conformational change. Specifically, we discuss the photoreactions of photoactive yellow protein (PYP) and homodimeric hemoglobin (HbI). For PYP, we revealed the kinetics of structural transitions among four transient intermediates comprising a photocycle and, by applying structural analysis based on ab initio shape reconstruction, showed that the signaling of PYP involves

  16. Ultrafast laser-induced melting and ablation studied by time-resolved diffuse X-ray scattering

    Directory of Open Access Journals (Sweden)

    Meyer zu Heringdorf F.

    2013-03-01

    Full Text Available Time-resolved diffuse X-ray scattering with 50 fs, 9.5 keV X-ray pulses from the Linear Coherent Light Source was used to study the structural dynamics in materials undergoing rapid melting and ablation after fs laser excitation.

  17. Watching proteins function with time-resolved x-ray crystallography

    Science.gov (United States)

    Šrajer, Vukica; Schmidt, Marius

    2017-09-01

    Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115-54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201-41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651-9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237-51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242-6, Barends et al 2015 Science 350 445-50, Pande et al 2016 Science 352 725-9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline

  18. Watching proteins function with time-resolved x-ray crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Šrajer, Vukica; Schmidt, Marius

    2017-08-22

    Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We

  19. Detection limits for actinides in a monochromatic, wavelength-dispersive x-ray fluorescence instrument

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Michael L [Los Alamos National Laboratory; Havrilla, George J [Los Alamos National Laboratory

    2009-01-01

    Recent developments in x-ray optics have made it possible to examine the L x-rays of actinides using doubly-curved crystals in a bench-top device. A doubly-curved crystal (DCC) acts as a focusing monochromatic filter for polychromatic x-rays. A Monochromatic, Wavelength-Dispersive X-Ray Fluorescence (MWDXRF) instrument that uses DCCs to measure Cm and Pu in reprocessing plant liquors was proposed in 2007 by the authors at Los Alamos National Laboratory. A prototype design of this MWDXRF instrument was developed in collaboration with X-ray Optical Systems Inc. (XOS), of East Greenbush, New York. In the MWDXRF instrument, x-rays from a Rhodium-anode x-ray tube are passed through a primary DCC to produce a monochromatic beam of 20.2-keV photons. This beam is focused on a specimen that may contain actinides. The 20.2-keV interrogating beam is just above the L3 edge of Californium; each actinide (with Z = 90 to 98) present in the specimen emits characteristic L x-rays as the result of L3-shell vacancies. In the LANL-XOS prototype MWDXRf, these x-rays enter a secondary DCC optic that preferentially passes 14.961-keV photons, corresponding to the L-alpha-1 x-ray peak of Curium. In the present stage of experimentation, Curium-bearing specimens have not been analyzed with the prototype MWDXRF instrument. Surrogate materials for Curium include Rubidium, which has a K-beta-l x-ray at 14.961 keV, and Yttrium, which has a K-alpha-1 x-ray at 14.958 keV. In this paper, the lower limit of detection for Curium in the LANL-XOS prototype MWDXRF instrument is estimated. The basis for this estimate is described, including a description of computational models and benchmarking techniques used. Detection limits for other actinides are considered, as well as future safeguards applications for MWDXRF instrumentation.

  20. Nanometer-resolution depth-resolved measurement of florescence-yield soft x-ray absorption spectroscopy for FeCo thin film

    Science.gov (United States)

    Sakamaki, M.; Amemiya, K.

    2017-08-01

    We develop a fluorescence-yield depth-resolved soft x-ray absorption spectroscopy (XAS) technique, which is based on the principle that the probing depth is changed by the emission angle of the fluorescence soft x rays. Compared with the electron-yield depth-resolved XAS technique, which has been established in this decade, we can observe wider range in-depth XAS distribution up to several tens of nm. Applying this technique to a 30 ML (˜4.3 nm) FeCo thin film, we observe Fe L-edge XAS spectra at the probing depth of 0.3-6 nm and find that the film has 22 ML (˜3.1 nm) surface oxide layer while its inner layer shows metallic state. We thus successfully obtain nanometer-resolution depth-resolved XAS spectra and further expect that operando measurement under the electric and/or magnetic fields is possible.

  1. Three dimensional subsurface elemental identification of minerals using confocal micro-X-ray fluorescence and micro-X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cordes, Nikolaus L., E-mail: ncordes@lanl.gov [Polymers and Coatings Group, Material Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Seshadri, Srivatsan, E-mail: srivatsan.seshadri@zeiss.com [Carl Zeiss X-ray Microscopy, Inc., Pleasanton, CA 94588 (United States); Havrilla, George J. [Chemical Diagnostics and Engineering, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Yuan, Xiaoli [Julius Kruttschnitt Mineral Research Centre, University of Queensland, Indooroopilly, Brisbane, QLD 4068 (Australia); Feser, Michael [Carl Zeiss X-ray Microscopy, Inc., Pleasanton, CA 94588 (United States); Patterson, Brian M. [Polymers and Coatings Group, Material Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2015-01-01

    Current non-destructive elemental characterization methods, such as scanning electron microscopy-based energy dispersive spectroscopy (SEM–EDS) and micro-X-ray fluorescence spectroscopy (MXRF), are limited to either elemental identification at the surface (SEM–EDS) or suffer from an inability to discriminate between surface or depth information (MXRF). Thus, a non-destructive elemental characterization of individual embedded particles beneath the surface is impossible with either of these techniques. This limitation can be overcome by using laboratory-based 3D confocal micro-X-ray fluorescence spectroscopy (confocal MXRF). This technique utilizes focusing optics on the X-ray source and detector which allows for spatial discrimination in all three dimensions. However, the voxel-by-voxel serial acquisition of a 3D elemental scan can be very time-intensive (~ 1 to 4 weeks) if it is necessary to locate individual embedded particles of interest. As an example, if each point takes a 5 s measurement time, a small volume of 50 × 50 × 50 pixels leads to an acquisition time of approximately 174 h, not including sample stage movement time. Initially screening the samples for particles of interest using micro-X-ray computed tomography (micro-CT) can significantly reduce the time required to spatially locate these particles. Once located, these individual particles can be elementally characterized with confocal MXRF. Herein, we report the elemental identification of high atomic number surface and subsurface particles embedded in a mineralogical matrix by coupling micro-CT and confocal MXRF. Synergistically, these two X-ray based techniques first rapidly locate and then elementally identify individual subsurface particles. - Highlights: • Coupling of confocal X-ray fluorescence spectroscopy and X-ray computed tomography • Qualitative elemental identification of surface and subsurface mineral particles • Non-destructive particle size measurements • Utilization of

  2. Time-, Frequency-, and Wavevector-Resolved X-Ray Diffraction from Single Molecules

    CERN Document Server

    Bennett, Kochise; Zhang, Yu; Dorfman, Konstantin E; Mukamel, Shaul

    2014-01-01

    Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broad-band X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and ...

  3. Time resolved energy dispersive X-ray diagnostic for the TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, J.; Amaro, P.; Amorim, P.; Varandas, C.A.F. [Associacao EURATOM/IST, Centro de Fusao Nuclear, Instituto Superior Tecnico, Lisbon (Portugal); Duval, B. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1996-10-01

    A time resolved energy dispersive X-ray diagnostic is being developed for the TCV tokamak (CRPP - Lausanne) to measure the evolution of the plasma impurities, runaway electrons and electron temperature. A liquid nitrogen cooled Ge diode detects the X-ray photons which are processed by a spectroscopic amplifier and a locally developed interface amplifier and timing generator (IATG) unit. The energy spectrum is obtained using a fast digitiser and a software histogramming algorithm. These electronics components have been optimised to improve the data throughput to match high flux 2 seconds time duration of a TCV plasma pulse. This paper describes the diagnostic hardware with particular emphasis on the IATG unit. (author) 5 figs., 4 refs.

  4. Depth-resolved soft x-ray photoelectron emission microscopy in nanostructures via standing-wave excited photoemission

    Energy Technology Data Exchange (ETDEWEB)

    Kronast, F.; Ovsyannikov, R.; Kaiser, A.; Wiemann, C.; Yang, S.-H.; Locatelli, A.; Burgler, D.E.; Schreiber, R.; Salmassi, F.; Fischer, P.; Durr, H.A.; Schneider, C.M.; Eberhardt, W.; Fadley, C.S.

    2008-11-24

    We present an extension of conventional laterally resolved soft x-ray photoelectron emission microscopy. A depth resolution along the surface normal down to a few {angstrom} can be achieved by setting up standing x-ray wave fields in a multilayer substrate. The sample is an Ag/Co/Au trilayer, whose first layer has a wedge profile, grown on a Si/MoSi2 multilayer mirror. Tuning the incident x-ray to the mirror Bragg angle we set up standing x-ray wave fields. We demonstrate the resulting depth resolution by imaging the standing wave fields as they move through the trilayer wedge structure.

  5. Picosecond time-resolved laser pump/X-ray probe experiments using a gated single-photon-counting area detector

    DEFF Research Database (Denmark)

    Ejdrup, T.; Lemke, H.T.; Haldrup, Martin Kristoffer

    2009-01-01

    . The capability of the gated PILATUS detector to selectively detect the signal from a given X-ray pulse in 24 bunch mode at the APS storage ring is demonstrated. A test experiment performed on polycrystalline organic thin films of [alpha]-perylene illustrates the possibility of reaching an X-ray pulse duration......The recent developments in X-ray detectors have opened new possibilities in the area of time-resolved pump/probe X-ray experiments; this article presents the novel use of a PILATUS detector to achieve X-ray pulse duration limited time-resolution at the Advanced Photon Source (APS), USA...... limited time-resolution of 60 ps using the gated PILATUS detector. This is the first demonstration of X-ray pulse duration limited data recorded using an area detector without the use of a mechanical chopper array at the beamline....

  6. SR biomedical imaging with phase-contrast and fluorescent x-ray CT

    Science.gov (United States)

    Takeda, Tohoru; Wu, Jin; Yoneyama, Akio; Tsuchiya, Yoshinori; Lwin, Thet-Thet; Hirai, Yasuharu; Kuroe, Taichi; Yuasa, Tetsuya; Hyodo, Kazuyaki; Dilmanian, F. A.; Akatsuka, Takao

    2004-10-01

    New synchrotron x-ray CT system with phase-contrast and fluorescent techniques are being developed for biomedical researches with the high-contrast and high-spatial resolution. We have applied these techniques for in-vivo and ex-vivo imaging. The phase-contrast x-ray CT (PCCT) was a highly sensitive imaging technique to depict the morphological information of the soft tissue in biological object, whereas fluorescent x-ray CT (FXCT) could depict the functional information concerning to specific heavy atomic number elements at very low content. Thus, the success of in-vivo imaging by PCCT and FXCT allows starting new approach to bio-imaging researches.

  7. Time-resolved and position-resolved X-ray spectrometry with a pixelated detector

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, Peter

    2012-12-07

    show a good agreement. Up to now the measurements of impinging spectra with a Timepix detector have been performed in radiation fields with a relatively high fluence. To cope with the requirement of measuring in radiation fields with a low fluence, there had to be changes in the method of analysis compared to those performed formerly. An important improvement in this context was the employment of the Bayesian deconvolution method. The spectra reconstructed with this method were then compared to the results of two different and established detection systems. Firstly, the shape of the deconvolved spectrum was compared to the one measured with a hpGe detector. Secondly, the calculated value of the kerma rate was compared to the one measured with an ionization chamber. This gave an estimate on the correctness of the absolute number of photons. Both comparisons have shown a good agreement and thus I was able to validate that the method delivers precise results. Compared to the formerly used spectrum-stripping method the Bayesian deconvolution turned out to be very stable and reliable. This robustness of the deconvolution method and the development of a pixel-by-pixel energy calibration were the keys towards position-resolved spectrometry. With such a precise energy calibration the energy resolution was enhanced by up to 45%. This improved accuracy in the measurement has been very demanding on the improvements of the simulation of the response matrix needed for deconvolution. Both this enhanced simulation and a pixel-by-pixel calibrated detector opened the possibility of measuring the anode heel effect. Not only the relative angular dependency of the spectrum emitted but also the change in the absolute photon fluence were measured. Furthermore, it is possible to even use small ROIs down to 4x4 pixels to evaluate a spectrum. This was then applied for the spectrometry of small focal spots of a miniature X-ray source used in therapeutics. Furthermore, the robustness and the

  8. Elasticity and Anelasticity of Materials from Time-Resolved X-ray Diffraction

    Science.gov (United States)

    Sinogeikin, S. V.; Smith, J.; Lin, C.; Bai, L.; Rod, E.; Shen, G.

    2014-12-01

    Recent advances in synchrotron sources, x-ray optics, area detectors, and sample environment control have enabled many time-resolved experimental techniques for studying materials at extreme pressure and temperature conditions. The High Pressure Collaborative Access Team (HPCAT) at the Advanced Photon Source has made a sustained effort to develop and assemble a powerful collection of high-pressure apparatus for time-resolved research, and considerable time has been invested in developing techniques for collecting high-quality time-resolved x-ray scattering data. In this talk we will outline recently developed capabilities at HPCAT for studying elasticity and anelasticity of minerals using fast compression and cyclic compression-decompression. A few recent studies will be highlighted. For example, with fast x-ray area detectors having millisecond time resolution, accurate thermal equations of state of materials at temperatures up to 1000K and megabar pressures can be collected in a matter of seconds using membrane-driven diamond anvil cells (DAC), yielding unprecedented time and pressure resolution of true isotherms. Short duration of the experiments eliminates temperature variation during the experiments and in general allows volume measurements at higher pressures and temperatures. Alternatively, high-frequency (kilohertz range) radial diffraction measurements in a panoramic DAC combined with fast, precise cyclic loading/unloading by piezo drive could provide the short time scale necessary for studying rheology of minerals from the elastic response and lattice relaxation as a function of pressure, temperature and strain rate. Finally, we consider some possible future applications for time-resolved high-pressure, high-temperature research of mantle minerals.

  9. Quantitative X-ray fluorescence analysis of samples of less than `infinite thickness': Difficulties and possibilities

    Science.gov (United States)

    Sitko, Rafał

    2009-11-01

    X-ray fluorescence spectrometry due to its nondestructive nature is widely applied in analysis of single layers and multiple layer films (e.g. semiconductors, electrooptic and solar cell devices, coatings, corrosion and paint layers), individual particles (airborne, fly ash, gunshot residue particles, etc.), art and archeological objects (manuscripts, paintings, icons) and many others. Quantitative analysis of these materials, frequently classified as samples of less than infinite thickness (thin or intermediate-thickness samples), required applying adequate matrix correction methods taking into account complex dependence of analyte fluorescent radiation intensity on full matrix composition and sample thickness. In this article, the matrix correction methods including fundamental parameters, Monte Carlo simulations, influence coefficients algorithms and methods based on X-ray transmission measurements are reviewed. The difficulties in the analysis of single layer and multiple layer films and the accuracy of fundamental parameter methods in simultaneous determination of their thickness and composition are discussed. The quantitative analysis of individual particles and inhomogeneous and/or complex structure materials using fundamental parameter and Monte Carlo simulation methods in micro-beam X-ray fluorescence spectrometry are also reviewed. Some references are devoted to the analysis of light matrix samples, e.g. geological, environmental and biological samples, in which undetectable low-Z elements are present (so-called 'dark matrix') using backscattered fundamental parameter methods. Since the samples of less than infinite thickness are partially transparent for X-ray beams, the transmission measurements present possibilities that are unattainable for bulk samples. Thus, the emission-transmission method and also new instruments allowing measurements of the primary X-ray beam transmitted through the sample together with measurements of X-ray fluorescence

  10. Development of an X-ray fluorescence holographic measurement system for protein crystals

    Science.gov (United States)

    Sato-Tomita, Ayana; Shibayama, Naoya; Happo, Naohisa; Kimura, Koji; Okabe, Takahiro; Matsushita, Tomohiro; Park, Sam-Yong; Sasaki, Yuji C.; Hayashi, Kouichi

    2016-06-01

    Experimental procedure and setup for obtaining X-ray fluorescence hologram of crystalline metalloprotein samples are described. Human hemoglobin, an α2β2 tetrameric metalloprotein containing the Fe(II) heme active-site in each chain, was chosen for this study because of its wealth of crystallographic data. A cold gas flow system was introduced to reduce X-ray radiation damage of protein crystals that are usually fragile and susceptible to damage. A χ-stage was installed to rotate the sample while avoiding intersection between the X-ray beam and the sample loop or holder, which is needed for supporting fragile protein crystals. Huge hemoglobin crystals (with a maximum size of 8 × 6 × 3 mm3) were prepared and used to keep the footprint of the incident X-ray beam smaller than the sample size during the entire course of the measurement with the incident angle of 0°-70°. Under these experimental and data acquisition conditions, we achieved the first observation of the X-ray fluorescence hologram pattern from the protein crystals with minimal radiation damage, opening up a new and potential method for investigating the stereochemistry of the metal active-sites in biomacromolecules.

  11. Development of an X-ray fluorescence holographic measurement system for protein crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sato-Tomita, Ayana, E-mail: ayana.sato@jichi.ac.jp, E-mail: shibayam@jichi.ac.jp, E-mail: hayashi.koichi@nitech.ac.jp; Shibayama, Naoya, E-mail: ayana.sato@jichi.ac.jp, E-mail: shibayam@jichi.ac.jp, E-mail: hayashi.koichi@nitech.ac.jp; Okabe, Takahiro [Division of Biophysics, Department of Physiology, Jichi Medical University, Yakushiji, Shimotsuke 329-0498 (Japan); Happo, Naohisa [Department of Computer and Network Engineering, Graduate School of Information Sciences, Hiroshima City University, Asa-Minami-Ku, Hiroshima 731-3194 (Japan); Kimura, Koji [Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso, Showa, Nagoya 466-8555 (Japan); Matsushita, Tomohiro [Japan Synchrotron Radiation Research Institute (JASRI), SPring-8, Sayo, Hyogo 679-5198 (Japan); Park, Sam-Yong [Drug Design Laboratory, Department of Medical Life Science, Yokohama City University, Suehiro, Tsurumi, Yokohama 230-0045 (Japan); Sasaki, Yuji C. [Department of Advanced Material Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwanoha, Kashiwa 277-8561 (Japan); Hayashi, Kouichi, E-mail: ayana.sato@jichi.ac.jp, E-mail: shibayam@jichi.ac.jp, E-mail: hayashi.koichi@nitech.ac.jp [Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso, Showa, Nagoya 466-8555 (Japan); Frontier Research Institute for Materials Science, Nagoya Institute of Technology, Gokiso, Showa, Nagoya 466-8555 (Japan)

    2016-06-15

    Experimental procedure and setup for obtaining X-ray fluorescence hologram of crystalline metalloprotein samples are described. Human hemoglobin, an α{sub 2}β{sub 2} tetrameric metalloprotein containing the Fe(II) heme active-site in each chain, was chosen for this study because of its wealth of crystallographic data. A cold gas flow system was introduced to reduce X-ray radiation damage of protein crystals that are usually fragile and susceptible to damage. A χ-stage was installed to rotate the sample while avoiding intersection between the X-ray beam and the sample loop or holder, which is needed for supporting fragile protein crystals. Huge hemoglobin crystals (with a maximum size of 8 × 6 × 3 mm{sup 3}) were prepared and used to keep the footprint of the incident X-ray beam smaller than the sample size during the entire course of the measurement with the incident angle of 0°-70°. Under these experimental and data acquisition conditions, we achieved the first observation of the X-ray fluorescence hologram pattern from the protein crystals with minimal radiation damage, opening up a new and potential method for investigating the stereochemistry of the metal active-sites in biomacromolecules.

  12. X-ray fluorescence analysis study. Final report, December 1, 1970-December 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Kneip, T J; Laurer, G R

    1978-01-01

    This report has described the most significant experiments and the results obtained, during the development of a system for the detection and measurement of Pb in blood using radioisotope-excited x-ray fluorescence analysis, over the contract period. Briefly, the report described: detector selection; source selection; source-sample-detector geometry; sample preparation; system calibration; and separation technique. (PSB)

  13. Radiochemical Analysis by High Sensitivity Micro X-Ray Fluorescence Detection

    Energy Technology Data Exchange (ETDEWEB)

    Ning Gao

    2006-05-12

    The primary objective of the project was to develop a novel dual-optic x-ray fluorescence instrument capable of doing radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford Site.

  14. Archaeologist looks at x-ray fluorescence vs. neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Artzy, M.

    1976-04-01

    X-ray fluorescence (XRE) and neutron activation analysis (NAA) are compared; a periodic table of the elements showing their sensitivity to each method is included. It is proposed to use both methods to make chemical abundances measurements on archaeological samples, including Bichrome Ware and Palestinian samples. The intent is to see if NAA can be replaced by XRF. (DLC)

  15. X-Ray Fluorescence Analysis for Barium, Zinc, Calcium and Phosphorus in Oil Additives.

    Science.gov (United States)

    1983-08-01

    HOAlD-I’ 908 XRAY FLUORESCENCE ANALYSIS FOR BARIUM ZINC CALCIUM AND i/i PHOSPHORUS IN OIL HDDITIVES(U MATERIALS RESEARCH LABS ASCOT VALE (AUSTRALIA...film technique was used by McGinness, Scott and Mortensen [101 for the quantitative x-ray emission analysis of paints . The paint films, "one-half mil

  16. Quantitative analysis by synchrotron radiation induced X-ray fluorescence at lure

    Science.gov (United States)

    Chevallier, P.; Brissaud, I.; Wang, J. X.

    1990-04-01

    The main features that makes synchrotron radiation an ideal source for X-ray fluorescence analysis are emphasized. Examples of quantitative analysis are given and a new type of spectrometer taking advantage of the focusing properties of a flat mosaic crystal and a position sensitive detector is described.

  17. Novel energy resolving x-ray pinhole camera on Alcator C-Mod

    Energy Technology Data Exchange (ETDEWEB)

    Pablant, N. A.; Delgado-Aparicio, L.; Bitter, M.; Ellis, R.; Hill, K. W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Brandstetter, S.; Eikenberry, E.; Hofer, P.; Schneebeli, M. [Dectris Ltd., Baden (Switzerland)

    2012-10-15

    A new energy resolving x-ray pinhole camera has been recently installed on Alcator C-Mod. This diagnostic is capable of 1D or 2D imaging with a spatial resolution of Almost-Equal-To 1 cm, an energy resolution of Almost-Equal-To 1 keV in the range of 3.5-15 keV and a maximum time resolution of 5 ms. A novel use of a Pilatus 2 hybrid-pixel x-ray detector [P. Kraft et al., J. Synchrotron Rad. 16, 368 (2009)] is employed in which the lower energy threshold of individual pixels is adjusted, allowing regions of a single detector to be sensitive to different x-ray energy ranges. Development of this new detector calibration technique was done as a collaboration between PPPL and Dectris Ltd. The calibration procedure is described, and the energy resolution of the detector is characterized. Initial data from this installation on Alcator C-Mod is presented. This diagnostic provides line-integrated measurements of impurity emission which can be used to determine impurity concentrations as well as the electron energy distribution.

  18. Time-resolved x-ray diffraction techniques for bulk polycrystalline materials under dynamic loading.

    Science.gov (United States)

    Lambert, P K; Hustedt, C J; Vecchio, K S; Huskins, E L; Casem, D T; Gruner, S M; Tate, M W; Philipp, H T; Woll, A R; Purohit, P; Weiss, J T; Kannan, V; Ramesh, K T; Kenesei, P; Okasinski, J S; Almer, J; Zhao, M; Ananiadis, A G; Hufnagel, T C

    2014-09-01

    We have developed two techniques for time-resolved x-ray diffraction from bulk polycrystalline materials during dynamic loading. In the first technique, we synchronize a fast detector with loading of samples at strain rates of ~10(3)-10(4) s(-1) in a compression Kolsky bar (split Hopkinson pressure bar) apparatus to obtain in situ diffraction patterns with exposures as short as 70 ns. This approach employs moderate x-ray energies (10-20 keV) and is well suited to weakly absorbing materials such as magnesium alloys. The second technique is useful for more strongly absorbing materials, and uses high-energy x-rays (86 keV) and a fast shutter synchronized with the Kolsky bar to produce short (~40 μs) pulses timed with the arrival of the strain pulse at the specimen, recording the diffraction pattern on a large-format amorphous silicon detector. For both techniques we present sample data demonstrating the ability of these techniques to characterize elastic strains and polycrystalline texture as a function of time during high-rate deformation.

  19. Advancements in time-resolved x-ray laser induced time-of-flight photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A J; Dunn, J; Widmann, K; Ao, T; Ping, Y; Hunter, J; Ng, A

    2005-07-28

    Time-resolved soft x-ray photoelectron spectroscopy is used to probe the non-steady-state evolution of the valence band electronic structure of laser heated ultra-thin (50 nm) metal foils and bulk semiconductors. Single-shot soft x-ray laser induced time-of-flight photoelectron spectroscopy with picosecond time resolution was used in combination with optical measurements of the disassembly dynamics that have shown the existence of a metastable liquid phase in fs-laser heated metal foils persisting 4-5 ps. This metastable phase is studied using a 527 nm wavelength 400 fs laser pulse containing 0.3-2.5 mJ laser energy focused in a large 500 x 700 {micro}m{sup 2} spot to create heated conditions of 0.2-1.8 x 10{sup 12} W cm{sup -2} intensity. The unique LLNL COMET compact tabletop soft x-ray laser source provided the necessary high photon flux, highly monoenergetic, picosecond pulse duration, and coherence for observing the evolution of changes in the valence band electronic structure of laser heated metals and semiconductors with picosecond time resolution. This work demonstrates the continuing development of a powerful new technique for probing reaction dynamics and changes of local order on surfaces on their fundamental timescales including phenomena such as non-thermal melting, chemical bond formation, intermediate reaction steps, and the existence of transient reaction products.

  20. Time-resolved x-ray diffraction techniques for bulk polycrystalline materials under dynamic loading

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, P. K.; Hustedt, C. J.; Zhao, M.; Ananiadis, A. G.; Hufnagel, T. C. [Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Vecchio, K. S. [Department of NanoEngineering, University of California San Diego, La Jolla, California 92093 (United States); Huskins, E. L. [Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830 (United States); US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, Maryland 21005 (United States); Casem, D. T. [US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, Maryland 21005 (United States); Gruner, S. M. [Department of Physics, Cornell University, Ithaca, New York 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853 (United States); Tate, M. W.; Philipp, H. T.; Purohit, P.; Weiss, J. T. [Department of Physics, Cornell University, Ithaca, New York 14853 (United States); Woll, A. R. [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853 (United States); Kannan, V.; Ramesh, K. T. [Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Kenesei, P.; Okasinski, J. S.; Almer, J. [X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2014-09-15

    We have developed two techniques for time-resolved x-ray diffraction from bulk polycrystalline materials during dynamic loading. In the first technique, we synchronize a fast detector with loading of samples at strain rates of ∼10{sup 3}–10{sup 4} s{sup −1} in a compression Kolsky bar (split Hopkinson pressure bar) apparatus to obtain in situ diffraction patterns with exposures as short as 70 ns. This approach employs moderate x-ray energies (10–20 keV) and is well suited to weakly absorbing materials such as magnesium alloys. The second technique is useful for more strongly absorbing materials, and uses high-energy x-rays (86 keV) and a fast shutter synchronized with the Kolsky bar to produce short (∼40 μs) pulses timed with the arrival of the strain pulse at the specimen, recording the diffraction pattern on a large-format amorphous silicon detector. For both techniques we present sample data demonstrating the ability of these techniques to characterize elastic strains and polycrystalline texture as a function of time during high-rate deformation.

  1. Time-resolved X-ray Absorption Spectroscopy for Electron Transport Study in Warm Dense Gold

    Science.gov (United States)

    Lee, Jong-Won; Bae, Leejin; Engelhorn, Kyle; Heimann, Philip; Ping, Yuan; Barbrel, Ben; Fernandez, Amalia; Beckwith, Martha Anne; Cho, Byoung-Ick; GIST Team; IBS Team; LBNL Collaboration; SLAC Collaboration; LLNL Collaboration

    2015-11-01

    The warm dense Matter represents states of which the temperature is comparable to Fermi energy and ions are strongly coupled. One of the experimental techniques to create such state in the laboratory condition is the isochoric heating of thin metal foil with femtosecond laser pulses. This concept largely relies on the ballistic transport of electrons near the Fermi-level, which were mainly studied for the metals in ambient conditions. However, they were barely investigated in warm dense conditions. We present a time-resolved x-ray absorption spectroscopy measured for the Au/Cu dual layered sample. The front Au layer was isochorically heated with a femtosecond laser pulse, and the x-ray absorption changes around L-edge of Cu, which was attached on the backside of Au, was measured with a picosecond resolution. Time delays between the heating of the `front surface' of Au layer and the alternation of x-ray spectrum of Cu attached on the `rear surface' of Au indicate the energetic electron transport mechanism through Au in the warm dense conditions. IBS (IBS-R012-D1) and the NRF (No. 2013R1A1A1007084) of Korea.

  2. Novel energy resolving x-ray pinhole camera on Alcator C-Moda)

    Science.gov (United States)

    Pablant, N. A.; Delgado-Aparicio, L.; Bitter, M.; Brandstetter, S.; Eikenberry, E.; Ellis, R.; Hill, K. W.; Hofer, P.; Schneebeli, M.

    2012-10-01

    A new energy resolving x-ray pinhole camera has been recently installed on Alcator C-Mod. This diagnostic is capable of 1D or 2D imaging with a spatial resolution of ≈1 cm, an energy resolution of ≈1 keV in the range of 3.5-15 keV and a maximum time resolution of 5 ms. A novel use of a Pilatus 2 hybrid-pixel x-ray detector [P. Kraft et al., J. Synchrotron Rad. 16, 368 (2009), 10.1107/S0909049509009911] is employed in which the lower energy threshold of individual pixels is adjusted, allowing regions of a single detector to be sensitive to different x-ray energy ranges. Development of this new detector calibration technique was done as a collaboration between PPPL and Dectris Ltd. The calibration procedure is described, and the energy resolution of the detector is characterized. Initial data from this installation on Alcator C-Mod is presented. This diagnostic provides line-integrated measurements of impurity emission which can be used to determine impurity concentrations as well as the electron energy distribution.

  3. A von Hamos x-ray spectrometer based on a segmented-type diffraction crystal for single-shot x-ray emission spectroscopy and time-resolved resonant inelastic x-ray scattering studies.

    Science.gov (United States)

    Szlachetko, J; Nachtegaal, M; de Boni, E; Willimann, M; Safonova, O; Sa, J; Smolentsev, G; Szlachetko, M; van Bokhoven, J A; Dousse, J-Cl; Hoszowska, J; Kayser, Y; Jagodzinski, P; Bergamaschi, A; Schmitt, B; David, C; Lücke, A

    2012-10-01

    We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV-9600 eV. The use of a segmented crystal results in a simple and straightforward crystal preparation that allows to preserve the spectrometer resolution and spectrometer efficiency. Application of the spectrometer for time-resolved resonant inelastic x-ray scattering and single-shot x-ray emission spectroscopy is demonstrated.

  4. High-Resolving-Power, Streaked X-Ray Spectroscopy on the OMEGA EP Laser System

    Science.gov (United States)

    Nilson, P. M.; Ehrne, F.; Mileham, C.; Mastrosimone, D.; Jungquist, R. K.; Taylor, C.; Boni, R.; Hassett, J.; Stillman, C. R.; Ivancic, S. T.; Lonobile, D. J.; Kidder, R. W.; Shoup, M. J., III; Solodov, A. A.; Stoeckl, C.; Theobald, W.; Froula, D. H.; Hill, K. W.; Gao, L.; Bitter, M.; Efthimion, P.; Meyerhofer, D. D.

    2016-10-01

    A high-resolving-power, streaked x-ray spectrometer is being developed and tested on the OMEGA EP Laser System to study temperature-equilibration dynamics in rapidly heated solid matter. Temporal spectral shifts of the Cu Kα line in isochorically heated solid targets provide a fairly simple system where the spectrometer performance will be validated. The goal is to achieve a resolving power of several thousand and 2-ps temporal resolution. A time-integrating survey spectrometer has been developed and deployed on OMEGA EP to evaluate the throughput, focusing fidelity, and spectral resolution of two different crystal geometries. The results from these measurements will be presented and used to justify the down-selected time-resolved spectrometer design. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  5. High resolution x-ray fluorescence spectroscopy - a new technique for site- and spin-selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin [Univ. of California, Davis, CA (United States). Dept. of Applied Science

    1996-12-01

    X-ray spectroscopy has long been used to elucidate electronic and structural information of molecules. One of the weaknesses of x-ray absorption is its sensitivity to all of the atoms of a particular element in a sample. Through out this thesis, a new technique for enhancing the site- and spin-selectivity of the x-ray absorption has been developed. By high resolution fluorescence detection, the chemical sensitivity of K emission spectra can be used to identify oxidation and spin states; it can also be used to facilitate site-selective X-ray Absorption Near Edge Structure (XANES) and site-selective Extended X-ray Absorption Fine Structure (EXAFS). The spin polarization in K fluorescence could be used to generate spin selective XANES or spin-polarized EXAFS, which provides a new measure of the spin density, or the nature of magnetic neighboring atoms. Finally, dramatic line-sharpening effects by the combination of absorption and emission processes allow observation of structure that is normally unobservable. All these unique characters can enormously simplify a complex x-ray spectrum. Applications of this novel technique have generated information from various transition-metal model compounds to metalloproteins. The absorption and emission spectra by high resolution fluorescence detection are interdependent. The ligand field multiplet model has been used for the analysis of K{alpha} and K{beta} emission spectra. First demonstration on different chemical states of Fe compounds has shown the applicability of site selectivity and spin polarization. Different interatomic distances of the same element in different chemical forms have been detected using site-selective EXAFS.

  6. Full Field X-Ray Fluorescence Imaging Using Micro Pore Optics for Planetary Surface Exploration

    Science.gov (United States)

    Sarrazin, P.; Blake, D. F.; Gailhanou, M.; Walter, P.; Schyns, E.; Marchis, F.; Thompson, K.; Bristow, T.

    2016-01-01

    Many planetary surface processes leave evidence as small features in the sub-millimetre scale. Current planetary X-ray fluorescence spectrometers lack the spatial resolution to analyse such small features as they only provide global analyses of areas greater than 100 mm(exp 2). A micro-XRF spectrometer will be deployed on the NASA Mars 2020 rover to analyse spots as small as 120m. When using its line-scanning capacity combined to perpendicular scanning by the rover arm, elemental maps can be generated. We present a new instrument that provides full-field XRF imaging, alleviating the need for precise positioning and scanning mechanisms. The Mapping X-ray Fluorescence Spectrometer - "Map-X" - will allow elemental imaging with approximately 100µm spatial resolution and simultaneously provide elemental chemistry at the scale where many relict physical, chemical and biological features can be imaged in ancient rocks. The arm-mounted Map-X instrument is placed directly on the surface of an object and held in a fixed position during measurements. A 25x25 mm(exp 2) surface area is uniformly illuminated with X-rays or alpha-particles and gamma-rays. A novel Micro Pore Optic focusses a fraction of the emitted X-ray fluorescence onto a CCD operated at a few frames per second. On board processing allows measuring the energy and coordinates of each X-ray photon collected. Large sets of frames are reduced into 2d histograms used to compute higher level data products such as elemental maps and XRF spectra from selected regions of interest. XRF spectra are processed on the ground to further determine quantitative elemental compositions. The instrument development will be presented with an emphasis on the characterization and modelling of the X-ray focussing Micro Pore Optic. An outlook on possible alternative XRF imaging applications will be discussed.

  7. Modelling of the X-ray fluorescence from Mercury's surface and sodium exosphere

    Science.gov (United States)

    Cooper, Rose

    2016-10-01

    We model the fluorescent X-ray signal expected from the Mercury surface. Due to the high solar flux at Mercury, it represents a highly suitable target. Observations of this fluorescence will be performed by the Mercury Imaging X-ray Spectrometer (MIXS) on the upcoming BepiColumbo mission. Accurate modelling is required to plan observation strategies and eventually to quantify the surface composition. In addition, we also investigate the possibility of detecting fluorescence from the exosphere. We are using code modified from that used for the SMART-1 D-CIXS instrument to the Moon. Modifications include detector parameters, solar proximity, likely surface elemental components, and emission from the optically thin exosphere. Modelling of fluorescence from both the surface and exosphere are conducted, with particular emphasis on the sodium component.

  8. Soft x-ray blazed transmission grating spectrometer with high resolving power and extended bandpass

    Science.gov (United States)

    Heilmann, Ralf K.; Bruccoleri, Alexander Robert; Schattenburg, Mark

    2016-04-01

    A number of high priority questions in astrophysics can be addressed by a state-of-the-art soft x-ray grating spectrometer, such as the role of Active Galactic Nuclei in galaxy and star formation, characterization of the Warm-Hot Intergalactic Medium and the “missing baryon” problem, characterization of halos around the Milky Way and nearby galaxies, as well as stellar coronae and surrounding winds and disks. An Explorer-scale, large-area (> 1,000 cm2), high resolving power (R = λ/Δλ > 3,000) soft x-ray grating spectrometer is highly feasible based on Critical-Angle Transmission (CAT) grating technology. Still significantly higher performance can be provided by a CAT grating spectrometer on an X-ray-Surveyor-type mission. CAT gratings combine the advantages of blazed reflection gratings (high efficiency, use of higher diffraction orders) with those of conventional transmission gratings (low mass, relaxed alignment tolerances and temperature requirements, transparent at higher energies) with minimal mission resource requirements. They are high-efficiency blazed transmission gratings that consist of freestanding, ultra-high aspect-ratio grating bars fabricated from silicon-on-insulator (SOI) wafers using advanced anisotropic dry and wet etch techniques. Blazing is achieved through grazing-incidence reflection off the smooth grating bar sidewalls. The reflection properties of silicon are well matched to the soft x-ray band. Nevertheless, CAT gratings with sidewalls made of higher atomic number elements allow extension of the CAT grating principle to higher energies and larger dispersion angles. We show x-ray data from metal-coated CAT gratings and demonstrate efficient blazing to higher energies and larger blaze angles than possible with silicon alone. We also report on measurements of the resolving power of a breadboard CAT grating spectrometer consisting of a Wolter-I slumped-glass focusing mirror pair from Goddard Space Flight Center and CAT gratings, to be

  9. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources.

    Science.gov (United States)

    Rutherford, Michael E; Chapman, David J; White, Thomas G; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E

    2016-05-01

    The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits).

  10. Particle tracking during Ostwald ripening using time-resolved laboratory X-ray microtomography

    Energy Technology Data Exchange (ETDEWEB)

    Werz, T., E-mail: thomas.werz@uni-ulm.de [Ulm University, Institute of Micro and Nanomaterials, Albert-Einstein-Allee 47, 89081 (Germany); Baumann, M. [Ulm University, Institute of Micro and Nanomaterials, Albert-Einstein-Allee 47, 89081 (Germany); Wolfram, U. [Ulm University, Institute of Orthopaedic Research and Biomechanics, Helmholtzstrasse 14, 89081 (Germany); Krill, C.E. [Ulm University, Institute of Micro and Nanomaterials, Albert-Einstein-Allee 47, 89081 (Germany)

    2014-04-01

    Laboratory X-ray microtomography is investigated as a method for obtaining time-resolved images of microstructural coarsening of the semisolid state of Al–5 wt.% Cu samples during Ostwald ripening. Owing to the 3D imaging capability of tomography, this technique uniquely provides access to the growth rates of individual particles, thereby not only allowing a statistical characterization of coarsening—as has long been possible by conventional metallography—but also enabling quantification of the influence of local environment on particle boundary migration. The latter information is crucial to understanding growth kinetics during Ostwald ripening at high volume fractions of the coarsening phase. Automated image processing and segmentation routines were developed to close gaps in the network of particle boundaries and to track individual particles from one annealing step to the next. The particle tracking success rate places an upper bound of only a few percent on the likelihood of segmentation errors for any given particle. The accuracy of particle size trajectories extracted from the time-resolved tomographic reconstructions is correspondingly high. Statistically averaged coarsening data and individual particle growth rates are in excellent agreement with the results of prior experimental studies and with computer simulations of Ostwald ripening. - Highlights: • Ostwald ripening in Al–5 wt.% Cu measured by laboratory X-ray microtomography • Time-resolved measurement of individual particle growth • Automated segmentation routines developed to close gaps in particle boundary network • Particle growth/shrinkage rates deviate from LSW model prediction.

  11. Time-resolved coherent X-ray diffraction imaging of surface acoustic waves.

    Science.gov (United States)

    Nicolas, Jan-David; Reusch, Tobias; Osterhoff, Markus; Sprung, Michael; Schülein, Florian J R; Krenner, Hubert J; Wixforth, Achim; Salditt, Tim

    2014-10-01

    Time-resolved coherent X-ray diffraction experiments of standing surface acoustic waves, illuminated under grazing incidence by a nanofocused synchrotron beam, are reported. The data have been recorded in stroboscopic mode at controlled and varied phase between the acoustic frequency generator and the synchrotron bunch train. At each time delay (phase angle), the coherent far-field diffraction pattern in the small-angle regime is inverted by an iterative algorithm to yield the local instantaneous surface height profile along the optical axis. The results show that periodic nanoscale dynamics can be imaged at high temporal resolution in the range of 50 ps (pulse length).

  12. Time-resolved X-ray diffraction of Ti in dynamic-DAC

    Science.gov (United States)

    Tomasino, Dane; Yoo, Choong-Shik

    2017-01-01

    Understanding the dynamic response of solids under extreme conditions of pressure, temperature and strain rate is a fundamental scientific quest and a basic research need in materials science. Specifically, obtaining an atomistic description of structural and chemical changes of solids under rapid heating and/or compression over a large temporal, spatial and energy range is challenging but critical to understanding material stability or metastable structure, chemical mechanism, transition dynamic, and mechanical deformation. In this paper, we present time-resolved synchrotron x-ray diffraction probing the structural evolution of Ti across the α-ω phase transition in dynamic-diamond anvil cell.

  13. X-ray fluorescence microtomography of SiC shells

    Energy Technology Data Exchange (ETDEWEB)

    Ice, G.E.; Chung, J.S. [Oak Ridge National Lab., TN (United States); Nagedolfeizi, M. [Univ. of Tennessee, Knoxville, TN (United States)

    1997-04-01

    TRISCO coated fuel particles contain a small kernel of nuclear fuel encapsulated by alternating layers of C and SiC. The TRISCO coated fuel particle is used in an advanced fuel designed for passive containment of the radioactive isotopes. The SiC layer provides the primary barrier for radioactive elements in the kernel. The effectiveness of this barrier layer under adverse conditions is critical to containment. The authors have begun the study of SiC shells from TRISCO fuel. They are using the fluorescent microprobe beamline 10.3.1. The shells under evaluation include some which have been cycled through a simulated core melt-down. The C buffer layers and nuclear kernels of the coated fuel have been removed by laser drilling through the SiC and then exposing the particle to acid. Elements of interest include Ru, Sb, Cs, Ce and Eu. The radial distribution of these elements in the SiC shells can be attributed to diffusion of elements in the kernel during the melt-down. Other elements in the shells originate during the fabrication of the TRISCO particles.

  14. Size-resolved source apportionment of aerosol particles using polycapillary X-ray lens with a plateau in its focal spot

    Energy Technology Data Exchange (ETDEWEB)

    Sun Tianxi, E-mail: stxbeijing@163.co [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China) and Key Laboratory of Evidence Science of Ministry of Education, China University of Political Science and Law, Beijing 100875 (China) and College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China) and Beijing Radiation Center, Beijing 100875 (China); Liu Zhiguo; Li Yude; Wang Guangpu; Zhu Guanghua [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Key Laboratory of Evidence Science of Ministry of Education, China University of Political Science and Law, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xu Qing [Institute of High Energy Physics, Chinese Academy of Science, Beijing 100039 (China); Ma Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Lin Xiaoyan; Liu Hui; Luo Ping; Pan Qiuli; Teng Yuepeng; Ding Xunliang [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Key Laboratory of Evidence Science of Ministry of Education, China University of Political Science and Law, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2010-12-15

    A laboratory micro X-ray fluorescence spectrometer based on a special polycapillary X-ray lens (PXRL) was used to carry out the source apportionment of aerosol particles. In the curve of the distribution of the X-ray intensity in the focal spot of the special PXRL, there was a plateau with a diameter of 21.3 {mu}m in which the distribution of the X-ray intensity was homogeneous. The gain in flux density in the plateau of the PXRL is 1490. The uniformity of this plateau was 2.9%. This was helpful for the quantitative X-ray fluorescence analysis of a single aerosol particle with smaller size than that of the plateau of the PXRL. The fingerprint database of aerosol particles with given sizes from various air pollution sources was established with the single particle analysis method. The size-resolved source apportionment of aerosol particles in haze in Beijing city was performed with this fingerprint database.

  15. Using Synchrotron X-ray Fluorescence Microprobes in the Study of Metal Homeostasis in Plants

    Energy Technology Data Exchange (ETDEWEB)

    Punshon, T.; Guerinot, M; Lanzirotti, A

    2009-01-01

    Background and Aims: This Botanical Briefing reviews the application of synchrotron X-ray fluorescence (SXRF) microprobes to the plant sciences; how the technique has expanded our knowledge of metal(loid) homeostasis, and how it can be used in the future. Scope: The use of SXRF microspectroscopy and microtomography in research on metal homeostasis in plants is reviewed. The potential use of SXRF as part of the ionomics toolbox, where it is able to provide fundamental information on the way that plants control metal homeostasis, is recommended. Conclusions: SXRF is one of the few techniques capable of providing spatially resolved in-vivo metal abundance data on a sub-micrometre scale, without the need for chemical fixation, coating, drying or even sectioning of samples. This gives researchers the ability to uncover mechanisms of plant metal homeostasis that can potentially be obscured by the artefacts of sample preparation. Further, new generation synchrotrons with smaller beam sizes and more sensitive detection systems will allow for the imaging of metal distribution within single living plant cells. Even greater advances in our understanding of metal homeostasis in plants can be gained by overcoming some of the practical boundaries that exist in the use of SXRF analysis.

  16. Comparing the Ag-content of poltinniks using X-ray fluorescence

    CERN Document Server

    Ferguson, S

    2013-01-01

    X-ray fluorescence experiments have been performed in order to analyze the elemental composition of four Russian 50-kopek coins ("poltinniks") minted during 1913, 1921, and 1924. By comparing the intensities of the Ag K{\\alpha} X-rays emitted by the poltinniks, we were able to determine whether the Ag-content of the coins were equal. One of the goals of this study was to determine whether or not legislation was carried out that required the proportions of Ag and Cu used in the minting of coins in 1924 to be identical to those minted in previous years. Also, the intensities of the Ag K{\\alpha} X-rays emitted by 1924 poltinniks minted in London and Leningrad were compared. Our results suggest that the percent difference in the proportions of Ag present in each of the coins is no more than 5.5%.

  17. Capturing interfacial photoelectrochemical dynamics with picosecond time-resolved X-ray photoelectron spectroscopy.

    Science.gov (United States)

    Neppl, Stefan; Shavorskiy, Andrey; Zegkinoglou, Ioannis; Fraund, Matthew; Slaughter, Daniel S; Troy, Tyler; Ziemkiewicz, Michael P; Ahmed, Musahid; Gul, Sheraz; Rude, Bruce; Zhang, Jin Z; Tremsin, Anton S; Glans, Per-Anders; Liu, Yi-Sheng; Wu, Cheng Hao; Guo, Jinghua; Salmeron, Miquel; Bluhm, Hendrik; Gessner, Oliver

    2014-01-01

    Time-resolved core-level spectroscopy using laser pulses to initiate and short X-ray pulses to trace photoinduced processes has the unique potential to provide electronic state- and atomic site-specific insight into fundamental electron dynamics in complex systems. Time-domain studies using transient X-ray absorption and emission techniques have proven extremely valuable to investigate electronic and structural dynamics in isolated and solvated molecules. Here, we describe the implementation of a picosecond time-resolved X-ray photoelectron spectroscopy (TRXPS) technique at the Advanced Light Source (ALS) and its application to monitor photoinduced electron dynamics at the technologically pertinent interface formed by N3 dye molecules anchored to nanoporous ZnO. Indications for a dynamical chemical shift of the Ru3d photoemission line originating from the N3 metal centre are observed ∼30 ps after resonant HOMO-LUMO excitation with a visible laser pump pulse. The transient changes in the TRXPS spectra are accompanied by a characteristic surface photovoltage (SPV) response of the ZnO substrate on a pico- to nanosecond time scale. The interplay between the two phenomena is discussed in the context of possible electronic relaxation and recombination pathways that lead to the neutralisation of the transiently oxidised dye after ultrafast electron injection. A detailed account of the experimental technique is given including an analysis of the chemical modification of the nano-structured ZnO substrate during extended periods of solution-based dye sensitisation and its relevance for studies using surface-sensitive spectroscopy techniques.

  18. Application of X-ray fluorescence analytical techniques in phytoremediation and plant biology studies

    Science.gov (United States)

    Nečemer, Marijan; Kump, Peter; Ščančar, Janez; Jaćimović, Radojko; Simčič, Jurij; Pelicon, Primož; Budnar, Miloš; Jeran, Zvonka; Pongrac, Paula; Regvar, Marjana; Vogel-Mikuš, Katarina

    2008-11-01

    Phytoremediation is an emerging technology that employs the use of higher plants for the clean-up of contaminated environments. Progress in the field is however handicapped by limited knowledge of the biological processes involved in plant metal uptake, translocation, tolerance and plant-microbe-soil interactions; therefore a better understanding of the basic biological mechanisms involved in plant/microbe/soil/contaminant interactions would allow further optimization of phytoremediation technologies. In view of the needs of global environmental protection, it is important that in phytoremediation and plant biology studies the analytical procedures for elemental determination in plant tissues and soil should be fast and cheap, with simple sample preparation, and of adequate accuracy and reproducibility. The aim of this study was therefore to present the main characteristics, sample preparation protocols and applications of X-ray fluorescence-based analytical techniques (energy dispersive X-ray fluorescence spectrometry—EDXRF, total reflection X-ray fluorescence spectrometry—TXRF and micro-proton induced X-ray emission—micro-PIXE). Element concentrations in plant leaves from metal polluted and non-polluted sites, as well as standard reference materials, were analyzed by the mentioned techniques, and additionally by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). The results were compared and critically evaluated in order to assess the performance and capability of X-ray fluorescence-based techniques in phytoremediation and plant biology studies. It is the EDXRF, which is recommended as suitable to be used in the analyses of a large number of samples, because it is multi-elemental, requires only simple preparation of sample material, and it is analytically comparable to the most frequently used instrumental chemical techniques. The TXRF is compatible to FAAS in sample preparation, but relative to AAS it is fast

  19. Micro X-ray Fluorescence Imaging in a Tabletop Full Field-X-ray Fluorescence Instrument and in a Full Field-Particle Induced X-ray Emission End Station.

    Science.gov (United States)

    Romano, Francesco Paolo; Caliri, Claudia; Cosentino, Luigi; Gammino, Santo; Mascali, David; Pappalardo, Lighea; Rizzo, Francesca; Scharf, Oliver; Santos, Hellen Cristine

    2016-10-08

    A full field-X-ray camera (FF-XRC) was developed for performing the simultaneous mapping of chemical elements with a high lateral resolution. The device is based on a conventional CCD detector coupled to a straight shaped polycapillary. Samples are illuminated at once with a broad primary beam that can consist of X-rays or charged particles in two different analytical setups. The characteristic photons induced in the samples are guided by the polycapillary to the detector allowing the elemental imaging without the need for scanning. A single photon counting detection operated in a multiframe acquisition mode and a processing algorithm developed for event hitting reconstruction have enabled one to use the CCD as a high energy resolution X-ray detector. A novel software with a graphical user interface (GUI) programmed in Matlab allows full control of the device and the real-time imaging with a region-of-interest (ROI) method. At the end of the measurement, the software produces spectra for each of the pixels in the detector allowing the application of a least-squares fitting with external analytical tools. The FF-XRC is very compact and can be installed in different experimental setups. This work shows the potentialities of the instrument in both a full field-micro X-ray fluorescence (FF-MXRF) tabletop device and in a full field-micro particle induced X-ray emission (FF-MPIXE) end-station operated with an external proton beam. Some examples of applications are given as well.

  20. Soft-x-ray fluorescence study of buried silicides in antiferromagnetically coupled Fe/Si multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Carlisle, J.A.; Chaiken, A.; Michel, R.P. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Multilayer films made by alternate deposition of two materials play an important role in electronic and optical devices such as quantum-well lasers and x-ray mirrors. In addition, novel phenomena like giant magnetoresistance and dimensional crossover in superconductors have emerged from studies of multilayers. While sophisticated x-ray techniques are widely used to study the morphology of multilayer films, progress in studying the electronic structure has been slower. The short mean-free path of low-energy electrons severely limits the usefulness of photoemission and related electron free path of low-energy electrons severely limit spectroscopies for multilayer studies. Soft x-ray fluorescence (SXF) is a bulk-sensitive photon-in, photon-out method to study valence band electronic states. Near-edge x-ray absorption fine-structure spectroscopy (NEXAFS) measured with partial photon yield can give complementary bulk-sensitive information about unoccupied states. Both these methods are element-specific since the incident x-ray photons excite electrons from core levels. By combining NEXAFS and SXF measurements on buried layers in multilayers and comparing these spectra to data on appropriate reference compounds, it is possible to obtain a detailed picture of the electronic structure. Results are presented for a study of a Fe/Si multilayer system.

  1. X-ray fluorescence analysis of low concentrations metals in geological samples and technological products

    Science.gov (United States)

    Lagoida, I. A.; Trushin, A. V.

    2016-02-01

    For the past several years many nuclear physics methods of quantitative elemental analysis have been designed. Many of these methods have applied in different devices which have become useful and effective instrument in many industrial laboratories. Methods of a matter structure analysis are based on the intensity detection of the X-ray radiation from the nuclei of elements which are excited by external X-ray source. The production of characteristic X-rays involves transitions of the orbital electrons of atoms in the target material between allowed orbits, or energy states, associated with ionization of the inner atomic shells. One of these methods is X-ray fluorescence analysis, which is widespread in metallurgical and processing industries and is used to identify and measure the concentration of the elements in ores and minerals on a conveyor belt. Samples of copper ore with known concentrations of elements, were taken from the Ural deposit. To excite the characteristic X-rays radionuclide sources 109Cd, with half-life 461.4 days were used. After finding the calibration coefficients, control measurements of samples and averaging of overall samples were made. The measurement error did not exceed 3%.

  2. Analytical characterization of a new mobile X-ray fluorescence and X-ray diffraction instrument combined with a pigment identification case study

    Energy Technology Data Exchange (ETDEWEB)

    Van de Voorde, Lien, E-mail: lien.vandevoorde@ugent.be [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Vekemans, Bart [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Verhaeven, Eddy [Antwerp University, Faculty of Design Sciences, Mutsaardstraat 31, B-2000 Antwerpen (Belgium); Tack, Pieter; De Wolf, Robin; Garrevoet, Jan [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Vandenabeele, Peter [Ghent University, Department of Archaeology, Archaeometry Research Group, Sint-Pietersnieuwstraat 35, B-9000 Gent (Belgium); Vincze, Laszlo [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium)

    2015-08-01

    A new, commercially available, mobile system combining X-ray diffraction and X-ray fluorescence has been evaluated which enables both elemental analysis and phase identification simultaneously. The instrument makes use of a copper or molybdenum based miniature X-ray tube and a silicon-Pin diode energy-dispersive detector to count the photons originating from the samples. The X-ray tube and detector are both mounted on an X-ray diffraction protractor in a Bragg–Brentano θ:θ geometry. The mobile instrument is one of the lightest and most compact instruments of its kind (3.5 kg) and it is thus very useful for in situ purposes such as the direct (non-destructive) analysis of cultural heritage objects which need to be analyzed on site without any displacement. The supplied software allows both the operation of the instrument for data collection and in-depth data analysis using the International Centre for Diffraction Data database. This paper focuses on the characterization of the instrument, combined with a case study on pigment identification and an illustrative example for the analysis of lead alloyed printing letters. The results show that this commercially available light-weight instrument is able to identify the main crystalline phases non-destructively, present in a variety of samples, with a high degree of flexibility regarding sample size and position. - Highlights: • New X-ray fluorescence and X-ray diffraction instrument for non-destructive analysis • Commercially available, mobile system • One of the lightest and most compact of its kind • Characterization, data acquisition and analysis are performed. • Results of measurements on pigment model samples and cultural heritage materials.

  3. The complex ion structure of warm dense carbon measured by spectrally resolved x-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, D.; Barbrel, B.; Falcone, R. W. [Department of Physics, University of California, Berkeley, California 94720 (United States); Vorberger, J. [Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, 01187 Dresden (Germany); Helfrich, J.; Frydrych, S.; Ortner, A.; Otten, A.; Roth, F.; Schaumann, G.; Schumacher, D.; Siegenthaler, K.; Wagner, F.; Roth, M. [Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt (Germany); Gericke, D. O.; Wünsch, K. [Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Bachmann, B.; Döppner, T. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Bagnoud, V.; Blažević, A. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany); and others

    2015-05-15

    We present measurements of the complex ion structure of warm dense carbon close to the melting line at pressures around 100 GPa. High-pressure samples were created by laser-driven shock compression of graphite and probed by intense laser-generated x-ray sources with photon energies of 4.75 keV and 4.95 keV. High-efficiency crystal spectrometers allow for spectrally resolving the scattered radiation. Comparing the ratio of elastically and inelastically scattered radiation, we find evidence for a complex bonded liquid that is predicted by ab-initio quantum simulations showing the influence of chemical bonds under these conditions. Using graphite samples of different initial densities we demonstrate the capability of spectrally resolved x-ray scattering to monitor the carbon solid-liquid transition at relatively constant pressure of 150 GPa. Showing first single-pulse scattering spectra from cold graphite of unprecedented quality recorded at the Linac Coherent Light Source, we demonstrate the outstanding possibilities for future high-precision measurements at 4th Generation Light Sources.

  4. Scanning X-ray nanodiffraction: from the experimental approach towards spatially resolved scattering simulations

    OpenAIRE

    Dubslaff, Martin; Hanke, Michael; Patommel, Jens; Hoppe, Robert; Schroer, Christian G.; Schöder, Sebastian; Burghammer, Manfred

    2012-01-01

    An enhancement on the method of X-ray diffraction simulations for applications using nanofocused hard X-ray beams is presented. We combine finite element method, kinematical scattering calculations, and a spot profile of the X-ray beam to simulate the diffraction of definite parts of semiconductor nanostructures. The spot profile could be acquired experimentally by X-ray ptychography. Simulation results are discussed and compared with corresponding X-ray nanodiffraction experiments on single ...

  5. Developments in time-resolved high pressure x-ray diffraction using rapid compression and decompression

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jesse S.; Sinogeikin, Stanislav V.; Lin, Chuanlong; Rod, Eric; Bai, Ligang; Shen, Guoyin [High Pressure Collaborative Access Team, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States)

    2015-07-15

    Complementary advances in high pressure research apparatus and techniques make it possible to carry out time-resolved high pressure research using what would customarily be considered static high pressure apparatus. This work specifically explores time-resolved high pressure x-ray diffraction with rapid compression and/or decompression of a sample in a diamond anvil cell. Key aspects of the synchrotron beamline and ancillary equipment are presented, including source considerations, rapid (de)compression apparatus, high frequency imaging detectors, and software suitable for processing large volumes of data. A number of examples are presented, including fast equation of state measurements, compression rate dependent synthesis of metastable states in silicon and germanium, and ultrahigh compression rates using a piezoelectric driven diamond anvil cell.

  6. Focused beam total reflection X-ray fluorescence with low power sources coupled to doubly curved crystal optics

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z.W. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States)]. E-mail: zchen@xos.com; Mail, N. [Center For X-ray Optics, State University of New York, University at Albany (United States); Wei, F.Z. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States); MacDonald, C.A. [Center For X-ray Optics, State University of New York, University at Albany (United States); Gibson, W.M. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States)

    2005-04-30

    A focused beam total X-ray fluorescence technique was developed based on doubly curved crystal optics. This technique provides good detection sensitivity and spatial resolution for localized detection of surface deposits. Compact low power X-ray sources were used to demonstrate the benefit of the X-ray optics for focusing Cr K{alpha}, Cu K{alpha} and Mo K{alpha} radiation. The detection capability of the focused beam Total reflection X-ray fluorescence system was investigated with dried droplets of calibrated low concentration solutions. Detection limits at the femtogram level were demonstrated.

  7. Optimizing detector geometry for trace element mapping by X-ray fluorescence.

    Science.gov (United States)

    Sun, Yue; Gleber, Sophie-Charlotte; Jacobsen, Chris; Kirz, Janos; Vogt, Stefan

    2015-05-01

    Trace metals play critical roles in a variety of systems, ranging from cells to photovoltaics. X-Ray Fluorescence (XRF) microscopy using X-ray excitation provides one of the highest sensitivities available for imaging the distribution of trace metals at sub-100 nm resolution. With the growing availability and increasing performance of synchrotron light source based instruments and X-ray nanofocusing optics, and with improvements in energy-dispersive XRF detectors, what are the factors that limit trace element detectability? To address this question, we describe an analytical model for the total signal incident on XRF detectors with various geometries, including the spectral response of energy dispersive detectors. This model agrees well with experimentally recorded X-ray fluorescence spectra, and involves much shorter calculation times than with Monte Carlo simulations. With such a model, one can estimate the signal when a trace element is illuminated with an X-ray beam, and when just the surrounding non-fluorescent material is illuminated. From this signal difference, a contrast parameter can be calculated and this can in turn be used to calculate the signal-to-noise ratio (S/N) for detecting a certain elemental concentration. We apply this model to the detection of trace amounts of zinc in biological materials, and to the detection of small quantities of arsenic in semiconductors. We conclude that increased detector collection solid angle is (nearly) always advantageous even when considering the scattered signal. However, given the choice between a smaller detector at 90° to the beam versus a larger detector at 180° (in a backscatter-like geometry), the 90° detector is better for trace element detection in thick samples, while the larger detector in 180° geometry is better suited to trace element detection in thin samples.

  8. Observation of X-ray shadings in synchrotron radiation-total reflection X-ray fluorescence using a color X-ray camera

    Energy Technology Data Exchange (ETDEWEB)

    Fittschen, Ursula Elisabeth Adriane, E-mail: ursula.fittschen@chemie.uni-hamburg.de [Institut für Anorganische und Angewandte Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Menzel, Magnus [Institut für Anorganische und Angewandte Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Scharf, Oliver [IfG Institute for Scientific Instruments GmbH, Berlin (Germany); Radtke, Martin; Reinholz, Uwe; Buzanich, Günther [BAM Federal Institute of Materials Research and Testing, Berlin (Germany); Lopez, Velma M.; McIntosh, Kathryn [Los Alamos National Laboratory, Los Alamos, NM (United States); Streli, Christina [Atominstitut, TU Wien, Vienna (Austria); Havrilla, George Joseph [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2014-09-01

    Absorption effects and the impact of specimen shape on TXRF analysis has been discussed intensively. Model calculations indicated that ring shaped specimens should give better results in terms of higher counts per mass signals than filled rectangle or circle shaped specimens. One major reason for the difference in signal is shading effects. Full field micro-XRF with a color X-ray camera (CXC) was used to investigate shading, which occurs when working with small angles of excitation as in TXRF. The device allows monitoring the illuminated parts of the sample and the shaded parts at the same time. It is expected that sample material hit first by the primary beam shade material behind it. Using the CXC shading could be directly visualized for the high concentration specimens. In order to compare the experimental results with calculation of the shading effect the generation of controlled specimens is crucial. This was achieved by “drop on demand” technology. It allows generating uniform, microscopic deposits of elements. The experimentally measured shadings match well with those expected from calculation. - Highlights: • Use of a color X-ray camera and drop on demand printing to diagnose X-ray shading • Specimens were obtained uniform and well-defined in shape and concentration by printing. • Direct visualization and determination of shading in such specimens using the camera.

  9. Energetic electron processes fluorescence effects for structured nanoparticles X-ray analysis and nuclear medicine applications

    Energy Technology Data Exchange (ETDEWEB)

    Taborda, A.; Desbrée, A. [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SDI/LEDI, BP-17, 31, Avenue de la Division Leclerc, 92262 Fontenay-aux-Roses (France); Carvalho, A. [IEQUALTECS, Lda, Rua Dr. Francisco Sá Carneiro, 36, 2500-065 S. Gregório CLD (Portugal); Chaves, P.C. [C" 2TN, Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, EN10 km 139.7, 2685-066 Bobadela LRS (Portugal); Reis, M.A., E-mail: mareis@ctn.tecnico.ulisboa.pt [IEQUALTECS, Lda, Rua Dr. Francisco Sá Carneiro, 36, 2500-065 S. Gregório CLD (Portugal); C" 2TN, Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, EN10 km 139.7, 2685-066 Bobadela LRS (Portugal)

    2016-08-15

    Superparamagnetic iron oxide (SPIO) nanoparticles are widely used as contrast agents for nuclear magnetic resonance imaging (MRI), and can be modified for improved imaging or to become tissue-specific or even protein-specific. The knowledge of their detailed elemental composition characterisation and potential use in nuclear medicine applications, is, therefore, an important issue. X-ray fluorescence techniques such as particle induced X-ray emission (PIXE) or X-ray fluorescence spectrometry (XRF), can be used for elemental characterisation even in problematic situations where very little sample volume is available. Still, the fluorescence coefficient of Fe is such that, during the decay of the inner-shell ionised atomic structure, keV Auger electrons are produced in excess to X-rays. Since cross-sections for ionisation induced by keV electrons, for low atomic number atoms, are of the order of 10{sup 3} barn, care should be taken to account for possible fluorescence effects caused by Auger electrons, which may lead to the wrong quantification of elements having atomic number lower than the atomic number of Fe. Furthermore, the same electron processes will occur in iron oxide nanoparticles containing {sup 57}Co, which may be used for nuclear medicine therapy purposes. In the present work, simple approximation algorithms are proposed for the quantitative description of radiative and non-radiative processes associated with Auger electrons cascades. The effects on analytical processes and nuclear medicine applications are quantified for the case of iron oxide nanoparticles, by calculating both electron fluorescence emissions and energy deposition on cell tissues where the nanoparticles may be embedded.

  10. Energetic electron processes fluorescence effects for structured nanoparticles X-ray analysis and nuclear medicine applications

    Science.gov (United States)

    Taborda, A.; Desbrée, A.; Carvalho, A.; Chaves, P. C.; Reis, M. A.

    2016-08-01

    Superparamagnetic iron oxide (SPIO) nanoparticles are widely used as contrast agents for nuclear magnetic resonance imaging (MRI), and can be modified for improved imaging or to become tissue-specific or even protein-specific. The knowledge of their detailed elemental composition characterisation and potential use in nuclear medicine applications, is, therefore, an important issue. X-ray fluorescence techniques such as particle induced X-ray emission (PIXE) or X-ray fluorescence spectrometry (XRF), can be used for elemental characterisation even in problematic situations where very little sample volume is available. Still, the fluorescence coefficient of Fe is such that, during the decay of the inner-shell ionised atomic structure, keV Auger electrons are produced in excess to X-rays. Since cross-sections for ionisation induced by keV electrons, for low atomic number atoms, are of the order of 103 barn, care should be taken to account for possible fluorescence effects caused by Auger electrons, which may lead to the wrong quantification of elements having atomic number lower than the atomic number of Fe. Furthermore, the same electron processes will occur in iron oxide nanoparticles containing 57Co, which may be used for nuclear medicine therapy purposes. In the present work, simple approximation algorithms are proposed for the quantitative description of radiative and non-radiative processes associated with Auger electrons cascades. The effects on analytical processes and nuclear medicine applications are quantified for the case of iron oxide nanoparticles, by calculating both electron fluorescence emissions and energy deposition on cell tissues where the nanoparticles may be embedded.

  11. X-Ray Tomographic Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bonnie Schmittberger

    2010-08-25

    Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular x-ray scans. X-Ray fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron x-rays and detects the fluorescent photons emitted from the sample. However, since x-rays are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the x-rays have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.

  12. X-ray fluorescence computed tomography (XFCT) imaging of gold nanoparticle-loaded objects using 110 kVp x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Seong-Kyun; Jones, Bernard L; K Siddiqi, Arsalan; Liu, Fang; Manohar, Nivedh; Cho, Sang Hyun [Nuclear and Radiological Engineering and Medical Physics Programs, Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)], E-mail: scho@gatech.edu

    2010-02-07

    A conventional x-ray fluorescence computed tomography (XFCT) technique requires monochromatic synchrotron x-rays to simultaneously determine the spatial distribution and concentration of various elements such as metals in a sample. However, the synchrotron-based XFCT technique appears to be unsuitable for in vivo imaging under a typical laboratory setting. In this study we demonstrated, for the first time to our knowledge, the possibility of performing XFCT imaging of a small animal-sized object containing gold nanoparticles (GNPs) at relatively low concentrations using polychromatic diagnostic energy range x-rays. Specifically, we created a phantom made of polymethyl methacrylate plastic containing two cylindrical columns filled with saline solution at 1 and 2 wt% GNPs, respectively, mimicking tumors/organs within a small animal. XFCT scanning of the phantom was then performed using microfocus 110 kVp x-ray beam and cadmium telluride (CdTe) x-ray detector under a pencil beam geometry after proper filtering of the x-ray beam and collimation of the detector. The reconstructed images clearly identified the locations of the two GNP-filled columns with different contrast levels directly proportional to gold concentration levels. On the other hand, the current pencil-beam implementation of XFCT is not yet practical for routine in vivo imaging tasks with GNPs, especially in terms of scanning time. Nevertheless, with the use of multiple detectors and a limited number of projections, it may still be used to image some objects smaller than the current phantom size. The current investigation suggests several modification strategies of the current XFCT setup, such as the adoption of the quasi-monochromatic cone/fan x-ray beam and XFCT-specific spatial filters or pinhole detector collimators, in order to establish the ultimate feasibility of a bench-top XFCT system for GNP-based preclinical molecular imaging applications.

  13. X-ray fluorescence computed tomography (XFCT) imaging of gold nanoparticle-loaded objects using 110 kVp x-rays.

    Science.gov (United States)

    Cheong, Seong-Kyun; Jones, Bernard L; Siddiqi, Arsalan K; Liu, Fang; Manohar, Nivedh; Cho, Sang Hyun

    2010-02-07

    A conventional x-ray fluorescence computed tomography (XFCT) technique requires monochromatic synchrotron x-rays to simultaneously determine the spatial distribution and concentration of various elements such as metals in a sample. However, the synchrotron-based XFCT technique appears to be unsuitable for in vivo imaging under a typical laboratory setting. In this study we demonstrated, for the first time to our knowledge, the possibility of performing XFCT imaging of a small animal-sized object containing gold nanoparticles (GNPs) at relatively low concentrations using polychromatic diagnostic energy range x-rays. Specifically, we created a phantom made of polymethyl methacrylate plastic containing two cylindrical columns filled with saline solution at 1 and 2 wt% GNPs, respectively, mimicking tumors/organs within a small animal. XFCT scanning of the phantom was then performed using microfocus 110 kVp x-ray beam and cadmium telluride (CdTe) x-ray detector under a pencil beam geometry after proper filtering of the x-ray beam and collimation of the detector. The reconstructed images clearly identified the locations of the two GNP-filled columns with different contrast levels directly proportional to gold concentration levels. On the other hand, the current pencil-beam implementation of XFCT is not yet practical for routine in vivo imaging tasks with GNPs, especially in terms of scanning time. Nevertheless, with the use of multiple detectors and a limited number of projections, it may still be used to image some objects smaller than the current phantom size. The current investigation suggests several modification strategies of the current XFCT setup, such as the adoption of the quasi-monochromatic cone/fan x-ray beam and XFCT-specific spatial filters or pinhole detector collimators, in order to establish the ultimate feasibility of a bench-top XFCT system for GNP-based preclinical molecular imaging applications.

  14. New developments of X-ray fluorescence imaging techniques in laboratory

    Science.gov (United States)

    Tsuji, Kouichi; Matsuno, Tsuyoshi; Takimoto, Yuki; Yamanashi, Masaki; Kometani, Noritsugu; Sasaki, Yuji C.; Hasegawa, Takeshi; Kato, Shuichi; Yamada, Takashi; Shoji, Takashi; Kawahara, Naoki

    2015-11-01

    X-ray fluorescence (XRF) analysis is a well-established analytical technique with a long research history. Many applications have been reported in various fields, such as in the environmental, archeological, biological, and forensic sciences as well as in industry. This is because XRF has a unique advantage of being a nondestructive analytical tool with good precision for quantitative analysis. Recent advances in XRF analysis have been realized by the development of new x-ray optics and x-ray detectors. Advanced x-ray focusing optics enables the making of a micro x-ray beam, leading to micro-XRF analysis and XRF imaging. A confocal micro-XRF technique has been applied for the visualization of elemental distributions inside the samples. This technique was applied for liquid samples and for monitoring chemical reactions such as the metal corrosion of steel samples in the NaCl solutions. In addition, a principal component analysis was applied for reducing the background intensity in XRF spectra obtained during XRF mapping, leading to improved spatial resolution of confocal micro-XRF images. In parallel, the authors have proposed a wavelength dispersive XRF (WD-XRF) imaging spectrometer for a fast elemental imaging. A new two dimensional x-ray detector, the Pilatus detector was applied for WD-XRF imaging. Fast XRF imaging in 1 s or even less was demonstrated for Euro coins and industrial samples. In this review paper, these recent advances in laboratory-based XRF imaging, especially in a laboratory setting, will be introduced.

  15. Probing symmetry and symmetry breaking in resonant soft-x-ray fluorescence spectra of molecules

    Energy Technology Data Exchange (ETDEWEB)

    Glans, P.; Gunnelin, K.; Guo, J. [Uppsala Univ. (Sweden)] [and others

    1997-04-01

    Conventional non-resonant soft X-ray emission brings about information about electronic structure through its symmetry and polarization selectivity, the character of which is governed by simple dipole rules. For centro-symmetric molecules with the emitting atom at the inversion center these rules lead to selective emission through the required parity change. For the more common classes of molecules which have lower symmetry or for systems with degenerate core orbitals (delocalized over identical sites), it is merely the local symmetry selectivity that provides a probe of the local atomic orbital contribution to the molecular orbital. For instance, in X-ray spectra of first row species the intensities essentially map the p-density at each particular atomic site, and, in a molecular orbital picture, the contribution of the local p-type atomic orbitals in the LCAO description of the molecular orbitals. The situation is different for resonant X-ray fluorescence spectra. Here strict parity and symmetry selectivity gives rise to a strong frequency dependence for all molecules with an element of symmetry. In addition to symmetry selectivity the strong frequency dependence of resonant X-ray emission is caused by the interplay between the shape of a narrow X-ray excitation energy function and the lifetime and vibrational broadenings of the resonantly excited core states. This interplay leads to various observable effects, such as linear dispersion, resonance narrowing and emission line (Stokes) doubling. Also from the point of view of polarization selectivity, the resonantly excited X-ray spectra are much more informative than the corresponding non-resonant spectra. Examples are presented for nitrogen, oxygen, and carbon dioxide molecules.

  16. Guest–Host Interactions Investigated by Time-Resolved X-ray Spectroscopies and Scattering at MHz Rates

    DEFF Research Database (Denmark)

    Haldrup, Martin Kristoffer; Vanko, G.; Gawelda, W.

    2012-01-01

    We have studied the photoinduced low spin (LS) to high spin (HS) conversion of [Fe(bipy)3]2+ in aqueous solution. In a laser pump/X-ray probe synchrotron setup permitting simultaneous, time-resolved X-ray diffuse scattering (XDS) and X-ray spectroscopic measurements at a 3.26 MHz repetition rate...... lifetime, allowing the detection of an ultrafast change in bulk solvent density. An analysis approach directly utilizing the spectroscopic data in the XDS analysis effectively reduces the number of free parameters, and both combined permit extraction of information about the ultrafast structural dynamics...

  17. Macro and micro full field x-ray fluorescence with an X-ray pinhole camera presenting high energy and high spatial resolution.

    Science.gov (United States)

    Romano, Francesco Paolo; Caliri, Claudia; Cosentino, Luigi; Gammino, Santo; Giuntini, Lorenzo; Mascali, David; Neri, Lorenzo; Pappalardo, Lighea; Rizzo, Francesca; Taccetti, Francesco

    2014-11-01

    This work describes a tabletop (50 cm × 25 cm × 25 cm) full field X-ray pinhole camera (FF-XPC) presenting high energy- and high spatial-resolution. The FF-XPC consists of a conventional charge-coupled device (CCD) detector coupled, in a coaxial geometry, to a pinhole collimator of small diameter. The X-ray fluorescence (XRF) is induced on the samples with an external low-power X-ray tube. The use of the CCD as an energy dispersive X-ray detector was obtained by adopting a multi-image acquisition in single photon counting and by developing a processing algorithm to be applied in real-time to each of the acquired image-frames. This approach allowed the measurement of X-ray spectra with an energy resolution down to 133 eV at the reference value of 5.9 keV. The detection of the X-ray fluorescence through the pinhole-collimator allowed the two-dimensional elemental mapping of the irradiated samples. Two magnifications (M), determined by the relative sample-pinhole-CCD distances, are used in the present setup. A low value of M (equal to 0.35×) allows the macro-FF-XRF of large area samples (up to 4 × 4 cm(2)) with a spatial resolution down to 140 μm; a large magnification (M equal to 6×) is used for the micro-FF-XRF of small area samples (2.5 × 2.5 mm(2)) with a spatial resolution down to 30 μm.

  18. Beer analysis by synchrotron radiation total reflection X-ray fluorescence (SR-TXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Recursos Hidricos]. E-mail: silvana@fec.unicamp.br; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear]. E-mail: virgilio@cena.usp.br; Zucchi, Orgheda L.D.A. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas de Ribeirao Preto]. E-mail: olzucchi@fcfrp.usp.br

    2005-07-01

    In this work the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian Legislation and the nutritive values established by National Agricultural Library (NAL). The measurements were performed at the X-ray Fluorescence Beamline at Synchrotron Light Source Laboratory, in Campinas, Sao Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 {mu}L of sample beers containing just an internal standard, used to correct geometry effects, were analyzed without any pre-treatment. The measuring time was 100 s and the detection limits obtained varied from 1{mu}g.L{sup -1} for Mn and Fe to 15{mu}g.L{sup -1} for P. (author)

  19. Determination of catalyst metal residues in polymers by X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Bichinho, Katia M. [CIENTEC-Fundacao de Ciencia e Tecnologia, Rua Washington Luiz, 675, Porto Alegre, 90010-460 (Brazil); Pires, Gilvan Pozzobon [Instituto de Quimica, Universidade Federal do Rio Grande do Sul (UFRGS) Avenida Bento Goncalves 9500, Porto Alegre, 91501-970 (Brazil); Stedile, Fernanda C. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul (UFRGS) Avenida Bento Goncalves 9500, Porto Alegre, 91501-970 (Brazil); Santos, Joao Henrique Z. dos [Instituto de Quimica, Universidade Federal do Rio Grande do Sul (UFRGS) Avenida Bento Goncalves 9500, Porto Alegre, 91501-970 (Brazil)]. E-mail: jhzds@iq.ufrgs.br; Wolf, Carlos Rodolfo [Ipiranga Petroquimica S.A., Departamento de Desenvolvimento de Produto, Polo Petroquimico do Sul, BR 386, km 419, Triunfo, CEP 95853-000 (Brazil)

    2005-06-30

    Commercial polyethylenes produced by Ziegler-Natta, Philips and metallocene technology were analyzed by X-ray fluorescence spectroscopy. Synthetic standards using wax matrix was shown to be suitable for the calibration curve in comparison to those prepared by milling and grinding virgin polymer mixed with standard metal oxide as matrix. The detection limits obtained for the studied metal in the different polymers were: 12 mg kg{sup -1} for Mg, 0.8 mg kg{sup -1} for Ti, 1.6 mg kg{sup -1} for Cr, 1.2 mg kg{sup -1} for Zr and 1.9 mg kg{sup -1} for V. For comparative reasons, the determination of residual metal content by Rutherford backscattering spectrometry (RBS) and total-reflection X-ray fluorescence spectrometry (TXRF) is also discussed.

  20. Application of the Total Reflection X-ray Fluorescence technique to trace elements determination in tobacco

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, T. [National University of Mexico, Faculty of Chemistry, Building D, CU (O4510) Mexico, D.F. Mexico (Mexico)], E-mail: tmc@servidor.unam.mx; Lartigue, J. [National University of Mexico, Faculty of Chemistry, Building D, CU (O4510) Mexico, D.F. Mexico (Mexico); Zarazua, G.; Avila-Perez, P. [National Institute of Nuclear Research. Carr. Mexico-Toluca Km 36.5, (52045) Salazar, Ocoyoacac, Edo. de Mexico (Mexico); Navarrete, M. [National University of Mexico, Faculty of Chemistry, Building D, CU (O4510) Mexico, D.F. Mexico (Mexico); Tejeda, S. [National Institute of Nuclear Research. Carr. Mexico-Toluca Km 36.5, (52045) Salazar, Ocoyoacac, Edo. de Mexico (Mexico)

    2008-12-15

    Many studies have identified an important number of toxic elements along with organic carcinogen molecules and radioactive isotopes in tobacco. In this work we have analyzed by Total Reflection X-Ray Fluorescence 9 brands of cigarettes being manufactured and distributed in the Mexican market. Two National Institute of Standards and Technology standards and a blank were equally treated at the same time. Results show the presence of some toxic elements such as Pb and Ni. These results are compared with available data for some foreign brands, while their implications for health are discussed. It can be confirmed that the Total Reflection X-Ray Fluorescence method provides precise (reproducible) and accuracy (trueness) data for 15 elements concentration in tobacco samples.

  1. Elemental mapping of biofortified wheat grains using micro X-ray fluorescence

    Science.gov (United States)

    Ramos, I.; Pataco, I. M.; Mourinho, M. P.; Lidon, F.; Reboredo, F.; Pessoa, M. F.; Carvalho, M. L.; Santos, J. P.; Guerra, M.

    2016-06-01

    Micro X-ray fluorescence has been used to obtain elemental maps of biofortified wheat grains. Two varieties of wheat were used in the study, Triticum aestivum L. and Triticum durum desf. Two treatments, with different nutrient concentration, were applied to the plants during the whole plant growth cycle. From the obtained elemental maps it was possible to extract information regarding the plant's physiological processes under the biofortification procedures. Both macro and micronutrients were mapped, providing useful insight into the posterior food processing mechanisms of this biofortified staple food. We have also shown that these kind of studies can now be performed with laboratory benchtop apparatus, rather than using synchrotron radiation, increasing the overall attractiveness of micro X-ray fluorescence in the study of highly heterogeneous biological samples.

  2. Application of X-Ray Fluorescence Analysis in Investigations of Historical Monuments

    Directory of Open Access Journals (Sweden)

    T. Čechák

    2005-01-01

    Full Text Available Nuclear techniques and other techniques using ionising radiation represent a valuable tool in non-destructive diagnostics applied to archaeological finds and objects of arts, namely for determining the composition of materials used in the production of artefacts. X-ray fluorescence analysis, both in its energy form and in its wave dispersive form, is one of the most widespread methods using ionising radiation to study the elemental composition of materials. It is frequently used for studies of various cultural and historic relicts and objects of art. This work summarizes the authors’ experience with X-ray fluorescence analysis in investigating historical frescos namely by means of portable provide spectroscopic devices. The results of these measurements information on the composition of the pigments, enable the comparison of processes used in the fabrication of pigments by individual artists, and in many cases offer information on how to repair the damaged parts. 

  3. X-ray fluorescence/Auger-electron coincidence spectroscopy of vacancy cascades in atomic argon

    Energy Technology Data Exchange (ETDEWEB)

    Arp, U. [National Inst. of Standards and Technology, Gaithersburg, MD (United States). Electron and Optical Physics Div.; LeBrun, T.; Southworth, S.H.; Jung, M. [Argonne National Lab., IL (United States). Physics Div.; MacDonald, M.A. [E.P.S.R.C. Daresbury Lab., Warrington (United Kingdom)

    1996-12-01

    Argon L{sub 2.3}-M{sub 2.3}M{sub 2.3} Auger-electron spectra were measured in coincidence with K{alpha} fluorescent x-rays in studies of Ar K-shell vacancy decays at several photon energies above the K-threshold and on the 1s-4p resonance in atomic argon. The complex spectra recorded by conventional electron spectroscopy are greatly simplified when recorded in coincidence with fluorescent x-rays, allowing a more detailed analysis of the vacancy cascade process. The resulting coincidence spectra are compared with Hartree-Fock calculations which include shake-up transitions in the resonant case. Small energy shifts of the coincidence electron spectra are attributed to post-collision interaction with 1s photoelectrons.

  4. Time-Resolved Soft X-ray Diffraction Reveals Transient Structural Distortions of Ternary Liquid Crystals

    Directory of Open Access Journals (Sweden)

    Klaus Mann

    2009-11-01

    Full Text Available Home-based soft X-ray time-resolved scattering experiments with nanosecond time resolution (10 ns and nanometer spatial resolution were carried out at a table top soft X-ray plasma source (2.2–5.2 nm. The investigated system was the lyotropic liquid crystal C16E7/paraffin/glycerol/formamide/IR 5. Usually, major changes in physical, chemical, and/or optical properties of the sample occur as a result of structural changes and shrinking morphology. Here, these effects occur as a consequence of the energy absorption in the sample upon optical laser excitation in the IR regime. The liquid crystal shows changes in the structural response within few hundred nanoseconds showing a time decay of 182 ns. A decrease of the Bragg peak diffracted intensity of 30% and a coherent macroscopic movement of the Bragg reflection are found as a response to the optical pump. The Bragg reflection movement is established to be isotropic and diffusion controlled (1 μs. Structural processes are analyzed in the Patterson analysis framework of the time-varying diffraction peaks revealing that the inter-lamellar distance increases by 2.7 Å resulting in an elongation of the coherently expanding lamella crystallite. The present studies emphasize the possibility of applying TR-SXRD techniques for studying the mechanical dynamics of nanosystems.

  5. Time-resolved soft X-ray diffraction reveals transient structural distortions of ternary liquid crystals.

    Science.gov (United States)

    Quevedo, Wilson; Peth, Christian; Busse, Gerhard; Scholz, Mirko; Mann, Klaus; Techert, Simone

    2009-11-04

    Home-based soft X-ray time-resolved scattering experiments with nanosecond time resolution (10 ns) and nanometer spatial resolution were carried out at a table top soft X-ray plasma source (2.2-5.2 nm). The investigated system was the lyotropic liquid crystal C(16)E(7)/paraffin/glycerol/formamide/IR 5. Usually, major changes in physical, chemical, and/or optical properties of the sample occur as a result of structural changes and shrinking morphology. Here, these effects occur as a consequence of the energy absorption in the sample upon optical laser excitation in the IR regime. The liquid crystal shows changes in the structural response within few hundred nanoseconds showing a time decay of 182 ns. A decrease of the Bragg peak diffracted intensity of 30% and a coherent macroscopic movement of the Bragg reflection are found as a response to the optical pump. The Bragg reflection movement is established to be isotropic and diffusion controlled (1 micros). Structural processes are analyzed in the Patterson analysis framework of the time-varying diffraction peaks revealing that the inter-lamellar distance increases by 2.7 A resulting in an elongation of the coherently expanding lamella crystallite. The present studies emphasize the possibility of applying TR-SXRD techniques for studying the mechanical dynamics of nanosystems.

  6. Evaluation of Portable X-Ray Fluorescence (XRF) Analyzer for Zirconium-Thickness Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Glenn Moore

    2013-09-01

    This Technical Evaluation Report provides details of preliminary testing/experiments performed using a handheld X-ray fluorescence analyzer. The analyzer will be utilized in upcoming fuel-foil-rolling optimization studies at the INL. The studies are being performed in support of DOE’s Office of Global Threat Reduction -- Reactor Conversion Subprogram. Details of the equipment used, operating parameters, and measurement results are provided in this report.

  7. A gas microstrip X-ray detector for soft energy fluorescence EXAFS

    CERN Document Server

    Smith, A D; Derbyshire, G E; Duxbury, D M; Lipp, J; Spill, E J; Stephenson, R

    2001-01-01

    Gas microstrip detectors have been previously developed by the particle physics community, where their robustness, compactness and high counting speed have been recognised. These features are particularly attractive to synchrotron radiation use. In this paper, we describe a gas microstrip detector employing multi-element readout and specifically developed for high count rate fluorescence EXAFS at soft X-ray energies below 4 keV.

  8. Determination of Fission Products in Irradiated Fuel by X-Ray Fluorescence

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg; Als-Nielsen, Jens Aage; Andersen, Niels Hessel

    X-ray fluorescence i s a well e s t a b l i s h e d analytical tool for measuring elemental composition of fairly large (~ 5 cm2) "cold" samples. A version of t h i s technique has been developed for a n a l y s i s of radial d i s t r i b u t i o n of f i s s i o n products Xe, Cs and Ba in irra...

  9. X-Ray Fluorescence Spectroscopy for Analysis of Explosive-Related Materials and Unknowns

    Science.gov (United States)

    2017-08-01

    common thin-film materials . Table B-1. Compatibility of Support Films for Wavelength Dispersive XRF Samples Sample Component Etnom...X-RAY FLUORESCENCE SPECTROSCOPY FOR ANALYSIS OF EXPLOSIVE-RELATED MATERIALS AND UNKNOWNS ECBC-TR-1455...of Explosive-Related Materials and Unknowns 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Valdes, Erica R

  10. In-lab X-ray fluorescence and diffraction techniques for pathological calcifications

    OpenAIRE

    Rouzière, Stéphan; Bazin, Dominique; Daudon, Michel

    2016-01-01

    International audience; If imaging by physical methods is probably the best well-known link between physics and medicine, other ways such as X-ray fluorescence and diffraction techniques give significant information to clinicians. In this contribution, we would like to assess different results obtained through such techniques on three main problems in urology namely Randall's plaque, brushite kidney stones and phase conversion between weddellite and whewellite. Randall's plaque is a mineral d...

  11. Fluorescence x-ray standing wave study on (AlAs)(GaAs) superlattices

    CERN Document Server

    Lessmann, A; Munkholm, A; Schuster, M; Riechert, H; Materlik, G

    1999-01-01

    X-ray standing waves (XSW) were used to investigate the structure of molecular beam epitaxy (MBE) grown (AlAs) sub 3 (GaAs) sub 7 short-period superlattices (SPSL). The modulation of the Al K, As L, and Ga L x-ray fluorescence induced by XSW was measured at the zero-order superlattice (SL) satellite (AlAs)(GaAs)(004,0) and the GaAs(004) substrate Bragg reflection. From the shape of the fluorescence yield modulations and the diffraction pattern, a model of the interfaces is derived by comparing the experimental data with dynamical calculations of the x-ray wave field distribution and reflectivity. A straightforward analysis of the fluorescence measurements at the SL satellite shows that in AlAs layers a high crystalline order is established, whereas in GaAs layers a fraction of the Ga and As atoms is not on ideal lattice sites, but is displaced towards the substrate. The data can be explained by a model in which, at each AlAs/GaAs interface of the GaAs layers, two Ga atom planes are displaced by 0.035 nm and 0...

  12. X-ray fluorescence analysis of ancient and medieval brass artifacts from south Moravia

    Energy Technology Data Exchange (ETDEWEB)

    Hlozek, M. [Methodical Centre of Conservation-Technical Museum in Brno, Purkynova 105, 612 00 Brno (Czech Republic); Komoroczy, B. [Institute of Archeology of the Academy of Science of the Czech Republic, Kralovopolska 147, 612 00 Brno (Czech Republic); Trojek, T., E-mail: tomas.trojek@fjfi.cvut.cz [Department of Dosimetry and Application of Ionizing Radiation, Czech Technical University in Prague, Brehova 7, 115 19 Praha 1 (Czech Republic)

    2012-07-15

    This paper deals with an investigation of archeological finds using X-ray fluorescence analysis and microanalysis. The main aim of the investigation was to prove the production of brass in the South Moravian Region (part of the Czech Republic) in former times. The probable brass production technology is described. Various objects dating back to Antiquity and to the Middle Ages were investigated using two X-ray fluorescence systems, and the results of the analyses are discussed. The measurements showed, e.g., that fragments of Roman scale armor and a belt fitting dating back to Antiquity were made of brass. Brass was also identified on the surfaces of various ancient and medieval molds and melting pots. - Highlights: Black-Right-Pointing-Pointer Semiquantitative X-ray fluorescence analysis of archeological finds. Black-Right-Pointing-Pointer Two different gilding techniques of a brass belt terminal found in Brno. Black-Right-Pointing-Pointer Use of brass before the Great Moravian period. Black-Right-Pointing-Pointer Evidence of brass casting in the 12th century in Brno.

  13. Development of suitable plastic standards for X-ray fluorescence analysis

    Science.gov (United States)

    Mans, Christian; Hanning, Stephanie; Simons, Christoph; Wegner, Anne; Janβen, Anton; Kreyenschmidt, Martin

    2007-02-01

    For the adoption of the EU directive "Restriction on use of certain Hazardous Substances" and "Waste Electrical and Electronic Equipment" using X-ray fluorescence analysis suitable standard materials are required. Plastic standards based on acrylonitrile-butadiene-styrene terpolymer, containing the regulated elements Br, Cd, Cr, Hg and Pb were developed and produced as granulates and solid bodies. The calibration materials were not generated as a dilution from one master batch but rather the element concentrations were distributed over nine independent calibration samples. This was necessary to enable inter-elemental corrections and empirical constant mass absorption coefficients. The produced standard materials are characterized by a homogenous element distribution, which is more than sufficient for X-ray fluorescence analysis. Concentrations for all elements except for Br could be determined by Inductively Coupled Plasma Atomic Emission Spectroscopy after microwave assisted digestion. The concentration of Br was determined by use of Neutron Activation Analysis at Hahn-Meitner-Institute in Berlin, Germany. The correlation of the X-ray fluorescence analysis measurements with the values determined using Inductively Coupled Plasma Atomic Emission Spectroscopy and Neutron Activation Analysis showed a very good linearity.

  14. Fluorescence x-ray standing wave study on (AlAs)(GaAs) superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Lessmann, A.; Brennan, S.; Munkholm, A. [Stanford Synchrotron Radiation Laboratory SSRL/SLAC, Menlo Park, CA (United States); Schuster, M.; Riechert, H. [Siemens AG, Corporate Technology, Munich (Germany); Materlik, G. [Hamburger Synchrotronstrahlungslabor HASYLAB/DESY, Hamburg (Germany)

    1999-05-21

    X-ray standing waves (XSW) were used to investigate the structure of molecular beam epitaxy (MBE) grown (AlAs){sub 3}(GaAs){sub 7} short-period superlattices (SPSL). The modulation of the Al K, As L, and Ga L x-ray fluorescence induced by XSW was measured at the zero-order superlattice (SL) satellite (AlAs)(GaAs)(004,0) and the GaAs(004) substrate Bragg reflection. From the shape of the fluorescence yield modulations and the diffraction pattern, a model of the interfaces is derived by comparing the experimental data with dynamical calculations of the x-ray wave field distribution and reflectivity. A straightforward analysis of the fluorescence measurements at the SL satellite shows that in AlAs layers a high crystalline order is established, whereas in GaAs layers a fraction of the Ga and As atoms is not on ideal lattice sites, but is displaced towards the substrate. The data can be explained by a model in which, at each AlAs/GaAs interface of the GaAs layers, two Ga atom planes are displaced by 0.035 nm and 0.008 nm and one As atom plane by 0.023 nm. The displacements within the GaAs layers exhibit a mirror symmetry with respect to the centre of each layer. (author)

  15. A method of measuring gold nanoparticle concentrations by x-ray fluorescence for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Wu Di; Li Yuhua; Wong, Molly D.; Liu Hong [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)

    2013-05-15

    Purpose: This paper reports a technique that enables the quantitative determination of the concentration of gold nanoparticles (GNPs) through the accurate detection of their fluorescence radiation in the diagnostic x-ray spectrum. Methods: Experimentally, x-ray fluorescence spectra of 1.9 and 15 nm GNP solutions are measured using an x-ray spectrometer, individually and within chicken breast tissue samples. An optimal combination of excitation and emission filters is determined to segregate the fluorescence spectra at 66.99 and 68.80 keV from the background scattering. A roadmap method is developed that subtracts the scattered radiation (acquired before the insertion of GNP solutions) from the signal radiation acquired after the GNP solutions are inserted. Results: The methods effectively minimize the background scattering in the spectrum measurements, showing linear relationships between GNP solutions from 0.1% to 10% weight concentration and from 0.1% to 1.0% weight concentration inside a chicken breast tissue sample. Conclusions: The investigation demonstrated the potential of imaging gold nanoparticles quantitatively in vivo for in-tissue studies, but future studies will be needed to investigate the ability to apply this method to clinical applications.

  16. Portable apparatus for in situ x-ray diffraction and fluorescence analyses of artworks.

    Science.gov (United States)

    Eveno, Myriam; Moignard, Brice; Castaing, Jacques

    2011-10-01

    A portable X-ray fluorescence/X-ray diffraction (XRF/XRD) system for artwork studies has been designed constructed and tested. It is based on Debye Scherrer XRD in reflection that takes advantage of many recent improvements in the handling of X-rays (polycapillary optics; advanced two-dimensional detection). The apparatus is based on a copper anode air cooled X-ray source, and the XRD analysis is performed on a 5-20 μm thick layer from the object surface. Energy dispersive XRF elemental analysis can be performed at the same point as XRD, giving elemental compositions that support the interpretation of XRD diagrams. XRF and XRD analyses were tested to explore the quality and the limits of the analytical technique. The XRD diagrams are comparable in quality with diagrams obtained with conventional laboratory equipment. The mineral identification of materials in artwork is routinely performed with the portable XRF-XRD system. Examples are given for ceramic glazes containing crystals and for paintings where the determination of pigments is still a challenge for nondestructive analysis. For instance, lead compounds that provide a variety of color pigments can be easily identified as well as a pigment such as lapis lazuli that is difficult to identify by XRF alone. More than 70 works of art have been studied in situ in museums, monuments, etc. In addition to ceramics and paintings, these works include bronzes, manuscripts, etc., which permit improvement in the comprehension of ancient artistic techniques.

  17. LabVIEW control software for scanning micro-beam X-ray fluorescence spectrometer.

    Science.gov (United States)

    Wrobel, Pawel; Czyzycki, Mateusz; Furman, Leszek; Kolasinski, Krzysztof; Lankosz, Marek; Mrenca, Alina; Samek, Lucyna; Wegrzynek, Dariusz

    2012-05-15

    Confocal micro-beam X-ray fluorescence microscope was constructed. The system was assembled from commercially available components - a low power X-ray tube source, polycapillary X-ray optics and silicon drift detector - controlled by an in-house developed LabVIEW software. A video camera coupled to optical microscope was utilized to display the area excited by X-ray beam. The camera image calibration and scan area definition software were also based entirely on LabVIEW code. Presently, the main area of application of the newly constructed spectrometer is 2-dimensional mapping of element distribution in environmental, biological and geological samples with micrometer spatial resolution. The hardware and the developed software can already handle volumetric 3-D confocal scans. In this work, a front panel graphical user interface as well as communication protocols between hardware components were described. Two applications of the spectrometer, to homogeneity testing of titanium layers and to imaging of various types of grains in air particulate matter collected on membrane filters, were presented.

  18. A novel approach to angular-resolved X-ray photoelectron spectroscopy depth-profiling

    Energy Technology Data Exchange (ETDEWEB)

    Stanchev, A.; Ignatova, V.; Ghelev, Ch. E-mail: chghelev@ie.bas.bg

    2000-05-02

    The angular-resolved-X-ray photoelectron spectroscopy (AR-XPS) technique is chosen to investigate the O redistribution on the surface of yttria-stabilized ZrO{sub 2} crystals during 10 keV He{sup +} ion bombardment. The data processing is performed by means of a newly-developed version of the 'Box-car' function method. An energy correction of the inelastic mean free paths (IMFP) of the elements present is performed and the elements peak areas are normalized with respect to surface carbon layer. An algorithm is described, which is tested and applied to the angular-dependent XPS data, and the true elements' depth-profiles are thus obtained.

  19. Resolving the Crab Nebula with Direct Hard X-Ray Imaging

    Science.gov (United States)

    Swartz, Douglas A.; Ramsey, Brian D.; Tennant, Allyn F.; Dietz, Kurtis L.; Apple, Jeff A.; Gaskin, Jessica A.; Weisskopf, Martin

    2008-01-01

    We report the first direct hard (25--60 keV) X-ray imaging observation of the Crab Nebula that resolves structure to approximately 0.25 pc. The observation was performed over a 1.4 hour period during a balloon flight from Ft. Sumner, NM, on 2007 May 27. The source was detected in the energy band above the atmospheric cutoff at approx.25 keV and below the mirror graze angle cutoff at approx.60 keV. The image shows elongation about 25 degrees E of N in the direction along the plane of the torus (and perpendicular to the jet axis) with a slight surface-brightness enhancement NE of the pulsar. The spectrum within a 1.7 arcminute radius region centered on the Crab pulsar can be fitted with a Gamma=2 power law absorbed by an atmospheric column consistent with the balloon altitude at the time of observation.

  20. Time-resolved synchrotron radiation X-ray solution scattering study of DNA melting.

    Science.gov (United States)

    Puigdomenech, J; Perez-Grau, L; Porta, J; Vega, M C; Sicre, P; Koch, M H

    1989-09-01

    Time resolved x-ray solution scattering measurements were made during thermal denaturation of DNA from various sources in the temperature range of 20-90 degrees C. Preliminary results on the influence of fragment length, ionic strength, and origin of the DNA on the time course of the scattering are described. Interpretation is based on model calculations of the scattering patterns. The results indicate that, for long DNA fragments at very low ionic strength, the melting process is a continuous phenomenon over the whole temperature range. It is accompanied by a progressive decrease of the radius of gyration of the cross section and of the mass per unit length. For short fragments of 146 base pair nucleosomal core DNA, stiffening of the DNA appears to precede a sharp melting transition.

  1. Energy resolving power of transition-edge X-ray microcalorimeters

    NARCIS (Netherlands)

    Bergmann Tiest, W.M.

    2004-01-01

    This thesis describes the development and device physics of an X-ray microcalorimeter. This is a device for measuring the energy of X-rays. The microcalorimeter measures the temperature increase that is the result of the absorption of an X-ray photon. Combined into an array, the microcalorimeter can

  2. Effect of regolith on planetary X-ray fluorescence spectroscopy: laboratory and numerical studies

    Science.gov (United States)

    Naranen, Jyri; Carpenter, James; Parviainen, Hannu; Muinonen, Karri

    Fluorescent X-rays from the surfaces of airless planetary bodies in the inner solar system have been measured by instruments on several spacecraft. X-ray emission follows photoionisation by incident solar X-rays and charged particles and reveals the elemental composition of the surface. Analyses of X-ray spectra obtained by orbiting spacecraft, use the relative intensities of elemental emission lines (e.g., Ca/Si, Fe/Si) to determine the geochemistry of the target body. Historically, the analysis of X-ray spectra has assumed that surfaces can be considered as homogeneous plane-parallel media. It has been shown, however, that relative line intensities are affected by the physical properties of the target surface (e.g. particle size distribution and packing density of the regolith) and the viewing and illumination geometry of observations. We describe experimental investigations into the effects of regolith properties on the line ratios measured by a nadir pointing (emergence angle 0° ) orbiting instrument, with with solar illumination angles in the range 25-75° from zenith. The planetary regolith analogue used in these experiments was a terrestrial, olivine rich basalt, which has been used by previous authors as an analogue to the lunar maria. The basalt samples were ground to powder and sieved to discriminate particles in the ranges, pellets. The separation of particles with different sizes allows some determination of the effects due to changes in particle size. All measurements were made at pressures of less than 0.5 mbar to prevent absorption of fluorescent X-rays in air. The relative fluorescent line ratios of several major rock forming elements (K, Ca, Ti, Si) were measured. We find that for measurements made in a "nadir" pointing geometry, the measured spectrum becomes increasingly hard as illumination angle increases (i.e. X-ray lines at higher energies are enhanced relative to those at lower energies). Some hardening of spectra is predicted by the

  3. Time-resolved and in-situ X-ray scattering methods beyond photoactivation: Utilizing high-flux X-ray sources for the study of ubiquitous non-photoactive proteins.

    Science.gov (United States)

    Jain, Rohit; Techert, Simone

    2016-01-01

    X-ray scattering technique, comprising of small-angle/wide-angle X-ray scattering (SAXS/WAXS) techniques is increasingly used to characterize the structure and interactions of biological macromolecules and their complexes in solution. It is a method of choice to characterize the flexible, partially folded and unfolded protein systems. X-ray scattering is the last resort for proteins that cannot be investigated by crystallography or NMR and acts as a complementary technique with different biophysical techniques to answer challenging scientific questions. The marriage of the X-ray scattering technique with the fourth dimension "time" yields structural dynamics and kinetics information for protein motions in hierarchical timescales from picoseconds to days. The arrival of the high-flux X-ray beam at third generation synchrotron sources, exceptional X-ray optics, state-of-the-art detectors, upgradation of X-ray scattering beamlines with microfluidics devices and advanced X-ray scattering data analysis procedures are the important reasons behind the shining years of X-ray scattering technique. The best days of the X-ray scattering technique are on the horizon with the advent of the nanofocus X-ray scattering beamlines and fourth generation X-ray lightsources, i.e., free electron lasers (XFELs). Complementary to the photon-triggered time-resolved X-ray scattering techniques, we will present an overview of the time-resolved and in-situ X-ray scattering techniques for structural dynamics of ubiquitous non-photoactive proteins.

  4. Total reflection x-ray fluorescence: Determination of an optimum geometry

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Y.M. [Pohang Univ. of Science and Technology (Korea, Republic of); Chang, C.H.; Padmore, H.A. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Total reflection X-Ray Fluorescence (TXRF) is a widely used technique in which the normal trace element detection capability of hard x-ray fluorescence (XRF) is enhanced by use of an x-ray reflective substrate. TXRF is more sensitive than normal photon induced XRF due to the reduction of the substrate scattering and fluorescence signals. This reduction comes about because in total external reflection, the photon field only penetrates about 20 {angstrom} into the surface, instead of typically 50 {mu}m for a silicon substrate at normal incidence for 10 KeV photons. The technique is used in many fields of trace element analysis, and is widely used in the determination of metal impurity concentrations on and in the surface of silicon wafers. The Semiconductor Industry Association roadmap (SIA) indicates a need for wafer contamination detection at the 10{sup 7}atoms/cm{sup 2} level in the next few years. Current commercial systems using rotating anode x-ray sources presently routinely operate with a sensitivity level of around 10{sup 10} atoms/cm{sup 2} and this has led to interest in the use of synchrotron radiation to extend the sensitivity by three orders of magnitude. The pioneering work of Pianetta and co-workers at SSRL has clearly shown that this should be possible, using a fully optimized source and detector. The purpose of this work is to determine whether ALS would be a suitable source for this type of highly sensitive wafer TXRF. At first look it appears improbable as the SSRL work used a high flux multipole wiggler source, and it is clear that the detected fluorescence for relevant concentrations is small. In addition, SSRL operates at 3.0 GeV rather than 1.9 GeV, and is therefore more naturally suited to hard x-ray experiments. The aim of this work was therefore to establish a theoretical model for the scattering and fluorescence processes, so that one could predict the differences between alternative geometries and select an optimum configuration.

  5. Semi-empirical model for fluorescence lines evaluation in diagnostic x-ray beams.

    Science.gov (United States)

    Bontempi, Marco; Andreani, Lucia; Labanti, Claudio; Costa, Paulo Roberto; Rossi, Pier Luca; Baldazzi, Giuseppe

    2016-01-01

    Diagnostic x-ray beams are composed of bremsstrahlung and discrete fluorescence lines. The aim of this study is the development of an efficient model for the evaluation of the fluorescence lines. The most important electron ionization models are analyzed and implemented. The model results were compared with experimental data and with other independent spectra presented in the literature. The implemented peak models allow the discrimination between direct and indirect radiation emitted from tungsten anodes. The comparison with the independent literature spectra indicated a good agreement.

  6. Opportunities and challenges for time-resolved studies of protein structural dynamics at X-ray free-electron lasers.

    Science.gov (United States)

    Neutze, Richard

    2014-07-17

    X-ray free-electron lasers (XFELs) are revolutionary X-ray sources. Their time structure, providing X-ray pulses of a few tens of femtoseconds in duration; and their extreme peak brilliance, delivering approximately 10(12) X-ray photons per pulse and facilitating sub-micrometre focusing, distinguish XFEL sources from synchrotron radiation. In this opinion piece, I argue that these properties of XFEL radiation will facilitate new discoveries in life science. I reason that time-resolved serial femtosecond crystallography and time-resolved wide angle X-ray scattering are promising areas of scientific investigation that will be advanced by XFEL capabilities, allowing new scientific questions to be addressed that are not accessible using established methods at storage ring facilities. These questions include visualizing ultrafast protein structural dynamics on the femtosecond to picosecond time-scale, as well as time-resolved diffraction studies of non-cyclic reactions. I argue that these emerging opportunities will stimulate a renaissance of interest in time-resolved structural biochemistry.

  7. Opportunities and challenges for time-resolved studies of protein structural dynamics at X-ray free-electron lasers

    Science.gov (United States)

    Neutze, Richard

    2014-01-01

    X-ray free-electron lasers (XFELs) are revolutionary X-ray sources. Their time structure, providing X-ray pulses of a few tens of femtoseconds in duration; and their extreme peak brilliance, delivering approximately 1012 X-ray photons per pulse and facilitating sub-micrometre focusing, distinguish XFEL sources from synchrotron radiation. In this opinion piece, I argue that these properties of XFEL radiation will facilitate new discoveries in life science. I reason that time-resolved serial femtosecond crystallography and time-resolved wide angle X-ray scattering are promising areas of scientific investigation that will be advanced by XFEL capabilities, allowing new scientific questions to be addressed that are not accessible using established methods at storage ring facilities. These questions include visualizing ultrafast protein structural dynamics on the femtosecond to picosecond time-scale, as well as time-resolved diffraction studies of non-cyclic reactions. I argue that these emerging opportunities will stimulate a renaissance of interest in time-resolved structural biochemistry. PMID:24914150

  8. Time-resolved structural studies at synchrotrons and X-ray free electron lasers: opportunities and challenges

    Science.gov (United States)

    Neutze, Richard; Moffat, Keith

    2012-01-01

    X-ray free electron lasers (XFELs) are potentially revolutionary X-ray sources because of their very short pulse duration, extreme peak brilliance and high spatial coherence, features that distinguish them from today’s synchrotron sources. We review recent time-resolved Laue diffraction and time-resolved wide angle X-ray scattering (WAXS) studies at synchrotron sources, and initial static studies at XFELs. XFELs have the potential to transform the field of time-resolved structural biology, yet many challenges arise in devising and adapting hardware, experimental design and data analysis strategies to exploit their unusual properties. Despite these challenges, we are confident that XFEL sources are poised to shed new light on ultrafast protein reaction dynamics. PMID:23021004

  9. High-resolution soft X-ray beamline ADRESS at the Swiss Light Source for resonant inelastic X-ray scattering and angle-resolved photoelectron spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Strocov, V. N., E-mail: vladimir.strocov@psi.ch; Schmitt, T.; Flechsig, U.; Schmidt, T.; Imhof, A.; Chen, Q.; Raabe, J. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Betemps, R.; Zimoch, D.; Krempasky, J. [Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Wang, X. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Institut de Physique de la Matiére Condensé, Ecole Polytechnique Fédéderale de Lausanne (Switzerland); Grioni, M. [Institut de Physique de la Matiére Condensé, Ecole Polytechnique Fédéderale de Lausanne (Switzerland); Piazzalunga, A. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Patthey, L. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland)

    2010-09-01

    Concepts and technical realization of the high-resolution soft X-ray beamline ADRESS at the Swiss Light Source are described. Optimization of the optical scheme for high resolution and photon flux as well as diagnostics tools and alignment strategies are discussed. The concepts and technical realisation of the high-resolution soft X-ray beamline ADRESS operating in the energy range from 300 to 1600 eV and intended for resonant inelastic X-ray scattering (RIXS) and angle-resolved photoelectron spectroscopy (ARPES) are described. The photon source is an undulator of novel fixed-gap design where longitudinal movement of permanent magnetic arrays controls not only the light polarization (including circular and 0–180° rotatable linear polarizations) but also the energy without changing the gap. The beamline optics is based on the well established scheme of plane-grating monochromator operating in collimated light. The ultimate resolving power E/ΔE is above 33000 at 1 keV photon energy. The choice of blazed versus lamellar gratings and optimization of their profile parameters is described. Owing to glancing angles on the mirrors as well as optimized groove densities and profiles of the gratings, the beamline is capable of delivering high photon flux up to 1 × 10{sup 13} photons s{sup −1} (0.01% BW){sup −1} at 1 keV. Ellipsoidal refocusing optics used for the RIXS endstation demagnifies the vertical spot size down to 4 µm, which allows slitless operation and thus maximal transmission of the high-resolution RIXS spectrometer delivering E/ΔE > 11000 at 1 keV photon energy. Apart from the beamline optics, an overview of the control system is given, the diagnostics and software tools are described, and strategies used for the optical alignment are discussed. An introduction to the concepts and instrumental realisation of the ARPES and RIXS endstations is given.

  10. Monochromatic wavelength dispersive x-ray fluorescence providing sensitive and selective detection of uranium

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, George J [Los Alamos National Laboratory; Collins, Michael L [Los Alamos National Laboratory; Montoya, Velma M [Los Alamos National Laboratory; Chen, Zewu [XOS; Wei, Fuzhong [XOS

    2010-01-01

    Monochromatic wavelength dispersive X-ray fluorescence (MWDXRF) is a sensitive and selective method for elemental compositional analyses. The basis for this instrumental advance is the doubly curved crystal (DCC) optic. Previous work has demonstrated the feasibility of sensitive trace element detection for yttrium as a surrogate for curium in aqueous solutions. Additional measurements have demonstrated similar sensitivity in several different matrix environments which attests to the selectivity of the DCC optic as well as the capabilities of the MWDXRF concept. The objective of this effort is to develop an improved Pu characterization method for nuclear fuel reprocessing plants. The MWDXRF prototype instrument is the second step in a multi-year effort to achieve an improved Pu assay. This work will describe a prototype MWDXRF instrument designed for uranium detection and characterization. The prototype consists of an X-ray tube with a rhodium anode and a DCC excitation optic incorporated into the source. The DCC optic passes the RhK{alpha} line at 20.214 keV for monochromatic excitation of the sample. The source is capable of 50 W power at 50 kV and 1.0 mA operation. The x-ray emission from the sample is collected by a DCC optic set at the UL{alpha} line of 13.613 keV. The collection optic transmits the UL{alpha} x-rays to the silicon drift detector. The x-ray source, sample, collection optic and detector are all mounted on motion controlled stages for the critical alignment of these components. The sensitivity and selectivity of the instrument is obtained through the monochromatic excitation and the monochromatic detection. The prototype instrument performance has a demonstrated for sensitivity for uranium detection of around 2 ppm at the current state of development. Further improvement in sensitivity is expected with more detailed alignment.

  11. Monochromatic X-ray propagation in multi-Z media for imaging and diagnostics including Kα Resonance Fluorescence

    Science.gov (United States)

    Westphal, Maximillian; Lim, Sara; Nahar, Sultana; Pradhan, Anil

    2016-05-01

    Aimed at monochromatic X-ray imaging and therapy, broadband, monochromatic, and quasi-monochromatic X-ray sources and propagation through low and high-Z (HZ) media were studied with numerically and experimentally. Monte Carlo simulations were performed using the software package Geant4, and a new code Photx, to simulate X-ray image contrast, depth of penetration, and total attenuation. The data show that monochromatic and quasi-monochromatic X-rays achieve improved contrast at lower absorbed radiation doses compared to conventional broadband 120 kV or CT scans. Experimental quasi-monochromatic high-intensity laser-produced plasma sources and monochromatic synchrotron beam data are compared. Physical processes responsible for X-ray photoexcitation and absorption are numerically modelled, including a novel mechanism for accelerating Kα resonance fluorescence via twin monochromatic X-ray beam. Potential applications are medical diagnostics and high-Z material detection. Acknowledgement: Ohio Supercomputer Center, Columbus, OH.

  12. Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Sheftman, D.; Shafer, D.; Efimov, S.; Gruzinsky, K.; Gleizer, S.; Krasik, Ya. E. [Physics Department, Technion, Haifa 32000 (Israel)

    2012-10-15

    A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A {approx}4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

  13. Determination of minor and trace elements in kidney stones by x-ray fluorescence analysis

    Science.gov (United States)

    Srivastava, Anjali; Heisinger, Brianne J.; Sinha, Vaibhav; Lee, Hyong-Koo; Liu, Xin; Qu, Mingliang; Duan, Xinhui; Leng, Shuai; McCollough, Cynthia H.

    2014-03-01

    The determination of accurate material composition of a kidney stone is crucial for understanding the formation of the kidney stone as well as for preventive therapeutic strategies. Radiations probing instrumental activation analysis techniques are excellent tools for identification of involved materials present in the kidney stone. In particular, x-ray fluorescence (XRF) can be very useful for the determination of minor and trace materials in the kidney stone. The X-ray fluorescence measurements were performed at the Radiation Measurements and Spectroscopy Laboratory (RMSL) of department of nuclear engineering of Missouri University of Science and Technology and different kidney stones were acquired from the Mayo Clinic, Rochester, Minnesota. Presently, experimental studies in conjunction with analytical techniques were used to determine the exact composition of the kidney stone. A new type of experimental set-up was developed and utilized for XRF analysis of the kidney stone. The correlation of applied radiation source intensity, emission of X-ray spectrum from involving elements and absorption coefficient characteristics were analyzed. To verify the experimental results with analytical calculation, several sets of kidney stones were analyzed using XRF technique. The elements which were identified from this techniques are Silver (Ag), Arsenic (As), Bromine (Br), Chromium (Cr), Copper (Cu), Gallium (Ga), Germanium (Ge), Molybdenum (Mo), Niobium (Nb), Rubidium (Rb), Selenium (Se), Strontium (Sr), Yttrium (Y), Zirconium (Zr). This paper presents a new approach for exact detection of accurate material composition of kidney stone materials using XRF instrumental activation analysis technique.

  14. Capillary electrophoresis micro X-ray fluorescence: a tool for benchtop elemental analysis.

    Science.gov (United States)

    Miller, Thomasin C; Joseph, Martha R; Havrilla, George J; Lewis, Cris; Majidi, Vahid

    2003-05-01

    A new tool was developed for separation and elemental detection by interfacing a simple capillary electrophoresis (CE) apparatus, constructed using a thin-walled fused-silica capillary, with a benchtop energy-dispersive micro X-ray fluorescence (MXRF) system. X-ray excitation and detection of the separated analytes was done using an EDAX Eagle II micro X-ray fluorescence system equipped with a polycapillary Rh target excitation source and a SiLi detector. It was demonstrated that this prototype system could be used for the separation and detection of species containing two different metals from one another, specifically Cu and Co. Free Co could also be separated from Co bound to cyanocobalamin (vitamin B-12). Two organic compounds were also separated from one another, a large biological protein, ferritin, from a small biological organic, cyanocobalamin. Preliminary average detection limits obtained on this system were on the order of 10(-)(4) M and compared favorably to those reported for the similar technique of CE-synchrotron XRF. CEMXRF allows for nondestructive, simultaneous, on-line, benchtop elemental analysis for chemical speciation applications.

  15. A new method for x-ray fluorescence analysis of contaminated material. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Grodzins, Lee; Niland, John

    2002-05-23

    Niton has successfully completed the objectives of the Phase II program to build a hand-held, x-ray fluorescent analyzer optimized for DOE decontamination and decommissioning activities in the field. A two-pound x-ray fluorescence analyzer was developed that contains 3 radioactive sources, emitting 3 widely spaced monochromatic x-rays, to give the lowest detection limits for the full range of toxic elements, from chromium to plutonium. A rapid, fundamental- parameters algorithm was developed that yields quantitative results in less than 1 second. High-resolution silicon drift detectors and silicon PIN diodes give excellent efficiency and speed. These results from Phase II have been introduced into the XL 300, 700 and 800 commercial products series. More than 800 of these instruments, yielding revenues of more than $20 million dollars, have been sold since the first 3-source instrument was introduced in 1998. A direct consequence of the Phase II funding has been the growth of Niton from 20 people to its present size of 60.

  16. A novel portable energy dispersive X-ray fluorescence spectrometer with triaxial geometry

    Science.gov (United States)

    Pessanha, S.; Alves, M.; Sampaio, J. M.; Santos, J. P.; Carvalho, M. L.; Guerra, M.

    2017-01-01

    The X-ray fluorescence technique is a powerful analytical tool with a broad range of applications such as quality control, environmental contamination by heavy metals, cultural heritage, among others. For the first time, a portable energy dispersive X-ray fluorescence spectrometer was assembled, with orthogonal triaxial geometry between the X-ray tube, the secondary target, the sample and the detector. This geometry reduces the background of the measured spectra by reducing significantly the Bremsstrahlung produced in the tube through polarization in the secondary target and in the sample. Consequently, a practically monochromatic excitation energy is obtained. In this way, a better peak-background ratio is obtained compared to similar devices, improving the detection limits and leading to superior sensitivity. The performance of this setup is compared with the one of a benchtop setup with triaxial geometry and a portable setup with planar geometry. Two case studies are presented concerning the analysis of a 18th century paper document, and the bone remains of an individual buried in the early 19th century.

  17. X-ray fluorescence microtomography on a SiC nuclear fuel shell

    Energy Technology Data Exchange (ETDEWEB)

    Naghedolfeizi, M.; Chung, J.S.; Ice, G.E. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Yun, W.B.; Cai, Z.; Lai, B. [Argonne National Lab., IL (United States). Advanced Photon Source

    1998-12-31

    TRISO fuel particles contain a small kernel of nuclear fuel encapsulated by alternating layers of C and a barrier layer of SiC. The TRISO fuel particle is used in an advanced nuclear fuel where the SiC shell provides the primary barrier for radioactive elements in the kernel. The performance of this barrier is key to containment. The authors have used x-ray fluorescence microtomography to measure the trace element distribution in a SiC shell. Prior to the measurements the nuclear fuel and C layers were leached from the particle. The shell was then encapsulated by kapton tape to simplify handling. The shell was mounted on a glass fiber and measurements were made with an {approximately} 1 x 3 {micro}m{sup 2} x-ray probe on beamline 2-ID at the APS. The distribution of trace elements in the SiC shell was reconstructed after correcting the data for artifacts arising from absorption and scattering off the kapton tape. The observed trace elements are distributed in small < 1 {micro}m regions through the SiC shell. The trace elements can be attributed to radiation enhanced diffusion of elements in the kernel or to trace elements introduced during fabrication. X-ray fluorescence microtomography is an ideal tool for this work because it is a penetrating nondestructive probe sensitive to trace elements in a low Z matrix and because it provides a picture of the elemental distribution in the shell.

  18. Development of a single-cell X-ray fluorescence flow cytometer.

    Science.gov (United States)

    Crawford, Andrew M; Kurecka, Patrick; Yim, Tsz Kwan; Kozemchak, Claire; Deb, Aniruddha; Dostál, Lubomír; Sun, Cheng Jun; Brewe, Dale L; Barrea, Raul; Penner-Hahn, James E

    2016-07-01

    An X-ray fluorescence flow cytometer that can determine the total metal content of single cells has been developed. Capillary action or pressure was used to load cells into hydrophilic or hydrophobic capillaries, respectively. Once loaded, the cells were transported at a fixed vertical velocity past a focused X-ray beam. X-ray fluorescence was then used to determine the mass of metal in each cell. By making single-cell measurements, the population heterogeneity for metals in the µM to mM concentration range on fL sample volumes can be directly measured, a measurement that is difficult using most analytical methods. This approach has been used to determine the metal composition of 936 individual bovine red blood cells (bRBC), 31 individual 3T3 mouse fibroblasts (NIH3T3) and 18 Saccharomyces cerevisiae (yeast) cells with an average measurement frequency of ∼4 cells min(-1). These data show evidence for surprisingly broad metal distributions. Details of the device design, data analysis and opportunities for further sensitivity improvement are described.

  19. Scanning protein analysis of electrofocusing gels using X-ray fluorescence.

    Science.gov (United States)

    Matsuyama, Satoshi; Matsunaga, Akihiro; Sakamoto, Shinichi; Iida, Yutaka; Suzuki, Yoshinari; Ishizaka, Yukihito; Yamauchi, Kazuto; Ishikawa, Tetsuya; Shimura, Mari

    2013-05-01

    Recently, "metallomics," in addition to genomics and proteomics, has become a focus as a novel approach to identify sensitive fluctuations in homeostasis that accompany metabolic processes, such as stress responses, differentiation, and proliferation. Cellular elements and associated protein behavior provide important clues for understanding cellular and disease mechanism(s). It is important to develop a system for measuring the native status of the protein. In this study, we developed an original freeze-dried electrofocusing native gel over polyimide film (native-gel film) for scanning protein analysis using synchrotron radiation excited X-ray fluorescence (SPAX). To our knowledge, this is the first report detailing the successful mapping of metal-associated proteins of electrofocusing gels using X-ray fluorescence. SPAX can provide detection sensitivity equivalent to that of LA-ICP-MS. In addition to this increased sensitivity, SPAX has the potential to be combined with other X-ray spectroscopies. Our system is useful for further applications in proteomics investigating cellular element-associated protein behaviors and disease mechanisms.

  20. Dose distribution calculation for in-vivo X-ray fluorescence scanning

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa, R. G. [Universidad de la Frontera, Departamento de Ciencias Fisicas, Av. Francisco Salazar 1145, Temuco 4811230, Araucania (Chile); Lozano, E. [Instituto Nacional del Cancer, Unidad de Fisica Medica, Av. Profesor Zanartu 1010, Santiago (Chile); Valente, M., E-mail: figueror@ufro.cl [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Av. Ravadavia 1917, C1033AAJ, Buenos Aires (Argentina)

    2013-08-01

    In-vivo X-ray fluorescence constitutes a useful and accurate technique, worldwide established for constituent elementary distribution assessment. Actually, concentration distributions of arbitrary user-selected elements can be achieved along sample surface with the aim of identifying and simultaneously quantifying every constituent element. The method is based on the use of a collimated X-ray beam reaching the sample. However, one common drawback for considering the application of this technique for routine clinical examinations was the lack of information about associated dose delivery. This work presents a complete study of the dose distribution resulting from an in-vivo X-ray fluorescence scanning for quantifying biohazard materials on human hands. Absorbed dose has been estimated by means of dosimetric models specifically developed to this aim. In addition, complete dose distributions have been obtained by means of full radiation transport calculations in based on stochastic Monte Carlo techniques. A dedicated subroutine has been developed using the Penelope 2008 main code also integrated with dedicated programs -Mat Lab supported- for 3 dimensional dose distribution visualization. The obtained results show very good agreement between approximate analytical models and full descriptions by means of Monte Carlo simulations. (Author)

  1. X-ray Absorption Spectroscopy and Coherent X-ray Diffraction Imaging for Time-Resolved Investigation of the Biological Complexes: Computer Modelling towards the XFEL Experiment

    Science.gov (United States)

    Bugaev, A. L.; Guda, A. A.; Yefanov, O. M.; Lorenz, U.; Soldatov, A. V.; Vartanyants, I. A.

    2016-05-01

    The development of the next generation synchrotron radiation sources - free electron lasers - is approaching to become an effective tool for the time-resolved experiments aimed to solve actual problems in various fields such as chemistry’ biology’ medicine’ etc. In order to demonstrate’ how these experiments may be performed for the real systems to obtain information at the atomic and macromolecular levels’ we have performed a molecular dynamics computer simulation combined with quantum chemistry calculations for the human phosphoglycerate kinase enzyme with Mg containing substrate. The simulated structures were used to calculate coherent X-ray diffraction patterns’ reflecting the conformational state of the enzyme, and Mg K-edge X-ray absorption spectra, which depend on the local structure of the substrate. These two techniques give complementary information making such an approach highly effective for time-resolved investigation of various biological complexes, such as metalloproteins or enzymes with metal-containing substrate, to obtain information about both metal-containing active site or substrate and the atomic structure of each conformation.

  2. Sum rule distortions in fluorescence-yield x-ray magnetic circular dichroism

    Science.gov (United States)

    Liu, Boyang; Piamonteze, Cinthia; Delgado-Jaime, Mario Ulises; Wang, Ru-Pan; Heidler, Jakoba; Dreiser, Jan; Chopdekar, Rajesh; Nolting, Frithjof; de Groot, Frank M. F.

    2017-08-01

    The quantitative analysis of 3 d transition metal L2 ,3 edge x-ray magnetic circular dichroism (XMCD) spectra and the related sum rules are compared for measurements with electron yield and fluorescence yield detection. Multiplet calculations on divalent ions show that fluorescence yield detected sum rule derived expectation values of Lz and Sz show noticeable deviations and detection angle dependence. We show that small deviations of the polarization dependent fluorescent decay values lead to significant deviations in the Lz and Sz sum rule values. Fe and Co experimental XMCD spectra of a supported 10 nm CoFe2O4 thin film are measured simultaneously by both electron and fluorescence yield. The deviations shown in the experimental data are well explained by the calculations and are shown to mainly depend on the polarization dependent total decay. We conclude that fluorescence yield detected x-ray magnetic circular dichroism is unsuitable for quantitative analysis of the Lz and Sz sum rule values.

  3. Uranium determination at ppb levels by X-ray fluorescence after its preconcentration on polyurethane foam

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, M.S.; Domingues, M.D.L.F.; Mantovano, J.L.; Filho, E.Q.S. [Instituto de Engenharia Nuclear, CNEN-RJ, CP 68550, 21945-590 (Brazil)

    1998-12-28

    A sensitive method based on the preconcentration of uranium on powdered polyurethane foam (PUF) has been developed to determinate this element in water samples by X-ray florescence. Uranium at ppb levels was sorbed as the salicylate complex on powdered PUF at pH 4.0. The resulting PUF was filtered through a filter paper and used for X-ray fluorescence measurements. For 50 {mu}g/l of uranium the coefficient of variation for five measurements is 5% and the detection limit is 5.5 {mu}g/l. The interference level of various ions and ligands was studied and optimum conditions were developed to determine uranium in reference materials, waste water, mine drainage, and sea water. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Trace element determination in amniotic fluid by total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Greaves, E.D.; Sajo-Bohus, L.; Castelli, C.; Borgerg, C. [Universidad Simon Bolivar, Caracas (Venezuela); Meitin, J.; Liendo, J.

    1995-03-01

    A new method is reported for the determination of Fe, Cu, Zn, and Br in amniotic fluid (AF) by Total Reflection X-Ray Fluorescence. The irradiation of AF samples with monochromatic X-Rays reduces the scattering background from the organic matrix and avoids the need for sample digestion. Sample manipulation is reduced to centrifuging and adding cobalt as internal standard. Lower detection limits obtained are 109, 53, 44 and 37 ppb for Fe, Cu, Zn and Br respectively. Measurement precision depends on element concentrations and can be as low as 1.5% SD. Results of the analysis of 34 AF samples from Venezuelan pregnant patients agree with previously reported ranges of Fe, Cu and Zn. Other elements observed but not quantified are Cl, K, Ca in all spectra and Pb and Sr in some of them. (author).

  5. Metals determination in wood treated by synchrotron radiation X-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Silva, Richard Maximiliano da Cunha [Centro de Energia Nuclear na Agricultura, Piracicaba, SP (Brazil)]. E-mail: maxcunha@cena.usp.br; Medeiros, Jean Gabriel da Silva; Tomazello Filho, Mario [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz]. E-mail: jeangm@esalq.usp.br; mtomazel@esalq.usp.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Barroso, Regina Cely [Universidade do Estado, Rio de Janeiro, RJ (Brazil)]. E-mail: cely@uerj.br

    2005-07-01

    The paper describes the use of X-Ray fluorescence analysis for distribution and quantification of metals in the hardwood (Eucalyptus sp) and softwood (Pinus sp) treated with CCA (copper-chromium-arsenic). The sapwood/heartwood for hardwood sample and the growth-rings for softwood sample were analyzed. The samples were scanned in 320 mm steps in the vertical direction. For excitation of the elements a white beam synchrotron radiation of {approx} 320 x 180 mm was employed and for the X-ray detection a Si(Li) semiconductor detector. The elements K, Ca, Cr, Mn, Cu, Zn and As were determined. Fundamental parameters were used to quantify the elements concentrations. (author)

  6. Elemental distribution images in prostate samples by X-ray fluorescence microtomography

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, G.R. [Non-destructive Testing, Corrosion and Welding Laboratory, PEMM/COPPE/UFRJ, Rio de Janeiro (Brazil); Rocha, H.S. [Nuclear Instrumentation Laboratory, PEN/COPPE/UFRJ, P.O. Box 68509, 21.941-972, Rio de Janeiro (Brazil); Anjos, M.J. [Physics Institute-Stated University of Rio de Janeiro, Rio de Janeiro (Brazil); Lima, I. [Nuclear Instrumentation Laboratory, PEN/COPPE/UFRJ, P.O. Box 68509, 21.941-972, Rio de Janeiro (Brazil); Lopes, R.T., E-mail: ricardo@lin.ufrj.br [Nuclear Instrumentation Laboratory, PEN/COPPE/UFRJ, P.O. Box 68509, 21.941-972, Rio de Janeiro (Brazil)

    2012-07-15

    An X-ray transmission microtomography (CT) system combined with an X-ray fluorescence microtomography (XRF{mu}CT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), in order to determine the elemental distribution in prostate samples aiming at establishing a correlation between the concentration of some elements and the characteristics and pathology of the tissues. The CT images were reconstructed using a filtered-back projection algorithm and the XRF{mu}CT images were reconstructed using a filtered-back projection algorithm with absorption corrections. - Highlights: Black-Right-Pointing-Pointer In this study we evaluated prostate tissues by microtomography imaging techniques. Black-Right-Pointing-Pointer The elemental distribution of iron, copper and zinc was obtained in each sample. Black-Right-Pointing-Pointer The great advantage of this technique is the visualization in three-dimension. Black-Right-Pointing-Pointer The elemental distribution visualization was obtained without damaging the material.

  7. Reverse engineering the ancient ceramic technology based on X-ray fluorescence spectromicroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sciau, Philippe; Leon, Yoanna; Goudeau, Philippe; Fakra, Sirine C.; Webb, Sam; Mehta, Apurva

    2011-07-06

    We present results of X-ray fluorescence (XRF) microprobe analyses of ancient ceramic cross-sections aiming at deciphering the different firing protocols used for their production. Micro-focused XRF elemental mapping, Fe chemical mapping and Fe K-edge X-ray absorption near edge structure spectroscopy were performed on pre-sigillata ceramics from southern Gaul, and terra Sigillata vessels from Italy and southern Gaul. Pieces from the different workshops and regions showed significant difference in the starting clay material, clay conditioning and kiln firing condition. By contrast, sherds from the same workshop exhibited more subtle differences and possible misfirings. Understanding the precise firing conditions and protocols would allow recreation of kilns for various productions. Furthermore, evolution and modification of kiln design would shed some light on how ancient potters devised solutions to diverse technological problems they encountered.

  8. Use of x-ray fluorescence and diffraction techniques in studying ancient ceramics of Sri Lanka

    Science.gov (United States)

    Karunaratne, B. S. B.

    2012-07-01

    Ceramics were produced for centuries in Sri Lanka for various purposes. Ancient ceramic articles such as pottery, bricks, tiles, sewer pipes, etc, were made from naturally occurring raw materials. Use of X-ray fluorescence (XRF), X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) in characterizing of two ancient ceramic samples from two different archaeological sites in Sri Lanka is presented. The information obtained in this manner is used to figure out the ancient ceramic technology, particularly to learn about the raw materials used, the source of raw materials, processing parameters such as firing temperature or binders used in ceramic production. This information then can be used to explore the archaeometric background such as the nature and extent of cultural and technological interaction between different periods of history in Sri Lanka.

  9. X-Ray Diffraction and Fluorescence Measurements for In-situ Planetary Instruments

    Science.gov (United States)

    Hansford, G.; Hill, K. S.; Vernon, D.; Ambrosi, R. M.; Bridges, J.; Hutchinson, I.

    2010-12-01

    The X-Ray Diffraction (XRD) instruments are core components of the forthcoming NASA Mars Science Laboratory (MSL) and ESA/NASA EXOMARS missions and will provide the first demonstrations of an XRF/XRD instrument’s capabilities in-situ on an extraterrestrial planetary surface. The University of Leicester team is part of the Italy-UK collaboration that is responsible for building the ExoMars X-Ray Diffraction instrument, Mars XRD. The ExoMars X-ray diffraction instrument incorporates an 55-Fe radioisotope source and three fixed-position CCDs to simultaneously acquire an X-Ray fluorescence spectrum and a diffraction pattern providing a measurement of both elemental and mineralogical composition [1]. The CCDs cover an angular range from 6 to 65-deg enabling the analysis of silicates, from clays, or other phyllosilicates characterised by varying d-spacings, to oxides, and carbonates or evaporites. The identification of hydrous minerals may help identify past Martian hydrothermal systems capable of preserving traces of life. Here we present some initial findings from XRF and XRD tests carried out at the University of Leicester using an 55-Fe source and X-ray sensitive CCD [1]. The XRD/XRD test system consists of a single CCD on a motorised arm, an 55-Fe X-ray source, source collimator and a sample table which approximately replicate the reflection geometry of the XRD instrument. It was used to test geological reference standard materials and Martian analogues. Incidence angle and CCD angles on both the diffraction and fluorescence results were evaluated. A key area of interest is the effect of sample roughness on the XRD/XRF results. We present results from testing pressed powder pellet samples of varying surface roughness, and a comparison with model results [2]. So far we have found that increased roughness causes a reduced intensity at lower take-off angles. Several methods for measuring surface roughness of the samples have been used including an Alicona Infinite

  10. Advanced combined application of micro-X-ray diffraction/micro-X-ray fluorescence with conventional techniques for the identification of pictorial materials from Baroque Andalusia paintings.

    Science.gov (United States)

    Herrera, L K; Montalbani, S; Chiavari, G; Cotte, M; Solé, V A; Bueno, J; Duran, A; Justo, A; Perez-Rodriguez, J L

    2009-11-15

    The process of investigating paintings includes the identification of materials to solve technical and historical art questions, to aid in the deduction of the original appearance, and in the establishment of the chemical and physical conditions for adequate restoration and conservation. In particular, we have focused on the identification of several samples taken from six famous canvases painted by Pedro Atanasio Bocanegra, who created a very special collection depicting the life of San Ignacio, which is located in the church of San Justo y Pastor of Granada, Spain. The characterization of the inorganic and organic compounds of the textiles, preparation layers, and pictorial layers have been carried out using an XRD diffractometer, SEM observations, EDX spectrometry, FT-IR spectrometry (both in reflection and transmission mode), pyrolysis/gas chromatography/mass spectrometry and synchrotron-based micro-X-ray techniques. In this work, the advantages over conventional X-ray diffraction of using combined synchrotron-based micro-X-ray diffraction and micro-X-ray fluorescence in the identification of multi-layer paintings is demonstrated.

  11. Development of a reconstruction software of elemental maps by micro X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Andre Pereira de; Braz, Delson; Mota, Carla Lemos, E-mail: apalmeid@gmail.co, E-mail: delson@lin.ufrj.b, E-mail: clemos@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Energia Nuclear; Oliveira, Luis Fernando de; Barroso, Regina Cely; Pinto, Nivia Graciele Villela, E-mail: cely@uerj.b, E-mail: lfolive@uerj.b, E-mail: nitatag@gmail.co [Universidade do Estado do Rio de Janeiro (IF/UERJ), RJ (Brazil). Inst. de Fisica; Cardoso, Simone Coutinho [Universidade Federal do Rio de Janeiro (IF/UFRJ), RJ (Brazil). Inst. de Fisica; Moreira, Silvana [Universidade Estadual de Campinas (FEC/UNICAMP), SP (Brazil) Faculdade de Engenharia Civil, Arquitetura e Urbanismo

    2009-07-01

    The technique of X-ray fluorescence (XRF) using SR microbeams is a powerful analysis tool for studying elemental composition in several samples. One application of this technique is the analysis done through the mapping of chemical elements forming a matrix of data. The aim of this work is the presentation of the program MapXRF, an in-house software designed to optimize the processing and mapping of fluorescence intensities data. This program uses spectra generated by QXAS as input data and separates the intensities of each chemical element found in the fluorescence spectra in files themselves. From these files, the program generates the intensity maps that can be visualized in any program of treatment of images. The proposed software was tested using fluorescence data obtained in the XRF beamline at National Synchrotron Light Laboratory (LNLS), Brazil. Automatic 2D scans were performed and element distribution maps were obtained in form of a matrix of data. (author)

  12. Development of a software for reconstruction of X-ray fluorescence intensity maps

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Andre Pereira de; Braz, Delson; Mota, Carla Lemos, E-mail: apalmeid@gmail.co, E-mail: delson@lin.ufrj.b, E-mail: clemos@con.ufrj.b [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Oliveira, Luis Fernando de; Barroso, Regina Cely; Pinto, Nivia Graciele Villela, E-mail: cely@uerj.b, E-mail: lfolive@uerj.b, E-mail: nitatag@gmail.co [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica; Cardoso, Simone Coutinho, E-mail: simone@if.ufrj.b [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Fisica; Moreira, Silvana, E-mail: silvana@fec.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo

    2009-07-01

    The technique of X-ray fluorescence (XRF) using SR microbeams is a powerful analysis tool for studying elemental composition in several samples. One application of this technique is the analysis done through the mapping of chemical elements forming a matrix of data. The aim of this work is the presentation of the program MapXRF, an in-house software designed to optimize the processing and mapping of fluorescence intensities data. This program uses spectra generated by QXAS as input data and separates the intensities of each chemical element found in the fluorescence spectra in files themselves. From these files, the program generates the intensity maps that can be visualized in any program of treatment of images. The proposed software was tested using fluorescence data obtained in the XRF beamline of XRF at Synchrotron Light National Laboratory (LNLS), Brazil. Automatic 2D scans were performed and element distribution maps were obtained in the form of a matrix of data. (author)

  13. X-ray fluorescent lines from the Compton-thick AGN in M5

    CERN Document Server

    Xu, Weiwei; Gou, Lijun; Liu, Jiren

    2015-01-01

    The cold disk/torus gas surrounding AGN emits fluorescent lines when irradiated by hard X-ray photons. The fluorescent lines of elements other than Fe and Ni are rarely detected due to their relative faintness. We report the detection of K$\\alpha$ lines of neutral Si, S, Ar, Ca, Cr, and Mn, along with the prominent Fe K$\\alpha$, Fe K$\\beta$, and Ni K$\\alpha$ lines, from the deep Chandra observation of the low-luminosity Compton-thick AGN in M51. The Si K$\\alpha$ line at 1.74 keV is detected at $\\sim3\\sigma$, the other fluorescent lines have a significance between 2 and 2.5 $\\sigma$, while the Cr line has a significance of $\\sim1.5\\sigma$. These faint fluorescent lines are made observable due to the heavy obscuration of the intrinsic spectrum of M51, which is revealed by Nustar observation above 10 keV. The hard X-ray continuum of M51 from Chandra and Nustar can be fitted with a power-law spectrum with an index of 1.8, reprocessed by a torus with an equatorial column density of $N_{\\rm H}\\sim7\\times10^{24}$ cm...

  14. Feasibility study of Compton cameras for x-ray fluorescence computed tomography with humans.

    Science.gov (United States)

    Vernekohl, Don; Ahmad, Moiz; Chinn, Garry; Xing, Lei

    2016-12-21

    X-ray fluorescence imaging is a promising imaging technique able to depict the spatial distributions of low amounts of molecular agents in vivo. Currently, the translation of the technique to preclinical and clinical applications is hindered by long scanning times as objects are scanned with flux-limited narrow pencil beams. The study presents a novel imaging approach combining x-ray fluorescence imaging with Compton imaging. Compton cameras leverage the imaging performance of XFCT and abolish the need for pencil beam excitation. The study examines the potential of this new imaging approach on the base of Monte-Carlo simulations. In the work, it is first presented that the particular option of slice/fan-beam x-ray excitation has advantages in image reconstruction in regard of processing time and image quality compared to traditional volumetric Compton imaging. In a second experiment, the feasibility of the approach for clinical applications with tracer agents made from gold nano-particles is examined in a simulated lung scan scenario. The high energy of characteristic x-ray photons from gold is advantageous for deep tissue penetration and has lower angular blurring in the Compton camera. It is found that Doppler broadening in the first detector stage of the Compton camera adds the largest contribution on the angular blurring; physically limiting the spatial resolution. Following the analysis of the results from the spatial resolution test, resolutions in the order of one centimeter are achievable with the approach in the center of the lung. The concept of Compton imaging allows one to distinguish to some extent between scattered photons and x-ray fluorescent photons based on their difference in emission position. The results predict that molecular sensitivities down to 240 pM l(-1) for 5 mm diameter lesions at 15 mGy for 50 nm diameter gold nano-particles are achievable. A 45-fold speed up time for data acquisition compared to traditional pencil beam XFCT could

  15. Feasibility study of Compton cameras for x-ray fluorescence computed tomography with humans

    Science.gov (United States)

    Vernekohl, Don; Ahmad, Moiz; Chinn, Garry; Xing, Lei

    2016-12-01

    X-ray fluorescence imaging is a promising imaging technique able to depict the spatial distributions of low amounts of molecular agents in vivo. Currently, the translation of the technique to preclinical and clinical applications is hindered by long scanning times as objects are scanned with flux-limited narrow pencil beams. The study presents a novel imaging approach combining x-ray fluorescence imaging with Compton imaging. Compton cameras leverage the imaging performance of XFCT and abolish the need for pencil beam excitation. The study examines the potential of this new imaging approach on the base of Monte-Carlo simulations. In the work, it is first presented that the particular option of slice/fan-beam x-ray excitation has advantages in image reconstruction in regard of processing time and image quality compared to traditional volumetric Compton imaging. In a second experiment, the feasibility of the approach for clinical applications with tracer agents made from gold nano-particles is examined in a simulated lung scan scenario. The high energy of characteristic x-ray photons from gold is advantageous for deep tissue penetration and has lower angular blurring in the Compton camera. It is found that Doppler broadening in the first detector stage of the Compton camera adds the largest contribution on the angular blurring; physically limiting the spatial resolution. Following the analysis of the results from the spatial resolution test, resolutions in the order of one centimeter are achievable with the approach in the center of the lung. The concept of Compton imaging allows one to distinguish to some extent between scattered photons and x-ray fluorescent photons based on their difference in emission position. The results predict that molecular sensitivities down to 240 pM l-1 for 5 mm diameter lesions at 15 mGy for 50 nm diameter gold nano-particles are achievable. A 45-fold speed up time for data acquisition compared to traditional pencil beam XFCT could

  16. Application of synchrotron x-ray fluorescence microscopy to the study of multi-metal oxide ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Perry, D.L. [Lawrence Berkeley National Lab., CA (United States)]|[Univ. of California, Berkeley, CA (United States). G.T. Seaborg Inst. for Transactinium Science; McHugo, S.; Thompson, A.C. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1998-12-31

    Synchrotron x-ray fluorescence microscopy has been used to study multi-metal oxide ceramics that have been designed to sequester radioactive actinide elements for long-term storage and disposal. X-ray fluorescent lines for the various elements have been used for lateral elemental mapping of the materials, and the heterogeneity of the samples is discussed with respect to the elements in the crystallographic phases that have previously been documented by other means of structural and chemical analyses.

  17. Internal elemental imaging by scanning X-ray fluorescence microtomography at the hard X-ray microprobe beamline of the SSRF: Preliminary experimental results

    Science.gov (United States)

    Qiu, Jingke; Deng, Biao; Yang, Qun; Yan, Fen; Li, Aiguo; Yu, Xiaohan

    2011-11-01

    Synchrotron-based X-ray micro-fluorescence (μ-SXRF) is a non-destructive analytical technique and has been widely used to detect and quantify the elemental composition of samples in their natural state. To determine the internal elemental distributions within samples, X-ray fluorescence microtomography has been developed based on the hard X-ray microprobe at beamline BL15U1 of the Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China. This technique was applied to image the cross-sectional distributions of multiple elements within a single human hair, and its validity was evaluated by comparing the results with the elemental maps of a thin hair section obtained using the well-established μ-SXRF mapping method. Elemental images of S, Ca, Mn, Fe, Cu, and Zn within a virtual slice of the hair were reconstructed after the tomographic measurements. The tomographic images of heavy elements like Fe, Cu, and Zn were found to be in good agreement with the corresponding μ-SXRF maps. Light elements, such as S, however, represented different patterns due to non-negligible self-absorption in the sample, and sophisticated correction algorithms accounting for such effects are required for obtaining qualitatively and quantitatively more accurate images. Compared to μ-SXRF mapping, X-ray fluorescence microtomography reduces the sample preparation requirements and has been demonstrated in this work as being a more ideal and effective imaging modality to non-destructively mapping out the internal distribution of heavy elements within samples at the micrometer scale at the SSRF.

  18. Analysis of nuclear materials by energy dispersive x-ray fluorescence and spectral effects of alpha decay

    Energy Technology Data Exchange (ETDEWEB)

    Worley, Christopher G [Los Alamos National Laboratory

    2009-01-01

    Energy dispersive X-ray fluorescence (EDXRF) spectra collected from alpha emitters are complicated by artifacts inherent to the alpha decay process, particularly when using portable instruments. For example, {sup 239}Pu EDXRF spectra exhibit a prominent uranium L X-ray emission peak series due to sample alpha decay rather than source-induced X-ray fluorescence. A portable EDXRF instrument was used to collect spectra from plutonium, americium, and a Pu-contaminated steel sample. The plutonium sample was also analyzed by wavelength dispersive XRF to demonstrate spectral differences observed when using these very different instruments.

  19. Experimental station for laser-based picosecond time-resolved x-ray absorption near-edge spectroscopy

    Science.gov (United States)

    Dorchies, F.; Fedorov, N.; Lecherbourg, L.

    2015-07-01

    We present an experimental station designed for time-resolved X-ray Absorption Near-Edge Spectroscopy (XANES). It is based on ultrashort laser-plasma x-ray pulses generated from a table-top 100 mJ-class laser at 10 Hz repetition rate. A high transmission (10%-20%) x-ray beam line transport using polycapillary optics allows us to set the sample in an independent vacuum chamber, providing high flexibility over a wide spectral range from 0.5 up to 4 keV. Some XANES spectra are presented, demonstrating 1% noise level in only ˜1 mn and ˜100 cumulated laser shots. Time-resolved measurements are reported, indicating that the time resolution of the entire experimental station is 3.3 ± 0.6 ps rms.

  20. Experimental station for laser-based picosecond time-resolved x-ray absorption near-edge spectroscopy.

    Science.gov (United States)

    Dorchies, F; Fedorov, N; Lecherbourg, L

    2015-07-01

    We present an experimental station designed for time-resolved X-ray Absorption Near-Edge Spectroscopy (XANES). It is based on ultrashort laser-plasma x-ray pulses generated from a table-top 100 mJ-class laser at 10 Hz repetition rate. A high transmission (10%-20%) x-ray beam line transport using polycapillary optics allows us to set the sample in an independent vacuum chamber, providing high flexibility over a wide spectral range from 0.5 up to 4 keV. Some XANES spectra are presented, demonstrating 1% noise level in only ∼1 mn and ∼100 cumulated laser shots. Time-resolved measurements are reported, indicating that the time resolution of the entire experimental station is 3.3 ± 0.6 ps rms.

  1. Experimental station for laser-based picosecond time-resolved x-ray absorption near-edge spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dorchies, F., E-mail: dorchies@celia.u-bordeaux1.fr; Fedorov, N.; Lecherbourg, L. [Université Bordeaux, CNRS, CEA, CELIA (Centre Lasers Intenses et Applications), UMR 5107, Talence F-33405 (France)

    2015-07-15

    We present an experimental station designed for time-resolved X-ray Absorption Near-Edge Spectroscopy (XANES). It is based on ultrashort laser-plasma x-ray pulses generated from a table-top 100 mJ-class laser at 10 Hz repetition rate. A high transmission (10%–20%) x-ray beam line transport using polycapillary optics allows us to set the sample in an independent vacuum chamber, providing high flexibility over a wide spectral range from 0.5 up to 4 keV. Some XANES spectra are presented, demonstrating 1% noise level in only ∼1 mn and ∼100 cumulated laser shots. Time-resolved measurements are reported, indicating that the time resolution of the entire experimental station is 3.3 ± 0.6 ps rms.

  2. Time-resolved soft-x-ray studies of energy transport in layered and planar laser-driven targets

    Energy Technology Data Exchange (ETDEWEB)

    Stradling, G.L.

    1982-04-19

    New low-energy x-ray diagnostic techniques are used to explore energy-transport processes in laser heated plasmas. Streak cameras are used to provide 15-psec time-resolution measurements of subkeV x-ray emission. A very thin (50 ..mu..g/cm/sup 2/) carbon substrate provides a low-energy x-ray transparent window to the transmission photocathode of this soft x-ray streak camera. Active differential vacuum pumping of the instrument is required. The use of high-sensitivity, low secondary-electron energy-spread CsI photocathodes in x-ray streak cameras is also described. Significant increases in sensitivity with only a small and intermittant decrease in dynamic range were observed. These coherent, complementary advances in subkeV, time-resolved x-ray diagnostic capability are applied to energy-transport investigations of 1.06-..mu..m laser plasmas. Both solid disk targets of a variety of Z's as well as Be-on-Al layered-disk targets were irradiated with 700-psec laser pulses of selected intensity between 3 x 10/sup 14/ W/cm/sup 2/ and 1 x 10/sup 15/ W/cm/sup 2/.

  3. Uncertainty calculations for the measurement of in vivo bone lead by x-ray fluorescence.

    Science.gov (United States)

    O'Meara, J M; Fleming, D E B

    2009-04-21

    In order to quantify the bone lead concentration from an in vivo x-ray fluorescence measurement, typically two estimates of the lead concentration are determined by comparing the normalized x-ray peak amplitudes from the Kalpha(1) and Kbeta(1) features to those of the calibration phantoms. In each case, the normalization consists of taking the ratio of the x-ray peak amplitude to the amplitude of the coherently scattered photon peak in the spectrum. These two Pb concentration estimates are then used to determine the weighted mean lead concentration of that sample. In calculating the uncertainties of these measurements, it is important to include any covariance terms where appropriate. When determining the uncertainty of the lead concentrations from each x-ray peak, the standard approach does not include covariance between the x-ray peaks and the coherently scattered feature. These spectral features originate from two distinct physical processes, and therefore no covariance between these features can exist. Through experimental and simulated data, we confirm that there is no observed covariance between the detected Pb x-ray peaks and the coherently scattered photon signal, as expected. This is in direct contrast to recent work published by Brito (2006 Phys. Med. Biol. 51 6125-39). There is, however, covariance introduced in the calculation of the weighted mean lead concentration due to the common coherent normalization. This must be accounted for in calculating the uncertainty of the weighted mean lead concentration, as is currently the case. We propose here an alternative approach to calculating the weighted mean lead concentration in such a way as to eliminate the covariance introduced by the common coherent normalization. It should be emphasized that this alternative approach will only apply in situations in which the calibration line intercept is not included in the calculation of the Pb concentration from the spectral data: when the source of the intercept is

  4. Synchrotron radiation micro-X-ray fluorescence analysis: A tool to increase accuracy in microscopic analysis

    CERN Document Server

    Adams, F

    2003-01-01

    Microscopic X-ray fluorescence (XRF) analysis has potential for development as a certification method and as a calibration tool for other microanalytical techniques. The interaction of X-rays with matter is well understood and modelling studies show excellent agreement between experimental data and calculations using Monte Carlo simulation. The method can be used for a direct iterative calculation of concentrations using available high accuracy physical constants. Average accuracy is in the range of 3-5% for micron sized objects at concentration levels of less than 1 ppm with focused radiation from SR sources. The end-station ID18F of the ESRF is dedicated to accurate quantitative micro-XRF analysis including fast 2D scanning with collection of full X-ray spectra. Important aspects of the beamline are the precise monitoring of the intensity of the polarized, variable energy beam and the high reproducibility of the set-up measurement geometry, instrumental parameters and long-term stability.

  5. New Homogeneous Standards by Atomic Layer Deposition for Synchrotron X-ray Fluorescence and Absorption Spectroscopies.

    Energy Technology Data Exchange (ETDEWEB)

    Butterworth, A.L.; Becker, N.; Gainsforth, Z.; Lanzirotti, A.; Newville, M.; Proslier, T.; Stodolna, J.; Sutton, S.; Tyliszczak, T.; Westphal, A.J.; Zasadzinski, J. (UCB)

    2012-03-13

    Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotron techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution

  6. Demonstration of a time-resolved x-ray scattering instrument utilizing the full-repetition rate of x-ray pulses at the Pohang Light Source

    Science.gov (United States)

    Jo, Wonhyuk; Eom, Intae; Landahl, Eric C.; Lee, Sooheyong; Yu, Chung-Jong

    2016-03-01

    We report on the development of a new experimental instrument for time-resolved x-ray scattering (TRXS) at the Pohang Light Source (PLS-II). It operates with a photon energy ranging from 5 to 18 keV. It is equipped with an amplified Ti:sappahire femtosecond laser, optical diagnostics, and laser beam delivery for pump-probe experiments. A high-speed single-element detector and high trigger-rate oscilloscope are used for rapid data acquisition. While this instrument is capable of measuring sub-nanosecond dynamics using standard laser pump/x-ray probe techniques, it also takes advantage of the dense 500 MHz standard fill pattern in the PLS-II storage ring to efficiently record nano-to-micro-second dynamics simultaneously. We demonstrate this capability by measuring both the (fast) impulsive strain and (slower) thermal recovery dynamics of a crystalline InSb sample following intense ultrafast laser excitation. Exploiting the full repetition rate of the storage ring results in a significant improvement in data collection rates compared to conventional bunch-tagging methods.

  7. [Establishment and Improvement of Portable X-Ray Fluorescence Spectrometer Detection Model Based on Wavelet Transform].

    Science.gov (United States)

    Li, Fang; Wang, Ji-hua; Lu, An-xiang; Han, Ping

    2015-04-01

    The concentration of Cr, Cu, Zn, As and Pb in soil was tested by portable X-ray fluorescence spectrometer. Each sample was tested for 3 times, then after using wavelet threshold noise filtering method for denoising and smoothing the spectra, a standard curve for each heavy metal was established according to the standard values of heavy metals in soil and the corresponding counts which was the average of the 3 processed spectra. The signal to noise ratio (SNR), mean square error (MSE) and information entropy (H) were taken to assess the effects of denoising when using wavelet threshold noise filtering method for determining the best wavelet basis and wavelet decomposition level. Some samples with different concentrations and H3 B03 (blank) were chosen to retest this instrument to verify its stability. The results show that: the best denoising result was obtained with the coif3 wavelet basis at the decomposition level of 3 when using the wavelet transform method. The determination coefficient (R2) range of the instrument is 0.990-0.996, indicating that a high degree of linearity was found between the contents of heavy metals in soil and each X-ray fluorescence spectral characteristic peak intensity with the instrument measurement within the range (0-1,500 mg · kg(-1)). After retesting and calculating, the results indicate that all the detection limits of the instrument are below the soil standards at national level. The accuracy of the model has been effectively improved, and the instrument also shows good precision with the practical application of wavelet transform to the establishment and improvement of X-ray fluorescence spectrometer detection model. Thus the instrument can be applied in on-site rapid screening of heavy metal in contaminated soil.

  8. Total reflection X-ray fluorescence and archaeometry: Application in the Argentinean cultural heritage

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, Cristina [Comision Nacional de Energia Atomica, Av. Gral Paz 1499 (B1650KNA) San Martin, Buenos Aires (Argentina); Laboratorio de Quimica de Sistemas Heterogeneos, Facultad de Ingenieria, Universidad de Buenos Aires, P. Colon 850 (C1063ACU), Buenos Aires (Argentina)], E-mail: Cristina.Vazquez@cnea.gov.ar; Albornoz, Ana [Agencia Rio Negro Cultura, Museo de la Patagonia F.P.Moreno, Centro Civico s/n Bariloche, Rio Negro (Argentina); Hajduk, Adam [CONICET, Museo de la Patagonia F.P.Moreno, Centro Civico s/n Bariloche, Rio Negro (Argentina); Elkin, Dolores [CONICET Instituto Nacional de Antropologia y Pensamiento Latinoamericano, 3 de febrero 1378 (C1426AEL) Buenos Aires (Argentina); Custo, Graciela; Obrustky, Alba [Comision Nacional de Energia Atomica, Av. Gral Paz 1499 (B1650KNA) San Martin, Buenos Aires (Argentina)

    2008-12-15

    Archaeometry is an interdisciplinary research area involved in the development and use of scientific methods in order to answer questions concerned with the human history. In this way the knowledge of archaeological objects through advanced chemical and physical analyses permits a better preservation and conservation of the cultural heritage and also reveals materials and technologies used in the past. In this sense, analytical techniques play an important role in order to provide chemical information about cultural objects. Considering the non destructive characteristic of this study, analytical techniques must be adequate in order to prevent any alteration or damage and in addition to allow the conservation of their integrity. Taking into account the irreplaceable character of the archaeological and artistic materials considered in this study, analytical techniques must be adequate in order to prevent any alteration or damage and in addition to allow the conservation of their integrity. Total Reflection X-ray Fluorescence Spectrometry as a geometric variant of conventional X-ray fluorescence is a proved microanalytical technique considering the small amount of sample required for the analysis. A few micrograms are enough in order to reveal valuable information about elemental composition and in this context it is highly recommended for artwork studies. In this paper a case study is presented in which Total Reflection X-Ray Fluorescence Spectrometry has been successfully employed in the archaeometry field. Examples from Argentinean cultural heritage sites related with the determination of pigments in paintings on canvas and in rock sites as well as in underwater archaeology research are shown.

  9. High temperature monitoring of silicon carbide ceramics by confocal energy dispersive X-ray fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fangzuo; Liu, Zhiguo; Sun, Tianxi, E-mail: stx@bnu.edu.cn

    2016-04-15

    Highlights: • X-ray scattering was used for monitoring oxidation situation of SiC ceramics. • A calibration curve was obtained. • The confocal X-ray scattering technology was based on polycapillary X-ray optics. • The variations of contents of components of SiC ceramics were obtained. - Abstract: In the present work, we presented an alternative method for monitoring of the oxidation situation of silicon carbide (SiC) ceramics at various high temperatures in air by measuring the Compton-to-Rayleigh intensity ratios (I{sub Co}/I{sub Ra}) and effective atomic numbers (Z{sub eff}) of SiC ceramics with the confocal energy dispersive X-ray fluorescence (EDXRF) spectrometer. A calibration curve of the relationship between I{sub Co}/I{sub Ra} and Z{sub eff} was established by using a set of 8 SiC calibration samples. The sensitivity of this approach is so high that it can be easily distinguished samples of Z{sub eff} differing from each other by only 0.01. The linear relationship between the variation of Z{sub eff} and the variations of contents of C, Si and O of SiC ceramics were found, and the corresponding calculation model of the relationship between the ΔZ and the ΔC{sub C}, ΔC{sub Si}, and ΔC{sub O} were established. The variation of contents of components of the tested SiC ceramics after oxidation at high temperature was quantitatively calculated based on the model. It was shown that the results of contents of carbon, silicon and oxygen obtained by this method were in good agreement with the results obtained by XPS, giving values of relative deviation less than 1%. It was concluded that the practicality of this proposed method for monitoring of the oxidation situation of SiC ceramics at high temperatures was acceptable.

  10. Characterization of the Carancas-Puno meteorite by energy dispersive X-ray fluorescence, X-ray diffractometry and transmission Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ceron Loayza, Maria L., E-mail: malucelo@hotmail.com; Bravo Cabrejos, Jorge A. [Universidad Nacional Mayor de San Marcos, Laboratorio de Analisis de Suelos, Facultad de Ciencias Fisicas (Peru)

    2011-11-15

    We report the results of the study of a meteorite that impacted an inhabited zone on 15 September 2007 in the neighborhood of the town of Carancas, Puno Region, about 1,300 km south of Lima. The analysis carried out by energy dispersive X-ray fluorescence, X-ray diffractometry and transmission Moessbauer spectroscopy (at room temperature and at 4.2 K), reveal the presence in the meteorite sample of magnetic sites assigned to taenite (Fe,Ni) and troilite (Fe,S) phases, and of two paramagnetic doublets assigned to Fe{sup 2 + }, one associated with olivine and the other to pyroxene. In accord with these results, this meteorite is classified as a type IV chondrite meteorite.

  11. Characterization of Japanese color sticks by energy dispersive X-ray fluorescence, X-ray diffraction and Fourier transform infrared analysis

    Energy Technology Data Exchange (ETDEWEB)

    Manso, M. [Centro de Fisica Atomica, Universidade de Lisboa, Faculdade de Ciencias, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal); Valadas, S. [Chemistry Department, Evora Chemistry Centre and HERCULES Centre, University of Evora, Rua Romao Ramalho, 59 Evora (Portugal); Pessanha, S.; Guilherme, A. [Centro de Fisica Atomica, Universidade de Lisboa, Faculdade de Ciencias, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal); Queralt, I. [Laboratory of X-ray Analytical Applications, Institute of Earth Sciences ' Jaume Almera' , CSIC, Sole Sabaris s/n. 08028 Barcelona (Spain); Candeias, A.E. [Chemistry Department, Evora Chemistry Centre and HERCULES Centre, University of Evora, Rua Romao Ramalho, 59 Evora (Portugal); Carvalho, M.L., E-mail: luisa@cii.fc.ul.p [Centro de Fisica Atomica, Universidade de Lisboa, Faculdade de Ciencias, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal)

    2010-04-15

    This work comprises the use of energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) techniques for the study of the composition of twentieth century traditional Japanese color sticks. By using the combination of analytical techniques it was possible to obtain information on inorganic and organic pigments, binders and fillers present in the sticks. The colorant materials identified in the sticks were zinc and titanium white, chrome yellow, yellow and red ochre, vermillion, alizarin, indigo, Prussian and synthetic ultramarine blue. The results also showed that calcite and barite were used as inorganic mineral fillers while Arabic gum was the medium used. EDXRF offered great potential for such investigations since it allowed the identification of the elements present in the sample preserving its integrity. However, this information alone was not enough to clearly identify some of the materials in study and therefore it was necessary to use XRD and FTIR techniques.

  12. Cloning, expression, purification and crystallization as well as X-ray fluorescence and preliminary X-ray diffraction analyses of human ADP-ribosylhydrolase 1.

    Science.gov (United States)

    Kernstock, Stefan; Koch-Nolte, Friedrich; Mueller-Dieckmann, Jochen; Weiss, Manfred S; Mueller-Dieckmann, Christoph

    2009-05-01

    Human ADP-ribosylhydrolase 1 (hARH1, ADPRH) cleaves the glycosidic bond of ADP-ribose attached to an Arg residue of a protein. hARH1 has been cloned, expressed heterologously in Escherichia coli, purified and crystallized in complex with K(+) and ADP. The orthorhombic crystals contained one monomer per asymmetric unit, exhibited a solvent content of 43% and diffracted X-rays to a resolution of 1.9 A. A prerequisite for obtaining well diffracting crystals was the performance of X-ray fluorescence analysis on poorly diffracting apo hARH1 crystals, which revealed the presence of trace amounts of K(+) in the crystal. Adding K-ADP to the crystallization cocktail then resulted in a crystal of different morphology and with dramatically improved diffraction properties.

  13. A new detector system for low energy X-ray fluorescence coupled with soft X-ray microscopy: First tests and characterization

    Science.gov (United States)

    Gianoncelli, Alessandra; Bufon, Jernej; Ahangarianabhari, Mahdi; Altissimo, Matteo; Bellutti, Pierluigi; Bertuccio, Giuseppe; Borghes, Roberto; Carrato, Sergio; Cautero, Giuseppe; Fabiani, Sergio; Giacomini, Gabriele; Giuressi, Dario; Kourousias, George; Menk, Ralf Hendrik; Picciotto, Antonino; Piemonte, Claudio; Rachevski, Alexandre; Rashevskaya, Irina; Stolfa, Andrea; Vacchi, Andrea; Zampa, Gianluigi; Zampa, Nicola; Zorzi, Nicola

    2016-04-01

    The last decades have witnessed substantial efforts in the development of several detector technologies for X-ray fluorescence (XRF) applications. In spite of the increasing trend towards performing, cost-effective and reliable XRF systems, detectors for soft X-ray spectroscopy still remain a challenge, requiring further study, engineering and customization in order to yield effective and efficient systems. In this paper we report on the development, first characterization and tests of a novel multielement detector system based on low leakage current silicon drift detectors (SDD) coupled to ultra low noise custom CMOS preamplifiers for synchrotron-based low energy XRF. This new system exhibits the potential for improving the count rate by at least an order of magnitude resulting in ten-fold shorter dwell time at an energy resolution similar to that of single element silicon drift detectors.

  14. A new detector system for low energy X-ray fluorescence coupled with soft X-ray microscopy: First tests and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Gianoncelli, Alessandra, E-mail: alessandra.gianoncelli@elettra.eu [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Bufon, Jernej [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); University of Trieste, Piazzale Europa 1, Trieste 34127 (Italy); Ahangarianabhari, Mahdi [Politecnico di Milano, Via Anzani 42, Como 22100 (Italy); INFN Milano, Via Celoria 16, Milano 20133 (Italy); Altissimo, Matteo [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Bellutti, Pierluigi [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Bertuccio, Giuseppe [Politecnico di Milano, Via Anzani 42, Como 22100 (Italy); INFN Milano, Via Celoria 16, Milano 20133 (Italy); Borghes, Roberto [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Carrato, Sergio [University of Trieste, Piazzale Europa 1, Trieste 34127 (Italy); Cautero, Giuseppe [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Fabiani, Sergio [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Giacomini, Gabriele [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Giuressi, Dario [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Kourousias, George [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Menk, Ralf Hendrik [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Picciotto, Antonino; Piemonte, Claudio [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Rachevski, Alexandre [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); and others

    2016-04-21

    The last decades have witnessed substantial efforts in the development of several detector technologies for X-ray fluorescence (XRF) applications. In spite of the increasing trend towards performing, cost-effective and reliable XRF systems, detectors for soft X-ray spectroscopy still remain a challenge, requiring further study, engineering and customization in order to yield effective and efficient systems. In this paper we report on the development, first characterization and tests of a novel multielement detector system based on low leakage current silicon drift detectors (SDD) coupled to ultra low noise custom CMOS preamplifiers for synchrotron-based low energy XRF. This new system exhibits the potential for improving the count rate by at least an order of magnitude resulting in ten-fold shorter dwell time at an energy resolution similar to that of single element silicon drift detectors.

  15. Investigation by laser induced breakdown spectroscopy, X-ray fluorescence and X-ray powder diffraction of the chemical composition of white clay ceramic tiles from Veliki Preslav

    Science.gov (United States)

    Blagoev, K.; Grozeva, M.; Malcheva, G.; Neykova, S.

    2013-01-01

    The paper presents the results of the application of laser induced breakdown spectroscopy, X-ray fluorescence spectrometry, and X-ray powder diffraction in assessing the chemical and phase composition of white clay decorative ceramic tiles from the medieval archaeological site of Veliki Preslav, a Bulgarian capital in the period 893-972 AC, well-known for its original ceramic production. Numerous white clay ceramic tiles with highly varied decoration, produced for wall decoration of city's churches and palaces, were found during the archaeological excavations in the old capital. The examination of fourteen ceramic tiles discovered in one of the city's monasteries is aimed at characterization of the chemical profile of the white-clay decorative ceramics produced in Veliki Preslav. Combining different methods and comparing the obtained results provides complementary information regarding the white-clay ceramic production in Veliki Preslav and complete chemical characterization of the examined artefacts.

  16. First combined total reflection X-ray fluorescence and grazing incidence X-ray absorption spectroscopy characterization of aeolian dust archived in Antarctica and Alpine deep ice cores

    Energy Technology Data Exchange (ETDEWEB)

    Cibin, G. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxon OX110DE (United Kingdom); IMONT/EIM, Ente Italiano della Montagna, P.za dei Caprettari 70, 00176 Roma (Italy); Universita' degli Studi di Roma Tre, Dipartimento di Scienze Geologiche, L.go S. Leonardo Murialdo 1, 00146 Roma (Italy)], E-mail: giannantonio.cibin@diamond.ac.uk; Marcelli, A. [INFN - Laboratori Nazionali di Frascati, P.O. Box 13, 00044 Frascati (Roma) (Italy); Maggi, V. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Sala, M. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Universita degli Studi di Milano, Dipartimento di Scienze della Terra ' A. Desio' , Sez. Mineralogia, Via Mangiagalli 34, 20133 Milano (Italy); Marino, F.; Delmonte, B. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Albani, S. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Universita degli Studi di Siena, Dottorato in Scienze Polari, via Laterina 8, 53100 Siena (Italy); Pignotti, S. [IMONT/EIM, Ente Italiano della Montagna, P.za dei Caprettari 70, 00176 Roma (Italy)

    2008-12-15

    Aeolian mineral dust archived in polar and mid latitude ice cores represents a precious proxy for assessing environmental and climatic variations at different timescales. In this respect, the identification of dust mineralogy plays a key role. In this work we performed the first preliminary X-ray absorption spectroscopy (XAS) experiments on mineral dust particles extracted from Antarctic and from Alpine firn cores using grazing incidence geometry at the Fe K-edge. A dedicated high vacuum experimental chamber was set up for normal-incidence and total-reflection X-Ray Fluorescence and Absorption Spectroscopy analyses on minor amounts of mineral materials at the Stanford Synchrotron Radiation Laboratory. Results show that this experimental technique and protocol allows recognizing iron inclusion mineral fraction on insoluble dust in the 1-10 {mu}g range.

  17. The Bionanoprobe: hard X-ray fluorescence nanoprobe with cryogenic capabilities

    Science.gov (United States)

    Chen, S.; Deng, J.; Yuan, Y.; Flachenecker, C.; Mak, R.; Hornberger, B.; Jin, Q.; Shu, D.; Lai, B.; Maser, J.; Roehrig, C.; Paunesku, T.; Gleber, S. C.; Vine, D. J.; Finney, L.; VonOsinski, J.; Bolbat, M.; Spink, I.; Chen, Z.; Steele, J.; Trapp, D.; Irwin, J.; Feser, M.; Snyder, E.; Brister, K.; Jacobsen, C.; Woloschak, G.; Vogt, S.

    2014-01-01

    Hard X-ray fluorescence microscopy is one of the most sensitive techniques for performing trace elemental analysis of biological samples such as whole cells and tissues. Conventional sample preparation methods usually involve dehydration, which removes cellular water and may consequently cause structural collapse, or invasive processes such as embedding. Radiation-induced artifacts may also become an issue, particularly as the spatial resolution increases beyond the sub-micrometer scale. To allow imaging under hydrated conditions, close to the ‘natural state’, as well as to reduce structural radiation damage, the Bionanoprobe (BNP) has been developed, a hard X-ray fluorescence nanoprobe with cryogenic sample environment and cryo transfer capabilities, dedicated to studying trace elements in frozen-hydrated biological systems. The BNP is installed at an undulator beamline at sector 21 of the Advanced Photon Source. It provides a spatial resolution of 30 nm for two-dimensional fluorescence imaging. In this first demonstration the instrument design and motion control principles are described, the instrument performance is quantified, and the first results obtained with the BNP on frozen-hydrated whole cells are reported. PMID:24365918

  18. Current status of the studies of biological objects by the time-resolved X-ray diffraction technique

    Energy Technology Data Exchange (ETDEWEB)

    Aul' chenko, V.M. [Budker Institute of Nuclear Physics, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Bukin, M.A. [Budker Institute of Nuclear Physics, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Vazina, A.A. [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino (Russian Federation); Gadzhiev, A.M. [Karaev Institute of Physiology, National Academy of Sciences of Azerbaijan, AzNas, 2, Sharifzade str., Baku, AZ1100 Azerbaijan (Azerbaijan)]. E-mail: agadzhiev@bakinter.net; Korneev, B.N. [Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino (Russian Federation); Sergienko, P.M. [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino (Russian Federation); Titov, V.M. [Budker Institute of Nuclear Physics, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Tolochko, B.P. [Institute of Solid State Chemistry and Mechanochemistry, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Sheromov, M.A. [Budker Institute of Nuclear Physics, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2005-05-01

    The methodological and technical aspects of the biological objects study by the time-resolved X-ray diffraction technique are described with reference to muscle contraction. The results of relevant investigations into the structural dynamics of a living muscle during its contraction are presented.

  19. Analysis of the Peiting Woman Using Portable X-Ray Fluorescence Spectroscopy

    Directory of Open Access Journals (Sweden)

    Bauerochse, Andreas

    2013-04-01

    Full Text Available Portable X-ray Fluorescence Spectroscopy was applied to the skeletal remains of 13 bog bodies and their bog burial environments. The objective was to create a better understanding of Northern European bog environmental chemistry and its diagenetic effects on interred bog bodies, determine bog body geographic disparity and/or origin, and identify if post-discovery preservation procedures were applied to the bog body remains. This paper summarizes the findings for one of those 13 bog bodies: the Peiting Woman from Bavaria, Germany. The elements analyzed include Antimony, Cobalt, Copper, Iron, Manganese, Molybdenum, Lead, Strontium, Titanium, Zinc, and Zirconium.

  20. Mapping element distributions in plant tissues using synchrotron X-ray fluorescence techniques.

    Science.gov (United States)

    Donner, Erica; de Jonge, Martin D; Kopittke, Peter M; Lombi, Enzo

    2013-01-01

    Synchrotron-based X-ray fluorescence (XRF) is allowing substantial advances in several disciplines of plant science by allowing the in situ examination of elements within plant tissues. Continual improvements in detector speed, sensitivity, and resolution are increasing the diversity of questions that can be addressed using this technique, including the in situ analysis of elements (such as nutrients or toxicants) within fresh and hydrated tissues. Here, we describe the general principles for designing and conducting experiments for the examination of elemental distributions in plant material using micro-XRF.

  1. Picoliter solution deposition for total reflection X-ray fluorescence analysis of semiconductor samples

    Energy Technology Data Exchange (ETDEWEB)

    Sparks, Chris M., E-mail: chris.sparks@svtc.co [Analytical Services, SVTC Technologies, Austin, TX 78741 (United States); Fittschen, Ursula E.A. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Institute of Inorganic and Applied Chemistry, University of Hamburg, 20146 Hamburg (Germany); Havrilla, George J. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2010-09-15

    A deposition system capable of delivering picoliter quantities of solution in programmable arrays was investigated as a method for sample preparation for total reflection X-ray fluorescence (TXRF) spectroscopy. Arrays of trace metals in solution were deposited on Si wafers. The array deposits provide a capability of depositing closely spaced (100 {mu}m or less), typically 5-20 {mu}m diameter droplets in an area that can be matched to the analysis spot of the TXRF detector. The dried depositions were physically characterized and the effect of deposition type and matrix on the TXRF signal was investigated.

  2. Elemental analysis of various biomass solid fractions in biorefineries by X-ray fluorescence spectrometry

    DEFF Research Database (Denmark)

    Le, Duy Michael; Sorensen, Hanne R.; Meyer, Anne S.

    2017-01-01

    Elemental analysis by X-ray fluorescence spectrometry (XRF) of solid samples from a biorefinery process was performed to study the behaviour of mineral elements in a process involving hydrothermal pretreatment of biomass (wheat straw, corn stover, sugarcane bagasse, palm oil empty fruit bunches......, poplar) followed by enzymatic hydrolysis and fermentation. For all the different biomasses, the biorefinery process concentrated silicon, aluminium, and calcium in the solid fraction, while potassium and magnesium were solubilised in the process and removed from the solid fraction. Sodium concentrations...

  3. Determination of metals in lubricating oils by X-ray fluorescence spectrometry.

    Science.gov (United States)

    Pouzar, M; Cernohorský, T; Krejcová, A

    2001-06-21

    The determination of common wear metals, namely iron, chromium, copper, zinc and lead, in a wide range of lubricating oil samples was investigated for the use of a low-cost, wavelength-dispersive X-ray fluorescence spectrometer. The procedure provided results in satisfactory agreement with inductively coupled plasma spectrometry used as reference method after microwave digestion of the samples in concentrated nitric acid. Statistical tests following extensive regression analyses of the data indicated that interelement effects were not statistically significant and that a simple linear regression was adequate for the calibration of individual metals.

  4. Twin image removal in X-ray fluorescence holography with two energies

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In the last decade,X-ray fluorescence holography has been developed for the study of 3D atomic arrangements in solids.However,it encounters the twin image problem which may disturb the reconstructed atomic images.In this paper,the formation of twin image is discussed and we propose a modified two-energy algorithm to remove the twin image.The simulation shows that the method is valid and more efficient than the multiple-energy algorithm proposed by Barton.

  5. Use of X-ray Fluorescence Analysis for the Determination of Rare Earth Elements

    Science.gov (United States)

    Schramm, Rainer

    2016-09-01

    X-ray fluorescence spectrometry (XRF) is a powerful tool for the analysis of solid material. That is the reason why the technique was applied for the determination of rare earth elements (REEs) since about 1970. At present, energy-dispersive XRF and wavelength-dispersive XRF are used for the analysis of pressed powder pellets or fused Li-borate beads containing REEs. The production of reliable results can only be achieved by careful optimization of the parameter, in particular the selection of spectral lines. The quantification is based on a calibration realized by using reference samples.

  6. Chemical characterization of clay SRM by X-ray fluorescence – results comparison from different laboratories

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Appoloni

    2009-03-01

    Full Text Available Two Energy Dispersive X-ray Fluorescence equipments have been compared in order to verify its performance for clay characterization and potential application to the study in archaeometric field and industry. Two clay standard reference materials (SRM, IPT-42 and IPT-51 and one IAEA intercomparison sample were analyzed by two different methodologies and equipments. Asentamiento Universitario Zapala laboratory has a Shimadzu EDX-800HS bench top equipment and 13 elements from S to Zr were quantified in the standards. Applied Nuclear Physics Laboratory has a portable EDXRF system. It was possible to quantify K, Ti and Fe and qualitatively to identify Mn, Rb, Zn and Zr.

  7. X-Ray fluorescence analysis of trace elements in fruit juice

    Science.gov (United States)

    Bao, Sheng-Xiang; Wang, Zhi-Hong; Liu, Jing-Song

    1999-12-01

    X-Ray fluorescence spectrometry is applied to the determination of trace elements in fruit juice characterized by a high content of sugar and other soluble solid substances. Samples are prepared by evaporation, carbonization and pressing into discs. The synthesis of standards is described in detail. All element concentrations are directly estimated from linear calibration curves obtained without any matrix correction. The results of the analysis are in good agreement with those given by inductively coupled plasma-atomic emission spectrometry and atomic absorption spectrometry techniques.

  8. An x-ray fluorescence study of lake sediments from ancient Turkey using synchrotron radiation.

    Energy Technology Data Exchange (ETDEWEB)

    Alatas, A.; Alp, E. E.; Friedman, E. S.; Jennings, G.; Johnson, C. E.; Lai, B.; Mini, S. M.; Sato, Y.; Wilkinson, T. J.; Yener, K. A.

    1999-03-10

    Sediments from relic Lake Golbasi were analyzed by X-ray fluorescence with synchrotrons radiation to determine changes in element concentrations over time with selected elements serving as proxies for environmental change. Increases in Ca and Sr suggest soil formation during a dry period, from ca. 4500 BC to ca. 200 AD at which point K, Rb, Zr, Ti, and Y increase, indicating the return of a wet environment. Soil erosion, represented by Cr and Ni, increases ca. 7000 BC, probably as a consequence of environmental change, prior to suggested exploitation of natural resources by the newly urbanized society of the third millennium BC.

  9. Waste reduction and process improvements in the analysis of plutonium by x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Worley, Christopher G [Los Alamos National Laboratory; Sodweberg, Constance B [Los Alamos National Laboratory; Townsend, Lisa E [Los Alamos National Laboratory

    2009-01-01

    Significant modifications were made to a sample preparation process for quantifying gallium in plutonium metal by wavelength dispersive X-ray fluorescence. These changes were made to minimize waste and improve process safety and efficiency. Sample sizes were reduced, cheaper sample preparation acids were used, and safety improvements were implemented. Using this modified process, results from analyzing a batch oftest samples indicated that relative precision and accuracy were {approx}0.2% and {approx}0.1% respectively, which is comparable to that obtained using the older, established sample preparation method.

  10. Application of direct peak analysis to energy dispersive x-ray fluorescence spectra

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, K.K.

    1977-07-01

    A modified Covell method for direct peak analysis has been applied to energy dispersive x-ray fluorescence spectra. The method is background independent and is well-suited to computerized data reduction. It provides acceptable precision, minimizes errors from instrumental gain shift, and permits peak overlap correction. Peak overlap errors exhibit both positive and negative nodes as a function of peak separation distance, and are corrected using concentration ratios determined from thin, single-element standards. Peak precisions and overlaps are evaluated as a function of window width to aid in width selection. Least-square polynomial smoothing prior to peak analysis significantly improves peak area precisions without significantly affecting their accuracies.

  11. A Fundamental Parameter-Based Calibration Model for an Intrinsic Germanium X-Ray Fluorescence Spectrometer

    DEFF Research Database (Denmark)

    Christensen, Leif Højslet; Pind, Niels

    1982-01-01

    secondary target a number of relative calibration constants are calculated on the basis of knowledge of the irradiation geometry, the detector specifications, and tabulated fundamental physical parameters. The absolute calibration of the spectrometer is performed by measuring one pure element standard per......A matrix-independent fundamental parameter-based calibration model for an energy-dispersive X-ray fluorescence spectrometer has been developed. This model, which is part of a fundamental parameter approach quantification method, accounts for both the excitation and detection probability. For each...

  12. Confocal X-ray fluorescence spectrometer for in-situ analyses of paintings

    Science.gov (United States)

    Trojek, Tomáš; Prokeš, Radek; Šefců, Radka; Bilavčíková, Hana; Čechák, Tomáš

    2017-08-01

    This paper describes the properties of the newly constructed device for confocal X-ray fluorescence analysis that was tested with a sample plate consisting of 19 combinations of two single pigment layers. The preparation of this experimental wooden board with layered systems was based on knowledge of the panel painting techniques of Bohemian collections from the National Gallery in Prague dating back to the 14th and 15th centuries. The design of the confocal setup allows its transport and the in-situ measurement of paintings in depositories or even in exhibition areas. The advantages of our confocal setup with movable collimating optics are also described.

  13. X-ray fluorescence spectrometry determination of open-hearth furnace slag by pressed powder briquetting

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A rapid analysis method of determining content of eight compounds of open-hearth furnace slag was developed using X-ray fluorescence spectrometry and pressed powder briquettes. Matrix effect was corrected using theoretical alpha coefficient. Grains-size effect was eliminated by optimized sample preparation technique parameters. Mineral effect was corrected with standard curve of specially made standard samples. The analysis results of TiO2, TFe, SiO2, MgO, Al2O3,CaO, MnO and P2O5 in slag samples showed that both precision and accuracy are comparable with that of chemical method.

  14. Electrophoretic separation and detection of metalloproteins by X-ray fluorescence mapping.

    Science.gov (United States)

    Khare, Tripti; Chishti, Yasmin; Finney, Lydia A

    2012-01-01

    All living systems depend on metalloproteins. Yet, while tools for the separation and identification of apo-proteins are well developed, those enabling identification and quantitation of individual metalloproteins within complex mixtures are still nascent. Here, we describe the electrophoretic separation of a mixture of carbonic anhydrase, ceruloplasmin, urease, and hemoglobin using native 2D gel electrophoresis and X-ray fluorescence mapping-an approach we have developed to be broadly applicable, not require specialized equipment for sample preparation, and likely to be extensible in the future.

  15. Synchrotron total reflection X-ray fluorescence at BL-16 microfocus beamline of Indus-2

    Science.gov (United States)

    Tiwari, M. K.; Singh, A. K.; Das, Gangadhar; Chowdhury, Anupam; Lodha, G. S.

    2014-04-01

    Determination of ultra trace elements is important in many disciplines both in basic and applied sciences. Numerous applications show their importance in medical science, environmental science, materials science, food processing and semiconductor industries and in maintaining the quality control of ultra pure chemicals and reagents. We report commissioning of a synchrotron based total reflection x-ray fluorescence (TXRF) facility on the BL-16 microfocus beamline of Indus-2. This paper describes the performance of the BL-16 TXRF spectrometer and the detailed description of its capabilities through examples of measured results.

  16. First Total Reflection X-Ray Fluorescence round-robin test of water samples: Preliminary results

    Science.gov (United States)

    Borgese, Laura; Bilo, Fabjola; Tsuji, Kouichi; Fernández-Ruiz, Ramón; Margui, Eva; Streli, Christina; Pepponi, Giancarlo; Stosnach, Hagen; Yamada, Takashi; Vandenabeele, Peter; Maina, David M.; Gatari, Michael; Shepherd, Keith D.; Towett, Erick K.; Bennun, Leonardo; Custo, Graciela; Vasquez, Cristina; Depero, Laura E.

    2014-11-01

    Total Reflection X-Ray Fluorescence (TXRF) is a mature technique to evaluate quantitatively the elemental composition of liquid samples deposited on clean and well polished reflectors. In this paper the results of the first worldwide TXRF round-robin test of water samples, involving 18 laboratories in 10 countries are presented and discussed. The test was performed within the framework of the VAMAS project, interlaboratory comparison of TXRF spectroscopy for environmental analysis, whose aim is to develop guidelines and a standard methodology for biological and environmental analysis by means of the TXRF analytical technique.

  17. Portable X-ray fluorescence spectrometer system using a low-level radioisotope {sup 55}Fe

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyama, Susumu [Kibi International Univ., Takahashi, Okayama (Japan); Noda, Yasuko [Den Material Co., Ltd., Color Material Research Laboratory, Atsugi, Kanagawa (Japan); Kuchitsu, Nobuaki [Independent Administrative Institution National Research Institute for Cultural Properties, Tokyo (Japan)

    2002-11-01

    It is well known that the detection of light elements is difficult using a portable X-ray fluorescence spectrometer with {sup 241}Am (1.85 MBq) as the radiation source. In this study, {sup 55}Fe (3.7 MBq) was used as the radiation source instead of {sup 241}Am, and the beryllium cover of the detector window was thinned in order to increase the sensitivity. As a result, light elements from Si to K could be identified by the investigated method. This method will be effective to specify mineral pigments of mural paintings. (author)

  18. Implementation of the phenomenon of total reflection for total reflection X-Ray fluorescence spectrometry technique simulation

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Marcio H. dos; Anjos, Marcelino J. dos; Oliveira, Luis F. de, E-mail: marciohsantos2010@gmail.com, E-mail: bmarcelin@uerj.br, E-mail: clfolive@uerj.br [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Programa de Pos-Graduacao em Fisica; Albuquerque, Marcelo P. de, E-mail: mpalbuquer@gmail.com [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Atividades Tecnicas

    2015-07-01

    Within the scientific research field, X-ray fluorescence spectrometry is a basic technique for chemical analysis of materials, allowing recognition and study of the elemental nature of a particular sample. With this technique, the researcher uses different devices such as X-ray tubes, radioactive sources, monochromators crystals, capillaries, slits and waveguides, Si-Li detectors and scintillators. Furthermore, one can provide these elements with different arrangements in order to obtain a better configuration. One of the X-ray fluorescence spectrometry variants is the total reflection X-ray fluorescence spectrometry. It is based on the optical phenomenon of total reflection observed when a radiation beam impinges on a surface below a critical angle. Two important characteristics of this technique are to minimize the generation of background derived from the reflector support and allow the radiation interaction with very thin samples (thickness between 100 nm and 15 μm). The goal of the paper is to show the computational modeling of the physical phenomenon of total reflection that enables the implementation of total reflection X-ray fluorescence spectrometry technique through the simulator developed at Institute of Physics of the University of the State of Rio de Janeiro with parallel and distributed processing features. The simulator at hand is already available for implementation of energy dispersive X-ray fluorescence spectrometry. Through it, they are shown three simulations, each based on a particular apparatus: a set of reflectors, a capillary and a waveguide with lucite reflectors. (author)

  19. Shedding new light on historical metal samples using micro-focused synchrotron X-ray fluorescence and spectroscopy

    Science.gov (United States)

    Grolimund, D.; Senn, M.; Trottmann, M.; Janousch, M.; Bonhoure, I.; Scheidegger, A. M.; Marcus, M.

    2004-10-01

    Synchrotron-based micro-X-ray fluorescence (micro-XRF) and micro-X-ray absorption spectroscopy (micro-XAS) were used in the present study to obtain spatially resolved micro-scale information on elemental composition, trace element distribution, chemical speciation and oxidation state and/or mineral phase distribution within historical iron artefacts dating from the Iron Age to early Medieval Times. Large area two-dimensional trace element distribution maps and oxidation state maps with micrometer spatial resolution were required to answer open archaeological questions in the context of ancient metal processing. The first set of examples was focusing on historical weapons and included two ancient iron sword blades. The micro-XRF maps revealed a distinct, highly correlated distribution pattern of trace elements such as As, Ni, Cu and Zn. Accordingly, the number of used raw materials could be determined unambiguously and key information concerning the used ancient smithing technique were gained. Further, the ability to record—in a fast manner—large area maps with high spatial resolution ('elemental screening') led to the discovery of a hitherto unknown enhanced occurrence of selected trace elements (Cu, Zn, and Au) at the blade surface. Complementary investigations by high resolution scanning electron microscopy were able to localize these trace metals within a carbon-rich matrix may be pointing towards an artifact induced during preservation. A second set of investigated artefacts is dealing with smithing waste products and related historical processing techniques and conditions. Synchrotron-based micro-XRF and micro-XAS were used to determine the structural composition as well as the spatial variation of the predominant Fe oxidation state and corresponding crystallographic phases. The study revealed the presence of distinct domains of Fe 0, Fe IIO (wustite), and α-Fe IIIOOH (goethite), separated by sharp domain boundaries. These findings help to gain new

  20. Time-Resolved X-Ray Diffraction: The Dynamics of the Chemical Bond

    DEFF Research Database (Denmark)

    Møller, Klaus Braagaard; Henriksen, Niels Engholm

    2012-01-01

    We review the basic theoretical formulation for pulsed X-ray scattering on nonstationary molecular states. Relevant time scales are discussed for coherent as well as incpherent X-ray pulses. The general formalism is applied to a nonstationary diatomic molecule in order to highlight the relation b...

  1. Quantitative analysis of intermediately and infinitely thick samples with thin sample approach without sample preparation using confocal X-ray fluorescence

    CERN Document Server

    Sun, Xue-Peng; Sun, Tian-Xi; Peng, Song; Sun, Wei-Yuan; Li, Fang-Zuo; Jiang, Bo-Wen; Ma, Yong-Zhong; Ding, Xun-Liang

    2015-01-01

    In order to validate that the confocal X-ray fluorescence had potential applications in analyzing the intermediately and infinitely thick samples with thin sample approach without sample preparations, as an example, the confocal X-ray fluorescence based on polycapillary X-ray optics was used to analyze multi elements solutions.

  2. ERICA: an energy resolving photon counting readout ASIC for X-ray in-line cameras

    Science.gov (United States)

    Macias-Montero, J.-G.; Sarraj, M.; Chmeissani, M.; Moore, T.; Casanova, R.; Martinez, R.; Puigdengoles, C.; Prats, X.; Kolstein, M.

    2016-12-01

    We present ERICA (Energy Resolving Inline X-ray Camera) a photon-counting readout ASIC, with 6 energy bins. The ASIC is composed of a matrix of 8 × 20 pixels controlled by a global digital controller and biased with 7 independent digital to analog converters (DACs) and a band-gap current reference. The pixel analog front-end includes a charge sensitive amplifier with 16 mV/ke- gain and dynamic range of 45 ke-. ERICA has programmable pulse width, an adjustable constant current feedback resistor, a linear test pulse generator, and six discriminators with 6-bit local threshold adjustment. The pixel digital back-end includes the digital controller, 8 counters of 8-bit depth, half-full buffer flag for any of the 8 counters, a 74-bit shadow/shift register, a 74-bit configuration latch, and charge sharing compensation processing to perform the energy classification and counting operations of every detected photon in 1 μ s. The pixel size is 330 μm × 330 μm and its average consumption is 150 μW. Implemented in TSMC 0.25 μm CMOS process, the ASIC pixel's equivalent noise charge (ENC) is 90 e- RMS connected to a 1 mm thickness matching CdTe detector biased at -300 V with a total leakage current of 20 nA.

  3. Cavitation dynamics on a NACA0015 hydrofoil using time resolved X-ray densitometry

    Science.gov (United States)

    Ganesh, Harish; Wu, Juliana; Ceccio, Steven

    2015-11-01

    Recent investigations of partial cavitation have shown that the transition from stable to shedding cavities can be related to the presence of both propagating bubbly shocks and re-entrant liquid jets originating in the cavity closure region. In the present study, formation of sheet cavitation and its transition to periodically shedding cavities is studied on a NACA0015 hydrofoil in a recirculating water tunnel at different attack angles. Using high-speed videos and time resolved X-ray densitometry, the instantaneous void fraction flow fields are obtained to identify the principal mechanism responsible for transition from stable to shedding cavities over a range of attack angles and cavitation numbers. The role of attack angle is of particular interest, since is it related to the pressure gradient at cavity enclosure, and can lead to the formation of stronger reentrant flows. The relative importance of reentrant liquid flow and bubbly shock wave propagation will be discussed This work is supported by Office of Naval Research.

  4. Pore-scale evaporation-condensation dynamics resolved by synchrotron x-ray tomography

    Science.gov (United States)

    Shahraeeni, Ebrahim; Or, Dani

    2012-01-01

    Capillary processes greatly influence vapor mediated transport dynamics and associated changes in liquid phase content of porous media. Rapid x-ray synchrotron tomography measurements were used to resolve liquid-vapor interfacial dynamics during evaporation and condensation within submillimetric pores forming between sintered glass bead samples subjected to controlled ambient temperature and relative humidity. Evolution of gas-liquid interfacial shapes were in agreement with predictions based on our analytical model for interfacial dynamics in confined wedge-shaped pores. We also compared literature experimental data at the nanoscale to illustrate the capability of our model to describe early stages of condensation giving rise to the onset of capillary forces between rough surfaces. The study provides high resolution, synchrotron-based observations of capillary evaporation-condensation dynamics at the pore scale as the confirmation of the pore scale analytical model for capillary condensation in a pore and enables direct links with evolution of macroscopic vapor gradients within a sintered glass bead sample through their effect on configuration and evolution of the local interfaces. Rapid condensation processes play a critical role in the onset of capillary-induced friction affecting mechanical behavior of physical systems and industrial applications.

  5. Sub-100-ps structural dynamics of horse heart myoglobin probed by time-resolved X-ray solution scattering

    Science.gov (United States)

    Oang, Key Young; Kim, Kyung Hwan; Jo, Junbeom; Kim, Youngmin; Kim, Jong Goo; Kim, Tae Wu; Jun, Sunhong; Kim, Jeongho; Ihee, Hyotcherl

    2015-01-01

    Here we report sub-100-ps structural dynamics of horse heart myoglobin revealed by time-resolved X-ray solution scattering. By applying the time-slicing scheme to the measurement and subsequent deconvolution, we investigate the protein structural dynamics that occur faster than the X-ray temporal pulse width of synchrotrons (~100 ps). The singular value decomposition analysis of the experimental data suggests that two structurally distinguishable intermediates are formed within 100 ps. In particular, the global structural change occurring on the time scale of 70 ps is identified. PMID:25678733

  6. Visualizing a protein quake with time-resolved X-ray scattering at a free-electron laser

    DEFF Research Database (Denmark)

    Arnlund, David; Johansson, Linda C.; Wickstrand, Cecilia;

    2014-01-01

    We describe a method to measure ultrafast protein structural changes using time-resolved wide-angle X-ray scattering at an X-ray free-electron laser. We demonstrated this approach using multiphoton excitation of the Blastochloris viridis photosynthetic reaction center, observing an ultrafast global...... conformational change that arises within picoseconds and precedes the propagation of heat through the protein. This provides direct structural evidence for a 'protein quake': the hypothesis that proteins rapidly dissipate energy through quake-like structural motions....

  7. Characterization of spatially resolved high resolution x-ray spectrometers for high energy density physics and light source experiments.

    Science.gov (United States)

    Hill, K W; Bitter, M; Delgado-Aparacio, L; Efthimion, P; Pablant, N A; Lu, J; Beiersdorfer, P; Chen, H; Magee, E

    2014-11-01

    A high resolution 1D imaging x-ray spectrometer concept comprising a spherically bent crystal and a 2D pixelated detector is being optimized for diagnostics of small sources such as high energy density physics (HEDP) and synchrotron radiation or x-ray free electron laser experiments. This instrument is used on tokamak experiments for Doppler measurements of ion temperature and plasma flow velocity profiles. Laboratory measurements demonstrate a resolving power, E/ΔE of order 10,000 and spatial resolution better than 10 μm. Initial tests of the high resolution instrument on HEDP plasmas are being performed.

  8. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS

    Energy Technology Data Exchange (ETDEWEB)

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2006-05-08

    Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence (XRF) spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop XRF analytical methods that provide the rapid turnaround time (<8 hours) requested by the WTP, while providing sufficient accuracy and precision to determine waste composition variations. For Phase 1a, SRNL (1) evaluated, selected, and procured an XRF instrument for WTP installation, (2) investigated three XRF sample methods for preparing the LAW sub-sample for XRF analysis, and (3) initiated scoping studies on AN-105 (Envelope A) simulant to determine the instrument's capability, limitations, and optimum operating parameters. After preliminary method development on simulants and the completion of Phase 1a activities, SRNL received approval from WTP to begin Phase 1b activities with the objective of optimizing the XRF methodology. Three XRF sample methods used for preparing the LAW sub-sample for XRF analysis were studied: direct liquid analysis, dried spot, and fused glass. The direct liquid method was selected because its major advantage is that the LAW can be analyzed directly without any sample alteration that could bias the method accuracy. It also is the fastest preparation technique--a typical XRF measurement could be completed in < 1hr after sample delivery. Except for sodium, the method detection limits (MDLs) for the most important analytes in solution, the hold point elements, were achieved by this method. The XRF detection limits are generally adequate for glass former batching and product composition reporting, but may be inadequate for some species (Hg, Cd, and Ba) important

  9. Magnetic dichroism in angular resolved hard X-ray photoelectron spectroscopy from buried magnetic layers

    Energy Technology Data Exchange (ETDEWEB)

    ViolBarbosa, Carlos E.; Ouardi, Siham [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden (Germany); Fecher, Gerhard H., E-mail: fecher@cpfs.mpg.de [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden (Germany); Ebke, Daniel; Felser, Claudia [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden (Germany)

    2013-08-15

    Highlights: ► We show the feasibility of angular resolved MCD in photospectroscopy. ► Wide-acceptance lens system allows a fixed incident light angle in the experiment. ► Bulk-sensitive HAXPES-MCDAD was used to study buried layers. ► Performance tools as Scalasca and Paraver are used to debug the applications. -- Abstract: This work reports on the measurement of magnetic dichroism in angular-resolved photoelectron spectroscopy from in-plane magnetized buried thin films. The high bulk sensitivity of hard X-ray photoelectron spectroscopy (HAXPES) in combination with circularly polarized radiation enables the investigation of the magnetic properties of buried layers. Angular distributions of high kinetic energy (7–8 keV) photoelectrons in a range of about 60° were recorded in parallel to the energy distribution. Depending on purpose, energy and angular resolutions of 150–250 meV and 0.17–2° can be accomplished simultaneously in such experiments. Experiments were performed on exchange-biased magnetic layers covered by thin oxide films. More specifically, the angular distribution of photoelectrons from the ferromagnetic layer Co{sub 2}FeAl layer grown on MnIr exchange-biasing layer was investigated where the magnetic structure is buried beneath a MgO layer. Pronounced magnetic dichroism is found in the Co and Fe 2p states for all angles of emission. A slightly increased magnetic dichroism was observed for normal emission in agreement with theoretical considerations.

  10. Combined evaluation of grazing incidence X-ray fluorescence and X-ray reflectivity data for improved profiling of ultra-shallow depth distributions

    Science.gov (United States)

    Ingerle, D.; Meirer, F.; Pepponi, G.; Demenev, E.; Giubertoni, D.; Wobrauschek, P.; Streli, C.

    2014-09-01

    The continuous downscaling of the process size for semiconductor devices pushes the junction depths and consequentially the implantation depths to the top few nanometers of the Si substrate. This motivates the need for sensitive methods capable of analyzing dopant distribution, total dose and possible impurities. X-ray techniques utilizing the external reflection of X-rays are very surface sensitive, hence providing a non-destructive tool for process analysis and control. X-ray reflectometry (XRR) is an established technique for the characterization of single- and multi-layered thin film structures with layer thicknesses in the nanometer range. XRR spectra are acquired by varying the incident angle in the grazing incidence regime while measuring the specular reflected X-ray beam. The shape of the resulting angle-dependent curve is correlated to changes of the electron density in the sample, but does not provide direct information on the presence or distribution of chemical elements in the sample. Grazing Incidence XRF (GIXRF) measures the X-ray fluorescence induced by an X-ray beam incident under grazing angles. The resulting angle dependent intensity curves are correlated to the depth distribution and mass density of the elements in the sample. GIXRF provides information on contaminations, total implanted dose and to some extent on the depth of the dopant distribution, but is ambiguous with regard to the exact distribution function. Both techniques use similar measurement procedures and data evaluation strategies, i.e. optimization of a sample model by fitting measured and calculated angle curves. Moreover, the applied sample models can be derived from the same physical properties, like atomic scattering/form factors and elemental concentrations; a simultaneous analysis is therefore a straightforward approach. This combined analysis in turn reduces the uncertainties of the individual techniques, allowing a determination of dose and depth profile of the implanted

  11. Combined evaluation of grazing incidence X-ray fluorescence and X-ray reflectivity data for improved profiling of ultra-shallow depth distributions

    Energy Technology Data Exchange (ETDEWEB)

    Ingerle, D., E-mail: dingerle@ati.ac.at [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria); Meirer, F. [Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (Netherlands); Pepponi, G.; Demenev, E.; Giubertoni, D. [MiNALab, CMM-irst, Fondazione Bruno Kessler, Via Sommarive 18, I-38050 Povo (Italy); Wobrauschek, P.; Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria)

    2014-09-01

    The continuous downscaling of the process size for semiconductor devices pushes the junction depths and consequentially the implantation depths to the top few nanometers of the Si substrate. This motivates the need for sensitive methods capable of analyzing dopant distribution, total dose and possible impurities. X-ray techniques utilizing the external reflection of X-rays are very surface sensitive, hence providing a non-destructive tool for process analysis and control. X-ray reflectometry (XRR) is an established technique for the characterization of single- and multi-layered thin film structures with layer thicknesses in the nanometer range. XRR spectra are acquired by varying the incident angle in the grazing incidence regime while measuring the specular reflected X-ray beam. The shape of the resulting angle-dependent curve is correlated to changes of the electron density in the sample, but does not provide direct information on the presence or distribution of chemical elements in the sample. Grazing Incidence XRF (GIXRF) measures the X-ray fluorescence induced by an X-ray beam incident under grazing angles. The resulting angle dependent intensity curves are correlated to the depth distribution and mass density of the elements in the sample. GIXRF provides information on contaminations, total implanted dose and to some extent on the depth of the dopant distribution, but is ambiguous with regard to the exact distribution function. Both techniques use similar measurement procedures and data evaluation strategies, i.e. optimization of a sample model by fitting measured and calculated angle curves. Moreover, the applied sample models can be derived from the same physical properties, like atomic scattering/form factors and elemental concentrations; a simultaneous analysis is therefore a straightforward approach. This combined analysis in turn reduces the uncertainties of the individual techniques, allowing a determination of dose and depth profile of the implanted

  12. Combined evaluation of grazing incidence X-ray fluorescence and X-ray reflectivity data for improved profiling of ultra-shallow depth distributions☆

    Science.gov (United States)

    Ingerle, D.; Meirer, F.; Pepponi, G.; Demenev, E.; Giubertoni, D.; Wobrauschek, P.; Streli, C.

    2014-01-01

    The continuous downscaling of the process size for semiconductor devices pushes the junction depths and consequentially the implantation depths to the top few nanometers of the Si substrate. This motivates the need for sensitive methods capable of analyzing dopant distribution, total dose and possible impurities. X-ray techniques utilizing the external reflection of X-rays are very surface sensitive, hence providing a non-destructive tool for process analysis and control. X-ray reflectometry (XRR) is an established technique for the characterization of single- and multi-layered thin film structures with layer thicknesses in the nanometer range. XRR spectra are acquired by varying the incident angle in the grazing incidence regime while measuring the specular reflected X-ray beam. The shape of the resulting angle-dependent curve is correlated to changes of the electron density in the sample, but does not provide direct information on the presence or distribution of chemical elements in the sample. Grazing Incidence XRF (GIXRF) measures the X-ray fluorescence induced by an X-ray beam incident under grazing angles. The resulting angle dependent intensity curves are correlated to the depth distribution and mass density of the elements in the sample. GIXRF provides information on contaminations, total implanted dose and to some extent on the depth of the dopant distribution, but is ambiguous with regard to the exact distribution function. Both techniques use similar measurement procedures and data evaluation strategies, i.e. optimization of a sample model by fitting measured and calculated angle curves. Moreover, the applied sample models can be derived from the same physical properties, like atomic scattering/form factors and elemental concentrations; a simultaneous analysis is therefore a straightforward approach. This combined analysis in turn reduces the uncertainties of the individual techniques, allowing a determination of dose and depth profile of the implanted

  13. [Application of the racial algorithm in energy dispersive X-ray fluorescence overlapped spectrum analysis].

    Science.gov (United States)

    Zeng, Guo-Qiang; Luo, Yao-Yao; Ge, Liang-Quan; Zhang, Qing-Xian; Gu, Yi; Cheng, Feng

    2014-02-01

    In the energy dispersive X-ray fluorescence spectrum analysis, scintillation detector such as NaI (Tl) detector usually has a low energy resolution at around 8%. The low energy resolution causes problems in spectral data analysis especially in the high background and low counts condition, it is very limited to strip the overlapped spectrum, and the more overlapping the peaks are, the more difficult to peel the peaks, and the qualitative and quantitative analysis can't be carried out because we can't recognize the peak address and peak area. Based on genetic algorithm and immune algorithm, we build a new racial algorithm which uses the Euclidean distance as the judgment of evolution, the maximum relative error as the iterative criterion to be put into overlapped spectrum analysis, then we use the Gaussian function to simulate different overlapping degrees of the spectrum, and the racial algorithm is used in overlapped peak separation and full spectrum simulation, the peak address deviation is in +/- 3 channels, the peak area deviation is no more than 5%, and it is proven that this method has a good effect in energy dispersive X-ray fluorescence overlapped spectrum analysis.

  14. [Determination of major elements in soil from cancer village by X-ray fluorescence spectrometry].

    Science.gov (United States)

    Wei, Zhen-Lin; Li, He; Rui, Yu-Kui

    2008-11-01

    Many social problems arise from environmental pollution, cancer village is one of the many important problems caused by pollution. The authors selected a typical cancer village where 80-100 people died of cancer in the last five years, but there are only a total of 1 200 people in this village. The authors sampled soils from crops-planted areas and detected the major elements by X-ray fluorescence spectrometry. The results showed that the contents of SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O and P2O5 in soil of this village were 66.05%, 0.66%, 11.37%, 3.93%, 0.075%, 1.97%, 5.47%, 1.90%, 2.11% and 0.20% respectively; with the precision being +/- 0.20%, +/- 0.005%, +/- 0.10%, +/- 0.10%, +/- 0.005%, +/- 0.05%, +/- 0.04%, +/- 0.08%, +/- 0.02% and +/- 0.005% respectively, which showed that X-ray fluorescence spectrometry is a good method.

  15. Direct analysis of biological samples by total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Lue M, Marco P. [Unidad de Analisis Instrumental, Departamento de Quimica y Suelos, Decanato de Agronomia, Universidad Centro-occidental Lisandro Alvarado, Apartado Postal 4076, Cabudare 3023 (Venezuela)]. E-mail: luemerumarco@yahoo.es; Hernandez-Caraballo, Edwin A. [Instituto Venezolano-Andino para la Investigacion Quimica (IVAIQUIM), Facultad de Ciencias, Universidad de los Andes, Merida 5101 (Venezuela)

    2004-08-31

    The technique of total reflection X-ray fluorescence (TXRF) is well suited for the direct analysis of biological samples due to the low matrix interferences and simultaneous multi-element nature. Nevertheless, biological organic samples are frequently analysed after digestion procedures. The direct determination of analytes requires shorter analysis time, low reactive consumption and simplifies the whole analysis process. On the other hand, the biological/clinical samples are often available in minimal amounts and routine studies require the analysis of large number of samples. To overcome the difficulties associated with the analysis of organic samples, particularly of solid ones, different procedures of sample preparation and calibration to approach the direct analysis have been evaluated: (1) slurry sampling, (2) Compton peak standardization, (3) in situ microwave digestion, (4) in situ chemical modification and (5) direct analysis with internal standardization. Examples of analytical methods developed by our research group are discussed. Some of them have not been previously published, illustrating alternative strategies for coping with various problems that may be encountered in the direct analysis by total reflection X-ray fluorescence spectrometry.

  16. Quantification of phosphorus in single cells using synchrotron X-ray fluorescence.

    Science.gov (United States)

    Núñez-Milland, Daliángelis R; Baines, Stephen B; Vogt, Stefan; Twining, Benjamin S

    2010-07-01

    Phosphorus is required for numerous cellular compounds and as a result can serve as a useful proxy for total cell biomass in studies of cell elemental composition. Single-cell analysis by synchrotron X-ray fluorescence (SXRF) enables quantitative and qualitative analyses of cell elemental composition with high elemental sensitivity. Element standards are required to convert measured X-ray fluorescence intensities into element concentrations, but few appropriate standards are available, particularly for the biologically important element P. Empirical P conversion factors derived from other elements contained in certified thin-film standards were used to quantify P in the model diatom Thalassiosira pseudonana, and the measured cell quotas were compared with those measured in bulk by spectrophotometry. The mean cellular P quotas quantified with SXRF for cells on Au, Ni and nylon grids using this approach were not significantly different from each other or from those measured spectrophotometrically. Inter-cell variability typical of cell populations was observed. Additionally, the grid substrates were compared for their suitability to P quantification based on the potential for spectral interferences with P. Nylon grids were found to have the lowest background concentrations and limits of detection for P, while background concentrations in Ni and Au grids were 1.8- and 6.3-fold higher. The advantages and disadvantages of each grid type for elemental analysis of individual phytoplankton cells are discussed.

  17. Applications of X-ray fluorescence holography to determine local lattice distortions

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Kouichi, E-mail: khayashi@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Happo, Naohisa [Graduate School of Information Sciences, Hiroshima City University, Hiroshima 731-3194 (Japan); Hosokawa, Shinya [Department of Physics, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan)

    2014-08-15

    Highlights: • We summarized topics of X-ray fluorescence holography focused on the local lattice distortions. • We found details of behaviors of nearest neighbor atoms around dopants. • We found the average distributions of the atoms at the individual sites in mixed crystals. • Distorted and undistorted sires sometimes coexist in a same mixed crystal. - Abstract: X-ray fluorescence holography (XFH) is a method for investigating atomic order up to the medium ranges, and can provide 3D atomic images around specific elements within a radius of nm order. In addition to these characteristics, XFH is sensitive to positional fluctuations of atoms, and therefore it is useful for characterizing the local lattice distortions around specific elements. We have applied XFH to dopants and mixed crystals. We found interesting features in local lattice distortions, such as the displacements of first-neighbor atoms around dopants, far-sighted views of the atomistic fluctuations in mixed crystals, and the coexistence of distorted/undistorted sites in the same material.

  18. Mapping Metal Elements of Shuangbai Dinosaur Fossil by Synchrotron X-ray Fluorescence Microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Qun, Y; Ablett, J

    2008-01-01

    The metal elements mapping of Shuangbai dinosaur fossil, was obtained by synchrotron x-ray fluorescence (SXRF). Eight elements, Ca, Mn, Fe, Cu, Zn, As, Y and Sr were determined. Elements As and Y were detected for the first time in the dinosaur fossil. The data indicated that metal elements are asymmetrical on fossil section. This is different from common minerals. Mapping metals showed that metal element As is few. The dinosaur most likely belongs to natural death. This is different from Zigong dinosaurs which were found dead from poisoning. This method has been used to find that metals Fe and Mn are accrete, and the same is true for Sr and Y. This study indicated that colloid granule Fe and Mn, as well as Sr and Y had opposite electric charges in lithification process of fossils. By this analysis, compound forms can be ascertained. Synchrotron light source x-ray fluorescence is a complementary method that shows mapping of metal elements at the dinosaur fossil, and is rapid, exact and intuitionist. This study shows that dinosaur fossil mineral imaging has a potential in reconstructing the paleoenvironment and ancient geology.

  19. Spectral Interferences Manganese (Mn) - Europium (Eu) Lines in X-Ray Fluorescence Spectrometry Spectrum

    Science.gov (United States)

    Tanc, Beril; Kaya, Mustafa; Gumus, Lokman; Kumral, Mustafa

    2016-04-01

    X-ray fluorescence (XRF) spectrometry is widely used for quantitative and semi quantitative analysis of many major, minor and trace elements in geological samples. Some advantages of the XRF method are; non-destructive sample preparation, applicability for powder, solid, paste and liquid samples and simple spectrum that are independent from chemical state. On the other hand, there are some disadvantages of the XRF methods such as poor sensitivity for low atomic number elements, matrix effect (physical matrix effects, such as fine versus course grain materials, may impact XRF performance) and interference effect (the spectral lines of elements may overlap distorting results for one or more elements). Especially, spectral interferences are very significant factors for accurate results. In this study, semi-quantitative analyzed manganese (II) oxide (MnO, 99.99%) was examined. Samples were pelleted and analyzed with XRF spectrometry (Bruker S8 Tiger). Unexpected peaks were obtained at the side of the major Mn peaks. Although sample does not contain Eu element, in results 0,3% Eu2O3 was observed. These result can occur high concentration of MnO and proximity of Mn and Eu lines. It can be eliminated by using correction equation or Mn concentration can confirm with other methods (such as Atomic absorption spectroscopy). Keywords: Spectral Interferences; Manganese (Mn); Europium (Eu); X-Ray Fluorescence Spectrometry Spectrum.

  20. X-ray fluorescence spectrometry analysis of mining related samples; Semiquantitative Roentgenfluoreszenzanalyse an bergbaurelevanten Proben

    Energy Technology Data Exchange (ETDEWEB)

    Leinert, P. [Lausitzer Analytik GmbH, Schwarze Pumpe (Germany)

    1997-09-01

    In many industries, especially in mining it is necessary to analyse occurring production process materials of unknown composition and of carious matrices in a short time. The determination of main components is very important, but also minor components and traces can be of interest for instance in pollution determination or the environmental investigation. The X-ray fluorescence spectrometry is a suitable method for fast analyse of a wide range of elements. This article gives a short and simplified description of the measuring principle and a overview about some international, German and ASTM-standards. It is described, how the standardless X-ray fluorescence analysis with the UniQuant system was used for a fast analysis of various mining related samples. The full english text is available from Lausitzer Analytik GmbH, An der Heide, 03139 Schwarze Pumpe/Germany. (orig.) [Deutsch] Anhand ausgewaehlter Beispiele aus dem Bergbaubereich konnte unter Verwendung von UniQuant die schnelle und preiswerte Analytik an Einzelproben verschiedenster Matrix demonstriert werden. Dabei wurden wegen der vielfach unbekannten etwaigen Zusammensetzung zunaechst nur die (vermuteten) Hauptkomponenten betrachtet. Die Ergebnisse belegen die Eignung der semiquantitativen Roentgenfluoreszenzanalyse zur Loesung der anstehenden Problemstellungen. Bei den genannten Vorteilen duerfen bestimmte Nachteile nicht unerwaehnt bleiben (ungenuegende Beruecksichtigung von Korngroessen- und Stoerelementeinfluessen, kurze Analysenzeit bedeutet kurzes Vermessen jeder einzelnen Elementlinie usw.). Oft koennen nur `Groessenordnungen` wiedergegeben werden, was besonders fuer nur in Spuren vorhandene Elemente zutrifft. (orig.)

  1. Development of a fast pixel array detector for use in microsecond time-resolved x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Barna, S.L.; Gruner, S.M.; Shepherd, J.A. [Princeton Univ., NJ (United States)] [and others

    1995-08-01

    A large-area pixel x-ray detector is being developed to collect eight successive frames of wide dynamic range two-dimensional images at 200kHz rates. Such a detector, in conjunction with a synchrotron radiation x-ray source, will enable time-resolved x-ray studies of proteins and other materials on time scales which have previously been inaccessible. The detector will consist of an array of fully-depleted 150 micron square diodes connected to a CMOS integrated electronics layer with solder bump-bonding. During each framing period, the current resulting from the x-rays stopped in the diodes is integrated in the electronics layer, and then stored in one of eight storage capacitors underneath the pixel. After the last frame, the capacitors are read out at standard data transmission rates. The detector has been designed for a well-depth of at least 10,000 x-rays (at 20keV), and a noise level of one x-ray. Ultimately, the authors intend to construct a detector with over one million pixels (1024 by 1024). They present the results of their development effort and various features of the design. The electronics design is discussed, with special attention to the performance requirements. The choice and design of the detective diodes, as they relate to x-ray stopping power and charge collection, are presented. An analysis of various methods of bump bonding is also presented. Finally, the authors discuss the possible need for a radiation-blocking layer, to be placed between the electronics and the detective layer, and various methods they have pursued in the construction of such a layer.

  2. A split-beam probe-pump-probe scheme for femtosecond time resolved protein X-ray crystallography

    Directory of Open Access Journals (Sweden)

    Jasper J. van Thor

    2015-01-01

    Full Text Available In order to exploit the femtosecond pulse duration of X-ray Free-Electron Lasers (XFEL operating in the hard X-ray regime for ultrafast time-resolved protein crystallography experiments, critical parameters that determine the crystallographic signal-to-noise (I/σI must be addressed. For single-crystal studies under low absorbed dose conditions, it has been shown that the intrinsic pulse intensity stability as well as mode structure and jitter of this structure, significantly affect the crystallographic signal-to-noise. Here, geometrical parameters are theoretically explored for a three-beam scheme: X-ray probe, optical pump, X-ray probe (or “probe-pump-probe” which will allow experimental determination of the photo-induced structure factor amplitude differences, ΔF, in a ratiometric manner, thereby internally referencing the intensity noise of the XFEL source. In addition to a non-collinear split-beam geometry which separates un-pumped and pumped diffraction patterns on an area detector, applying an additional convergence angle to both beams by focusing leads to integration over mosaic blocks in the case of well-ordered stationary protein crystals. Ray-tracing X-ray diffraction simulations are performed for an example using photoactive yellow protein crystals in order to explore the geometrical design parameters which would be needed. The specifications for an X-ray split and delay instrument that implements both an offset angle and focused beams are discussed, for implementation of a probe-pump-probe scheme at the European XFEL. We discuss possible extension of single crystal studies to serial femtosecond crystallography, particularly in view of the expected X-ray damage and ablation due to the first probe pulse.

  3. Medieval glass from the Cathedral in Paderborn: a comparative study using X-ray absorption spectroscopy, X-ray fluorescence, and inductively coupled laser ablation mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hormes, J. [University of Saskatchewan, Canadian Light Source Inc., Saskatoon, SK (Canada); Louisiana State University, CAMD, Baton Rouge, LA (United States); Roy, A.; Bovenkamp, G.L. [Louisiana State University, CAMD, Baton Rouge, LA (United States); Simon, K. [University of Goettingen, Geochemistry, Centre for Geosciences, Goettingen (Germany); Kim, C.Y. [University of Saskatchewan, Canadian Light Source Inc., Saskatoon, SK (Canada); Boerste, N. [Faculty for Theology Paderborn, Paderborn (Germany); Gai, S. [LWL - Archaeologie fuer Westfalen, Muenster (Germany)

    2013-04-15

    We have investigated four stained glass samples recovered from an archaeological excavation at the Cathedral in Paderborn (Germany) between 1978 and 1980. On two of the samples there are parts of paintings. Concentrations of major elements were determined using two independent techniques: LA-ICP-MS (a UV laser ablation microsampler combined with an inductively coupled plasma mass spectrometer) and synchrotron radiation X-ray excited X-ray fluorescence (SR-XRF). The SR-XRF data were quantified by using the program package PyMCA developed by the software group of the ESRF in Grenoble. Significant differences were found between the concentrations determined by the two techniques that can be explained by concentration gradients near the surface of the glasses caused, for example, by corrosion/leaching processes and the different surface sensitivities of the applied techniques. For several of the elements that were detected in the glass and in the colour pigments used for the paintings X-ray absorption near edge structure (XANES) spectra were recorded in order to determine the chemical speciation of the elements of interest. As was expected, most elements in the glass were found as oxides in their most stable form. Two notable exceptions were observed: titanium was not found as rutile - the most stable form of TiO{sub 2} - but in the form of anatase, and lead was not found in one defined chemical state but as a complex mixture of oxide, sulphate, and other compounds. (orig.)

  4. Multispecies Biofilms Transform Selenium Oxyanions into Elemental Selenium Particles: Studies Using Combined Synchrotron X-ray Fluorescence Imaging and Scanning Transmission X-ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Soo In; George, Graham N.; Lawrence, John R.; Kaminskyj, Susan G. W.; Dynes, James J.; Lai, Barry; Pickering, Ingrid J.

    2016-10-04

    Selenium (Se) is an element of growing environmental concern, because low aqueous concentrations can lead to biomagnification through the aquatic food web. Biofilms, naturally occurring microbial consortia, play numerous important roles in the environment, especially in biogeochemical cycling of toxic elements in aquatic systems. The complexity of naturally forming multispecies biofilms presents challenges for characterization because conventional microscopic techniques require chemical and physical modifications of the sample. Here, multispecies biofilms biotransforming selenium oxyanions were characterized using X-ray fluorescence imaging (XFI) and scanning transmission X-ray microscopy (STXM). These complementary synchrotron techniques required minimal sample preparation and were applied correlatively to the same biofilm areas. Sub-micrometer XFI showed distributions of Se and endogenous metals, while Se K-edge X-ray absorption spectroscopy indicated the presence of elemental Se (Se0). Nanoscale carbon K-edge STXM revealed the distributions of microbial cells, extracellular polymeric substances (EPS), and lipids using the protein, saccharide, and lipid signatures, respectively, together with highly localized Se0 using the Se LIII edge. Transmission electron microscopy showed the electron-dense particle diameter to be 50–700 nm, suggesting Se0 nanoparticles. The intimate association of Se0 particles with protein and polysaccharide biofilm components has implications for the bioavailability of selenium in the environment.

  5. Element distribution and iron speciation in mature wheat grains (Triticum aestivum L.) using synchrotron X-ray fluorescence microscopy mapping and X-ray absorption near-edge structure (XANES) imaging.

    Science.gov (United States)

    De Brier, Niels; Gomand, Sara V; Donner, Erica; Paterson, David; Smolders, Erik; Delcour, Jan A; Lombi, Enzo

    2016-08-01

    Several studies have suggested that the majority of iron (Fe) and zinc (Zn) in wheat grains are associated with phytate, but a nuanced approach to unravel important tissue-level variation in element speciation within the grain is lacking. Here, we present spatially resolved Fe-speciation data obtained directly from different grain tissues using the newly developed synchrotron-based technique of X-ray absorption near-edge spectroscopy imaging, coupling this with high-definition μ-X-ray fluorescence microscopy to map the co-localization of essential elements. In the aleurone, phosphorus (P) is co-localized with Fe and Zn, and X-ray absorption near-edge structure imaging confirmed that Fe is chelated by phytate in this tissue layer. In the crease tissues, Zn is also positively related to P distribution, albeit less so than in the aleurone. Speciation analysis suggests that Fe is bound to nicotianamine rather than phytate in the nucellar projection, and that more complex Fe structures may also be present. In the embryo, high Zn concentrations are present in the root and shoot primordium, co-occurring with sulfur and presumably bound to thiol groups. Overall, Fe is mainly concentrated in the scutellum and co-localized with P. This high resolution imaging and speciation analysis reveals the complexity of the physiological processes responsible for element accumulation and bioaccessibility.

  6. Diffraction enhanced imaging and x-ray fluorescence microtomography for analyzing biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, H.S.; Pereira, G.R.; Lopes, R.T. [Laboratorio de Instrumentacao Nuclear-COPPE/UFRJ-RJ (Brazil); Anjos, M.J. [Instituto de Fisica-UERJ-RJ (Brazil); Faria, P. [Instituto Nacional do Cancer-INCa-RJ (Brazil); Kellermann, G.; Perez, C.A. [Laboratorio Nacional de Luz Sincrotron-Campinas-SP (Brazil); Tirao, G. [Faculdad de Mat. Astronomia y Fisica (FAMAF), UNC. Cordoba (Argentina); Mazzaro, I. [Laboratorio de Optica de Raios X e Instrumentacao-UFPR-Curitiba-PR (Brazil); Giles, C. [Laboratorio de Cristalografia Aplicada e Raios X-UNICAMP-Campinas-SP (Brazil)

    2007-07-15

    In this work, breast tissue samples were investigated in order to verify the distribution of certain elements by x-ray fluorescence computed tomography (XRFCT) correlated with the characteristics and pathology of each tissue observed by diffraction enhanced imaging (DEI). The DEI system can show details in low attenuation tissues. It is based on the contrast imaging obtained by extinction, diffraction and refraction characteristics and can improve reduction in false positive and false negative diagnoses. XRFCT allows mapping of all elements within the sample, since even a minute fluorescence signal can be detected. DEI imaging techniques revealed the complex structure of the disease, confirmed by the histological section, and showed microstructures in all planes of the sample. The XRFCT showed the distribution of Zn, Cu and Fe at higher concentration. (authors)

  7. Promising X-ray fluorescent tests for superconducting tunnel junction detector

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, Stephan; Robinson, Art

    2001-01-11

    Scientists in the Physical Biosciences Division of the Ernest Orlando Berkeley National Laboratory (Berkeley Lab) studying transition metals in proteins with fluorescence-detected L-edge absorption spectroscopy have found the measurements to be extremely challenging. The difficulty is that the metal centers are present in very dilute concentrations so that their weak fluorescence is often obscured by strong background signals from carbon and oxygen. To solve this problem, the Berkeley group has been working with researchers from the Advanced Detector Group at the Lawrence Livermore National Laboratory on an energy-dispersive superconducting tunnel junction x-ray detector. These devices in principle have the energy resolution needed to reveal the metal signal. The most recent results with the latest version of the detector on Beamline 4.0.1-2 at the Advanced Light Source (ALS) illustrate the promise of the cryogenic detector strategy not only for this application but also for spectroscopy of other types of dilute samples.

  8. Analysis of stainless steel samples by energy dispersive X-ray fluorescence (EDXRF) spectrometry

    Indian Academy of Sciences (India)

    M K Tiwari; A K Singh; K J S Sawhney

    2001-12-01

    A simple method for the analysis of stainless steel samples is presented which is based on radioisotope excited energy dispersive X-ray fluorescence (EDXRF) spectrometry and does not require any type-standards. Both absorption and enhancement effects have been taken into account in the fundamental parameter method for quantitative analysis and an iterative approach is followed for calculation of concentrations in steel samples. Non-linear least square fitting (NL-LSF) procedures have been used to determine accurately the fluorescent peak intensities. The method has been tested by analysing several CRM standard reference samples and 304 and 316 steel samples assuming as unknown. The EDXRF results have also been compared with the results of analysis of same samples by vacuum emission spark spectrometry (VES). Obtained values for concentration in steel samples match quite well with their certified values.

  9. Fabrication and testing of a newly designed slit system for depth-resolved X-ray diffraction measurements.

    Science.gov (United States)

    Sinsheimer, John; Bouet, Nathalie; Ghose, Sanjit; Dooryhee, Eric; Conley, Ray

    2016-11-01

    A new system of slits called `spiderweb slits' have been developed for depth-resolved powder or polycrystalline X-ray diffraction measurements. The slits act on diffracted X-rays to select a particular gauge volume of sample, while absorbing diffracted X-rays from outside of this volume. Although the slit geometry is to some extent similar to that of previously developed conical slits or spiral slits, this new design has advantages over the previous ones in use for complex heterogeneous materials and in situ and operando diffraction measurements. For example, the slits can measure a majority of any diffraction cone for any polycrystalline material, over a continuous range of diffraction angles, and work for X-ray energies of tens to hundreds of kiloelectronvolts. The design is generated and optimized using ray-tracing simulations, and fabricated through laser micromachining. The first prototype was successfully tested at the X17A beamline at the National Synchrotron Light Source, and shows similar performance to simulations, demonstrating gauge volume selection for standard powders, for all diffraction peaks over angles of 2-10°. A similar, but improved, design will be implemented at the X-ray Powder Diffraction beamline at the National Synchrotron Light Source II.

  10. Scanning Transmission X-ray Microscopy with X-ray Fluorescence Detection at the XUV Beamline P04, PETRA III, DESY

    Science.gov (United States)

    Andrianov, K.; Lühl, L.; Nisius, T.; Haidl, A.; Gnewkow, R.; Lötgering, L.; Dierks, H.; Kanngießer, B.; Wilhein, T.

    2017-06-01

    The presented scanning transmission x-ray microscope (STXM), build on top of our existing modular platform (FlexIX) for high resolution imaging experiments, allows versatile investigations of different samples. The FlexIX endstation allows to switch between a Full Field and a STXM mode. For the STXM mode we use a spatialy resolved detector together with an energy dispersive detector, this allows to investigate the morphology and the chemical or elemental distribution of the sample simultaneous. The combination of the nanoscopy endstation and the XUV beamline P04 results in a powerful tool for investigations of life science samples.

  11. Comparison of the data of X-ray microtomography and fluorescence analysis in the study of bone-tissue structure

    Science.gov (United States)

    Asadchikov, V. E.; Senin, R. A.; Blagov, A. E.; Buzmakov, A. V.; Gulimova, V. I.; Zolotov, D. A.; Orekhov, A. S.; Osadchaya, A. S.; Podurets, K. M.; Savel'ev, S. V.; Seregin, A. Yu.; Tereshchenko, E. Yu.; Chukalina, M. V.; Kovalchuk, M. V.

    2012-09-01

    The possibility of localizing clusters of heavy atoms is substantiated by comparing the data of X-ray microtomography at different wavelengths, scanning electron microscopy, and X-ray fluorescence analysis. The proximal tail vertebrae of Turner's thick-toed gecko ( Chondrodactylus turneri) have been investigated for the first time by both histological and physical methods, including X-ray microtomography at different wavelengths and elemental analysis. This complex methodology of study made it possible to reveal the regions of accumulation of heavy elements in the aforementioned bones of Turner's thick-toed gecko.

  12. Non-conventional applications of a noninvasive portable X-ray diffraction/fluorescence instrument

    Science.gov (United States)

    Chiari, Giacomo; Sarrazin, Philippe; Heginbotham, Arlen

    2016-11-01

    Noninvasive techniques have become widespread in the cultural heritage analytical domain. The popular handheld X-ray fluorescence (XRF) devices give the elemental composition of all the layers that X-rays can penetrate, but no information on how atoms are bound together or at which depth they are located. A noninvasive portable X-ray powder diffraction/X-ray fluorescence (XRD/XRF) device may offer a solution to these limitations, since it can provide information on the composition of crystalline materials. This paper introduces applications of XRD beyond simple phase recognition. The two fundamental principles for XRD are: (1) the crystallites should be randomly oriented, to ensure proper intensity to all the diffraction peaks, and (2) the material should be positioned exactly in the focal plane of the instrument, respecting its geometry, as any displacement of the sample would results in 2 θ shifts of the diffraction peaks. In conventional XRD, the sample is ground and set on the properly positioned sample holder. Using a noninvasive portable instrument, these two requirements are seldom fulfilled. The position, size and orientation of a given crystallite within a layered structure depend on the object itself. Equation correlating the displacement (distance from the focal plane) versus peak shift (angular difference in 2 θ from the standard value) is derived and used to determine the depth at which a given substance is located. The quantitative composition of two binary Cu/Zn alloys, simultaneously present, was determined measuring the cell volume and using Vegard's law. The analysis of the whole object gives information on the texture and possible preferred orientations of the crystallites, which influences the peak intensity. This allows for the distinction between clad and electroplated daguerreotypes in the case of silver and between ancient and modern gilding for gold. Analyses of cross sections can be carried out successfully. Finally, beeswax, used in

  13. Non-conventional applications of a noninvasive portable X-ray diffraction/fluorescence instrument

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, Giacomo [Getty Conservation Institute, Science Department, Los Angeles, CA (United States); Sarrazin, Philippe [Examinart LLC, Sunnyvale, CA (United States); Heginbotham, Arlen [The J. Paul Getty Museum, Sculpture and Decorative Arts Conservation, Los Angeles, CA (United States)

    2016-11-15

    Noninvasive techniques have become widespread in the cultural heritage analytical domain. The popular handheld X-ray fluorescence (XRF) devices give the elemental composition of all the layers that X-rays can penetrate, but no information on how atoms are bound together or at which depth they are located. A noninvasive portable X-ray powder diffraction/X-ray fluorescence (XRD/XRF) device may offer a solution to these limitations, since it can provide information on the composition of crystalline materials. This paper introduces applications of XRD beyond simple phase recognition. The two fundamental principles for XRD are: (1) the crystallites should be randomly oriented, to ensure proper intensity to all the diffraction peaks, and (2) the material should be positioned exactly in the focal plane of the instrument, respecting its geometry, as any displacement of the sample would results in 2θ shifts of the diffraction peaks. In conventional XRD, the sample is ground and set on the properly positioned sample holder. Using a noninvasive portable instrument, these two requirements are seldom fulfilled. The position, size and orientation of a given crystallite within a layered structure depend on the object itself. Equation correlating the displacement (distance from the focal plane) versus peak shift (angular difference in 2θ from the standard value) is derived and used to determine the depth at which a given substance is located. The quantitative composition of two binary Cu/Zn alloys, simultaneously present, was determined measuring the cell volume and using Vegard's law. The analysis of the whole object gives information on the texture and possible preferred orientations of the crystallites, which influences the peak intensity. This allows for the distinction between clad and electroplated daguerreotypes in the case of silver and between ancient and modern gilding for gold. Analyses of cross sections can be carried out successfully. Finally, beeswax, used in

  14. Synchrotron X-Ray Fluorescence Microscopy of Gallium in Bladder Tissue following Gallium Maltolate Administration during Urinary Tract Infection

    OpenAIRE

    Ball, Katherine R.; Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L.; Blyth, Robert I. R.; Sham, Tsun-Kong; Dowling, Patricia M.; Thompson, Julie

    2013-01-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived ...

  15. Investigation on new scintillators for subnanosecond time-resolved x-ray measurements

    Science.gov (United States)

    Haruki, R.; Shibuya, K.; Nishikido, F.; Koshimizu, M.; Yoda, Y.; Kishimoto, S.

    2010-03-01

    We investigated new x-ray detectors for nuclear resonant scattering measurements with high energy x rays. The organic-inorganic perovskite scintillator of phenethylamine lead halide ((C6H5C2H4NH3)2PbX4) (X:Br, I) was used. These compounds have fast light emission due to an exciton. They include heavy atoms, which make the detector to have high efficiency to high energy x rays. The merit of these scintillators is that we can make a thick crystal compared to a Si wafer which is used in an avalanche photo-diode detector. We successfully measured 67.41 keV x ray signals, the energy of 61Ni nuclear resonant scattering, with high detection efficiency of 42.5 % by the scintillator.

  16. Determination of $L_{3}$ subshell X-ray production cross-sections and fluorescence yields of Pb, Th and U

    CERN Document Server

    Simsek, O

    2000-01-01

    A study of L/sub 3/ subshell X-ray production cross-sections and fluorescence yields by using characteristic K X-rays as the exciting radiation is described. Only the L/sub 3/ subshells of Pb, Th and U were excited by the characteristic K X-rays of the elements used as secondary sources. The cross-sections for the production of L/sub l/, L/sub alpha / and L/sub beta / groups of L/sub 3/ subshell X-rays of Pb, Th and U have been measured using photoionization by Rb, Nb and Mo K X-rays. The measured L/sub 3/ X-ray production cross-section values for Pb, Th and U are in good agreement with the theoretical ones evaluated using L/sub 3/ subshell fluorescence yield omega /sub 3/, fractions of the radiative width F/sub 3i/ and L/sub 3/ subshell photoionization cross-section sigma /sub 3/. The L/sub 3/ subshell fluorescence yields ( omega /sub 3/) have also been computed using the presently measured cross-section values and the theoretical L/sub 3/ subshell photoionization cross-section values. These results are comp...

  17. Contribution of inner shell Compton ionization to the X-ray fluorescence line intensity

    Science.gov (United States)

    Fernández, Jorge E.; Scot, Viviana; Di Giulio, Eugenio

    2016-10-01

    The Compton effect is a potential ionization mechanism of atoms. It produces vacancies in inner shells that are filled with the same mechanism of atomic relaxation as the one following photo-absorption. This contribution to X-ray fluorescence emission is frequently neglected because the total Compton cross-section is apparently much lower than the photoelectric one at useful X-ray energies. However, a more careful analysis suggests that is necessary to consider single shell cross sections (instead of total cross sections) as a function of energy. In this article these Compton cross sections are computed for the shells K, L1-L3 and M1-M5 in the framework of the impulse approximation. By comparing the Compton and the photoelectric cross-section for each shell it is then possible to determine the extent of the Compton correction to the intensity of the corresponding characteristic lines. It is shown that for the K shell the correction becomes relevant for excitation energies which are too high to be influent in X-ray spectrometry. In contrast, for L and M shells the Compton contribution is relevant for medium-Z elements and medium energies. To illustrate the different grades of relevance of the correction, for each ionized shell, the energies for which the Compton contribution reaches the extent levels of 1, 5, 10, 20, 50 and 100% of the photoelectric one are determined for all the elements with Z = 11-92. For practical applications it is provided a simple formula and fitting coefficients to compute average correction levels for the shells considered.

  18. Simulated 'On-Line' Wear Metal Analysis of Lubricating Oils by X-Ray Fluorescence Spectroscopy

    Science.gov (United States)

    Kelliher, Warren C.; Partos, Richard D.; Nelson, Irina

    1996-01-01

    The objective of this project was to assess the sensitivity of X-ray Fluorescence Spectroscopy (XFS) for quantitative evaluation of metal particle content in engine oil suspensions and the feasibility of real-time, dynamic wear metal analysis. The study was focused on iron as the majority wear metal component. Variable parameters were: particle size, particle concentration and oil velocity. A commercial XFS spectrometer equipped with interchangeable static/dynamic (flow cell) sample chambers was used. XFS spectra were recorded for solutions of Fe-organometallic standard and for a series of DTE oil suspensions of high purity spherical iron particles of 2g, 4g, and 8g diameter, at concentrations from 5 ppm to 5,000 ppm. Real contaminated oil samples from Langley Air Force Base aircraft engines and NASA Langley Research Center wind tunnels were also analyzed. The experimental data conform the reliability of XFS as the analytical method of choice for this project. Intrinsic inadequacies of the instrument for precise analytic work at low metal concentrations were identified as being related to the particular x-ray beam definition, system geometry, and flow-cell materials selection. This work supports a proposal for the design, construction and testing of a conceptually new, miniature XFS spectrometer with superior performance, dedicated to on-line, real-time monitoring of lubricating oils in operating engines. Innovative design solutions include focalization of the incident x-ray beam, non-metal sample chamber, and miniaturization of the overall assembly. The instrument would contribute to prevention of catastrophic engine failures. A proposal for two-year funding has been presented to NASA Langley Research Center Internal Operation Group (IOG) Management, to continue the effort begun by this summer's project.

  19. Resonant inelastic scattering in dilute magnetic semiconductors by x-ray fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lawniczak-Jablonska, K. [Lawrence Berkeley National Lab., CA (United States)]|[Institute of Physics, Warsaw (Poland); Jia, J.J.; Underwood, J.H. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    As modern, technologically important materials have become more complex, element specific techniques have become invaluable in studying the electronic structure of individual components from the system. Soft x-ray fluorescence (SXF) and absorption (SXA) spectroscopies provide a unique means of measuring element and angular momentum density of electron states, respectively, for the valence and conducting bands in complex materials. X-ray absorption and the decay through x-ray emission are generally assumed to be two independent one-photon processes. Recent studies, however have demonstrated that SXF excited near the absorption threshold generate an array of spectral features that depend on nature of materials, particularly on the localization of excited states in s and d-band solids and that these two processes can no be longer treated as independent. Resonant SXF offers thus the new way to study the dynamics of the distribution of electronic valence states in the presence of a hole which is bound to the electron low lying in the conduction band. This process can simulate the interaction between hole-electron pair in wide gap semiconductors. Therefore such studies can help in understanding of transport and optics phenomena in the wide gap semiconductors. The authors report the result of Mn and S L-resonant emission in Zn{sub 1{minus}x}Mn{sub x}S (with x=0.2 and 0.3) and MnS as the energy of exciting radiation is tuned across the Mn and S L{sub 3,2} absorption edge, along with the resonant excited spectra from elemental Mn as a reference.

  20. Quantification of metals in lipstick by energy dispersive X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Wouk, Luana Cristina; Melquiades, Fabio Luiz [Universidade Estadual do Centro Oeste (UNICENTRO), PR (Brazil). Dept. de Fisica

    2011-07-01

    Full text: The objective of this work is to analyze lipstick and lip balm by Energy Dispersive X-Ray Fluorescence and verify if the concentration of the found elements are in accordance with federal rules. Two lip balm and 30 lipstick commercially available were analyzed without preparation. The samples were rubbed on a mylar film until they form a relatively homogeneous layer over entire surface of the film. The superficial density of the samples ranged from 0,0004 to 0,015 g cm{sup -2} , which characterize thin film geometry. Sensitivity values were determined using MicroMatter standards. The measurement system, from Applied Nuclear Physics Laboratory of UEL, consists in a Si-PIN X-ray detector (221 eV resolution for 5,9 keV line, 25 {mu}m Be window) and a mini X-ray tube (4W, Ag target, 50 {mu}m Ag filter). One of the lip balm presented 2620 {+-} 477 {mu}g g{sup -1} of Ti and in the other sample none inorganic elements, which characterize a formulation based on organic compounds. In the lipstick were found the following elements and the number of samples in which it appears, with its respective range of concentration in {mu}g g{sup -1}: Ti (17) 691 to 12721, Fe (22) 237 to 16377, Zn (3) 105 to 2850, Br (2) 510 to 3097, Sr(4) 254 to 1170, Ba (2) 58170 to 90506 and Bi (1) 16275 {+-} 798. According to Brazilian federal rules (ANVISA 79.094) it is not permitted the presence of As and Pb in the formulations. The methodology demonstrated to be suitable for quantification of metals at in natura samples of lipsticks, discarding sample preparation. In sequence a detailed study of the influence of these elements on human health will be performed. (author)

  1. Risk and benefit of diffraction in Energy Dispersive X-ray fluorescence mapping

    Science.gov (United States)

    Nikonow, Wilhelm; Rammlmair, Dieter

    2016-11-01

    Energy dispersive X-ray fluorescence mapping (μ-EDXRF) is a fast and non-destructive method for chemical quantification and therefore used in many scientific fields. The combination of spatial and chemical information is highly valuable for understanding geological processes. Problems occur with crystalline samples due to diffraction, which appears according to Bragg's law, depending on the energy of the X-ray beam, the incident angle and the crystal parameters. In the spectra these peaks can overlap with element peaks suggesting higher element concentrations. The aim of this study is to investigate the effect of diffraction, the possibility of diffraction removal and potential geoscientific applications for X-ray mapping. In this work the μ-EDXRF M4 Tornado from Bruker was operated with a Rh-tube and polychromatic beam with two SDD detectors mounted each at ± 90° to the tube. Due to the polychromatic beam the Bragg condition fits for several mineral lattice planes. Since diffraction depends on the angle, it is shown that a novel correction approach can be applied by measuring from two different angles and calculating the minimum spectrum of both detectors gaining a better limit of quantification for this method. Furthermore, it is possible to use the diffraction information for separation of differently oriented crystallites within a monomineralic aggregate and obtain parameters like particle size distribution for the sample, as it is done by thin section image analysis in cross-polarized light. Only with μ-EDXRF this can be made on larger samples without preparation of thin sections.

  2. In situ spatial and time-resolved studies of electrochemical reactions by scanning transmission X-ray microscopy.

    Science.gov (United States)

    Guay, Daniel; Stewart-Ornstein, Jacob; Zhang, Xuerong; Hitchcock, Adam P

    2005-06-01

    The first in situ measurements with scanning transmission X-ray microscopy (STXM) of an active electrochemical cell are reported. An electrochemical wet cell, consisting of an electrodeposited polyaniline thin film on a thin Au film covered by an overlayer of 1 M HCl solution sitting between two X-ray transparent silicon nitride windows, was assembled. X-ray absorption images and spatial and time-resolved spectra of this system under potential control were examined using the beamline 5.3.2 STXM at the Advanced Light Source. The chemical state of the polyaniline film was reversibly converted between reduced (leucoemeraldine) and oxidized (emeraldine chloride) states by changing the applied potential. The electrochemical changes were monitored by spatially resolved C 1s and N 1s X-ray absorption spectroscopy and chemical-state selective imaging. Comparison of differences between images at two energies at different potentials provided electrochemical contrast with a resolution better than 50 nm, thereby monitoring that component of the polyaniline film that was electrochemically active. Kinematic studies in the subsecond regime are demonstrated.

  3. Time-Lapse Observation of Electrolysis of Copper Sulfate with a Full-Field X-ray Fluorescence Imaging Microscope

    Science.gov (United States)

    Ohigashi, Takuji; Aota, Tatsuya; Watanabe, Norio; Takano, Hidekazu; Yokosuka, Hiroki; Aoki, Sadao

    2008-06-01

    The time-lapse observation of the electrodeposition of copper in copper sulfate solution was performed by imaging X-ray fluorescence from the copper deposition. The X-ray fluorescence was directly imaged with a full-field Wolter mirror microscope, which was constructed at the Photon Factory. Controlling the electric current in the solution from 0 to 71.7 µA, the deposition of copper on a Pt cathode was directly observed by imaging its X-ray fluorescence. One exposure time for obtaining an X-ray fluorescence image was 80 s. Then, it was 17 min later from the beginning of the electrolysis when the X-ray fluorescence image of the electrodeposition is observed for the first time. At this exposure time, the detection limit of the mass of copper was estimated to be 0.60 pg/image, which was calculated using test samples of 1.00×10-3-1.00 mol/l copper sulfate solutions.

  4. A deep view in cultural heritage - confocal micro X-ray spectroscopy for depth resolved elemental analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kanngiesser, B.; Malzer, W.; Mantouvalou, I. [Technical University of Berlin, Institut fuer Optik und Atomare Physik, Berlin (Germany); Sokaras, D. [NCSR ' Demokritos' , Institute of Nuclear Physics, Athens (Greece); SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA (United States); Karydas, A.G. [NCSR ' Demokritos' , Institute of Nuclear Physics, Athens (Greece); International Atomic Energy Agency, Nuclear Spectrometry and Applications Laboratory (NSAL), Seibersdorf (Austria)

    2012-02-15

    Quantitative X-ray fluorescence (XRF) and particle induced X-ray emission (PIXE) techniques have been developed mostly for the elemental analysis of homogeneous bulk or very simple layered materials. Further on, the microprobe version of both techniques is applied for 2D elemental mapping of surface heterogeneities. At typical XRF/PIXE fixed geometries and exciting energies (15-25 keV and 2-3 MeV, respectively), the analytical signal (characteristic X-ray radiation) emanates from a variable but rather extended depth within the analyzed material, according to the exciting probe energy, set-up geometry, specimen matrix composition and analyte. Consequently, the in-depth resolution offered by XRF and PIXE techniques is rather limited for the characterization of materials with micrometer-scale stratigraphy or 3D heterogeneous structures. This difficulty has been over-passed to some extent in the case of an X-ray or charged particle microprobe by creating the so-called confocal geometry. The field of view of the X-ray spectrometer is spatially restricted by a polycapillary X-ray lens within a sensitive microvolume formed by the two inter-sectioned focal regions. The precise scanning of the analyzed specimen through the confocal microvolume results in depth-sensitive measurements, whereas the additional 2D scanning microprobe possibilities render to element-specific 3D spatial resolution (3D micro-XRF and 3D micro-PIXE). These developments have contributed since 2003 to a variety of fields of applications in environmental, material and life sciences. In contrast to other elemental imaging methods, no size restriction of the objects investigated and the non-destructive character of analysis have been found indispensable for cultural heritage (CH) related applications. The review presents a summary of the experimental set-up developments at synchrotron radiation beamlines, particle accelerators and desktop spectrometers that have driven methodological developments and

  5. Spectrum reconstruction method based on the detector response model calibrated by x-ray fluorescence

    Science.gov (United States)

    Li, Ruizhe; Li, Liang; Chen, Zhiqiang

    2017-02-01

    Accurate estimation of distortion-free spectra is important but difficult in various applications, especially for spectral computed tomography. Two key problems must be solved to reconstruct the incident spectrum. One is the acquisition of the detector energy response. It can be calculated by Monte Carlo simulation, which requires detailed modeling of the detector system and a high computational power. It can also be acquired by establishing a parametric response model and be calibrated using monochromatic x-ray sources, such as synchrotron sources or radioactive isotopes. However, these monochromatic sources are difficult to obtain. Inspired by x-ray fluorescence (XRF) spectrum modeling, we propose a feasible method to obtain the detector energy response based on an optimized parametric model for CdZnTe or CdTe detectors. The other key problem is the reconstruction of the incident spectrum with the detector response. Directly obtaining an accurate solution from noisy data is difficult because the reconstruction problem is severely ill-posed. Different from the existing spectrum stripping method, a maximum likelihood-expectation maximization iterative algorithm is developed based on the Poisson noise model of the system. Simulation and experiment results show that our method is effective for spectrum reconstruction and markedly increases the accuracy of XRF spectra compared with the spectrum stripping method. The applicability of the proposed method is discussed, and promising results are presented.

  6. Tibial lead determination by 99Tcm radiopharmaceutical x-ray fluorescence.

    Science.gov (United States)

    Mountford, P J; Green, S; Bradley, D A; Lewis, A D; Morgan, W D

    1994-04-01

    The feasibility of measuring tibial lead concentration by x-ray fluorescence with an internal 99Tcm labelled bone-seeking radiopharmaceutical was investigated using phantoms containing known values of lead concentration and 99Tcm activity. The minimum detectable concentration (MDC) at two standard deviations based on the counts in the Kalpha1 peak of 10.9 microg Pb ml(-1) was estimated to correspond to an MDC for an individual within a range of approximately 8-15 microg Pb (g bone mineral)(-1) if the counts from all four K x-ray peaks were included. Due to its much greater dose compared to an external source, the MDC of this internal source technique would have to be reduced before it could be used for measurements of occupationally or environmentally exposed individuals other than as an adjunct for a patient undergoing a bone scan. Methods of achieving such a reduction include increasing the acquisition time and the number of HPGE detectors, and optimizing the design of their collimators.

  7. Fundamental parameter based quantification algorithm for confocal nano-X-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schoonjans, Tom, E-mail: Tom.Schoonjans@UGent.be [X-ray Microspectroscopy and Imaging Research Group (XMI), Department of Analytical Chemistry, Ghent University, Krijgslaan 281 S12, B-9000 Ghent (Belgium); Silversmit, Geert; Vekemans, Bart [X-ray Microspectroscopy and Imaging Research Group (XMI), Department of Analytical Chemistry, Ghent University, Krijgslaan 281 S12, B-9000 Ghent (Belgium); Schmitz, Sylvia [Geosciences Institute/Mineralogy, Goethe University Frankfurt, Altenhoeferallee 1, D-60438 Frankfurt (Germany); Burghammer, Manfred; Riekel, Christian [ESRF, 6 rue Jules Horowitz, BP220, F-38043 Grenoble Cedex (France); Brenker, Frank E. [Geosciences Institute/Mineralogy, Goethe University Frankfurt, Altenhoeferallee 1, D-60438 Frankfurt (Germany); Vincze, Laszlo, E-mail: Laszlo.Vincze@UGent.be [X-ray Microspectroscopy and Imaging Research Group (XMI), Department of Analytical Chemistry, Ghent University, Krijgslaan 281 S12, B-9000 Ghent (Belgium)

    2012-01-15

    A new method for the quantification of X-ray fluorescence (XRF) was derived based on the fundamental parameter method (FPM). The FPM equations were adapted to accommodate the special case of confocal nano-XRF, i.e. X-ray nano-beam excitation coupled with confocal detection, taking into account the special characteristics of the detector channel polycapillary. A thorough error estimation algorithm based on the Monte Carlo method was applied, producing a detailed analysis of the uncertainties of the quantification results. The new FPM algorithm was applied on confocal nano-XRF data obtained from cometary dust returned by NASA's Stardust mission, recorded at beamline ID13 of the European Synchrotron Radiation Facility. - Highlights: Black-Right-Pointing-Pointer A new method for the quantification of confocal XRF is presented. Black-Right-Pointing-Pointer The quantification is based on the fundamental parameter method (FPM). Black-Right-Pointing-Pointer The new FPM algorithm was applied for the analysis of unique cometary dust particles. Black-Right-Pointing-Pointer The cometary particles were returned by NASA's Stardust mission in 2006. Black-Right-Pointing-Pointer Error estimation is based on the Monte Carlo method.

  8. [Determination of 22 Elements in Herb Tea by X-Ray Fluorescence Spectrometry].

    Science.gov (United States)

    Li, Dan; Ge, Liang-quan; Wang, Guang-xi; Lai, Wan-chang; Zhai, Juan; Chen, Lu

    2015-07-01

    N, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba and Pb in herb tea were determined by X-ray fluorescence spectrometry with pressed powder pellets. The measuring conditions of target elements were investigated, including how to select its analytical line. In addition to Ba and Pb using L line, Kalpha line was selected for the rest. When the Compton scattered radiation of Rh Kalpha was measured, The X-ray tube voltage should be appropriately reduced, and the appropriate tube current should be selected. The matrix effect was corrected by empirical coefficient method and using scattered radiation (the Rayleigh scattered radiation of Rh Lalpha, the scattered background of 0.1876 nm wavelength position and the Compton scattered radiation of Rh Kalpha) as internal standard, and the spectral overlapping interference of some elements (N, Na, Ca, Ti, Mn, Sr and Ba) was corrected. For the target elements, the detection limit of this method was low, and its accuracy and precision were high. The results showed that there were abandon of elements in herb tea, of which different kinds had different components, even the same kind of herb tea with different source had some difference in element and content more or less, however, there was a lot of similarity between the features of its components. In a word, this method could achieve multi-element determination of herb tea, and it was simple in operation, low cost, rapid, and accurate.

  9. Toward chromium speciation in solids using wavelength dispersive X-ray fluorescence spectrometry Cr Kβ lines.

    Science.gov (United States)

    Malherbe, J; Claverie, F

    2013-04-22

    The determination of chromium speciation in solid samples is critical for environmental and industrial purposes. Several analytical methods exist to perform such a determination either directly in solid state or liquid state after an extraction step, each of them having some limitations. In this study, the use of a high-resolution wavelength-dispersive X-ray fluorescence spectrometer to determine and quantify chromium species is investigated by looking at the differences in the Kβ transition profiles between Cr(0), Cr(III) and Cr(VI) compounds. Three different approaches were tested and compared to determine the Cr(VI) fraction of known mixtures: relative height and peak fitting using calibration mixtures, partial least square regression (PLS) of pure compounds, and principal component regression (PCR) of pure compounds. The accuracy of these methods was found to be about the same with an average relative error in the range of 15%. However, PLS and PCR can be easily implemented in an automated way contrary to peak fitting which can be sometimes perceived as analyst-dependant. Another advantage of using PLS and PCR is that information concerning the other oxidation states present in the sample can be retrieved. Finally, PLS and the peak height approach can be used up to 0.5% total chromium which make the XRF an alternative technique to X-ray induced photoelectron spectroscopy (XPS) for chromium speciation in solid state.

  10. Radiography and X-ray fluorescence used to analyze cultural and artistic artifacts

    Energy Technology Data Exchange (ETDEWEB)

    Rizzutto, Marcia A.; Kajiya, Elizabeth M.; Campos, Pedro H.O.V. de; Almeida, Paula A.D., E-mail: rizzutto@if.usp.br, E-mail: elizabethkajiya@gmail.com [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2013-07-01

    Since 2003 the analyses of artistic and cultural heritage objects at LAMFI-USP (Laboratorio de Analises de Materiais com Feixes Ionicos), initially restricted to ion beam methods, are growing steadily. Since then, alternative methodologies and procedures have been incorporated to better characterize these objects, which possess distinct physical characteristics and also high cultural and monetary value. The examinations in this kind of objects were expanded to other non-destructive analytical techniques like portable EDXRF (Energy Dispersive X-ray Fluorescence) analysis, X-ray radiography, visible photography, UV (ultraviolet) and IR (infrared) light imaging that are helping to better understand these art objects, particularly paintings. These techniques are helping the analyses of the conservation state of the objects and also revealing characteristics of the painter such as underlying drawings, which help understand the creative process of the artist. These new procedures of analysis are aimed to enable better analytic research in archaeology and artistic and cultural heritage objects and to provide results that subsidize authentic investigations of art objects as well as the origin of archaeological artifacts, while stimulating archeometry and 'arteometry' research in Brazilian Museums. (author)

  11. 3D Imaging of Transition Metals in the Zebrafish Embryo by X-ray Fluorescence Microtomography

    Science.gov (United States)

    Bourassa, Daisy; Gleber, Sophie-Charlotte; Vogt, Stefan; Yi, Hong; Will, Fabian; Richter, Heiko; Shin, Chong Hyun; Fahrni, Christoph J.

    2014-01-01

    Synchrotron X-ray fluorescence (SXRF) microtomography has emerged as a powerful technique for the 3D visualization of the elemental distribution in biological samples. The mechanical stability, both of the instrument and the specimen, is paramount when acquiring tomographic projection series. By combining the progressive lowering of temperature method (PLT) with femtosecond laser sectioning, we were able to embed, excise, and preserve a zebrafish embryo at 24 hours post fertilization in an X-ray compatible, transparent resin for tomographic elemental imaging. Based on a data set comprised of 60 projections, acquired with a step size of 2 μm during 100 hours of beam time, we reconstructed the 3D distribution of zinc, iron, and copper using the iterative maximum likelihood expectation maximization (MLEM) reconstruction algorithm. The volumetric elemental maps, which entail over 124 million individual voxels for each transition metal, revealed distinct elemental distributions that could be correlated with characteristic anatomical features at this stage of embryonic development. PMID:24992831

  12. Modeling of x-ray fluorescence using MCNPX and Geant4

    Energy Technology Data Exchange (ETDEWEB)

    Rajasingam, Akshayan [Los Alamos National Laboratory; Hoover, Andrew S [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory

    2009-01-01

    X-Ray Fluorescence (XRF) is one of thirteen non-destructive assay techniques being researched for the purpose of quantifying the Pu mass in used fuel assemblies. The modeling portion of this research will be conducted with the MCNPX transport code. The research presented here was undertaken to test the capability of MCNPX so that it can be used to benchmark measurements made at the ORNL and to give confidence in the application of MCNPX as a predictive tool of the expected capability of XRF in the context of used fuel assemblies. The main focus of this paper is a code-to-code comparison between MCNPX and Geant4 code. Since XRF in used fuel is driven by photon emission and beta decay of fission fragments, both terms were independently researched. Simple cases and used fuel cases were modeled for both source terms. In order to prepare for benchmarking to experiments, it was necessary to determine the relative significance of the various fission fragments for producing X-rays.

  13. Synchrotron-based X-ray fluorescence imaging and elemental mapping from biological samples

    Energy Technology Data Exchange (ETDEWEB)

    D Rao; M Swapna; R Cesareo; A Brunetti; T Akatsuka; T Yuasa; T Takeda; G Gigante

    2011-12-31

    The present study utilized the new hard X-ray microspectroscopy beamline facility, X27A, available at NSLS, BNL, USA, for elemental mapping. This facility provided the primary beam in a small spot of the order of {approx}10 {mu}m, for focussing. With this spatial resolution and high flux throughput, the synchrotron-based X-ray fluorescent intensities for Mn, Fe, Zn, Cr, Ti and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector. The sample is scanned in a 'step-and-repeat' mode for fast elemental mapping measurements and generated elemental maps at 8, 10 and 12 keV, from a small animal shell (snail). The accumulated trace elements, from these biological samples, in small areas have been identified. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other elements.

  14. Detection of Fingerprints Based on Elemental Composition Using Micro-X-Ray Fluorescence.

    Energy Technology Data Exchange (ETDEWEB)

    Worley, C. G. (Christopher G.); Wiltshire, S. (Sara); Miller, T. C. (Thomasin C.); Havrilla, G. J. (George J.); Majidi, V. (Vahid)

    2005-01-01

    A method was developed to detect fingerprints using a technique known as micro-X-ray fluorescence. The traditional method of detecting fingerprints involves treating the sample with certain powders, liquids, or vapors to add color to the fingerprint so that it can be easily seen and photographed for forensic purposes. This is known as contrast enhancement, and a multitude of chemical processing methods have been developed in the past century to render fingerprints visible. However, fingerprints present on certain substances such as fibrous papers and textiles, wood, leather, plastic, adhesives, and human skin can sometimes be difficult to detect by contrast enhancement. Children's fingerprints are also difficult to detect due to the absence of sebum on their skin, and detection of prints left on certain colored backgrounds can sometimes be problematic. Micro-X-ray fluorescence (MXRF) was studied here as a method to detect fingerprints based on chemical elements present in fingerprint residue. For example, salts such as sodium chloride and potassium chloride excreted in sweat are sometimes present in detectable quantities in fingerprints. We demonstrated that MXRF can be used to detect this sodium, potassium, and chlorine from such salts. Furthermore, using MXRF, each of these elements (and many other elements if present) can be detected as a function of location on a surface, so we were able to 'see' a fingerprint because these salts are deposited mainly along the patterns present in a fingerprint (traditionally called friction ridges in forensic science). MXRF is not a panacea for detecting all fingerprints; some prints will not contain enough detectable material to be 'seen'; however, determining an effective means of coloring a fingerprint with traditional contrast enhancement methods can sometimes be an arduous process with limited success. Thus, MXRF offers a possible alternative for detecting fingerprints, and it does not require any

  15. The use of time-resolved X-ray diffraction and sample techniques for studying the muscle structure during relaxation

    Science.gov (United States)

    Vazina, A. A.; Gadzhiev, A. M.; Gerasimov, V. S.; Gorbunova, N. P.; Sergienko, P. M.; Korneev, V. N.; Aulchenko, V. M.; Baru, S. E.

    1995-02-01

    The use of the modern time-resolved X-ray diffraction and sample technique has played an important role in studying muscle structures during contraction at various physiological conditions. We represent time-resolved X-ray data on equatorial diffraction and tension response of the frog sartorius muscle during relaxation. The measurements of the time-course of the intensity change of reflections (1,0), (1,1) and the background under them give a possibility to study the effect of potentiation of contraction by repetitive stimulation in fresh and tired muscles. Model calculations of meridional diffraction patterns for various configurations of cross-bridges in the relaxation phase were carried out.

  16. Standard test methods for chemical analysis of ceramic whiteware materials using wavelength dispersive X-Ray fluorescence spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 These test methods cover the determination of ten major elements (SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O, TiO2, P2O5, MnO, and LOI in ceramic whitewares clays and minerals using wavelength dispersive X-ray fluorescence spectrometry (WDXRF). The sample is first ignited, then fused with lithium tetraborate and the resultant glass disc is introduced into a wavelength dispersive X-ray spectrometer. The disc is irradiated with X-rays from an X-ray tube. X-ray photons emitted by the elements in the samples are counted and concentrations determined using previously prepared calibration standards. (1) In addition to 10 major elements, the method provides a gravimetric loss-on-ignition. Note 1—Much of the text of this test method is derived directly from Major element analysis by wavelength dispersive X-ray fluorescence spectrometry, included in Ref (1). 1.2 Interferences, with analysis by WDXRF, may result from mineralogical or other structural effects, line overlaps, and matrix effects. The structure of the...

  17. Total-reflection X-ray fluorescence: An alternative tool for the analysis of magnetic ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Ruiz, R. [Servicio Interdepartamental de Investigacion (SIdI), Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco, E-28049, Madrid (Spain)], E-mail: ramon.fernandez@uam.es; Costo, R.; Morales, M.P.; Bomati-Miguel, O.; Veintemillas-Verdaguer, S. [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049, Madrid (Spain)

    2008-12-15

    This work presents the first application of the total-reflection X-ray fluorescence (TXRF) to the compositional study of magnetic ferrofluids. With the aims of validating the best analytical conditions and also, limitations of the TXRF in the compositional study of these materials, an alternative empirical method, based in the use of angle-dependence TXRF (AD-TXRF) measurements, is proposed. Three kinds of ferromagnetic nanoparticles, with different morphologies, have been studied. The techniques of inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES) have been used to validate the TXRF results. In contrast with the plasma techniques, the developed TXRF procedure need not of previous chemical acid digestion. Additionally, two procedures of magnetic nanoparticles synthesis, co-precipitation and laser-pyrolysis, have been checked for the contaminants trace metals Zn, Mn and Cr. It has been found that the method of laser-pyrolysis produces nanoparticles of higher purity.

  18. Detection of visible and latent fingerprints using micro-X-ray fluorescence elemental imaging.

    Science.gov (United States)

    Worley, Christopher G; Wiltshire, Sara S; Miller, Thomasin C; Havrilla, George J; Majidi, Vahid

    2006-01-01

    Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods.

  19. X-ray spectra of Hercules X-1. I - Iron line fluorescence from a subrelativistic shell

    Science.gov (United States)

    Pravdo, S. H.; Becker, R. H.; Boldt, E. A.; Holt, S. S.; Serlemitsos, P. J.; Swank, J. H.

    1977-01-01

    The X-ray spectrum of Her X-1 was observed in the energy range from 2 to 24 keV from August 29 to September 3, 1975. Emission features are observed near the K-alpha iron-line energy which exhibit both broadening and a double line structure. The total luminosity in these features is about 4 by 10 to the 35th power ergs/s. Iron line fluorescence from an opaque cool (not exceeding 1 million K) shell of material at the Alfven surface provides the necessary luminosity in this feature. The double line structure and the line energy width can be due to Doppler shifts if the shell is forced to corotate with the pulsar at a radius of at least 800 million cm. Implications of this model regarding physical conditions near Her X-1 are discussed.

  20. X-ray fluorescence analysis of wear metals in used lubricating oils

    Science.gov (United States)

    Maddox, W. E.; Kelliher, W. C.

    1986-01-01

    Used oils from several aircraft at NASA's Langley Research Center were analyzed over a three year period using X-ray fluorescence (XRF) and atomic emission spectrometry. The results of both analyses are presented and comparisons are made. Fe and Cu data for oil from four internal combustion engines are provided and XRF and atomic emission spectrometry measurements were found to be in perfect agreement. However, distributions were found in the case of oil from a jet aircraft engine whereby the latter method gave values for total iron concentration in the oil and did not distinguish between suspended particles and oil additives. XRF does not have these particle-size limitations; moreover, it is a faster process. It is concluded that XRF is the preferred method in the construction of a man-portable oil wear analysis instrument.

  1. [Progress in application of microbeam X-ray fluorescence spectroscopy in forensic science].

    Science.gov (United States)

    Su, Hui-Fang; Liu, Chao; Hu, Sun-Lin; Wang, Song-Cai; Sun, Li-Min; Huang, Wei; Zhang, Xiao-Ting; Li, Shuang-Lin

    2013-02-01

    Microbeam X-ray fluorescence (micro-XRF) spectrometry has been raised as an analytical technique of microbeam during the recent years. With its advantages of high sensitivity, small sample requirement, high testing accuracy and non-destruction, the technique is widely utilized in forensic science. This review bases on recent researches at home and abroad, describes its applications including identification of gunshot residue, visualization of fingerprints, discrimination of drug source, production process, and other material evidences of analysis in crime scene. Thanks to the advances in technology, intelligent and portable micro-XRF equipment has appeared to be applied. It is believed that it may be more popular and frequent in administration of forensic science in the near future.

  2. X-Ray Fluorescence to Determine Zn in Bolivian Children using Hair Samples

    Energy Technology Data Exchange (ETDEWEB)

    Tellería Narvaez, C.A.; Fernández Alcázar, S.; Barrientos Zamora, F.G.; Chungara Castro, J.; Luna Lauracia, I.; Mamani Tola, H.; Mita Peralta, E.; Muñoz Gosálvez, A.O. [Centro de Investigaciones y Aplicaciones Nucleares (CIAN-Viacha), Viacha (Bolivia, Plurinational State of); Romero Bolaños, L.E. [Instituto Boliviano de Ciencia y Tecnología Nuclear Av. 6 de Agosto 2905, La Paz (Bolivia, Plurinational State of); Ramírez Ávila, G.M., E-mail: gramirez@ulb.ac.be [Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés, Campus Universitario Cota Cota, Casilla 8635, La Paz (Bolivia, Plurinational State of)

    2014-06-15

    As a first step in the evaluation of nutritional levels in Bolivian children (8–13 years-old), we carried out X-Ray Fluorescence measurements in hair samples of children belonging to different social classes and living either in rural areas or in cities. The aim of this study is to contribute to health policies tending to improve the global health of children and consequently avoid malnutrition. Our method intends to have maximum reliability and at the same time be as simple as possible from an experimental point of view. Additionally, we use this method to determine some other elements such as Fe, Cu, Pb, As and Hg, the latter three considered as contaminants that could be present in children living in areas which neighbor mines and industries. This work will be complemented by some biological and medical tests.

  3. 100-OL-1 Operable Unit Field Portable X-Ray Fluorescence (XRF) Analyzer Pilot Study Plans

    Energy Technology Data Exchange (ETDEWEB)

    Bunn, Amoret L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fritz, Brad G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wellman, Dawn M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-07-01

    A pilot study is being conducted to support the approval of the Remedial Investigation/Feasibility Study (RI/FS) Work Plan to evaluate the 100-OL-1 Operable Unit (OU) pre-Hanford orchard lands. Based on comments received by the U.S. Environmental Protection Agency (EPA) and Washington State Department of Ecology, the pilot study will evaluate the use of field portable X-ray fluorescence (XRF) spectrometry measurements for evaluating lead and arsenic concentrations on the soil surface as an indicator of past use of lead arsenate pesticide residue in the OU. The work will be performed in the field during the summer of 2014, and assist in the planning for the characterization activities in the RI/FS.

  4. Trace element distribution in human teeth by x-ray fluorescence spectrometry and multivariate statistical analysis

    CERN Document Server

    Oprea, Cristiana; Gustova, Marina V; Oprea, Ioan A; Buzguta, Violeta L

    2014-01-01

    X-ray fluorescence spectrometry (XRFS) was used as a multielement method of evaluation of individual whole human tooth or tooth tissues for their amounts of trace elements. Measurements were carried out on human enamel, dentine, and dental cementum, and some differences in tooth matrix composition were noted. In addition, the elemental concentrations determined in teeth from subjects of different ages, nutritional states, professions and gender, living under various environmental conditions and dietary habits, were included in a comparison by multivariate statistical analysis (MVSA) methods. By factor analysis it was established that inorganic components of human teeth varied consistently with their source in the tissue, with more in such tissue from females than in that from males, and more in tooth incisor than in tooth molar.

  5. Metals determination in coffee sample by total reflection X-ray fluorescence analysis (TXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Brienza, Sandra Maria Boscolo [ Universidade Metodista de Piracicaba (UNIMEP), Piracicaba, SP (Brazil). Faculdade de Ciencias Matematicas, da Natureza e de Tecnologia da Informacao]. E-mail: sbrienza@unimep.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Nascimento Filho, Virgilio Franco do [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)]. E-mail: virgilio@cena.usp.br

    2005-07-01

    The objective of this study was to evaluate the inorganic concentration in five brands of coffee, three of them nationally marketed and the others of an exportation kind. The samples were prepared by infusion with deionized water. To carry out the calibration, standard solutions were prepared with different concentrations of Al, Si, K, Ca, Ti, Cr, Fe, Ni, Zn and Se. The measurements were carried out using a white beam of synchrotron radiation for excitation and a Si (Li) semiconductor detector for detection. By employing Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF) it was possible to evaluate the concentrations of P, S, Cl, K, Ca, Mn, Fe, Cu, Zn, Rb and Ba. The detection limits for 300 s counting time were in the range of 0.03 (Ca) to 30 ng.g{sup -1} (Rb), respectively. (author)

  6. In-situ assessment of metal contamination via portable X-ray fluorescence spectroscopy: Zlatna, Romania.

    Science.gov (United States)

    Weindorf, David C; Paulette, Laura; Man, Titus

    2013-11-01

    Zlatna, Romania is the site of longtime mining/smelting operations which have resulted in widespread metal pollution of the entire area. Previous studies have documented the contamination using traditional methods involving soil sample collection, digestion, and quantification via inductively coupled plasma atomic emission spectroscopy or atomic absorption. However, field portable X-ray fluorescence spectroscopy (PXRF) can accurately quantify contamination in-situ, in seconds. A PXRF spectrometer was used to scan 69 soil samples in Zlatna across multiple land use types. Each site was georeferenced with data inputted into a geographic information system for high resolution spatial interpolations. These models were laid over contemporary aerial imagery to evaluate the extent of pollution on an individual elemental basis. Pb, As, Co, Cu, and Cd exceeded governmental action limits in >50% of the sites scanned. The use of georeferenced PXRF data offers a powerful new tool for in-situ assessment of contaminated soils.

  7. Analytic Comparison between X-ray Fluorescence CT and K-edge CT

    CERN Document Server

    Feng, Peng; Cong, Wenxiang; Wei, Biao

    2013-01-01

    X-ray fluorescence computed tomography (XFCT) and K-edge computed tomography (CT) are two important modalities to quantify a distribution of gold nanoparticles (GNPs) in a small animal for preclinical studies. It is valuable to determine which modality is more efficient for a given application. In this paper, we report a theoretical analysis in terms of signal-to-noise ratio (SNR) for the two modalities, showing that there is a threshold for the GNPs concentration and XFCT has a better SNR than K-edge CT if GNPs concentration is less than this threshold. Numerical simulations are performed and two kinds of phantoms are used to represent multiple concentration levels and feature sizes. Experimental results illustrate that XFCT is superior to K-edge CT when contrast concentration is lower than 0.4% which coincides with the theoretical analysis.

  8. [Analysis of 14 elements for Jinhua bergamot by X-ray fluorescence spectrometry and elemental analyser].

    Science.gov (United States)

    Wang, Zhi-gang; Yu, Hong-mei

    2012-01-01

    The content of the elements C, H, O and N in Jinhua bergamot was analysed by using Vario III elemental analyser, the bergamot sample was scanned by using X-ray fluorescence spectrometer with PW2400 wavelength dispersion, and the content of the elements Mg, Al, P, S, Cl, K, Ca, Mn, Fe and Sr was analysed by using IQ+ analytical method. It turned out that the result is more ideal if the content of the elements C, H, O and N is processed as fix phase, and the analytical result is more ideal if, to prevent the sample skin from coming off, the sample is wrapped with mylar film with the film coefficient adjusted.

  9. Elemental Analysis of Variably Contaminated Cremains Using X-ray Fluorescence Spectrometry.

    Science.gov (United States)

    Gilpin, Megan; Christensen, Angi M

    2015-07-01

    Analyzing and identifying skeletal remains becomes increasingly difficult when remains have been cremated, especially in cases where the cremated material may have been intentionally contaminated with nonskeletal material. This study examined the potential of X-ray fluorescence spectrometry (XRF) to detect the presence of nonskeletal contaminants in samples of cremains. Eleven samples of cremains were variably combined with concrete mix and analyzed using XRF. Photon counts of elements in each sample were analyzed, and the coefficient of determination (R(2)) using unweighted linear regression as a function of percent cremains was calculated. Results showed that with changes in the proportion of skeletal material and contaminant, there were significant (R(2) > 0.90) changes in detected levels of phosphorus, potassium, zinc, aluminum, and sulfur. The use of XRF is concluded to be a valid approach in the identification of the presence of nonskeletal material in potentially contaminated cremains.

  10. Confocal X-ray fluorescence micro-spectroscopy experiment in tilted geometry

    Energy Technology Data Exchange (ETDEWEB)

    Czyzycki, Mateusz, E-mail: Mateusz.Czyzycki@desy.de [DESY Photon Science, Notkestr. 85, D-22607 Hamburg (Germany); AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. A. Mickiewicza 30, 30-059 Krakow (Poland); Wrobel, Pawel; Lankosz, Marek [AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. A. Mickiewicza 30, 30-059 Krakow (Poland)

    2014-07-01

    This paper provides a generalized mathematical model to describe the intensity of primary X-ray fluorescence radiation collected in the tilted confocal geometry mode, where the collimating optics is rotated over an angle relative to a horizontal plane. The influence of newly introduced terms, which take into account the tilted geometry mode, is discussed. The model is verified with a multi-layer test sample scanned in depth. It is proved that for low-Z matrices, the rotation of the detection channel does not induce any significant differences in a reconstruction of the thickness and chemical composition of layers, so that it may safely be ignored. - Highlights: • A mathematical model for confocal XRF spectroscopy in tilted geometry was derived. • Tilted geometry influenced the analytical capabilities of XRF instrument slightly. • Thickness and the chemical composition of multi-layers were determined.

  11. Identifying metalloproteins through X-ray fluorescence mapping and mass spectrometry.

    Science.gov (United States)

    Raimunda, Daniel; Khare, Tripti; Giometti, Carol; Vogt, Stefan; Argüello, José M; Finney, Lydia

    2012-08-01

    Metals are critical and dynamic components of biochemistry. To understand their roles, we greatly need tools to identify the ligands that bind them within the complexity of natural systems. This work describes the development of methods that not only detect and distinguish metals, but also characterize the proteins that bind them. We describe an approach to expose, identify and quantify metalloproteins in complex mixtures by sequential non-denaturing 2D-gel electrophoresis (2D GE)/X-ray Fluorescence (XRF) and tandem mass spectrometry (MS/MS) in the same spot of a sample. We first apply the development of 2D GE/XRF to Shewanella oneidensis MR-1, a well-studied system, and verify our electrophoretic approach. Then, we identified a novel periplasmic zinc protein in Pseudomonas aeruginosa PAO1 through 2D GE/XRF followed by MS/MS. The identity and function of this protein was verified through a gene mutation experiment.

  12. Analysis of photographs and photo-paintings by energy-dispersive X-ray fluorescence spectroscopy

    Science.gov (United States)

    Neiva, Augusto Camara; Marcondes, Marli A.; Pinto, Herbert Prince Favero; Almeida, Paula Aline Durães

    2014-02-01

    A collection of Brazilian family photographs and photo-paintings from the beginning of the XX Century was analyzed by portable EDXRF (Energy-Dispersive X-Ray Fluorescence) spectroscopy. The spectrometer uses a Si-drift Amptek detector and an Oxford Cr-tube or an Oxford W-tube. For every region under analysis, spectra obtained with the W-tube were used to detect all the elements above Al, while the Cr-tube was used to obtain more accurate results for elements between Al and V. Thirty nine elements were identified in the photos, and the origin of the most important ones was discussed. These results can be used for cataloging, preservation and restoring procedures.

  13. Mapping metals in Parkinson's and normal brain using rapid-scanning x-ray fluorescence

    Science.gov (United States)

    Popescu, Bogdan F. Gh; George, Martin J.; Bergmann, Uwe; Garachtchenko, Alex V.; Kelly, Michael E.; McCrea, Richard P. E.; Lüning, Katharina; Devon, Richard M.; George, Graham N.; Hanson, Akela D.; Harder, Sheri M.; Chapman, L. Dean; Pickering, Ingrid J.; Nichol, Helen

    2009-02-01

    Rapid-scanning x-ray fluorescence (RS-XRF) is a synchrotron technology that maps multiple metals in tissues by employing unique hardware and software to increase scanning speed. RS-XRF was validated by mapping and quantifying iron, zinc and copper in brain slices from Parkinson's disease (PD) and unaffected subjects. Regions and structures in the brain were readily identified by their metal complement and each metal had a unique distribution. Many zinc-rich brain regions were low in iron and vice versa. The location and amount of iron in brain regions known to be affected in PD agreed with analyses using other methods. Sample preparation is simple and standard formalin-fixed autopsy slices are suitable. RS-XRF can simultaneously and non-destructively map and quantify multiple metals and holds great promise to reveal metal pathologies associated with PD and other neurodegenerative diseases as well as diseases of metal metabolism.

  14. First Total Reflection X-Ray Fluorescence round-robin test of water samples: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Borgese, Laura; Bilo, Fabjola [Chemistry for Technologies Laboratory, University of Brescia, Brescia (Italy); Tsuji, Kouichi [Graduate School of Engineering, Osaka City University, Osaka (Japan); Fernández-Ruiz, Ramón [Servicio Interdepartamental de Investigación (SIdI), Laboratorio de TXRF, Universidad Autónoma de Madrid, Madrid (Spain); Margui, Eva [Department of Chemistry, University of Girona, Girona (Spain); Streli, Christina [TU Wien, Atominstitut,Radiation Physics, Vienna (Austria); Pepponi, Giancarlo [Fondazione Bruno Kessler, Povo, Trento (Italy); Stosnach, Hagen [Bruker Nano GmbH, Berlin (Germany); Yamada, Takashi [Rigaku Corporation, Takatsuki, Osaka (Japan); Vandenabeele, Peter [Department of Archaeology, Ghent University, Ghent (Belgium); Maina, David M.; Gatari, Michael [Institute of Nuclear Science and Technology, University of Nairobi, Nairobi (Kenya); Shepherd, Keith D.; Towett, Erick K. [World Agroforestry Centre (ICRAF), Nairobi (Kenya); Bennun, Leonardo [Laboratorio de Física Aplicada, Departamento de Física, Universidad de Concepción (Chile); Custo, Graciela; Vasquez, Cristina [Gerencia Química, Laboratorio B025, Centro Atómico Constituyentes, San Martín (Argentina); Depero, Laura E., E-mail: laura.depero@unibs.it [Chemistry for Technologies Laboratory, University of Brescia, Brescia (Italy)

    2014-11-01

    Total Reflection X-Ray Fluorescence (TXRF) is a mature technique to evaluate quantitatively the elemental composition of liquid samples deposited on clean and well polished reflectors. In this paper the results of the first worldwide TXRF round-robin test of water samples, involving 18 laboratories in 10 countries are presented and discussed. The test was performed within the framework of the VAMAS project, interlaboratory comparison of TXRF spectroscopy for environmental analysis, whose aim is to develop guidelines and a standard methodology for biological and environmental analysis by means of the TXRF analytical technique. - Highlights: • The discussion of the first worldwide TXRF round-robin test of water samples (18 laboratories of 10 countries) is reported. • Drinking, waste, and desalinated water samples were tested. • Data dispersion sources were identified: sample concentration, preparation, fitting procedure, and quantification. • The protocol for TXRF analysis of drinking water is proposed.

  15. Performance of a Borehole X-ray Fluorescence Spectrometer for Planetary Exploration

    Science.gov (United States)

    Kelliher, Warren C.; Carlberg, Ingrid A.; Elam, W. T.; Willard-Schmoe, Ella

    2008-01-01

    We have designed and constructed a borehole X-ray Fluorescence Spectrometer (XRFS) as part of the Mars Subsurface Access program [1]. It can be used to determine the composition of the Mars regolith at various depths by insertion into a pre-drilled borehole. The primary requirements and performance metrics for the instrument are to obtain parts-per-million (ppm) lower limits of detection over a wide range of elements in the periodic table (Magnesium to Lead). Power consumption during data collection was also measured. The prototype instrument is complete and preliminary testing has been performed. Terrestrial soil Standard Reference Materials were used as the test samples. Detection limits were about 10 weight ppm for most elements, with light elements being higher, up to 1.4 weight percent for magnesium. Power consumption (excluding ground support components) was 12 watts.

  16. Diagnosing Direct-Drive, Shock-Heated, and Compressed Plastic Planar Foils with Noncollective Spectrally Resolved X-Ray Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, H.; Regan, S.P.; Meyerhofer, D.D.; Igumenshchev, I.V.; Goncharov, V.N.; Boehly, T.R.; Epstein, R.; Sangster, T.C.; Smalyuk, V.A.; Yaakobi, B.; Gregori, G.; Glenzer, S.H.; Landen, O.L.

    2007-12-14

    The electron temperature (Te) and average ionization (Z) of nearly Fermi-degenerate, direct-drive, shock-heated, and compressed plastic planar foils were investigated using noncollective spectrally resolved x-ray scattering on the OMEGA Laser System. Plastic (CH) and Br-doped CH foils were driven with six beams, having an overlapped intensity of ~1 × 10^14 W/cm^2 and generating ~15-Mbar pressure in the foil.

  17. Critical-angle x-ray transmission grating spectrometer with extended bandpass and resolving power > 10,000

    Science.gov (United States)

    Heilmann, Ralf K.; Bruccoleri, Alexander R.; Kolodziejczak, Jeffery; Gaskin, Jessica A.; O'Dell, Stephen L.; Bhatia, Ritwik; Schattenburg, Mark L.

    2016-07-01

    A number of high priority subjects in astrophysics can be addressed by a state-of-the-art soft x-ray grating spectrometer, such as the role of Active Galactic Nuclei in galaxy and star formation, characterization of the Warm-Hot Intergalactic Medium and the missing baryon problem, characterization of halos around the Milky Way and nearby galaxies, as well as stellar coronae and surrounding winds and disks. An Explorer-scale, largearea (> 1,000 cm2), high resolving power (R =λ/Δλ > 3,000) soft x-ray grating spectrometer is highly feasible based on Critical-Angle Transmission (CAT) grating technology, even for telescopes with angular resolution of 5-10 arcsec. Still, significantly higher performance can be provided by a CAT grating spectrometer on an X-ray- Surveyor-type mission. CAT gratings combine the advantages of blazed reflection gratings (high efficiency, use of higher diffraction orders) with those of conventional transmission gratings (lowmass, relaxed alignment tolerances and temperature requirements, transparent at higher energies) with minimalmission resource requirements. They are high-efficiency blazed transmission gratings that consist of freestanding, ultra-high aspect-ratio grating bars fabricated from silicon-on-insulator (SOI) wafers using advanced anisotropic dry and wet etch techniques. Blazing is achieved through grazing-incidence reflection off the smooth grating bar sidewalls. The reflection properties of silicon are well matched to the soft x-ray band, and existing silicon CAT gratings can exceed 30% absolute diffraction efficiency, with clear paths for further improvement. Nevertheless, CAT gratings with sidewalls made of higher atomic number elements allow extension of the CAT grating principle to higher energies and larger dispersion angles, thus enabling higher resolving power at shorter wavelengths. We show x-ray data from CAT gratings coated with a thin layer of platinum using atomic layer deposition, and demonstrate efficient

  18. Elementary chemical analysis in leaves infected by fumagina by X-Ray fluorescence technique

    Directory of Open Access Journals (Sweden)

    Maria Sélia Blonski

    2007-09-01

    Full Text Available Energy Dispersion X-Ray Fluorescence Technique (EDXRF was employed to study the effects of the fumagina disease on the elementary chemical composition of the leaves. The experimental set up consisted of a Mo X-ray tube (Ksubµ = 17.44 keV with Zr filter and a Si (Li detector. The measurements were performed with the infected and healthy leaves of citric plants. The elements Ti, Mn, Fe, Cu and Zn were quantified, with an average DL of 69, 12, 8, 4 and 4 µg.g-1 respectively. The obtained concentration for Fe varied from 44 to 192 µg.g-1 in healthy leaves and from 363 to 704 µg.g-1 in infected leaves with fumagina .Foi empregada a técnica de fluorescência de raios X por dispersão de energia (EDXRF, para estudar os efeitos da doença fumagina na composição química elementar de folhas. O arranjo experimental consistiu de um tubo de raios X com anodo de Mo (Kµ = 17.44 keV com filtro de Zr e um detector de Si(Li. As medidas foram realizadas com folhas de plantas cítricas infectadas e sadias. Foram quantificados os elementos Ti, Mn, Fe, Cu e Zn, com um limite de detecção médio de 69, 12, 8, 4 e 4 µg.g-1 respectivamente. As concentrações obtidas para o Fe variaram de 44 a 192 µg.g-1 em amostras de folhas sadias e de 363 a 704 µg g-1 para as folhas infectadas com fumagina.

  19. Identifying microbial habitats in soil using quantum dots and x-ray fluorescence microtomography

    Science.gov (United States)

    O'Brien, S. L.; Whiteside, M. D.; Sholto-Douglas, D.; Dohnalkova, A.; Durall, D. M.; Gursoy, D.; Jones, M. D.; Kovarik, L.; Lai, B.; Roehrig, C.; Sullivan, S.; Vogt, S.; Kemner, K. M.

    2015-12-01

    The metabolic activities of soil microbes are the primary drivers of biogeochemical processes controlling the terrestrial carbon cycle, nutrient availability to plants, contaminant remediation, water quality, and other ecosystem services. However, we have a limited understanding of microbial metabolic processes such as nutrient uptake rates, substrate preferences, or how microbes and microbial metabolism are distributed throughout the three-dimensional pore network of the soil. Here we use a novel combination of imaging techniques with quantum dots (QDs, engineered semiconductor nanoparticles that produce size or composition-dependent fluorescence) to locate bacteria in the three-dimensional pore network of a soil aggregate. First, we show using confocal and aberration-corrected transmission electron microscopies that bacteria (Bacillus subtilis, Pseudomonas fluorescens, and Pseudomonas protogens) actively take up and internalize CdSe/ZnS core/shell QDs conjugated to biologically relevant substrates. Next, we show that cells bearing QDs can be identified using fluorescence imaging with hard x-rays at 2ID-D at the Advanced Photon Source (APS). Finally, we demonstrate that the Se constituent to the QDs can be used to label bacteria in three-dimensional tomographic reconstructions of natural soil at 0.5 nm spatial resolution using hard x-rays at 2ID-E at the APS. This is the first time soil bacteria have been imaged in the intact soil matrix at such high resolution. These results offer a new way to experimentally investigate basic bacterial ecology in situ, revealing constraints on microbial function in soil that will help improve connections between pore-scale and ecosystem-scale processes in models.

  20. High resolution X-ray fluorescence imaging for a microbeam radiation therapy treatment planning system

    Science.gov (United States)

    Chtcheprov, Pavel; Inscoe, Christina; Burk, Laurel; Ger, Rachel; Yuan, Hong; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-03-01

    Microbeam radiation therapy (MRT) uses an array of high-dose, narrow (~100 μm) beams separated by a fraction of a millimeter to treat various radio-resistant, deep-seated tumors. MRT has been shown to spare normal tissue up to 1000 Gy of entrance dose while still being highly tumoricidal. Current methods of tumor localization for our MRT treatments require MRI and X-ray imaging with subject motion and image registration that contribute to the measurement error. The purpose of this study is to develop a novel form of imaging to quickly and accurately assist in high resolution target positioning for MRT treatments using X-ray fluorescence (XRF). The key to this method is using the microbeam to both treat and image. High Z contrast media is injected into the phantom or blood pool of the subject prior to imaging. Using a collimated spectrum analyzer, the region of interest is scanned through the MRT beam and the fluorescence signal is recorded for each slice. The signal can be processed to show vascular differences in the tissue and isolate tumor regions. Using the radiation therapy source as the imaging source, repositioning and registration errors are eliminated. A phantom study showed that a spatial resolution of a fraction of microbeam width can be achieved by precision translation of the mouse stage. Preliminary results from an animal study showed accurate iodine profusion, confirmed by CT. The proposed image guidance method, using XRF to locate and ablate tumors, can be used as a fast and accurate MRT treatment planning system.

  1. Uranium and plutonium solution assays by transmission-corrected x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Ryon, R W; Ruhter, W D; Rudenko, V; Sirontinin, A; Petrov, A A

    1999-09-08

    We have refined and tested a previously developed x-ray fluorescence analysis technique for uranium and plutonium solutions that compensates for variations in the absorption of the exciting gamma rays and fluorescent x-rays. We use {sup 57}Co to efficiently excite the K lines of the elements, and a mixed {sup 57}Co plus {sup 153}Gd transmission source to correct for variations in absorption. The absorption correction is a unique feature of our technique. It is possible to accurately calibrate the system with a single solution standard. There does not need to be a close match in composition (i.e., absorption) between the standard(s) and solutions to be analyzed. Specially designed equipment incorporates a planar intrinsic germanium detector, excitation and transmission radioisotopes, and specimen holder. The apparatus can be inserted into a rubber glove of a glovebox, keeping the apparatus outside and the solutions inside the glovebox, thereby protecting the user and the equipment from possible contamination. An alternate design may be used in chemical reprocessing plants, providing continuous monitoring, by measuring the trans-actinides through stainless steel piping. This technique has been tested at the Bochvar Research Institute of Inorganic Materials in Moscow for possible use in the Russian complex of nuclear facilities. This is part of a cooperative program between laboratories in the United States and Russia to strengthen systems of nuclear materials protection, control, and accountability (MPC and A). A part of this program is to accurately measure and track inventories of materials, thus the need for good non-destructive analytical techniques such as the one described here.

  2. Quantitative micro x-ray fluorescence analyses without reference standard material; Referenzprobenfreie quantitative Mikro-Roentgenfluoreszenzanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Timo

    2009-07-15

    X-ray fluorescence analysis (XRF) is a standard method for non-destructive investigations. Due to the development of polycapillary optics and SDDdetectors requiring no cooling with liquid nitrogen, XRF becomes a suitable method for a large number of applications, e. g. for the analysis of objects in arts and archaeology. Spectrometers developed for those purposes allow investigations outside of laboratories und provide excitation areas with diameters of 10-70 {mu}m. In most applications, quantification of XRF data is realized by the usage of standard reference materials. Due to absorption processes in the samples the accuracy of the results depends strongly on the similarity of the sample and the reference standard. In cases where no suitable references are available, quantification can be done based on the ''fundamental parameter (fp) method''. This quantification procedure is based on a set of equations describing the fluorescence production and detection mathematical. The cross sections for the interaction of x-rays with matter can be taken from different databases. During an iteration process the element concentrations can be determined. Quantitative XRF based on fundamental parameters requires an accurate knowledge of the excitation spectrum. In case of a conventional setup this spectrum is given by the X-ray tube spectrum and can be calculated. The use of polycapillary optics in micro-XRF spectrometers changes the spectral distribution of the excitation radiation. For this reason it is necessary to access the transmission function of the used optic. The aim of this work is to find a procedure to describe this function for routine quantification based on fundamental parameters. Most of the measurements have been carried out using a commercial spectrometer developed for applications in arts and archaeology. On the one hand the parameters of the lens, used in the spectrometer, have been investigated by different experimental characterization

  3. X-ray fluorescence imaging reveals subcellular biometal disturbances in a childhood neurodegenerative disorder.

    Science.gov (United States)

    Grubman, A; James, S A; James, J; Duncan, C; Volitakis, I; Hickey, J L; Crouch, P J; Donnelly, P S; Kanninen, K M; Liddell, J R; Cotman, S L; de Jonge; White, A R

    2014-06-01

    Biometals such as zinc, iron, copper and calcium play key roles in diverse physiological processes in the brain, but can be toxic in excess. A hallmark of neurodegeneration is a failure of homeostatic mechanisms controlling the concentration and distribution of these elements, resulting in overload, deficiency or mislocalization. A major roadblock to understanding the impact of altered biometal homeostasis in neurodegenerative disease is the lack of rapid, specific and sensitive techniques capable of providing quantitative subcellular information on biometal homeostasis in situ. Recent advances in X-ray fluorescence detectors have provided an opportunity to rapidly measure biometal content at subcellular resolution in cell populations using X-ray Fluorescence Microscopy (XFM). We applied this approach to investigate subcellular biometal homeostasis in a cerebellar cell line isolated from a natural mouse model of a childhood neurodegenerative disorder, the CLN6 form of neuronal ceroid lipofuscinosis, commonly known as Batten disease. Despite no global changes to whole cell concentrations of zinc or calcium, XFM revealed significant subcellular mislocalization of these important biological second messengers in cerebellar Cln6(nclf) (CbCln6(nclf) ) cells. XFM revealed that nuclear-to-cytoplasmic trafficking of zinc was severely perturbed in diseased cells and the subcellular distribution of calcium was drastically altered in CbCln6(nclf) cells. Subtle differences in the zinc K-edge X-ray Absorption Near Edge Structure (XANES) spectra of control and CbCln6(nclf) cells suggested that impaired zinc homeostasis may be associated with an altered ligand set in CbCln6(nclf) cells. Importantly, a zinc-complex, Zn(II)(atsm), restored the nuclear-to-cytoplasmic zinc ratios in CbCln6(nclf) cells via nuclear zinc delivery, and restored the relationship between subcellular zinc and calcium levels to that observed in healthy control cells. Zn(II)(atsm) treatment also resulted in a

  4. Characterization of X-ray polycapillary optics by LiF crystal radiation detectors through confocal fluorescence microscopy

    Science.gov (United States)

    Bonfigli, Francesca; Hampai, Dariush; Dabagov, Sultan B.; Montereali, Rosa Maria

    2016-08-01

    Solid-state radiation imaging detectors based on photoluminescent colour centres in lithium fluoride (LiF) crystals have been successfully tested for both advanced 2D and 3D characterizations of X-ray polycapillary optics by a table-top laboratory system. Polycapillary optics can control X-ray beams propagation and allows obtaining quasi-parallel beam (half-lens) or focused beams (full-lens). The combination of a fine-focused micro X-ray tube and a polycapillary lens can provide the high intensity radiation fluxes that are necessary for high resolution X-ray imaging. In this paper we present novel results about advanced characterization of these complex optics by 2D as well as 3D confocal laser fluorescence microscopy of X-ray irradiated LiF crystal detectors. Two dimensional high spatial resolution images on a wide field of view of transmitted X-rays through a semi-lens and 3D direct inspection of the coloured volumes produced in LiF crystals by both focused and parallel X-ray beam transmitted by a full and a semi-lens, respectively, as well as their 3D reconstructions were obtained. The results show that the photoluminescent colour centres volume in LiF crystals combined with an optical sectioning reading system provide information about tomography of transmitted X-ray beams by policapillary optics in a single exposure process. For the first time, the use of LiF crystal plates as versatile radiation imaging luminescent detectors have been used to characterize the operation of polycapillary optics as X-ray lens, in focusing and parallel mode.

  5. FY05 LDRD Final ReportTime-Resolved Dynamic Studies using Short Pulse X-Ray Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A; Dunn, J; van Buuren, T; Budil, K; Sadigh, B; Gilmer, G; Falcone, R; Lee, R; Ng, A

    2006-02-10

    Established techniques must be extended down to the ps and sub-ps time domain to directly probe product states of materials under extreme conditions. We used short pulse ({le} 1 ps) x-ray radiation to track changes in the physical properties in tandem with measurements of the atomic and electronic structure of materials undergoing fast laser excitation and shock-related phenomena. The sources included those already available at LLNL, including the picosecond X-ray laser as well as the ALS Femtosecond Phenomena beamline and the SSRL based sub-picosecond photon source (SPPS). These allow the temporal resolution to be improved by 2 orders of magnitude over the current state-of-the-art, which is {approx} 100 ps. Thus, we observed the manifestations of dynamical processes with unprecedented time resolution. Time-resolved x-ray photoemission spectroscopy and x-ray scattering were used to study phase changes in materials with sub-picosecond time resolution. These experiments coupled to multiscale modeling allow us to explore the physics of materials in high laser fields and extreme non-equilibrium states of matter. The ability to characterize the physical and electronic structure of materials under extreme conditions together with state-of-the-art models and computational facilities will catapult LLNL's core competencies into the scientific world arena as well as support its missions of national security and stockpile stewardship.

  6. Data collection strategies for time-resolved X-ray free-electron laser diffraction, and 2-color methods.

    Science.gov (United States)

    Li, Chufeng; Schmidt, Kevin; Spence, John C

    2015-07-01

    We compare three schemes for time-resolved X-ray diffraction from protein nanocrystals using an X-ray free-electron laser. We find expressions for the errors in structure factor measurement using the Monte Carlo pump-probe method of data analysis with a liquid jet, the fixed sample pump-probe (goniometer) method (both diffract-and-destroy, and below the safe damage dose), and a proposed two-color method. Here, an optical pump pulse arrives between X-ray pulses of slightly different energies which hit the same nanocrystal, using a weak first X-ray pulse which does not damage the sample. (Radiation damage is outrun in the other cases.) This two-color method, in which separated Bragg spots are impressed on the same detector readout, eliminates stochastic fluctuations in crystal size, shape, and orientation and is found to require two orders of magnitude fewer diffraction patterns than the currently used Monte Carlo liquid jet method, for 1% accuracy. Expressions are given for errors in structure factor measurement for the four approaches, and detailed simulations provided for cathepsin B and IC3 crystals. While the error is independent of the number of shots for the dose-limited goniometer method, it falls off inversely as the square root of the number of shots for the two-color and Monte Carlo methods, with a much smaller pre-factor for the two-color mode, when the first shot is below the damage threshold.

  7. 2D/3D cryo x-ray fluorescence imaging at the bionanoprobe at the advanced photon source

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S., E-mail: sichen@aps.anl.gov; Vine, D. J.; Lai, B. [Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439 (United States); Paunesku, T.; Yuan, Y.; Woloschak, G. E. [Department of Radiation Oncology, Northwester University, Chicago, IL 60611 (United States); Deng, J. [Applied Physics, Northwestern University, Evanston, IL 60208 (United States); Jin, Q.; Hong, Y. P. [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Flachenecker, C.; Hornberger, B. [Carl Zeiss X-ray Microscopy, Pleasanton, CA 94588 (United States); Brister, K. [Synchrotron Research Center, Northwestern University, Argonne, IL 60439 (United States); Jacobsen, C. [Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439 (United States); Applied Physics, Northwestern University, Evanston, IL 60208 (United States); Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208 (United States); Vogt, S. [Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439 (United States); Department of Radiation Oncology, Northwester University, Chicago, IL 60611 (United States)

    2016-01-28

    Trace elements, particularly metals, play very important roles in biological systems. Synchrotron-based hard X-ray fluorescence microscopy offers the most suitable capabilities to quantitatively study trace metals in thick biological samples, such as whole cells and tissues. In this manuscript, we have demonstrated X-ray fluorescence imaging of frozen-hydrated whole cells using the recent developed Bionanoprobe (BNP). The BNP provides spatial resolution down to 30 nm and cryogenic capabilities. Frozen-hydrated biological cells have been directly examined on a sub-cellular level at liquid nitrogen temperatures with minimal sample preparation.

  8. Investigation of time-resolved proton radiography using x-ray flat-panel imaging system

    Science.gov (United States)

    Jee, K.-W.; Zhang, R.; Bentefour, E. H.; Doolan, P. J.; Cascio, E.; Sharp, G.; Flanz, J.; Lu, H.-M.

    2017-03-01

    Proton beam therapy benefits from the Bragg peak and delivers highly conformal dose distributions. However, the location of the end-of-range is subject to uncertainties related to the accuracy of the relative proton stopping power estimates and thereby the water-equivalent path length (WEPL) along the beam. To remedy the range uncertainty, an in vivo measurement of the WEPL through the patient, i.e. a proton-range radiograph, is highly desirable. Towards that goal, we have explored a novel method of proton radiography based on the time-resolved dose measured by a flat panel imager (FPI). A 226 MeV pencil beam and a custom-designed range modulator wheel (MW) were used to create a time-varying broad beam. The proton imaging technique used exploits this time dependency by looking at the dose rate at the imager as a function of time. This dose rate function (DRF) has a unique time-varying dose pattern at each depth of penetration. A relatively slow rotation of the MW (0.2 revolutions per second) and a fast image acquisition (30 frames per second, ~33 ms sampling) provided a sufficient temporal resolution for each DRF. Along with the high output of the CsI:Tl scintillator, imaging with pixel binning (2  ×  2) generated high signal-to-noise data at a very low radiation dose (~0.1 cGy). Proton radiographs of a head phantom and a Gammex CT calibration phantom were taken with various configurations. The results of the phantom measurements show that the FPI can generate low noise and high spatial resolution proton radiographs. The WEPL values of the CT tissue surrogate inserts show that the measured relative stopping powers are accurate to ~2%. The panel did not show any noticeable radiation damage after the accumulative dose of approximately 3831 cGy. In summary, we have successfully demonstrated a highly practical method of generating proton radiography using an x-ray flat panel imager.

  9. Sub-nanosecond time-resolved ambient-pressure X-ray photoelectron spectroscopy setup for pulsed and constant wave X-ray light sources.

    Science.gov (United States)

    Shavorskiy, Andrey; Neppl, Stefan; Slaughter, Daniel S; Cryan, James P; Siefermann, Katrin R; Weise, Fabian; Lin, Ming-Fu; Bacellar, Camila; Ziemkiewicz, Michael P; Zegkinoglou, Ioannis; Fraund, Matthew W; Khurmi, Champak; Hertlein, Marcus P; Wright, Travis W; Huse, Nils; Schoenlein, Robert W; Tyliszczak, Tolek; Coslovich, Giacomo; Robinson, Joseph; Kaindl, Robert A; Rude, Bruce S; Ölsner, Andreas; Mähl, Sven; Bluhm, Hendrik; Gessner, Oliver

    2014-09-01

    An apparatus for sub-nanosecond time-resolved ambient-pressure X-ray photoelectron spectroscopy studies with pulsed and constant wave X-ray light sources is presented. A differentially pumped hemispherical electron analyzer is equipped with a delay-line detector that simultaneously records the position and arrival time of every single electron at the exit aperture of the hemisphere with ~0.1 mm spatial resolution and ~150 ps temporal accuracy. The kinetic energies of the photoelectrons are encoded in the hit positions along the dispersive axis of the two-dimensional detector. Pump-probe time-delays are provided by the electron arrival times relative to the pump pulse timing. An average time-resolution of (780 ± 20) ps (FWHM) is demonstrated for a hemisphere pass energy E(p) = 150 eV and an electron kinetic energy range KE = 503-508 eV. The time-resolution of the setup is limited by the electron time-of-flight (TOF) spread related to the electron trajectory distribution within the analyzer hemisphere and within the electrostatic lens system that images the interaction volume onto the hemisphere entrance slit. The TOF spread for electrons with KE = 430 eV varies between ~9 ns at a pass energy of 50 eV and ~1 ns at pass energies between 200 eV and 400 eV. The correlation between the retarding ratio and the TOF spread is evaluated by means of both analytical descriptions of the electron trajectories within the analyzer hemisphere and computer simulations of the entire trajectories including the electrostatic lens system. In agreement with previous studies, we find that the by far dominant contribution to the TOF spread is acquired within the hemisphere. However, both experiment and computer simulations show that the lens system indirectly affects the time resolution of the setup to a significant extent by inducing a strong dependence of the angular spread of electron trajectories entering the hemisphere on the retarding ratio. The scaling of the angular spread with

  10. X-ray nanoprobes and diffraction-limited storage rings: opportunities and challenges of fluorescence tomography of biological specimens

    Energy Technology Data Exchange (ETDEWEB)

    Jonge, Martin D. de, E-mail: martin.dejonge@synchrotron.org.au [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia); Ryan, Christopher G. [CSIRO Earth Science and Research Engineering, Clayton, Victoria 3168 (Australia); Jacobsen, Chris J. [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Department of Physics, Chemistry of Life Processes Institute, Northwestern University, 2170 Campus Drive, Evanston, IL 60208 (United States); Chemistry of Life Processes Institute, Northwestern University, 2170 Campus Drive, Evanston, IL 60208 (United States)

    2014-08-27

    Nanoscale X-ray scanning microscopes, or X-ray nanoprobes, will benefit greatly from diffraction-limited storage rings. Here the requirements for nanoscale fluorescence tomography are explored to gain insight into the scientific opportunities and technical challenges that such sources offer. X-ray nanoprobes require coherent illumination to achieve optic-limited resolution, and so will benefit directly from diffraction-limited storage rings. Here, the example of high-resolution X-ray fluorescence tomography is focused on as one of the most voracious demanders of coherent photons, since the detected signal is only a small fraction of the incident flux. Alternative schemes are considered for beam delivery, sample scanning and detectors. One must consider as well the steps before and after the X-ray experiment: sample preparation and examination conditions, and analysis complexity due to minimum dose requirements and self-absorption. By understanding the requirements and opportunities for nanoscale fluorescence tomography, one gains insight into the R&D challenges in optics and instrumentation needed to fully exploit the source advances that diffraction-limited storage rings offer.

  11. Method of time resolved refractive index measurements of x-ray laser heated solids

    Energy Technology Data Exchange (ETDEWEB)

    Williams, G. O.; Kuenzel, S.; Fajardo, M. [GoLP/Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal); Chung, H.-K. [Atomic and Molecular Data Unit, Nuclear Data Section, IAEA, PO Box 100, A-1400 Vienna (Austria); Vinko, S. M. [Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Sardinha, A. B. [GoLP/Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal); Laboratoire d' Optique Appliquee, Ecole Nationale Superieure de Technique Avancees, Ecole Polytechnique, CNRS UMR7639, Chemin de la Huniere, 91761 Palaiseau Cedex (France); Zeitoun, Ph. [Laboratoire d' Optique Appliquee, Ecole Nationale Superieure de Technique Avancees, Ecole Polytechnique, CNRS UMR7639, Chemin de la Huniere, 91761 Palaiseau Cedex (France)

    2013-04-15

    With the advent of new x-ray light-sources worldwide, the creation of dense, uniformly heated plasma states arising from intense x-ray irradiation of solids has been made possible. In the early stages of x-ray solid heating, before significant hydrodynamic motion occurs, the matter exists in a highly non-equilibrium state. A method based on wavefront sensing is proposed to probe some of the fundamental properties of these states. The deflection and absorption of a high harmonic probe beam propagated through the plasma can be measured with a wavefront sensor, and allow for the determination of the complex refractive index (RI) of the plasma, giving a 2D map of the optical properties as function of time in a pump-probe arrangement. A solid heating model has been used to estimate the expected temperatures of x-ray heated thin foils, and these temperatures are used in three separate models to estimate the changes in the refractive index. The calculations show the changes induced on an extreme ultra-violet (XUV) probe beam by a solid density thin foil plasma are significant, in terms of deflection angle and absorption, to be measured by already existing XUV Hartmann wavefront sensors. The method is applicable to a wide range of photon energies in the XUV (10 s to several 100 s of eV) and plasma parameters, and can add much needed experimental data to the fundamental properties of such dense plasma states.

  12. Chandra Phase-Resolved X-ray Spectroscopy of the Crab Pulsar II

    CERN Document Server

    Weisskopf, Martin C; Yakovlev, Dmitry G; Harding, Alice; Zavlin, Vyacheslav E; O'Dell, Stephen L; Elsner, Ronald F; Becker, Werner

    2011-01-01

    We present a new study of the X-ray spectral properties of the Crab Pulsar. The superb angular resolution of the Chandra X-ray Observatory enables distinguishing the pulsar from the surrounding nebulosity. Analysis of the spectrum as a function of pulse phase allows the least-biased measure of interstellar X-ray extinction due primarily to photoelectric absorption and secondarily to scattering by dust grains in the direction of the Crab Nebula. We modify previous findings that the line-of-sight to the Crab is under-abundant in oxygen and provide measurements with improved accuracy and less bias. Using the abundances and cross sections from Wilms, Allen & McCray (2000) we find [O/H] = $(5.28 \\pm 0.28)\\times10^{-4}$ ($4.9 \\times10^{-4}$ is solar abundance). We also measure for the first time the impact of scattering of flux out of the image by interstellar grains. We find $\\tau_{\\rm scat} = 0.147 \\pm 0.043$. Analysis of the spectrum as a function of pulse phase also measures the X-ray spectral index even at...

  13. Resolved atomic lines reveal outflows in two ultraluminous X-ray sources

    CERN Document Server

    Pinto, Ciro; Fabian, Andrew C

    2016-01-01

    Ultraluminous X-ray sources are extragalactic, off-nucleus, point sources in galaxies with an X-ray luminosity above 3x10^39 erg/s, thought to be powered by accretion onto a compact object. Possible explanations include accretion onto neutron stars with strong magnetic fields, stellar-mass black holes ( 5 sigma, and blueshifted (~0.2c) absorption lines (5 sigma) in the high-resolution X-ray spectrum of the ultraluminous X-ray source NGC 1313 X-1. In a similar source, NGC 5408 X-1, we also detect emission lines at rest and blueshifted absorption. The blueshifted absorption lines must occur in a fast outflowing gas, whereas the emission lines originate in slow-moving gas around the source. We conclude that the compact object is surrounded by powerful winds with an outflow velocity of about 0.2c as predicted by models of accreting supermassive black holes and hyper-accreting stellar mass black holes.

  14. X-Ray Diffraction (XRD and X-Ray Fluorescence (XRF Analysis of Proto-historic Votive Tablets from Chawas Cave, Hulu Kelantan, Malaysia

    Directory of Open Access Journals (Sweden)

    Zuliskandar Ramli

    2014-02-01

    Full Text Available This research was conducted to determine the origin of votive tablets found in prehistoric and proto-historic site of Chawas Cave in Hulu Kelantan. The votive tablets found in Chawas Cave showed several Buddhist images which are associated with the Srivijaya Kingdom which existed from 7th century AD until 12th century AD. To determine if the votive tablets were produced by communities that lived in Hulu Kelantan, hence the study of the chemical composition of the votive tablets should be carried out. Two techniques were employed in this research, namely the X-Ray Diffraction (XRD and X-Ray Fluorescence (XRF techniques. The techniques will determine the mineral content as well as the major and trace element content of the votive tablets. Analysis showed that all the votive tablet samples have mineral known as clinochlore. Clinochlore is one of the chlorites, namely a group of phyllosilicate minerals. Chlorite is commonly found in igneous rocks as an alteration product of mafic minerals such as pyroxene, amphibole and biotite. The votive tablets were found in a cave which consisted of limestone cave formation and it showed that the votive tablets were not produced by the local community of Hulu Kelantan. Major elements also showed that the chemical composition of the votive tablets is not similar to the composition of clay samples taken from several rivers in Hulu Kelantan.

  15. Iron speciation in human cancer cells by K-edge total reflection X-ray fluorescence-X-ray absorption near edge structure analysis

    Energy Technology Data Exchange (ETDEWEB)

    Polgari, Zs. [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary); Meirer, F. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); MiNALab, CMM-irst, Fondazione Bruno Kessler, Povo, Trento (Italy); Sasamori, S.; Ingerle, D. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); Pepponi, G. [MiNALab, CMM-irst, Fondazione Bruno Kessler, Povo, Trento (Italy); Streli, C. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); Rickers, K. [Hamburger Synchrotronstrahlungslabor at DESY, Hamburg (Germany); Reti, A.; Budai, B. [Department of Clinical Research, National Institute of Oncology, Budapest (Hungary); Szoboszlai, N. [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary); Zaray, G., E-mail: zaray@ludens.elte.hu [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary)

    2011-03-15

    X-ray absorption near edge structure (XANES) analysis in combination with synchrotron radiation induced total reflection X-ray fluorescence (SR-TXRF) acquisition was used to determine the oxidation state of Fe in human cancer cells and simultaneously their elemental composition by applying a simple sample preparation procedure consisting of pipetting the cell suspension onto the quartz reflectors. XANES spectra of several inorganic and organic iron compounds were recorded and compared to that of different cell lines. The XANES spectra of cells, independently from the phase of cell growth and cell type were very similar to that of ferritin, the main Fe store within the cell. The spectra obtained after CoCl{sub 2} or NiCl{sub 2} treatment, which could mimic a hypoxic state of cells, did not differ noticeably from that of the ferritin standard. After 5-fluorouracil administration, which could also induce an oxidative-stress in cells, the absorption edge position was shifted toward higher energies representing a higher oxidation state of Fe. Intense treatment with antimycin A, which inhibits electron transfer in the respiratory chain, resulted in minor changes in the spectrum, resembling rather the N-donor Fe-{alpha},{alpha}'-dipyridyl complex at the oxidation energy of Fe(III), than ferritin. The incorporation of Co and Ni in the cells was followed by SR-TXRF measurements.

  16. Investigation by laser induced breakdown spectroscopy, X-ray fluorescence and X-ray powder diffraction of the chemical composition of white clay ceramic tiles from Veliki Preslav

    Energy Technology Data Exchange (ETDEWEB)

    Blagoev, K., E-mail: kblagoev@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Grozeva, M., E-mail: margo@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Malcheva, G., E-mail: bobcheva@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Neykova, S., E-mail: sevdalinaneikova@abv.bg [National Institute of Archaeology with Museum, Bulgarian Academy of Sciences, 2 Saborna, 1000 Sofia (Bulgaria)

    2013-01-01

    The paper presents the results of the application of laser induced breakdown spectroscopy, X-ray fluorescence spectrometry, and X-ray powder diffraction in assessing the chemical and phase composition of white clay decorative ceramic tiles from the medieval archaeological site of Veliki Preslav, a Bulgarian capital in the period 893–972 AC, well-known for its original ceramic production. Numerous white clay ceramic tiles with highly varied decoration, produced for wall decoration of city's churches and palaces, were found during the archaeological excavations in the old capital. The examination of fourteen ceramic tiles discovered in one of the city's monasteries is aimed at characterization of the chemical profile of the white-clay decorative ceramics produced in Veliki Preslav. Combining different methods and comparing the obtained results provides complementary information regarding the white-clay ceramic production in Veliki Preslav and complete chemical characterization of the examined artefacts. - Highlights: ► LIBS, XRF and XRD analyses of medieval white-clay ceramic tiles fragments are done. ► Different elements and phases, presented in the ceramics fragments were determined. ► Differences in the tiles' raw material mineral composition are found. ► Information of the tiles' production process and the raw clay deposits is obtained.

  17. Time-resolved X-ray diffraction at monocrystalline indium antimonide; Zeitaufgeloeste Roentgenbeugung an einkristallinem Indiumantimonid

    Energy Technology Data Exchange (ETDEWEB)

    Hoefer, Sebastian

    2014-11-07

    The present work deals with the experimental study of the structural change of the semiconductor indium antimonide (InSb) after excitation by an ultrashort laser pulse (60 fs). The investigation is carried out by ultra-short X-ray pulses (around 100 fs). As a source for ultrashort X-ray pulses serves a laser plasma X-ray source. With this source, a more intense ultrashort optical laser pulse is focused onto a metal foil (intensity to 8.10{sup 16} W/cm{sup 2}), and by the resulting plasma, there is an emission of X-rays. To characterize the X-ray source a novel Timepix detector was used, which made it possible to detect Bremsstrahlung up to photon energies of 700 keV. The penetration depth of X-rays is usually several micrometers and is thus much greater than the penetration depth of 100 nm of the laser pulse used for excitation. By the use of a highly asymmetric Bragg reflex the penetration depth of X-rays could be adapted to the penetration depth of the excitation pulse. Due to the low penetration depth of 2 ps after excitation an expansion of 4% of a 4 nm thin layer at the surface can already be measured. The excitation of the semiconductor will be described with different models theoretically, the temporal evolution of the deformation obtained therefrom is compared with the performed measurements. [German] Die vorliegende Arbeit behandelt die experimentelle Untersuchung der strukturellen Aenderung des Halbleiters Indiumantimonid (InSB) nach der Anregung durch einen ultrakurzen Laserpuls (60 fs). Die Untersuchung erfolgt durch ultrakurze Roentgenpulse (rund 100 fs). Als Quelle der ultrakurzen Roentgenpulse dient eine Laser-Plasma Roentgenquelle. Bei dieser Quelle wird ein ultrakurzer intensiver optischer Laserpuls auf eine Metallfolie fokussiert (Intensitaet bis 8.10{sup 16} W/cm{sup 2}), durch das entstehende Plasma kommt es zu einer Emission von Roentgenstrahlung. Zur Charakterisierung der Roentgenquelle stand ein neuartiger Timepix- Detektor zu Verfuegung, der

  18. Soft X-ray Laser Microscopy of Lipid Rafts towards GPCR-Based Drug Discovery Using Time-Resolved FRET Spectroscopy

    Directory of Open Access Journals (Sweden)

    Tatsuhiko Kodama

    2011-03-01

    Full Text Available Many signaling molecules involved in G protein-mediated signal transduction, which are present in the lipid rafts and believed to be controlled spatially and temporally, influence the potency and efficacy of neurotransmitter receptors and transporters. This has focus interest on lipid rafts and the notion that these microdomains acts as a kind of signaling platform and thus have an important role in the expression of membrane receptor-mediated signal transduction, cancer, immune responses, neurotransmission, viral infections and various other phenomena due to specific and efficient signaling according to extracellular stimuli. However, the real structure of lipid rafts has not been observed so far due to its small size and a lack of sufficiently sophisticated observation systems. A soft X-ray microscope using a coherent soft X-ray laser in the water window region (2.3–4.4 nm should prove to be a most powerful tool to observe the dynamic structure of lipid rafts of several tens of nanometers in size in living cells. We have developed for the X-ray microscope a new compact soft X-ray laser using strongly induced plasma high harmonic resonance. We have also developed a time-resolved highly sensitive fluorescence resonance energy transfer (FRET system and confirmed protein-protein interactions coupled with ligands. The simultaneous use of these new tools for observation of localization of G-protein coupled receptors (GPCRs in rafts has become an important and optimum tool system to analyze the dynamics of signal transduction through rafts as signaling platform. New technology to visualize rafts is expected to lead to the understanding of those dynamics and innovative development of drug discovery that targets GPCRs localized in lipid rafts.

  19. Fast and Furious: Shock heated gas as the origin of spatially resolved hard X-ray emission in the central 5 kpc of the galaxy merger NGC 6240

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Junfeng; Nardini, Emanuele; Fabbiano, Giuseppina; Karovska, Margarita; Elvis, Martin; Risaliti, Guido; Zezas, Andreas [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Pellegrini, Silvia [Dipartimento di Astronomia, Universitá di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Max, Claire [Center for Adaptive Optics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); U, Vivian, E-mail: jfwang@northwestern.edu [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2014-01-20

    We have obtained a deep, subarcsecond resolution X-ray image of the nuclear region of the luminous galaxy merger NGC 6240 with Chandra, which resolves the X-ray emission from the pair of active nuclei and the diffuse hot gas in great detail. We detect extended hard X-ray emission from kT ∼ 6 keV (∼70 MK) hot gas over a spatial scale of 5 kpc, indicating the presence of fast shocks with a velocity of ∼2200 km s{sup –1}. For the first time, we obtain the spatial distribution of this highly ionized gas emitting Fe XXV, which shows a remarkable correspondence to the large-scale morphology of H{sub 2}(1-0) S(1) line emission and Hα filaments. Propagation of fast shocks originating in the starburst-driven wind into the ambient dense gas can account for this morphological correspondence. With an observed L {sub 0.5-8} {sub keV} = 5.3 × 10{sup 41} erg s{sup –1}, the diffuse hard X-ray emission is ∼100 times more luminous than that observed in the classic starburst galaxy M82. Assuming a filling factor of 1% for the 70 MK temperature gas, we estimate its total mass (M {sub hot} = 1.8 × 10{sup 8} M {sub ☉}) and thermal energy (E {sub th} = 6.5 × 10{sup 57} erg). The total iron mass in the highly ionized plasma is M {sub Fe} = 4.6 × 10{sup 5} M {sub ☉}. Both the energetics and the iron mass in the hot gas are consistent with the expected injection from the supernovae explosion during the starburst that is commensurate with its high star formation rate. No evidence for fluorescent Fe I emission is found in the CO filament connecting the two nuclei.

  20. X-ray nanoprobes and diffraction-limited storage rings: opportunities and challenges of fluorescence tomography of biological specimens.

    Science.gov (United States)

    de Jonge, Martin D; Ryan, Christopher G; Jacobsen, Chris J

    2014-09-01

    X-ray nanoprobes require coherent illumination to achieve optic-limited resolution, and so will benefit directly from diffraction-limited storage rings. Here, the example of high-resolution X-ray fluorescence tomography is focused on as one of the most voracious demanders of coherent photons, since the detected signal is only a small fraction of the incident flux. Alternative schemes are considered for beam delivery, sample scanning and detectors. One must consider as well the steps before and after the X-ray experiment: sample preparation and examination conditions, and analysis complexity due to minimum dose requirements and self-absorption. By understanding the requirements and opportunities for nanoscale fluorescence tomography, one gains insight into the R&D challenges in optics and instrumentation needed to fully exploit the source advances that diffraction-limited storage rings offer.

  1. Time resolved X-ray Dark-Field Tomography Revealing Water Transport in a Fresh Cement Sample.

    Science.gov (United States)

    Prade, Friedrich; Fischer, Kai; Heinz, Detlef; Meyer, Pascal; Mohr, Jürgen; Pfeiffer, Franz

    2016-06-30

    Grating-based X-ray dark-field tomography is a promising technique for biomedical and materials research. Even if the resolution of conventional X-ray tomography does not suffice to resolve relevant structures, the dark-field signal provides valuable information about the sub-pixel microstructural properties of the sample. Here, we report on the potential of X-ray dark-field imaging to be used for time-resolved three-dimensional studies. By repeating consecutive tomography scans on a fresh cement sample, we were able to study the hardening dynamics of the cement paste in three dimensions over time. The hardening of the cement was accompanied by a strong decrease in the dark-field signal pointing to microstructural changes within the cement paste. Furthermore our results hint at the transport of water from certain limestone grains, which were embedded in the sample, to the cement paste during the process of hardening. This is indicated by an increasing scattering signal which was observed for two of the six tested limestone grains. Electron microscopy images revealed a distinct porous structure only for those two grains which supports the following interpretation of our results. When the water filled pores of the limestone grains empty during the experiment the scattering signal of the grains increases.

  2. Time resolved X-ray Dark-Field Tomography Revealing Water Transport in a Fresh Cement Sample

    Science.gov (United States)

    Prade, Friedrich; Fischer, Kai; Heinz, Detlef; Meyer, Pascal; Mohr, Jürgen; Pfeiffer, Franz

    2016-06-01

    Grating-based X-ray dark-field tomography is a promising technique for biomedical and materials research. Even if the resolution of conventional X-ray tomography does not suffice to resolve relevant structures, the dark-field signal provides valuable information about the sub-pixel microstructural properties of the sample. Here, we report on the potential of X-ray dark-field imaging to be used for time-resolved three-dimensional studies. By repeating consecutive tomography scans on a fresh cement sample, we were able to study the hardening dynamics of the cement paste in three dimensions over time. The hardening of the cement was accompanied by a strong decrease in the dark-field signal pointing to microstructural changes within the cement paste. Furthermore our results hint at the transport of water from certain limestone grains, which were embedded in the sample, to the cement paste during the process of hardening. This is indicated by an increasing scattering signal which was observed for two of the six tested limestone grains. Electron microscopy images revealed a distinct porous structure only for those two grains which supports the following interpretation of our results. When the water filled pores of the limestone grains empty during the experiment the scattering signal of the grains increases.

  3. Design of Time-Resolved Shifted Dual Transmission Grating Spectrometer for the X-Ray Spectrum Diagnostics

    Science.gov (United States)

    Wang, Baoqing; Yi, Tao; Wang, Chuanke; Zhu, Xiaoli; Li, Tingshuai; Li, Jin; Liu, Shenye; Jiang, Shaoen; Ding, Yongkun

    2016-07-01

    A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which has two sub transmission gratings with different line densities, of 2000 lines/mm and 5000 lines/mm. The axes of the two sub transmission gratings in SDTG are horizontally and vertically shifted a certain distance to measure a broad range of 0.1-5 keV time-resolved X-ray spectra. The SDTG has been calibrated with a soft X-ray beam of the synchrotron radiation facility and its diffraction efficiency is also measured. The designed SDTGS can take full use of the space on a record panel and improve the precision for measuring spatial and temporal spectrum simultaneously. It will be a promising application for accurate diagnosis of the soft X-ray spectrum in inertial confinement fusion. supported by National Natural Science Foundation of China (Nos. 11405158 and 11435011) and Development Foundation of China Academy of Engineering Physics (Nos. 2014B0102011 and 2014B0102012)

  4. Semiconductor applications of nanoliter droplet methodology with total reflection x-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Thomasin C.; Sparks, Christopher M.; Havrilla, George J. E-mail: havrilla@lanl.gov; Beebe, Meredith R

    2004-08-31

    In this study, the nanoliter dried spot method was applied to semiconductor contamination analysis to enhance vapor phase decomposition processes with total reflection X-ray fluorescence detection. Nanoliter-sized droplets (10 and 50 nl) were deposited onto native silicon oxide wafer surfaces in a clean room environment from both single and multielemental standards containing various concentrations of iron in different matrices. Direct comparisons were made to droplets formed by conventional VPD with similar iron standards. Nanoliter dried spots could be reproducibly deposited and dried in air with typical drying times ranging from 20 s to 2 min depending on the nanoliter volume deposited, compared to VPD spots which have drying times ranging from tens of minutes to several hours. Both types of residues showed a linear relationship between Fe intensity and mass deposited. Variable angle experiments showed that both nanoliter and VPD deposits of single element standards were film-like in character, while residues formed from much more complex matrices and higher mass loadings were particulate in character. For the experimental conditions used in this study (30 kV, 100 mA), typical TXRF spectral Fe limits of detection were calculated to be on the order of picograms or {approx}1x10{sup 10} atoms/cm{sup 2} for a 0.8 cm{sup 2} X-ray excitation beam area for both nanoliter dried spots and VPD spots prepared from single elemental standards. Calculated Fe detection limits for 200 mm diameter silicon wafers used in this study were in the {approx}1x10{sup 8} atoms/cm{sup 2} range. By using nanoliter sized droplets, the required sample volume is greatly reduced resulting in higher sample throughput than with conventional VPD methods.

  5. Rapid and reliable diagnosis of Wilson disease using X-ray fluorescence.

    Science.gov (United States)

    Kaščáková, Slávka; Kewish, Cameron M; Rouzière, Stéphan; Schmitt, Françoise; Sobesky, Rodolphe; Poupon, Joël; Sandt, Christophe; Francou, Bruno; Somogyi, Andrea; Samuel, Didier; Jacquemin, Emmanuel; Dubart-Kupperschmitt, Anne; Nguyen, Tuan Huy; Bazin, Dominique; Duclos-Vallée, Jean-Charles; Guettier, Catherine; Le Naour, François

    2016-07-01

    Wilson's disease (WD) is a rare autosomal recessive disease due to mutations of the gene encoding the copper-transporter ATP7B. The diagnosis is hampered by the variability of symptoms induced by copper accumulation, the inconstancy of the pathognomonic signs and the absence of a reliable diagnostic test. We investigated the diagnostic potential of X-ray fluorescence (XRF) that allows quantitative analysis of multiple elements. Studies were performed on animal models using Wistar rats (n = 10) and Long Evans Cinnamon (LEC) rats (n = 11), and on human samples including normal livers (n = 10), alcohol cirrhosis (n = 8), haemochromatosis (n = 10), cholestasis (n = 6) and WD (n = 22). XRF experiments were first performed using synchrotron radiation to address the elemental composition at the cellular level. High-resolution mapping of tissue sections allowed measurement of the intensity and the distribution of copper, iron and zinc while preserving the morphology. Investigations were further conducted using a laboratory X-ray source for irradiating whole pieces of tissue. The sensitivity of XRF was highlighted by the discrimination of LEC rats from wild type even under a regimen using copper deficient food. XRF on whole formalin-fixed paraffin embedded needle biopsies allowed profiling of the elements in a few minutes. The intensity of copper related to iron and zinc significantly discriminated WD from other genetic or chronic liver diseases with 97.6% specificity and 100% sensitivity. This study established a definite diagnosis of Wilson's disease based on XRF. This rapid and versatile method can be easily implemented in a clinical setting.

  6. Portable x-ray fluorescence for the analysis of chromium in nail and nail clippings.

    Science.gov (United States)

    Fleming, David E B; Ware, Chris S

    2017-03-01

    Assessment of chromium content in human nail or nail clippings could serve as an effective biomarker of chromium status. The feasibility of a new portable x-ray fluorescence (XRF) approach to chromium measurement was investigated through analysis of nail and nail clipping phantoms. Five measurements of 180s (real time) duration were first performed on six whole nail phantoms having chromium concentrations of 0, 2, 5, 10, 15, and 20µg/g. Using nail clippers, these phantoms were then converted to nail clippings, and assembled into different mass groups of 20, 40, 60, 80, and 100mg for additional measurements. The amplitude of the chromium Kα characteristic x-ray energy peak was examined as a function of phantom concentration for all measurement conditions to create a series of calibration lines. The minimum detection limit (MDL) for chromium was also calculated for each case. The chromium MDL determined from the whole nail intact phantoms was 0.88±0.03µg/g. For the clipping phantoms, the MDL ranged from 1.2 to 3.3µg/g, depending on the mass group analyzed. For the 40mg clipping group, the MDL was 1.2±0.1µg/g, and higher mass collections did not improve upon this result. This MDL is comparable to chromium concentration levels seen in various studies involving human nail clippings. Further improvements to the portable XRF technique would be required to detect chromium levels expected from the lower end of a typical population.

  7. Determination of trace element levels in leaves of Nerium oleander using X-Ray Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ramon S.; Sanches, Francis A.C.R.A.; Neves, Arthur O.P.; Oliveira, Luis F.; Oliveira, Davi F.; Anjos, Marcelino J. [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica Armando Dias Tavares. Dept. de Fisica Aplicada e Termodinamica

    2013-07-01

    The environmental pollution by human activity has been one of the most concerns in the last years, principally due to rapid urban growth in the cities and the industrialization process. The air pollution can be increased due to several different kinds of emissions: urban traffic, industrial activities, burning fuel, civil industry of construction/demolition, fires and natural phenomena. Many of these emissions move from long distances due to convections currents and finally tend to deposit mainly in the plants leaves and in the soil. Thus, the plants leaves works as a natural sampler by the emissions deposit in these ones. In this study Nerium oleander leaves were used to measure the environmental pollutions levels in different sampling urban regions in the city of Rio de Janeiro/RJ: Andarai, Benfica, Bonsucesso, Caju, Engenho de Dentro, Engenho Novo, Estacio, Grajau, Inhauma, Lins, Maracana, Maria da Graca, Meier, Praca da Bandeira, Riachuelo, Rio Comprido, Sao Cristovao, Tijuca, Vila Isabel and city Center. The control samples were collected in Campo Grande near of Parque Nacional da Pedra Branca/RJ (National Park of Pedra Branca/RJ). The leaves were collected from adult plants and after the collection the samples were cleaned and placed in the greenhouse for drying, then were mashed and pressed into tablets forms. The analyses were performed using the energy dispersion X-ray fluorescence (EDXRF), developed on the own laboratory and based in a SiPIN detector and a mini X ray tube. It was possible to detect 16 elements in the analyzed samples: K, Ca, Cr, Mn, Fe, Cu, Zn, Br, Rb, Sr, Ba and Pb. The results shows that, in the studied areas, the analysis of the Nerium oleander plant shows a low-cost option and with a substantial efficiency as an environmental pollution biomonitor. (author)

  8. High energy x-ray diffraction/x-ray fluorescence spectroscopy for high-throughput analysis of composition spread thin films.

    Science.gov (United States)

    Gregoire, John M; Dale, Darren; Kazimirov, Alexander; DiSalvo, Francis J; van Dover, R Bruce

    2009-12-01

    High-throughput crystallography is an important tool in materials research, particularly for the rapid assessment of structure-property relationships. We present a technique for simultaneous acquisition of diffraction images and fluorescence spectra on a continuous composition spread thin film using a 60 keV x-ray source. Subsequent noninteractive data processing provides maps of the diffraction profiles, thin film fiber texture, and composition. Even for highly textured films, our diffraction technique provides detection of diffraction from each family of Bragg reflections, which affords direct comparison of the measured profiles with powder patterns of known phases. These techniques are important for high throughput combinatorial studies as they provide structure and composition maps which may be correlated with performance trends within an inorganic library.

  9. Quantitative X-ray fluorescence analysis of samples of less than 'infinite thickness': Difficulties and possibilities

    Energy Technology Data Exchange (ETDEWEB)

    Sitko, Rafal, E-mail: rafal.sitko@us.edu.p [Institute of Chemistry, Silesian University, 40-006 Katowice (Poland)

    2009-11-15

    X-ray fluorescence spectrometry due to its nondestructive nature is widely applied in analysis of single layers and multiple layer films (e.g. semiconductors, electrooptic and solar cell devices, coatings, corrosion and paint layers), individual particles (airborne, fly ash, gunshot residue particles, etc.), art and archeological objects (manuscripts, paintings, icons) and many others. Quantitative analysis of these materials, frequently classified as samples of less than infinite thickness (thin or intermediate-thickness samples), required applying adequate matrix correction methods taking into account complex dependence of analyte fluorescent radiation intensity on full matrix composition and sample thickness. In this article, the matrix correction methods including fundamental parameters, Monte Carlo simulations, influence coefficients algorithms and methods based on X-ray transmission measurements are reviewed. The difficulties in the analysis of single layer and multiple layer films and the accuracy of fundamental parameter methods in simultaneous determination of their thickness and composition are discussed. The quantitative analysis of individual particles and inhomogeneous and/or complex structure materials using fundamental parameter and Monte Carlo simulation methods in micro-beam X-ray fluorescence spectrometry are also reviewed. Some references are devoted to the analysis of light matrix samples, e.g. geological, environmental and biological samples, in which undetectable low-Z elements are present (so-called 'dark matrix') using backscattered fundamental parameter methods. Since the samples of less than infinite thickness are partially transparent for X-ray beams, the transmission measurements present possibilities that are unattainable for bulk samples. Thus, the emission-transmission method and also new instruments allowing measurements of the primary X-ray beam transmitted through the sample together with measurements of X-ray

  10. Transient X-ray pulsar V0332+53: pulse phase-resolved spectroscopy and the reflection model

    CERN Document Server

    Lutovinov, A A; Suleimanov, V F; Mushtukov, A A; Doroshenko, V; Nagirner, D I; Poutanen, J

    2015-01-01

    We present the results of the pulse phase- and luminosity-resolved spectroscopy of the transient X-ray pulsar V0332+53, performed for the first time in a wide luminosity range (1-40)x10^{37} erg/s during a giant outburst observed by the RXTE observatory in Dec 2004 - Feb 2005. We characterize the spectra quantitatively and built the detailed "three-dimensional" picture of spectral variations with pulse phase and throughout the outburst. We show that all spectral parameters are strongly variable with the pulse phase, and the pattern of this variability significantly changes with luminosity directly reflecting the associated changes in the structure of emission regions and their beam patterns. Obtained results are qualitatively discussed in terms of the recently developed reflection model for the formation of cyclotron lines in the spectra of X-ray pulsars.

  11. Single-State Electronic Structure Measurements Using Time-Resolved X-Ray Laser Induced Photoelectron Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A J; Dunn, J; van Buuren, T; Hunter, J

    2004-11-11

    We demonstrate single-shot x-ray laser induced time-of-flight photoelectron spectroscopy on semiconductor and metal surfaces with picosecond time resolution. The LLNL COMET compact tabletop x-ray laser source provides the necessary high photon flux (>10{sup 12}/pulse), monochromaticity, picosecond pulse duration, and coherence for probing ultrafast changes in the city, chemical and electronic structure of these materials. Static valence band and shallow core-level photoemission spectra are presented for ambient temperature Ge(100) and polycrystalline Cu foils. Surface contamination was removed by UV ozone cleaning prior to analysis. In addition, the ultrafast nature of this technique lends itself to true single-state measurements of shocked and heated materials. Time-resolved electron time-of-flight photoemission results for ultra-thin Cu will be presented.

  12. On the emitting region of X-ray fluorescent lines around Compton-thick AGN

    CERN Document Server

    Liu, Jiren

    2016-01-01

    X-ray fluorescent lines are unique features of the reflection spectrum of the torus when irradiated by the central AGN. Their intrinsic line width can be used to probe the line-emitting region. Previous studies have focused on the Fe Ka line at 6.4 keV, which is the most prominent fluorescent line. These studies, however, are limited by the spectral resolution of currently available instruments, the best of which is $\\sim1860$ km s$^{-1}$ afforded by the Chandra High-Energy Grating (HEG). The HEG spectral resolution is improved by a factor of 4 at 1.74 keV, where the Si Ka line is located. We measured the FWHM of the Si Ka line for Circinus, Mrk 3, and NGC 1068, which are $570\\pm240$, $730\\pm320$, and $320\\pm280$ km s$^{-1}$, respectively. They are $3-5$ times smaller than those measured with the Fe Ka line previously. It shows that the intrinsic widths of the Fe Ka line are most likely to be over-estimated. The measured widths of the Si Ka line put the line-emitting region outside the dust sublimation radius...

  13. Field-induced alignment of a smectic-A phase: a time-resolved x-ray diffraction investigation.

    Science.gov (United States)

    Bras, W; Emsley, J W; Levine, Y K; Luckhurst, G R; Seddon, J M; Timimi, B A

    2004-09-01

    The field-induced alignment of a smectic-A phase is, in principle, a complicated process involving the director rotation via the interaction with the field and the layer rotation via the molecular interactions. Time-resolved nuclear magnetic resonance spectroscopy has revealed this complexity in the case of the director alignment, but provides no direct information on the motion of the layers. Here we describe a time-resolved x-ray diffraction experiment using synchrotron radiation to solve the challenging problem of capturing the diffraction pattern on a time scale which is fast in comparison with that for the alignment of the smectic layers. We have investigated the alignment of the smectic-A phase of 4-octyl-4(')-cyanobiphenyl by a magnetic field. The experiment consists of creating a monodomain sample of the smectic-A phase by slow cooling from the nematic phase in a magnetic field with a flux density of 7 T. The sample is then turned quickly through an angle phi(0) about an axis parallel to the x-ray beam direction but orthogonal to the field. A sequence of two-dimensional small angle x-ray diffraction patterns are then collected at short time intervals. Experiments were carried out for different values of phi(0), and at different temperatures. The results show that the alignment behavior changes fundamentally when phi(0) exceeds 45 degrees, and that there is a sharp change in the alignment process when the temperature is less than 3 degrees C below the smectic-A-nematic transition. The results of the x-ray experiments are in broad agreement with the NMR results, but reveal major phenomena concerning the maintenance of the integrity of the smectic-A layer structure during the alignment process. (c) 2004 American Institute of Physics

  14. Subnanosecond time-resolved x-ray measurements using an organic-inorganic perovskite scintillator

    Science.gov (United States)

    Kishimoto, S.; Shibuya, K.; Nishikido, F.; Koshimizu, M.; Haruki, R.; Yoda, Y.

    2008-12-01

    We have developed a fast x-ray detector using an organic-inorganic perovskite scintillator of phenethylamine lead bromide (PhE-PbBr4). The scintillator had a dominant light emission with a fast decay time of 9.9 ns. An x-ray detector equipped with a 0.9-mm-thick PhE-PbBr4 crystal was used to detect nuclear resonant scattering in N61i (the first excited level: 67.41 keV; lifetime: 7.6 ns) by using synchrotron radiation. With this detector, we could successfully record the decaying gamma rays emitted from N61i with a time resolution of 0.7 ns (full width at half maximum) and a relatively high detection efficiency of 24%.

  15. X-ray Fluorescence Tomography of Aged Fluid-Catalytic-Cracking Catalyst Particles Reveals Insight into Metal Deposition Processes

    NARCIS (Netherlands)

    Kalirai, Samanbir; Boesenberg, Ulrike; Falkenberg, Gerald; Meirer, Florian; Weckhuysen, Bert M.

    2015-01-01

    Microprobe X-ray fluorescence tomography was used to investigate metal poison deposition in individual, intact and industrially deactivated fluid catalytic cracking (FCC) particles at two differing catalytic life-stages. 3D multi-element imaging, at submicron resolution was achieved by using a large

  16. Analytical Instrument of X-ray Fluorescence Determine Concentration of U and Pu in Organic Solution at the Same Time

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An instrument is developed to measure the concentration of U, Pu and the intensity of gamma ray in samples of 1AP organic phase at the same time. The Ag cold cathode is used to excite L series X-ray fluorescence of U and Pu. The Si-pin detector is

  17. X-ray fluorescence spectrometry applied to soil analysis; Espectrometria de fluorescencia de raios X aplicada as analises de solo

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, Vera Lucia Ribeiro; Sato, Ivone Mulako; Scapin Junior, Wilson Santo; Scapin, Marcos Antonio; Imakima, Kengo [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). E-mail: vsalvado@baitaca.ipen.br; imsato@net.ipen.br; kengo@sup.ipen.br

    1997-07-01

    This paper studies the X-ray fluorescence spectrometry applied to the soil analysis. A comparative study of the WD-XRFS and ED-XRFS techniques was carried out by using the following soil samples: SL-1, SOIL-7 and marine sediment SD-M-2/TM, from IAEA, and clay, JG-1a from Geological Survey of Japan (GSJ)

  18. X-ray Fluorescence Tomography of Aged Fluid-Catalytic-Cracking Catalyst Particles Reveals Insight into Metal Deposition Processes

    NARCIS (Netherlands)

    Kalirai, Samanbir; Boesenberg, Ulrike; Falkenberg, Gerald; Meirer, Florian; Weckhuysen, Bert M.

    2015-01-01

    Microprobe X-ray fluorescence tomography was used to investigate metal poison deposition in individual, intact and industrially deactivated fluid catalytic cracking (FCC) particles at two differing catalytic life-stages. 3D multi-element imaging, at submicron resolution was achieved by using a

  19. Development of off-line layer chromatographic and total reflection X-ray fluorescence spectrometric methods for arsenic speciation

    Energy Technology Data Exchange (ETDEWEB)

    Mihucz, Victor G. [Joint Research Group of Environmental Chemistry of Hungarian Academy of Sciences and L. Eoetvoes University, P. O. Box 32, H-1518 Budapest (Hungary); Hungarian Satellite Centre of Trace Elements Institute to UNESCO, P. O. Box 32, H-1518 Budapest (Hungary); Moricz, Agnes M. [L. Eoetvoes University, Department of Chemical Technology and Environmental Chemistry, P.O. Box 32, H-1518 Budapest (Hungary); Kroepfl, Krisztina [Joint Research Group of Environmental Chemistry of Hungarian Academy of Sciences and L. Eoetvoes University, P. O. Box 32, H-1518 Budapest (Hungary); Szikora, Szilvia [Joint Research Group of Environmental Chemistry of Hungarian Academy of Sciences and L. Eoetvoes University, P. O. Box 32, H-1518 Budapest (Hungary); Tatar, Eniko [Hungarian Satellite Centre of Trace Elements Institute to UNESCO, P. O. Box 32, H-1518 Budapest (Hungary); L. Eoetvoes University, Department of Inorganic and Analytical Chemistry, P.O. Box 32, H-1518 Budapest (Hungary); Parra, Lue Meru Marco [Universidad Centro-occidental Lisandro Alvarado, Decanato de Agronomia, Departamento de Quimica y Suelos Unidad de Analisis Instrumental, Apartado Postal 4076, Cabudare 3023 (Venezuela); Zaray, Gyula [Joint Research Group of Environmental Chemistry of Hungarian Academy of Sciences and L. Eoetvoes University, P. O. Box 32, H-1518 Budapest (Hungary) and Hungarian Satellite Centre of Trace Elements Institute to UNESCO, P. O. Box 32, H-1518 Budapest (Hungary) and L. Eoetvoes University, Department of Inorganic and Analytical Chemistry, P.O. Box 32, H-1518 Budapest (Hungary)]. E-mail: zaray@ludens.elte.hu

    2006-11-15

    Rapid and low cost off-line thin layer chromatography-total reflection X-ray fluorescence spectrometry and overpressured thin layer chromatography-total reflection X-ray fluorescence spectrometry methods have been developed for separation of 25 ng of each As(III), As(V), monomethyl arsonic acid and dimethylarsinic acid applying a PEI cellulose stationary phase on plastic sheets and a mixture of acetone/acetic acid/water = 2:1:1 (v/v/v) as eluent system. The type of eluent systems, the amounts (25-1000 ng) of As species applied to PEI cellulose plates, injection volume, development distance, and flow rate (in case of overpressured thin layer chromatography) were taken into consideration for the development of the chromatographic separation. Moreover, a microdigestion method employing nitric acid for the As spots containing PEI cellulose scratched from the developed plates divided into segments was developed for the subsequent total reflection X-ray fluorescence spectrometry analysis. The method was applied for analysis of root extracts of cucumber plants grown in As(III) containing modified Hoagland nutrient solution. Both As(III) and As(V) were detected by applying the proposed thin layer chromatography/overpressured thin layer chromatography-total reflection X-ray fluorescence spectrometry methods.

  20. Development of Standard Samples for on-board Calibration of a New Planetary X-Ray Fluorescence Spectrometer

    Science.gov (United States)

    Dreißigacker, Anne; Köhler, Eberhard; Fabel, Oliver; van Gasselt, Stephan

    2014-05-01

    At the Planetary Sciences and Remote Sensing research group at Freie Universität Berlin an SCD-based X-Ray Fluorescence Spectrometer is being developed to be employed on planetary orbiters to conduct direct, passive energy-dispersive x-ray fluorescence measurements of planetary surfaces through measuring the emitted X-Ray fluorescence induced by solar x-rays and high energy particles. Because the Sun is a highly variable radiation source, the intensity of solar X-Ray radiation has to be monitored constantly to allow for comparison and signal calibration of X-Ray radiation from lunar surface materials. Measurements are obtained by indirectly monitoring incident solar x-rays emitted from a calibration sample. This has the additional advantage of minimizing the risk of detector overload and damage during extreme solar events such as high-energy solar flares and particle storms as only the sample targets receive the higher radiation load directly (while the monitor is never directly pointing towards the Sun). Quantitative data are being obtained and can be subsequently analysed through synchronous measurement of fluorescence of the Moon's surface by the XRF-S main instrument and the emitted x-ray fluorescence of calibration samples by the XRF-S-ISM (Indirect Solar Monitor). We are currently developing requirements for 3 sample tiles for onboard correction and calibration of XRF-S, each with an area of 3-9 cm2 and a maximum weight of 45 g. This includes development of design concepts, determination of techniques for sample manufacturing, manufacturing and testing of prototypes and statistical analysis of measurement characteristics and quantification of error sources for the advanced prototypes and final samples. Apart from using natural rock samples as calibration sample, we are currently investigating techniques for sample manufacturing including laser sintering of rock-glass on metals, SiO2-stabilized mineral-powders, or artificial volcanic glass. High precision

  1. Resolving the hard X-ray emission of GX 5-1 with INTEGRAL

    DEFF Research Database (Denmark)

    Paizis, A.; Ebisawa, K.; Tikkanen, T.;

    2005-01-01

    We present the study of one year of INTEGRAL data on the neutron star low mass X-ray binary GX 5-1. Thanks to the excellent angular resolution and sensitivity of INTEGRAL, we are able to obtain a high quality spectrum of GX 5-1 from similar to 5keV to similar to 100 keV, for the first time without...

  2. Chandra Phase-Resolved X-ray Spectroscopy of the Crab Pulsar II

    Science.gov (United States)

    Weisskopf, Martin C.; Tennant, Allyn F.; Yakovlev, Dimitry G.; Harding, Alice; Zavlin, Vyacheslav E.; Elsner, Ronald F.; Becker, Werner

    2012-01-01

    We present a new study of the X-ray spectral properties of the Crab Pulsar. The superb angular resolution of the Chandra X-ray Observatory enables distinguishing the pulsar from the surrounding nebulosity. Analysis of the spectrum as a function of pulse phase allows the least-biased measure of interstellar X-ray extinction due primarily to photoelectric absorption and secondarily to scattering by dust grains in the direction of the Crab Nebula. We modify previous findings that the line-of-sight to the Crab is under-abundant in oxygen and provide measurements with improved accuracy and less bias. Using the abundances and cross sections from Wilms, Allen & McCray (2000) we find [O/H] = (5.28+\\-0.28) x 10(exp -4) (4.9 x 10(exp -4) is solar abundance). \\rVe also measure for the first time the impact of scattering of flux out of the image by interstellar grains. \\rYe find T(sub scat) = 0.147+/-0.043. Analysis of the spectrum as a function of pulse phase also measures the X-ray spectral index even at pulse minimum - albeit with increasing statistical uncertainty. The spectral variations are, by and large, consistent with a sinusoidal variation. The only significant variation from the sinusoid occurs over the same phase range as some rather abrupt behavior in the optical polarization magnitude and position angle. We compare these spectral variations to those observed in Gamma-rays and conclude that our measurements are both a challenge and a guide to future modeling and will thus eventually help us understand pair cascade processes in pulsar magnetospheres. The data were also used to set new. and less biased, upper limits to the surface temperature of the neutron star for different models of the neutron star atmosphere.

  3. X-ray Fluorescence Observations of the Moon by SMART-1/D-CIXS

    Science.gov (United States)

    Grande, Manuel; Swinyard, B.; Joy, K. H.; Kellett, Barry J.; Crawford, Ian A.; Howe, Chris J.

    2008-09-01

    Introduction The SMART-1 mission to the Moon included in its payload D-CIXS, a compact X-ray spectrometer [1], [2] SMART-1 was a technology evaluation mission, and D-CIXS was the first of a new generation of planetary X-ray spectrometers. Novel technologies enabled new capabilities for measuring the fluorescent yield of a planetary surface or atmosphere which is illuminated by solar X-rays. During the extended SMART-1 cruise phase, observations of the Earth showed strong argon emission, providing a good source for calibration and demonstrating the potential of the technique. At the Moon, observations showed a first unambiguous remote sensing of calcium in the lunar regolith (Grande et al 2007) (Fig 1). Data obtained were broadly consistent with current understanding of mare and highland composition. Ground truth was provided by the returned Apollo and Luna sample sets. We have extended our observations to comparisons of Lunar near and farside, and by careful analysis enabled new elemental lines to be observed. Observations: In March, 2005, the SMART-1 spacecraft reached its nominal lunar orbit, and we began full commissioning for lunar operations. During the pre-commissioning period in mid-January, 2005, observations of the lunar surface were made which coincided with the occurrence of several major M and X class flares. This opportunity provided an excellent chance to observe spatially localized fluorescence from the lunar surface. X-ray fluorescent elemental lines from the lunar surface are detected by all three facets of D-CIXS while the XSM instrument observes the input solar spectrum. At the end of this interval, a long duration M-class solar flare began at 06:00 UTC on the 15th of January, 2005. The flare lasted for more than 1 hour but only ~30 minutes corresponded to D-CIXS observations. At this time SMART-1 was orbiting over the Moon's near-side eastern limb from about the equator, traveling northwards. As SMART-1 flew north, its altitude was also

  4. X-ray fluorescence for quantification of lead and strontium in vivo

    Science.gov (United States)

    Specht, Aaron James

    Lead (Pb) is a toxicant well known for its effects on almost every organ system in the body. Pb use in industry has declined since removal of Pb from gasoline, but many developing countries still have significant use of Pb. Exposure to Pb has been linked with diseases causing neurodegeneration and thus have lasting effects long after the initial exposure. Another metal, strontium (Sr), has been linked with bone disease in particular situations and shown to have uses in treating osteoporosis as a supplement. However, there are no studies of the effects of Sr using a meaningful biomarker. The most commonly used biomarkers for Pb and Sr exposures are blood Pb and Sr; however, blood tests are unable to identify long-term exposure levels due to the short half-life of these metals in blood. Bone stores of Pb and Sr have a half-life of years to decades and serve as a biomarker of long-term exposure. X-ray fluorescence has been used to measure bone Pb and Sr. However, current systems have limitations with radioisotope sources, bulky equipment, and long measurement times. A portable XRF device capable of measurement of bone Pb and Sr, overcomes the limitation of the current systems and has been developed in this work. The detection limit of the portable XRF for bone Pb and Sr was found to be 11 ppm and 5 ppm respectively at 5 mm of skin thickness. The portable XRF will have limitations of measurement based on an individual's skin thickness. The device was calibrated using standard phantoms and validated with in-lab samples, which demonstrated good agreement between KXRF and portable XRF measurements with strong correlations between goat bone, cadaver bone, and phantom measurements. In a population study of Pb poisoned children the portable XRF was further validated and a significant correlation between KXRF measured bone Pb and portable XRF measured bone Pb was identified; however, the device had limitations based on anatomical differences unaccounted for in children from

  5. In-vivo analysis of the uptake process of heavy metals through maize roots by using synchrotron X-ray fluorescence spectroscopy

    Science.gov (United States)

    Hwang, Bae Geun; Lee, Sang Joon; Gil, Kyehwan

    2016-12-01

    The uptake of heavy metals by plants has been receiving much attention for crop contamination and phytoremediation. We employed synchrotron X-ray fluorescence (XRF) spectroscopy for an in-vivo analysis of heavy-metal uptake through a strand of maize root. A focused X-ray beam of 2.5 × 2.5 μm2 in physical dimensions was scanned along horizontal lines of the maize root at intervals of 3 μm at the 4B X-ray micro-diffraction beamline of the Pohang Accelerator Laboratory (PAL). Time-resolved mapping of the fluorescence intensities from multiple metallic elements in the root tissues provided information about the radial distributions of heavy-metal elements and their temporal variations. The concentrated core stream of heavy-metal elements spread radially up to roughly 500 μm, corresponding to 40 % of the root diameter. The absorption characteristics of three heavy metals, Cr, Mn and Ni, and their physiological features were analyzed. The absolute concentrations and the contents of the heavy-metal elements in the tested maize roots were quantitatively evaluated by using the calibration curve obtained from reference samples with preset concentrations. The uptake quantities of the tested heavy-metal elements are noticeably different, although their molecular weights are similar. This study should be helpful for understanding plant physiology related with heavy-metal uptake.

  6. Synchrotron Radiation Total Reflection X-ray Fluorescence Spectroscopy for Microcontamination Analysis on Silicon Wafer Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Takaura, Norikatsu

    1997-10-01

    As dimensions in state-of-the-art CMOS devices shrink to less than 0.1 pm, even low levels of impurities on wafer surfaces can cause device degradation. Conventionally, metal contamination on wafer surfaces is measured using Total Reflection X-Ray Fluorescence Spectroscopy (TXRF). However, commercially available TXRF systems do not have the necessary sensitivity for measuring the lower levels of contamination required to develop new CMOS technologies. In an attempt to improve the sensitivity of TXRF, this research investigates Synchrotron Radiation TXRF (SR TXRF). The advantages of SR TXRF over conventional TXRF are higher incident photon flux, energy tunability, and linear polarization. We made use of these advantages to develop an optimized SR TXRF system at the Stanford Synchrotron Radiation Laboratory (SSRL). The results of measurements show that the Minimum Detection Limits (MDLs) of SR TXRF for 3-d transition metals are typically at a level-of 3x10{sup 8} atoms/cm{sup 2}, which is better than conventional TXRF by about a factor of 20. However, to use our SR TXRF system for practical applications, it was necessary to modify a commercially available Si (Li) detector which generates parasitic fluorescence signals. With the modified detector, we could achieve true MDLs of 3x10{sup 8} atoms/cm{sup 2} for 3-d transition metals. In addition, the analysis of Al on Si wafers is described. Al analysis is difficult because strong Si signals overlap the Al signals. In this work, the Si signals are greatly reduced by tuning the incident beam energy below the Si K edge. The results of our measurements show that the sensitivity for Al is limited by x-ray Raman scattering. Furthermore, we show the results of theoretical modeling of SR TXRF backgrounds consisting of the bremsstrahlung generated by photoelectrons, Compton scattering, and Raman scattering. To model these backgrounds, we extended conventional theoretical models by taking into account several aspects particular

  7. Probing the graphite band structure with resonant soft-x-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Carlisle, J.A.; Shirley, E.L.; Hudson, E.A. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Soft x-ray fluorescence (SXF) spectroscopy using synchrotron radiation offers several advantages over surface sensitive spectroscopies for probing the electronic structure of complex multi-elemental materials. Due to the long mean free path of photons in solids ({approximately}1000 {angstrom}), SXF is a bulk-sensitive probe. Also, since core levels are involved in absorption and emission, SXF is both element- and angular-momentum-selective. SXF measures the local partial density of states (DOS) projected onto each constituent element of the material. The chief limitation of SXF has been the low fluorescence yield for photon emission, particularly for light elements. However, third generation light sources, such as the Advanced Light Source (ALS), offer the high brightness that makes high-resolution SXF experiments practical. In the following the authors utilize this high brightness to demonstrate the capability of SXF to probe the band structure of a polycrystalline sample. In SXF, a valence emission spectrum results from transitions from valence band states to the core hole produced by the incident photons. In the non-resonant energy regime, the excitation energy is far above the core binding energy, and the absorption and emission events are uncoupled. The fluorescence spectrum resembles emission spectra acquired using energetic electrons, and is insensitive to the incident photon`s energy. In the resonant excitation energy regime, core electrons are excited by photons to unoccupied states just above the Fermi level (EF). The absorption and emission events are coupled, and this coupling manifests itself in several ways, depending in part on the localization of the empty electronic states in the material. Here the authors report spectral measurements from highly oriented pyrolytic graphite.

  8. Total reflection X-ray fluorescence trace mercury determination by trapping complexation: Application in advanced oxidation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Custo, Graciela [Unidad de Actividad Quimica, Comision Nacional de Energia Atomica, Av. Gral Paz 1499 (B1650KNA) San Martin, Buenos Aires (Argentina); Litter, Marta I. [Unidad de Actividad Quimica, Comision Nacional de Energia Atomica, Av. Gral Paz 1499 (B1650KNA) San Martin, Buenos Aires (Argentina); Escuela de Posgrado, Universidad de General San Martin, San Lorenzo 3391 Villa Ballester, 1653. Prov. de Buenos Aires (Argentina); Rodriguez, Diana [Universidad Nacional de Lujan, Ruta 5 y 7. Prov. de Buenos Aires (Argentina); Vazquez, Cristina [Unidad de Actividad Quimica, Comision Nacional de Energia Atomica, Av. Gral Paz 1499 (B1650KNA) San Martin, Buenos Aires (Argentina) and Laboratorio de Quimica de Sistemas Heterogeneos, Facultad de Ingenieria, Universidad de Buenos Aires, P. Colon 850 (C1063ACU), Buenos Aires (Argentina)]. E-mail: Cristina.Vazquez@cnea.gov.ar

    2006-11-15

    It is well known that Hg species cause high noxious effects on the health of living organisms even at very low levels (5 {mu}g/L). Quantification of this element is an analytical challenge due to the peculiar physicochemical properties of all Hg species. The regulation of the maximal allowable Hg concentration led to search for sensitive methods for its determination. Total reflection X-ray fluorescence is a proved instrumental analytical tool for the determination of trace elements. In this work, the use of total reflection X-ray fluorescence for Hg quantification is investigated. However, experimental determination by total reflection X-ray fluorescence requires depositing a small volume of sample on the reflector and evaporation of the solvent until dryness to form a thin film. Because of volatilization of several Hg forms, a procedure to capture these volatile species in liquid samples by using complexing agents is proposed. Acetate, oxalic acid, ethylenediaminetetracetic acid and ammonium pyrrolidine-dithiocarbamate were assayed for trapping the analytes into the solution during the preparation of the sample and onto the reflector during total reflection X-ray fluorescence measurements. The proposed method was applied to evaluate Hg concentration during TiO{sub 2}-heterogeneous photocatalysis, one of the most known advanced oxidation technologies. Advanced oxidation technologies are processes for the treatment of effluents in waters and air that involve the generation of very active oxidative and reductive species. In heterogeneous photocatalysis, Hg is transformed to several species under ultraviolet illumination in the presence of titanium dioxide. Total reflection X-ray fluorescence was demonstrated to be applicable in following the extent of the heterogeneous photocatalysis reaction by determining non-transformed Hg in the remaining solution.

  9. Total reflection X-ray fluorescence trace mercury determination by trapping complexation: Application in advanced oxidation technologies

    Science.gov (United States)

    Custo, Graciela; Litter, Marta I.; Rodríguez, Diana; Vázquez, Cristina

    2006-11-01

    It is well known that Hg species cause high noxious effects on the health of living organisms even at very low levels (5 μg/L). Quantification of this element is an analytical challenge due to the peculiar physicochemical properties of all Hg species. The regulation of the maximal allowable Hg concentration led to search for sensitive methods for its determination. Total reflection X-ray fluorescence is a proved instrumental analytical tool for the determination of trace elements. In this work, the use of total reflection X-ray fluorescence for Hg quantification is investigated. However, experimental determination by total reflection X-ra