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Sample records for 3d-micro x-ray fluorescence

  1. Methodology toward 3D micro X-ray fluorescence imaging using an energy dispersive charge-coupled device detector.

    Garrevoet, Jan; Vekemans, Bart; Tack, Pieter; De Samber, Björn; Schmitz, Sylvia; Brenker, Frank E; Falkenberg, Gerald; Vincze, Laszlo

    2014-12-01

    A new three-dimensional (3D) micro X-ray fluorescence (μXRF) methodology based on a novel 2D energy dispersive CCD detector has been developed and evaluated at the P06 beamline of the Petra-III storage ring (DESY) in Hamburg, Germany. This method is based on the illumination of the investigated sample cross-section by a horizontally focused beam (vertical sheet beam) while fluorescent X-rays are detected perpendicularly to the sheet beam by a 2D energy dispersive (ED) CCD detector allowing the collection of 2D cross-sectional elemental images of a certain depth within the sample, limited only by signal self-absorption effects. 3D elemental information is obtained by a linear scan of the sample in the horizontal direction across the vertically oriented sheet beam and combining the detected cross-sectional images into a 3D elemental distribution data set. Results of the 3D μXRF analysis of mineral inclusions in natural deep Earth diamonds are presented to illustrate this new methodology. PMID:25346101

  2. Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation

    Schmitz, Susanne; Möller, Andreas; Wilke, Max;

    2009-01-01

    A confocal set-up for three-dimensional (3D) micro X-ray fluorescence (micro-XRF) was used at the mySpot beamline at BESSY II, which allows compositional depth profiling for various applications. We present results obtained with a confocal 3D micro-XRF set-up for chemical age dating using the U, Th...... and Pb concentrations of monazite within rock thin sections. The probing volume was determined to be approximately 21 × 21 × 24 µm3 for W-La using an excitation energy of 19 keV. The relative detection limits particularly for Pb are below 10 ppm (for counting times of 1000 s). Therefore, this 3D micro-XRF...... ages, varying from 20 Ma to 1.82 Ga. Reference materials (GM3, F6, 3345) can be reproduced within error. The spread in the ages of all points determined by 3D micro-XRF is within 8 % of the isotopic reference value. The average 3D micro-XRF dates reproduce the reference ages with discrepancies between...

  3. X-ray Fluorescence Sectioning

    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...

  4. X-ray fluorescence holography

    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)

  5. X-ray fluorescence spectrometry

    The seventh edition of Philips' Review of Literature on x-ray fluorescence spectrometry starts with a list of conference proceedings on the subject, organised by the Philips organisation at regular intervals in various European countries. It is followed by a list of bulletins. The bibliography is subdivided according to spectra, equipment, applications and absorption analysis

  6. Detection limits in x-ray fluorescence analysis

    X-ray fluorescence spectrometry is a well established analytical technique for elemental analysis of solids, powders, or liquids. This extended abstract briefly discusses the detection limits or sensitivity of x-ray spectrometers in x-ray fluorescence analysis

  7. Simulation of x-ray fluorescence spectra

    A method for simulating x-ray fluorescence (XRF) spectra in hybrid densitometry is presented. This technique allows simulation of XRF spectra for solutions with arbitrary concentrations of special nuclear material and minor actinides excited by an x-ray generator. Spectra for mixed uranium and plutonium solutions with U/Pu ratios ranging from 100 to 1 have been generated. This range of ratios applies to most solutions found in plutonium reprocessing plants. XRF simulation can provide important data for estimating instrument precision, evaluating analysis techniques, and training system operators. Applications of XRF simulation in the development of the Los Alamos Hybrid K-Edge/XRF Densitometer system are described

  8. Development of confocal micro X-ray fluorescence instrument using two X-ray beams

    A new confocal micro X-ray fluorescence instrument was developed. This instrument has two independent micro X-ray tubes with Mo targets. A full polycapillary X-ray lens was attached to each X-ray tube. Another half polycapillary lens was attached to a silicon drift X-ray detector (SDD). The focal spots of the three lenses were adjusted to a common position. The effects of the excitation of two X-ray beams were investigated. The instrument enabled highly sensitive three-dimensional X-ray fluorescence analysis. We confirmed that the X-ray fluorescence intensity from the sample increased by applying the two independent X-ray tubes in confocal configuration. Elemental depth profiling of black wheat was demonstrated with the result that each element in the surface coat of a wheat grain showed unique distribution

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

    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.

  10. Surface-Enhanced X-Ray Fluorescence

    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.

  11. Silicon lithium detector for x ray fluorescence

    The Silicon Lithium detector is the system for the detection of nuclear radiation. It transforms the charge that was produced inside of Silicon material as a result of the incidence of particles and X rays, in voltage pulses at the output of the preamplifier. In this work was made the adjustment of the technological process of manufacture of the detector. Also was made the design and construction of the cryostat and preamplifier and then the validation of the system in a Cuban Dewar. The system, which was made for the first time in our country, has an energy resolution of 185 eV for the Fe-55 source (E=5.9 KeV), which has permitted its implementation in energy dispersive X ray fluorescence. (author)

  12. Total reflection X-ray fluorescence analysis

    In the past few years, total reflection X-ray flourescence analysis (TXRF) has found an increasing number of assignments and applications. Experience of trace element analysis using TXRF and examples of applications are already widespread. Therefore, users of TXRF had the opportunity of an intensive exchange of their experience at the 1st workshop on total reflection X-ray fluorescence analysis which took place on May 27th and 28th 1986 at the GKSS Research Centre at Geesthacht. In a series of lectures and discussions dealing with the analytical principle itself, sample preparation techniques and applications as well as comuter programs for spectrum evaluation, the present state of development and the range of applications were outlined. 3 studies out of a total of 14 were included separately in the INIS and ENERGY databases. With 61 figs., 12 tabs

  13. In vivo X-ray fluorescence analysis

    Measurements on five occupationally exposed persons have shown that it is possible to use X-ray fluorescence analysis for in vivo measurements of lead in the skeleton. The technique for calibrating in vivo X-ray fluorescence measurements of lead in bone tissue has been studied in detail and a two-component phantom simulating the bone and the soft tissue parts of the finger constructed. The technique has been used for in vivo measurements on 22 occupationally exposed persons. The minimum detectable concentration of lead in fingerbones was found to be around 20 μg x g-1. The lead concentrations in their skeletons and blood were compared: the correlation was poor. The variations in lead concentrations in the skeleton have been studied in occupationally exposed persons and in samples from archaeological skeletons. The sensitivity and the minimum detectable concentration of cadmium in the kidney cortex in in vivo measurements has been studied by measurements on kidney models. The minimum detectable concentration was 20 μg x g-1 at a skin-kidney distance of 30 mm and 40 μg x g-1 at 40 mm. Five persons occupationally exposed were studied. (Author)

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

    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.

  15. Fluorescence X-ray micro-spectroscopy activities at ESRF

    Salome, M; Bleuet, P; Chalmin, E; Cloetens, P; Andrade, V De; Martinez-Criado, G; Petitgirard, S; Rak, M; Tresserras, J A Sans; Tucoulou, R; Susini, J [European Synchrotron Radiation Facility, X-ray Imaging Group, BP 220, F-38043 Grenoble Cedex (France); Bohic, S [INSERM U-836, Institut des Neurosciences Grenoble, Universite Joseph Fourier UMR-S 836, F-38042 Grenoble (France); Cauzid, J [CREGU and UMR G2R 7566, Universite Poincare, BP 23, F-54506 Vandoeuvre-Les-Nancy Cedex (France); Cotte, M [Centre de Recherche et de Restauration des Musees de France, CNRS-UMR 171, Palais du Louvre, 14, quai Francois Mitterrand, F-7501 Paris (France); Szlachetko, J, E-mail: salome@esrf.f [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland)

    2009-09-01

    The X-ray Microscopy and Micro-analysis beamlines at ESRF operate complementary state-of-the-art instruments at ID21, ID22, ID18F and more recently ID22NI. Within a multi-modal strategy, these beamlines develop micro-imaging techniques with various contrast mechanisms ({mu}XRF, {mu}XANES, {mu}XRD and phase contrast) and host experiments with scientific topics ranging from Geochemistry to Archeology, Environmental sciences, Biology and Material sciences. Future challenges include pushing spatial resolution down to the nano-scale and the development of innovative 3D micro-analysis techniques.

  16. X-ray fluorescence micro-tomography and laminography using an x-ray scanning microscope

    Watanabe, N; Hoshino, M; Yamamoto, K; Aoki, S [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Takeuchi, A; Suzuki, Y, E-mail: watanabe@bk.tsukuba.ac.j [SPring-8, JASRI, Mikazuki, Hyogo 679-5198 (Japan)

    2009-09-01

    Using a scanning microscope with a zone plate, x-ray fluorescence micro-tomography was investigated at SPring-8 BL20XU. A 120 nm-thick zinc layer could be resolved in the reconstructed section image. A frozen phytoplankton and a iron impurity of a diamond could be also reconstructed. X-ray fluorescence laminography was tested at SPring-8 BL47XU. A tantalum line pattern of 3 {mu}m line width could be reconstructed.

  17. X-ray fluorescence micro-tomography and laminography using an x-ray scanning microscope

    Using a scanning microscope with a zone plate, x-ray fluorescence micro-tomography was investigated at SPring-8 BL20XU. A 120 nm-thick zinc layer could be resolved in the reconstructed section image. A frozen phytoplankton and a iron impurity of a diamond could be also reconstructed. X-ray fluorescence laminography was tested at SPring-8 BL47XU. A tantalum line pattern of 3 μm line width could be reconstructed.

  18. X-ray fluorescence micro-tomography and laminography using an x-ray scanning microscope

    Watanabe, N.; Hoshino, M.; Yamamoto, K.; Aoki, S.; Takeuchi, A.; Suzuki, Y.

    2009-09-01

    Using a scanning microscope with a zone plate, x-ray fluorescence micro-tomography was investigated at SPring-8 BL20XU. A 120 nm-thick zinc layer could be resolved in the reconstructed section image. A frozen phytoplankton and a iron impurity of a diamond could be also reconstructed. X-ray fluorescence laminography was tested at SPring-8 BL47XU. A tantalum line pattern of 3 μm line width could be reconstructed.

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

    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.

  20. Advanced of X-ray fluorescence logging technique in China

    The paper discuses principle of X-ray fluorescence logging, and introduces advanced of X-ray fluorescence logging technique in China. By 2009, third generation XRF logging instrument has been developed in China, and good logging result has been obtained in Lala copper mine. (authors)

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

    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.

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

    Lane, DW; 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...

  3. X-ray fluorescence in investigations of archaeological finds

    Cechak, T. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic); Hlozek, M. [Institute of Archaeology and Museology, Masaryk University, Arna Novaka 1, 602 00 Brno (Czech Republic); Musilek, L. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic)], E-mail: musilek@fjfi.cvut.cz; Trojek, T. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic)

    2007-10-15

    X-ray fluorescence can be successfully used for analysing the elemental composition of the superficial layers of a measured object, especially for investigating surface coatings, deposits of adventitious materials on the surface, etc. An energy dispersive version of X-ray fluorescence analysis is used in our investigations for analysing various historic objects, art works and archaeological finds. Examples of the application of X-ray fluorescence to various archaeological finds from excavations in the Czech Republic are presented - shards of ancient glazed ceramics, moulds for casting metal products, the remains of a human finger with traces of brass, probably from a ring, etc.

  4. X-ray fluorescence in investigations of archaeological finds

    X-ray fluorescence can be successfully used for analysing the elemental composition of the superficial layers of a measured object, especially for investigating surface coatings, deposits of adventitious materials on the surface, etc. An energy dispersive version of X-ray fluorescence analysis is used in our investigations for analysing various historic objects, art works and archaeological finds. Examples of the application of X-ray fluorescence to various archaeological finds from excavations in the Czech Republic are presented - shards of ancient glazed ceramics, moulds for casting metal products, the remains of a human finger with traces of brass, probably from a ring, etc

  5. Research in quantitative microscopic X-ray fluorescence analysis

    A feasibility study of quantitative elemental microanalysis of biological materials and glass samples by microbeam X-ray fluorescence spectroscopy was completed. The research included testing the homogeneity of existing standards for X-ray fluorescence calibration and verification of a fundamental parameters method for quantitative analysis. The goal was to evaluate the X-ray fluorescence spectrometer as a tool for elemental analysis at the microscale level. Glass Standard Reference Materials were analyzed. The glass specimens consisted of flat, optically polished slabs having three different thicknesses. For calibration, metal thin films were used. The microbeam X-ray fluorescence spectrometer utilizing capillary optics with effective beam diameter equal to about 30 μm has been applied in this research. Sources of uncertainties considered in this work were detector and X-ray tube stability, specimen movement, and spectral deconvolution. Concentrations of analytes were calculated using a fundamental parameters approach. Coherently and incoherently scattered lines of tube target were used for matrix correction and to estimate the mass thickness of the sample. The synchrotron microbeam X-ray fluorescence technique was used for quantitative analysis of human brain tissue samples. In measurements the monochromatic and polychromatic synchrotron microbeams were applied. The same area of tissue sample was scanned with the use of both X-ray microbeams. The concentrations of selected elements were computed. A reasonably good agreement between results of both analyses was obtained

  6. X-ray fluorescence logging in molybdenum deposit exploration

    Described is the methods for X-ray fluorescence logging in molybdenum deposit exploration in South Kazakhstan. X-ray fluorescence logging was carried out with GKS-1N four-channel gamma spectrometer with SP-4 hole device containing clamping. 109Cd isotope of 10μCi activity was used as a source for excitation of characteristic radiation of molybdenum K-line (E=22 keV, T=470 days) and a proportional counter with the resolution of 12% along 125Sb (E=27 keV) line was used as a detector. Described are methods for interpretation of X-ray flUorescence logs using a nomogram for molybdenum determination in holes filled with water. The sensitivity threshold is 0.05% of molybdenum. Economic efficiency of deposit exploration with the help of holes and subsequent X-ray fluorescence logging is 2.8 mln roubles

  7. X-ray fluorescence analysis of uranium concentrates

    Uranium concentrates were analyzed by x-ray fluorescence for the following impurities: arsenic, calcium, iron, molybdenum, phosphorus, silicon, sulfur, thorium, and vanadium. All of the impurities except arsenic can be determined simultaneously

  8. System for Gamma an X rays fluorescence spectrometric

    A system for spectrometry of gamma or fluorescence X rays is presented. It sis composed by a Si(Li) semiconductors detector, a charge sensitive preamplifier, a high voltage power supply, a spectrometric amplifier and a monolithic 1024 channels multichannel analyzers or an IBM compatible 4096 channels add - on- card multichannel analyzer. The system can be configured as a 1024 or 4096 channels gamma or fluorescent X rays spectrometer

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

    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 DotTM 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 ∼ 0.04 ng and a mean particle diameter of ∼ 0.06 μm. 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

  10. X-ray fluorescence (XRF) set-up with a low power X-ray tube.

    Gupta, Sheenu; Deep, Kanan; Jain, Lalita; Ansari, M A; Mittal, Vijay Kumar; Mittal, Raj

    2010-10-01

    The X-ray fluorescence set-up with a 100 W X-ray tube comprises a computer controlled system developed for remote operation and monitoring of tube and an adjustable stable 3D arrangement to procure variable excitation energies with low scattered background. The system was tested at different filament currents/anode voltages. The MDL of the set-up at 0.05-1.00 mA/4-12 kV is found approximately (1-100)ppm for K and L excitations and approximately (200-700)ppm for M excitations of elements and improves with filament current and anode voltage. Moreover, L measurements for Sm and Eu at five K X-ray energies of elements(Z=29-40) and analytical determination in some synthetic samples were undertaken. PMID:20570160

  11. X-ray fluorescence (XRF) set-up with a low power X-ray tube

    Gupta, Sheenu; Deep, Kanan [Nuclear Science Laboratories, Physics Department, Punjabi University, Patiala 147 002 (India); Jain, Lalita; Ansari, M.A. [Laser Electronic Support Section, Raja Ramanna Centre for Advanced Technology (RRCAT), Indore (India); Mittal, Vijay Kumar [Nuclear Science Laboratories, Physics Department, Punjabi University, Patiala 147 002 (India); Mittal, Raj, E-mail: rmsingla@yahoo.co [Nuclear Science Laboratories, Physics Department, Punjabi University, Patiala 147 002 (India)

    2010-10-15

    The X-ray fluorescence set-up with a 100 W X-ray tube comprises a computer controlled system developed for remote operation and monitoring of tube and an adjustable stable 3D arrangement to procure variable excitation energies with low scattered background. The system was tested at different filament currents/anode voltages. The MDL of the set-up at 0.05-1.00 mA/4-12 kV is found {approx}(1-100) ppm for K and L excitations and {approx}(200-700) ppm for M excitations of elements and improves with filament current and anode voltage. Moreover, L measurements for Sm and Eu at five K X-ray energies of elements(Z=29-40) and analytical determination in some synthetic samples were undertaken.

  12. Investigation of total reflection X-ray fluorescence analysis technique

    Total-Reflection X-ray Fluorescence spectrometry (TRXF) is known for its high sensitivity down to Pg-level or sub ppb level, respectively. Therefore the spectrometry is considered as a most competitive tool in the application of trace element analysis. The technique of TRXF was investigated in the laboratory. But small isotope X-γ source is chosen as an exciting source instead of general X-ray tube. From the primitive experiment the conclusion proved that the condition of total reflection can be built and the analysis sensitivity of TRXF is higher than that of normal x-ray analysis

  13. Total-reflection x-ray fluorescence with a brillant undulator x-ray source

    Total-reflection x-ray fluorescence (TXRF) is a highly sensitive technique for analyzing trace elements, because of the very low background from the sample support. Use of third-generation synchrotron x-ray source could further enhance the detection power. However, while such high sensitivity permits the detection of signals from trace elements of interest, it also means that one can observe weak parasitic x-rays as well. If the sample surface becomes even slightly contaminated, owing to air particulates near the beamline, x-ray fluorescence lines of iron, zinc, copper, nickel, chromium, and titanium can be observed even for a blank sample. Another critical problem is the low-energy-side tail of the scattering x-rays, which ultimately restricts the detection capability of the technique using a TXRF spectrometer based on a Si(Li) detector. The present paper describes our experiments with brilliant undulator x-ray beams at BL39XU and BL40XU, at the SPring-8, Harima, Japan. The emphasis is on the development of instruments to analyze a droplet of 0.1 μl containing trace elements of ppb level. Although the beamline is not a clean room, we have employed equipment for preparing a clean sample and also for avoiding contamination during transferring the sample into the spectrometer. We will report on the successful detection of the peak from 0.8 ppb selenium in a droplet (absolute amount 80 fg). We will also present the results of recent experiments obtained from a Johansson spectrometer rather than a Si(Li) detector. (author)

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

    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.

  15. X-ray fluorescence in IAEA Member States: Peru

    Full text: Under the IAEA TC project PER/2/018 (1993-1994) on 'Nuclear Training' an EDXRF spectrometer based on Cd-109 radioisotope source was installed. Then in 1998 a Total Reflection X-ray Fluorescence module was attached under the project PER/9/020 on 'Analytical Nuclear Techniques for Environmental Control'. The XRF laboratory belongs to the Chemistry Department of Science Direction - General Direction for Promotion and Technical Development of the Peruvian Institute of Nuclear Energy and is located at the auxiliary laboratories of the Nuclear Centre. The following three thesis for degree in chemistry were completed: 1. 'Multielemental Analysis of archeological bones by X-ray Fluorescence for the reconstruction of diets at First Period in the Lima Culture'; 2. 'Determination of heavy metals in water of the Rimac river by Total Reflection X-Ray Fluorescence'; 3. 'Multielemental Analysis of sea water samples by Total Reflection X-Ray Fluorescence, using pre-concentration with APDC/MIBK' (in edition). Currently we are working on another thesis dealing with 'Multielemental analysis of biological marine samples by Total Reflection X-Ray Fluorescence and pre-concentration after microwave digestion'. In order to get the accreditation, we are working on validation of the analytical methods for determination of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Pb in natural water by using Total Reflection X-Ray Fluorescence technique. The EDXRF spectrometer with Cd-109 excitation is used for the analysis of clays, potteries, soil, sediments, geological materials, bones, etc., mainly for the archaeological applications. (author)

  16. X-ray fluorescence microtomography analyzing prostate tissues

    The objective of this work is to determine the elemental distribution map in reference samples and prostate tissue samples using X-Ray Fluorescence Microtomography (XRFCT) in order to verify concentrations of certain elements correlated with characteristics observed by the transmission microtomography. The experiments were performed at the X-Ray Fluorescence Facility of the Brazilian Synchrotron Light Laboratory. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The transmission CT images were reconstructed using filtered-back-projection algorithm, and the XRFCT images were reconstructed using filtered-back-projection algorithm with absorption corrections. (author)

  17. Research status of energy dispersive X-ray fluorescence spectrometer

    Background: Energy dispersive X-ray fluorescence spectrometer has been improved rapidly in these years. Purpose: Research status of energy dispersive X-ray fluorescence spectrometers is reviewed, covering the main components in the spectrometer and spectra processing algorithms. Methods: On the component aspect, the working principles and performances of high-voltage generator, X-ray excitation sources, especially X-ray tubes and detector are compared. On the spectra processing aspect, results of different algorithms in spectrum de-noising, background subtraction, decomposition of the peaks and calculating the intensity of the fluorescence are analyzed separately. Results: On the component aspect, the effects to sensitivity and resolution of the spectrometer being caused by the high-voltage of the voltage generator, intensity of X-ray and resolution of the detector are concluded. On the spectra processing aspect, feasibilities of various algorithms are suggested. The advantages of wavelet transform, artificial neural network and partial least-squares method are discussed. Conclusion: Present difficulties in further improving of the spectrometer performance are analyzed. The prospect and the necessity of further research of EDXRF have been suggested. (authors)

  18. X-ray-fluorescence measurement of thin film thicknesses

    A method and apparatus were developed for X-ray fluorescence measurement of the thicknesses of thin metal films deposited on top of each other on a substrate. The method is highly accurate and rapid and is especially useful for making microelectronic devices. The system involves exposing the metal films to X-ray radiation, then measuring the intensity of the various fluorescent lines excited by the radiation. The lead-detecting collimator has a conical bore and a very small entrance aperture used to define the surface area of the top film from which excited fluorescence is to be detected. The collimator has an opening in the side to allow some of the incident X-rays from the source to enter the bore to excite fluorescence in the lead. This fluorescence is monitored by a detector as a measure of the intensity of the incident X-rays. The system is first calibrated in a systematic way to specify a set of parameters characteristic of the plated-metal configuration to be measured. The sample is irradiated and the number of counts in each of the selector characteristic lines of the platings and substrate is measured. The thickness of the plating layers are then calculated by an iterative method in accordance with specified relationships between the calibrated parameters and the measured counts. (DN)

  19. X-ray fluorescence analysis major elements in silicate minerals

    Hagan, R.C.

    1982-09-01

    An automated wavelength-dispersive x-ray fluorescence spectrometer is operational for analysis of major elements in rocks and minerals. Procedures for trace-element analysis are being developed. Sample preparation methods and analytical techniques are similar to those commonly used elsewhere, but data reduction is conducted by the Fundamental Parameters program developed by Criss. Unlike empirically derived calibration curves, this data reduction method considers x-ray absorption and secondary fluorescence, which vary with differences in sample composition. X-ray intensities for each element from several standards are averaged to develop a theoretical standard for comparison with samples of unknown composition. Accurate data for samples with wide compositional ranges result from these data reduction and standardization techniques.

  20. Quantitative X ray analysis system. User's manual and guide to X ray fluorescence technique

    This guide covers trimmed and re-arranged version 3.6 of the Quantitative X ray Analysis System (QXAS) software package that includes the most frequently used methods of quantitative analysis. QXAS is a comprehensive quantitative analysis package that has been developed by the IAEA through research and technical contracts. Additional development has also been carried out in the IAEA Laboratories in Seibersdorf where QXAS was extensively tested. New in this version of the manual are the descriptions of the Voigt-profile peak fitting, the backscatter fundamental parameters' and emission-transmission methods of chemical composition analysis, an expanded chapter on the X ray fluorescence physics, and completely revised and increased number of practical examples of utilization of the QXAS software package. The analytical data accompanying this manual were collected in the IAEA Seibersdorf Laboratories in the years 2006/2007

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

    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.

  2. HIgh Rate X-ray Fluorescence Detector

    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

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

    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.

  4. USB apply to field X-ray fluorescence analysis

    This article analyzes the feasibility of application USB and GPS to field X-ray fluorescence analysis, and focuses on the hardware and firmware design of USB and multi-channel analyzer (MCA), then simply discusses the device driver design and the PC application software design. (authors)

  5. Characterization of monel alloys by X-ray fluorescence technique

    Method for the determination of Ni, Cu, Fe, Mn, Si, Al, Ti, Co, Cr and Mo in Monel alloys using thin film for sample preparation and X-ray fluorescence techniques is described. Samples in filings form were completely dissolved with inorganic acids and they were made up to a known volume. Then, these samples were deposited in a filter paper, reducing in this form the effect of the matrix. For all elements the first order emission Kα lines were selected for measurements and for excitation a rhodium X-ray tub was utilized. For the heavier elements the LiF (200). (author)

  6. Rapid analysis by X-ray fluorescence excitation

    The application of the energy dispersive X-ray fluorescence spectrometry for a quick multielement analysis of different samples (sedimented dust, motor oil, watery solutions) is discussed. Using a source of 30 mCi 239Pu for the X-ray excitation it is possible to determine the concentration of the elements Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr, and Pb in a single working operation with a detection efficiency between 1000 ppm for Ca and about 10 ppm for Zn, Br, Sr and Pb using a testing time of 1000 seconds. (author)

  7. Silver coins analyses by X-ray fluorescence methods.

    Torrisi, L; Italiano, A; Cutroneo, M; Gentile, C; Torrisi, A

    2013-01-01

    The investigation on the differences occurring in the manufacture of silver coins allows to get information on their elemental composition and represents a powerful support to the methodology to identify the producing technologies, workshops being also instrumental to distinguish between original and counterfeit ones. Aim of the present work is to study recent and old silver coins through non-destructive X-Ray Fluorescence (XRF) analysis. The XRF was applied to extend the analysis to the deepest layers of the coins; for surface layers an X-ray tube or an electron beam were employed to induce the atom fluorescence to obtain information on the surface elemental composition. Moreover, a detailed study has been performed to evaluate the influence of the surface curvature on the measurement, by deducing a proper corrective factor to keep into account in the data analysis. The elemental atomic composition was measured for each coin, mainly by means of the X-ray tube excitation for the bulk and the electron Scanning Electron Microscope (SEM) microbeam probe for the surface patina analysis. Ionization was induced by an X-ray tube using an Ag anode for the bulk and by an electron microprobe for the surface composition. X-ray detection was performed by using a semiconductor Si device cooled by a Peltier system. The Ag L-lines X-ray yield is affected by coin surface morphology and geometry. The comparison between coin spectra and standard samples, shows that the Ag quantitative analysis is influenced by error of the atomic concentration lower that 10%. PMID:24004868

  8. Effect of Electric Voltage and Current of X-ray Chamber on the Element inthe Zirconium Alloy Analysis X-ray by X-ray Fluorescence

    The using of x-ray fluorescence in the chemical analysis depend heavilyon the parameters of x-ray chamber, for examples : electric voltage andelectric current. That parameter give effect in the result of determine ofSn, Cr, Fe and Ni in the zirconium alloy. 20 kV electric voltages are used onthe Mo x-ray chamber shall product x-ray of zirconium in the sample materialcan give effect in the stability of the analysis result (deviation more than5%). The result of analysis of elements in the zirconium alloy shall givedeviation less than 5% when using of electric voltage of the x-ray chamberless than 19 kV. The sensitivity of analysis can be reached by step upelectric current of x-ray chamber. (author)

  9. High-spatial-resolution nanoparticle x-ray fluorescence tomography

    Larsson, Jakob C.; Vâgberg, William; Vogt, Carmen; Lundström, Ulf; Larsson, Daniel H.; Hertz, Hans M.

    2016-03-01

    X-ray fluorescence tomography (XFCT) has potential for high-resolution 3D molecular x-ray bio-imaging. In this technique the fluorescence signal from targeted nanoparticles (NPs) is measured, providing information about the spatial distribution and concentration of the NPs inside the object. However, present laboratory XFCT systems typically have limited spatial resolution (>1 mm) and suffer from long scan times and high radiation dose even at high NP concentrations, mainly due to low efficiency and poor signal-to-noise ratio. We have developed a laboratory XFCT system with high spatial resolution (sub-100 μm), low NP concentration and vastly decreased scan times and dose, opening up the possibilities for in-vivo small-animal imaging research. The system consists of a high-brightness liquid-metal-jet microfocus x-ray source, x-ray focusing optics and an energy-resolving photon-counting detector. By using the source's characteristic 24 keV line-emission together with carefully matched molybdenum nanoparticles the Compton background is greatly reduced, increasing the SNR. Each measurement provides information about the spatial distribution and concentration of the Mo nanoparticles. A filtered back-projection method is used to produce the final XFCT image.

  10. Proton-induced x-ray fluorescence CT imaging

    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

  11. Proton-induced x-ray fluorescence CT imaging

    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 mm2 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 (R2 > 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 small animal

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

    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.

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

    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

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

    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.

  15. Survey of realization possibilities in X-ray fluorescence analysis

    X-ray fluorescence analysis is reviewed as a method of quantitative chemical analysis. Physical basis of the method and the sample preparation process, having an important effect on the sensitivity and accuracy of the method, are briefly described. Different realization and equipment construction possibilities are discussed in detail, including the method of non-dispersive or differential filter pair which leads to the decrease of measuring time and statistical errors. (D.Gy)

  16. Analysis of silicate rocks by x-ray fluorescence spectrometry

    This study aims at developing an all-purpose method for the determination of various elements in silicate rocks, by means of X-ray fluorescence spectrometry. The sample is prepared by borax fusion, in the presence of cobalt oxide acting as an inner standard meant for eliminating certain errors. Contents are computed in comparison with outer standards having a chemical composition akin to that of the rock sample under analysis. (authors)

  17. In vivo X-ray fluorescence analysis for medical diagnosis

    A Monte Carlo code has been constructed and used to simulate the energy distribution of scattered photons abtained in various in vivo X-ray fluorescence measurements. The structure of this distribution has been investigated and discussed. Studies of the response function of the Ge-decector used have made it possible to convert the calculated scatter spectra to pulse-height distributions. These studies have shown to be valuabel tools in designing in vivo X-ray fluorescence measurements. In vivo X-ray fluorescence measurements have been used for quantitative non-invasive measurements of the concentration of iodine-containing contrast media in rabbits without the use of blood or urine sampling. The biological half-life of the contrast medium in the soft tissue part of the nose (measured in vivo) was similar to that in serum (measured in vitro) when determined in the period 2-4 hours after injection. This result indicate the possibility of being able to use the method for clinical evaluation of kidney function. The method has been used in patients referred for urography and who had teherefore been injected with routine amounts of iodinecontaining urographic contrast medium. After urography, the elimination rates of urographic contrast medium from both serum and finger tissue were determined and copared during a two-hour period which began two hours after injection of contrast medium. A strong degree of correlation was found between the elimination rates from serum and finger tissue and also between the total clearances calculated from the serum and finger measurements respectively. Thus, after radiographic examinations quantitative estimation of kidney function may be obtained as a fringe benefit by external X-ray fluorescence measurements of the elimination from tissue of the contrast medium used. (author)

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

    Groover, Krishangi; Izbicki, John

    2016-01-01

    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.

  19. Total Reflection X Ray Fluorescence: an approach to nano analysis

    Within the last decade, Total Reflection X Ray Fluorescence (TXRF) has become an extremely powerful method of element analysis. It allows nanoanalytical investigations in three different ways: (i) use of minute sample amounts of only some 100 nanograms, (i i) determination of extreme traces down to nanograms per liter and (i i i) depth profiling of near surface layers of only 10 nanometer thickness. The basic principles of TXRF are described and examples of applications are demonstrated

  20. Bone lead measured by X-ray fluorescence: epidemiologic methods.

    Hu, H; Aro, A; Rotnitzky, A

    1995-01-01

    In vivo X-ray fluorescence (XRF) measurement of bone lead concentration (XRF) has emerged as an important technique for future epidemiological studies of long-term toxicity. Several issues germane to epidemiologic methodology need to be addressed, however. First, sources of variability in measurements of bone lead need to be quantified, including imprecision related to the physical measurement itself and the variability of lead deposition over the two main compartments of bones (cortical vs. ...

  1. Portable x-ray fluorescence spectrometer for Works of art

    X-ray fluorescence is an analytical technique of prier importance in archaeometry, for restoration and art history investigation; it is because of non-destructive and multi-elemental character of the analysis simplicity and high speed of operation, ability to produce immediate analytical results for the objects, which can neither be sampled nor removed to the laboratory Recent advances in X-ray tubes, X-ray detectors and electronic provided an opportunity to produce portable high resolution XRF spectrometers characterized by a good reliability and analytical performance; in this paper a prototype portable XRF spectrometer based on a small size, low power X-ray tube and a thermometrically cooled Si-Pin detector is described. The spectrometer provides a possibility for direct and secondary target excitation geometry use of proper secondary target and filter and size adjustment of the primary photon bean by using a set of different beam collimators; the portable XRF spectrometer was successfully applied to study art objects in the Art History Museum in Vienna, including such objects as old master paintings bronze and brass alloys of antique as well as Renaissance objects and silver/copper coins produced at different locations. Quantitative and Quantitative analysis were amedee depending of the curator questions and discussed from the point of view of art History. The importance of the results for restoration and authentification of the art objects is also emphasized

  2. Applications of synchrotron x-ray fluorescence to extraterrestrial materials

    Sutton, S.R.; Rivers, M.L.; Smith, J.V.

    1986-01-01

    Synchrotron x-ray fluorescence (SXRF) is a valuable technique for trace element analyses of extraterrestrial materials permitting minimum detection limits less than 1 ppM for 20 micrometer spots. SXRF measurements have been performed on iron meteorites and micrometeorites using white synchrotron radiation and an energy dispersive x-ray detector at the National Synchrotron Light Source (X-26C), Brookhaven National Laboratory (NY). Partitioning of Cu between troilite (FeS) and metal in the nine iron meteorites studied suggests sub-solidus re-equilibration in these objects. A technique has been developed for determining self-absorption corrections for filtered, continuum excitation of small specimens, such as stratospheric particles and refractory inclusions in meteorites.

  3. Hybrid fluorescence tomography/x-ray tomography improves reconstruction quality

    Schulz, R. B.; Ale, A.; Sarantopoulos, A.; Freyer, M.; Söhngen, R.; Zientkowska, M.; Ntziachristos, V.

    2009-07-01

    A novel hybrid imaging system for simultaneous X-ray and Fluorescence Tomography is presented, capitalizing on 360°-projection free-space fluorescence tomography. The system is implemented within a commercial micro-CT scanner allowing reconstructions with a resolution of 95μm. Acquired data sets are intrinsically coregistered in the same coordinate system and can be used to correctly localize reconstructed fluorescence distributions with morphological features. More importantly, the micro-CT data, automatically segmented into different organ and tissue segments can be used to guide the fluorescence reconstruction algorithm and reduce the ill coditioning of the inverse problem. We showcase the use of the system and the improvements in image quality for lesions in brain and lung.

  4. X-ray scattering in X-ray fluorescence spectra with X-ray tube excitation - Modelling, experiment, and Monte-Carlo simulation

    Hodoroaba, V.-D., E-mail: Dan.Hodoroaba@bam.d [BAM Federal Institute for Materials Research and Testing, Division VI.4 Surface Technologies, D-12200 Berlin (Germany); Radtke, M. [BAM Federal Institute for Materials Research and Testing, Division I.3 Structure Analysis, Polymer Analysis, D-12200 Berlin (Germany); Vincze, L. [Ghent University, Department of Analytical Chemistry, B-9000 Ghent (Belgium); Rackwitz, V.; Reuter, D. [BAM Federal Institute for Materials Research and Testing, Division VI.4 Surface Technologies, D-12200 Berlin (Germany)

    2010-12-15

    X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses.

  5. X-ray scattering in X-ray fluorescence spectra with X-ray tube excitation - Modelling, experiment, and Monte-Carlo simulation

    X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses.

  6. Analysis of fresco paintings by X-ray fluorescence method

    In this work we present the application of X-ray fluorescence analysis (XRFA) to examine fresco paintings from the Karlstejn castle. The X-ray fluorescence apparatus built and operated in the Laboratory of Quantitative Methods in Research of Ancient Monuments was used for the purpose of fresco paintings measurements. The X-ray sources (radionuclides) generate the characteristic X-ray photons from the sample. The Si(Li) detector measures numbers and energies of photons emitted from the specimen. The energy and number of photons detected can be converted into kind and amount of measured atoms. These results give data for qualitative and quantitative analysis of samples. XRFA is relatively simple and non-destructive method. Capability of in-situ measurement is one of big advantages of this method. The radionuclide sources of exciting radiation (e.g. 55Fe enables the excitation of elements with Z up to 23, 238Pu is used in interval of Z from 20 to 39 etc.) were used. An Si(Li) semiconductor detector with a 5 l Dewar vessel and portable spectroscopy system enable the in situ measurement. Narrow collimation of the exciting beam makes it possible to select the measured area of fresco painting. The valuable fresco paintings from the Karlstejn castle were investigated in this way. The measurements were carried out in collaboration with the Analytical Laboratory of the State Institute for the Preservation of Historic Monuments. A suitable analysis of paintings makes it possible to detect the kind of colours and evaluate changes in the surface colour of paintings and suggest useful and timely procedures for their conservation and restoration. (author)

  7. X-ray fluorescence in IAEA Member States: Spain

    Full text: Instrumental facilities of the ICMUV include: a Total-reflection X-Ray Fluorescence (TXRF), laboratory and portable Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometers. These equipments are employed in the field of the art and archaeometry. Current projects are: EDXRF analysis of blue pigments used in Valencian ceramics. EDXRF analyses of cobalt-blue pigments were made on 73 pieces of Valencian ceramics from the beginning of the 14th century up to 20th century. These ceramic samples have the pigment decoration applied together with a tin opacified lead glaze cover on the clay body. The comparison between EDXRF spectra from coloured and non-coloured areas provides information about the pigment composition. The following elements: Mn, Fe, Co, Ni, Cu, Zn and As are identified as characteristics of the blue pigments. Different association of these elements as well as correlation with the chronology of the samples were found. These results can be used for identifying the different types of cobalt ores employed in the manufacture of the blue pigments to study their provenance. Non-destructive analysis of paper supports used in prints: In paper based works of art it is not possible to separate the support from the work of the author. Then, the maximum knowledge of the support in this kind of works is desirable. In this work, Energy Dispersive X-Ray Fluorescence (EDXRF) was used to determine the elemental composition of a set of European and Oriental papers from the 20th century and an Arabian paper from the 14th century. These papers were manufactured with different production techniques and used as support for writing, drawing and printing. Normalised fluorescence yields of the elements to the weight of the paper show that there are some correlations between its elemental composition and the type of paper, provenance and use. Therefore, the Energy Dispersive X-Ray Fluorescence (EDXRF) technique could be used for a better characterization and

  8. X-ray fluorescence in Member States: Slovenia. Applications of X ray fluorescence spectrometry in biology and food science

    Our objective here is to present briefly two applications of the XRF elemental analysis, which we recently started: applying the XRF analysis after sample excitation by radioisotope sources, X ray tubes in the standard and the total reflection modes (TXRF), as well as by PIXE and microPIXE. The fluorescence X ray spectra shown below are typical examples of data and information on basis of which all the applications were realized. It is obvious that the use of the techniques, which produce the above spectra require a good knowledge of the nuclear spectroscopy, and also skills to adjust the experimental set-up including the source of fluorescence excitation, selection of appropriate X ray detection system (geometry of experiment), as well as proper sampling and sample preparation, considering the characteristics of a large variety of different materials to be examined. And finally one needs to define the application and establish good collaboration with the users and/or scientists in a number of interesting fields. We would like to present here just two examples of such a comprehensive approach to the application of XRF analysis

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

    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 mm2, thickness = 3.5 mm, 175 eV (5.9 keV), 430 eV (59.6 keV); S = 100 mm2; thickness = 4.5 mm, 270 eV (5.9 keV), 485 eV (59,6 keV). (2) Si-planar detector: S = 10 mm2, thickness = 0.4 mm, 230 eV (5.9 keV), 460 eV (59.6 keV). (3) CdTe p-i-n detectors: S = 16 mm2, thickness 0.5 mm, 350 eV (5.9 keV), 585 eV (59.6 keV). S = 16 mm2, 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, criminalistics and history of art are demonstrated. (author)

  10. Analysis of industrial material with X ray fluorescence

    The content of selenium in a calcium carbonate based fodder additive was determined by X ray fluorescence (XRF) analysis using radionuclide excitation. The aim was to develop a fast and uncomplicated technique that could be used on-site, for example in a factory or in other places of industrial scale production of material. The selenium contents to be determined were around 4-5 mass per cent in the additive, which is produced in tonne quantities; hence emphasis was placed upon the mobility and simplicity of the device rather than upon the possibility of analysis of small traces

  11. Blood selenium content determination by X-ray fluorescence

    The presence of some elements in small amounts (traces) in the human body is of foremost importance for the prevention and treatment of several diseases. It has been recently shown that traces of selenium in blood are closely related to the occurrence of miotonic distrophy, a muscular disease that is affecting a significant percentage of the population. This work describes a simple procedure to determine selenium in human blood serum by energy dispersive X-ray fluorescence analysis. Final quantification is achieved through the addition of titanium as an internal standard. (Author)

  12. Rare earth aerosol analysis by x-ray fluorescence spectrometry

    An analytical method for the determination of four lanthanides in air filter samples is described. The method involves simultaneous quantitative determinations of La, Ce, Pr, and Nd at the microgram level by x-ray fluorescence spectrometry without chemical separation of these rare earths and without serious interferences from the dust matrices on the filters. The method has been used successfully to analyze some air filter samples collected at a rare earth processing refinery in Illinois. A description of the development of the method is given as well as the results obtained by using this method on the air filter samples. The reproducibility of the results was generally +-5%

  13. X-ray fluorescence analysis of welding fume particles

    A commercial standard filter set and two laboratory-made standard filter sets are compared via the analysis of generated welding fume samples by X-ray fluorescence. The latter standards are made by (1) hydrophobic-edge membrane filters spiked with prepared metal ion solutions, and (2) filters through which a dispersion of metal oxide powder in isopropanol has been drawn. The results are presented in table form. Precision (Pre) is the relative standard deviation of the six samples. Four main conclusions are enumerated

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

    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.

  15. Analysis of archaeological ceramics using x-ray fluorescence technique

    Radioisotope x-ray fluorescence method was applied to provenance studies of ceramics fragments originated from the Mar-Takla site in Syria. 35 samples were analyzed, where each sample was irradiated 1000 s by 109Cd radioisotope source and the elements (As, Ca, fe, Ga, Nb, Mn, Pb, Rb, Sr, Ti, Y, Zn, and Zr) were determined. The data were subjected to two multivariate statistical methods, cluster and principal component analysis (PCA). The study show that 94% of the samples can be considered to be manufactured using two sources of raw materials. (Author)

  16. Studies of some alloys using x-ray fluorescence

    In this project an attempt has been made for the study of alloys commonly used using x-ray fluorescence ( XRF ) technique. The alloys selected for the study included gold jewellery, steels, brasses and coins. The XRF method proved to be simple, fast, non-destructive and reliable as compared to chemical methods. The results showed that most of the gold jewellery used in this country have carat value of 18 and 21. Also most coins used in different countries are alloys of Cu and Ni. A simple spark method was used for the determination of C in steels, since C is not possible to analyze by XRF. ( Author )

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

    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...

  18. X-ray scattering in X-ray fluorescence spectra with X-ray monochromatic, polarised excitation - Modelling, experiment, and Monte-Carlo simulation

    Hodoroaba, V.-D., E-mail: Dan.Hodoroaba@bam.de [BAM Federal Institute for Materials Research and Testing, Division 6.4 Surface Technologies, D-12200 Berlin (Germany); Radtke, M.; Reinholz, U.; Riesemeier, H. [BAM Federal Institute for Materials Research and Testing, Division 1.3 Structure Analysis, Polymer Analysis, D-12200 Berlin (Germany); Vincze, L. [Ghent University, Department of Analytical Chemistry, B-9000 Ghent (Belgium); Reuter, D. [BAM Federal Institute for Materials Research and Testing, Division 6.4 Surface Technologies, D-12200 Berlin (Germany)

    2011-07-01

    A systematic series of measurements has been carried out with monochromatic X-ray excitation with synchrotron radiation in order to check a physical model on X-ray scattering. The model has recently been successfully tested for the case of polychromatic, unpolarised excitation emitted by an X-ray tube. Our main purpose is the modelling of a physical background in X-ray fluorescence spectra, so that improved quantitative results can be achieved especially for strongly scattering specimens. The model includes single Rayleigh and Compton scattering in the specimen, the effect of bound electrons, the challenging Compton broadening and the polarisation degree. Representative specimens, measurement geometries and excitation energies have been selected with synchrotron monochromatic light at BAMline/BESSY II. Monte-Carlo simulations have been also carried out in order to evaluate the quality of the results achieved with the model.

  19. X-ray scattering in X-ray fluorescence spectra with X-ray monochromatic, polarised excitation - Modelling, experiment, and Monte-Carlo simulation

    A systematic series of measurements has been carried out with monochromatic X-ray excitation with synchrotron radiation in order to check a physical model on X-ray scattering. The model has recently been successfully tested for the case of polychromatic, unpolarised excitation emitted by an X-ray tube. Our main purpose is the modelling of a physical background in X-ray fluorescence spectra, so that improved quantitative results can be achieved especially for strongly scattering specimens. The model includes single Rayleigh and Compton scattering in the specimen, the effect of bound electrons, the challenging Compton broadening and the polarisation degree. Representative specimens, measurement geometries and excitation energies have been selected with synchrotron monochromatic light at BAMline/BESSY II. Monte-Carlo simulations have been also carried out in order to evaluate the quality of the results achieved with the model.

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

    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...

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

    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,...

  2. X-ray fluorescence in Member States: Venezuela

    The direct analysis of biological samples is the main research challenge of the scientific group at the Unidad de Analisis Instrumental of the Agronomy Faculty, Universidad Centro Occidental Lisandro Alvarado, (UCLA) Edo. Lara, Venezuela. The technique of total reflection X-ray fluorescence (TXRF) plays an important role in the scientific activities of the laboratory. In this field, the research is devoted to the design, development, evaluation and application of methods for the analysis of biological and related samples, such as biological tissues, fluids, biota, soil and water samples. The studies involve the evaluation of feasibility for direct determination of analytes, the in situ (in quartz sample holder) preparation techniques, the in situ pre-concentration and speciation among others studies. The methods are developed for the application in clinical studies, agronomy, environmental monitoring, bioremediation, statistical processing of data and neural network applications. The following projects are described: Direct analysis of biological samples by TXRF; Determination of calcium, potassium, manganese, iron, cooper and zinc levels in representative samples of two onion cultivars using TXRF and ultrasound extraction procedure; Evaluation of vermicompost as bioadsorbent substrate of Pb, Ni, V and Cr for waste waters remediation using total reflection X-ray fluorescence; Determination by TXRF of total As in onion plants growing in contaminated substrates

  3. Plating thickness measurement using x-ray fluorescence

    Recently, there has been increased demand for the accurate thickness measurement of the plating on small electronic parts. This technology is required for both production and quality control. The coating thickness measurement using X-ray fluorescence is the standard method used because of its accuracy and versatility. Beta-ray backscattering method is also described. The operation of a beta-ray gauge is fairly simple, and the normal measuring time with it is much shorter than that of other methods. It is one of nondestructive methods, and excellent in view of its accuracy, ease of operation and speed. The engineers of Seiko Instruments and Electronics Ltd. have endeavored to eliminate the weak points of beta-ray backscattering while keeping the instrument as inexpensive as possible. The detection system of X-ray fluorescence (XRF) was complicated and expensive, but the recent development of low cost and compact electronic devices brought the cost of XRF instruments down, thus the widely spread use of XRF advances. The data shows the many advantages of XRF over beta-ray backscattering. The on-line XRF coating thickness gauges for reel to reel plating application are at the forefront of this technology. The use of solid state detectors for XRF gauges to expand the application and to increase energy resolution is a possibility. Any strong competition does not seem to develop against XRF. (Kako, I.)

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

    Chwiej, Joanna; Szczerbowska-Boruchowska, Magdalena; Lankosz, Marek; Wojcik, Slawomir; Falkenberg, Gerald; Stegowski, Zdzislaw; Setkowicz, Zuzanna

    2005-12-01

    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.

  5. A low power x-ray tube for use in energy dispersive x-ray fluorescence analysis

    A low power X-ray tube with thin molybdenum transmission target for use in energy dispersive X-ray fluorescence (ENDXRF) element analysis has been indigenously built, along with its power supply. The X-ray tube has been in operation since August 1979, and it has been operated upto maximum target voltage of 35 KV and tube current upto 200 μA which is more than sufficient for trace element analysis. This X-ray tube has been used alongwith the indigenously built Si(Li) detector X-ray spectrometer with an energy resolution of 200 eV at 5.9 Kev MnKsub(α) X-ray peak for ENDXRF analysis. A simple procedure of calibration has been developed for thin samples based on the cellulose diluted, thin multielement standard pellets. Analytical sensitivities of the order of a few p.p.m. have been obtained with the experimental setup for elements with 20 < = Z < = 38 and 60 < = Z < = 90. A number of X-ray spectra for samples of environmental, biological, agricultural, industrial and metallurgical interest are presented to demonstrate the salient features of the experimental sep up. (auth.)

  6. Applications of EGS4 Monte Carlo simulation for x-ray source characterization and potable x-ray fluorescence spectroscopy

    We applied EGS4 Monte Carlo (MC) simulation to the spectral evaluation of the primary x-ray beam from low-power x-ray tube and the prediction of the energy-dispersive x-ray fluorescence (ED-XRF) analysis of metals. The end-window type of small x-ray tube with Mo anode was adopted to observe the backscattered component of the primary x-ray beam under the condition of low power (<50 kV, <1 μA). For estimation of the filtration effect on the primary x-ray beam, the set of Si and Mo sheet optimized for harmful heavy elements analysis were used. On the other hand, the ED-XRF spectra of metals were recorded using a portable spectrometer with LiF bend monochromator which enables simple measurement situation. In all measurement situations MC calculations were done using low energy extension of EGS4 code, and the experimental data can be compared directly with the simulated spectrum. Results showed that the EGS4 MC calculations are useful method for spectral evaluation of x-ray tube and analysis of ED-XRF measurement. (author)

  7. X-ray fluorescence in Member States: United Arab Emirates. United Arab Emirates' National X ray Fluorescence Laboratory

    The United Arab Emirates (UAE) is currently experiencing an era of accelerated development and expansion in all aspects of civil activities. Huge industrial, as well as, construction projects, evident to the casual observer, have resulted in the creation of environmental conditions that need continuous monitoring. In addition to that, wide interest in the heritage and archaeological findings in the UAE, have necessitated the establishment of a national scientific laboratory capable of analyzing a variety of samples non-destructively, with high accuracy and a minimum amount of sample preparation. X ray fluorescence (XRF) is one of a number of methods that are suitable for the type of analysis required. XRF is widely used for chemical analysis, particularly in the investigation of metals, glass, ceramics and building materials, and for applications in environmental sciences, geochemistry, forensic science and archaeology. Moreover, XRF has the advantage of low cost of instrumentation and maintenance over similar techniques. As a result, the UAE, in cooperation with IAEA, is establishing a national X ray fluorescence laboratory (NXFL), hosted by the University of Sharjah, for environmental and cultural heritage applications. The 3 years project was approved by the IAEA under Technical Cooperation Program (Project UAE 0006). Scientists from two institutions, University of Sharjah (UoS) and American University of Sharjah (AUS), will be involved in establishing the lab, training the staff, running outreach workshops within the country and supervising the operation of the laboratory. The core of the scientific team is composed of four professors with excellent knowledge of the subject and extensive experience in utilizing X ray techniques in material science

  8. X-ray fluorescence analysis of titanium alloys.

    Vassilaros, G L; McKaveney, J P

    1969-02-01

    An X-ray solution method is proposed for determining major amounts of Mo, Sn and Zr in Ti alloys. The method utilizes adjacent elements in the periodic table as internal standards and has been successfully applied to levels of 3-10% Sn, 11-40% Mo and 6-20% Zr. The procedure involves three steps: dissolving the sample with a suitable acid mixture; adding the suitable internal standard at the concentration levels experimentally found to give optimum accuracy and precision; analysing the resulting solution mixture by X-ray fluorescence. Antimony was found to be a suitable internal standard for its adjacent element tin at a concentration ratio of 3:1 Sb:Sn. Niobium was successfully used for both its adjacent elements, molybdenum and zirconium, at 2:1 concentration ratios, Nb:Mo and Nb:Zr. A number of elements non-adjacent to tin, molybdenum and zirconium (i.e., copper, bromine, titanium, bismuth and tantalum) were experimentally found unsuitable as internal standards. Concentration factors of the internal standard and the adjacent elements sought were found to affect significantly the precision of analysis. PMID:18960488

  9. X-ray fluorescence in IAEA Member States: Sri Lanka

    Full text: The Energy Dispersive X-ray Fluorescence (ED-XRF) facility was established in 2001 under the Technical Cooperation project on Development and Utilization of Nuclear Analytical Technology (SRL/2/005). The XRF facility consists of X-ray tube with Mo anode, secondary targets and Si/Li detector coupled with portable inspector MCA and Genie 2000 spectrum acquisition software. Qualitative and Quantitative analysis is being carried out using QXAS-BFP (Backscatter Fundamental Parameter method) for thick samples, QAES (P.Kump, Slovenia) for both intermediate thickness and thin samples. The EDXRF facility is used for the elemental analysis of soil /sediments samples, plant materials, air filters, alloys and water samples. The analytical services are provided for research institutions, Universities, Geological and Environmental assessment companies to determine major, minor and trace elements in various materials. Since 1998 the XRF group has also participated in the IAEA/RCA project on Isotopes and related techniques to assess Air Pollution. Currently, three research projects on the application of EDXRF technique in environmental studies are being carried out (author)

  10. Determination of technetium by total reflection x-ray fluorescence

    We describe a technique using total reflection x-ray fluorescence (TXRF) for determination of Technetium produced by elution of chromatography generators with physiological saline solutions. The analysis with the 18.41 keV Kα line of Technetium was accomplished with monochromatized Kα radiation from a silver anode x-ray tube operated at 45 keV and 20 mA. This radiation at 22.104 keV is efficiently coupled to the 21.054 keV absorption edge of Tc. It is also of advantage in the direct analysis of organic and saline properties of the Tc-bearing samples. Quantification was accomplished by internal standard addition of Ga and using an interpolated value of the sensitivity for Tc between Molybdenum and Rhenium. Data processing was carried out with the QXAS-AXIL software package. System sensitivity was found adequate for direct Tc determination of eluted saline solutions. The interest and advantages of the use of the technique as an auxiliary in the synthesis and characterization of Tc-labeled radiopharmaceuticals used for diagnosis in nuclear medicine are discussed. Detection limits in the matrices analyzed are reported. (author)

  11. X-ray fluorescence in IAEA Member States: Spain

    Full text: The Archaeometry Unit (UA) of the Material Science Institute of the Valencia University (ICMUV) has got portable EDXRF spectrometers with small X-Ray tubes and thermoelectrically cooled semiconductor detectors (Cd(Zn)Te and Si-PIN). In June 2002 a new facility based on Total Reflection X-Ray Fluorescence (TXRF) analysis will also be in operation at the UA. The research activities of the UA include in situ EDXRF analysis of art objects from the Spanish Cultural Heritage. The following examples are worth mentioning: - Identification of the underglaze and overglaze cobalt blue decoration of painted ceramics from Valencia (XIV-XIX centuries). This project is carry out in collaboration with Dr. Jaume Coll from the National Ceramic and Luxurious Arts Museum 'Gonzalez Marti'. - Reconstruction of the original tonality of blue degraded smalts on canvas from the measurement of the relationship of Co/Pb. - Analyses and comparative studies of engravings elaborated with different techniques (etching and heliogravure) from the XVII - XX centuries, and EDXRF analysis of ancient and currently commercialised inks. This project is developed in collaboration with Dr. Rosa Vives from the Barcelona University. - Identification and characterization of forged works of art. - In the near future: quantitative and semi-quantitative multi-element microanalysis of solid and liquid samples by TXRF. (author)

  12. Extraction-X-ray fluorescence determination of selenium

    Easy to use, rapid x-ray fluorescence method of selenium determination is developed. The method is based on preliminary extraction of Se with dithiophosphoric acid and evaporation of the extract on a porous matrix. To choose the optimal conditions of extraction the effect of organic reagent concentration, of the pH aqueous phase and the shaking up time on selenium extraction volume is studied. Selenium quantitative extraction is observed in the process of selenium extraction from highly acid media. It is shown that the optimal conditions for Se(4) extraction by means of ammonium diethyldithiophosphate are the following: reagent concentration is 1x10-3 M; pH 0-1.5; the shaking up time is 20 min. The given methods are applied for selenium determination in the bottoms the formations of the Noksa river. The absolute detection limit is 0.1 μg

  13. Using X-ray Fluorescence to Date Petroglyphs

    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.

  14. Laboratory micro-X-ray fluorescence spectroscopy instrumentation and applications

    Haschke, Michael

    2014-01-01

    Micro-X-ray fluorescence offers the possibility for a position- sensitive and non-destructive analysis that can be used for the analysis of non-homogeneous materials and layer systems. This analytical technique has shown a dynamic development in the last 15 years and is used for the analysis of small particles, inclusions, of elemental distributions for a wide range of different applications both in research and quality control. The first experiments were performed on synchrotrons but there is a requirement for laboratory instruments which offers a fast and immediate access for analytical results. The book discuss the main components of a µ-XRF instrument and the different measurement modes, it gives an overview about the various instruments types, considers the special requirements for quantification of non-homogeneous materials and presents a wide range of application for single point and multi-point analysis as well as for distribution analysis in one, two and three dimensions.

  15. Determination of thorium by fluorescent x-ray spectrometry

    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.

  16. Analysis of tungsten carbides by X-ray fluorescence spectrometry.

    Kinson, K; Knott, A C; Belcher, C B

    Five sample presentation techniques were examined for the X-ray fluorescence spectrometric analysis of tungsten carbide alloys in powder and cemented forms. Powder samples may be oxidized by air at 600 degrees before fusion (I), or preferably by lithium nitrate during fusion (II); the fusion is effected with lithium-lanthanum tetraborate followed by briquetting with graphite. Powder samples may also be blended with wax and briquetted (III). Cemented carbides are surface-prepared with silicon carbide before analysis (V). Briquettes prepared by blending carbide powder, lithium-lanthanum tetraborate and graphite (IV), give poor reproducibility, however, owing to micro-absorption effects the technique is not recommended. The determination of eight common elements in tungsten carbide is discussed and the relative standard deviations are 0.002-0.004 for major and 0.008-0.01 for minor elements. PMID:18961988

  17. Uranium concentrate analysis by X-ray fluorescence spectroscopy

    The determination of As, Ca, Fe, Mo, P, S, Si. Th, V and U in uranium concentrates by X-ray fluorescence spectroscopy has been studied. As and U are determined in nitric solutions and for the rest of elements analysis is performed by a bead fusion technique using Li2B4O7 and Li2CO3 as fluxes. Although the uranium matrix minimizes the absorption and enhancement effects, because of the content variations of this element it is advisable to operate at a constant level of U3O8. Despite the high matrix absorption and the large dilution of the samples, sensitivity and speed are found to be satisfactory as the result of the use of a high sensitivity automatic spectrometer. The spectral interferences of Mo on S and P, and of Pb on As have been particularly considered. (author)

  18. Environmental studies in Khartoum area using x-ray fluorescence

    In the present work an attempt has been made for the analysis of some soil, plant, sediments and fish samples of relevance to environmental pollution in Khartoum area. These samples have been collected from different places in residential areas, so as to cover industrial areas, agricultural and residential areas, as well as Tuti Island as control area. Special attention has been dedicated to the analysis of lead concentrations resulting from automobile-emissions in soils and to other toxic metals such as Cr in some industries. The samples were analysed by x-ray fluorescence (XRF) technique. The results obtained using XRF measurements and computer software called QXAS for data analysis. The concentrations of lead and some heavy metals such as Cr in soils from certain locations were alarming and may create pollution problems in the near future. The results obtained from different countries. The results are generally lower than the international limits. (Author)

  19. X-ray fluorescence in IAEA Member States: Slovenia

    Full text: Research and development activities include: - development of quantification software for radioisotope and tube excited X-ray fluorescence spectrometry, based on use of fundamental parameters and emission-transmission method; - development of sensitive XRF technique for aerosol analysis, utilising excitation at small incident angles; - development of fast semi-quantitative analysis of samples in powder form by TXRF; - designing and manufacturing of portable XRF systems with radioisotope and tube excitation for use in archaeometry and for the analysis of pigments on paintings. Applications: - analysis of geological samples (geochemistry applications); - determination of P, S, Cl, K, Ca and some heavy metals in animal food (hay, grass silage and maize silage); - routine aerosol analysis in urban areas close to industrial facilities; - analysis of pigments from old paintings and other artefacts by TXRF; - analysis of vines and bee honey for the contents of S and some heavy metals by TXRF; - analysis of thin layers (Ti, Cr, Ni, and Zn ) used for anticorrosion protection. (author)

  20. Analysis of solar blocker through portable X-ray fluorescence

    This paper estimates the concentration of TiO2 by Energy Dispersion X-ray fluorescence (EDXRF) viewing t obtain the FPS due to the physical barrier in the composition of solar blockers, and identifies possible present metals in the samples. A portable EDXRF equipment was used and 27 commercial of different brands and solar protection factors were analysed. Also, three formulations (A, B and C) were prepared and measured estimated in FPS-30 using 5% or TiO2. The quantification was performed through calibration curves with 1% to 30% standards of TiO2. As result, it was possible to determine the contribution to physical protection in the FPS, associated to the Ti concentration present in some solar blocker samples available in the market. Also, it was possible to detect the presence of various metals in solar protectors, such as Fe, Zn, Br and Sr, and identify chemical elements which were not mentioned and their formulation as well

  1. X-ray fluorescence beamline at LNLS: components and some associated techniques

    Perez, CArlos A.; Radtke, Martin; Perez, Carlos; Tolentino, Helio; Vicentin, Flavio [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Sanchez, Hector Jorge; Perez, Roberto D. [Universidad Nacional, Cordoba (Argentina). Facultad de Matematica, Astronomia y Fisica

    1997-12-31

    Full text. In this work a general description of the Total Reflection X-Ray Fluorescence (TXRF) and the X-Ray Fluorescence Microprobe (XRFM) is presented. Components, equipment and experimental stations for the x-ray fluorescence beamline are described, regarding to the techniques mentioned above. Results from the simulations of a pair bended mirrors in a Kirkpatrick-Baez configuration, are shown. The simulations were performed with Shadow program. (author)

  2. X-ray fluorescence beamline at LNLS: components and some associated techniques

    Full text. In this work a general description of the Total Reflection X-Ray Fluorescence (TXRF) and the X-Ray Fluorescence Microprobe (XRFM) is presented. Components, equipment and experimental stations for the x-ray fluorescence beamline are described, regarding to the techniques mentioned above. Results from the simulations of a pair bended mirrors in a Kirkpatrick-Baez configuration, are shown. The simulations were performed with Shadow program. (author)

  3. Direct comparison of soft x-ray images of organelles with optical fluorescence images

    Soft x-ray microscopes operating in the water window region are capable of imaging living hydrated cells. Up to now, we have been able to take some soft x-ray images of living cells by the use of a contact x-ray microscope system with laser produced plasma soft x-ray source. Since the soft x-ray images are different from the optical images obtained with an ordinary microscope, it is very important to identify what is seen in the x-ray images. Hence, we have demonstrated the direct comparison between the images of organelles obtained with a fluorescence microscope and those with a soft x-ray microscope. Comparing the soft x-ray images to the fluorescence images, the fine structures of the organelles could be identified and observed. (author)

  4. Azimuthal anisotropy of the scattered radiation in grazing incidence X-ray fluorescence

    Das, Gangadhar, E-mail: gdas@rrcat.gov.in; Tiwari, M. K.; Singh, A. K.; Ghosh, Haranath [Indus Synchrotrons Utilisation Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)

    2015-06-24

    The Compton and elastic scattering radiations are the major contributor to the spectral background of an x-ray fluorescence spectrum, which eventually limits the element detection sensitivities of the technique to µg/g (ppm) range. In the present work, we provide a detail mathematical descriptions and show that how polarization properties of the synchrotron radiation influence the spectral background in the x-ray fluorescence technique. We demonstrate our theoretical understandings through experimental observations using total x-ray fluorescence measurements on standard reference materials. Interestingly, the azimuthal anisotropy of the scattered radiation is shown to have a vital role on the significance of the x-ray fluorescence detection sensitivities.

  5. X-ray fluorescence in IAEA Member States: Venezuela

    study on an in-situ microwave digestion prior to analysis of biological samples by total reflection X-ray fluorescence, Spectrochim. Acta 56B (2001) 2187-2194. L.M.Marco P., E. Jimenez, E.A. Hernandez C., A. Rojas and E.D.Greaves, Determination of Zn/Cu ratio and oligoelements in serum samples by total reflection X-ray fluorescence spectrometry for cancer diagnosis, Spectrochim. Acta 56B (2001) 2195-2202. J.I. Bermudez, E.D.Greaves. P. Nemeth and L. Sajo-Bohus, Determination of Technetium by total reflection X-ray fluorescence, Spectrochim. Acta 56B (2001) 2247-2252. L. Bennun, E.D. Greaves and J.J. Blostein, New procedure for intensity and detection limit determination in spectral trace analysis: application for trace mercury by TXRF, Accepted for publication in X-ray Spectrometry (2002). (author)

  6. Quo Vadis total reflection X-ray fluorescence?

    The multielement trace analytical method 'total reflection X-ray fluorescence' (TXRF) has become a successfully established method in the semiconductor industry, particularly, in the ultra trace element analysis of silicon wafer surfaces. TXRF applications can fulfill general industrial requirements on daily routine of monitoring wafer cleanliness up to 300 mm diameter under cleanroom conditions. Nowadays, TXRF and hyphenated TXRF methods such as 'vapor phase decomposition (VPD)-TXRF', i.e. TXRF with a preceding surface and acid digestion and preconcentration procedure, are automated routine techniques ('wafer surface preparation system', WSPS). A linear range from 108 to 1014 [atoms/cm2] for some elements is regularly controlled. Instrument uptime is higher than 90%. The method is not tedious and can automatically be operated for 24 h/7 days. Elements such as S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Sn, Sb, Ba and Pb are included in the software for standard peak search. The detection limits of recovered elements are between 1x1011 and 1x107 [atoms/cm2] depending upon X-ray excitation energy and the element of interest. For the determination of low Z elements, i.e. Na, Al and Mg, TXRF has also been extended but its implementation for routine analysis needs further research. At present, VPD-TXRF determination of light elements is viable in a range of 109 [atoms/cm2]. Novel detectors such as silicon drift detectors (SDD) with an active area of 5 mm2, 10 mm2 or 20 mm2, respectively, and multi-array detectors forming up to 70 mm2 are commercially available. The first SDD with 100 mm2 (!) area and integrated backside FET is working under laboratory conditions. Applications of and comparison with ICP-MS, HR-ICP-MS and SR-TXRF, an extension of TXRF capabilities with an extremely powerful energy source, are also reported

  7. A Versatile Field Instrument for X-Ray Fluorescence Analysis

    A portable X-ray fluorescence analyser has been developed consisting essentially of an Xe/CH4 proportional counter probe and an electronic unit with single-channel analyser, binary scaler, digital-to-analogue converter with meter- readout and an automatic gain control circuitry. The instrument utilizes the high energy resolution of proportional counters combined with the excellent long-term stability provided by automatic gain control (AGC). The radioactive source, 241Am, is suitable for the excitation of fluorescence X-rays in a wide range of elements, i.e. from Cr-K (Z = 24) to Tm-K (Z = 69) and from Ba-L (Z = 56) to U-L (Z = 92). The same source is simultaneously used for the AGC operation by measuring a small fraction of the 241Am gamma- radiation(59.6 keV) directly incident through a small collimator hole into the detector. The count-rate measured above a threshold at 57 keV, which is not affected by any other fluorescent or scattered radiation, is used to control the detector high voltage in order to obtain a constant energy calibration and to eliminate any drift of the detector and the electronics. Thus several fixed single-channel windows selected by a rotary switch can be set for various elements of interest. Once having been set in the laboratory no further calibration is necessary for field operation. The prototype of the instrument was originally developed and used to determine nickel coatings on steel, which necessitates a very high energy resolution of the detector. Without using filters a sufficient sensitivity could be obtained. The same probe can also be equipped with balanced filters and the electronic unit with a reversible scaler providing direct indication of the difference counting rate of the meter, without fluctuations. However, in many cases filters can be saved because of the high energy resolution of the detector. The design features of the instrument make it extremely suitable for a wide range of prospecting and mining applications

  8. X-ray fluorescence in IAEA Member States: Spain

    Full text: Instrumental facilities of the ICMUV include: a total reflection X ray fluorescence (TXRF) spectrometer, and laboratory and portable energy-dispersive X ray fluorescence (EDXRF) spectrometer. These instruments are applied in the field of art and archaeometry. Current projects are in collaboration with the Department of Prehistory and Archaeology (University of Valencia), the Valltorta Museum and Vetraria Munoz de Pablos S.L. In situ analysis of rock art painting by portable EDXRF spectrometry in the Valltorta Valley, East of Spain: A purpose of the research was to investigate the elemental composition of the prehistoric cave paintings located in the Valltorta Valley in Coves de Vinroma (Castellon, Spain) and to demonstrate the usefulness of portable EDXRF spectroscopy for in situ elemental analysis. Analysis of the red and black pigments by portable EDXRF showed the presence of iron and manganese compounds, respectively; in the future it will facilitate sampling decisions prior to use of other analytical methods to obtain additional information about chemical composition, structure and preparation techniques. Application of portable EDXRF system to the study of ancient glasses: Since there is no method available to determine directly the age of glass objects, it is necessary to compare the material composition of questionable pieces with genuine pieces. Therefore, a non-destructive and sensitive analytical technique was needed with a capability to perform in-situ measurements in order to avoid transportation of precious and fragile objects to the analytical laboratory. A portable EDXRF system meets these requirements more than adequately. The application of a portable XRF spectrometer for solving authenticity-related problems in the field of ancient glasses has demonstrated its capability for revealing essential information for study of the Stained Glass Windows of Avila Cathedral. During the restoration work, clear differences in the composition of

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

    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. Experimental demonstration of direct L-shell x-ray fluorescence imaging of gold nanoparticles using a benchtop x-ray source

    Manohar, Nivedh; Reynoso, Francisco J.; Cho, Sang Hyun

    2013-01-01

    Purpose: To develop a proof-of-principle L-shell x-ray fluorescence (XRF) imaging system that locates and quantifies sparse concentrations of gold nanoparticles (GNPs) using a benchtop polychromatic x-ray source and a silicon (Si)-PIN diode x-ray detector system.

  11. Application of confocal X-ray fluorescence micro-spectroscopy to the investigation of paint layers

    A confocal micro X-ray fluorescence (MXRF) spectrometer based on polycapillary X-ray optics was used for the identification of paint layers. The performance of the confocal MXRF was studied. Multilayered paint fragments of a car were analyzed nondestructively to demonstrate that this confocal MXRF instrument could be used in the discrimination of the various layers in multilayer paint systems. - Hihglights: • The performance of the confocal micro X-ray fluorescence was studied. • Confocal micro X-ray fluorescence was used for identifying paint layers. • The multilayered paint fragments of a car were analyzed nondestructively

  12. Investigation of a tabletop confocal micro X-ray fluorescence setup

    A new tabletop confocal micro x-ray fluorescence setup with an MCBM 50-0.6B x-ray tube is assembled. The confocal micro x-ray fluorescence setup includes two lenses, a polycapillary full lens in the excitation channel and a polycapillary half lens in the detection channel. A Ni-Cr wire in diameter 25 μm is used to investigate the FWHM of three-dimensional confocal volume, A basso-relievo capital letter of a 1-jiao RMB coin of 2005 version is studied with this confocal micro x-ray fluorescence setup. (authors)

  13. X-ray fluorescence in IAEA Member States: Argentina

    Full text: The following projects carried out by the XRF Group are described: 1. Iridium Detection by Total Reflection x-Ray Fluorescence in Samples Providing from The Cretaceous-Tertiary Boundary and Experimental Amphibian Embryos - The main purpose of this study is to report the high sensitivity of TXRF for Ir measurements in mineral and biological samples. Mineral samples originate from different horizon deposits in the Neuquen basin, Argentina. Ir anomaly seems to be related to diderophite material provided to Earth in large quantities most probably by a 10 km asteroid that impacted earth 65 Myears ago. Sample preparation procedures and multielemental information are available. In a particular case of amphibian embryos, the detected level of Ir was in the order of 1 part per million (bioconcentration factor of 9). 2. Polymer Solutions on Glass: Adsorption Study by Total Reflection x-Ray Fluorescence - Equilibrium properties of a polymer solution in the vicinity of a solid-liquid interface are locally altered relative to the properties in bulk. This is caused probably by attractive or repulsive interactions adsorbed fraction-adsorbent. In this way, theoretical models for flexible and rod-like polymers were published.The present work is related to study of the adsorption of 0 to 0.05% aqueous scleroglucan solution on 400 to 600 μm glass microspheres. This study was possible by labeling the macromolecule by means of a chemical reaction with iodine, and then detecting by TXRF. Results show that for dilute concentration polymers behave in an anomalous way near the interface, contrary to the previous theoretical predictions. A first attempt to explain this behavior is presented. 3. Total Reflection x-Ray Fluorescence Polymer Spectra: Classification By Taxonomy Statistic Tools - The aim of this work is to explore the use of chemometric tools for the classification of synthetic and natural polymers with a mean molecular weight greater than 106. Spectra obtained by

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

    Warner, Benjamin P.; Havrilla, George J.; Miller, Thomasin C.; Lewis, Cris; Mahan, Cynthia A.; Wells, Cyndi A.

    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. X-ray fluorescence in Member States: Argentina. Synchrotron radiation total reflection X-ray fluorescence study of gums

    Full text: Over the years, the term gums has been used for a wide range of compounds including polysaccharides, terpenes, proteins, and synthetic polymers. In the 1990s, the term more specifically denotes a group of industrially useful polysaccharides or their derivatives that hydrate in hot or cold water to form viscous solutions, dispersions, or gels. Gums are used in industry because their aqueous solutions or dispersions have suspending and stabilizing properties. In addition, gums may produce gels or act as emulsifiers, adhesives, flocculants, binders, film formers, lubricants, or friction reducers, depending on the shape and chemical nature of the particular gum. They have increasingly been used in recent years by industry due to their controlled, reproducible and economical biosynthesis, and their biodegradability. Gums are classified as natural or modified. Natural gums include seaweed extracts, plant exudates, gums from seed or root, and gums obtained by microbial fermentation. Modified (semi-synthetic) gums include cellulose and starch derivatives and certain synthetic gums such as low methoxyl pectin, propylene glycol alginate, and carboxymethyl and hydroxypropyl guar gum. Selected polymers from the different groups were characterised in this work. Specifications of these polymers have to be controlled by European Community, Mercosur, etc. especially for toxic metals in food and pharmaceutical products. Synchrotron Radiation (SR) induced Total Reflection X-ray Fluorescence (SRTXRF) analysis expands the possibilities of conventional TXRF based on X-ray tube excitation. In this study the SRTXRF technique was successfully applied for the quantification of F, Na, Mg, S, K, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, As and Pb in high-viscosity gum aqueous solutions. The results were analysed from both toxic and alimentary point of view. (author)

  16. High-throughput screening with micro-x-ray fluorescence

    Micro-x-ray fluorescence (MXRF) is a useful characterization tool for high-throughput screening of combinatorial libraries. Due to the increasing threat of use of chemical warfare (CW) agents both in military actions and against civilians by terrorist extremists, there is a strong push to improve existing methods and develop means for the detection of a broad spectrum of CW agents in a minimal amount of time to increase national security. This paper describes a combinatorial high-throughput screening technique for CW receptor discovery to aid in sensor development. MXRF can screen materials for elemental composition at the mesoscale level (tens to hundreds of micrometers). The key aspect of this work is the use of commercial MXRF instrumentation coupled with the inherent heteroatom elements within the target molecules of the combinatorial reaction to provide rapid and specific identification of lead species. The method is demonstrated by screening an 11-mer oligopeptide library for selective binding of the degradation products of the nerve agent VX. The identified oligopeptides can be used as selective molecular receptors for sensor development. The MXRF screening method is nondestructive, requires minimal sample preparation or special tags for analysis, and the screening time depends on the desired sensitivity

  17. High-throughput screening with micro-x-ray fluorescence

    Havrilla, George J.; Miller, Thomasin C.

    2005-06-01

    Micro-x-ray fluorescence (MXRF) is a useful characterization tool for high-throughput screening of combinatorial libraries. Due to the increasing threat of use of chemical warfare (CW) agents both in military actions and against civilians by terrorist extremists, there is a strong push to improve existing methods and develop means for the detection of a broad spectrum of CW agents in a minimal amount of time to increase national security. This paper describes a combinatorial high-throughput screening technique for CW receptor discovery to aid in sensor development. MXRF can screen materials for elemental composition at the mesoscale level (tens to hundreds of micrometers). The key aspect of this work is the use of commercial MXRF instrumentation coupled with the inherent heteroatom elements within the target molecules of the combinatorial reaction to provide rapid and specific identification of lead species. The method is demonstrated by screening an 11-mer oligopeptide library for selective binding of the degradation products of the nerve agent VX. The identified oligopeptides can be used as selective molecular receptors for sensor development. The MXRF screening method is nondestructive, requires minimal sample preparation or special tags for analysis, and the screening time depends on the desired sensitivity.

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

    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

  19. A Brazilian tree collection analyzed by X ray fluorescence

    The analysis of the inorganic components of wood is of great interest for several reasons, including the acquisition of basic data creating a data base of values for individual species. Knowing the wide variability in matrix composition (lignin, oil, resin, silica) and densities (0.39-1.09 g cm-3), 40 species of trees were analysed by X ray fluorescence (XRF) to determine the concentrations of Br, Ca, Cu, K, Mn, Pb, Rb, Sr, and A. This technique is widely used because of its accuracy and simplicity of sample preparation, normally complex for this type of biological material. This multi-elemental analysis has proven suitable for wood, a material in which a wide range for each element was encountered in the different species studied: 0.3-5.2 for Br, 126-9074 for Ca, 2.2-11 for Cu, 108-5873 for K, 3.1-134 for Mn, 0.5-4.7 for Pb, 0.3-20 for Rb, 1.2-120 for Sr, and 1.1-20 for Zn (values given in μg g-1). (author)

  20. Pinhole X-ray Fluorescence Imaging of Gadolinium Nanoparticles: A Preliminary Monte Carlo Study

    Jung, Seong Moon; Sung, Won Mo; Ye, Sung Joon [Seoul National University, Seoul (Korea, Republic of)

    2014-10-15

    X-ray fluorescence imaging is a modality for the element-specific imaging of a subject through analysis of characteristic x-rays produced by exploiting the interaction of high atomic number elements and incoming x-rays. Previous studies have utilized a polychromatic x-ray source to investigate the production of in vivo x-ray fluorescence images for the assessment of concentrations and locations of gold nanoparticles. However, previous efforts have so far been unable to detect low concentrations, such as 0.001% gold by weight, which is an expected concentration accumulated in tumors. We examined the feasibility of a monochromatic synchrotron x-rays implementation of pinhole x-ray fluorescence imaging by Monte Carlo simulations using MCNP5. In the current study, gadolinium (Gd) nanoparticles, which have been widely used as a contrast agent in magnetic resonance imaging and also as a dose enhancer in radiation therapy, were chosen for tumor targeting. Since a monochromatic x-ray source is used, the increased x-ray fluorescence signals allow the detection of low concentrations of Gd. Two different monochromatic x-ray beam energies, 50.5 keV near the Kedge energy (i.e., 50.207 keV) of Gd and 55 keV, were compared by their respective imaging results. Using Monte Carlo simulations the feasibility of imaging low concentrations of Gd nanoparticles (e.g., 0.001 wt%) with x-ray fluorescence using monochromatic synchrotron x-rays of two different energies was shown. In the case of imaging a single Gd column inserted in the center of a water phantom, the fluorescence signals from 0.05 wt% and 0.1 wt% Gd columns irradiated with a 50.5 keV photon beam were higher than those irradiated with 55 keV. Below 0.05 wt% region no significant differences were found.

  1. Pinhole X-ray Fluorescence Imaging of Gadolinium Nanoparticles: A Preliminary Monte Carlo Study

    X-ray fluorescence imaging is a modality for the element-specific imaging of a subject through analysis of characteristic x-rays produced by exploiting the interaction of high atomic number elements and incoming x-rays. Previous studies have utilized a polychromatic x-ray source to investigate the production of in vivo x-ray fluorescence images for the assessment of concentrations and locations of gold nanoparticles. However, previous efforts have so far been unable to detect low concentrations, such as 0.001% gold by weight, which is an expected concentration accumulated in tumors. We examined the feasibility of a monochromatic synchrotron x-rays implementation of pinhole x-ray fluorescence imaging by Monte Carlo simulations using MCNP5. In the current study, gadolinium (Gd) nanoparticles, which have been widely used as a contrast agent in magnetic resonance imaging and also as a dose enhancer in radiation therapy, were chosen for tumor targeting. Since a monochromatic x-ray source is used, the increased x-ray fluorescence signals allow the detection of low concentrations of Gd. Two different monochromatic x-ray beam energies, 50.5 keV near the Kedge energy (i.e., 50.207 keV) of Gd and 55 keV, were compared by their respective imaging results. Using Monte Carlo simulations the feasibility of imaging low concentrations of Gd nanoparticles (e.g., 0.001 wt%) with x-ray fluorescence using monochromatic synchrotron x-rays of two different energies was shown. In the case of imaging a single Gd column inserted in the center of a water phantom, the fluorescence signals from 0.05 wt% and 0.1 wt% Gd columns irradiated with a 50.5 keV photon beam were higher than those irradiated with 55 keV. Below 0.05 wt% region no significant differences were found

  2. X-ray fluorescence in IAEA Member States: Spain

    Full text: Instrumental facilities of the ICMUV include: a Total-reflection X-Ray Fluorencence (TXRF), a static and a portable Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometers. These equipments are employed in the field of the art and archaeometry, and some applications in this area are implemented. The portable EDXRF spectrometer is advisable to perform 'in situ' and on-line analysis in a multidisciplinary environment, the static EDXRF equipment is good to perform analysis on paper and metal pieces. The TXRF spectrometry is the best technique for very sensitive analysis of trace elements in microsamples. Using the last technique we have analyzed the cottons used by the restorers in the different steps of the restoration process; it appeared that the method is a good tool to study the composition of different layers and zones of the work of art. Current projects include: 1. Analysis of valuable antique ceramics that can be investigated only when the analysis does not result in any damage. EDXRF measurements with portable instrumentation provide non-destructive analysis that completely eliminates sampling. An alternative method to determine the overglaze or underglaze pigment decoration is the microscopic examination of a ceramic cross section, but this examination requires sampling and damage to the physical integrity of the object. The aim of our work is to apply nondestructive technique ensuring the physical integrity of the object. We have proposed a portable EDXRF spectrometer to identify the underglaze and overglaze pigment decoration of ceramics on the basis of different values for the ratio between the Pb(Lα) line from the main element of the glaze cover and the Kα lines from the main elements (Co, Mn, Ni) found in the pigment, when the angle of the incidence radiation is varied. If the position of the detector is fixed, these ratios (Pb(Lα)/Co(Kα), etc.) increases with the angle for underglaze decoration, and decreases for overglaze decoration

  3. Quantitative x-ray fluorescence analysis using monochromatic synchrotron radiation

    The use of high-intensity, tunable monochromatic x-rays for the quantitative analysis of biological and geochemical specimens at the 10-8 g level is described. Incident x-rays were obtained from the new LBL-EXXON permanent magnet wiggler beamline at the Stanford Synchrotron Radiation Laboratory. The sample detector geometry was designed to make optimal use of polarization advantages for background reduction. Questions regarding the sensitivity and accuracy of the measurements were studied with particular emphasis on the advantages of tuning the x-ray energies for optimum excitation for specific elements. The implications of these measurements with respect to the use of x-ray microprobe beams will be discussed

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

    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

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

    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 100μm. 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 large earrings

  6. Measurement uncertainty in Total Reflection X-ray Fluorescence

    Total Reflection X-ray Fluorescence (TXRF) spectrometry is a multi-elemental technique using micro-volumes of sample. This work assessed the components contributing to the combined uncertainty budget associated with TXRF measurements using Cu and Fe concentrations in different spiked and natural water samples as an example. The results showed that an uncertainty estimation based solely on the count statistics of the analyte is not a realistic estimation of the overall uncertainty, since the depositional repeatability and the relative sensitivity between the analyte and the internal standard are important contributions to the uncertainty budget. The uncertainty on the instrumental repeatability and sensitivity factor could be estimated and as such, potentially relatively straightforward implemented in the TXRF instrument software. However, the depositional repeatability varied significantly from sample to sample and between elemental ratios and the controlling factors are not well understood. By a lack of theoretical prediction of the depositional repeatability, the uncertainty budget can be based on repeat measurements using different reflectors. A simple approach to estimate the uncertainty was presented. The measurement procedure implemented and the uncertainty estimation processes developed were validated from the agreement with results obtained by inductively coupled plasma — optical emission spectrometry (ICP-OES) and/or reference/calculated values. - Highlights: • The uncertainty of TXRF cannot be realistically described by the counting statistics. • The depositional repeatability is an important contribution to the uncertainty. • Total combined uncertainties for Fe and Cu in waste/mine water samples were 4–8%. • Obtained concentrations agree within uncertainty with reference values

  7. X-ray fluorescence in IAEA Member States: Nigeria

    Full text: Environmental Research Laboratory (ERL) has got EDXRF system with total reflection module. These facilities are used for training, research and analytical services. Training is provided for Physics, Chemistry and Geology for both undergraduate and postgraduate students. The samples analysed in our laboratory include environmental, geological, biological, water, steel and alloy materials. The Research activities are carried out in support of environmental studies for air, water, soils and plant materials and optimisation of measurement protocols. We provides analytical services for the determination of major and minor elements in small-scale prospectors and miners of mineral ores with major constituents such as K, Ca, Ti, Cr, Mn, As, Pb and Zr. Presently we are monitoring environmental pollution due to toxic heavy metals in industrial workplaces. Other analytical services rendered by the laboratory include determination of trace elements in Nigerian bitumen samples, determination of toxic heavy metals like Ti, Cr, Mn, Fe, Cu, Zn, As, Pb, Cd, Hg in various stages of dam water in Ile-Ife- the university community. The laboratory also offered analytical services to other research institutions, Universities, governmental agencies, geological and environmental assessment companies. ERL group is currently participating in different projects/conferences organized by the International Atomic Energy Agency (IAEA), Vienna with the following papers presented: (1) Determination of atmospheric concentration of toxic metals along urban motorway in two Nigerian cities using TXRF technique (2) Assessment of Occupational Exposure to Toxic Metals in some Paint and Secondary Iron and Steel Industries in Lagos, Nigeria using TXRF Technique. One of the postgraduate projects already completed is on Determination of Concentration of Toxic Metals in the Ambient Air in Lagos and Ile-Ife, Nigeria, using Total Reflection X-ray Fluorescence Technique. (author)

  8. Measurement uncertainty in Total Reflection X-ray Fluorescence

    Floor, G.H., E-mail: geerke.floor@gfz-potsdam.de [GFZ German Research Centre for Geosciences Section 3.4. Earth Surface Geochemistry, Telegrafenberg, 14473 Postdam (Germany); Queralt, I. [Institute of Earth Sciences Jaume Almera ICTJA-CSIC, Solé Sabaris s/n, 08028 Barcelona (Spain); Hidalgo, M.; Marguí, E. [Department of Chemistry, University of Girona, Campus Montilivi s/n, 17071 Girona (Spain)

    2015-09-01

    Total Reflection X-ray Fluorescence (TXRF) spectrometry is a multi-elemental technique using micro-volumes of sample. This work assessed the components contributing to the combined uncertainty budget associated with TXRF measurements using Cu and Fe concentrations in different spiked and natural water samples as an example. The results showed that an uncertainty estimation based solely on the count statistics of the analyte is not a realistic estimation of the overall uncertainty, since the depositional repeatability and the relative sensitivity between the analyte and the internal standard are important contributions to the uncertainty budget. The uncertainty on the instrumental repeatability and sensitivity factor could be estimated and as such, potentially relatively straightforward implemented in the TXRF instrument software. However, the depositional repeatability varied significantly from sample to sample and between elemental ratios and the controlling factors are not well understood. By a lack of theoretical prediction of the depositional repeatability, the uncertainty budget can be based on repeat measurements using different reflectors. A simple approach to estimate the uncertainty was presented. The measurement procedure implemented and the uncertainty estimation processes developed were validated from the agreement with results obtained by inductively coupled plasma — optical emission spectrometry (ICP-OES) and/or reference/calculated values. - Highlights: • The uncertainty of TXRF cannot be realistically described by the counting statistics. • The depositional repeatability is an important contribution to the uncertainty. • Total combined uncertainties for Fe and Cu in waste/mine water samples were 4–8%. • Obtained concentrations agree within uncertainty with reference values.

  9. [Methods of detector response function establishment in X-ray fluorescence spectra analysis].

    Li, Zhe; Tuo, Xian-Guo; Yang, Jian-Bo; Liu, Ming-Zhe; Cheng, Yi; Wang, Lei; Zhou, Jian-Bin

    2012-11-01

    During the measurement and analysis process of X-ray fluorescence spectra, it is very helpful to improve the analyze speed, accuracy and automaticity of X-ray fluorescence spectra analysis by establishing detector response function(DRF), which represents the shape of full energy peak and can provide former basic data for subsequent X-ray analysis technique. For the theory and model of semiconductor DRF in X-ray energy spectrum measurements, methods of three typical detector response function model establishment, key parameters of full energy peak standard deviation and Fano factor calculation, etc. are discussed, and meanwhile, the summarization and contrast of existing studies are shown in this paper. Finally, the suggestion for modeling methods of DRF in X-ray fluorescence spectra measurements is provided. PMID:23387190

  10. 3D micro-XRF for cultural heritage objects: new analysis strategies for the investigation of the Dead Sea Scrolls.

    Mantouvalou, Ioanna; Wolff, Timo; Hahn, Oliver; Rabin, Ira; Lühl, Lars; Pagels, Marcel; Malzer, Wolfgang; Kanngiesser, Birgit

    2011-08-15

    A combination of 3D micro X-ray fluorescence spectroscopy (3D micro-XRF) and micro-XRF was utilized for the investigation of a small collection of highly heterogeneous, partly degraded Dead Sea Scroll parchment samples from known excavation sites. The quantitative combination of the two techniques proves to be suitable for the identification of reliable marker elements which may be used for classification and provenance studies. With 3D micro-XRF, the three-dimensional nature, i.e. the depth-resolved elemental composition as well as density variations, of the samples was investigated and bromine could be identified as a suitable marker element. It is shown through a comparison of quantitative and semiquantitative values for the bromine content derived using both techniques that, for elements which are homogeneously distributed in the sample matrix, quantification with micro-XRF using a one-layer model is feasible. Thus, the possibility for routine provenance studies using portable micro-XRF instrumentation on a vast amount of samples, even on site, is obtained through this work. PMID:21711051

  11. X-ray fluorescence in IAEA Member States: Albania

    Full text: The activities on Energy-Dispersive X-ray Fluorescence Laboratory at the Institute of Nuclear Physics (INP) in Tirana, Albania started about 30 years ago from using simple systems consisting of single channel analysers, radioisotope sources and gas proportional or scintillation counters along with balanced filters for the separation of analytical lines. These systems were applied for the determination of single elements. A few portable prototypes were developed and successfully used for the determination of chromium and copper in ores, both in the lab and institute (ore processing plants) conditions. Later, through different TC projects with IAEA, the lab has been equipped with the following systems: X-ray tube excited EDXRF spectrometer with secondary target excitation; radioisotope excited EDXRF system; TXRF module; field portable XRF system based on a Cd-109 disc source; Si-PIN detector and pocket MCA. From the beginning our work has been focused on research, applications and training. Due to the fact that our EDXRF systems are made of different parts that are put together, our research activities are mainly related to optimization of excitation geometry and the development of optimized analytical procedures for the analysis of different group of elements in several kinds of samples. Some of these procedures include: determination of major and minor elements in soils, sediments, mineral ores and different type of rocks; determination of sulphur and some trace elements (V, Ni, etc.) in oil, bitumen and asphaltene; determination of some trace metals in sea and surface waters; determination of elemental composition of aerosols loaded on filters; determination of some trace elements in biological samples. An important point of our work is related with the quality of the analytical results. For this reason we have participated in some of the intercomparison runs organized by AQCS of the IAEA and in the GeoPT proficiency tests. In most cases our reported

  12. Sampling, storage and sample preparation procedures for X ray fluorescence analysis of environmental materials

    X ray fluorescence (XRF) method is one of the most commonly used nuclear analytical technique because of its multielement and non-destructive character, speed, economy and ease of operation. From the point of view of quality assurance practices, sampling and sample preparation procedures are the most crucial steps in all analytical techniques, (including X ray fluorescence) applied for the analysis of heterogeneous materials. This technical document covers recent modes of the X ray fluorescence method and recent developments in sample preparation techniques for the analysis of environmental materials. Refs, figs, tabs

  13. X-ray fluorescence analyzers for investigating postmediaeval pottery from Southern Moravia

    Trojek, Tomas [Department of Dosimetry and Application of Ionizing Radiation, Czech Technical University in Prague (Czech Republic)], E-mail: tomas.trojek@fjfi.cvut.cz; Hlozek, Matin [Department of Archaeology and Museology, Faculty of Arts, Masaryk University, Brno (Czech Republic); Cechak, Tomas; Musilek, Ladislav [Department of Dosimetry and Application of Ionizing Radiation, Czech Technical University in Prague (Czech Republic)

    2010-04-15

    This paper deals with an investigation of ceramic archaeological finds with the use of in-situ X-ray fluorescence analysis. Firstly, three configurations of X-ray fluorescence analyzers constructed and used at the Czech Technical University in Prague are described and compared for use in a non-destructive survey of siliceous materials. Detection limits, depth of analysis, the relation of the analyzed area, the homogeneity of the samples, and variations in the element concentrations are discussed. Secondly, many shards of postmediaeval pottery from Southern Moravia are analyzed with X-ray fluorescence analysis and some of them also with electron microprobe analysis. Selected results are described.

  14. X-ray fluorescence analyzers for investigating postmediaeval pottery from Southern Moravia

    This paper deals with an investigation of ceramic archaeological finds with the use of in-situ X-ray fluorescence analysis. Firstly, three configurations of X-ray fluorescence analyzers constructed and used at the Czech Technical University in Prague are described and compared for use in a non-destructive survey of siliceous materials. Detection limits, depth of analysis, the relation of the analyzed area, the homogeneity of the samples, and variations in the element concentrations are discussed. Secondly, many shards of postmediaeval pottery from Southern Moravia are analyzed with X-ray fluorescence analysis and some of them also with electron microprobe analysis. Selected results are described.

  15. Extraction x-ray fluorescence determination of scandium in technological solutions

    Combined extraction x-ray fluorescence method of scandium determination in technological solutions of metallurgy is suggested. 10-20 % mass solution of HDEHP in crude fraction of higher carboxylic acids (HCA) was used as extractant. Scandium is extracted completely by HCA-HDEHP melt even from acid solutions. This enables to extract it selectively from technological solutions. The prepared solid extracts represent finished targets for x-ray fluorescence analysis. It is shown that scandium determination by extraction x-ray fluorescence method enables to decrease the relatice standard deviation, improve rapidity of determination. The lower limit of determination - 0.001 %

  16. X-ray fluorescence analyzers for investigating postmediaeval pottery from Southern Moravia.

    Trojek, Tomás; Hlozek, Matin; Cechák, Tomás; Musílek, Ladislav

    2010-01-01

    This paper deals with an investigation of ceramic archaeological finds with the use of in-situ X-ray fluorescence analysis. Firstly, three configurations of X-ray fluorescence analyzers constructed and used at the Czech Technical University in Prague are described and compared for use in a non-destructive survey of siliceous materials. Detection limits, depth of analysis, the relation of the analyzed area, the homogeneity of the samples, and variations in the element concentrations are discussed. Secondly, many shards of postmediaeval pottery from Southern Moravia are analyzed with X-ray fluorescence analysis and some of them also with electron microprobe analysis. Selected results are described. PMID:19914840

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

    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−1 is given

  18. Microprocessor-based system for automatic X-ray diffraction and fluorescence

    A data acquisition and processing device appropriate for X-ray analysis and goniometer control was built. The Z-80 based system as well as the whole architeture is described. The advantages and new possibilities of the automated instrument as compared to the traditional ones are listed. The X-ray diffraction and fluorescence techniques can take advantage of the automation. (Author)

  19. Determination of platinum in ores by a combined fire assay-X-ray fluorescence method

    A combined fire assay-X-ray fluorescence procedure for the determination of platinum in ores is described. Silver beads obtained by cupellation in the classical fire assay process are flattened to constant thickness before placement in the X-ray beam. A standard plot of platinum-silver intensity ratio versus platinum concentration is used to measure the platinum content of ore samples

  20. A POLYNOMIAL CORRECTION TECHNIQUE USING RhKα COMPTON PEAK IN X-RAY FLUORESCENCE SPECTROMETRY

    包生祥

    2003-01-01

    @@ Compton scattering radiation of an X ray tube target line is widely used for matrix absorption correction in X-ray fluorescence analysis of heavy trace elements in light matrix samples,Compton scatter ing internal standard technique has been a routine method in geological samples since Reynolds recommended the method in 1963.

  1. X-ray fluorescence in IAEA Member States: Mongolia

    Full text: The Nuclear Research Center for Research and Training has got three EDXRF systems with isotopic sources (Cd-109, Am-241), secondary target and total reflection module. These facilities are used for training, research and analytical services. Training is provided for students of Physics and Chemistry at both undergraduate and postgraduate levels. The samples analyzed consist essentially of environmental, geological, biological, steel and alloy materials. Research activities are carried out in the areas of mineral resources and environmental studies (including analysis of air, water, biological and geological materials) and optimization of the measurement protocols. Since 1976 the Radioisotope EDXRF system has been used for the determination of major and minor elements in copper-molybdenum and polymetallic ores samples in support of effective exploitation of mineral resources. With Cd-109 excitation the Cu-Mo ores and tail samples are analyzed for the contents of major elements, such as Cr, Mn, Fe, Cu, Zn, As, Pb, Zr and Mo. With Am-241 excitation the Cu and Mo concentrates are analyzed for major elements such as Cu, Mo, Fe and minor toxic elements such as As, Sb and Ag. Since 1993 the TXRF system has been used for determination of toxic heavy metals (Ti, Cr, Mn, Fe, Cu, Zn, As, Pb, Cd, Hg) and other trace elements in water, alcohol, products of fermentation and food samples. This technique appeared to be extremely useful for environmental studies and pollution monitoring. The analytical services are provided for research institutions, universities, governmental agencies, geological and environmental assessment companies, prospectors and miners. Other analytical services include the determination of trace elements in soil, sediment and rock samples. The XRF group has also participated in different projects organized by the IAEA. Under a Coordinated Research Project (CRP) on 'In-situ Applications of X-Ray Fluorescence Techniques' a portable XRF analyzer

  2. X-ray fluorescence in IAEA Member States: Greece

    The Laboratory of Material Analysis (LMA) of the Institute of Nuclear Physics (INP) at the National Center for Scientific Research (NCSR) 'Demokritos', has been involved very actively during the past few years in the development, evaluation and analytical application of portable X-Ray Fluorescence (XRF) instruments, applied in particular for the non-destructive analysis of cultural materials. The study, conservation and preservation of cultural materials are considered nowadays issues of main concern for countries and international cultural organizations. Due to the strong interest and motivation from archaeologists, conservators and archaeometrical scientists in Greece and elsewhere, a large network has been developed involving the LMA and archaeologists/conservator scientists from Museums (Benaki Museum in Athens), Cultural Foundations (Thera Foundation P. Nomikos), the Greek Ministry of Culture-Conservation Department, Foreign Schools in Greece (American School of Classical Studies, French School of Athens), Universities (Department of Conservation of Antiquities and Works of Art in the Technological Educational Institution of Athens, University of Cincinnatti, Universite de Paris I, Pantheon Sorbonne), private sectors (THETIS, Thetis Authentics - Science and Techniques for Art History Conservation Ltd) and Institutions (Centre de Recherche et de Rastauration des Musees de France, LNS-INFN, LANDIS group). A variety of cultural materials/artifacts have been examined so far, including ceramic vases with colored decoration, bronze artifacts, wall-painting pigments, traces of polychromy on marble sculptures, Gold and Silver ancient jewelry, Gemstones, Roman Coins. Our research and analytical applications of the in-situ XRF analysis have been focused so far on the following: 1) optimum selection and integration of portable XRF instrumentation for improving analytical and sensitivity range; 2) evaluation of the potential of in-situ XRF analysis to provide specific

  3. Laboratory-based micro-X-ray fluorescence setup using a von Hamos crystal spectrometer and a focused beam X-ray tube

    Kayser, Y.; Błachucki, W.; Dousse, J.-Cl.; Hoszowska, J.; Neff, M.; Romano, V.

    2014-04-01

    The high-resolution von Hamos bent crystal spectrometer of the University of Fribourg was upgraded with a focused X-ray beam source with the aim of performing micro-sized X-ray fluorescence (XRF) measurements in the laboratory. The focused X-ray beam source integrates a collimating optics mounted on a low-power micro-spot X-ray tube and a focusing polycapillary half-lens placed in front of the sample. The performances of the setup were probed in terms of spatial and energy resolution. In particular, the fluorescence intensity and energy resolution of the von Hamos spectrometer equipped with the novel micro-focused X-ray source and a standard high-power water-cooled X-ray tube were compared. The XRF analysis capability of the new setup was assessed by measuring the dopant distribution within the core of Er-doped SiO2 optical fibers.

  4. Some application of the X-ray fluorescence by radioisotopic excitation on rocks and ores

    This work presents some principal concepts in which is founded the X-ray fluorescence, by radioisotopic stimulation technic. In the next itens the factors responsible by the introduction of the error in the dosage, and the analytical process are analysed. Some of possible applications of this methodology, principally in the mineral research, following this technique is compared with others analytical methods, including the conventional, X-ray fluorescence. (C.D.G.)

  5. Forensic application of total reflection X-ray fluorescence spectrometry for elemental characterization of ink samples

    Dhara, Sangita [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Misra, N.L., E-mail: nlmisra@barc.gov.i [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Maind, S.D. [NAA Unit of Central Forensic Science Laboratory Hyderabad at Analytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kumar, Sanjukta A. [Analytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Chattopadhyay, N. [NAA Unit of Central Forensic Science Laboratory Hyderabad at Analytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Aggarwal, S.K. [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2010-02-15

    The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative differentiation of documents printed with rare earth tagged and untagged inks has been explored in this paper. For qualitative differentiation, a very small amount of ink was loosened from the printed documents by smoothly rubbing with a new clean blade without destroying the manuscript. 50 muL of Milli-Q water was put on this loose powder, on the manuscript, and was agitated by sucking and releasing the suspension two to three times with the help of a micropipette. The resultant dispersion was deposited on quartz sample support for Total Reflection X-ray Fluorescence measurements. The Total Reflection X-ray Fluorescence spectrum of tagged and untagged inks could be clearly differentiated. In order to see the applicability of Total Reflection X-ray Fluorescence for quantitative determinations of rare earths and also to countercheck such determinations in ink samples, the amounts of rare earth in painted papers with single rare earth tagged inks were determined by digesting the painted paper in HNO{sub 3}/HClO{sub 4}, mixing this solution with the internal standard and recording their Total Reflection X-ray Fluorescence spectra after calibration of the instrument. The results thus obtained were compared with those obtained by Inductively Coupled Plasma Mass Spectrometry and were found in good agreement. The average precision of the Total Reflection X-ray Fluorescence determinations was 5.5% (1sigma) and the average deviation of Total Reflection X-ray Fluorescence determined values with that of Inductively Coupled Plasma Mass Spectrometry was 7.3%. These studies have shown that Total Reflection X-ray Fluorescence offers a promising and potential application in forensic work of this nature.

  6. Forensic application of total reflection X-ray fluorescence spectrometry for elemental characterization of ink samples

    The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative differentiation of documents printed with rare earth tagged and untagged inks has been explored in this paper. For qualitative differentiation, a very small amount of ink was loosened from the printed documents by smoothly rubbing with a new clean blade without destroying the manuscript. 50 μL of Milli-Q water was put on this loose powder, on the manuscript, and was agitated by sucking and releasing the suspension two to three times with the help of a micropipette. The resultant dispersion was deposited on quartz sample support for Total Reflection X-ray Fluorescence measurements. The Total Reflection X-ray Fluorescence spectrum of tagged and untagged inks could be clearly differentiated. In order to see the applicability of Total Reflection X-ray Fluorescence for quantitative determinations of rare earths and also to countercheck such determinations in ink samples, the amounts of rare earth in painted papers with single rare earth tagged inks were determined by digesting the painted paper in HNO3/HClO4, mixing this solution with the internal standard and recording their Total Reflection X-ray Fluorescence spectra after calibration of the instrument. The results thus obtained were compared with those obtained by Inductively Coupled Plasma Mass Spectrometry and were found in good agreement. The average precision of the Total Reflection X-ray Fluorescence determinations was 5.5% (1σ) and the average deviation of Total Reflection X-ray Fluorescence determined values with that of Inductively Coupled Plasma Mass Spectrometry was 7.3%. These studies have shown that Total Reflection X-ray Fluorescence offers a promising and potential application in forensic work of this nature.

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

    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.

  8. ISS Ammonia Leak Detection Through X-Ray Fluorescence

    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

  9. Child lead exposure determined from measurement of x-ray fluorescence of teeth in situ

    X-ray fluorescence from lead when irradiated by gamma rays from a Co-57 source was utilized to measure the lead concentration in children's teeth in situ. The sensitivity of the method was adequate to detect 15 ppM from a gamma ray exposure to the tooth approximately 1/10 the exposure of a routine dental x-ray examination. The tooth lead levels assayed using x-ray fluorescence correlated well with chemical assay techniques for both extracted permanent and shed primary teeth. Thirty children from the Children's Hospital of Philadelphia suspected of having elevated lead levels had tooth lead levels measured in situ determined using the x-ray fluorescent technique. The tooth lead concentration varied from a low of 16 ppM to a high of 56 ppM

  10. Combined use of hard X-ray phase contrast imaging and X-ray fluorescence microscopy for sub-cellular metal quantification.

    Kosior, Ewelina,; Bohic, Sylvain; Suhonen, Heikki; Ortega, Richard; Devès, Guillaume; Carmona, Asuncion; Marchi, Florence; Guillet, Jean Francois; Cloetens, Peter

    2012-01-01

    Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to obtain quantitative maps of the projected metal concentration in whole cells. The experiments were performed on freeze dried cells at the nano-imaging station ID22NI of the European Synchrotron Radiation Facility (ESRF). X-ray fluorescence analysis gives the areal mass of most major, minor and trace elements; it is validated using a biological standard of known composition. Quantitative phase contrast imag...

  11. Development of a portable system of X-ray fluorescence spectrometry

    This paper develops a compact and portable spectrometry system that will be used at the Laboratory of Applied Physics to the Biomedical and Environmental Sciences of the Institute of Physics/UERJ, Rio de Janeiro, Brazil. The laboratory both prepares the samples and develops the X-ray spectrometry techniques. The techniques of X-ray diffraction and fluorescence on various samples (biological, industrial and environmental) are used, attending to pos-graduation and graduation students, with multidisciplinary characteristics. The Mini-X system consists of X-ray mini tube MINI-X from Amptek with tungsten (W) target, and a compact spectrometer X123, also from Amptek that includes a detector, pre-amplifier, digital pulse processor, and multichannel. All the system is controlled by dedicated microprocessor. This work will present both a methodology for alignment and calibration of the system as far the first measurements performed using the X-ray fluorescence technique on standard samples. The multi elementary analysis by X-ray fluorescence (XRF) is based on the measurements of the characteristic X-ray intensity emitted by the chemical elements components of the samples when excited. Therefore, from the development of this compact and versatile system it will be possible to obtain the fluorescent intensities of the analysed samples at the Laboratory, not only at the research area but at the teaching area. Besides, new laboratory practices are being developed for the discipline of medical physics

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

    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.

  13. Cryo X-ray microscope with flat sample geometry for correlative fluorescence and nanoscale tomographic imaging.

    Schneider, Gerd; Guttmann, Peter; Rehbein, Stefan; Werner, Stephan; Follath, Rolf

    2012-02-01

    X-ray imaging offers a new 3-D view into cells. With its ability to penetrate whole hydrated cells it is ideally suited for pairing fluorescence light microscopy and nanoscale X-ray tomography. In this paper, we describe the X-ray optical set-up and the design of the cryo full-field transmission X-ray microscope (TXM) at the electron storage ring BESSY II. Compared to previous TXM set-ups with zone plate condenser monochromator, the new X-ray optical layout employs an undulator source, a spherical grating monochromator and an elliptically shaped glass capillary mirror as condenser. This set-up improves the spectral resolution by an order of magnitude. Furthermore, the partially coherent object illumination improves the contrast transfer of the microscope compared to incoherent conditions. With the new TXM, cells grown on flat support grids can be tilted perpendicular to the optical axis without any geometrical restrictions by the previously required pinhole for the zone plate monochromator close to the sample plane. We also developed an incorporated fluorescence light microscope which permits to record fluorescence, bright field and DIC images of cryogenic cells inside the TXM. For TXM tomography, imaging with multi-keV X-rays is a straightforward approach to increase the depth of focus. Under these conditions phase contrast imaging is necessary. For soft X-rays with shrinking depth of focus towards 10nm spatial resolution, thin optical sections through a thick specimen might be obtained by deconvolution X-ray microscopy. As alternative 3-D X-ray imaging techniques, the confocal cryo-STXM and the dual beam cryo-FIB/STXM with photoelectron detection are proposed. PMID:22273540

  14. X-ray Fluorescence Spectroscopy: the Potential of Astrophysics-developed Techniques

    Elvis, M.; Allen, B.; Hong, J.; Grindlay, J.; Kraft, R.; Binzel, R. P.; Masterton, R.

    2012-12-01

    X-ray fluorescence from the surface of airless bodies has been studied since the Apollo X-ray fluorescence experiment mapped parts of the lunar surface in 1971-1972. That experiment used a collimated proportional counter with a resolving power of ~1 and a beam size of ~1degree. Filters separated only Mg, Al and SI lines. We review progress in X-ray detectors and imaging for astrophysics and show how these advances enable much more powerful use of X-ray fluorescence for the study of airless bodies. Astrophysics X-ray instrumentation has developed enormously since 1972. Low noise, high quantum efficiency, X-ray CCDs have flown on ASCA, XMM-Newton, the Chandra X-ray Observatory, Swift and Suzaku, and are the workhorses of X-ray astronomy. They normally span 0.5 to ~8 keV with an energy resolution of ~100 eV. New developments in silicon based detectors, especially individual pixel addressable devices, such as CMOS detectors, can withstand many orders of magnitude more radiation than conventional CCDs before degradation. The capability of high read rates provides dynamic range and temporal resolution. Additionally, the rapid read rates minimize shot noise from thermal dark current and optical light. CMOS detectors can therefore run at warmer temperatures and with ultra-thin optical blocking filters. Thin OBFs mean near unity quantum efficiency below 1 keV, thus maximizing response at the C and O lines.such as CMOS detectors, promise advances. X-ray imaging has advanced similarly far. Two types of imager are now available: specular reflection and coded apertures. X-ray mirrors have been flown on the Einstein Observatory, XMM-Newton, Chandra and others. However, as X-ray reflection only occurs at small (~1degree) incidence angles, which then requires long focal lengths (meters), mirrors are not usually practical for planetary missions. Moreover the field of view of X-ray mirrors is comparable to the incident angle, so can only image relatively small regions. More useful

  15. Automatic energy dispersive x-ray fluorescence analysing apparatus

    The invention discloses a number of improvements for an energy dispersive X-ray analysis system having computer supervised data collection, display and processing. The systems with which the improved circuitry and methods may be used include a dual interlocking bus structure so that the analyzer and computer functions communicate directly with each other and the user has immediate keyboard control of both. Such a system normally includes a system base control, a control console and a display console. The portions of the system which have been improved include a new type of ratemeter which gives a voltage output proportional to the intensity of the energy window or windows under consideration, an output which is an absolute digital representation of the intensity count rate, circuitry for input multiplexing and multiple output voltage buffering of the ratemeter to accomodate multiple single channel signals, and a new dead time correction to enable meaningful single channel intensity data to be handled by the system. An extension of the ratemeter is also disclosed for use in conjunction with X-ray mapping, enabling enhancements to be made on mapping SCA data

  16. X-ray fluorescence analysis of erbium oxide/oxalate for rare earth impurities

    A method for the determination of Tb, Dy, Ho, Tm, Yb, Lu and Y oxides in Er2O3 is described. 450 mg sample in the oxalate form is mixed with 150 mg boric acid binding material and pressed into a 1.25 inch diameter pellet over a supporting pellet of boric acid. The sample is then irradiated by X-rays from a tungsten tube and the fluorescent X-rays are dispersed by a LiF (200) crystal in a Philips PW 1220 semiautomatic X-ray fluorescence spectrometer. The intensities of characteristic X-rays of the impurity elements are measured by a flow proportional counter for all elements except yttrium for which the intensities are measured by a scintillation counter. The lowest determination limit is 0.005% for all impurities except for Yb for which it is 0.01%. Calculations for theoretical detection limit are given. (author)

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

    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.

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

    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. Analysis of uranium ores by energy dispersive X-ray fluorescence

    The determination of uranium in ores by energy-dispersive X-ray fluorescence (XFA) is demonstrated for uranium ore samples of known content. For calibration silica gel standards are used. Matrix effects are corrected by measuring the Compton scattering peaks. The radionuclide 109Cd as well as a X-ray tube in combination with Mo or Sn as secondary targets are suited as X-ray sources. The mean relative deviation of the values found from the given values is 5%. (orig.)

  20. Investigation of flour by X-ray fluorescence trace element analysis

    The determination of the trace element content of some kinds of flour by X-ray fluorescence analysis is described. The samples are burned to ashes at 700 deg C then calibration standards are added to them. The X-ray spectra are evaluated by computer. The optimal thickness of samples for achieving suitable accuracy and short measuring time is investigated. The trace element content of some species of Hungarian wheat is determined and compared. (D.Gy.)

  1. A design of portable energy dispersive X-ray fluorescence analyzer

    A portable energy dispersive X-ray fluorescence analyzer (EDXRF) is designed. Excitation source is a small-caliber X-ray tube with Mo target. High-voltage power supply and filament supply is designed based on inverter technology. Semiconductor detectors is electric refrigerated, the qualities of the analyzer and the energy calibration curve are studied by the energy spectrum measurements for Cu, Zn, Ni, Pb, and the best range of elemental analysis is given by the theoretical analysis. (authors)

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

    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.

  3. Investigation of elemental distribution in lung samples by X-ray fluorescence microtomography

    X-Ray Fluorescence Microtomography (XRFCT) is a suitable technique to find elemental distributions in heterogeneous samples. While x-ray transmission microtomography provides information about the linear attenuation coefficient distribution, XRFCT allows one to map the most important elements in the sample. The x-ray fluorescence tomography is based on the use of the X-ray fluorescence emitted from the elements contained in a sample so as to give additional information to characterize the object under study. In this work a rat lung and two human lung tissue samples have been investigated in order to verify the efficiency of the system in determination of the internal distribution of detected elements in these kinds of samples and to compare the elemental distribution in the lung tissue of an old human and a fetus. The experiments were performed at the X-Ray Fluorescence beamline (XRF) of the Brazilian Synchrotron Light Source (LNLS), Campinas, Brazil. A white beam was used for the excitation of the elements and the fluorescence photons have been detected by a HPGe detector. All the tomographies have been reconstructed using a filtered-back projection algorithm. It was possible to visualize the distribution of high atomic number elements on both, artificial and tissues samples. It was compared the quantity of Zn, Cu and Fe for the lung human tissue samples and verify that these elements have a higher concentration on the fetus tissue sample than the adult tissue sample. (author)

  4. Comparison of different X-ray fluorescence analysis methods of total element content in soil

    Soil is a heterogeneous material and large variations in its chemical and physical nature can occur in a random samples collected in a small area of apparently similar land. Environmental analyses of soils call for rapid quantitative analysis techniques. X-ray fluorescence analysis has been used for many years and various sample preparation methods and analysis techniques have been used. Sample inhomogeneity is a very critical aspect of such a multielement analysis technique because rather small amount of soil generally are used for analyses. The aim of the current report is to compare different x-ray fluorescence techniques and sample preparation methods. Soil samples were collected from two different places in Botswana: Serowe and Gaborone.Three different x-ray fluorescence analysis techniques were used in the analysis of sandy soils. Two of them were energy-dispersive x-ray fluorescence spectrometers. The third was a total -reflection x-ray fluorescence spectrometer. A comparison shows that TXRF gives comparable results to EDXRF (second method). All results were within 10-15%. The conclusion is that TXRF is a suitable method not only for chemical speciation of soil, but also for the analysis of total fraction of elements

  5. Chemical Characterization of Nuclear Materials: Development a New Combined X-Ray Fluorescence and Raman Spectrometer

    New mobile analytical device based on combination of X-ray fluorescence and Raman spectrometer has been developed for prompt and quantitative characterization of chemical component from Al to U in nuclear waste or undeclared materials. The excitation source of the X-ray fluorescence spectrometer is an air-cooled X-ray tube with Ag transmission anode. For collection of secondary X-ray photons and data processing, a compact Amptek X-ray detector system is applied with silicon drift X-ray detector. The XRF system operates in confocal mode with focal volume around 1-4 mm3. Varying the geometrical position and orientation of the sample optional part of its surface can be analyzed. The Raman unit includes thermoelectrically cooled laser source having 500 mW power at wavelength 785 nm. In order to obtain spectral information from sample surface a reflection-type probe is connected by optical fibres to the Raman spectrometer. A mini focusing optics is set up to the sensor-fibre that provides the system to operate as confocal optical device in reflection mode. The XRF spectrometer with X-ray detector, Raman probe and X-ray tube are mechanically fixed and hermetically connected to an aluminium chamber, which can be optionally filled with helium. The chamber is mounted on a vertical stage that provides moving it to the sample surface. A new model and computer code have been developed for XRF quantitative analysis which describes the mathematical relationship between the concentration of sample elements and their characteristic X-ray intensities. For verification of the calculations standard reference alloy samples were measured. The results was in good agreement with certified concentrations in range of 0.001-100 w%. According to these numerical results this new method is successfully applicable for quick and non-destructive quantitative analysis of waste materials without using standard samples. (author)

  6. X-ray Fluorescence in Member States: Peru. Recent Activities in X ray Fluorescence Laboratory of the Peruvian Institute of Nuclear Energy - Peru

    Multielemental X ray fluorescence non-destructive analysis of the bony remainders attributed to the conqueror Mr. Francisco Pizarro for a study of contamination post-mortem, kind of diet and paleopathologies: The elementary chemical analysis of bones provides very important information that allows studying topics like post mortem contamination, diet and diverse paleopathologies that are observed based on the concentration of the elements identified. The bony remains of the conqueror Don Francisco Pizarro were analyzed by using an energy dispersive X ray fluorescence system with a Cd-109 source of 25 mCi. The spectra were analyzed by IAEA-AXIL-QXAS software. The quantification was carried out with the option of simple quantitative analysis, with the method of elemental sensitivity. The presence of the elements: Ca, Fe, Cu, Zn, Sr and Pb was mainly observed confirming a vegetarian diet and the presence of the surrounding materials. Archaeometric study of metallic pieces from Museo Inka - Universidad Nacional San Antonio Abad from Cusco, Peru: An archaeometric study of metallic pieces, pins (tupus), has been presented. These pieces were found in excavation of Sacsayhuaman strength, Cusco - Peru, from the Inca culture. Metallographic, X ray diffraction and X ray fluorescence analysis of these pieces reveal that pins presents neither the same technology of preparation nor the same elemental composition. All the pieces include copper, as major element, combined with As or Pb. Some of them have a superficial layer of gold and/or silver. Ornamental Nasca ceramics pigments identification by X ray diffraction and X ray fluorescence analysis. The Nasca culture was developed in the southern coast of Peru (100 BC to 650 AD), during the Early Intermediate Period. The most significant remain of the Nasca Culture is the fine polychrome pottery. The goal of this work is to identify the pigments used in 54 pottery fragments recovered nearby Palpa and Cahuachi by using XRF and XRD

  7. Surface characterization of selected polymer thin films by total-reflection x-ray fluorescence spectroscopy and x-ray reflectivity

    Development of available x-ray characterizations tools for grazing incidence techniques was done to be able to probe nano-size thin films. Alignment of a Philips x-ray powder diffractometer was improved to let it perform as an x-ray reflectometer. X-ray reflectometry was coupled with total-reflection x-ray fluorescence spectroscopy. Evaluation of the performance of this grazing incidence techniques was done by preparing polymer thin films of carboxymethylcellulose, carrageenan and polyvinylpyrrolidone (PVP). The thickness of the films were varied by varying the process parameters such as concentration, spin speed and spin time. Angle-dispersive total-reflection x-ray fluorescence spectroscopy profiles of three films showed film formation only in carrageenan and PVP. For both carrageenan and PVP, an increase in concentration yielded a corresponding increase in intensity of the fluorescent or scattered peaks. XRR profiles of carrageenan thin films yielded a mean value for the critical angle close to quartz substrate. Thickness measurements of the prepared carrageenan thin films showed that concentration was the main determinant for final film thickness over the other process parameters. Sulfur fluorescent intensity derived from the TXRF measurement showed a linear relationship with the measured thickness by XRR. For PVP, measured critical angle is lower than quartz. Poor adhesion of the polymer onto the substrate yielded a limited number of thickness measurements made from the XRR profiles. (Author)

  8. X-ray fluorescence in IAEA Member States: Peru

    The application of the XRF technique performed in our laboratories in the field of archaeology began in 1994. It started with the analysis of different samples, as an incisive tooth, a fragment of occipital, a rib fragment, a segment of dorsal vertebra and small glasses found in the internal surface of a Nazca Culture mummy. In the paleopathological study performed by Dr. Guido Lombardi a 109Cd excitation source and an X ray spectrometry system were used. The elemental concentrations of Ca, Fe, Zn, and Sr were determined for the paleonutricion studies by using the relationships of Zn/Ca and Sr/Ca. The XRF technique also contributed to the mycobacterium tuberculosis detection in a mummy, supplementing other non destructive tests carried out previously. In recent years, 29 right clavicles belonging to mature individuals were analyzed out of 143 found in the Villa El Salvador area. Sr and Zn concentrations were used to determine the relative proportion of vegetable and animal foods in the population's diet under study. It was concluded that the old residents of this town manifested an omnivorous feeding with carnivorous tendency, due to consumption of products of marine origin. Ceramics have also been analyzed to determine the chemical composition of the paste which was used in the production process. 39 fragments of ceramic from the place called Lomo de Corvina of Villa El Salvador, low valley in Lurin town were analyzed. The analysis of these samples was focused on quantitative determination of Ti, Fe, Rb, Sr, Y, Zr and Nb, to complement the results obtained by neutron activation analysis. Identification of the pigments used for production of art objects is of great importance for its characterization, authentication and/or restoration. For this reason, we are currently working on identification of pigments used in the decoration of archaeological ceramics. This work started from construction of a portable XRF spectrometer based on a small size, low power X ray tube

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

    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.

  10. An engineering development of fluoroscopic X-ray medical equipment based-on fluorescent screen

    Fluoroscopic x-ray medical equipment uses fluorescent screen to capture structural image of organs. Unlike conventional x-ray equipment which uses film, in the fluoroscopic x-ray, the resulting image is visualized on the fluorescent screen and directly observed by physicians in the patients' rooms. In this study, we developed an image capture system that transforms the image on the fluorescent screen into digital data, which is then transferred to computer for visualization and further processing. By using this system, the observation of the resulting image can be done on a computer that is placed in the control room. The image can also be stored easily and at low cost compared to conventional film. The experiment shows that the system could be used to capture image of the object. However, its quality needs to be improved. In the future, the system will be modified and tested with different types of cameras to obtain better results. (author)

  11. Analysis of eight argonne premium coal samples by X-ray fluorescence spectrometry

    Evans, J.R.; Sellers, G.A.; Johnson, R.G.; Vivit, D.V.; Kent, J.

    1990-01-01

    X-ray fluorescence spectrometric methods were used in the analysis of eight Argonne Premium Coal Samples. Trace elements (Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, La, and Ce) in coal ash were determined by energy-dispersive X-ray fluorescence spectrometry; major elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, and Fe) in coal ash and trace elements (Cl and P) in whole coal were determined by wavelength-dispersive X-ray fluorescence spectrometry. The results of this study will be used in a geochemical database compiled for these materials from various analytical techniques. The experimental XRF methods and procedures used to determine these major and trace elements are described.

  12. Demonstration of x-ray fluorescence imaging of a high-energy-density plasma

    Experiments at the Trident Laser Facility have successfully demonstrated the use of x-ray fluorescence imaging (XRFI) to diagnose shocked carbonized resorcinol formaldehyde (CRF) foams doped with Ti. One laser beam created a shock wave in the doped foam. A second laser beam produced a flux of vanadium He-α x-rays, which in turn induced Ti K-shell fluorescence within the foam. Spectrally resolved 1D imaging of the x-ray fluorescence provided shock location and compression measurements. Additionally, experiments using a collimator demonstrated that one can probe specific regions within a target. These results show that XRFI is a capable alternative to path-integrated measurements for diagnosing hydrodynamic experiments at high energy density

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

    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

  14. Portable total reflection x-ray fluorescence spectrometer for ultra trace elemental determination

    It has been believed that the use of high power monochromatic incident X-rays such as monochromatic synchrotron radiation is essential for improving detection limits in the total reflection X-ray fluorescence (TXRF) analysis. On the other hand, we have reported that polychromatic excitation improves detection limits in the TXRF analysis compared with monochromatic excitation. We have developed portable TXRF spectrometers using polychromatic X-rays from a low power (several watts) X-ray tube, and a 10 pg (10-11 g) detection limit is achieved with the weak polychromatic X-rays. This low detection limit is obtained using the following methods with polychromatic excitation: (1) measuring smaller amounts of a sample, (2) optimization of a tube voltage, and tube current, (3) optimization of a glancing angle, (4) the use of an appropriate target material of an X-ray tube, and (5) the use of an X-ray waveguide. In the present paper, experimental set-up of the present portable spectrometer and the change of detection sensitivity by changing experimental conditions such as tube voltage are explained. Applications to trace elemental analysis of urine and pigments are also shown. (author)

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

    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.

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

    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.

  17. Simultaneous determination of actinides by x-ray fluorescence spectrometry

    The x-ray spectrometric simultaneous determination of uranium and plutonium in simulated Purex Process solutions is described. The method is accomplished by intensity measurements of the L α sub(1) lines. The thin film technique for sample preparation and thorium as an internal standard had been used. An evaporation technique had been also tested for low concentration uranium solutions. In the measurement range 0,05 - 130 U g/L, 0,5 - 20 Pu g/L linear calibration curves were effected. The standard deviation in the concentration range 10 to 130 g/L was 3,5%, 4% in the 1 to 10 g/L and 13% in 0,05 to 1 g/L for uranium determination and 4% for plutonium determination in the range of 1 to 20 g/L. The sensitivity of the method was about 3,62 μg to U and 3,95 μg to Pu. Uranium and plutonium do not reciprocally interfere with one another until U/Pu ≅ 90 m/m. The fission product as interfering elements were also verified. Finally, uranium and plutonium were determined in simulated Purex Process solutions within the requested accuracy for control method. (author)

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

    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.

  19. Sc Κα and Κβ X-ray fluorescence spectra

    X-ray fluorescence spectrometry is now one of the most powerful tools for quantitative elemental analysis as well as chemical state analysis of new materials. A complete theoretical understanding of the X-ray emission process still does not exist even after the century following the discovery of X-rays. The major motivation of this study is to clarify the origin of the chemical effects of X-ray emission lines so as to better utilize these chemical effects for chemical state analysis or characterization. The origins of the chemical effects on the XRF satellites of Sc are discussed and a systematic study on the chemical shifts of Sc Kα1 and Kβ1.3 lines of scandium metal and various scandium compounds is presented. (author)

  20. Oscillating dipole model for the X-ray standing wave enhanced fluorescence in periodic multilayers

    André, Jean-Michel; Le Guen, Karine; Jonnard, Philippe

    2013-01-01

    International audience Periodic multilayers give rise to enhanced X-ray fluorescence when a regime of standing waves occurs within the structure. This regime may concern the primary radiation used to induce the fluorescence, the secondary radiation of fluorescence or both of them. Until now, existing models only dealt with standing wave regime of primary radiation. We present a theoretical approach based on the oscillating dipole model and the coupled-wave theory that can treat efficiently...

  1. Langmuir monolayers on water surface investigated by X-ray total reflection fluorescence

    Langmuir monolayers of metal-rich phthalocyanines (Pc) and phospholipid at air/water interface have been studied by X-ray total reflection fluorescence at SR beam line ID 10B (ESRF). Experimental fluorescence angular dependences from 'heavy' ions of a monolayer alone on water surface modulated by evanescent wave/X-ray standing wave pattern have been detected for the first time, are in good agreement with calculations and provide information about the position of metal ions in organic molecule with respect to water surface

  2. Langmuir monolayers on water surface investigated by X-ray total reflection fluorescence

    Zheludeva, S.I.; Novikova, N.N.; Konovalov, O.V.; Kovalchuk, M.V.; Stepina, N.D.; Tereschenko, E.Yu

    2003-10-15

    Langmuir monolayers of metal-rich phthalocyanines (Pc) and phospholipid at air/water interface have been studied by X-ray total reflection fluorescence at SR beam line ID 10B (ESRF). Experimental fluorescence angular dependences from 'heavy' ions of a monolayer alone on water surface modulated by evanescent wave/X-ray standing wave pattern have been detected for the first time, are in good agreement with calculations and provide information about the position of metal ions in organic molecule with respect to water surface.

  3. X-ray fluorescence analysis and optical emission spectrometry of an roman mirror from Tomis, Romania

    The miscellaneous population of Roman Empire, their diverse cultural tradition, their ability to assimilate the roman civilization spirits, had determined a permanent reassessment superimposed upon the roman contribution. Analysis was undertaken using optical emission spectrometry and non-destructive X-ray fluorescence. X-ray fluorescence analysis is a well-established method and is often used in archaeometry and other work dealing with valuable objects pertaining to the history of art and civilization. Roman mirror analysed has been found not to be made of speculum (a high tin bronze). (authors)

  4. Grazing-emission X-ray fluorescence spectrometry: principles and applications

    Bokx, P.K. de; Kok, C.; Bailleul, A.; Wiener, G.; Urbach, H.P. [Philips Research Labs., Eindhoven (Netherlands)

    1997-06-20

    In grazing emission X-ray fluorescence spectrometry (GEXRF), the sample is irradiated at approximately normal incidence, and only that part of fluorescence radiation is detected that is emitted at grazing angles. This configuration allows the use of wavelength-dispersive detection. This type of detection has the advantages of substantially better energy resolution at longer wavelengths (light elements, L and M lines of heavier elements) and a much larger dynamic range than the energy-dispersive detectors currently used in grazing X-ray techniques. Typical examples are presented of applications that are made possible by this new technique. (Author).

  5. Quantification estimate methods for synchrotron radiation X-ray fluorescence spectroscopy

    Bewer, Brian, E-mail: brian.bewer@lightsource.ca

    2015-03-15

    Synchrotron radiation X-ray fluorescence spectroscopy is a method which allows low elemental concentrations to be measured within a sample. To maintain biological or medical relevance increased importance is being placed on quantifying these in situ localized elemental concentrations. For third generation synchrotron light sources, which have the potential for high sample throughput, a rapid method of obtaining a quantification estimate is needed. Non-destructive transmission and surface analysis techniques for first transition metals, or elements of higher atomic number, using reference standards are examined for different sample property regimes to elucidate methods of quantitative synchrotron radiation X-ray fluorescence spectroscopy.

  6. Influence of crystallinity and polymer matrix on additive quantification by X-ray fluorescence

    Additives are added to polymers during their synthesis, processing or when mixing to other materials and they play an important role on the polymer properties. The objective of this work is to study the influence of the polymer matrix and crystallinity on silicon and other additives quantification by X-ray fluorescence. Initial results showed that X-ray fluorescence can be used to characterize and quantify silicon in polypropylene and in high density polyethylene but it did not show reliable results to linear low density polyethylene and low density polyethylene. (author)

  7. X-RAY DIFFRACTION AND X-RAY FLUORESCENCE ANALYSIS OF POTTERY SHARDS FROM NEW ARCHAEOLOGICAL SURVEY IN SOUTH REGION OF SISTAN, IRAN

    Sarhaddi-Dadian, Hossein; Ramli, Zuliskandar; Shuhaimi, Nik Hassan; Rahman, Nik Abdul; Mehrafarin, Reza

    2015-01-01

    The aim of this study is to determine whether pottery shards from new archaeological survey in south region of Sistan are locally made or imported. Many artefacts especially pottery shards have been found during the archaeological survey. These pottery shards are variable in color; from buff, grey, black, and red. The analytical techniques involved X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD), that were applied to determine the major and trace elements and also the mineral content of ...

  8. Development of confocal 3D X-ray fluorescence instrument and its applications to micro depth profiling

    We have developed a confocal micro X-ray fluorescence instrument. Two independent X-ray tubes of Mo and Cr targets were installed to this instrument. Two polycapillary full X-ray lenses were attached to two X-ray tubes, and a polycapillary half X-ray lens was also attached to the X-ray detector (silicon drift detector, SDD). Finally, three focus spots of three lenses were adjusted at a common position. By using this confocal micro X-ray fluorescence instrument, depth profiling for layered samples were performed. It was found that depth resolution depended on energy of X-ray fluorescence that was measured. In addition, X-ray elemental maps were determined at different depths for an agar sample including metal fragments of Cu, Ti and Au. The elemental maps showed actual distributions of metal fragments in the agar, indicating that the confocal micro X-ray fluorescence is a feasible technique for non-destructive depth analysis and 3D X-ray fluorescence analysis. (author)

  9. X-ray fluorescence in IAEA Member States: Croatia

    A beam line attached to the Tandem Van de Graaff accelerator at the Rudjer Boskovic Institute (RBI) in Zagreb, Croatia, has been installed by the IAEA. Seibersdorf. The beam line consists of a vacuum chamber equipped with Si(Li) detector for PIXE spectroscopy positioned at the 135 deg. port, as well as with a particle detector for RBS positioned in the chamber at the 165 degree scattering angle. Recently in 2005, a new 1.0 MV Tandetron accelerator has been installed, enabling use of IAEA beam line with any of two existing accelerators. Homogeneity tests performed by PIXE included tests at microscopic level using RBI nuclear microprobe. Several joint intercomparison tests including two with NIST showed excellent capabilities of the beam line PIXE quantification procedure. Several run sessions were dedicated for PIXE studies a series of archeometry samples of ceramics and polychrome pigments, different geological samples, as well as more recently series of timber species. RBS technique was used for analysis of multilayered thin film technological samples. The use of RBS for the analysis of matrix composition was important for testing reliability of PIXE and XRF quantification procedure based on fundamental parameters. In collaboration with Seibersdorf Laboratories, important improvement has been obtained in development of universal multiparameter data acquisition hardware and software. The software SPECTOR that can control different hardware for data acquisition has, in addition to independent acquisition of spectra from various detectors, the possibility to control sample positioning, as well as microbeam scanning (for proton microbeam at IRB) and sample stage scanning and control (for X ray microbeam at Seibersdorf). Quality control procedures were started to be implemented as well. Operation, measurement and quantification standard operation procedures (SOPs) have been completed

  10. X-ray fluorescence in IAEA Member States: Sri Lanka

    An ED-XRF facility was established in the analytical laboratory of the Atomic Energy Authority of Sri Lanka in 2001 under the technical assistance received through a IAEA TC project. The facility comprises of a X ray tube (Rich - Seifert), a sample holder with secondary target assembly and a Si (Li) detector. The laboratory has also got the necessary facilities to analyze water samples by co-precipitating technique using APDC. Our XRF laboratory has already established analytical procedures to use emission transmission methods (AXIl-QAES, P. Kump), back-scatter fundamental parameter method (QXAS-BFP), APDC co-precipitation method and thin and thick sample analysis method. Selected activities carried out by the XRF Laboratory are: Research study on heavy metal concentration levels in crow feathers collected from different environments and in industrial effluents released to a main water body (i.e the Kelani River); Research study on hyper accumulating capacity of flora in Ussangoda area (Serpentine mineral deposited area); Study on the possibility of removing heavy metals in liquid waste by bricks (low cost waste water treatment method); Study on heavy metal contamination in soil collected from Tsunami affected areas; Elemental analysis of air particulate matter to identify pollutants and pollution sources; Provision of analytical services to archaeological studies; Alloy analysis for technical evaluations. In Sri Lanka, there is a rising demand for this analytical service as it can provide the customer relatively fast and reliable results at low cost. AEA has decided to upgrade the existing facility to TXRF through the IAEA technical assistance to meet the demand for the services to analyse water and other liquid samples. In addition, Quality Assurance and Quality control procedures have been implemented for validation of analytical methods and check of accuracy of analytical results obtained

  11. Application of x-ray fluorescence to the measurement of additives in paper

    Titanium dioxide content in paper was measured by x-ray fluorescence analysis using an 55Fe source and an x-ray proportional counter to determine the feasibility of an on-line instrument. X-ray calibration curves for 60- and 100-g/m2 paper samples were obtained using neutron activation to measure the titanium dioxide concentration. The predictions of a simple model were in good agreement with the experimental calibration curves. The measurements and calculations were extended to investigate the effects of clay and moisture. The presence of clay has a significant effect on the x-ray fluorescence determination of the titanium dioxide concentration; however, this can be well accounted for by the model. The calculations indicated that the effect of typical moisture levels on the titanium dioxide determination was small and can be ignored. It is not possible to measure the clay content by x-ray fluorescence; however, preliminary results for the determination of calcium carbonate concentration are promising

  12. Influence of X-ray tube spectral distribution on uncertainty of calculated fluorescent radiation intensity

    The relative radiation intensity (Ri) defined as fluorescent radiation intensity of analyte in specimen to fluorescent radiation intensity of pure element or compound, e.g., oxide is used in calculation in both fundamental parameter methods and in theoretical influence coefficient algorithms. Accuracy of calculated Ri is determined by uncertainties of atomic parameters, spectrometer geometry and also by X-ray tube spectral distribution. This paper presents the differences between Ri calculated using experimental and theoretical X-ray tube spectra evaluated by three different algorithms proposed by Pella et al., Ebel, and Finkelshtein-Pavlova. The calculations are performed for the most common targets, i.e., Cr, Mo, Rh and W. In this study, Ri is calculated for V, Cr, Mn, Fe, Co, Ni, Cu and Mo in steels as an example. The differences between Ri calculated using different X-ray tube spectrum algorithms are presented when pure element standard, multielement standard similar to the analyzed material and one pure element standard for all analytes is used in X-ray fluorescence analysis. The differences between Ri for intermediate-thickness samples (and also for thin films) and for X-ray tube, which ran for many hours, are also evaluated

  13. NEW CORRECTION PROCEDURE FOR X-RAY SPECTROSCOPIC FLUORESCENCE DATA: SIMULATIONS AND EXPERIMENT.

    ABLETT, J.M.; WOICIK, J.C.; KAO, C.C.

    2004-08-02

    X-ray fluorescence spectroscopy is a widely used method for determining the electronic configuration and local structure of dilute species with high sensitivity. In the dilute limit, and for thin films, the X-ray fluorescence signal is directly proportional to the atomic sub-shell absorption coefficient. However, for concentrated samples, the well-documented self-absorption effect often leads to the severe suppression of XANES (X-ray Absorption Near-Edge Structure) and EXAFS (Extended X-ray Absorption Fine-Structure) amplitudes. Thus to recover the real value of the sub-shell absorption coefficient, it is important to apply correction procedures to the measured fluorescence spectra. In this paper, we describe a new straightforward method to correct for self-absorption effects (the difference in the measured fluorescence signal compared to that of the true sub-shell photoabsorption coefficient) in XANES and EXAFS fluorescence measurements. Using a variety of sample and detector configurations, this method is used to extract the sub-shell absorption coefficient on elemental nickel and thick single-crystals of Gd{sub 3}Ga{sub 5}O{sub 12} and LaAlO{sub 3}.

  14. Sediment U, Th, K content analyzed using X-ray fluorescence spectrometry for ESR dating samples

    The accurate measurement of dose rate is the key issues to obtain reliable ESR age. In this article, we used X-ray fluorescence spectrometry to determine the U, Th, K content of the fluvial sediments. And the standard working curves were established using the national rock reference material. Setting the lower X-ray power and the matrix effect, U, Th, K content in the fluvial sediment were investigated. The results show that the method recovery rate of U and Th is less than 15%. Comparing with the measurement data from the α-counting and Atomic Spectrometry analysis, the dose rate difference is less than 5%. It shows that the X-ray fluorescence spectrometry method can fit for the requirement for obtaining the U, Th, K content of fluvial sediment for ESR dating. (authors)

  15. Total-reflection X-ray fluorescence analysis of Austrian wine

    The concentration of major, minor and trace elements in Austrian wine was determined by total-reflection X-ray fluorescence using gallium as internal standard. A multi-elemental analysis was possible by pipetting 6 μl of wine directly on the reflector and drying. Total-reflection X-ray fluorescence analysis was performed with Atomika EXTRA II A (Cameca) X-rays from a Mo tube with a high-energy cut-off at 20 keV in total-reflection geometry. The results showed that it was possible to identify only by the elemental analysis as fingerprint the vineyards and year of vintage among 11 different wines

  16. Optimizing the flotation technologies by means of on-stream X-ray fluorescence analysis

    X-ray fluorescence analysis has been successfully applied for more than 20 years in different instrumental configuration for the purpose of optimizing and controlling the ore processing technological processes performed by flotation. The paper presents a recent achievement provided with an on-stream X-ray fluorescence analytical system implemented at the Baia Mare Flotation Center within a cooperation project between ICPM Baia Mare and the 'Tvetmetavtomatika' Institute in Moscow - Russia. The paper includes the construction of the system, the operating characteristics of the 'SRM-13' type X-ray spectrometers, the mathematical model used for their calibration for analyzing the pulp samples, required sensitivity corrections and accuracy and the resulting technical-economical effects as well. (Author)

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

    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

  18. Ray-tracing of a Real-Time X-Ray Fluorescence Microscope

    The author is doing the conceptual design of the Real-time X-ray Fluorescence Microscope (R-XRFM) which can perform elemental mapping by X-ray fluorescence without scanning the sample. Doubly curved crystal of a Johansson type monochromator or a Johann type monochromator will be used as a point-to-point focus monochromator in R-XRFM and the performances in each case were evaluated by simulation calculation using ray-tracing method. From the result of the calculation in conditions of a 60 mm diameter α-quartz crystal monochromator, a 300 mm radius Rowland circle, and an X-ray fluorescence wavelength of Al Kα1, in both cases of the Johansson type and in case of the Johann type 40 mm in width, it was found that the angular resolution is 0.010deg, and there is a possibility that R-XRFM can perform elemental mapping identifying the differences in the fluorescent X-ray wavelength of the aluminum due to the difference in the coordination number. In the case of Johansson type, it was found that the X-rays converge on the detector surface with the spatial resolution < 0.001-1.3 μm from the analyzing area of 0-50 μm square, and with the spatial resolution 1.3-2.5 μm from the analyzing area of 50-100 μm square. In the case of Johann type 40 mm in width, it was found that the X-rays converge on a detector surface with the spatial resolution 1.5-3.7 μm from the analyzing area of 0-100 μm square. (author)

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

    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

  20. Mobile low power total reflexion x-ray fluorescence spectrometer with pg-detection-limit

    Full text: Total reflexion x-ray fluorescence (TXRF) spectrometry is an efficient tool in trace element analysis. Conventional laboratory spectrometers can achieve detection limits in the pg-range. Unfortunately high power X-ray tubes (i.e. some kW) and LN2-cooled Si(Li)-detectors are sometimes not applicable within mobile TXRF-spectrometers. Therefore a portable device for TXRF (PicoTAXPS) has been developed and the latest results will be presented. This device is a very compact combination of an air-cooled low power X-ray tube (Mo-anode, 40W) a Peltier-cooled PlN-diode detector and a high quality flat primary Ni/C X-ray mirror (2t= 7.84 nm, N100, R> 80%). The background radiation is reduced by means of this particular mirror. That way the achievable detection limits are comparable with conventional 1.5 kW TXRF- spectrometers. The characteristic parameters of X-ray source, detector and Ni/C mirror will be presented. Additionally, the performance of this portable TXRF-system will be demonstrated by selected examples. Copyright (1999) Australian X-ray Analytical Association Inc

  1. Formation of binary and ternary metal deposits on glass-ceramic carbon electrode surfaces: electron-probe X-ray microanalysis, total-reflection X-ray fluorescence analysis, X-ray photoelectron spectroscopy and scanning electron microscopy study

    The features of the formation of binary and ternary alloys during the electrochemical deposition and co-deposition of copper, cadmium and lead from aqueous solutions on disc glass-ceramic carbon electrode surfaces were studied by electron-probe X-ray microanalysis, total-reflection X-ray fluorescence analysis, X-ray photoelectron spectroscopy and scanning electron microscopy. The macroscopic properties of electrodeposits such as morphology, lateral distribution of the elements along the disc electrode surface and depth distribution of the elements in the electrodeposit bulk were established. The mechanisms of metal nucleation and growth of thin films of electrodeposits were discussed

  2. Some applications of x-ray fluorescence spectrography to the determination of uranium and thorium

    Several methods for the determination of uranium and thorium by X-ray fluorescence spectrography are described. In pure solutions the sensitivity for these elements is 5-10 ppm. For solutions containing gross concentrations of impurities, strontium is added as an internal standard. Precision and accuracy of the determinations are about 1% when working in the optimum concentration range. (author)

  3. X-ray fluorescence method in analyzing forest fire emission elements

    Composition of aerosols from large taiga forest fires was investigated using an X-ray fluorescence method that involves excitation of the characteristic spectrum by synchrotron radiation. Emissions were sampled directly from the convection column with the help of various instruments (including an impactor) mounted on a helicopter. We compared the results of the study with literature data

  4. Fast, versatile x-ray fluorescence method for measuring tin in impregnated wood

    Drabæk, I.; Christensen, Leif Højslet

    1985-01-01

    The present paper describes an energy-dispersive x-ray fluorescence method for measuring tin in bis(tri-n-butyl)tin-oxide impregnated wood. The proposed method is of the backscatter/fundamental parameter type. Its versatility, precision, and accuracy is demonstrated by analyses of eleven samples of...

  5. Determination of rhenium in molybdenite by X-ray fluorescence. A combined chemical-spectrometric technique

    Solt, M.W.; Wahlberg, J.S.; Myers, A.T.

    1969-01-01

    Rhenium in molybdenite is separated from molybdenum by distillation of rhenium heptoxide from a perchloric-sulphuric acid mixture. It is concentrated by precipitation of the sulphide and then determined by X-ray fluorescence. From 3 to 1000 ??g of rhenium can be measured with a precision generally within 2%. The procedure tolerates larger amounts of molybdenum than the usual colorimetric methods. ?? 1969.

  6. Trace element analysis of red beet and its cell cultures by x-ray fluorescence method

    Cell cultures from red beet root and beet sprout were analysed by isotope excited energy-dispersive X-ray fluorescence method. The excitation source was 125I. High zinc ion concentrations were found in cell cultures together with high histidine content. (author)

  7. Energy-Dispersive X-Ray Fluorescence Spectrometry: A Long Overdue Addition to the Chemistry Curriculum

    Palmer, Peter T.

    2011-01-01

    Portable Energy-Dispersive X-Ray Fluorescence (XRF) analyzers have undergone significant improvements over the past decade. Salient advantages of XRF for elemental analysis include minimal sample preparation, multielement analysis capabilities, detection limits in the low parts per million (ppm) range, and analysis times on the order of 1 min.…

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

    The present 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

  9. Confirmation of molecular formulas of metallic complexes through X-ray fluorescence quantitative analysis

    X-ray fluorescence spectrophotometry was employed to determined the metal content in a series of five transition element complexes (Mn, Ti, Zn, V). The results confirmed the molecular formulas of these complexes, already proposed on the basis of elemental microanalysis, solution condutimetry and other analytical methods. (C.L.B.)

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

    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.

  11. Preliminary experiment of fluorescent X-ray computed tomography to detect dual agents for biological study.

    Yu, Q; Takeda, T; Yuasa, T; Hasegawa, Y; Wu, J; Thet-Thet-Lwin; Hyodo, K; Dilmanian, F A; Itai, Y; Akatsuka, T

    2001-05-01

    The simultaneous observation of various information, such as blood flow, tissue metabolism and distribution of receptors, is quite important in order to understand the functional state of biomedical objects. The simultaneous detectability of contrast agents by fluorescent X-ray computed tomography (FXCT) with synchrotron radiation is examined in this study. The system consisted of a silicon (111) double-crystal monochromator, an X-ray slit system, a scanning table, a PIN diode, a highly purified germanium detector and an X-ray charge-coupled device (CCD) camera. The monochromatic X-ray beam energy was adjusted to 37.0 keV and collimated into a pencil beam of 1 x 1 mm. The fluorescent spectra of the K alpha lines for iodine and xenon were detected simultaneously. FXCT could image the distribution of both iodine and xenon agents in a phantom clearly and the contrast ratio was significantly better than that of transmission X-ray computed tomography images. PMID:11486409

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

    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.

  13. X-ray Fluorescence in Member States: Spain. Activities at the Laboratory of X ray Analytical Applications (LARX)

    1. Determination of Metal Residues in Active Pharmaceutical Ingredients According to Current Legislation by Using XRF Spectrometry. Safety and efficacy of pharmaceuticals are two fundamental issues of importance in drug therapy. Therefore, the determination of potential impurities in different stages of the manufacturing processes, and especially in the final product, is necessary to prevent potential risk to human health. Metals can be introduced in the active pharmaceutical ingredients (API) through different sources (raw materials, reagents, catalysts, reactors, etc) and, consequently, they are potential impurities in the drug substances and are routinely monitored. 2. Application of XRF Spectrometry in Phytoremediation Activities Around Mining Areas. In the last decade, the use of plants for the stabilization (phytostabilization) and clean-up (phytoremediation) of metal contaminated environments has gained popularity among government agencies worldwide, as alternate or complementary cost-effective non-invasive technology to the engineering based remediation methods. In view of the considerable number of analyses necessary in phytoremediation and plant biology studies, it is important that the analytical procedures used for elemental determination in plant tissues should be fast and cheap, with simple sample preparation, and of adequate accuracy and precision. Last years, we have developed several analytical methodologies, using diverse configurations of XRF spectrometers (EDXRF, WDXRF, HE-P-EDXRF), to determine elemental composition of vegetation grown in mining areas. Recently, in collaboration with a research group from the Department of Chemical Engineering, Agriculture and Food Technology of the University of Girona (Spain), we have studied the possibilities and limitations of a low-cost benchtop energy dispersive X ray fluorescence (EDXRF) instrument to be employed as analytical technique for studying the potential use of sunflowers (Helianthus annuus) for

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

    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.

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

    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 Kα and Kβ 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

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

    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.

  17. Improving x-ray fluorescence signal for benchtop polychromatic cone-beam x-ray fluorescence computed tomography by incident x-ray spectrum optimization: A Monte Carlo study

    Manohar, Nivedh [Nuclear/Radiological Engineering and Medical Physics Programs, Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Jones, Bernard L. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Cho, Sang Hyun, E-mail: scho@mdanderson.org [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2014-10-15

    Purpose: To develop an accurate and comprehensive Monte Carlo (MC) model of an experimental benchtop polychromatic cone-beam x-ray fluorescence computed tomography (XFCT) setup and apply this MC model to optimize incident x-ray spectrum for improving production/detection of x-ray fluorescence photons from gold nanoparticles (GNPs). Methods: A detailed MC model, based on an experimental XFCT system, was created using the Monte Carlo N-Particle (MCNP) transport code. The model was validated by comparing MC results including x-ray fluorescence (XRF) and scatter photon spectra with measured data obtained under identical conditions using 105 kVp cone-beam x-rays filtered by either 1 mm of lead (Pb) or 0.9 mm of tin (Sn). After validation, the model was used to investigate the effects of additional filtration of the incident beam with Pb and Sn. Supplementary incident x-ray spectra, representing heavier filtration (Pb: 2 and 3 mm; Sn: 1, 2, and 3 mm) were computationally generated and used with the model to obtain XRF/scatter spectra. Quasimonochromatic incident x-ray spectra (81, 85, 90, 95, and 100 keV with 10 keV full width at half maximum) were also investigated to determine the ideal energy for distinguishing gold XRF signal from the scatter background. Fluorescence signal-to-dose ratio (FSDR) and fluorescence-normalized scan time (FNST) were used as metrics to assess results. Results: Calculated XRF/scatter spectra for 1-mm Pb and 0.9-mm Sn filters matched (r ≥ 0.996) experimental measurements. Calculated spectra representing additional filtration for both filter materials showed that the spectral hardening improved the FSDR at the expense of requiring a much longer FNST. In general, using Sn instead of Pb, at a given filter thickness, allowed an increase of up to 20% in FSDR, more prominent gold XRF peaks, and up to an order of magnitude decrease in FNST. Simulations using quasimonochromatic spectra suggested that increasing source x-ray energy, in the

  18. Improving x-ray fluorescence signal for benchtop polychromatic cone-beam x-ray fluorescence computed tomography by incident x-ray spectrum optimization: A Monte Carlo study

    Purpose: To develop an accurate and comprehensive Monte Carlo (MC) model of an experimental benchtop polychromatic cone-beam x-ray fluorescence computed tomography (XFCT) setup and apply this MC model to optimize incident x-ray spectrum for improving production/detection of x-ray fluorescence photons from gold nanoparticles (GNPs). Methods: A detailed MC model, based on an experimental XFCT system, was created using the Monte Carlo N-Particle (MCNP) transport code. The model was validated by comparing MC results including x-ray fluorescence (XRF) and scatter photon spectra with measured data obtained under identical conditions using 105 kVp cone-beam x-rays filtered by either 1 mm of lead (Pb) or 0.9 mm of tin (Sn). After validation, the model was used to investigate the effects of additional filtration of the incident beam with Pb and Sn. Supplementary incident x-ray spectra, representing heavier filtration (Pb: 2 and 3 mm; Sn: 1, 2, and 3 mm) were computationally generated and used with the model to obtain XRF/scatter spectra. Quasimonochromatic incident x-ray spectra (81, 85, 90, 95, and 100 keV with 10 keV full width at half maximum) were also investigated to determine the ideal energy for distinguishing gold XRF signal from the scatter background. Fluorescence signal-to-dose ratio (FSDR) and fluorescence-normalized scan time (FNST) were used as metrics to assess results. Results: Calculated XRF/scatter spectra for 1-mm Pb and 0.9-mm Sn filters matched (r ≥ 0.996) experimental measurements. Calculated spectra representing additional filtration for both filter materials showed that the spectral hardening improved the FSDR at the expense of requiring a much longer FNST. In general, using Sn instead of Pb, at a given filter thickness, allowed an increase of up to 20% in FSDR, more prominent gold XRF peaks, and up to an order of magnitude decrease in FNST. Simulations using quasimonochromatic spectra suggested that increasing source x-ray energy, in the

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

    Sun, Yue, E-mail: ysun@u.northwestern.edu [Graduate Program in Applied Physics, Northwestern University, Evanston, IL 60208 (United States); Gleber, Sophie-Charlotte, E-mail: gleber@aps.anl.gov [Argonne National Laboratory, Argonne, IL 60439 (United States); Jacobsen, Chris, E-mail: cjacobsen@anl.gov [Argonne National Laboratory, Argonne, IL 60439 (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); Kirz, Janos, E-mail: jkirz@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Vogt, Stefan, E-mail: vogt@aps.anl.gov [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2015-05-15

    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. - Highlights: • We present a model for x-ray fluorescence detection with scanned x-ray beams. • We use it to compare detector

  20. X-Ray Fluorescence Spectrometry. II. Determination of Uranium in ores

    A method of analysis of uranium in ores by X-ray spectrometry was developed, using the internal standard technique. Strontium was found to be the most suitable internal standard for general use. A Norelco Philips X-ray fluorescent spectrometer was used in this work, equipped with a lithium fluoride crystal acting as a diffraction grating analyzer. The intensity of the uranium-L α1 spectral line is calculated and related to corresponding strontium-Kα spectral line, both detected with a Scintillation Counter. (Author) 31 refs

  1. Chlorophyll Fluorescence Spectra as an Indicator of X-Ray + EMS-Induced Phytotoxicity in Safflower

    Pandey, Jitendra Kumar; Srivastava, Preeti; Yadav, Ram Singh; Gopal, Ram

    2012-01-01

    The present investigation deals with the study of in vivo laser-induced chlorophyll florescence spectra (LICF) of safflower leaves (Carthamus tinctorius L.) for X-rays + EMS-treated plants. Seeds were treated with different doses of X-ray + EMS (5, 8, 12, 25, and 30 Kr + 0.5% EMS) and were grown in the green house. The effects of the concerned treatment on chlorophyll (Chl) contents and Chl fluorescence were investigated after 7 days of germination. Results obtained revealed that the values o...

  2. Analysis of siliceous geologic materials by energy-dispersive X-ray fluorescence

    The determination of the elements Al, Si, K, Ca, Ti, Cr, Mn and Fe in siliceous geologic samples by energy-dispersive X-ray fluorescence is investigated using the most adequate excitation conditions: direct excitation mode (rhodium anode X-ray tube) for the former two elements, and the secondary targets titanium for K and Ca, and germanium for Ti, Cr, Mn and Fe. For the correction of matrix effects the use of ratio methods has been tested. Procedure files have been defined allowing the automatic simultaneous acquisition and processing of spectra. (author)

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

    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. - Highlights: • We present a model for x-ray fluorescence detection with scanned x-ray beams. • We use it to compare detector

  4. Determination of Co in MgO matrix by wavelength dispersive X-ray fluorescence technique

    A Wavelength Dispersive X-ray Fluorescence (WDXRF) method for the analysis of Co in Mg matrix has been developed. The minimum determination limit achieved is 1 ppm. Special care has been taken in making the double layer pellet of synthetic standards such that the pellet after several exposures to x-rays does not become brittle. The working range for this method is 1-100 ppm. The relative percentage standard deviation calculated for the above range varies from 21% to 0.5%. (author)

  5. Molar concentration from sequential 2-D water-window X-ray ptychography and X-ray fluorescence in hydrated cells

    Jones, M. W. M.; Elgass, K. D.; Junker, M. D.; de Jonge, M. D.; van Riessen, G. A.

    2016-04-01

    Recent developments in biological X-ray microscopy have allowed structural information and elemental distribution to be simultaneously obtained by combining X-ray ptychography and X-ray fluorescence microscopy. Experimentally, these methods can be performed simultaneously; however, the optimal conditions for each measurement may not be compatible. Here, we combine two distinct measurements of ultrastructure and elemental distribution, with each measurement performed under optimised conditions. By combining optimised ptychography and fluorescence information we are able to determine molar concentrations from two-dimensional images, allowing an investigation into the interactions between the environment sensing filopodia in fibroblasts and extracellular calcium. Furthermore, the biological ptychography results we present illustrate a point of maturity where the technique can be applied to solve significant problems in structural biology.

  6. Gold estimation in geological samples using energy dispersive X-ray fluorescence spectroscopy

    Gold concentration in Indus river sediments have been estimated using energy dispersive X-ray fluorescence (EDXRF) spectrometry. To get the best possible detection sensitivity, optimisation of sample preparation procedure and exciting radiation was done. Physical preconcentration procedure of panning of heavy minerals has been employed. Samples were dissolved in acqua regia to homogenize the distribution of gold. For obtaining an optimum excitation sensitivity, radioisotope sources of various energies as well as a low power laboratory built transmission type Mo X-ray tube have been used. L shell X-rays of gold have been used for qualitative analysis. For quantitative estimation, a combination of single element fundamental parameter method and scattered radiation standardisation method was used. The sensitivity of EXDRF spectrometer for gold was around 50 ppm. (author). 6 figs., 2 tables

  7. Dosage of silicon in a soluble silicate using an x-ray-fluorescence radioisotopic method

    A description is given of a spectrometer for X ray fluorescence analysis having a radio active excitation source. It has been applied to the analysis of the silicon contained in an industrial soluble silicate. A theoretical study has been made for this analysis of the operational conditions such as: the effect of the particle size, the dilution of the sample, the sensitivity as a function of the X ray excitation energy. It is possible to obtain a relative accuracy of 0,87 per cent for the silicon determination, for one standard deviation. A comparison is made of the sensitivity obtained using this apparatus for the Si determination with that which can be obtained using a conventional apparatus fitted with an X ray tube. (author)

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

    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%.

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

    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

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

    Necemer, Marijan [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)], E-mail: marijan.necemer@ijs.si; Kump, Peter; Scancar, Janez; Jacimovic, Radojko; Simcic, Jurij; Pelicon, Primoz; Budnar, Milos; Jeran, Zvonka [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Pongrac, Paula; Regvar, Marjana; Vogel-Mikus, Katarina [Department of Biology, Biotechnical Faculty, University of Ljubljana, Vecna pot 111, SI-1000 Ljubljana (Slovenia)

    2008-11-15

    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, sensitive and

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

    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, sensitive and

  12. Application of X ray fluorescence techniques for the determination of hazardous and essential trace elements in environmental and biological materials

    Full text: The utilization of X ray fluorescence (XRF) technique for the determination of trace element concentrations in environmental and biological samples is presented. The analytical methods used include energy dispersive X ray fluorescence (EDXRF), total reflection X ray fluorescence (TXRF), micro-beam X ray fluorescence and direct in situ X-ray fluorescence analysis. The measurements have been performed with X ray tube- and radioisotope-based energy dispersive X ray fluorescence spectrometers. Both liquid nitrogen- and thermo electrically-cooled silicon detectors were utilized in the analysis. Samples analysed include soil, water, plant material, and airborne particulate matter collected on filters. Depending on the technique and the investigated elements, the above-mentioned samples were analysed either directly or indirectly (after decomposing the sample in a mineralization process or/and chemical preconcentration procedure). The achieved detection limits for different techniques, established by measuring appropriate reference standards, are presented. The utilization of the micro-beam XRF technique for studying element distribution in heterogeneous samples and investigating the 3D- and 2D-morphology of minute samples by means of computerized X ray absorption and X ray fluorescence tomography is described. The different X ray techniques have their unique advantages. The micro-beam X ray fluorescence set-up has an advantage of producing very well collimated primary X ray beam (by means of X ray capillary optics the beam is collimated down to about 15 μm in diameter), in front of which the analysed sample can be precisely positioned, providing local information about the sample composition. TXRF technique has its leading edge in analysis of liquid samples, and as a reference method for a conventional bulk EDXRF analysis of heterogeneous materials such as air particulates collected on filter where the particle size effects can seriously influence the

  13. Evaluation of different synchrotron beamline configurations for X-ray fluorescence analysis of environmental samples.

    Barberie, Sean R; Iceman, Christopher R; Cahill, Catherine F; Cahill, Thomas M

    2014-08-19

    Synchrotron radiation X-ray fluorescence (SR-XRF) is a powerful elemental analysis tool, yet synchrotrons are large, multiuser facilities that are generally not amenable to modification. However, the X-ray beamlines from synchrotrons can be modified by simply including X-ray filters or removing monochromators to improve the SR-XRF analysis. In this study, we evaluated four easily applied beamline configurations for the analysis of three representative environmental samples, namely a thin aerosol sample, an intermediate thickness biological sample, and a thick rare earth mineral specimen. The results showed that the "white beam" configuration, which was simply the full, polychromatic output of the synchrotron, was the optimal configuration for the analysis of thin samples with little mass. The "filtered white beam" configuration removed the lower energy X-rays from the excitation beam so it gave better sensitivity for elements emitting more energetic X-rays. The "filtered white beam-filtered detector" configuration sacrifices the lower energy part of the spectrum (<15 keV) for improved sensitivity in the higher end (∼26 to 48 keV range). The use of a monochromatic beam, which tends to be the standard mode of operation for most SR-XRF analyses reported in the literature, gave the least sensitive analysis. PMID:25025342

  14. X-ray fluorescence applied to the fission time study of Z=120 element

    Characteristic X-rays of the element Z=120 have been identified in the reaction 238U+64Ni at 6,6 MeV per nucleon. They have been detected in coincidence with fission fragments arising from composite systems with 120 protons formed during the reaction. Pieces of information about the formation probability by fusion of Z=120 nuclei and on the fission time of this nucleus have been inferred from the X-ray multiplicity. From the maximal measured X-ray multiplicity and with the assumption of an exponential distribution of fission times, we have determined an inferior limit of 4.0*10-18 s for the mean fission time of Z=120 nuclei. This maximal measured X-ray has also allowed us to state that at best 38% of capture reactions (it means quasi-fission + fusion reactions) correspond to quasi-fission reactions associated with times below than 10-19 seconds. This relatively low percentage of quasi-fission reactions is not consistent with the very low fusion probabilities generally expected for our system. This work has shown that the X-ray fluorescence technique can be used successfully for studying the stability of super-heavy elements

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

    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.

  16. Utilization of fluorescent uranium x-rays as verification tool for irradiated CANDU fuel bundles

    The use of fluorescent uranium x-rays for in-situ safeguards verification of irradiated CANDU fuel bundles is described. Room temperature CdZnTe (supergrade) semiconductor detector of low sensitivity coupled to charge sensitive pre-amplifier is used. This detector is characterized by moderate resolving power in the low energy region around 100 keV. It as such allows the separation of uranium x-rays in the close proximity of tungsten x-rays emanating from the shielding/collimator assembly. On account of strong attenuation, the detection of low energy x-rays requires the shielding to be of an optimized thickness. Further, in view of high intensity of this radiation the use of small volume detector is warranted. In dealing with the subject, this paper therefore presents an assessment, not only of the detector but also the shield-collimator assembly for the required verification of short cooling time fuel bundles. Results of the associated optimization measurements with respect to collimator aperture and detector sensitivity are consequently included. The future course of work from the viewpoint of development of a suitable x-ray spectrometer specifically for the purpose of verifying extremely short (< 1 month old) cooling time fuel bundles is moreover identified. (author)

  17. An imaging X-ray fluorescence spectrometer for near earth objects

    We propose a novel imaging X-ray spectrometer to be flown on a space mission to a Near Earth Object (NEO) (the Moon, a near Earth asteroid or a comet). In either of the first two cases the instrument will record X-ray fluorescence excited from the surface by the solar X-ray flux to form 'compositional maps' of its surface, providing valuable information on the evolution of these objects. In the case of a comet, the device will study the X-ray emission resulting from its interaction with the solar wind. During cruise when the spacecraft is en-route to the NEO the instrument will be used to make astronomical observations of Active Galactic Nuclei (AGN), X-ray binary stars and coronal sources in star clusters such as the Pleiades or Hyades. The instrument, proposed for ESA's SMART-1 mission, is a miniature telescope, of 37.5 cm focal length, based on microchannel plate (MCP) optics and charged coupled device (CCD) detectors providing both imaging and a medium resolution ∼50-100 eV spectroscopic capability; sufficient to resolve the L lines of Ca, Ti, Fe, and the K lines of O, Mg, Al and Si with an angular resolution ∼10 arcmin and a 6x6 deg. field of view

  18. A flexible setup for angle-resolved X-ray fluorescence spectrometry with laboratory sources

    Spanier, M.; Herzog, C.; Grötzsch, D.; Kramer, F.; Mantouvalou, I.; Lubeck, J.; Weser, J.; Streeck, C.; Malzer, W.; Beckhoff, B.; Kanngießer, B.

    2016-03-01

    X-ray fluorescence (XRF) analysis is one of the standard tools for the analysis of stratified materials and is widely applied for the investigation of electronics and coatings. The composition and thickness of the layers can be determined quantitatively and non-destructively. Recent work showed that these capabilities can be extended towards retrieving stratigraphic information like concentration depth profiles using angle-resolved XRF (ARXRF). This paper introduces an experimental sample chamber which was developed as a multi-purpose tool enabling different measurement geometries suited for transmission measurements, conventional XRF, ARXRF, etc. The chamber was specifically designed for attaching all kinds of laboratory X-ray sources for the soft and hard X-ray ranges as well as various detection systems. In detail, a setup for ARXRF using an X-ray tube with a polycapillary X-ray lens as source is presented. For such a type of setup, both the spectral and lateral characterizations of the radiation field are crucial for quantitative ARXRF measurements. The characterization is validated with the help of a stratified validation sample.

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

    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.

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

    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

  1. Total reflection X-ray fluorescence and energy-dispersive X-ray fluorescence analysis of runoff water and vegetation from abandoned mining of Pb-Zn ores

    The present work reports on the heavy metal content: Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd and Pb in running waters and vegetation around abandoned mining areas. Two species of mosses (Dicranum sp. and Pleurocarpus sp.) and three different species of wild grass (Bromus sp., Rumex sp. and Pseudoavena sp.) growing on the surrounding areas of old lead-zinc mines (Aran Valley, Pyrenees, NE Spain) have been analyzed. Both water and vegetation were collected in two different sampling places: (a) near the mine gallery water outlets and (b) on the landfill close to the abandoned mineral concentration factories. For the heavy metal content determination, two different techniques were used: total reflection X-ray fluorescence for water analysis and energy-dispersive X-ray fluorescence for vegetation study. Surface waters around mine outlets exhibit anomalous content of Co, Ni, Zn, Cd. Stream waters running on mining landfills exhibit higher Cu, Zn, Cd and Pb than those of the waters at the mine gallery outlets. The results allow us to assess the extent of the environmental impact of the mining activities on the water quality. The intake of these elements by vegetation was related with the sampling place, reflecting the metal water content and the substrate chemistry. Accumulation of metals in mosses is higher than those exhibited in wild grasses. Furthermore, different levels of accumulation were found in different wild grass. Rumex sp. presented the lowest metal concentrations, while Pseudoavena sp. reported the highest metal content

  2. Total reflection X-ray fluorescence and energy-dispersive X-ray fluorescence analysis of runoff water and vegetation from abandoned mining of Pb Zn ores

    Marques, A. F.; Queralt, I.; Carvalho, M. L.; Bordalo, M.

    2003-12-01

    The present work reports on the heavy metal content: Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd and Pb in running waters and vegetation around abandoned mining areas. Two species of mosses ( Dicranum sp. and Pleurocarpus sp.) and three different species of wild grass ( Bromus sp., Rumex sp. and Pseudoavena sp.) growing on the surrounding areas of old lead-zinc mines (Aran Valley, Pyrenees, NE Spain) have been analyzed. Both water and vegetation were collected in two different sampling places: (a) near the mine gallery water outlets and (b) on the landfill close to the abandoned mineral concentration factories. For the heavy metal content determination, two different techniques were used: total reflection X-ray fluorescence for water analysis and energy-dispersive X-ray fluorescence for vegetation study. Surface waters around mine outlets exhibit anomalous content of Co, Ni, Zn, Cd. Stream waters running on mining landfills exhibit higher Cu, Zn, Cd and Pb than those of the waters at the mine gallery outlets. The results allow us to assess the extent of the environmental impact of the mining activities on the water quality. The intake of these elements by vegetation was related with the sampling place, reflecting the metal water content and the substrate chemistry. Accumulation of metals in mosses is higher than those exhibited in wild grasses. Furthermore, different levels of accumulation were found in different wild grass. Rumex sp. presented the lowest metal concentrations, while Pseudoavena sp. reported the highest metal content.

  3. Characterization of energy response for photon-counting detectors using x-ray fluorescence

    Purpose: To investigate the feasibility of characterizing a Si strip photon-counting detector using x-ray fluorescence. Methods: X-ray fluorescence was generated by using a pencil beam from a tungsten anode x-ray tube with 2 mm Al filtration. Spectra were acquired at 90° from the primary beam direction with an energy-resolved photon-counting detector based on an edge illuminated Si strip detector. The distances from the source to target and the target to detector were approximately 19 and 11 cm, respectively. Four different materials, containing silver (Ag), iodine (I), barium (Ba), and gadolinium (Gd), were placed in small plastic containers with a diameter of approximately 0.7 cm for x-ray fluorescence measurements. Linear regression analysis was performed to derive the gain and offset values for the correlation between the measured fluorescence peak center and the known fluorescence energies. The energy resolutions and charge-sharing fractions were also obtained from analytical fittings of the recorded fluorescence spectra. An analytical model, which employed four parameters that can be determined from the fluorescence calibration, was used to estimate the detector response function. Results: Strong fluorescence signals of all four target materials were recorded with the investigated geometry for the Si strip detector. The average gain and offset of all pixels for detector energy calibration were determined to be 6.95 mV/keV and −66.33 mV, respectively. The detector’s energy resolution remained at approximately 2.7 keV for low energies, and increased slightly at 45 keV. The average charge-sharing fraction was estimated to be 36% within the investigated energy range of 20–45 keV. The simulated detector output based on the proposed response function agreed well with the experimental measurement. Conclusions: The performance of a spectral imaging system using energy-resolved photon-counting detectors is very dependent on the energy calibration of the

  4. Study of uranium contamination of ground water in Punjab using X-ray fluorescence technique

    A number of reports have appeared in public media about uranium ingestion being a possible cause for cancer and increased birth rate abnormalities among children in the Malwa region of Punjab state in India. These reports link problems like cancer and Autism, with the presence of uranium in the ground waters of Malwa region. The concentration of uranium in drinking water from sources as varied as ground water, canal water supply and reverse osmosis system have been investigated using X-ray fluorescence technique. Samples from the thermal power plants in the regions and nearby ground waters were also analyzed to identify the source of contamination. The samples were collected with assistance of the officials from the Government of Punjab. More than half a litre of each of the water samples was dried at 60 deg-80 deg in an oven. Residue was collected using larger quantities of water samples in case of RO water samples. The elemental analysis of the residue was carried out using the Energy-Dispersive X-Ray Fluorescence (EDXRF) spectrometer consisting of an 42Mo-anode X-ray tube (Panalytical, 2.5 kW) as an excitation source and a Si(Li) detector. A combination of selective absorbers of 30Zn, 38Sr, and 39Y was used in the incident beam for improving the detection limit for Uranium by reducing the background and removing the 42Mo K X-rays. The detection limit in ppb/litre depends upon the amount of residue

  5. Analyses of archaeological pottery samples using X-ray fluorescence technique for provenance study

    Archaeological artifacts reveal information on past human activities, artifact preparation technology, art and possible trade. Ceramics are the most stable and abundant material in archaeological context. Pottery is the most abundant tracers in all archaeological excavations. Compared to major elements, elements present at trace concentrations levels are source specific and they maintain same concentration levels in source clay as well as finished products e.g., fired clay potteries. As it is difficult to find out exact source or origin, provenance study is carried out first to establish whether objects under study are from the same or different sources/origin. Various analytical techniques like instrumental neutron activation analysis (INAA), Ion beam analysis (IBA) and X-ray fluorescence (XRF) have been used for obtaining elemental concentrations in archaeological potteries. Portable X-ray fluorescence (pXRF) spectrometry provides a non-destructive means for elemental characterization of a wide range of archaeological materials. Ten archaeological pottery samples were collected from Kottapuram, Kerala under the supervision of archaeological survey of India. Portable X-ray fluorescence (pXRF) spectrometry using a handheld Olympus Innov-X Delta XRF device, ACD BARC, has been used for chemical characterization of the pottery samples. The instrument is equipped with the Delta Rhodium (Rh) anode X-Ray tube and uses a Silicon Drift Detector (resolution <200 eV at 5.95 keV Mn Kα X-ray). NIST 2781 SRM was analyzed for quality control purpose. Ten elements namely Fe, Ti, Mn, Co, Cu, Zn, Pb, Zr, Mo and Se were chosen for cluster analysis and their concentration values were utilized for multivariate statistical analysis using WinSTAT 9.0

  6. Oscillating dipole model for the X-ray standing wave enhanced fluorescence in periodic multilayers

    André, Jean-Michel; Jonnard, Philippe

    2013-01-01

    Periodic multilayers give rise to enhanced X-ray fluorescence when a regime of standing waves occurs within the structure. This regime may concern the primary radiation used to induce the fluorescence, the secondary radiation of fluorescence or both of them. Until now, existing models only dealt with standing wave regime of primary radiation. We present a theoretical approach based on the oscillating dipole model and the coupled-wave theory that can treat efficiently any standing wave regime. We compare our simulations to experimental data available in the literature.

  7. Correction method for self-absorption effects of fluorescence x-ray absorption near-edge structure on multilayer samples

    It is well known that fluorescence x-ray absorption spectroscopy suffers from the self-absorption effects for thick and concentrated samples. In this study, a simple correction method is provided for correcting the self-absorption effects of fluorescence x-ray absorption near edge structure (XANES) spectrum for multilayer samples. This method is validated by application on fluorescence XANES spectra for a Cr/C multilayer measured at different incidence angles. The errors produced by the self-absorption effects for the measured fluorescence x-ray absorption spectra without corrections are also estimated and discussed. (paper)

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

    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.

  9. Monitoring the mass of UF6 gas and uranium deposits in aluminium pipes using X-ray fluorescence and X-ray transmission gauges

    In order to determine the enrichment of UF6 gas in centrifuge plant pipework it is necessary to measure the mass of the gas (pressure) and the mass per unit area of any uranium deposited on the pipe. This paper shows that it is possible to determine the pressure of the UF6 gas in pipes 120 mm in diameter using an energy-dispersive X-ray fluorescence spectrometer. Results are also given of transmission measurements made using a low power X-ray generator operated at two different applied voltages. A method of using the two measurements to determine the mass per unit area of deposited uranium is described. (author)

  10. 3D Micro-PIXE at atmospheric pressure: A new tool for the investigation of art and archaeological objects

    The paper describes a novel experiment characterized by the development of a confocal geometry in an external Micro-PIXE set-up. The position of X-ray optics in front of the X-ray detector and its proper alignment with respect to the proton micro-beam focus provided the possibility of carrying out 3D Micro-PIXE analysis. As a first application, depth intensity profiles of the major elements that compose the patina layer of a quaternary bronze alloy were measured. A simulation approach of the 3D Micro-PIXE data deduced elemental concentration profiles in rather good agreement with corresponding results obtained by electron probe micro-analysis from a cross-sectioned patina sample. With its non-destructive and depth-resolving properties, as well as its feasibility in atmospheric pressure, 3D Micro-PIXE seems especially suited for investigations in the field of cultural heritage