As of September 19, 2014

for international journal X-Ray Spectrometry (John Wiley & Sons Ltd.)

Micro analysis of heterogeneous aerosol particles (September 14, 2014)

So far, high-resolution microscopic analysis of individual atmospheric particles has been fairly difficult because of problems with the filters used for capturing particles.  The research group in the National Institute for Standards and Technologies, United States, is proposing a multiplatform approach for microscopically assessing chemical and optical properties of individual heterogeneous urban dust particles.  The procedures described in the paper could also be useful for similar analysis.  The method uses 5 steps; (i) particles embedded in fibrous filters are transferred to polished silicon/germanium wafers with electrostatically-assisted high-speed centrifugation, (ii) particles with light absorbing/scattering behavior are identified from bright/dark field light-microscopy, (iii) particles identified from light microscopy are compositionally mapped at high-definition with field-emission scanning electron microscopy and energy-dispersive X-ray spectroscopy, (iv) compositionally-mapped particles are further analyzed with focused ion-beam (FIB) tomography whereby a series of thin slices from a particle are imaged, and the resulting image stack is used to construct a 3-dimensional model of the particle, and (v) particle chemistry is assessed over two distinct regions of a thin FIB slice of a particle with energy-filtered transmission electron microscopy (TEM) and electron energy-loss spectroscopy associated with scanning TEM.  For more information, see the paper, "Qualitative Multiplatform Microanalysis of Individual Heterogeneous Atmospheric Particles From High-Volume Air Samples", J. M. Conny et al., Anal. Chem., Just Accepted (DOI: 10.1021/ac5022612 Publication Date (Web): September 14).

Full-field XANES imaging (August 11, 2014)

Professor L. Vincze (Ghent University, Belgium) and his colleagues have reported on the latest fluorescence mode XANES imaging using the SLcam, which is an energy dispersive pnCCD detector.  At BM26A, ESRF, the measurements were done for iron foil with some oxides and geological standard samples.  The typical detection limit and measuring time were 0.5 wt% and 15 h, respectively.  Readers might think that energy-resolution can be sacrificed near the absorption edges of interest in order to shorten the measuring time in the same way as ordinary XANES measurement by means of X-ray fluorescence.  Although the use of ordinary X-ray CCD in accumulation mode for a very similar experiment was published 10 years ago (for example, M. Mizusawa et al, J. Synchrotron Rad. 11, 209 (2004)), the present system has the advantage of being able to reduce the background from the major light elements contained in the sample.  For more information, see the paper, "Full-Field Fluorescence Mode Micro-XANES Imaging Using a Unique Energy Dispersive CCD Detector", P. Tack et al, Anal. Chem., 86, 8791(2014).

Synchrotron micro X-ray fluorescence analysis of radioactive air-particulates emitted by the nuclear power plant accident in Fukushima, Japan (August 1, 2014)

A research team led by Professor I. Nakai (Tokyo University of Science, Japan) has recently clarified the detailed chemical nature of radioactive aerosol microparticles emitted during the Fukushima Daiichi Nuclear Power Plant accident.  They collected three fine particles of 2 microns in dia, containing radioactive cesium, on March 14th and 15th, 2011, in Tsukuba, 172 km away from the power plant.  In addition to Fe, Zn, Rb, Zr, Mo, Sn, Sb, Te, Cs, and Ba, U was detected in two particles.  The oxidation states of the heavy elements were also studied by X-ray absorption spectra.  The experiments were done at BL37XU, SPring-8, Japan.  For more information, see the paper, "Detection of Uranium and Chemical State Analysis of Individual Radioactive Microparticles Emitted from the Fukushima Nuclear Accident Using Multiple Synchrotron Radiation X-ray Analyses", Y. Abe et al., Anal. Chem., 86, 8521 (2014).
 

Gunshot residue analysis by X-ray fluorescence (August 1, 2014)

Professor J. Wang (University of California San Diego, USA) and his colleagues have applied X-ray fluorescence to the analysis of gunshot residue, which has been usually detected based on the analysis trace amounts of metallic and organic species deposited on the hands, face, hair, and clothing of the shooter.  The researchers tried to couple square-wave stripping voltammetry (SWSV) and scanning electron microscopy (SEM) plus energy dispersive X-ray spectroscopy (EDX).  The former method can be used as a rapid screening tool, while the latter contributes to confirmation of the presence of the characteristic morphology and metal composition of gunshot residue particles.  For more information, see the paper, "Orthogonal Identification of Gunshot Residue with Complementary Detection Principles of Voltammetry, Scanning Electron Microscopy, and Energy-Dispersive X-ray Spectroscopy: Sample, Screen, and Confirm", A. M. O’Mahony et al., Anal. Chem., 86, 8031 (2014).
 

Precise time measurement in sub-femtosecond by the use of X-ray free-electron laser (July 27, 2014)

It is now known that X-ray free-electron lasers can produce ultrafast X-ray pulses as short as 3 fs in FWHM.  Scientists at the Linac Coherent Light Source (LCLS), Stanford are trying to reduce delay time errors in optical-pump & X-ray probe measurements to the 1 fs level, by 2D spectrogram measurement of the relative X-ray/optical delay.  For more information, see the paper, "Sub-femtosecond precision measurement of relative X-ray arrival time for free-electron lasers", N. Hartmann et al., Nature Photonics, 8, 706 (2014).
 

Comparison of excitation mode in synchrotron X-ray fluorescence of environmental samples (July 15, 2014)

Professor T. M. Cahill (Arizona State University) and his colleagues have recently compared the performance of the different excitation modes of synchrotron radiation X-ray fluorescence.  The research team evaluated four different beamline configurations for the analysis of three representative environmental samples; a thin aerosol sample, an intermediate thickness biological sample, and a thick rare earth mineral specimen.  They found that white beam excitation is optimal for the analysis of thin samples with little mass, and that filtered white beam excitation (removing lower energy X-rays by absorber) gives better sensitivity for elements emitting more energetic X-rays.  In their study, monochromatic excitation, which tends to be the standard mode of operation, did not give good results in terms of sensitivity.  For more information, see the paper, "Evaluation of Different Synchrotron Beamline Configurations for X.ray Fluorescence Analysis of Environmental Samples", S. R. Barberie et al., Anal. Chem., 86, 8253 (2014).
 

Application of TXRF to the monitoring of bioaccumulation in gold nano-rods (July 7, 2014)

A Spanish group has recently published a very interesting application of total-reflection X-ray fluorescence (TXRF).  The research team has evaluated the bioaccumulation kinetics of gold nanorods (GNRs) in various tissues upon intravenous administration in mice.  It was found that the main achievement was clearly differentiating two kinds of behaviors; gold nano rods were quickly bioaccumulated by highly vascular filtration organs such as the liver and spleen, while they do not show bioaccumulation rates in the brain and lung for the period of time investigated.  For more information, see the paper, "Evaluation of Bioaccumulation Kinetics of Gold Nanorods in Vital Mammalian Organs by Means of Total Reflection X-Ray Fluorescence Spectrometry", R. Fernandez-Ruiz et al., Anal. Chem., 86, 7383 (2014).
 

Use of Compton-to-Rayleigh scattering intensity ratio for the aid of reference-free X-ray analysis (June 20, 2014)

Dr. V-D. Hodoroaba (BAM, Berlin, Germany) and his colleague have published a report on the feasibility of quantitative X-ray fluorescence (XRF) analysis using coherent (Rayleigh) and incoherent (Compton) X-ray scattering.  They have evaluated the ratio of the Compton-to-Rayleigh intensity observed in XRF spectra and also have discussed its relation to the average atomic number.  In so-called reference-free XRF analysis, which uses only fundamental parameters and a theoretical formula and does not rely on the calibration curve, there still exist many difficulties, particularly for matrices of lower mean atomic numbers.  The analysis presented in this research has sufficiently high sensitivity to distinguish the average atomic number of specimens even within the 0.1 difference.  For more information, see the paper, "Gaining Improved Chemical Composition by Exploitation of Compton-to-Rayleigh Intensity Ratio in XRF Analysis", V-D. Hodoroaba et al., Anal. Chem., 86, 6858 (2014).
 

Spin-charge dynamics of iron complex clarified by ultrafast X-ray spectroscopy (May 15, 2014)

The use of X-ray free-electrons has enabled plenty of fascinating science, such as watching non-equilibrium excited-state dynamics in complexes of 3d transition metals.  Scientists at LCLS, Stanford have performed femtosecond resolution X-ray fluorescence spectroscopy, with its sensitivity to spin state, elucidating the spin crossover dynamics of [Fe(2, 2ˈ-bipyridine)₃]²⁺ on photoinduced metal-to-ligand charge transfer excitation.  For more information, see the paper, "Tracking excited-state charge and spin dynamics in iron coordination complexes", W. Zhang et al., Nature, 509, 345 (2014).
 

X-ray analysis on Mars is hot (August 9, 2014)

Most X-ray experiments can be done at high quality with ease in an ordinary laboratory.  Some experiments, however, have to be done in the field.  It is hard to imagine a more extreme definition of “in the field” than the planet of Mars, which is why exciting times have come about since NASA's Mars rover “Curiosity" landed on Mars in August 2012.  It has since recorded and sent back a large number of datasets including X-ray fluorescence (XRF) and X-ray diffraction (XRD) data.  Naturally, the scientists involved with the projects have been speaking globally since.  During EXRS 2014 (June, Bologna, Italy), Professor J. L. Campbell (University of Guelph, Canada) gave a keynote lecture entitled "XRF and PIXE on the Mars Science LAB Curiosity Rover".  At the Denver X-ray conference (July, Big Sky, Montana), the Plenary Session was "X-rays on Mars", and 3 scientists gave lectures. Professor D. L. Bish (Indiana University) gave a talk entitled "The First X-ray Diffraction Results From Mars".  Professor J. L. Campbell's talk on “XRF Combines with PIXE in Curiosity's Alpha Particle X-ray Spectrometer” was the extension on his talk at EXRS 2014, and further detailed and specific discussion was done there. Professor S.M. Clegg talked about "Exploring Mars with ChemCam on the Curiosity Rover" (ChemCam enables quick element determination by the laser-induced plasma emission spectroscopy).  In August, at Montreal, during the International Union of Crystallography's congress, Professor D. L. Bish gave a talk entitled "The First X-ray Powder Diffraction Measurements on Mars".  These talks highlighted many interesting technological aspects of the measurements: XRF analysis is done first by the same CCD camera, which works as an energy-dispersive 2D X-ray detector, even when the main aim of the measurement is obtaining the XRD pattern.  In the analysis of unknown samples, generally both chemical composition and the crystal structure are indispensable.  Another reason is that XRF helps the systematic use of single photon counting mode of the CCD camera to get a good quality XRD pattern.  Secondly, the samples are vibrated all the time to ensure a smooth and continuous Debye ring.  The rover furthermore contains a series of standard samples to check the reliability and reproducibility of the measurements.  The readers might be interested in such a compact X-ray analyzer, which combined both XRD and XRF machine.  Very similar system is now commercially available.  For further information on the scientific activity on Mars, visit the Web page, http://mars.jpl.nasa.gov/msl/
 

Denver X-ray conference awards (July 30, 2014)

During the plenary session of the 65^th Annual Denver X-Ray Conference, two awards were presented.  The 2014 Birks Award was presented to George Havrilla, Los Alamos National Laboratory for his many contributions to microXRF, especially the development of the confocal XRF microscope. Dr. Havrilla has been a leader in the field of analytical XRF; including 19 years on the Denver X-ray Conference Organizing Committee; nine years as North American Editor of X-ray Spectrometry; and six years as Co-Editor-in-Chief for Advances in X-ray Analysis.  The ICDD Fellow Award was presented to John Getty, Instructor in Geophysical Engineering and Principal Investigator in the Proppant Research Group at Montana Tech. John has played a key role in the planning and execution of the Denver X-ray Conference for more than 30 years.  For further information, visit the Web page, http://www.dxcicdd.com/
 

YouTube videos of Ultrafast X-ray Summer Seminar 2014 (June 19, 2014)

The Ultrafast X-ray Summer Seminar (UXSS) 2014 took place from June 15 to 19 at SLAC National Accelerator Laboratory, California, United States.  The program is organized specifically to train students and post-docs on new opportunities in ultrafast science, particularly using X-ray Free Electron Lasers.  Almost all the lectures presented by expert scientists are now available as videos on YouTube.  The lecture by Dr. Pieter Glatzel (ESRF) on "Hard X-ray Spectroscopy" (https://www.youtube.com/watch?v=0sMD8lZzuTE) is surely useful for young X-ray spectroscopists.  Other exciting lectures are available from Dr. Oleg Shpyrko (UCSD) on "Coherent X-ray Scattering at Ultrafast Timescales" (https://www.youtube.com/watch?v=OIR_ltSOl2U), Dr. Michael Odelius (Stockholm University) on "Electronic Structure & Ultrafast Solution Dynamics in Xray vision w/ theoretical spectacles" (https://www.youtube.com/watch?v=ITIzAmYuyWA), Dr. Alexander Fohlisch (Helmholtz Zentrum Berlin) on "Soft X-ray General and Solid State Aspects" (https://www.youtube.com/watch?v=xTz1oCV5cWI), Dr. Philippe Wernet (Helmholtz Zentrum Berlin) on "Ultrafast Molecular Spectroscopy with X-rays: Experiment", and Prof. Claudio Pellegrini (UCLA) on "X-ray Free Electron Lasers" (https://www.youtube.com/watch?v=5v68nuOTwns).  For more information on this summer seminar, visit the following Web site, https://conf-slac.stanford.edu/uxss-2014/

Rigaku’s new SmartLab 3 (June 16, 2014)

Bruker Corporation has announced that it has acquired Vutara Incorporated, a technology leader in high-speed, three-dimensional (3D), super-resolution fluorescence microscopy for life science applications.  Vutara’s estimated revenue for full year 2014 is expected to be approximately $2 million.  For further information, visit the web page, http://www.bruker.com/
 

Bruker acquires high-speed, 3D super-resolution fluorescence microscopy company Vutara (July 28, 2014)

Bruker Corporation has announced that it has acquired Prairie Technologies, Inc. (Prairie), a provider of life science fluorescence microscopy products.  For further information, visit the web page, http://www.bruker.com/

Spectris absorbs Claisse (July 18, 2014)

Spectris (LSE: SXS) has announced that it has acquired the business and assets of the Canadian company La Corporation Scientifique Claisse Inc., a business leader in sample preparation for atomic spectroscopy (including X-ray) analysis.  Revenues for the year ending March 2014 were CAD13 million.  Claisse will become part of the Materials Analysis segment of Spectris and will be integrated into PANalytical.  For further information, visit the web page, http://www.panalytical.com/
 

SpectroscopyNow.com

For additional news about X-ray analysis and other spectroscopy sciences, browse the Wiley website.

Kenji Sakurai
Director, X-Ray Physics Group, National Institute for
Materials Science (NIMS)
and Professor, Doctoral Program in Materials Science and
Engineering, Graduate School of Pure and Applied Sciences,
 University of Tsukuba
1-2-1, Sengen, Tsukuba, Ibaraki 305-0047 Japan
Phone : +81-29-859-2821, Fax : +81-29-859-2801
sakurai@yuhgiri.nims.go.jp
http://www.nims.go.jp/xray/lab/