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X-ray Microscope (x-ray + microscope)
Kinds of X-ray Microscope Selected AbstractsHard X-ray micro(spectro)scopy: A powerful tool for the geomicrobiologistsGEOBIOLOGY, Issue 3 2008K. M. KEMNER ABSTRACT During the past few decades, the use of electron microscopy approaches , many developed by Terry Beveridge , to probe the physiology of microorganisms has become a mainstay in fields including microbiology, human health, and geomicrobiology. Recent developments of third-generation synchrotron X-ray sources and X-ray-based microscopy approaches for studying microbial systems have proved their utility as complements to the very powerful approaches regularly employed by electron microscopists. In addition, in recent geomicrobiological studies, researchers have begun to take advantage of the strengths of each technique by using the superior spatial resolution of the electron microscope (relative to the X-ray microscope) and the superior elemental sensitivity of the X-ray microscope (relative to the electron microscope), along with the ability of the X-ray microscope to spatially probe the chemical speciation of elements. The benefits of integrating these two nanoprobes for investigating the same microenvironments within a geomicrobial system are far superior to those of independent studies separately employing each probe. [source] A study of the human hair structure with a Zernike phase contrast X-ray microscopeJOURNAL OF MICROSCOPY, Issue 2 2007HWA SHIK YOUN Summary We have observed the internal structure of human hair shafts with a transmission Zernike phase contrast hard X-ray microscope. Due to the high spatial resolution and the high contrast of the microscope, we could image scales, macrofibrils, medulla and melanin without staining. The structure of a black hair shaft is compared with that of a white one. [source] X-ray spectromicroscopy in soil and environmental sciencesJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2010J. Thieme X-ray microscopy is capable of imaging particles in the nanometer size range directly with sub-micrometer spatial resolution and can be combined with high spectral resolution for spectromicroscopy studies. Two types of microscopes are common in X-ray microscopy: the transmission X-ray microscope and the scanning transmission X-ray microscope; their set-ups are explained in this paper. While the former takes high-resolution images from an object with exposure times of seconds or faster, the latter is very well suited as an analytical instrument for spectromicroscopy. The morphology of clusters or particles from soil and sediment samples has been visualized using a transmission X-ray microscope. Images are shown from a cryo-tomography experiment based on X-ray microscopy images to obtain information about the three-dimensional structure of clusters of humic substances. The analysis of a stack of images taken with a scanning transmission X-ray microscope to combine morphology and chemistry within a soil sample is shown. X-ray fluorescence is a method ideally applicable to the study of elemental distributions and binding states of elements even on a trace level using X-ray energies above 1,keV. [source] Confocal full-field X-ray microscope for novel three-dimensional X-ray imagingJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2009Akihisa Takeuchi A confocal full-field X-ray microscope has been developed for use as a novel three-dimensional X-ray imaging method. The system consists of an X-ray illuminating `sheet-beam' whose beam shape is micrified only in one dimension, and an X-ray full-field microscope whose optical axis is normal to the illuminating sheet beam. An arbitral cross-sectional region of the object is irradiated by the sheet-beam, and secondary X-ray emission such as fluorescent X-rays from this region is imaged simultaneously using the full-field microscope. This system enables a virtual sliced image of a specimen to be obtained as a two-dimensional magnified image, and three-dimensional observation is available only by a linear translation of the object along the optical axis of the full-field microscope. A feasibility test has been carried out at beamline 37XU of SPring-8. Observation of the three-dimensional distribution of metallic inclusions in an artificial diamond was performed. [source] Three-dimensional chemical mapping by scanning transmission X-ray spectromicroscopyJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2007Göran A. Johansson Three-dimensional (3-d) chemical mapping using angle-scan tomography in a scanning transmission X-ray microscope is demonstrated. Apparatus, experimental procedures and data processing are presented and the 3-d spatial resolution is evaluated. The technique is illustrated using mapping of a low-density acrylate polyelectrolyte in and outside of polystyrene microspheres dispersed in water in a 4,µm-diameter microcapillary. The 3-d chemical visualization provides information about the microstructure that had not previously been observed. [source] Chemically selective soft X-ray patterning of polymersJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2007Jian Wang The chemically selective modification of polymer mixtures by monochromated soft X-rays has been explored using the high-brightness fine-focused 50,nm beam of a scanning transmission X-ray microscope. Four different polymer systems were examined: a polymethylmethacrylate (PMMA) polyacrylonitrile (PAN) bilayer film; a PMMA- blend -PAN microphase-separated film; a poly(MMA- co -AN) copolymer film; and a poly(ethyl cyanoacrylate) homopolymer film. A high level of chemically selective modification was achieved for the PMMA/PAN bilayer; in particular, irradiation at 288.45,eV selectively removed the carbonyl group from PMMA while irradiation at 286.80,eV selectively reduced the nitrile group of PAN, even when these irradiations were carried out at the same (x,y) position of the sample. In the last two homogenous polymer systems, similar amounts of damage to the nitrile and carbonyl groups occurred during irradiation at either 286.80 or 288.45,eV. This is attributed to damage transfer between the C[triple-bond]N and C=O groups mediated by primary electrons, secondary electrons or radical/ionic processes, aided by their close spatial proximity. Although the overall thickness of the bilayer sample at 70,nm is smaller than the lateral line spreading of 100,nm, the interface between the layers appears to effectively block the transport of energy, and hence damage, between the two layers. The origins of the line spreading in homogeneous phases and possible origins of the damage blocking effect of the interface are discussed. To demonstrate chemically selective patterning, high-resolution multi-wavelength patterns were created in the PMMA/PAN bilayer system. [source] A new bend-magnet beamline for scanning transmission X-ray microscopy at the Advanced Light SourceJOURNAL OF SYNCHROTRON RADIATION, Issue 4 2002Harald Ade The high brightness of the bend magnets at the Advanced Light Source has been exploited to illuminate a scanning transmission X-ray microscope (STXM). This is the first diffraction-limited scanning X-ray microscope to operate with a useful count rate on a synchrotron bend-magnet source. A simple dedicated beamline has been built covering the range of photon energy from 250,eV to 600,eV. The beamline is always available and needs little adjustment. Use of this facility is much easier than that of installations that share undulator beams. This facility provides radiation for C 1s, N 1s and O 1s near-edge X-ray absorption spectromicroscopy with STXM count rates in excess of 1,MHz and with spectral resolution typically 1:2000, limited to about 1:5000. [source] Zernike-type phase-contrast hard X-ray microscope with a zone plate at the Photon FactoryJOURNAL OF SYNCHROTRON RADIATION, Issue 3 2002Hiroki Yokosuka A Zernike-type phase-contrast X-ray microscope with a zone plate and a phase plate was constructed at the Photon Factory BL3C2. Parallel monochromatic X-rays of 8.97,keV were incident on a specimen and a direct beam transmitted through the specimen was focused on the back focal plane of the zone plate, where an aluminium phase plate was placed. Tantalum line patterns as fine as 0.3,µm could be imaged. Phase-contrast images of polypropylene wires and polystyrene latex beads were obtained, which showed better contrast than that of their bright field images. [source] Organic matter from comet 81P/Wild 2, IDPs, and carbonaceous meteorites; similarities and differencesMETEORITICS & PLANETARY SCIENCE, Issue 10 2009S. Wirick Sections were analyzed using a scanning transmission X-ray microscope (SXTM) and carbon X-ray absorption near edge structure (XANES) spectra were collected. We compared the carbon XANES spectra of these Wild 2 samples with a database of spectra on thirty-four interplanetary dust particles (IDPs) and with several meteorites. Two of the particles analyzed are iron sulfides and there is evidence that an aliphatic compound associated with these particles can survive high temperatures. An iron sulfide from an IDP demonstrates the same phenomenon. Another, mostly carbon free containing particle radiation damaged, something we have not observed in any IDPs we have analyzed or any indigenous organic matter from the carbonaceous meteorites, Tagish Lake, Orgueil, Bells and Murchison. The carbonaceous material associated with this particle showed no mass loss during the initial analysis but chemically changed over a period of two months. The carbon XANES spectra of the other four particles varied more than spectra from IDPs and indigenous organic matter from meteorites. Comparison of the carbon XANES spectra from these particles with 1. the carbon XANES spectra from thirty-four IDPs (<15 micron in size) and 2. the carbon XANES spectra from carbonaceous material from the Tagish Lake, Orgueil, Bells, and Murchison meteorites show that 81P/Wild 2 carbon XANES spectra are more similar to IDP carbon XANES spectra then to the carbon XANES spectra of meteorites. [source] X-ray imaging of various biological samples using a phase-contrast hard X-ray microscopeMICROSCOPY RESEARCH AND TECHNIQUE, Issue 9 2008Guk Bae Kim Abstract In this study, we visualized the internal structures of various bio-samples and found the optimum conditions of test samples for the 7 keV hard X-ray microscope of the Pohang light source. From the captured X-ray images, we could observe the intercellular and intracellular structures of dehydrated human cells and mouse tumor tissues without using any staining materials in a spatial resolution better than 100 nm. The metastasized lung tissue, which was several tens of micrometers in thickness, was found to be very well suited to this hard X-ray microscope system, because it is nearly impossible to observe such a nontransparent and thick sample with a high spatial resolution better than 100 nm using any microscopes such as a soft X-ray microscope, an optical microscope, or an electron microscope. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] Investigation of phase contrast hard X-ray microscopy using planar sets of refractive crossed linear parabolic lenses made from SU-8 polymerPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2007E. Reznikova Abstract Planar X-ray refractive lenses with parabolic surface profile, and in crossed geometry to provide 2D focusing, are fabricated from SU-8 polymer using the LIGA process and deep X-ray lithography technology. A transmission X-ray microscope (TXM) using a condenser and an objective lens based on this type of X-ray optics was set up at the ESRF beamline BM 5, for photon energies of 17.1 and 18 keV. Test structures made of gold and SU-8, with different thicknesses, were imaged with this TXM using in-line phase-contrast, with X-ray magnification factors of 13,20, spatial resolution between 0.2 and 0.3 µm and exposure times around 1 s. The advantages of a TXM based on refractive SU-8 planar crossed condenser and objective and the optimisation of the optical scheme and of the condenser focusing profile are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||